Merge remote-tracking branch 'origin/master'

[unleashed/lotheac.git] / usr / src / uts / common / io / gld.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 * Copyright (c) 2016 by Delphix. All rights reserved.
 */

/*
 * gld - Generic LAN Driver Version 2, PSARC/1997/382
 *
 * This is a utility module that provides generic facilities for
 * LAN  drivers.  The DLPI protocol and most STREAMS interfaces
 * are handled here.
 *
 * It no longer provides compatibility with drivers
 * implemented according to the GLD v0 documentation published
 * in 1993. (See PSARC 2003/728)
 */


#include <sys/types.h>
#include <sys/errno.h>
#include <sys/stropts.h>
#include <sys/stream.h>
#include <sys/kmem.h>
#include <sys/stat.h>
#include <sys/modctl.h>
#include <sys/kstat.h>
#include <sys/debug.h>
#include <sys/note.h>
#include <sys/sysmacros.h>

#include <sys/byteorder.h>
#include <sys/strsun.h>
#include <sys/strsubr.h>
#include <sys/dlpi.h>
#include <sys/pattr.h>
#include <sys/ethernet.h>
#include <sys/ib/clients/ibd/ibd.h>
#include <sys/policy.h>
#include <sys/atomic.h>

#include <sys/multidata.h>
#include <sys/gld.h>
#include <sys/gldpriv.h>

#include <sys/ddi.h>
#include <sys/sunddi.h>

/*
 * Macros to increment statistics.
 */

/*
 * Increase kstats. Note this operation is not atomic. It can be used when
 * GLDM_LOCK_HELD_WRITE(macinfo).
 */
#define BUMP(stats, vstats, stat, delta)        do {                    \
        ((stats)->stat) += (delta);                                     \
        _NOTE(CONSTANTCONDITION)                                        \
        if ((vstats) != NULL)                                           \
                ((struct gld_stats *)(vstats))->stat += (delta);        \
        _NOTE(CONSTANTCONDITION)                                        \
} while (0)

#define ATOMIC_BUMP_STAT(stat, delta)   do {                    \
        _NOTE(CONSTANTCONDITION)                                \
        if (sizeof ((stat)) == sizeof (uint32_t)) {             \
                atomic_add_32((uint32_t *)&(stat), (delta));    \
        _NOTE(CONSTANTCONDITION)                                \
        } else if (sizeof ((stat)) == sizeof (uint64_t)) {      \
                atomic_add_64((uint64_t *)&(stat), (delta));    \
        }                                                       \
        _NOTE(CONSTANTCONDITION)                                \
} while (0)

#define ATOMIC_BUMP(stats, vstats, stat, delta) do {                    \
        ATOMIC_BUMP_STAT((stats)->stat, (delta));                       \
        _NOTE(CONSTANTCONDITION)                                        \
        if ((vstats) != NULL) {                                         \
                ATOMIC_BUMP_STAT(((struct gld_stats *)(vstats))->stat,  \
                    (delta));                                           \
        }                                                               \
        _NOTE(CONSTANTCONDITION)                                        \
} while (0)

#define UPDATE_STATS(stats, vstats, pktinfo, delta) {                   \
        if ((pktinfo).isBroadcast) {                                    \
                ATOMIC_BUMP((stats), (vstats),                          \
                    glds_brdcstxmt, (delta));                           \
        } else if ((pktinfo).isMulticast) {                             \
                ATOMIC_BUMP((stats), (vstats), glds_multixmt, (delta)); \
        }                                                               \
        ATOMIC_BUMP((stats), (vstats), glds_bytexmt64,                  \
            ((pktinfo).pktLen));                                        \
        ATOMIC_BUMP((stats), (vstats), glds_pktxmt64, (delta));         \
}

#ifdef GLD_DEBUG
int gld_debug = GLDERRS;
#endif

/* called from gld_register */
static int gld_initstats(gld_mac_info_t *);

/* called from kstat mechanism, and from wsrv's get_statistics */
static int gld_update_kstat(kstat_t *, int);

/* statistics for additional vlans */
static int gld_init_vlan_stats(gld_vlan_t *);
static int gld_update_vlan_kstat(kstat_t *, int);

/* called from gld_getinfo */
static dev_info_t *gld_finddevinfo(dev_t);

/* called from wput, wsrv, unidata, and v0_sched to send a packet */
/* also from the source routing stuff for sending RDE protocol packets */
static int gld_start(queue_t *, mblk_t *, int, uint32_t);
static int gld_start_mdt(queue_t *, mblk_t *, int);

/* called from gld_start[_mdt] to loopback packet(s) in promiscuous mode */
static void gld_precv(gld_mac_info_t *, mblk_t *, uint32_t, struct gld_stats *);
static void gld_precv_mdt(gld_mac_info_t *, gld_vlan_t *, mblk_t *,
    pdesc_t *, pktinfo_t *);

/* receive group: called from gld_recv and gld_precv* with maclock held */
static void gld_sendup(gld_mac_info_t *, pktinfo_t *, mblk_t *,
    int (*)());
static int gld_accept(gld_t *, pktinfo_t *);
static int gld_mcmatch(gld_t *, pktinfo_t *);
static int gld_multicast(unsigned char *, gld_t *);
static int gld_paccept(gld_t *, pktinfo_t *);
static void gld_passon(gld_t *, mblk_t *, pktinfo_t *,
    void (*)(queue_t *, mblk_t *));
static mblk_t *gld_addudind(gld_t *, mblk_t *, pktinfo_t *, boolean_t);

/* wsrv group: called from wsrv, single threaded per queue */
static int gld_ioctl(queue_t *, mblk_t *);
static void gld_fastpath(gld_t *, queue_t *, mblk_t *);
static int gld_cmds(queue_t *, mblk_t *);
static mblk_t *gld_bindack(queue_t *, mblk_t *);
static int gld_notify_req(queue_t *, mblk_t *);
static int gld_udqos(queue_t *, mblk_t *);
static int gld_bind(queue_t *, mblk_t *);
static int gld_unbind(queue_t *, mblk_t *);
static int gld_inforeq(queue_t *, mblk_t *);
static int gld_unitdata(queue_t *, mblk_t *);
static int gldattach(queue_t *, mblk_t *);
static int gldunattach(queue_t *, mblk_t *);
static int gld_enable_multi(queue_t *, mblk_t *);
static int gld_disable_multi(queue_t *, mblk_t *);
static void gld_send_disable_multi(gld_mac_info_t *, gld_mcast_t *);
static int gld_promisc(queue_t *, mblk_t *, t_uscalar_t, boolean_t);
static int gld_physaddr(queue_t *, mblk_t *);
static int gld_setaddr(queue_t *, mblk_t *);
static int gld_get_statistics(queue_t *, mblk_t *);
static int gld_cap(queue_t *, mblk_t *);
static int gld_cap_ack(queue_t *, mblk_t *);
static int gld_cap_enable(queue_t *, mblk_t *);

/* misc utilities, some requiring various mutexes held */
static int gld_start_mac(gld_mac_info_t *);
static void gld_stop_mac(gld_mac_info_t *);
static void gld_set_ipq(gld_t *);
static void gld_flushqueue(queue_t *);
static glddev_t *gld_devlookup(int);
static int gld_findminor(glddev_t *);
static void gldinsque(void *, void *);
static void gldremque(void *);
void gld_bitrevcopy(caddr_t, caddr_t, size_t);
void gld_bitreverse(uchar_t *, size_t);
char *gld_macaddr_sprintf(char *, unsigned char *, int);
static gld_vlan_t *gld_add_vlan(gld_mac_info_t *, uint32_t vid);
static void gld_rem_vlan(gld_vlan_t *);
gld_vlan_t *gld_find_vlan(gld_mac_info_t *, uint32_t);
gld_vlan_t *gld_get_vlan(gld_mac_info_t *, uint32_t);

#ifdef GLD_DEBUG
static void gld_check_assertions(void);
extern void gld_sr_dump(gld_mac_info_t *);
#endif

/*
 * Allocate and zero-out "number" structures each of type "structure" in
 * kernel memory.
 */
#define GLD_GETSTRUCT(structure, number)   \
        (kmem_zalloc((uint_t)(sizeof (structure) * (number)), KM_NOSLEEP))

#define abs(a) ((a) < 0 ? -(a) : a)

uint32_t gld_global_options = GLD_OPT_NO_ETHRXSNAP;

/*
 * The device is of DL_ETHER type and is able to support VLAN by itself.
 */
#define VLAN_CAPABLE(macinfo) \
        ((macinfo)->gldm_type == DL_ETHER && \
        (macinfo)->gldm_send_tagged != NULL)

/*
 * The set of notifications generatable by GLD itself, the additional
 * set that can be generated if the MAC driver provide the link-state
 * tracking callback capability, and the set supported by the GLD
 * notification code below.
 *
 * PLEASE keep these in sync with what the code actually does!
 */
static const uint32_t gld_internal_notes =      DL_NOTE_PROMISC_ON_PHYS |
                                                DL_NOTE_PROMISC_OFF_PHYS |
                                                DL_NOTE_PHYS_ADDR;
static const uint32_t gld_linkstate_notes =     DL_NOTE_LINK_DOWN |
                                                DL_NOTE_LINK_UP |
                                                DL_NOTE_SPEED;
static const uint32_t gld_supported_notes =     DL_NOTE_PROMISC_ON_PHYS |
                                                DL_NOTE_PROMISC_OFF_PHYS |
                                                DL_NOTE_PHYS_ADDR |
                                                DL_NOTE_LINK_DOWN |
                                                DL_NOTE_LINK_UP |
                                                DL_NOTE_SPEED;

/* Media must correspond to #defines in gld.h */
static char *gld_media[] = {
        "unknown",      /* GLDM_UNKNOWN - driver cannot determine media */
        "aui",          /* GLDM_AUI */
        "bnc",          /* GLDM_BNC */
        "twpair",       /* GLDM_TP */
        "fiber",        /* GLDM_FIBER */
        "100baseT",     /* GLDM_100BT */
        "100vgAnyLan",  /* GLDM_VGANYLAN */
        "10baseT",      /* GLDM_10BT */
        "ring4",        /* GLDM_RING4 */
        "ring16",       /* GLDM_RING16 */
        "PHY/MII",      /* GLDM_PHYMII */
        "100baseTX",    /* GLDM_100BTX */
        "100baseT4",    /* GLDM_100BT4 */
        "unknown",      /* skip */
        "ipib",         /* GLDM_IB */
};

/* Must correspond to #defines in gld.h */
static char *gld_duplex[] = {
        "unknown",      /* GLD_DUPLEX_UNKNOWN - not known or not applicable */
        "half",         /* GLD_DUPLEX_HALF */
        "full"          /* GLD_DUPLEX_FULL */
};

/*
 * Interface types currently supported by GLD.
 * If you add new types, you must check all "XXX" strings in the GLD source
 * for implementation issues that may affect the support of your new type.
 * In particular, any type with gldm_addrlen > 6, or gldm_saplen != -2, will
 * require generalizing this GLD source to handle the new cases.  In other
 * words there are assumptions built into the code in a few places that must
 * be fixed.  Be sure to turn on DEBUG/ASSERT code when testing a new type.
 */
static gld_interface_t interfaces[] = {

        /* Ethernet Bus */
        {
                DL_ETHER,
                (uint_t)-1,
                sizeof (struct ether_header),
                gld_interpret_ether,
                NULL,
                gld_fastpath_ether,
                gld_unitdata_ether,
                gld_init_ether,
                gld_uninit_ether,
                "ether"
        },

        /* Fiber Distributed data interface */
        {
                DL_FDDI,
                4352,
                sizeof (struct fddi_mac_frm),
                gld_interpret_fddi,
                NULL,
                gld_fastpath_fddi,
                gld_unitdata_fddi,
                gld_init_fddi,
                gld_uninit_fddi,
                "fddi"
        },

        /* Token Ring interface */
        {
                DL_TPR,
                17914,
                -1,                     /* variable header size */
                gld_interpret_tr,
                NULL,
                gld_fastpath_tr,
                gld_unitdata_tr,
                gld_init_tr,
                gld_uninit_tr,
                "tpr"
        },

        /* Infiniband */
        {
                DL_IB,
                4092,
                sizeof (struct ipoib_header),
                gld_interpret_ib,
                gld_interpret_mdt_ib,
                gld_fastpath_ib,
                gld_unitdata_ib,
                gld_init_ib,
                gld_uninit_ib,
                "ipib"
        },
};

/*
 * bit reversal lookup table.
 */
static  uchar_t bit_rev[] = {
        0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0, 0x10, 0x90, 0x50, 0xd0,
        0x30, 0xb0, 0x70, 0xf0, 0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
        0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8, 0x04, 0x84, 0x44, 0xc4,
        0x24, 0xa4, 0x64, 0xe4, 0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
        0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec, 0x1c, 0x9c, 0x5c, 0xdc,
        0x3c, 0xbc, 0x7c, 0xfc, 0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
        0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2, 0x0a, 0x8a, 0x4a, 0xca,
        0x2a, 0xaa, 0x6a, 0xea, 0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
        0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6, 0x16, 0x96, 0x56, 0xd6,
        0x36, 0xb6, 0x76, 0xf6, 0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
        0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe, 0x01, 0x81, 0x41, 0xc1,
        0x21, 0xa1, 0x61, 0xe1, 0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
        0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9, 0x19, 0x99, 0x59, 0xd9,
        0x39, 0xb9, 0x79, 0xf9, 0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
        0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5, 0x0d, 0x8d, 0x4d, 0xcd,
        0x2d, 0xad, 0x6d, 0xed, 0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
        0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3, 0x13, 0x93, 0x53, 0xd3,
        0x33, 0xb3, 0x73, 0xf3, 0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
        0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb, 0x07, 0x87, 0x47, 0xc7,
        0x27, 0xa7, 0x67, 0xe7, 0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
        0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef, 0x1f, 0x9f, 0x5f, 0xdf,
        0x3f, 0xbf, 0x7f, 0xff,
};

/*
 * User priorities, mapped from b_band.
 */
static uint32_t user_priority[] = {
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
        1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
        2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
        2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
        3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
        3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
        4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
        4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
        5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
        5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
        6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
        6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6,
        7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7,
        7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7
};

#define UPRI(gld, band) ((band != 0) ? user_priority[(band)] : (gld)->gld_upri)

static struct glddevice gld_device_list;  /* Per-system root of GLD tables */

/*
 * Module linkage information for the kernel.
 */

static struct modldrv modlmisc = {
        &mod_miscops,           /* Type of module - a utility provider */
        "Generic LAN Driver (" GLD_VERSION_STRING ")"
#ifdef GLD_DEBUG
        " DEBUG"
#endif
};

static struct modlinkage modlinkage = {
        MODREV_1, &modlmisc, NULL
};

int
_init(void)
{
        int e;

        /* initialize gld_device_list mutex */
        mutex_init(&gld_device_list.gld_devlock, NULL, MUTEX_DRIVER, NULL);

        /* initialize device driver (per-major) list */
        gld_device_list.gld_next =
            gld_device_list.gld_prev = &gld_device_list;

        if ((e = mod_install(&modlinkage)) != 0)
                mutex_destroy(&gld_device_list.gld_devlock);

        return (e);
}

int
_fini(void)
{
        int e;

        if ((e = mod_remove(&modlinkage)) != 0)
                return (e);

        ASSERT(gld_device_list.gld_next ==
            (glddev_t *)&gld_device_list.gld_next);
        ASSERT(gld_device_list.gld_prev ==
            (glddev_t *)&gld_device_list.gld_next);
        mutex_destroy(&gld_device_list.gld_devlock);

        return (e);
}

int
_info(struct modinfo *modinfop)
{
        return (mod_info(&modlinkage, modinfop));
}

/*
 * GLD service routines
 */

/* So this gld binary maybe can be forward compatible with future v2 drivers */
#define GLD_MAC_RESERVED (16 * sizeof (caddr_t))

/*ARGSUSED*/
gld_mac_info_t *
gld_mac_alloc(dev_info_t *devinfo)
{
        gld_mac_info_t *macinfo;

        macinfo = kmem_zalloc(sizeof (gld_mac_info_t) + GLD_MAC_RESERVED,
            KM_SLEEP);

        /*
         * The setting of gldm_driver_version will not be documented or allowed
         * until a future release.
         */
        macinfo->gldm_driver_version = GLD_VERSION_200;

        /*
         * GLD's version.  This also is undocumented for now, but will be
         * available if needed in the future.
         */
        macinfo->gldm_GLD_version = GLD_VERSION;

        return (macinfo);
}

/*
 * gld_mac_free must be called after the driver has removed interrupts
 * and completely stopped calling gld_recv() and gld_sched().  At that
 * point the interrupt routine is guaranteed by the system to have been
 * exited and the maclock is no longer needed.  Of course, it is
 * expected (required) that (assuming gld_register() succeeded),
 * gld_unregister() was called before gld_mac_free().
 */
void
gld_mac_free(gld_mac_info_t *macinfo)
{
        ASSERT(macinfo);
        ASSERT(macinfo->gldm_GLD_version == GLD_VERSION);

        /*
         * Assert that if we made it through gld_register, then we must
         * have unregistered.
         */
        ASSERT(!GLDM_LOCK_INITED(macinfo) ||
            (macinfo->gldm_GLD_flags & GLD_UNREGISTERED));

        GLDM_LOCK_DESTROY(macinfo);

        kmem_free(macinfo, sizeof (gld_mac_info_t) + GLD_MAC_RESERVED);
}

/*
 * gld_register -- called once per device instance (PPA)
 *
 * During its attach routine, a real device driver will register with GLD
 * so that later opens and dl_attach_reqs will work.  The arguments are the
 * devinfo pointer, the device name, and a macinfo structure describing the
 * physical device instance.
 */
int
gld_register(dev_info_t *devinfo, char *devname, gld_mac_info_t *macinfo)
{
        int mediatype;
        int major = ddi_name_to_major(devname), i;
        glddev_t *glddev;
        gld_mac_pvt_t *mac_pvt;
        char minordev[32];
        char pbuf[3*GLD_MAX_ADDRLEN];
        gld_interface_t *ifp;

        ASSERT(devinfo != NULL);
        ASSERT(macinfo != NULL);

        if (macinfo->gldm_driver_version != GLD_VERSION)
                return (DDI_FAILURE);

        mediatype = macinfo->gldm_type;

        /*
         * Entry points should be ready for us.
         * ioctl is optional.
         * set_multicast and get_stats are optional in v0.
         * intr is only required if you add an interrupt.
         */
        ASSERT(macinfo->gldm_reset != NULL);
        ASSERT(macinfo->gldm_start != NULL);
        ASSERT(macinfo->gldm_stop != NULL);
        ASSERT(macinfo->gldm_set_mac_addr != NULL);
        ASSERT(macinfo->gldm_set_promiscuous != NULL);
        ASSERT(macinfo->gldm_send != NULL);

        ASSERT(macinfo->gldm_maxpkt >= macinfo->gldm_minpkt);
        ASSERT(macinfo->gldm_GLD_version == GLD_VERSION);
        ASSERT(macinfo->gldm_broadcast_addr != NULL);
        ASSERT(macinfo->gldm_vendor_addr != NULL);
        ASSERT(macinfo->gldm_ident != NULL);

        if (macinfo->gldm_addrlen > GLD_MAX_ADDRLEN) {
                cmn_err(CE_WARN, "GLD: %s driver gldm_addrlen %d > %d not sup"
                    "ported", devname, macinfo->gldm_addrlen, GLD_MAX_ADDRLEN);
                return (DDI_FAILURE);
        }

        /*
         * GLD only functions properly with saplen == -2
         */
        if (macinfo->gldm_saplen != -2) {
                cmn_err(CE_WARN, "GLD: %s driver gldm_saplen %d != -2 "
                    "not supported", devname, macinfo->gldm_saplen);
                return (DDI_FAILURE);
        }

        /* see gld_rsrv() */
        if (ddi_getprop(DDI_DEV_T_NONE, devinfo, 0, "fast_recv", 0))
                macinfo->gldm_options |= GLDOPT_FAST_RECV;

        mutex_enter(&gld_device_list.gld_devlock);
        glddev = gld_devlookup(major);

        /*
         *  Allocate per-driver (major) data structure if necessary
         */
        if (glddev == NULL) {
                /* first occurrence of this device name (major number) */
                glddev = GLD_GETSTRUCT(glddev_t, 1);
                if (glddev == NULL) {
                        mutex_exit(&gld_device_list.gld_devlock);
                        return (DDI_FAILURE);
                }
                (void) strncpy(glddev->gld_name, devname,
                    sizeof (glddev->gld_name) - 1);
                glddev->gld_major = major;
                glddev->gld_nextminor = GLD_MIN_CLONE_MINOR;
                glddev->gld_mac_next = glddev->gld_mac_prev =
                    (gld_mac_info_t *)&glddev->gld_mac_next;
                glddev->gld_str_next = glddev->gld_str_prev =
                    (gld_t *)&glddev->gld_str_next;
                mutex_init(&glddev->gld_devlock, NULL, MUTEX_DRIVER, NULL);

                /* allow increase of number of supported multicast addrs */
                glddev->gld_multisize = ddi_getprop(DDI_DEV_T_NONE,
                    devinfo, 0, "multisize", GLD_MAX_MULTICAST);

                /*
                 * Optionally restrict DLPI provider style
                 *
                 * -1 - don't create style 1 nodes
                 * -2 - don't create style 2 nodes
                 */
                glddev->gld_styles = ddi_getprop(DDI_DEV_T_NONE, devinfo, 0,
                    "gld-provider-styles", 0);

                /* Stuff that's needed before any PPA gets attached */
                glddev->gld_type = macinfo->gldm_type;
                glddev->gld_minsdu = macinfo->gldm_minpkt;
                glddev->gld_saplen = macinfo->gldm_saplen;
                glddev->gld_addrlen = macinfo->gldm_addrlen;
                glddev->gld_broadcast = kmem_zalloc(macinfo->gldm_addrlen,
                    KM_SLEEP);
                bcopy(macinfo->gldm_broadcast_addr,
                    glddev->gld_broadcast, macinfo->gldm_addrlen);
                glddev->gld_maxsdu = macinfo->gldm_maxpkt;
                gldinsque(glddev, gld_device_list.gld_prev);
        }
        glddev->gld_ndevice++;
        /* Now glddev can't go away until we unregister this mac (or fail) */
        mutex_exit(&gld_device_list.gld_devlock);

        /*
         *  Per-instance initialization
         */

        /*
         * Initialize per-mac structure that is private to GLD.
         * Set up interface pointer. These are device class specific pointers
         * used to handle FDDI/TR/ETHER/IPoIB specific packets.
         */
        for (i = 0; i < sizeof (interfaces)/sizeof (*interfaces); i++) {
                if (mediatype != interfaces[i].mac_type)
                        continue;

                macinfo->gldm_mac_pvt = kmem_zalloc(sizeof (gld_mac_pvt_t),
                    KM_SLEEP);
                ((gld_mac_pvt_t *)macinfo->gldm_mac_pvt)->interfacep = ifp =
                    &interfaces[i];
                break;
        }

        if (ifp == NULL) {
                cmn_err(CE_WARN, "GLD: this version does not support %s driver "
                    "of type %d", devname, mediatype);
                goto failure;
        }

        /*
         * Driver can only register MTU within legal media range.
         */
        if (macinfo->gldm_maxpkt > ifp->mtu_size) {
                cmn_err(CE_WARN, "GLD: oversize MTU is specified by driver %s",
                    devname);
                goto failure;
        }

        /*
         * Correct margin size if it is not set.
         */
        if (VLAN_CAPABLE(macinfo) && (macinfo->gldm_margin == 0))
                macinfo->gldm_margin = VTAG_SIZE;

        /*
         * For now, only Infiniband drivers can use MDT. Do not add
         * support for Ethernet, FDDI or TR.
         */
        if (macinfo->gldm_mdt_pre != NULL) {
                if (mediatype != DL_IB) {
                        cmn_err(CE_WARN, "GLD: MDT not supported for %s "
                            "driver of type %d", devname, mediatype);
                        goto failure;
                }

                /*
                 * Validate entry points.
                 */
                if ((macinfo->gldm_mdt_send == NULL) ||
                    (macinfo->gldm_mdt_post == NULL)) {
                        cmn_err(CE_WARN, "GLD: invalid MDT entry points for "
                            "%s driver of type %d", devname, mediatype);
                        goto failure;
                }
                macinfo->gldm_options |= GLDOPT_MDT;
        }

        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        mac_pvt->major_dev = glddev;

        mac_pvt->curr_macaddr = kmem_zalloc(macinfo->gldm_addrlen, KM_SLEEP);
        /*
         * XXX Do bit-reversed devices store gldm_vendor in canonical
         * format or in wire format?  Also gldm_broadcast.  For now
         * we are assuming canonical, but I'm not sure that makes the
         * most sense for ease of driver implementation.
         */
        bcopy(macinfo->gldm_vendor_addr, mac_pvt->curr_macaddr,
            macinfo->gldm_addrlen);
        mac_pvt->statistics = kmem_zalloc(sizeof (struct gld_stats), KM_SLEEP);

        /*
         * The available set of notifications is those generatable by GLD
         * itself, plus those corresponding to the capabilities of the MAC
         * driver, intersected with those supported by gld_notify_ind() above.
         */
        mac_pvt->notifications = gld_internal_notes;
        if (macinfo->gldm_capabilities & GLD_CAP_LINKSTATE)
                mac_pvt->notifications |= gld_linkstate_notes;
        mac_pvt->notifications &= gld_supported_notes;

        GLDM_LOCK_INIT(macinfo);

        ddi_set_driver_private(devinfo, macinfo);

        /*
         * Now atomically get a PPA and put ourselves on the mac list.
         */
        mutex_enter(&glddev->gld_devlock);

#ifdef DEBUG
        if (macinfo->gldm_ppa != ddi_get_instance(devinfo))
                cmn_err(CE_WARN, "%s%d instance != ppa %d",
                    ddi_driver_name(devinfo), ddi_get_instance(devinfo),
                    macinfo->gldm_ppa);
#endif

        /*
         * Create style 2 node (gated by gld-provider-styles property).
         *
         * NOTE: When the CLONE_DEV flag is specified to
         *       ddi_create_minor_node() the minor number argument is
         *       immaterial. Opens of that node will go via the clone
         *       driver and gld_open() will always be passed a dev_t with
         *       minor of zero.
         */
        if (glddev->gld_styles != -2) {
                if (ddi_create_minor_node(devinfo, glddev->gld_name, S_IFCHR,
                    0, DDI_NT_NET, CLONE_DEV) == DDI_FAILURE) {
                        mutex_exit(&glddev->gld_devlock);
                        goto late_failure;
                }
        }

        /*
         * Create style 1 node (gated by gld-provider-styles property)
         */
        if (glddev->gld_styles != -1) {
                (void) sprintf(minordev, "%s%d", glddev->gld_name,
                    macinfo->gldm_ppa);
                if (ddi_create_minor_node(devinfo, minordev, S_IFCHR,
                    GLD_STYLE1_PPA_TO_MINOR(macinfo->gldm_ppa), DDI_NT_NET,
                    0) != DDI_SUCCESS) {
                        mutex_exit(&glddev->gld_devlock);
                        goto late_failure;
                }
        }

        /* add ourselves to this major device's linked list of instances */
        gldinsque(macinfo, glddev->gld_mac_prev);

        mutex_exit(&glddev->gld_devlock);

        /*
         * Unfortunately we need the ppa before we call gld_initstats();
         * otherwise we would like to do this just above the mutex_enter
         * above.  In which case we could have set MAC_READY inside the
         * mutex and we wouldn't have needed to check it in open and
         * DL_ATTACH.  We wouldn't like to do the initstats/kstat_create
         * inside the mutex because it might get taken in our kstat_update
         * routine and cause a deadlock with kstat_chain_lock.
         */

        /* gld_initstats() calls (*ifp->init)() */
        if (gld_initstats(macinfo) != GLD_SUCCESS) {
                mutex_enter(&glddev->gld_devlock);
                gldremque(macinfo);
                mutex_exit(&glddev->gld_devlock);
                goto late_failure;
        }

        /*
         * Need to indicate we are NOW ready to process interrupts;
         * any interrupt before this is set is for someone else.
         * This flag is also now used to tell open, et. al. that this
         * mac is now fully ready and available for use.
         */
        GLDM_LOCK(macinfo, RW_WRITER);
        macinfo->gldm_GLD_flags |= GLD_MAC_READY;
        GLDM_UNLOCK(macinfo);

        /* log local ethernet address -- XXX not DDI compliant */
        if (macinfo->gldm_addrlen == sizeof (struct ether_addr))
                (void) localetheraddr(
                    (struct ether_addr *)macinfo->gldm_vendor_addr, NULL);

        /* now put announcement into the message buffer */
        cmn_err(CE_CONT, "!%s%d: %s: type \"%s\" mac address %s\n",
            glddev->gld_name,
            macinfo->gldm_ppa, macinfo->gldm_ident,
            mac_pvt->interfacep->mac_string,
            gld_macaddr_sprintf(pbuf, macinfo->gldm_vendor_addr,
            macinfo->gldm_addrlen));

        ddi_report_dev(devinfo);
        return (DDI_SUCCESS);

late_failure:
        ddi_remove_minor_node(devinfo, NULL);
        GLDM_LOCK_DESTROY(macinfo);
        if (mac_pvt->curr_macaddr != NULL)
                kmem_free(mac_pvt->curr_macaddr, macinfo->gldm_addrlen);
        if (mac_pvt->statistics != NULL)
                kmem_free(mac_pvt->statistics, sizeof (struct gld_stats));
        kmem_free(macinfo->gldm_mac_pvt, sizeof (gld_mac_pvt_t));
        macinfo->gldm_mac_pvt = NULL;

failure:
        mutex_enter(&gld_device_list.gld_devlock);
        glddev->gld_ndevice--;
        /*
         * Note that just because this goes to zero here does not necessarily
         * mean that we were the one who added the glddev above.  It's
         * possible that the first mac unattached while were were in here
         * failing to attach the second mac.  But we're now the last.
         */
        if (glddev->gld_ndevice == 0) {
                /* There should be no macinfos left */
                ASSERT(glddev->gld_mac_next ==
                    (gld_mac_info_t *)&glddev->gld_mac_next);
                ASSERT(glddev->gld_mac_prev ==
                    (gld_mac_info_t *)&glddev->gld_mac_next);

                /*
                 * There should be no DL_UNATTACHED streams: the system
                 * should not have detached the "first" devinfo which has
                 * all the open style 2 streams.
                 *
                 * XXX This is not clear.  See gld_getinfo and Bug 1165519
                 */
                ASSERT(glddev->gld_str_next == (gld_t *)&glddev->gld_str_next);
                ASSERT(glddev->gld_str_prev == (gld_t *)&glddev->gld_str_next);

                gldremque(glddev);
                mutex_destroy(&glddev->gld_devlock);
                if (glddev->gld_broadcast != NULL)
                        kmem_free(glddev->gld_broadcast, glddev->gld_addrlen);
                kmem_free(glddev, sizeof (glddev_t));
        }
        mutex_exit(&gld_device_list.gld_devlock);

        return (DDI_FAILURE);
}

/*
 * gld_unregister (macinfo)
 * remove the macinfo structure from local structures
 * this is cleanup for a driver to be unloaded
 */
int
gld_unregister(gld_mac_info_t *macinfo)
{
        gld_mac_pvt_t *mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        glddev_t *glddev = mac_pvt->major_dev;
        gld_interface_t *ifp;
        int multisize = sizeof (gld_mcast_t) * glddev->gld_multisize;

        mutex_enter(&glddev->gld_devlock);
        GLDM_LOCK(macinfo, RW_WRITER);

        if (mac_pvt->nvlan > 0) {
                GLDM_UNLOCK(macinfo);
                mutex_exit(&glddev->gld_devlock);
                return (DDI_FAILURE);
        }

#ifdef  GLD_DEBUG
        {
                int i;

                for (i = 0; i < VLAN_HASHSZ; i++) {
                        if ((mac_pvt->vlan_hash[i] != NULL))
                                cmn_err(CE_PANIC,
                                    "%s, line %d: "
                                    "mac_pvt->vlan_hash[%d] != NULL",
                                    __FILE__, __LINE__, i);
                }
        }
#endif

        /* Delete this mac */
        gldremque(macinfo);

        /* Disallow further entries to gld_recv() and gld_sched() */
        macinfo->gldm_GLD_flags |= GLD_UNREGISTERED;

        GLDM_UNLOCK(macinfo);
        mutex_exit(&glddev->gld_devlock);

        ifp = ((gld_mac_pvt_t *)macinfo->gldm_mac_pvt)->interfacep;
        (*ifp->uninit)(macinfo);

        ASSERT(mac_pvt->kstatp);
        kstat_delete(mac_pvt->kstatp);

        ASSERT(GLDM_LOCK_INITED(macinfo));
        kmem_free(mac_pvt->curr_macaddr, macinfo->gldm_addrlen);
        kmem_free(mac_pvt->statistics, sizeof (struct gld_stats));

        if (mac_pvt->mcast_table != NULL)
                kmem_free(mac_pvt->mcast_table, multisize);
        kmem_free(macinfo->gldm_mac_pvt, sizeof (gld_mac_pvt_t));
        macinfo->gldm_mac_pvt = NULL;

        /* We now have one fewer instance for this major device */
        mutex_enter(&gld_device_list.gld_devlock);
        glddev->gld_ndevice--;
        if (glddev->gld_ndevice == 0) {
                /* There should be no macinfos left */
                ASSERT(glddev->gld_mac_next ==
                    (gld_mac_info_t *)&glddev->gld_mac_next);
                ASSERT(glddev->gld_mac_prev ==
                    (gld_mac_info_t *)&glddev->gld_mac_next);

                /*
                 * There should be no DL_UNATTACHED streams: the system
                 * should not have detached the "first" devinfo which has
                 * all the open style 2 streams.
                 *
                 * XXX This is not clear.  See gld_getinfo and Bug 1165519
                 */
                ASSERT(glddev->gld_str_next == (gld_t *)&glddev->gld_str_next);
                ASSERT(glddev->gld_str_prev == (gld_t *)&glddev->gld_str_next);

                ddi_remove_minor_node(macinfo->gldm_devinfo, NULL);
                gldremque(glddev);
                mutex_destroy(&glddev->gld_devlock);
                if (glddev->gld_broadcast != NULL)
                        kmem_free(glddev->gld_broadcast, glddev->gld_addrlen);
                kmem_free(glddev, sizeof (glddev_t));
        }
        mutex_exit(&gld_device_list.gld_devlock);

        return (DDI_SUCCESS);
}

/*
 * gld_initstats
 * called from gld_register
 */
static int
gld_initstats(gld_mac_info_t *macinfo)
{
        gld_mac_pvt_t *mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        struct gldkstats *sp;
        glddev_t *glddev;
        kstat_t *ksp;
        gld_interface_t *ifp;

        glddev = mac_pvt->major_dev;

        if ((ksp = kstat_create(glddev->gld_name, macinfo->gldm_ppa,
            NULL, "net", KSTAT_TYPE_NAMED,
            sizeof (struct gldkstats) / sizeof (kstat_named_t), 0)) == NULL) {
                cmn_err(CE_WARN,
                    "GLD: failed to create kstat structure for %s%d",
                    glddev->gld_name, macinfo->gldm_ppa);
                return (GLD_FAILURE);
        }
        mac_pvt->kstatp = ksp;

        ksp->ks_update = gld_update_kstat;
        ksp->ks_private = (void *)macinfo;

        sp = ksp->ks_data;
        kstat_named_init(&sp->glds_pktrcv, "ipackets", KSTAT_DATA_UINT32);
        kstat_named_init(&sp->glds_pktxmt, "opackets", KSTAT_DATA_UINT32);
        kstat_named_init(&sp->glds_errrcv, "ierrors", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_errxmt, "oerrors", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_bytexmt, "obytes", KSTAT_DATA_UINT32);
        kstat_named_init(&sp->glds_bytercv, "rbytes", KSTAT_DATA_UINT32);
        kstat_named_init(&sp->glds_multixmt, "multixmt", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_multircv, "multircv", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_brdcstxmt, "brdcstxmt", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_brdcstrcv, "brdcstrcv", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_blocked, "blocked", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_noxmtbuf, "noxmtbuf", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_norcvbuf, "norcvbuf", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_xmtretry, "xmtretry", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_intr, "intr", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_pktrcv64, "ipackets64", KSTAT_DATA_UINT64);
        kstat_named_init(&sp->glds_pktxmt64, "opackets64", KSTAT_DATA_UINT64);
        kstat_named_init(&sp->glds_bytexmt64, "obytes64", KSTAT_DATA_UINT64);
        kstat_named_init(&sp->glds_bytercv64, "rbytes64", KSTAT_DATA_UINT64);
        kstat_named_init(&sp->glds_unknowns, "unknowns", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_speed, "ifspeed", KSTAT_DATA_UINT64);
        kstat_named_init(&sp->glds_media, "media", KSTAT_DATA_CHAR);
        kstat_named_init(&sp->glds_prom, "promisc", KSTAT_DATA_CHAR);

        kstat_named_init(&sp->glds_overflow, "oflo", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_underflow, "uflo", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_missed, "missed", KSTAT_DATA_ULONG);

        kstat_named_init(&sp->glds_xmtbadinterp, "xmt_badinterp",
            KSTAT_DATA_UINT32);
        kstat_named_init(&sp->glds_rcvbadinterp, "rcv_badinterp",
            KSTAT_DATA_UINT32);

        ifp = ((gld_mac_pvt_t *)macinfo->gldm_mac_pvt)->interfacep;

        (*ifp->init)(macinfo);

        kstat_install(ksp);

        return (GLD_SUCCESS);
}

/* called from kstat mechanism, and from wsrv's get_statistics_req */
static int
gld_update_kstat(kstat_t *ksp, int rw)
{
        gld_mac_info_t  *macinfo;
        gld_mac_pvt_t   *mac_pvt;
        struct gldkstats *gsp;
        struct gld_stats *stats;

        if (rw == KSTAT_WRITE)
                return (EACCES);

        macinfo = (gld_mac_info_t *)ksp->ks_private;
        ASSERT(macinfo != NULL);

        GLDM_LOCK(macinfo, RW_WRITER);

        if (!(macinfo->gldm_GLD_flags & GLD_MAC_READY)) {
                GLDM_UNLOCK(macinfo);
                return (EIO);   /* this one's not ready yet */
        }

        if (macinfo->gldm_GLD_flags & GLD_UNREGISTERED) {
                GLDM_UNLOCK(macinfo);
                return (EIO);   /* this one's not ready any more */
        }

        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        gsp = mac_pvt->kstatp->ks_data;
        ASSERT(gsp);
        stats = mac_pvt->statistics;

        if (macinfo->gldm_get_stats)
                (void) (*macinfo->gldm_get_stats)(macinfo, stats);

        gsp->glds_pktxmt.value.ui32 = stats->glds_pktxmt64 & 0xffffffff;
        gsp->glds_bytexmt.value.ui32 = stats->glds_bytexmt64 & 0xffffffff;
        gsp->glds_multixmt.value.ul = stats->glds_multixmt;
        gsp->glds_brdcstxmt.value.ul = stats->glds_brdcstxmt;
        gsp->glds_noxmtbuf.value.ul = stats->glds_noxmtbuf;     /* 0 for now */
        gsp->glds_xmtretry.value.ul = stats->glds_xmtretry;

        gsp->glds_pktxmt64.value.ui64 = stats->glds_pktxmt64;
        gsp->glds_bytexmt64.value.ui64 = stats->glds_bytexmt64;
        gsp->glds_xmtbadinterp.value.ui32 = stats->glds_xmtbadinterp;

        gsp->glds_pktrcv.value.ui32 = stats->glds_pktrcv64 & 0xffffffff;
        gsp->glds_errxmt.value.ul = stats->glds_errxmt;
        gsp->glds_errrcv.value.ul = stats->glds_errrcv;
        gsp->glds_bytercv.value.ui32 = stats->glds_bytercv64 & 0xffffffff;
        gsp->glds_multircv.value.ul = stats->glds_multircv;
        gsp->glds_brdcstrcv.value.ul = stats->glds_brdcstrcv;
        gsp->glds_blocked.value.ul = stats->glds_blocked;
        gsp->glds_overflow.value.ul = stats->glds_overflow;
        gsp->glds_underflow.value.ul = stats->glds_underflow;
        gsp->glds_missed.value.ul = stats->glds_missed;
        gsp->glds_norcvbuf.value.ul = stats->glds_norcvbuf +
            stats->glds_gldnorcvbuf;
        gsp->glds_intr.value.ul = stats->glds_intr;

        gsp->glds_speed.value.ui64 = stats->glds_speed;
        gsp->glds_unknowns.value.ul = stats->glds_unknowns;
        gsp->glds_pktrcv64.value.ui64 = stats->glds_pktrcv64;
        gsp->glds_bytercv64.value.ui64 = stats->glds_bytercv64;
        gsp->glds_rcvbadinterp.value.ui32 = stats->glds_rcvbadinterp;

        if (mac_pvt->nprom)
                (void) strcpy(gsp->glds_prom.value.c, "phys");
        else if (mac_pvt->nprom_multi)
                (void) strcpy(gsp->glds_prom.value.c, "multi");
        else
                (void) strcpy(gsp->glds_prom.value.c, "off");

        (void) strcpy(gsp->glds_media.value.c, gld_media[
            stats->glds_media < sizeof (gld_media) / sizeof (gld_media[0])
            ? stats->glds_media : 0]);

        switch (macinfo->gldm_type) {
        case DL_ETHER:
                gsp->glds_frame.value.ul = stats->glds_frame;
                gsp->glds_crc.value.ul = stats->glds_crc;
                gsp->glds_collisions.value.ul = stats->glds_collisions;
                gsp->glds_excoll.value.ul = stats->glds_excoll;
                gsp->glds_defer.value.ul = stats->glds_defer;
                gsp->glds_short.value.ul = stats->glds_short;
                gsp->glds_xmtlatecoll.value.ul = stats->glds_xmtlatecoll;
                gsp->glds_nocarrier.value.ul = stats->glds_nocarrier;
                gsp->glds_dot3_first_coll.value.ui32 =
                    stats->glds_dot3_first_coll;
                gsp->glds_dot3_multi_coll.value.ui32 =
                    stats->glds_dot3_multi_coll;
                gsp->glds_dot3_sqe_error.value.ui32 =
                    stats->glds_dot3_sqe_error;
                gsp->glds_dot3_mac_xmt_error.value.ui32 =
                    stats->glds_dot3_mac_xmt_error;
                gsp->glds_dot3_mac_rcv_error.value.ui32 =
                    stats->glds_dot3_mac_rcv_error;
                gsp->glds_dot3_frame_too_long.value.ui32 =
                    stats->glds_dot3_frame_too_long;
                (void) strcpy(gsp->glds_duplex.value.c, gld_duplex[
                    stats->glds_duplex <
                    sizeof (gld_duplex) / sizeof (gld_duplex[0]) ?
                    stats->glds_duplex : 0]);
                break;
        case DL_TPR:
                gsp->glds_dot5_line_error.value.ui32 =
                    stats->glds_dot5_line_error;
                gsp->glds_dot5_burst_error.value.ui32 =
                    stats->glds_dot5_burst_error;
                gsp->glds_dot5_signal_loss.value.ui32 =
                    stats->glds_dot5_signal_loss;
                gsp->glds_dot5_ace_error.value.ui32 =
                    stats->glds_dot5_ace_error;
                gsp->glds_dot5_internal_error.value.ui32 =
                    stats->glds_dot5_internal_error;
                gsp->glds_dot5_lost_frame_error.value.ui32 =
                    stats->glds_dot5_lost_frame_error;
                gsp->glds_dot5_frame_copied_error.value.ui32 =
                    stats->glds_dot5_frame_copied_error;
                gsp->glds_dot5_token_error.value.ui32 =
                    stats->glds_dot5_token_error;
                gsp->glds_dot5_freq_error.value.ui32 =
                    stats->glds_dot5_freq_error;
                break;
        case DL_FDDI:
                gsp->glds_fddi_mac_error.value.ui32 =
                    stats->glds_fddi_mac_error;
                gsp->glds_fddi_mac_lost.value.ui32 =
                    stats->glds_fddi_mac_lost;
                gsp->glds_fddi_mac_token.value.ui32 =
                    stats->glds_fddi_mac_token;
                gsp->glds_fddi_mac_tvx_expired.value.ui32 =
                    stats->glds_fddi_mac_tvx_expired;
                gsp->glds_fddi_mac_late.value.ui32 =
                    stats->glds_fddi_mac_late;
                gsp->glds_fddi_mac_ring_op.value.ui32 =
                    stats->glds_fddi_mac_ring_op;
                break;
        case DL_IB:
                break;
        default:
                break;
        }

        GLDM_UNLOCK(macinfo);

#ifdef GLD_DEBUG
        gld_check_assertions();
        if (gld_debug & GLDRDE)
                gld_sr_dump(macinfo);
#endif

        return (0);
}

static int
gld_init_vlan_stats(gld_vlan_t *vlan)
{
        gld_mac_info_t *mac = vlan->gldv_mac;
        gld_mac_pvt_t *mac_pvt = (gld_mac_pvt_t *)mac->gldm_mac_pvt;
        struct gldkstats *sp;
        glddev_t *glddev;
        kstat_t *ksp;
        char *name;
        int instance;

        glddev = mac_pvt->major_dev;
        name = glddev->gld_name;
        instance = (vlan->gldv_id * GLD_VLAN_SCALE) + mac->gldm_ppa;

        if ((ksp = kstat_create(name, instance,
            NULL, "net", KSTAT_TYPE_NAMED,
            sizeof (struct gldkstats) / sizeof (kstat_named_t), 0)) == NULL) {
                cmn_err(CE_WARN,
                    "GLD: failed to create kstat structure for %s%d",
                    name, instance);
                return (GLD_FAILURE);
        }

        vlan->gldv_kstatp = ksp;

        ksp->ks_update = gld_update_vlan_kstat;
        ksp->ks_private = (void *)vlan;

        sp = ksp->ks_data;
        kstat_named_init(&sp->glds_pktrcv, "ipackets", KSTAT_DATA_UINT32);
        kstat_named_init(&sp->glds_pktxmt, "opackets", KSTAT_DATA_UINT32);
        kstat_named_init(&sp->glds_errrcv, "ierrors", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_errxmt, "oerrors", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_bytexmt, "obytes", KSTAT_DATA_UINT32);
        kstat_named_init(&sp->glds_bytercv, "rbytes", KSTAT_DATA_UINT32);
        kstat_named_init(&sp->glds_multixmt, "multixmt", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_multircv, "multircv", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_brdcstxmt, "brdcstxmt", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_brdcstrcv, "brdcstrcv", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_blocked, "blocked", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_noxmtbuf, "noxmtbuf", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_norcvbuf, "norcvbuf", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_xmtretry, "xmtretry", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_intr, "intr", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_pktrcv64, "ipackets64", KSTAT_DATA_UINT64);
        kstat_named_init(&sp->glds_pktxmt64, "opackets64", KSTAT_DATA_UINT64);
        kstat_named_init(&sp->glds_bytexmt64, "obytes64", KSTAT_DATA_UINT64);
        kstat_named_init(&sp->glds_bytercv64, "rbytes64", KSTAT_DATA_UINT64);
        kstat_named_init(&sp->glds_unknowns, "unknowns", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_speed, "ifspeed", KSTAT_DATA_UINT64);
        kstat_named_init(&sp->glds_media, "media", KSTAT_DATA_CHAR);
        kstat_named_init(&sp->glds_prom, "promisc", KSTAT_DATA_CHAR);

        kstat_named_init(&sp->glds_overflow, "oflo", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_underflow, "uflo", KSTAT_DATA_ULONG);
        kstat_named_init(&sp->glds_missed, "missed", KSTAT_DATA_ULONG);

        kstat_named_init(&sp->glds_xmtbadinterp, "xmt_badinterp",
            KSTAT_DATA_UINT32);
        kstat_named_init(&sp->glds_rcvbadinterp, "rcv_badinterp",
            KSTAT_DATA_UINT32);

        kstat_install(ksp);
        return (GLD_SUCCESS);
}

static int
gld_update_vlan_kstat(kstat_t *ksp, int rw)
{
        gld_vlan_t      *vlan;
        gld_mac_info_t  *macinfo;
        struct gldkstats *gsp;
        struct gld_stats *stats;
        gld_mac_pvt_t *mac_pvt;
        uint32_t media;

        if (rw == KSTAT_WRITE)
                return (EACCES);

        vlan = (gld_vlan_t *)ksp->ks_private;
        ASSERT(vlan != NULL);

        macinfo = vlan->gldv_mac;
        GLDM_LOCK(macinfo, RW_WRITER);

        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;

        gsp = vlan->gldv_kstatp->ks_data;
        ASSERT(gsp);
        stats = vlan->gldv_stats;

        gsp->glds_pktxmt.value.ui32 = stats->glds_pktxmt64 & 0xffffffff;
        gsp->glds_bytexmt.value.ui32 = stats->glds_bytexmt64 & 0xffffffff;
        gsp->glds_errxmt.value.ul = stats->glds_errxmt;
        gsp->glds_multixmt.value.ul = stats->glds_multixmt;
        gsp->glds_brdcstxmt.value.ul = stats->glds_brdcstxmt;
        gsp->glds_noxmtbuf.value.ul = stats->glds_noxmtbuf;
        gsp->glds_xmtretry.value.ul = stats->glds_xmtretry;
        gsp->glds_pktxmt64.value.ui64 = stats->glds_pktxmt64;
        gsp->glds_bytexmt64.value.ui64 = stats->glds_bytexmt64;

        gsp->glds_pktrcv.value.ui32 = stats->glds_pktrcv64 & 0xffffffff;
        gsp->glds_bytercv.value.ui32 = stats->glds_bytercv64 & 0xffffffff;
        gsp->glds_errrcv.value.ul = stats->glds_errrcv;
        gsp->glds_multircv.value.ul = stats->glds_multircv;
        gsp->glds_brdcstrcv.value.ul = stats->glds_brdcstrcv;
        gsp->glds_blocked.value.ul = stats->glds_blocked;
        gsp->glds_pktrcv64.value.ui64 = stats->glds_pktrcv64;
        gsp->glds_bytercv64.value.ui64 = stats->glds_bytercv64;
        gsp->glds_unknowns.value.ul = stats->glds_unknowns;
        gsp->glds_xmtbadinterp.value.ui32 = stats->glds_xmtbadinterp;
        gsp->glds_rcvbadinterp.value.ui32 = stats->glds_rcvbadinterp;

        gsp->glds_speed.value.ui64 = mac_pvt->statistics->glds_speed;
        media = mac_pvt->statistics->glds_media;
        (void) strcpy(gsp->glds_media.value.c,
            gld_media[media < sizeof (gld_media) / sizeof (gld_media[0]) ?
            media : 0]);

        GLDM_UNLOCK(macinfo);
        return (0);
}

/*
 * The device dependent driver specifies gld_getinfo as its getinfo routine.
 */
/*ARGSUSED*/
int
gld_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd, void *arg, void **resultp)
{
        dev_info_t      *devinfo;
        minor_t         minor = getminor((dev_t)arg);
        int             rc = DDI_FAILURE;

        switch (cmd) {
        case DDI_INFO_DEVT2DEVINFO:
                if ((devinfo = gld_finddevinfo((dev_t)arg)) != NULL) {
                        *(dev_info_t **)resultp = devinfo;
                        rc = DDI_SUCCESS;
                }
                break;
        case DDI_INFO_DEVT2INSTANCE:
                /* Need static mapping for deferred attach */
                if (minor == GLD_USE_STYLE2) {
                        /*
                         * Style 2:  this minor number does not correspond to
                         * any particular instance number.
                         */
                        rc = DDI_FAILURE;
                } else if (minor <= GLD_MAX_STYLE1_MINOR) {
                        /* Style 1:  calculate the PPA from the minor */
                        *resultp = (void *)(uintptr_t)
                            GLD_STYLE1_MINOR_TO_PPA(minor);
                        rc = DDI_SUCCESS;
                } else {
                        /* Clone:  look for it.  Not a static mapping */
                        if ((devinfo = gld_finddevinfo((dev_t)arg)) != NULL) {
                                *resultp = (void *)(uintptr_t)
                                    ddi_get_instance(devinfo);
                                rc = DDI_SUCCESS;
                        }
                }
                break;
        }

        return (rc);
}

/* called from gld_getinfo */
dev_info_t *
gld_finddevinfo(dev_t dev)
{
        minor_t         minor = getminor(dev);
        glddev_t        *device;
        gld_mac_info_t  *mac;
        gld_vlan_t      *vlan;
        gld_t           *str;
        dev_info_t      *devinfo = NULL;
        int             i;

        if (minor == GLD_USE_STYLE2) {
                /*
                 * Style 2:  this minor number does not correspond to
                 * any particular instance number.
                 *
                 * XXX We don't know what to say.  See Bug 1165519.
                 */
                return (NULL);
        }

        mutex_enter(&gld_device_list.gld_devlock);      /* hold the device */

        device = gld_devlookup(getmajor(dev));
        if (device == NULL) {
                /* There are no attached instances of this device */
                mutex_exit(&gld_device_list.gld_devlock);
                return (NULL);
        }

        /*
         * Search all attached macs and streams.
         *
         * XXX We don't bother checking the DL_UNATTACHED streams since
         * we don't know what devinfo we should report back even if we
         * found the minor.  Maybe we should associate streams that are
         * not currently attached to a PPA with the "first" devinfo node
         * of the major device to attach -- the one that created the
         * minor node for the generic device.
         */
        mutex_enter(&device->gld_devlock);

        for (mac = device->gld_mac_next;
            mac != (gld_mac_info_t *)&device->gld_mac_next;
            mac = mac->gldm_next) {
                gld_mac_pvt_t *pvt = (gld_mac_pvt_t *)mac->gldm_mac_pvt;

                if (!(mac->gldm_GLD_flags & GLD_MAC_READY))
                        continue;       /* this one's not ready yet */
                if (minor <= GLD_MAX_STYLE1_MINOR) {
                        /* Style 1 -- look for the corresponding PPA */
                        if (minor == GLD_STYLE1_PPA_TO_MINOR(mac->gldm_ppa)) {
                                devinfo = mac->gldm_devinfo;
                                goto out;       /* found it! */
                        } else
                                continue;       /* not this PPA */
                }

                /* We are looking for a clone */
                for (i = 0; i < VLAN_HASHSZ; i++) {
                        for (vlan = pvt->vlan_hash[i];
                            vlan != NULL; vlan = vlan->gldv_next) {
                                for (str = vlan->gldv_str_next;
                                    str != (gld_t *)&vlan->gldv_str_next;
                                    str = str->gld_next) {
                                        ASSERT(str->gld_mac_info == mac);
                                        if (minor == str->gld_minor) {
                                                devinfo = mac->gldm_devinfo;
                                                goto out;
                                        }
                                }
                        }
                }
        }
out:
        mutex_exit(&device->gld_devlock);
        mutex_exit(&gld_device_list.gld_devlock);
        return (devinfo);
}

/*
 * STREAMS open routine.  The device dependent driver specifies this as its
 * open entry point.
 */
/*ARGSUSED2*/
int
gld_open(queue_t *q, dev_t *dev, int flag, int sflag, cred_t *cred)
{
        gld_mac_pvt_t *mac_pvt;
        gld_t *gld;
        glddev_t *glddev;
        gld_mac_info_t *macinfo;
        minor_t minor = getminor(*dev);
        gld_vlan_t *vlan;
        t_uscalar_t ppa;

        ASSERT(q != NULL);

        if (minor > GLD_MAX_STYLE1_MINOR)
                return (ENXIO);

        ASSERT(q->q_ptr == NULL);       /* Clone device gives us a fresh Q */

        /* Find our per-major glddev_t structure */
        mutex_enter(&gld_device_list.gld_devlock);
        glddev = gld_devlookup(getmajor(*dev));

        /*
         * This glddev will hang around since detach (and therefore
         * gld_unregister) can't run while we're here in the open routine.
         */
        mutex_exit(&gld_device_list.gld_devlock);

        if (glddev == NULL)
                return (ENXIO);

#ifdef GLD_DEBUG
        if (gld_debug & GLDPROT) {
                if (minor == GLD_USE_STYLE2)
                        cmn_err(CE_NOTE, "gld_open(%p, Style 2)", (void *)q);
                else
                        cmn_err(CE_NOTE, "gld_open(%p, Style 1, minor = %d)",
                            (void *)q, minor);
        }
#endif

        /*
         * get a per-stream structure and link things together so we
         * can easily find them later.
         */
        gld = kmem_zalloc(sizeof (gld_t), KM_SLEEP);

        /*
         * fill in the structure and state info
         */
        gld->gld_qptr = q;
        gld->gld_device = glddev;
        gld->gld_state = DL_UNATTACHED;

        /*
         * we must atomically find a free minor number and add the stream
         * to a list, because gld_findminor has to traverse the lists to
         * determine which minor numbers are free.
         */
        mutex_enter(&glddev->gld_devlock);

        /* find a free minor device number for the clone */
        gld->gld_minor = gld_findminor(glddev);
        if (gld->gld_minor == 0) {
                mutex_exit(&glddev->gld_devlock);
                kmem_free(gld, sizeof (gld_t));
                return (ENOSR);
        }

#ifdef GLD_VERBOSE_DEBUG
        if (gld_debug & GLDPROT)
                cmn_err(CE_NOTE, "gld_open() gld ptr: %p minor: %d",
                    (void *)gld, gld->gld_minor);
#endif

        if (minor == GLD_USE_STYLE2) {
                gld->gld_style = DL_STYLE2;
                *dev = makedevice(getmajor(*dev), gld->gld_minor);
                WR(q)->q_ptr = q->q_ptr = (caddr_t)gld;
                gldinsque(gld, glddev->gld_str_prev);
#ifdef GLD_VERBOSE_DEBUG
                if (gld_debug & GLDPROT)
                        cmn_err(CE_NOTE, "GLDstruct added to device list");
#endif
                (void) qassociate(q, -1);
                goto done;
        }

        gld->gld_style = DL_STYLE1;

        /* the PPA is actually 1 less than the minordev */
        ppa = GLD_STYLE1_MINOR_TO_PPA(minor);

        for (macinfo = glddev->gld_mac_next;
            macinfo != (gld_mac_info_t *)(&glddev->gld_mac_next);
            macinfo = macinfo->gldm_next) {
                ASSERT(macinfo != NULL);
                if (macinfo->gldm_ppa != ppa)
                        continue;

                if (!(macinfo->gldm_GLD_flags & GLD_MAC_READY))
                        continue;       /* this one's not ready yet */

                /*
                 * we found the correct PPA
                 */
                GLDM_LOCK(macinfo, RW_WRITER);

                gld->gld_mac_info = macinfo;

                if (macinfo->gldm_send_tagged != NULL)
                        gld->gld_send = macinfo->gldm_send_tagged;
                else
                        gld->gld_send = macinfo->gldm_send;

                /* now ready for action */
                gld->gld_state = DL_UNBOUND;

                if ((vlan = gld_get_vlan(macinfo, VLAN_VID_NONE)) == NULL) {
                        GLDM_UNLOCK(macinfo);
                        mutex_exit(&glddev->gld_devlock);
                        kmem_free(gld, sizeof (gld_t));
                        return (EIO);
                }

                mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
                if (!mac_pvt->started) {
                        if (gld_start_mac(macinfo) != GLD_SUCCESS) {
                                gld_rem_vlan(vlan);
                                GLDM_UNLOCK(macinfo);
                                mutex_exit(&glddev->gld_devlock);
                                kmem_free(gld, sizeof (gld_t));
                                return (EIO);
                        }
                }

                gld->gld_vlan = vlan;
                vlan->gldv_nstreams++;
                gldinsque(gld, vlan->gldv_str_prev);
                *dev = makedevice(getmajor(*dev), gld->gld_minor);
                WR(q)->q_ptr = q->q_ptr = (caddr_t)gld;

                GLDM_UNLOCK(macinfo);
#ifdef GLD_VERBOSE_DEBUG
                if (gld_debug & GLDPROT)
                        cmn_err(CE_NOTE,
                            "GLDstruct added to instance list");
#endif
                break;
        }

        if (gld->gld_state == DL_UNATTACHED) {
                mutex_exit(&glddev->gld_devlock);
                kmem_free(gld, sizeof (gld_t));
                return (ENXIO);
        }

done:
        mutex_exit(&glddev->gld_devlock);
        noenable(WR(q));        /* We'll do the qenables manually */
        qprocson(q);            /* start the queues running */
        qenable(WR(q));
        return (0);
}

/*
 * normal stream close call checks current status and cleans up
 * data structures that were dynamically allocated
 */
/*ARGSUSED1*/
int
gld_close(queue_t *q, int flag, cred_t *cred)
{
        gld_t   *gld = (gld_t *)q->q_ptr;
        glddev_t *glddev = gld->gld_device;

        ASSERT(q);
        ASSERT(gld);

#ifdef GLD_DEBUG
        if (gld_debug & GLDPROT) {
                cmn_err(CE_NOTE, "gld_close(%p, Style %d)",
                    (void *)q, (gld->gld_style & 0x1) + 1);
        }
#endif

        /* Hold all device streams lists still while we check for a macinfo */
        mutex_enter(&glddev->gld_devlock);

        if (gld->gld_mac_info != NULL) {
                /* If there's a macinfo, block recv while we change state */
                GLDM_LOCK(gld->gld_mac_info, RW_WRITER);
                gld->gld_flags |= GLD_STR_CLOSING; /* no more rcv putnexts */
                GLDM_UNLOCK(gld->gld_mac_info);
        } else {
                /* no mac DL_ATTACHED right now */
                gld->gld_flags |= GLD_STR_CLOSING;
        }

        mutex_exit(&glddev->gld_devlock);

        /*
         * qprocsoff before we call gld_unbind/gldunattach, so that
         * we know wsrv isn't in there trying to undo what we're doing.
         */
        qprocsoff(q);

        ASSERT(gld->gld_wput_count == 0);
        gld->gld_wput_count = 0;        /* just in case */

        if (gld->gld_state == DL_IDLE) {
                /* Need to unbind */
                ASSERT(gld->gld_mac_info != NULL);
                (void) gld_unbind(WR(q), NULL);
        }

        if (gld->gld_state == DL_UNBOUND) {
                /*
                 * Need to unattach
                 * For style 2 stream, gldunattach also
                 * associate queue with NULL dip
                 */
                ASSERT(gld->gld_mac_info != NULL);
                (void) gldunattach(WR(q), NULL);
        }

        /* disassociate the stream from the device */
        q->q_ptr = WR(q)->q_ptr = NULL;

        /*
         * Since we unattached above (if necessary), we know that we're
         * on the per-major list of unattached streams, rather than a
         * per-PPA list.  So we know we should hold the devlock.
         */
        mutex_enter(&glddev->gld_devlock);
        gldremque(gld);                 /* remove from Style 2 list */
        mutex_exit(&glddev->gld_devlock);

        kmem_free(gld, sizeof (gld_t));

        return (0);
}

/*
 * gld_rsrv (q)
 *      simple read service procedure
 *      purpose is to avoid the time it takes for packets
 *      to move through IP so we can get them off the board
 *      as fast as possible due to limited PC resources.
 *
 *      This is not normally used in the current implementation.  It
 *      can be selected with the undocumented property "fast_recv".
 *      If that property is set, gld_recv will send the packet
 *      upstream with a putq() rather than a putnext(), thus causing
 *      this routine to be scheduled.
 */
int
gld_rsrv(queue_t *q)
{
        mblk_t *mp;

        while ((mp = getq(q)) != NULL) {
                if (canputnext(q)) {
                        putnext(q, mp);
                } else {
                        freemsg(mp);
                }
        }
        return (0);
}

/*
 * gld_wput (q, mp)
 * general gld stream write put routine. Receives fastpath data from upper
 * modules and processes it immediately.  ioctl and M_PROTO/M_PCPROTO are
 * queued for later processing by the service procedure.
 */

int
gld_wput(queue_t *q, mblk_t *mp)
{
        gld_t  *gld = (gld_t *)(q->q_ptr);
        int     rc;
        boolean_t multidata = B_TRUE;
        uint32_t upri;

#ifdef GLD_DEBUG
        if (gld_debug & GLDTRACE)
                cmn_err(CE_NOTE, "gld_wput(%p %p): type %x",
                    (void *)q, (void *)mp, DB_TYPE(mp));
#endif
        switch (DB_TYPE(mp)) {

        case M_DATA:
                /* fast data / raw support */
                /* we must be DL_ATTACHED and DL_BOUND to do this */
                /* Tricky to access memory without taking the mutex */
                if ((gld->gld_flags & (GLD_RAW | GLD_FAST)) == 0 ||
                    gld->gld_state != DL_IDLE) {
                        merror(q, mp, EPROTO);
                        break;
                }
                /*
                 * Cleanup MBLK_VTAG in case it is set by other
                 * modules. MBLK_VTAG is used to save the vtag information.
                 */
                GLD_CLEAR_MBLK_VTAG(mp);
                multidata = B_FALSE;
                /* FALLTHROUGH */
        case M_MULTIDATA:
                /* Only call gld_start() directly if nothing queued ahead */
                /* No guarantees about ordering with different threads */
                if (q->q_first)
                        goto use_wsrv;

                /*
                 * This can happen if wsrv has taken off the last mblk but
                 * is still processing it.
                 */
                membar_consumer();
                if (gld->gld_in_wsrv)
                        goto use_wsrv;

                /*
                 * Keep a count of current wput calls to start.
                 * Nonzero count delays any attempted DL_UNBIND.
                 * See comments above gld_start().
                 */
                atomic_inc_32((uint32_t *)&gld->gld_wput_count);
                membar_enter();

                /* Recheck state now wput_count is set to prevent DL_UNBIND */
                /* If this Q is in process of DL_UNBIND, don't call start */
                if (gld->gld_state != DL_IDLE || gld->gld_in_unbind) {
                        /* Extremely unlikely */
                        atomic_dec_32((uint32_t *)&gld->gld_wput_count);
                        goto use_wsrv;
                }

                /*
                 * Get the priority value. Note that in raw mode, the
                 * per-packet priority value kept in b_band is ignored.
                 */
                upri = (gld->gld_flags & GLD_RAW) ? gld->gld_upri :
                    UPRI(gld, mp->b_band);

                rc = (multidata) ? gld_start_mdt(q, mp, GLD_WPUT) :
                    gld_start(q, mp, GLD_WPUT, upri);

                /* Allow DL_UNBIND again */
                membar_exit();
                atomic_dec_32((uint32_t *)&gld->gld_wput_count);

                if (rc == GLD_NORESOURCES)
                        qenable(q);
                break;  /*  Done with this packet */

use_wsrv:
                /* Q not empty, in DL_DETACH, or start gave NORESOURCES */
                (void) putq(q, mp);
                qenable(q);
                break;

        case M_IOCTL:
                /* ioctl relies on wsrv single threading per queue */
                (void) putq(q, mp);
                qenable(q);
                break;

        case M_CTL:
                (void) putq(q, mp);
                qenable(q);
                break;

        case M_FLUSH:           /* canonical flush handling */
                /* XXX Should these be FLUSHALL? */
                if (*mp->b_rptr & FLUSHW)
                        flushq(q, 0);
                if (*mp->b_rptr & FLUSHR) {
                        flushq(RD(q), 0);
                        *mp->b_rptr &= ~FLUSHW;
                        qreply(q, mp);
                } else
                        freemsg(mp);
                break;

        case M_PROTO:
        case M_PCPROTO:
                /* these rely on wsrv single threading per queue */
                (void) putq(q, mp);
                qenable(q);
                break;

        default:
#ifdef GLD_DEBUG
                if (gld_debug & GLDETRACE)
                        cmn_err(CE_WARN,
                            "gld: Unexpected packet type from queue: 0x%x",
                            DB_TYPE(mp));
#endif
                freemsg(mp);
        }
        return (0);
}

/*
 * gld_wsrv - Incoming messages are processed according to the DLPI protocol
 * specification.
 *
 * wsrv is single-threaded per Q.  We make use of this to avoid taking the
 * lock for reading data items that are only ever written by us.
 */

int
gld_wsrv(queue_t *q)
{
        mblk_t *mp;
        gld_t *gld = (gld_t *)q->q_ptr;
        gld_mac_info_t *macinfo;
        union DL_primitives *prim;
        int err;
        boolean_t multidata;
        uint32_t upri;

#ifdef GLD_DEBUG
        if (gld_debug & GLDTRACE)
                cmn_err(CE_NOTE, "gld_wsrv(%p)", (void *)q);
#endif

        ASSERT(!gld->gld_in_wsrv);

        gld->gld_xwait = B_FALSE; /* We are now going to process this Q */

        if (q->q_first == NULL)
                return (0);

        macinfo = gld->gld_mac_info;

        /*
         * Help wput avoid a call to gld_start if there might be a message
         * previously queued by that thread being processed here.
         */
        gld->gld_in_wsrv = B_TRUE;
        membar_enter();

        while ((mp = getq(q)) != NULL) {
                switch (DB_TYPE(mp)) {
                case M_DATA:
                case M_MULTIDATA:
                        multidata = (DB_TYPE(mp) == M_MULTIDATA);

                        /*
                         * retry of a previously processed UNITDATA_REQ
                         * or is a RAW or FAST message from above.
                         */
                        if (macinfo == NULL) {
                                /* No longer attached to a PPA, drop packet */
                                freemsg(mp);
                                break;
                        }

                        gld->gld_sched_ran = B_FALSE;
                        membar_enter();

                        /*
                         * Get the priority value. Note that in raw mode, the
                         * per-packet priority value kept in b_band is ignored.
                         */
                        upri = (gld->gld_flags & GLD_RAW) ? gld->gld_upri :
                            UPRI(gld, mp->b_band);

                        err = (multidata) ? gld_start_mdt(q, mp, GLD_WSRV) :
                            gld_start(q, mp, GLD_WSRV, upri);
                        if (err == GLD_NORESOURCES) {
                                /* gld_sched will qenable us later */
                                gld->gld_xwait = B_TRUE; /* want qenable */
                                membar_enter();
                                /*
                                 * v2:  we're not holding the lock; it's
                                 * possible that the driver could have already
                                 * called gld_sched (following up on its
                                 * return of GLD_NORESOURCES), before we got a
                                 * chance to do the putbq() and set gld_xwait.
                                 * So if we saw a call to gld_sched that
                                 * examined this queue, since our call to
                                 * gld_start() above, then it's possible we've
                                 * already seen the only call to gld_sched()
                                 * we're ever going to see.  So we better retry
                                 * transmitting this packet right now.
                                 */
                                if (gld->gld_sched_ran) {
#ifdef GLD_DEBUG
                                        if (gld_debug & GLDTRACE)
                                                cmn_err(CE_NOTE, "gld_wsrv: "
                                                    "sched was called");
#endif
                                        break;  /* try again right now */
                                }
                                gld->gld_in_wsrv = B_FALSE;
                                return (0);
                        }
                        break;

                case M_IOCTL:
                        (void) gld_ioctl(q, mp);
                        break;

                case M_CTL:
                        if (macinfo == NULL) {
                                freemsg(mp);
                                break;
                        }

                        if (macinfo->gldm_mctl != NULL) {
                                GLDM_LOCK(macinfo, RW_WRITER);
                                (void) (*macinfo->gldm_mctl) (macinfo, q, mp);
                                GLDM_UNLOCK(macinfo);
                        } else {
                                /* This driver doesn't recognize, just drop */
                                freemsg(mp);
                        }
                        break;

                case M_PROTO:   /* Will be an DLPI message of some type */
                case M_PCPROTO:
                        if ((err = gld_cmds(q, mp)) != GLDE_OK) {
                                if (err == GLDE_RETRY) {
                                        gld->gld_in_wsrv = B_FALSE;
                                        return (0); /* quit while we're ahead */
                                }
                                prim = (union DL_primitives *)mp->b_rptr;
                                dlerrorack(q, mp, prim->dl_primitive, err, 0);
                        }
                        break;

                default:
                        /* This should never happen */
#ifdef GLD_DEBUG
                        if (gld_debug & GLDERRS)
                                cmn_err(CE_WARN,
                                    "gld_wsrv: db_type(%x) not supported",
                                    mp->b_datap->db_type);
#endif
                        freemsg(mp);    /* unknown types are discarded */
                        break;
                }
        }

        membar_exit();
        gld->gld_in_wsrv = B_FALSE;
        return (0);
}

/*
 * gld_start() can get called from gld_wput(), gld_wsrv(), or gld_unitdata().
 *
 * We only come directly from wput() in the GLD_FAST (fastpath) or RAW case.
 *
 * In particular, we must avoid calling gld_precv*() if we came from wput().
 * gld_precv*() is where we, on the transmit side, loop back our outgoing
 * packets to the receive side if we are in physical promiscuous mode.
 * Since the receive side holds a lock across its call to the upstream
 * putnext, and that upstream module could well have looped back to our
 * wput() routine on the same thread, we cannot call gld_precv* from here
 * for fear of causing a recursive lock entry in our receive code.
 *
 * There is a problem here when coming from gld_wput().  While wput
 * only comes here if the queue is attached to a PPA and bound to a SAP
 * and there are no messages on the queue ahead of the M_DATA that could
 * change that, it is theoretically possible that another thread could
 * now wput a DL_UNBIND and a DL_DETACH message, and the wsrv() routine
 * could wake up and process them, before we finish processing this
 * send of the M_DATA.  This can only possibly happen on a Style 2 RAW or
 * FAST (fastpath) stream:  non RAW/FAST streams always go through wsrv(),
 * and Style 1 streams only DL_DETACH in the close routine, where
 * qprocsoff() protects us.  If this happens we could end up calling
 * gldm_send() after we have detached the stream and possibly called
 * gldm_stop().  Worse, once the number of attached streams goes to zero,
 * detach/unregister could be called, and the macinfo could go away entirely.
 *
 * No one has ever seen this happen.
 *
 * It is some trouble to fix this, and we would rather not add any mutex
 * logic into the wput() routine, which is supposed to be a "fast"
 * path.
 *
 * What I've done is use an atomic counter to keep a count of the number
 * of threads currently calling gld_start() from wput() on this stream.
 * If DL_DETACH sees this as nonzero, it putbqs the request back onto
 * the queue and qenables, hoping to have better luck next time.  Since
 * people shouldn't be trying to send after they've asked to DL_DETACH,
 * hopefully very soon all the wput=>start threads should have returned
 * and the DL_DETACH will succeed.  It's hard to test this since the odds
 * of the failure even trying to happen are so small.  I probably could
 * have ignored the whole issue and never been the worse for it.
 *
 * Because some GLDv2 Ethernet drivers do not allow the size of transmitted
 * packet to be greater than ETHERMAX, we must first strip the VLAN tag
 * from a tagged packet before passing it to the driver's gld_send() entry
 * point function, and pass the VLAN tag as a separate argument. The
 * gld_send() function may fail. In that case, the packet will need to be
 * queued in order to be processed again in GLD's service routine. As the
 * VTAG has already been stripped at that time, we save the VTAG information
 * in (the unused fields of) dblk using GLD_SAVE_MBLK_VTAG(), so that the
 * VTAG can also be queued and be able to be got when gld_start() is called
 * next time from gld_wsrv().
 *
 * Some rules to use GLD_{CLEAR|SAVE}_MBLK_VTAG macros:
 *
 * - GLD_SAVE_MBLK_VTAG() must be called to save the VTAG information each time
 *   the message is queued by putbq().
 *
 * - GLD_CLEAR_MBLK_VTAG() must be called to clear the bogus VTAG information
 *   (if any) in dblk before the message is passed to the gld_start() function.
 */
static int
gld_start(queue_t *q, mblk_t *mp, int caller, uint32_t upri)
{
        mblk_t *nmp;
        gld_t *gld = (gld_t *)q->q_ptr;
        gld_mac_info_t *macinfo;
        gld_mac_pvt_t *mac_pvt;
        int rc;
        gld_interface_t *ifp;
        pktinfo_t pktinfo;
        uint32_t vtag, vid;
        uint32_t raw_vtag = 0;
        gld_vlan_t *vlan;
        struct gld_stats *stats0, *stats = NULL;

        ASSERT(DB_TYPE(mp) == M_DATA);
        macinfo = gld->gld_mac_info;
        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        ifp = mac_pvt->interfacep;
        vlan = (gld_vlan_t *)gld->gld_vlan;
        vid = vlan->gldv_id;

        /*
         * If this interface is a VLAN, the kstats of corresponding
         * "VLAN 0" should also be updated. Note that the gld_vlan_t
         * structure for VLAN 0 might not exist if there are no DLPI
         * consumers attaching on VLAN 0. Fortunately we can directly
         * access VLAN 0's kstats from macinfo.
         *
         * Therefore, stats0 (VLAN 0's kstats) must always be
         * updated, and stats must to be updated if it is not NULL.
         */
        stats0 = mac_pvt->statistics;
        if (vid != VLAN_VID_NONE)
                stats = vlan->gldv_stats;

        if ((*ifp->interpreter)(macinfo, mp, &pktinfo, GLD_TX) != 0) {
#ifdef GLD_DEBUG
                if (gld_debug & GLDERRS)
                        cmn_err(CE_WARN,
                            "gld_start: failed to interpret outbound packet");
#endif
                goto badarg;
        }

        vtag = VLAN_VID_NONE;
        raw_vtag = GLD_GET_MBLK_VTAG(mp);
        if (GLD_VTAG_TCI(raw_vtag) != 0) {
                uint16_t raw_pri, raw_vid, evid;

                /*
                 * Tagged packet.
                 */
                raw_pri = GLD_VTAG_PRI(raw_vtag);
                raw_vid = GLD_VTAG_VID(raw_vtag);
                GLD_CLEAR_MBLK_VTAG(mp);

                if (gld->gld_flags & GLD_RAW) {
                        /*
                         * In raw mode, we only expect untagged packets or
                         * special priority-tagged packets on a VLAN stream.
                         * Drop the packet if its VID is not zero.
                         */
                        if (vid != VLAN_VID_NONE && raw_vid != VLAN_VID_NONE)
                                goto badarg;

                        /*
                         * If it is raw mode, use the per-stream priority if
                         * the priority is not specified in the packet.
                         * Otherwise, ignore the priority bits in the packet.
                         */
                        upri = (raw_pri != 0) ? raw_pri : upri;
                }

                if (vid == VLAN_VID_NONE && vid != raw_vid) {
                        gld_vlan_t *tmp_vlan;

                        /*
                         * This link is a physical link but the packet is
                         * a VLAN tagged packet, the kstats of corresponding
                         * VLAN (if any) should also be updated.
                         */
                        tmp_vlan = gld_find_vlan(macinfo, raw_vid);
                        if (tmp_vlan != NULL)
                                stats = tmp_vlan->gldv_stats;
                }

                evid = (vid == VLAN_VID_NONE) ? raw_vid : vid;
                if (evid != VLAN_VID_NONE || upri != 0)
                        vtag = GLD_MAKE_VTAG(upri, VLAN_CFI_ETHER, evid);
        } else {
                /*
                 * Untagged packet:
                 * Get vtag from the attached PPA of this stream.
                 */
                if ((vid != VLAN_VID_NONE) ||
                    ((macinfo->gldm_type == DL_ETHER) && (upri != 0))) {
                        vtag = GLD_MAKE_VTAG(upri, VLAN_CFI_ETHER, vid);
                }
        }

        /*
         * We're not holding the lock for this check.  If the promiscuous
         * state is in flux it doesn't matter much if we get this wrong.
         */
        if (mac_pvt->nprom > 0) {
                /*
                 * We want to loopback to the receive side, but to avoid
                 * recursive lock entry:  if we came from wput(), which
                 * could have looped back via IP from our own receive
                 * interrupt thread, we decline this request.  wput()
                 * will then queue the packet for wsrv().  This means
                 * that when snoop is running we don't get the advantage
                 * of the wput() multithreaded direct entry to the
                 * driver's send routine.
                 */
                if (caller == GLD_WPUT) {
                        GLD_SAVE_MBLK_VTAG(mp, raw_vtag);
                        (void) putbq(q, mp);
                        return (GLD_NORESOURCES);
                }
                if (macinfo->gldm_capabilities & GLD_CAP_ZEROCOPY)
                        nmp = dupmsg_noloan(mp);
                else
                        nmp = dupmsg(mp);
        } else
                nmp = NULL;             /* we need no loopback */

        if (ifp->hdr_size > 0 &&
            pktinfo.pktLen > ifp->hdr_size + (vtag == 0 ? 0 : VTAG_SIZE) +
            macinfo->gldm_maxpkt) {
                if (nmp)
                        freemsg(nmp);   /* free the duped message */
#ifdef GLD_DEBUG
                if (gld_debug & GLDERRS)
                        cmn_err(CE_WARN,
                            "gld_start: oversize outbound packet, size %d,"
                            "max %d", pktinfo.pktLen,
                            ifp->hdr_size + (vtag == 0 ? 0 : VTAG_SIZE) +
                            macinfo->gldm_maxpkt);
#endif
                goto badarg;
        }

        rc = (*gld->gld_send)(macinfo, mp, vtag);

        if (rc != GLD_SUCCESS) {
                if (rc == GLD_NORESOURCES) {
                        ATOMIC_BUMP(stats0, stats, glds_xmtretry, 1);
                        GLD_SAVE_MBLK_VTAG(mp, raw_vtag);
                        (void) putbq(q, mp);
                } else {
                        /* transmit error; drop the packet */
                        freemsg(mp);
                        /* We're supposed to count failed attempts as well */
                        UPDATE_STATS(stats0, stats, pktinfo, 1);
#ifdef GLD_DEBUG
                        if (gld_debug & GLDERRS)
                                cmn_err(CE_WARN,
                                    "gld_start: gldm_send failed %d", rc);
#endif
                }
                if (nmp)
                        freemsg(nmp);   /* free the dupped message */
                return (rc);
        }

        UPDATE_STATS(stats0, stats, pktinfo, 1);

        /*
         * Loopback case. The message needs to be returned back on
         * the read side. This would silently fail if the dupmsg fails
         * above. This is probably OK, if there is no memory to dup the
         * block, then there isn't much we could do anyway.
         */
        if (nmp) {
                GLDM_LOCK(macinfo, RW_WRITER);
                gld_precv(macinfo, nmp, vtag, stats);
                GLDM_UNLOCK(macinfo);
        }

        return (GLD_SUCCESS);
badarg:
        freemsg(mp);

        ATOMIC_BUMP(stats0, stats, glds_xmtbadinterp, 1);
        return (GLD_BADARG);
}

/*
 * With MDT V.2 a single message mp can have one header area and multiple
 * payload areas. A packet is described by dl_pkt_info, and each packet can
 * span multiple payload areas (currently with TCP, each packet will have one
 * header and at the most two payload areas). MACs might have a limit on the
 * number of payload segments (i.e. per packet scatter-gather limit), and
 * MDT V.2 has a way of specifying that with mdt_span_limit; the MAC driver
 * might also have a limit on the total number of payloads in a message, and
 * that is specified by mdt_max_pld.
 */
static int
gld_start_mdt(queue_t *q, mblk_t *mp, int caller)
{
        mblk_t *nextmp;
        gld_t *gld = (gld_t *)q->q_ptr;
        gld_mac_info_t *macinfo = gld->gld_mac_info;
        gld_mac_pvt_t *mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        int numpacks, mdtpacks;
        gld_interface_t *ifp = mac_pvt->interfacep;
        pktinfo_t pktinfo;
        gld_vlan_t *vlan = (gld_vlan_t *)gld->gld_vlan;
        boolean_t doloop = B_FALSE;
        multidata_t *dlmdp;
        pdescinfo_t pinfo;
        pdesc_t *dl_pkt;
        void *cookie;
        uint_t totLen = 0;

        ASSERT(DB_TYPE(mp) == M_MULTIDATA);

        /*
         * We're not holding the lock for this check.  If the promiscuous
         * state is in flux it doesn't matter much if we get this wrong.
         */
        if (mac_pvt->nprom > 0) {
                /*
                 * We want to loopback to the receive side, but to avoid
                 * recursive lock entry:  if we came from wput(), which
                 * could have looped back via IP from our own receive
                 * interrupt thread, we decline this request.  wput()
                 * will then queue the packet for wsrv().  This means
                 * that when snoop is running we don't get the advantage
                 * of the wput() multithreaded direct entry to the
                 * driver's send routine.
                 */
                if (caller == GLD_WPUT) {
                        (void) putbq(q, mp);
                        return (GLD_NORESOURCES);
                }
                doloop = B_TRUE;

                /*
                 * unlike the M_DATA case, we don't have to call
                 * dupmsg_noloan here because mmd_transform
                 * (called by gld_precv_mdt) will make a copy of
                 * each dblk.
                 */
        }

        while (mp != NULL) {
                /*
                 * The lower layer driver only gets a single multidata
                 * message; this also makes it easier to handle noresources.
                 */
                nextmp = mp->b_cont;
                mp->b_cont = NULL;

                /*
                 * Get number of packets in this message; if nothing
                 * to transmit, go to next message.
                 */
                dlmdp = mmd_getmultidata(mp);
                if ((mdtpacks = (int)mmd_getcnt(dlmdp, NULL, NULL)) == 0) {
                        freemsg(mp);
                        mp = nextmp;
                        continue;
                }

                /*
                 * Run interpreter to populate media specific pktinfo fields.
                 * This collects per MDT message information like sap,
                 * broad/multicast etc.
                 */
                (void) (*ifp->interpreter_mdt)(macinfo, mp, NULL, &pktinfo,
                    GLD_MDT_TX);

                numpacks = (*macinfo->gldm_mdt_pre)(macinfo, mp, &cookie);

                if (numpacks > 0) {
                        /*
                         * Driver indicates it can transmit at least 1, and
                         * possibly all, packets in MDT message.
                         */
                        int count = numpacks;

                        for (dl_pkt = mmd_getfirstpdesc(dlmdp, &pinfo);
                            (dl_pkt != NULL);
                            dl_pkt = mmd_getnextpdesc(dl_pkt, &pinfo)) {
                                /*
                                 * Format this packet by adding link header and
                                 * adjusting pdescinfo to include it; get
                                 * packet length.
                                 */
                                (void) (*ifp->interpreter_mdt)(macinfo, NULL,
                                    &pinfo, &pktinfo, GLD_MDT_TXPKT);

                                totLen += pktinfo.pktLen;

                                /*
                                 * Loop back packet before handing to the
                                 * driver.
                                 */
                                if (doloop &&
                                    mmd_adjpdesc(dl_pkt, &pinfo) != NULL) {
                                        GLDM_LOCK(macinfo, RW_WRITER);
                                        gld_precv_mdt(macinfo, vlan, mp,
                                            dl_pkt, &pktinfo);
                                        GLDM_UNLOCK(macinfo);
                                }

                                /*
                                 * And send off to driver.
                                 */
                                (*macinfo->gldm_mdt_send)(macinfo, cookie,
                                    &pinfo);

                                /*
                                 * Be careful not to invoke getnextpdesc if we
                                 * already sent the last packet, since driver
                                 * might have posted it to hardware causing a
                                 * completion and freemsg() so the MDT data
                                 * structures might not be valid anymore.
                                 */
                                if (--count == 0)
                                        break;
                        }
                        (*macinfo->gldm_mdt_post)(macinfo, mp, cookie);
                        pktinfo.pktLen = totLen;
                        UPDATE_STATS(vlan->gldv_stats, NULL, pktinfo, numpacks);

                        /*
                         * In the noresources case (when driver indicates it
                         * can not transmit all packets in the MDT message),
                         * adjust to skip the first few packets on retrial.
                         */
                        if (numpacks != mdtpacks) {
                                /*
                                 * Release already processed packet descriptors.
                                 */
                                for (count = 0; count < numpacks; count++) {
                                        dl_pkt = mmd_getfirstpdesc(dlmdp,
                                            &pinfo);
                                        mmd_rempdesc(dl_pkt);
                                }
                                ATOMIC_BUMP(vlan->gldv_stats, NULL,
                                    glds_xmtretry, 1);
                                mp->b_cont = nextmp;
                                (void) putbq(q, mp);
                                return (GLD_NORESOURCES);
                        }
                } else if (numpacks == 0) {
                        /*
                         * Driver indicates it can not transmit any packets
                         * currently and will request retrial later.
                         */
                        ATOMIC_BUMP(vlan->gldv_stats, NULL, glds_xmtretry, 1);
                        mp->b_cont = nextmp;
                        (void) putbq(q, mp);
                        return (GLD_NORESOURCES);
                } else {
                        ASSERT(numpacks == -1);
                        /*
                         * We're supposed to count failed attempts as well.
                         */
                        dl_pkt = mmd_getfirstpdesc(dlmdp, &pinfo);
                        while (dl_pkt != NULL) {
                                /*
                                 * Call interpreter to determine total packet
                                 * bytes that are being dropped.
                                 */
                                (void) (*ifp->interpreter_mdt)(macinfo, NULL,
                                    &pinfo, &pktinfo, GLD_MDT_TXPKT);

                                totLen += pktinfo.pktLen;

                                dl_pkt = mmd_getnextpdesc(dl_pkt, &pinfo);
                        }
                        pktinfo.pktLen = totLen;
                        UPDATE_STATS(vlan->gldv_stats, NULL, pktinfo, mdtpacks);

                        /*
                         * Transmit error; drop the message, move on
                         * to the next one.
                         */
                        freemsg(mp);
                }

                /*
                 * Process the next multidata block, if there is one.
                 */
                mp = nextmp;
        }

        return (GLD_SUCCESS);
}

/*
 * gld_intr (macinfo)
 */
uint_t
gld_intr(gld_mac_info_t *macinfo)
{
        ASSERT(macinfo != NULL);

        if (!(macinfo->gldm_GLD_flags & GLD_MAC_READY))
                return (DDI_INTR_UNCLAIMED);

        return ((*macinfo->gldm_intr)(macinfo));
}

/*
 * gld_sched (macinfo)
 *
 * This routine scans the streams that refer to a specific macinfo
 * structure and causes the STREAMS scheduler to try to run them if
 * they are marked as waiting for the transmit buffer.
 */
void
gld_sched(gld_mac_info_t *macinfo)
{
        gld_mac_pvt_t *mac_pvt;
        gld_t *gld;
        gld_vlan_t *vlan;
        int i;

        ASSERT(macinfo != NULL);

        GLDM_LOCK(macinfo, RW_WRITER);

        if (macinfo->gldm_GLD_flags & GLD_UNREGISTERED) {
                /* We're probably being called from a leftover interrupt */
                GLDM_UNLOCK(macinfo);
                return;
        }

        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;

        for (i = 0; i < VLAN_HASHSZ; i++) {
                for (vlan = mac_pvt->vlan_hash[i];
                    vlan != NULL; vlan = vlan->gldv_next) {
                        for (gld = vlan->gldv_str_next;
                            gld != (gld_t *)&vlan->gldv_str_next;
                            gld = gld->gld_next) {
                                ASSERT(gld->gld_mac_info == macinfo);
                                gld->gld_sched_ran = B_TRUE;
                                membar_enter();
                                if (gld->gld_xwait) {
                                        gld->gld_xwait = B_FALSE;
                                        qenable(WR(gld->gld_qptr));
                                }
                        }
                }
        }

        GLDM_UNLOCK(macinfo);
}

/*
 * gld_precv (macinfo, mp, vtag, stats)
 * called from gld_start to loopback a packet when in promiscuous mode
 *
 * VLAN 0's statistics need to be updated. If stats is not NULL,
 * it needs to be updated as well.
 */
static void
gld_precv(gld_mac_info_t *macinfo, mblk_t *mp, uint32_t vtag,
    struct gld_stats *stats)
{
        gld_mac_pvt_t *mac_pvt;
        gld_interface_t *ifp;
        pktinfo_t pktinfo;

        ASSERT(GLDM_LOCK_HELD_WRITE(macinfo));

        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        ifp = mac_pvt->interfacep;

        /*
         * call the media specific packet interpreter routine
         */
        if ((*ifp->interpreter)(macinfo, mp, &pktinfo, GLD_RXLOOP) != 0) {
                freemsg(mp);
                BUMP(mac_pvt->statistics, stats, glds_rcvbadinterp, 1);
#ifdef GLD_DEBUG
                if (gld_debug & GLDERRS)
                        cmn_err(CE_WARN,
                            "gld_precv: interpreter failed");
#endif
                return;
        }

        /*
         * Update the vtag information.
         */
        pktinfo.isTagged = (vtag != VLAN_VID_NONE);
        pktinfo.vid = GLD_VTAG_VID(vtag);
        pktinfo.cfi = GLD_VTAG_CFI(vtag);
        pktinfo.user_pri = GLD_VTAG_PRI(vtag);

        gld_sendup(macinfo, &pktinfo, mp, gld_paccept);
}

/*
 * Called from gld_start_mdt to loopback packet(s) when in promiscuous mode.
 * Note that 'vlan' is always a physical link, because MDT can only be
 * enabled on non-VLAN streams.
 */
/*ARGSUSED*/
static void
gld_precv_mdt(gld_mac_info_t *macinfo, gld_vlan_t *vlan, mblk_t *mp,
    pdesc_t *dl_pkt, pktinfo_t *pktinfo)
{
        mblk_t *adjmp;
        gld_mac_pvt_t *mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        gld_interface_t *ifp = mac_pvt->interfacep;

        ASSERT(GLDM_LOCK_HELD_WRITE(macinfo));

        /*
         * Get source/destination.
         */
        (void) (*ifp->interpreter_mdt)(macinfo, mp, NULL, pktinfo,
            GLD_MDT_RXLOOP);
        if ((adjmp = mmd_transform(dl_pkt)) != NULL)
                gld_sendup(macinfo, pktinfo, adjmp, gld_paccept);
}

/*
 * gld_recv (macinfo, mp)
 * called with an mac-level packet in a mblock; take the maclock,
 * try the ip4q and ip6q hack, and otherwise call gld_sendup.
 *
 * V0 drivers already are holding the mutex when they call us.
 */
void
gld_recv(gld_mac_info_t *macinfo, mblk_t *mp)
{
        gld_recv_tagged(macinfo, mp, VLAN_VTAG_NONE);
}

void
gld_recv_tagged(gld_mac_info_t *macinfo, mblk_t *mp, uint32_t vtag)
{
        gld_mac_pvt_t *mac_pvt;
        char pbuf[3*GLD_MAX_ADDRLEN];
        pktinfo_t pktinfo;
        gld_interface_t *ifp;
        queue_t *ipq = NULL;
        gld_vlan_t *vlan = NULL, *vlan0 = NULL, *vlann = NULL;
        struct gld_stats *stats0, *stats = NULL;
        uint32_t vid;
        int err;

        ASSERT(macinfo != NULL);
        ASSERT(mp->b_datap->db_ref);

        GLDM_LOCK(macinfo, RW_READER);

        if (macinfo->gldm_GLD_flags & GLD_UNREGISTERED) {
                /* We're probably being called from a leftover interrupt */
                freemsg(mp);
                goto done;
        }

        /*
         * If this packet is a VLAN tagged packet, the kstats of corresponding
         * "VLAN 0" should also be updated. We can directly access VLAN 0's
         * kstats from macinfo.
         *
         * Further, the packets needs to be passed to VLAN 0 if there is
         * any DLPI consumer on VLAN 0 who is interested in tagged packets
         * (DL_PROMISC_SAP is on or is bounded to ETHERTYPE_VLAN SAP).
         */
        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        stats0 = mac_pvt->statistics;

        vid = GLD_VTAG_VID(vtag);
        vlan0 = gld_find_vlan(macinfo, VLAN_VID_NONE);
        if (vid != VLAN_VID_NONE) {
                /*
                 * If there are no physical DLPI consumers interested in the
                 * VLAN packet, clear vlan0.
                 */
                if ((vlan0 != NULL) && (vlan0->gldv_nvlan_sap == 0))
                        vlan0 = NULL;
                /*
                 * vlann is the VLAN with the same VID as the VLAN packet.
                 */
                vlann = gld_find_vlan(macinfo, vid);
                if (vlann != NULL)
                        stats = vlann->gldv_stats;
        }

        vlan = (vid == VLAN_VID_NONE) ? vlan0 : vlann;

        ifp = mac_pvt->interfacep;
        err = (*ifp->interpreter)(macinfo, mp, &pktinfo, GLD_RXQUICK);

        BUMP(stats0, stats, glds_bytercv64, pktinfo.pktLen);
        BUMP(stats0, stats, glds_pktrcv64, 1);

        if ((vlann == NULL) && (vlan0 == NULL)) {
                freemsg(mp);
                goto done;
        }

        /*
         * Check whether underlying media code supports the IPQ hack:
         *
         * - the interpreter could quickly parse the packet
         * - the device type supports IPQ (ethernet and IPoIB)
         * - there is one, and only one, IP stream bound (to this VLAN)
         * - that stream is a "fastpath" stream
         * - the packet is of type ETHERTYPE_IP or ETHERTYPE_IPV6
         * - there are no streams in promiscuous mode (on this VLAN)
         * - if this packet is tagged, there is no need to send this
         *   packet to physical streams
         */
        if ((err != 0) && ((vlan != NULL) && (vlan->gldv_nprom == 0)) &&
            (vlan == vlan0 || vlan0 == NULL)) {
                switch (pktinfo.ethertype) {
                case ETHERTYPE_IP:
                        ipq = vlan->gldv_ipq;
                        break;
                case ETHERTYPE_IPV6:
                        ipq = vlan->gldv_ipv6q;
                        break;
                }
        }

        /*
         * Special case for IP; we can simply do the putnext here, if:
         * o The IPQ hack is possible (ipq != NULL).
         * o the packet is specifically for me, and therefore:
         * - the packet is not multicast or broadcast (fastpath only
         *   wants unicast packets).
         *
         * o the stream is not asserting flow control.
         */
        if (ipq != NULL &&
            pktinfo.isForMe &&
            canputnext(ipq)) {
                /*
                 * Skip the mac header. We know there is no LLC1/SNAP header
                 * in this packet
                 */
                mp->b_rptr += pktinfo.macLen;
                putnext(ipq, mp);
                goto done;
        }

        /*
         * call the media specific packet interpreter routine
         */
        if ((*ifp->interpreter)(macinfo, mp, &pktinfo, GLD_RX) != 0) {
                BUMP(stats0, stats, glds_rcvbadinterp, 1);
#ifdef GLD_DEBUG
                if (gld_debug & GLDERRS)
                        cmn_err(CE_WARN,
                            "gld_recv_tagged: interpreter failed");
#endif
                freemsg(mp);
                goto done;
        }

        /*
         * This is safe even if vtag is VLAN_VTAG_NONE
         */
        pktinfo.vid = vid;
        pktinfo.cfi = GLD_VTAG_CFI(vtag);
#ifdef GLD_DEBUG
        if (pktinfo.cfi != VLAN_CFI_ETHER)
                cmn_err(CE_WARN, "gld_recv_tagged: non-ETHER CFI");
#endif
        pktinfo.user_pri = GLD_VTAG_PRI(vtag);
        pktinfo.isTagged = (vtag != VLAN_VID_NONE);

#ifdef GLD_DEBUG
        if ((gld_debug & GLDRECV) &&
            (!(gld_debug & GLDNOBR) ||
            (!pktinfo.isBroadcast && !pktinfo.isMulticast))) {
                char pbuf2[3*GLD_MAX_ADDRLEN];

                cmn_err(CE_CONT, "gld_recv_tagged: machdr=<%s -> %s>\n",
                    gld_macaddr_sprintf(pbuf, pktinfo.shost,
                    macinfo->gldm_addrlen), gld_macaddr_sprintf(pbuf2,
                    pktinfo.dhost, macinfo->gldm_addrlen));
                cmn_err(CE_CONT, "gld_recv_tagged: VlanId %d UserPri %d\n",
                    pktinfo.vid,
                    pktinfo.user_pri);
                cmn_err(CE_CONT, "gld_recv_tagged: ethertype: %4x Len: %4d "
                    "Hdr: %d,%d isMulticast: %s\n",
                    pktinfo.ethertype,
                    pktinfo.pktLen,
                    pktinfo.macLen,
                    pktinfo.hdrLen,
                    pktinfo.isMulticast ? "Y" : "N");
        }
#endif

        gld_sendup(macinfo, &pktinfo, mp, gld_accept);

done:
        GLDM_UNLOCK(macinfo);
}

/* =================================================================== */
/* receive group: called from gld_recv and gld_precv* with maclock held */
/* =================================================================== */

/*
 * Search all the streams attached to the specified VLAN looking for
 * those eligible to receive the packet.
 * Note that in order to avoid an extra dupmsg(), if this is the first
 * eligible stream, remember it (in fgldp) so that we can send up the
 * message after this function.
 *
 * Return errno if fails. Currently the only error is ENOMEM.
 */
static int
gld_sendup_vlan(gld_vlan_t *vlan, pktinfo_t *pktinfo, mblk_t *mp,
    int (*acceptfunc)(), void (*send)(), int (*cansend)(), gld_t **fgldp)
{
        mblk_t *nmp;
        gld_t *gld;
        int err = 0;

        ASSERT(vlan != NULL);
        for (gld = vlan->gldv_str_next; gld != (gld_t *)&vlan->gldv_str_next;
            gld = gld->gld_next) {
#ifdef GLD_VERBOSE_DEBUG
                cmn_err(CE_NOTE, "gld_sendup_vlan: SAP: %4x QPTR: %p "
                    "QSTATE: %s", gld->gld_sap, (void *)gld->gld_qptr,
                    gld->gld_state == DL_IDLE ? "IDLE" : "NOT IDLE");
#endif
                ASSERT(gld->gld_qptr != NULL);
                ASSERT(gld->gld_state == DL_IDLE ||
                    gld->gld_state == DL_UNBOUND);
                ASSERT(gld->gld_vlan == vlan);

                if (gld->gld_state != DL_IDLE)
                        continue;       /* not eligible to receive */
                if (gld->gld_flags & GLD_STR_CLOSING)
                        continue;       /* not eligible to receive */

#ifdef GLD_DEBUG
                if ((gld_debug & GLDRECV) &&
                    (!(gld_debug & GLDNOBR) ||
                    (!pktinfo->isBroadcast && !pktinfo->isMulticast)))
                        cmn_err(CE_NOTE,
                            "gld_sendup: queue sap: %4x promis: %s %s %s",
                            gld->gld_sap,
                            gld->gld_flags & GLD_PROM_PHYS ? "phys " : "     ",
                            gld->gld_flags & GLD_PROM_SAP  ? "sap  " : "     ",
                            gld->gld_flags & GLD_PROM_MULT ? "multi" : "     ");
#endif

                /*
                 * The accept function differs depending on whether this is
                 * a packet that we received from the wire or a loopback.
                 */
                if ((*acceptfunc)(gld, pktinfo)) {
                        /* sap matches */
                        pktinfo->wasAccepted = 1; /* known protocol */

                        if (!(*cansend)(gld->gld_qptr)) {
                                /*
                                 * Upper stream is not accepting messages, i.e.
                                 * it is flow controlled, therefore we will
                                 * forgo sending the message up this stream.
                                 */
#ifdef GLD_DEBUG
                                if (gld_debug & GLDETRACE)
                                        cmn_err(CE_WARN,
                                            "gld_sendup: canput failed");
#endif
                                BUMP(vlan->gldv_stats, NULL, glds_blocked, 1);
                                qenable(gld->gld_qptr);
                                continue;
                        }

                        /*
                         * In order to avoid an extra dupmsg(), remember this
                         * gld if this is the first eligible stream.
                         */
                        if (*fgldp == NULL) {
                                *fgldp = gld;
                                continue;
                        }

                        /* duplicate the packet for this stream */
                        nmp = dupmsg(mp);
                        if (nmp == NULL) {
                                BUMP(vlan->gldv_stats, NULL,
                                    glds_gldnorcvbuf, 1);
#ifdef GLD_DEBUG
                                if (gld_debug & GLDERRS)
                                        cmn_err(CE_WARN,
                                            "gld_sendup: dupmsg failed");
#endif
                                /* couldn't get resources; drop it */
                                err = ENOMEM;
                                break;
                        }
                        /* pass the message up the stream */
                        gld_passon(gld, nmp, pktinfo, send);
                }
        }
        return (err);
}

/*
 * gld_sendup (macinfo, pktinfo, mp, acceptfunc)
 * called with an ethernet packet in an mblk; must decide whether
 * packet is for us and which streams to queue it to.
 */
static void
gld_sendup(gld_mac_info_t *macinfo, pktinfo_t *pktinfo,
    mblk_t *mp, int (*acceptfunc)())
{
        gld_t *fgld = NULL;
        void (*send)(queue_t *qp, mblk_t *mp);
        int (*cansend)(queue_t *qp);
        gld_vlan_t *vlan0, *vlann = NULL;
        struct gld_stats *stats0, *stats = NULL;
        int err = 0;

#ifdef GLD_DEBUG
        if (gld_debug & GLDTRACE)
                cmn_err(CE_NOTE, "gld_sendup(%p, %p)", (void *)mp,
                    (void *)macinfo);
#endif

        ASSERT(mp != NULL);
        ASSERT(macinfo != NULL);
        ASSERT(pktinfo != NULL);
        ASSERT(GLDM_LOCK_HELD(macinfo));

        /*
         * The tagged packets should also be looped back (transmit-side)
         * or sent up (receive-side) to VLAN 0 if VLAN 0 is set to
         * DL_PROMISC_SAP or there is any DLPI consumer bind to the
         * ETHERTYPE_VLAN SAP. The kstats of VLAN 0 needs to be updated
         * as well.
         */
        stats0 = ((gld_mac_pvt_t *)macinfo->gldm_mac_pvt)->statistics;
        vlan0 = gld_find_vlan(macinfo, VLAN_VID_NONE);
        if (pktinfo->vid != VLAN_VID_NONE) {
                if ((vlan0 != NULL) && (vlan0->gldv_nvlan_sap == 0))
                        vlan0 = NULL;
                vlann = gld_find_vlan(macinfo, pktinfo->vid);
                if (vlann != NULL)
                        stats = vlann->gldv_stats;
        }

        ASSERT((vlan0 != NULL) || (vlann != NULL));

        /*
         * The "fast" in "GLDOPT_FAST_RECV" refers to the speed at which
         * gld_recv returns to the caller's interrupt routine.  The total
         * network throughput would normally be lower when selecting this
         * option, because we putq the messages and process them later,
         * instead of sending them with putnext now.  Some time critical
         * device might need this, so it's here but undocumented.
         */
        if (macinfo->gldm_options & GLDOPT_FAST_RECV) {
                send = (void (*)(queue_t *, mblk_t *))putq;
                cansend = canput;
        } else {
                send = (void (*)(queue_t *, mblk_t *))putnext;
                cansend = canputnext;
        }

        /*
         * Send the packets for all eligible streams.
         */
        if (vlan0 != NULL) {
                err = gld_sendup_vlan(vlan0, pktinfo, mp, acceptfunc, send,
                    cansend, &fgld);
        }
        if ((err == 0) && (vlann != NULL)) {
                err = gld_sendup_vlan(vlann, pktinfo, mp, acceptfunc, send,
                    cansend, &fgld);
        }

        ASSERT(mp);
        /* send the original dup of the packet up the first stream found */
        if (fgld)
                gld_passon(fgld, mp, pktinfo, send);
        else
                freemsg(mp);    /* no streams matched */

        /* We do not count looped back packets */
        if (acceptfunc == gld_paccept)
                return;         /* transmit loopback case */

        if (pktinfo->isBroadcast)
                BUMP(stats0, stats, glds_brdcstrcv, 1);
        else if (pktinfo->isMulticast)
                BUMP(stats0, stats, glds_multircv, 1);

        /* No stream accepted this packet */
        if (!pktinfo->wasAccepted)
                BUMP(stats0, stats, glds_unknowns, 1);
}

#define GLD_IS_PHYS(gld)        \
        (((gld_vlan_t *)gld->gld_vlan)->gldv_id == VLAN_VID_NONE)

/*
 * A packet matches a stream if:
 *      The stream's VLAN id is the same as the one in the packet.
 *  and the stream accepts EtherType encoded packets and the type matches
 *  or  the stream accepts LLC packets and the packet is an LLC packet
 */
#define MATCH(stream, pktinfo) \
        ((((gld_vlan_t *)stream->gld_vlan)->gldv_id == pktinfo->vid) && \
        ((stream->gld_ethertype && stream->gld_sap == pktinfo->ethertype) || \
        (!stream->gld_ethertype && pktinfo->isLLC)))

/*
 * This function validates a packet for sending up a particular
 * stream. The message header has been parsed and its characteristic
 * are recorded in the pktinfo data structure. The streams stack info
 * are presented in gld data structures.
 */
static int
gld_accept(gld_t *gld, pktinfo_t *pktinfo)
{
        /*
         * if there is no match do not bother checking further.
         * Note that it is okay to examine gld_vlan because
         * macinfo->gldm_lock is held.
         *
         * Because all tagged packets have SAP value ETHERTYPE_VLAN,
         * these packets will pass the SAP filter check if the stream
         * is a ETHERTYPE_VLAN listener.
         */
        if ((!MATCH(gld, pktinfo) && !(gld->gld_flags & GLD_PROM_SAP) &&
            !(GLD_IS_PHYS(gld) && gld->gld_sap == ETHERTYPE_VLAN &&
            pktinfo->isTagged)))
                return (0);

        /*
         * We don't accept any packet from the hardware if we originated it.
         * (Contrast gld_paccept, the send-loopback accept function.)
         */
        if (pktinfo->isLooped)
                return (0);

        /*
         * If the packet is broadcast or sent to us directly we will accept it.
         * Also we will accept multicast packets requested by the stream.
         */
        if (pktinfo->isForMe || pktinfo->isBroadcast ||
            gld_mcmatch(gld, pktinfo))
                return (1);

        /*
         * Finally, accept anything else if we're in promiscuous mode
         */
        if (gld->gld_flags & GLD_PROM_PHYS)
                return (1);

        return (0);
}

/*
 * Return TRUE if the given multicast address is one
 * of those that this particular Stream is interested in.
 */
static int
gld_mcmatch(gld_t *gld, pktinfo_t *pktinfo)
{
        /*
         * Return FALSE if not a multicast address.
         */
        if (!pktinfo->isMulticast)
                return (0);

        /*
         * Check if all multicasts have been enabled for this Stream
         */
        if (gld->gld_flags & GLD_PROM_MULT)
                return (1);

        /*
         * Return FALSE if no multicast addresses enabled for this Stream.
         */
        if (!gld->gld_mcast)
                return (0);

        /*
         * Otherwise, look for it in the table.
         */
        return (gld_multicast(pktinfo->dhost, gld));
}

/*
 * gld_multicast determines if the address is a multicast address for
 * this stream.
 */
static int
gld_multicast(unsigned char *macaddr, gld_t *gld)
{
        int i;

        ASSERT(GLDM_LOCK_HELD(gld->gld_mac_info));

        if (!gld->gld_mcast)
                return (0);

        for (i = 0; i < gld->gld_multicnt; i++) {
                if (gld->gld_mcast[i]) {
                        ASSERT(gld->gld_mcast[i]->gldm_refcnt);
                        if (mac_eq(gld->gld_mcast[i]->gldm_addr, macaddr,
                            gld->gld_mac_info->gldm_addrlen))
                                return (1);
                }
        }

        return (0);
}

/*
 * accept function for looped back packets
 */
static int
gld_paccept(gld_t *gld, pktinfo_t *pktinfo)
{
        /*
         * Note that it is okay to examine gld_vlan because macinfo->gldm_lock
         * is held.
         *
         * If a stream is a ETHERTYPE_VLAN listener, it must
         * accept all tagged packets as those packets have SAP value
         * ETHERTYPE_VLAN.
         */
        return (gld->gld_flags & GLD_PROM_PHYS &&
            (MATCH(gld, pktinfo) || gld->gld_flags & GLD_PROM_SAP ||
            (GLD_IS_PHYS(gld) && gld->gld_sap == ETHERTYPE_VLAN &&
            pktinfo->isTagged)));

}

static void
gld_passon(gld_t *gld, mblk_t *mp, pktinfo_t *pktinfo,
    void (*send)(queue_t *qp, mblk_t *mp))
{
        boolean_t is_phys = GLD_IS_PHYS(gld);
        int skiplen;
        boolean_t addtag = B_FALSE;
        uint32_t vtag = 0;

#ifdef GLD_DEBUG
        if (gld_debug & GLDTRACE)
                cmn_err(CE_NOTE, "gld_passon(%p, %p, %p)", (void *)gld,
                    (void *)mp, (void *)pktinfo);

        if ((gld_debug & GLDRECV) && (!(gld_debug & GLDNOBR) ||
            (!pktinfo->isBroadcast && !pktinfo->isMulticast)))
                cmn_err(CE_NOTE, "gld_passon: q: %p mblk: %p minor: %d sap: %x",
                    (void *)gld->gld_qptr->q_next, (void *)mp, gld->gld_minor,
                    gld->gld_sap);
#endif
        /*
         * Figure out how much of the packet header to throw away.
         *
         * Normal DLPI (non RAW/FAST) streams also want the
         * DL_UNITDATA_IND M_PROTO message block prepended to the M_DATA.
         */
        if (gld->gld_flags & GLD_RAW) {
                /*
                 * The packet will be tagged in the following cases:
                 *   - if priority is not 0
                 *   - a tagged packet sent on a physical link
                 */
                if ((pktinfo->isTagged && is_phys) || (pktinfo->user_pri != 0))
                        addtag = B_TRUE;
                skiplen = 0;
        } else {
                /*
                 * The packet will be tagged if it meets all below conditions:
                 *   -  this is a physical stream
                 *   -  this packet is tagged packet
                 *   -  the stream is either a DL_PROMISC_SAP listener or a
                 *      ETHERTYPE_VLAN listener
                 */
                if (is_phys && pktinfo->isTagged &&
                    ((gld->gld_sap == ETHERTYPE_VLAN) ||
                    (gld->gld_flags & GLD_PROM_SAP))) {
                        addtag = B_TRUE;
                }

                skiplen = pktinfo->macLen;              /* skip mac header */
                if (gld->gld_ethertype)
                        skiplen += pktinfo->hdrLen;     /* skip any extra */
        }
        if (skiplen >= pktinfo->pktLen) {
                /*
                 * If the interpreter did its job right, then it cannot be
                 * asking us to skip more bytes than are in the packet!
                 * However, there could be zero data bytes left after the
                 * amount to skip.  DLPI specifies that passed M_DATA blocks
                 * should contain at least one byte of data, so if we have
                 * none we just drop it.
                 */
                ASSERT(!(skiplen > pktinfo->pktLen));
                freemsg(mp);
                return;
        }

        if (addtag) {
                mblk_t *savemp = mp;

                vtag = GLD_MAKE_VTAG(pktinfo->user_pri, pktinfo->cfi,
                    is_phys ? pktinfo->vid : VLAN_VID_NONE);
                if ((mp = gld_insert_vtag_ether(mp, vtag)) == NULL) {
                        freemsg(savemp);
                        return;
                }
        }

        /*
         * Skip over the header(s), taking care to possibly handle message
         * fragments shorter than the amount we need to skip.  Hopefully
         * the driver will put the entire packet, or at least the entire
         * header, into a single message block.  But we handle it if not.
         */
        while (skiplen >= MBLKL(mp)) {
                mblk_t *savemp = mp;
                skiplen -= MBLKL(mp);
                mp = mp->b_cont;
                ASSERT(mp != NULL);     /* because skiplen < pktinfo->pktLen */
                freeb(savemp);
        }
        mp->b_rptr += skiplen;

        /* Add M_PROTO if necessary, and pass upstream */
        if (((gld->gld_flags & GLD_FAST) && !pktinfo->isMulticast &&
            !pktinfo->isBroadcast) || (gld->gld_flags & GLD_RAW)) {
                /* RAW/FAST: just send up the M_DATA */
                (*send)(gld->gld_qptr, mp);
        } else {
                /* everybody else wants to see a unitdata_ind structure */
                mp = gld_addudind(gld, mp, pktinfo, addtag);
                if (mp)
                        (*send)(gld->gld_qptr, mp);
                /* if it failed, gld_addudind already bumped statistic */
        }
}

/*
 * gld_addudind(gld, mp, pktinfo)
 * format a DL_UNITDATA_IND message to be sent upstream to the user
 */
static mblk_t *
gld_addudind(gld_t *gld, mblk_t *mp, pktinfo_t *pktinfo, boolean_t tagged)
{
        gld_mac_info_t          *macinfo = gld->gld_mac_info;
        gld_vlan_t              *vlan = (gld_vlan_t *)gld->gld_vlan;
        dl_unitdata_ind_t       *dludindp;
        mblk_t                  *nmp;
        int                     size;
        int                     type;

#ifdef GLD_DEBUG
        if (gld_debug & GLDTRACE)
                cmn_err(CE_NOTE, "gld_addudind(%p, %p, %p)", (void *)gld,
                    (void *)mp, (void *)pktinfo);
#endif
        ASSERT(macinfo != NULL);

        /*
         * Allocate the DL_UNITDATA_IND M_PROTO header, if allocation fails
         * might as well discard since we can't go further
         */
        size = sizeof (dl_unitdata_ind_t) +
            2 * (macinfo->gldm_addrlen + abs(macinfo->gldm_saplen));
        if ((nmp = allocb(size, BPRI_MED)) == NULL) {
                freemsg(mp);
                BUMP(vlan->gldv_stats, NULL, glds_gldnorcvbuf, 1);
#ifdef GLD_DEBUG
                if (gld_debug & GLDERRS)
                        cmn_err(CE_WARN,
                            "gld_addudind: allocb failed");
#endif
                return (NULL);
        }
        DB_TYPE(nmp) = M_PROTO;
        nmp->b_rptr = nmp->b_datap->db_lim - size;

        if (tagged)
                type = ETHERTYPE_VLAN;
        else
                type = (gld->gld_ethertype) ? pktinfo->ethertype : 0;


        /*
         * now setup the DL_UNITDATA_IND header
         *
         * XXX This looks broken if the saps aren't two bytes.
         */
        dludindp = (dl_unitdata_ind_t *)nmp->b_rptr;
        dludindp->dl_primitive = DL_UNITDATA_IND;
        dludindp->dl_src_addr_length =
            dludindp->dl_dest_addr_length = macinfo->gldm_addrlen +
            abs(macinfo->gldm_saplen);
        dludindp->dl_dest_addr_offset = sizeof (dl_unitdata_ind_t);
        dludindp->dl_src_addr_offset = dludindp->dl_dest_addr_offset +
            dludindp->dl_dest_addr_length;

        dludindp->dl_group_address = (pktinfo->isMulticast ||
            pktinfo->isBroadcast);

        nmp->b_wptr = nmp->b_rptr + dludindp->dl_dest_addr_offset;

        mac_copy(pktinfo->dhost, nmp->b_wptr, macinfo->gldm_addrlen);
        nmp->b_wptr += macinfo->gldm_addrlen;

        ASSERT(macinfo->gldm_saplen == -2);     /* XXX following code assumes */
        *(ushort_t *)(nmp->b_wptr) = type;
        nmp->b_wptr += abs(macinfo->gldm_saplen);

        ASSERT(nmp->b_wptr == nmp->b_rptr + dludindp->dl_src_addr_offset);

        mac_copy(pktinfo->shost, nmp->b_wptr, macinfo->gldm_addrlen);
        nmp->b_wptr += macinfo->gldm_addrlen;

        *(ushort_t *)(nmp->b_wptr) = type;
        nmp->b_wptr += abs(macinfo->gldm_saplen);

        if (pktinfo->nosource)
                dludindp->dl_src_addr_offset = dludindp->dl_src_addr_length = 0;
        linkb(nmp, mp);
        return (nmp);
}

/* ======================================================= */
/* wsrv group: called from wsrv, single threaded per queue */
/* ======================================================= */

/*
 * We go to some trouble to avoid taking the same lock during normal
 * transmit processing as we do during normal receive processing.
 *
 * Elements of the per-instance macinfo and per-stream gld_t structures
 * are for the most part protected by the GLDM_LOCK rwlock/mutex.
 * (Elements of the gld_mac_pvt_t structure are considered part of the
 * macinfo structure for purposes of this discussion).
 *
 * However, it is more complicated than that:
 *
 *      Elements of the macinfo structure that are set before the macinfo
 *      structure is added to its device list by gld_register(), and never
 *      thereafter modified, are accessed without requiring taking the lock.
 *      A similar rule applies to those elements of the gld_t structure that
 *      are written by gld_open() before the stream is added to any list.
 *
 *      Most other elements of the macinfo structure may only be read or
 *      written while holding the maclock.
 *
 *      Most writable elements of the gld_t structure are written only
 *      within the single-threaded domain of wsrv() and subsidiaries.
 *      (This domain includes open/close while qprocs are not on.)
 *      The maclock need not be taken while within that domain
 *      simply to read those elements.  Writing to them, even within
 *      that domain, or reading from it outside that domain, requires
 *      holding the maclock.  Exception:  if the stream is not
 *      presently attached to a PPA, there is no associated macinfo,
 *      and no maclock need be taken.
 *
 *      The curr_macaddr element of the mac private structure is also
 *      protected by the GLDM_LOCK rwlock/mutex, like most other members
 *      of that structure. However, there are a few instances in the
 *      transmit path where we choose to forgo lock protection when
 *      reading this variable. This is to avoid lock contention between
 *      threads executing the DL_UNITDATA_REQ case and receive threads.
 *      In doing so we will take a small risk or a few corrupted packets
 *      during the short an rare times when someone is changing the interface's
 *      physical address. We consider the small cost in this rare case to be
 *      worth the benefit of reduced lock contention under normal operating
 *      conditions. The risk/cost is small because:
 *          1. there is no guarantee at this layer of uncorrupted delivery.
 *          2. the physaddr doesn't change very often - no performance hit.
 *          3. if the physaddr changes, other stuff is going to be screwed
 *             up for a while anyway, while other sites refigure ARP, etc.,
 *             so losing a couple of packets is the least of our worries.
 *
 *      The list of streams associated with a macinfo is protected by
 *      two locks:  the per-macinfo maclock, and the per-major-device
 *      gld_devlock.  Both must be held to modify the list, but either
 *      may be held to protect the list during reading/traversing.  This
 *      allows independent locking for multiple instances in the receive
 *      path (using macinfo), while facilitating routines that must search
 *      the entire set of streams associated with a major device, such as
 *      gld_findminor(), gld_finddevinfo(), close().  The "nstreams"
 *      macinfo element, and the gld_mac_info gld_t element, are similarly
 *      protected, since they change at exactly the same time macinfo
 *      streams list does.
 *
 *      The list of macinfo structures associated with a major device
 *      structure is protected by the gld_devlock, as is the per-major
 *      list of Style 2 streams in the DL_UNATTACHED state.
 *
 *      The list of major devices is kept on a module-global list
 *      gld_device_list, which has its own lock to protect the list.
 *
 *      When it is necessary to hold more than one lock at a time, they
 *      are acquired in this "outside in" order:
 *              gld_device_list.gld_devlock
 *              glddev->gld_devlock
 *              GLDM_LOCK(macinfo)
 *
 *      Finally, there are some "volatile" elements of the gld_t structure
 *      used for synchronization between various routines that don't share
 *      the same mutexes.  See the routines for details.  These are:
 *              gld_xwait       between gld_wsrv() and gld_sched()
 *              gld_sched_ran   between gld_wsrv() and gld_sched()
 *              gld_in_unbind   between gld_wput() and wsrv's gld_unbind()
 *              gld_wput_count  between gld_wput() and wsrv's gld_unbind()
 *              gld_in_wsrv     between gld_wput() and gld_wsrv()
 *                              (used in conjunction with q->q_first)
 */

/*
 * gld_ioctl (q, mp)
 * handles all ioctl requests passed downstream. This routine is
 * passed a pointer to the message block with the ioctl request in it, and a
 * pointer to the queue so it can respond to the ioctl request with an ack.
 */
int
gld_ioctl(queue_t *q, mblk_t *mp)
{
        struct iocblk *iocp;
        gld_t *gld;
        gld_mac_info_t *macinfo;

#ifdef GLD_DEBUG
        if (gld_debug & GLDTRACE)
                cmn_err(CE_NOTE, "gld_ioctl(%p %p)", (void *)q, (void *)mp);
#endif
        gld = (gld_t *)q->q_ptr;
        iocp = (struct iocblk *)mp->b_rptr;
        switch (iocp->ioc_cmd) {
        case DLIOCRAW:          /* raw M_DATA mode */
                gld->gld_flags |= GLD_RAW;
                DB_TYPE(mp) = M_IOCACK;
                qreply(q, mp);
                break;

        case DL_IOC_HDR_INFO:   /* fastpath */
                /*
                 * DL_IOC_HDR_INFO should only come from IP. The one
                 * initiated from user-land should not be allowed.
                 */
                if ((gld_global_options & GLD_OPT_NO_FASTPATH) ||
                    (iocp->ioc_cr != kcred)) {
                        miocnak(q, mp, 0, EINVAL);
                        break;
                }
                gld_fastpath(gld, q, mp);
                break;

        case DLIOCMARGININFO: { /* margin size */
                int err;

                if ((macinfo = gld->gld_mac_info) == NULL) {
                        miocnak(q, mp, 0, EINVAL);
                        break;
                }

                if ((err = miocpullup(mp, sizeof (uint32_t))) != 0) {
                        miocnak(q, mp, 0, err);
                        break;
                }

                *((uint32_t *)mp->b_cont->b_rptr) = macinfo->gldm_margin;
                miocack(q, mp, sizeof (uint32_t), 0);
                break;
        }
        default:
                macinfo  = gld->gld_mac_info;
                if (macinfo == NULL || macinfo->gldm_ioctl == NULL) {
                        miocnak(q, mp, 0, EINVAL);
                        break;
                }

                GLDM_LOCK(macinfo, RW_WRITER);
                (void) (*macinfo->gldm_ioctl) (macinfo, q, mp);
                GLDM_UNLOCK(macinfo);
                break;
        }
        return (0);
}

/*
 * Since the rules for "fastpath" mode don't seem to be documented
 * anywhere, I will describe GLD's rules for fastpath users here:
 *
 * Once in this mode you remain there until close.
 * If you unbind/rebind you should get a new header using DL_IOC_HDR_INFO.
 * You must be bound (DL_IDLE) to transmit.
 * There are other rules not listed above.
 */
static void
gld_fastpath(gld_t *gld, queue_t *q, mblk_t *mp)
{
        gld_interface_t *ifp;
        gld_mac_info_t *macinfo;
        dl_unitdata_req_t *dludp;
        mblk_t *nmp;
        t_scalar_t off, len;
        uint_t maclen;
        int error;

        if (gld->gld_state != DL_IDLE) {
                miocnak(q, mp, 0, EINVAL);
                return;
        }

        macinfo = gld->gld_mac_info;
        ASSERT(macinfo != NULL);
        maclen = macinfo->gldm_addrlen + abs(macinfo->gldm_saplen);

        error = miocpullup(mp, sizeof (dl_unitdata_req_t) + maclen);
        if (error != 0) {
                miocnak(q, mp, 0, error);
                return;
        }

        dludp = (dl_unitdata_req_t *)mp->b_cont->b_rptr;
        off = dludp->dl_dest_addr_offset;
        len = dludp->dl_dest_addr_length;
        if (dludp->dl_primitive != DL_UNITDATA_REQ ||
            !MBLKIN(mp->b_cont, off, len) || len != maclen) {
                miocnak(q, mp, 0, EINVAL);
                return;
        }

        /*
         * We take the fastpath request as a declaration that they will accept
         * M_DATA messages from us, whether or not we are willing to accept
         * M_DATA from them.  This allows us to have fastpath in one direction
         * (flow upstream) even on media with Source Routing, where we are
         * unable to provide a fixed MAC header to be prepended to downstream
         * flowing packets.  So we set GLD_FAST whether or not we decide to
         * allow them to send M_DATA down to us.
         */
        GLDM_LOCK(macinfo, RW_WRITER);
        gld->gld_flags |= GLD_FAST;
        GLDM_UNLOCK(macinfo);

        ifp = ((gld_mac_pvt_t *)macinfo->gldm_mac_pvt)->interfacep;

        /* This will fail for Source Routing media */
        /* Also on Ethernet on 802.2 SAPs */
        if ((nmp = (*ifp->mkfastpath)(gld, mp)) == NULL) {
                miocnak(q, mp, 0, ENOMEM);
                return;
        }

        /*
         * Link new mblk in after the "request" mblks.
         */
        linkb(mp, nmp);
        miocack(q, mp, msgdsize(mp->b_cont), 0);
}

/*
 * gld_cmds (q, mp)
 *      process the DL commands as defined in dlpi.h
 *      note that the primitives return status which is passed back
 *      to the service procedure.  If the value is GLDE_RETRY, then
 *      it is assumed that processing must stop and the primitive has
 *      been put back onto the queue.  If the value is any other error,
 *      then an error ack is generated by the service procedure.
 */
static int
gld_cmds(queue_t *q, mblk_t *mp)
{
        union DL_primitives *dlp = (union DL_primitives *)mp->b_rptr;
        gld_t *gld = (gld_t *)(q->q_ptr);
        int result = DL_BADPRIM;
        int mblkl = MBLKL(mp);
        t_uscalar_t dlreq;

        /* Make sure we have at least dlp->dl_primitive */
        if (mblkl < sizeof (dlp->dl_primitive))
                return (DL_BADPRIM);

        dlreq = dlp->dl_primitive;
#ifdef  GLD_DEBUG
        if (gld_debug & GLDTRACE)
                cmn_err(CE_NOTE,
                    "gld_cmds(%p, %p):dlp=%p, dlp->dl_primitive=%d",
                    (void *)q, (void *)mp, (void *)dlp, dlreq);
#endif

        switch (dlreq) {
        case DL_UDQOS_REQ:
                if (mblkl < DL_UDQOS_REQ_SIZE)
                        break;
                result = gld_udqos(q, mp);
                break;

        case DL_BIND_REQ:
                if (mblkl < DL_BIND_REQ_SIZE)
                        break;
                result = gld_bind(q, mp);
                break;

        case DL_UNBIND_REQ:
                if (mblkl < DL_UNBIND_REQ_SIZE)
                        break;
                result = gld_unbind(q, mp);
                break;

        case DL_UNITDATA_REQ:
                if (mblkl < DL_UNITDATA_REQ_SIZE)
                        break;
                result = gld_unitdata(q, mp);
                break;

        case DL_INFO_REQ:
                if (mblkl < DL_INFO_REQ_SIZE)
                        break;
                result = gld_inforeq(q, mp);
                break;

        case DL_ATTACH_REQ:
                if (mblkl < DL_ATTACH_REQ_SIZE)
                        break;
                if (gld->gld_style == DL_STYLE2)
                        result = gldattach(q, mp);
                else
                        result = DL_NOTSUPPORTED;
                break;

        case DL_DETACH_REQ:
                if (mblkl < DL_DETACH_REQ_SIZE)
                        break;
                if (gld->gld_style == DL_STYLE2)
                        result = gldunattach(q, mp);
                else
                        result = DL_NOTSUPPORTED;
                break;

        case DL_ENABMULTI_REQ:
                if (mblkl < DL_ENABMULTI_REQ_SIZE)
                        break;
                result = gld_enable_multi(q, mp);
                break;

        case DL_DISABMULTI_REQ:
                if (mblkl < DL_DISABMULTI_REQ_SIZE)
                        break;
                result = gld_disable_multi(q, mp);
                break;

        case DL_PHYS_ADDR_REQ:
                if (mblkl < DL_PHYS_ADDR_REQ_SIZE)
                        break;
                result = gld_physaddr(q, mp);
                break;

        case DL_SET_PHYS_ADDR_REQ:
                if (mblkl < DL_SET_PHYS_ADDR_REQ_SIZE)
                        break;
                result = gld_setaddr(q, mp);
                break;

        case DL_PROMISCON_REQ:
                if (mblkl < DL_PROMISCON_REQ_SIZE)
                        break;
                result = gld_promisc(q, mp, dlreq, B_TRUE);
                break;

        case DL_PROMISCOFF_REQ:
                if (mblkl < DL_PROMISCOFF_REQ_SIZE)
                        break;
                result = gld_promisc(q, mp, dlreq, B_FALSE);
                break;

        case DL_GET_STATISTICS_REQ:
                if (mblkl < DL_GET_STATISTICS_REQ_SIZE)
                        break;
                result = gld_get_statistics(q, mp);
                break;

        case DL_CAPABILITY_REQ:
                if (mblkl < DL_CAPABILITY_REQ_SIZE)
                        break;
                result = gld_cap(q, mp);
                break;

        case DL_NOTIFY_REQ:
                if (mblkl < DL_NOTIFY_REQ_SIZE)
                        break;
                result = gld_notify_req(q, mp);
                break;

        case DL_XID_REQ:
        case DL_XID_RES:
        case DL_TEST_REQ:
        case DL_TEST_RES:
        case DL_CONTROL_REQ:
        case DL_PASSIVE_REQ:
                result = DL_NOTSUPPORTED;
                break;

        default:
#ifdef  GLD_DEBUG
                if (gld_debug & GLDERRS)
                        cmn_err(CE_WARN,
                            "gld_cmds: unknown M_PROTO message: %d",
                            dlreq);
#endif
                result = DL_BADPRIM;
        }

        return (result);
}

static int
gld_cap(queue_t *q, mblk_t *mp)
{
        gld_t *gld = (gld_t *)q->q_ptr;
        dl_capability_req_t *dlp = (dl_capability_req_t *)mp->b_rptr;

        if (gld->gld_state == DL_UNATTACHED)
                return (DL_OUTSTATE);

        if (dlp->dl_sub_length == 0)
                return (gld_cap_ack(q, mp));

        return (gld_cap_enable(q, mp));
}

static int
gld_cap_ack(queue_t *q, mblk_t *mp)
{
        gld_t *gld = (gld_t *)q->q_ptr;
        gld_mac_info_t *macinfo = gld->gld_mac_info;
        gld_interface_t *ifp;
        dl_capability_ack_t *dlap;
        dl_capability_sub_t *dlsp;
        size_t size = sizeof (dl_capability_ack_t);
        size_t subsize = 0;

        ifp = ((gld_mac_pvt_t *)macinfo->gldm_mac_pvt)->interfacep;

        if (macinfo->gldm_capabilities & GLD_CAP_CKSUM_ANY)
                subsize += sizeof (dl_capability_sub_t) +
                    sizeof (dl_capab_hcksum_t);
        if (macinfo->gldm_capabilities & GLD_CAP_ZEROCOPY)
                subsize += sizeof (dl_capability_sub_t) +
                    sizeof (dl_capab_zerocopy_t);
        if (macinfo->gldm_options & GLDOPT_MDT)
                subsize += (sizeof (dl_capability_sub_t) +
                    sizeof (dl_capab_mdt_t));

        if ((mp = mexchange(q, mp, size + subsize, M_PROTO,
            DL_CAPABILITY_ACK)) == NULL)
                return (GLDE_OK);

        dlap = (dl_capability_ack_t *)mp->b_rptr;
        dlap->dl_sub_offset = 0;
        if ((dlap->dl_sub_length = subsize) != 0)
                dlap->dl_sub_offset = sizeof (dl_capability_ack_t);
        dlsp = (dl_capability_sub_t *)&dlap[1];

        if (macinfo->gldm_capabilities & GLD_CAP_CKSUM_ANY) {
                dl_capab_hcksum_t *dlhp = (dl_capab_hcksum_t *)&dlsp[1];

                dlsp->dl_cap = DL_CAPAB_HCKSUM;
                dlsp->dl_length = sizeof (dl_capab_hcksum_t);

                dlhp->hcksum_version = HCKSUM_VERSION_1;

                dlhp->hcksum_txflags = 0;
                if (macinfo->gldm_capabilities & GLD_CAP_CKSUM_PARTIAL)
                        dlhp->hcksum_txflags |= HCKSUM_INET_PARTIAL;
                if (macinfo->gldm_capabilities & GLD_CAP_CKSUM_FULL_V4)
                        dlhp->hcksum_txflags |= HCKSUM_INET_FULL_V4;
                if (macinfo->gldm_capabilities & GLD_CAP_CKSUM_FULL_V6)
                        dlhp->hcksum_txflags |= HCKSUM_INET_FULL_V6;
                if (macinfo->gldm_capabilities & GLD_CAP_CKSUM_IPHDR)
                        dlhp->hcksum_txflags |= HCKSUM_IPHDRCKSUM;

                dlcapabsetqid(&(dlhp->hcksum_mid), RD(q));
                dlsp = (dl_capability_sub_t *)&dlhp[1];
        }

        if (macinfo->gldm_capabilities & GLD_CAP_ZEROCOPY) {
                dl_capab_zerocopy_t *dlzp = (dl_capab_zerocopy_t *)&dlsp[1];

                dlsp->dl_cap = DL_CAPAB_ZEROCOPY;
                dlsp->dl_length = sizeof (dl_capab_zerocopy_t);
                dlzp->zerocopy_version = ZEROCOPY_VERSION_1;
                dlzp->zerocopy_flags = DL_CAPAB_VMSAFE_MEM;

                dlcapabsetqid(&(dlzp->zerocopy_mid), RD(q));
                dlsp = (dl_capability_sub_t *)&dlzp[1];
        }

        if (macinfo->gldm_options & GLDOPT_MDT) {
                dl_capab_mdt_t *dlmp = (dl_capab_mdt_t *)&dlsp[1];

                dlsp->dl_cap = DL_CAPAB_MDT;
                dlsp->dl_length = sizeof (dl_capab_mdt_t);

                dlmp->mdt_version = MDT_VERSION_2;
                dlmp->mdt_max_pld = macinfo->gldm_mdt_segs;
                dlmp->mdt_span_limit = macinfo->gldm_mdt_sgl;
                dlcapabsetqid(&dlmp->mdt_mid, OTHERQ(q));
                dlmp->mdt_flags = DL_CAPAB_MDT_ENABLE;
                dlmp->mdt_hdr_head = ifp->hdr_size;
                dlmp->mdt_hdr_tail = 0;
        }

        qreply(q, mp);
        return (GLDE_OK);
}

static int
gld_cap_enable(queue_t *q, mblk_t *mp)
{
        dl_capability_req_t *dlp;
        dl_capability_sub_t *dlsp;
        dl_capab_hcksum_t *dlhp;
        offset_t off;
        size_t len;
        size_t size;
        offset_t end;

        dlp = (dl_capability_req_t *)mp->b_rptr;
        dlp->dl_primitive = DL_CAPABILITY_ACK;

        off = dlp->dl_sub_offset;
        len = dlp->dl_sub_length;

        if (!MBLKIN(mp, off, len))
                return (DL_BADPRIM);

        end = off + len;
        while (off < end) {
                dlsp = (dl_capability_sub_t *)(mp->b_rptr + off);
                size = sizeof (dl_capability_sub_t) + dlsp->dl_length;
                if (off + size > end)
                        return (DL_BADPRIM);

                switch (dlsp->dl_cap) {
                case DL_CAPAB_HCKSUM:
                        dlhp = (dl_capab_hcksum_t *)&dlsp[1];
                        /* nothing useful we can do with the contents */
                        dlcapabsetqid(&(dlhp->hcksum_mid), RD(q));
                        break;
                default:
                        break;
                }

                off += size;
        }

        qreply(q, mp);
        return (GLDE_OK);
}

/*
 * Send a copy of the DL_NOTIFY_IND message <mp> to each stream that has
 * requested the specific <notification> that the message carries AND is
 * eligible and ready to receive the notification immediately.
 *
 * This routine ignores flow control. Notifications will be sent regardless.
 *
 * In all cases, the original message passed in is freed at the end of
 * the routine.
 */
static void
gld_notify_qs(gld_mac_info_t *macinfo, mblk_t *mp, uint32_t notification)
{
        gld_mac_pvt_t *mac_pvt;
        gld_vlan_t *vlan;
        gld_t *gld;
        mblk_t *nmp;
        int i;

        ASSERT(GLDM_LOCK_HELD_WRITE(macinfo));

        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;

        /*
         * Search all the streams attached to this macinfo looking
         * for those eligible to receive the present notification.
         */
        for (i = 0; i < VLAN_HASHSZ; i++) {
                for (vlan = mac_pvt->vlan_hash[i];
                    vlan != NULL; vlan = vlan->gldv_next) {
                        for (gld = vlan->gldv_str_next;
                            gld != (gld_t *)&vlan->gldv_str_next;
                            gld = gld->gld_next) {
                                ASSERT(gld->gld_qptr != NULL);
                                ASSERT(gld->gld_state == DL_IDLE ||
                                    gld->gld_state == DL_UNBOUND);
                                ASSERT(gld->gld_mac_info == macinfo);

                                if (gld->gld_flags & GLD_STR_CLOSING)
                                        continue; /* not eligible - skip */
                                if (!(notification & gld->gld_notifications))
                                        continue; /* not wanted - skip */
                                if ((nmp = dupmsg(mp)) == NULL)
                                        continue; /* can't copy - skip */

                                /*
                                 * All OK; send dup'd notification up this
                                 * stream
                                 */
                                qreply(WR(gld->gld_qptr), nmp);
                        }
                }
        }

        /*
         * Drop the original message block now
         */
        freemsg(mp);
}

/*
 * For each (understood) bit in the <notifications> argument, contruct
 * a DL_NOTIFY_IND message and send it to the specified <q>, or to all
 * eligible queues if <q> is NULL.
 */
static void
gld_notify_ind(gld_mac_info_t *macinfo, uint32_t notifications, queue_t *q)
{
        gld_mac_pvt_t *mac_pvt;
        dl_notify_ind_t *dlnip;
        struct gld_stats *stats;
        mblk_t *mp;
        size_t size;
        uint32_t bit;

        GLDM_LOCK(macinfo, RW_WRITER);

        /*
         * The following cases shouldn't happen, but just in case the
         * MAC driver calls gld_linkstate() at an inappropriate time, we
         * check anyway ...
         */
        if (!(macinfo->gldm_GLD_flags & GLD_MAC_READY)) {
                GLDM_UNLOCK(macinfo);
                return;                         /* not ready yet        */
        }

        if (macinfo->gldm_GLD_flags & GLD_UNREGISTERED) {
                GLDM_UNLOCK(macinfo);
                return;                         /* not ready anymore    */
        }

        /*
         * Make sure the kstats are up to date, 'cos we use some of
         * the kstat values below, specifically the link speed ...
         */
        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        stats = mac_pvt->statistics;
        if (macinfo->gldm_get_stats)
                (void) (*macinfo->gldm_get_stats)(macinfo, stats);

        for (bit = 1; notifications != 0; bit <<= 1) {
                if ((notifications & bit) == 0)
                        continue;
                notifications &= ~bit;

                size = DL_NOTIFY_IND_SIZE;
                if (bit == DL_NOTE_PHYS_ADDR)
                        size += macinfo->gldm_addrlen;
                if ((mp = allocb(size, BPRI_MED)) == NULL)
                        continue;

                mp->b_datap->db_type = M_PROTO;
                mp->b_wptr = mp->b_rptr + size;
                dlnip = (dl_notify_ind_t *)mp->b_rptr;
                dlnip->dl_primitive = DL_NOTIFY_IND;
                dlnip->dl_notification = 0;
                dlnip->dl_data = 0;
                dlnip->dl_addr_length = 0;
                dlnip->dl_addr_offset = 0;

                switch (bit) {
                case DL_NOTE_PROMISC_ON_PHYS:
                case DL_NOTE_PROMISC_OFF_PHYS:
                        if (mac_pvt->nprom != 0)
                                dlnip->dl_notification = bit;
                        break;

                case DL_NOTE_LINK_DOWN:
                        if (macinfo->gldm_linkstate == GLD_LINKSTATE_DOWN)
                                dlnip->dl_notification = bit;
                        break;

                case DL_NOTE_LINK_UP:
                        if (macinfo->gldm_linkstate == GLD_LINKSTATE_UP)
                                dlnip->dl_notification = bit;
                        break;

                case DL_NOTE_SPEED:
                        /*
                         * Conversion required here:
                         *      GLD keeps the speed in bit/s in a uint64
                         *      DLPI wants it in kb/s in a uint32
                         * Fortunately this is still big enough for 10Gb/s!
                         */
                        dlnip->dl_notification = bit;
                        dlnip->dl_data = stats->glds_speed/1000ULL;
                        break;

                case DL_NOTE_PHYS_ADDR:
                        dlnip->dl_notification = bit;
                        dlnip->dl_data = DL_CURR_PHYS_ADDR;
                        dlnip->dl_addr_offset = sizeof (dl_notify_ind_t);
                        dlnip->dl_addr_length = macinfo->gldm_addrlen +
                            abs(macinfo->gldm_saplen);
                        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
                        mac_copy(mac_pvt->curr_macaddr,
                            mp->b_rptr + sizeof (dl_notify_ind_t),
                            macinfo->gldm_addrlen);
                        break;

                default:
                        break;
                }

                if (dlnip->dl_notification == 0)
                        freemsg(mp);
                else if (q != NULL)
                        qreply(q, mp);
                else
                        gld_notify_qs(macinfo, mp, bit);
        }

        GLDM_UNLOCK(macinfo);
}

/*
 * gld_notify_req - handle a DL_NOTIFY_REQ message
 */
static int
gld_notify_req(queue_t *q, mblk_t *mp)
{
        gld_t *gld = (gld_t *)q->q_ptr;
        gld_mac_info_t *macinfo;
        gld_mac_pvt_t *pvt;
        dl_notify_req_t *dlnrp;
        dl_notify_ack_t *dlnap;

        ASSERT(gld != NULL);
        ASSERT(gld->gld_qptr == RD(q));

        dlnrp = (dl_notify_req_t *)mp->b_rptr;

#ifdef GLD_DEBUG
        if (gld_debug & GLDTRACE)
                cmn_err(CE_NOTE, "gld_notify_req(%p %p)",
                    (void *)q, (void *)mp);
#endif

        if (gld->gld_state == DL_UNATTACHED) {
#ifdef GLD_DEBUG
                if (gld_debug & GLDERRS)
                        cmn_err(CE_NOTE, "gld_notify_req: wrong state (%d)",
                            gld->gld_state);
#endif
                return (DL_OUTSTATE);
        }

        /*
         * Remember what notifications are required by this stream
         */
        macinfo = gld->gld_mac_info;
        pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;

        gld->gld_notifications = dlnrp->dl_notifications & pvt->notifications;

        /*
         * The return DL_NOTIFY_ACK carries the bitset of notifications
         * that this driver can provide, independently of which ones have
         * previously been or are now being requested.
         */
        if ((mp = mexchange(q, mp, sizeof (dl_notify_ack_t), M_PCPROTO,
            DL_NOTIFY_ACK)) == NULL)
                return (DL_SYSERR);

        dlnap = (dl_notify_ack_t *)mp->b_rptr;
        dlnap->dl_notifications = pvt->notifications;
        qreply(q, mp);

        /*
         * A side effect of a DL_NOTIFY_REQ is that after the DL_NOTIFY_ACK
         * reply, the the requestor gets zero or more DL_NOTIFY_IND messages
         * that provide the current status.
         */
        gld_notify_ind(macinfo, gld->gld_notifications, q);

        return (GLDE_OK);
}

/*
 * gld_linkstate()
 *      Called by driver to tell GLD the state of the physical link.
 *      As a side effect, sends a DL_NOTE_LINK_UP or DL_NOTE_LINK_DOWN
 *      notification to each client that has previously requested such
 *      notifications
 */
void
gld_linkstate(gld_mac_info_t *macinfo, int32_t newstate)
{
        uint32_t notification;

        switch (newstate) {
        default:
                return;

        case GLD_LINKSTATE_DOWN:
                notification = DL_NOTE_LINK_DOWN;
                break;

        case GLD_LINKSTATE_UP:
                notification = DL_NOTE_LINK_UP | DL_NOTE_SPEED;
                break;

        case GLD_LINKSTATE_UNKNOWN:
                notification = 0;
                break;
        }

        GLDM_LOCK(macinfo, RW_WRITER);
        if (macinfo->gldm_linkstate == newstate)
                notification = 0;
        else
                macinfo->gldm_linkstate = newstate;
        GLDM_UNLOCK(macinfo);

        if (notification)
                gld_notify_ind(macinfo, notification, NULL);
}

/*
 * gld_udqos - set the current QoS parameters (priority only at the moment).
 */
static int
gld_udqos(queue_t *q, mblk_t *mp)
{
        dl_udqos_req_t *dlp;
        gld_t  *gld = (gld_t *)q->q_ptr;
        int off;
        int len;
        dl_qos_cl_sel1_t *selp;

        ASSERT(gld);
        ASSERT(gld->gld_qptr == RD(q));

#ifdef GLD_DEBUG
        if (gld_debug & GLDTRACE)
                cmn_err(CE_NOTE, "gld_udqos(%p %p)", (void *)q, (void *)mp);
#endif

        if (gld->gld_state != DL_IDLE) {
#ifdef GLD_DEBUG
                if (gld_debug & GLDERRS)
                        cmn_err(CE_NOTE, "gld_udqos: wrong state (%d)",
                            gld->gld_state);
#endif
                return (DL_OUTSTATE);
        }

        dlp = (dl_udqos_req_t *)mp->b_rptr;
        off = dlp->dl_qos_offset;
        len = dlp->dl_qos_length;

        if (len != sizeof (dl_qos_cl_sel1_t) || !MBLKIN(mp, off, len))
                return (DL_BADQOSTYPE);

        selp = (dl_qos_cl_sel1_t *)(mp->b_rptr + off);
        if (selp->dl_qos_type != DL_QOS_CL_SEL1)
                return (DL_BADQOSTYPE);

        if (selp->dl_trans_delay != 0 &&
            selp->dl_trans_delay != DL_QOS_DONT_CARE)
                return (DL_BADQOSPARAM);
        if (selp->dl_protection != 0 &&
            selp->dl_protection != DL_QOS_DONT_CARE)
                return (DL_BADQOSPARAM);
        if (selp->dl_residual_error != 0 &&
            selp->dl_residual_error != DL_QOS_DONT_CARE)
                return (DL_BADQOSPARAM);
        if (selp->dl_priority < 0 || selp->dl_priority > 7)
                return (DL_BADQOSPARAM);

        gld->gld_upri = selp->dl_priority;

        dlokack(q, mp, DL_UDQOS_REQ);
        return (GLDE_OK);
}

static mblk_t *
gld_bindack(queue_t *q, mblk_t *mp)
{
        gld_t *gld = (gld_t *)q->q_ptr;
        gld_mac_info_t *macinfo = gld->gld_mac_info;
        gld_mac_pvt_t *mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        dl_bind_ack_t *dlp;
        size_t size;
        t_uscalar_t addrlen;
        uchar_t *sapp;

        addrlen = macinfo->gldm_addrlen + abs(macinfo->gldm_saplen);
        size = sizeof (dl_bind_ack_t) + addrlen;
        if ((mp = mexchange(q, mp, size, M_PCPROTO, DL_BIND_ACK)) == NULL)
                return (NULL);

        dlp = (dl_bind_ack_t *)mp->b_rptr;
        dlp->dl_sap = gld->gld_sap;
        dlp->dl_addr_length = addrlen;
        dlp->dl_addr_offset = sizeof (dl_bind_ack_t);
        dlp->dl_max_conind = 0;
        dlp->dl_xidtest_flg = 0;

        mac_copy(mac_pvt->curr_macaddr, (uchar_t *)&dlp[1],
            macinfo->gldm_addrlen);
        sapp = mp->b_rptr + dlp->dl_addr_offset + macinfo->gldm_addrlen;
        *(ushort_t *)sapp = gld->gld_sap;

        return (mp);
}

/*
 * gld_bind - determine if a SAP is already allocated and whether it is legal
 * to do the bind at this time
 */
static int
gld_bind(queue_t *q, mblk_t *mp)
{
        ulong_t sap;
        dl_bind_req_t *dlp;
        gld_t *gld = (gld_t *)q->q_ptr;
        gld_mac_info_t *macinfo = gld->gld_mac_info;

        ASSERT(gld);
        ASSERT(gld->gld_qptr == RD(q));

#ifdef GLD_DEBUG
        if (gld_debug & GLDTRACE)
                cmn_err(CE_NOTE, "gld_bind(%p %p)", (void *)q, (void *)mp);
#endif

        dlp = (dl_bind_req_t *)mp->b_rptr;
        sap = dlp->dl_sap;

#ifdef GLD_DEBUG
        if (gld_debug & GLDPROT)
                cmn_err(CE_NOTE, "gld_bind: lsap=%lx", sap);
#endif

        if (gld->gld_state != DL_UNBOUND) {
#ifdef GLD_DEBUG
                if (gld_debug & GLDERRS)
                        cmn_err(CE_NOTE, "gld_bind: bound or not attached (%d)",
                            gld->gld_state);
#endif
                return (DL_OUTSTATE);
        }
        ASSERT(macinfo);

        if (dlp->dl_service_mode != DL_CLDLS) {
                return (DL_UNSUPPORTED);
        }
        if (dlp->dl_xidtest_flg & (DL_AUTO_XID | DL_AUTO_TEST)) {
                return (DL_NOAUTO);
        }

        /*
         * Check sap validity and decide whether this stream accepts
         * IEEE 802.2 (LLC) packets.
         */
        if (sap > ETHERTYPE_MAX)
                return (DL_BADSAP);

        /*
         * Decide whether the SAP value selects EtherType encoding/decoding.
         * For compatibility with monolithic ethernet drivers, the range of
         * SAP values is different for DL_ETHER media.
         */
        switch (macinfo->gldm_type) {
        case DL_ETHER:
                gld->gld_ethertype = (sap > ETHERMTU);
                break;
        default:
                gld->gld_ethertype = (sap > GLD_MAX_802_SAP);
                break;
        }

        /* if we get to here, then the SAP is legal enough */
        GLDM_LOCK(macinfo, RW_WRITER);
        gld->gld_state = DL_IDLE;       /* bound and ready */
        gld->gld_sap = sap;
        if ((macinfo->gldm_type == DL_ETHER) && (sap == ETHERTYPE_VLAN))
                ((gld_vlan_t *)gld->gld_vlan)->gldv_nvlan_sap++;
        gld_set_ipq(gld);

#ifdef GLD_DEBUG
        if (gld_debug & GLDPROT)
                cmn_err(CE_NOTE, "gld_bind: ok - sap = %d", gld->gld_sap);
#endif

        /* ACK the BIND */
        mp = gld_bindack(q, mp);
        GLDM_UNLOCK(macinfo);

        if (mp != NULL) {
                qreply(q, mp);
                return (GLDE_OK);
        }

        return (DL_SYSERR);
}

/*
 * gld_unbind - perform an unbind of an LSAP or ether type on the stream.
 * The stream is still open and can be re-bound.
 */
static int
gld_unbind(queue_t *q, mblk_t *mp)
{
        gld_t *gld = (gld_t *)q->q_ptr;
        gld_mac_info_t *macinfo = gld->gld_mac_info;

        ASSERT(gld);

#ifdef GLD_DEBUG
        if (gld_debug & GLDTRACE)
                cmn_err(CE_NOTE, "gld_unbind(%p %p)", (void *)q, (void *)mp);
#endif

        if (gld->gld_state != DL_IDLE) {
#ifdef GLD_DEBUG
                if (gld_debug & GLDERRS)
                        cmn_err(CE_NOTE, "gld_unbind: wrong state (%d)",
                            gld->gld_state);
#endif
                return (DL_OUTSTATE);
        }
        ASSERT(macinfo);

        /*
         * Avoid unbinding (DL_UNBIND_REQ) while FAST/RAW is inside wput.
         * See comments above gld_start().
         */
        gld->gld_in_unbind = B_TRUE;    /* disallow wput=>start */
        membar_enter();
        if (gld->gld_wput_count != 0) {
                gld->gld_in_unbind = B_FALSE;
                ASSERT(mp);             /* we didn't come from close */
#ifdef GLD_DEBUG
                if (gld_debug & GLDETRACE)
                        cmn_err(CE_NOTE, "gld_unbind: defer for wput");
#endif
                (void) putbq(q, mp);
                qenable(q);             /* try again soon */
                return (GLDE_RETRY);
        }

        GLDM_LOCK(macinfo, RW_WRITER);
        if ((macinfo->gldm_type == DL_ETHER) &&
            (gld->gld_sap == ETHERTYPE_VLAN)) {
                ((gld_vlan_t *)gld->gld_vlan)->gldv_nvlan_sap--;
        }
        gld->gld_state = DL_UNBOUND;
        gld->gld_sap = 0;
        gld_set_ipq(gld);
        GLDM_UNLOCK(macinfo);

        membar_exit();
        gld->gld_in_unbind = B_FALSE;

        /* mp is NULL if we came from close */
        if (mp) {
                gld_flushqueue(q);      /* flush the queues */
                dlokack(q, mp, DL_UNBIND_REQ);
        }
        return (GLDE_OK);
}

/*
 * gld_inforeq - generate the response to an info request
 */
static int
gld_inforeq(queue_t *q, mblk_t *mp)
{
        gld_t           *gld;
        dl_info_ack_t   *dlp;
        int             bufsize;
        glddev_t        *glddev;
        gld_mac_info_t  *macinfo;
        gld_mac_pvt_t   *mac_pvt;
        int             sel_offset = 0;
        int             range_offset = 0;
        int             addr_offset;
        int             addr_length;
        int             sap_length;
        int             brdcst_offset;
        int             brdcst_length;
        uchar_t         *sapp;

#ifdef GLD_DEBUG
        if (gld_debug & GLDTRACE)
                cmn_err(CE_NOTE, "gld_inforeq(%p %p)", (void *)q, (void *)mp);
#endif
        gld = (gld_t *)q->q_ptr;
        ASSERT(gld);
        glddev = gld->gld_device;
        ASSERT(glddev);

        if (gld->gld_state == DL_IDLE || gld->gld_state == DL_UNBOUND) {
                macinfo = gld->gld_mac_info;
                ASSERT(macinfo != NULL);

                mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;

                addr_length = macinfo->gldm_addrlen;
                sap_length = macinfo->gldm_saplen;
                brdcst_length = macinfo->gldm_addrlen;
        } else {
                addr_length = glddev->gld_addrlen;
                sap_length = glddev->gld_saplen;
                brdcst_length = glddev->gld_addrlen;
        }

        bufsize = sizeof (dl_info_ack_t);

        addr_offset = bufsize;
        bufsize += addr_length;
        bufsize += abs(sap_length);

        brdcst_offset = bufsize;
        bufsize += brdcst_length;

        if (((gld_vlan_t *)gld->gld_vlan) != NULL) {
                sel_offset = P2ROUNDUP(bufsize, sizeof (int64_t));
                bufsize = sel_offset + sizeof (dl_qos_cl_sel1_t);

                range_offset = P2ROUNDUP(bufsize, sizeof (int64_t));
                bufsize = range_offset + sizeof (dl_qos_cl_range1_t);
        }

        if ((mp = mexchange(q, mp, bufsize, M_PCPROTO, DL_INFO_ACK)) == NULL)
                return (GLDE_OK);       /* nothing more to be done */

        bzero(mp->b_rptr, bufsize);

        dlp = (dl_info_ack_t *)mp->b_rptr;
        dlp->dl_primitive = DL_INFO_ACK;
        dlp->dl_version = DL_VERSION_2;
        dlp->dl_service_mode = DL_CLDLS;
        dlp->dl_current_state = gld->gld_state;
        dlp->dl_provider_style = gld->gld_style;

        if (sel_offset != 0) {
                dl_qos_cl_sel1_t        *selp;
                dl_qos_cl_range1_t      *rangep;

                ASSERT(range_offset != 0);

                dlp->dl_qos_offset = sel_offset;
                dlp->dl_qos_length = sizeof (dl_qos_cl_sel1_t);
                dlp->dl_qos_range_offset = range_offset;
                dlp->dl_qos_range_length = sizeof (dl_qos_cl_range1_t);

                selp = (dl_qos_cl_sel1_t *)(mp->b_rptr + sel_offset);
                selp->dl_qos_type = DL_QOS_CL_SEL1;
                selp->dl_priority = gld->gld_upri;

                rangep = (dl_qos_cl_range1_t *)(mp->b_rptr + range_offset);
                rangep->dl_qos_type = DL_QOS_CL_RANGE1;
                rangep->dl_priority.dl_min = 0;
                rangep->dl_priority.dl_max = 7;
        }

        if (gld->gld_state == DL_IDLE || gld->gld_state == DL_UNBOUND) {
                dlp->dl_min_sdu = macinfo->gldm_minpkt;
                dlp->dl_max_sdu = macinfo->gldm_maxpkt;
                dlp->dl_mac_type = macinfo->gldm_type;
                dlp->dl_addr_length = addr_length + abs(sap_length);
                dlp->dl_sap_length = sap_length;

                if (gld->gld_state == DL_IDLE) {
                        /*
                         * If we are bound to a non-LLC SAP on any medium
                         * other than Ethernet, then we need room for a
                         * SNAP header.  So we have to adjust the MTU size
                         * accordingly.  XXX I suppose this should be done
                         * in gldutil.c, but it seems likely that this will
                         * always be true for everything GLD supports but
                         * Ethernet.  Check this if you add another medium.
                         */
                        if ((macinfo->gldm_type == DL_TPR ||
                            macinfo->gldm_type == DL_FDDI) &&
                            gld->gld_ethertype)
                                dlp->dl_max_sdu -= LLC_SNAP_HDR_LEN;

                        /* copy macaddr and sap */
                        dlp->dl_addr_offset = addr_offset;

                        mac_copy(mac_pvt->curr_macaddr, mp->b_rptr +
                            addr_offset, macinfo->gldm_addrlen);
                        sapp = mp->b_rptr + addr_offset +
                            macinfo->gldm_addrlen;
                        *(ushort_t *)sapp = gld->gld_sap;
                } else {
                        dlp->dl_addr_offset = 0;
                }

                /* copy broadcast addr */
                dlp->dl_brdcst_addr_length = macinfo->gldm_addrlen;
                dlp->dl_brdcst_addr_offset = brdcst_offset;
                mac_copy((caddr_t)macinfo->gldm_broadcast_addr,
                    mp->b_rptr + brdcst_offset, brdcst_length);
        } else {
                /*
                 * No PPA is attached.
                 * The best we can do is use the values provided
                 * by the first mac that called gld_register.
                 */
                dlp->dl_min_sdu = glddev->gld_minsdu;
                dlp->dl_max_sdu = glddev->gld_maxsdu;
                dlp->dl_mac_type = glddev->gld_type;
                dlp->dl_addr_length = addr_length + abs(sap_length);
                dlp->dl_sap_length = sap_length;
                dlp->dl_addr_offset = 0;
                dlp->dl_brdcst_addr_offset = brdcst_offset;
                dlp->dl_brdcst_addr_length = brdcst_length;
                mac_copy((caddr_t)glddev->gld_broadcast,
                    mp->b_rptr + brdcst_offset, brdcst_length);
        }
        qreply(q, mp);
        return (GLDE_OK);
}

/*
 * gld_unitdata (q, mp)
 * send a datagram.  Destination address/lsap is in M_PROTO
 * message (first mblock), data is in remainder of message.
 *
 */
static int
gld_unitdata(queue_t *q, mblk_t *mp)
{
        gld_t *gld = (gld_t *)q->q_ptr;
        dl_unitdata_req_t *dlp = (dl_unitdata_req_t *)mp->b_rptr;
        gld_mac_info_t *macinfo = gld->gld_mac_info;
        size_t  msglen;
        mblk_t  *nmp;
        gld_interface_t *ifp;
        uint32_t start;
        uint32_t stuff;
        uint32_t end;
        uint32_t value;
        uint32_t flags;
        uint32_t upri;

#ifdef GLD_DEBUG
        if (gld_debug & GLDTRACE)
                cmn_err(CE_NOTE, "gld_unitdata(%p %p)", (void *)q, (void *)mp);
#endif

        if (gld->gld_state != DL_IDLE) {
#ifdef GLD_DEBUG
                if (gld_debug & GLDERRS)
                        cmn_err(CE_NOTE, "gld_unitdata: wrong state (%d)",
                            gld->gld_state);
#endif
                dluderrorind(q, mp, mp->b_rptr + dlp->dl_dest_addr_offset,
                    dlp->dl_dest_addr_length, DL_OUTSTATE, 0);
                return (GLDE_OK);
        }
        ASSERT(macinfo != NULL);

        if (!MBLKIN(mp, dlp->dl_dest_addr_offset, dlp->dl_dest_addr_length) ||
            dlp->dl_dest_addr_length !=
            macinfo->gldm_addrlen + abs(macinfo->gldm_saplen)) {
                dluderrorind(q, mp, mp->b_rptr + dlp->dl_dest_addr_offset,
                    dlp->dl_dest_addr_length, DL_BADADDR, 0);
                return (GLDE_OK);
        }

        upri = dlp->dl_priority.dl_max;

        msglen = msgdsize(mp);
        if (msglen == 0 || msglen > macinfo->gldm_maxpkt) {
#ifdef GLD_DEBUG
                if (gld_debug & GLDERRS)
                        cmn_err(CE_NOTE, "gld_unitdata: bad msglen (%d)",
                            (int)msglen);
#endif
                dluderrorind(q, mp, mp->b_rptr + dlp->dl_dest_addr_offset,
                    dlp->dl_dest_addr_length, DL_BADDATA, 0);
                return (GLDE_OK);
        }

        ASSERT(mp->b_cont != NULL);     /* because msgdsize(mp) is nonzero */

        ifp = ((gld_mac_pvt_t *)macinfo->gldm_mac_pvt)->interfacep;

        /* grab any checksum information that may be present */
        hcksum_retrieve(mp->b_cont, NULL, NULL, &start, &stuff, &end,
            &value, &flags);

        /*
         * Prepend a valid header for transmission
         */
        if ((nmp = (*ifp->mkunitdata)(gld, mp)) == NULL) {
#ifdef GLD_DEBUG
                if (gld_debug & GLDERRS)
                        cmn_err(CE_NOTE, "gld_unitdata: mkunitdata failed.");
#endif
                dluderrorind(q, mp, mp->b_rptr + dlp->dl_dest_addr_offset,
                    dlp->dl_dest_addr_length, DL_SYSERR, ENOSR);
                return (GLDE_OK);
        }

        /* apply any checksum information to the first block in the chain */
        (void) hcksum_assoc(nmp, NULL, NULL, start, stuff, end, value,
            flags, 0);

        GLD_CLEAR_MBLK_VTAG(nmp);
        if (gld_start(q, nmp, GLD_WSRV, upri) == GLD_NORESOURCES) {
                qenable(q);
                return (GLDE_RETRY);
        }

        return (GLDE_OK);
}

/*
 * gldattach(q, mp)
 * DLPI DL_ATTACH_REQ
 * this attaches the stream to a PPA
 */
static int
gldattach(queue_t *q, mblk_t *mp)
{
        dl_attach_req_t *at;
        gld_mac_info_t *macinfo;
        gld_t  *gld = (gld_t *)q->q_ptr;
        glddev_t *glddev;
        gld_mac_pvt_t *mac_pvt;
        uint32_t ppa;
        uint32_t vid;
        gld_vlan_t *vlan;

        at = (dl_attach_req_t *)mp->b_rptr;

        if (gld->gld_state != DL_UNATTACHED)
                return (DL_OUTSTATE);

        ASSERT(!gld->gld_mac_info);

        ppa = at->dl_ppa % GLD_VLAN_SCALE;      /* 0 .. 999     */
        vid = at->dl_ppa / GLD_VLAN_SCALE;      /* 0 .. 4094    */
        if (vid > VLAN_VID_MAX)
                return (DL_BADPPA);

        glddev = gld->gld_device;
        mutex_enter(&glddev->gld_devlock);
        for (macinfo = glddev->gld_mac_next;
            macinfo != (gld_mac_info_t *)&glddev->gld_mac_next;
            macinfo = macinfo->gldm_next) {
                int inst;

                ASSERT(macinfo != NULL);
                if (macinfo->gldm_ppa != ppa)
                        continue;

                if (!(macinfo->gldm_GLD_flags & GLD_MAC_READY))
                        continue;       /* this one's not ready yet */

                /*
                 * VLAN sanity check
                 */
                if (vid != VLAN_VID_NONE && !VLAN_CAPABLE(macinfo)) {
                        mutex_exit(&glddev->gld_devlock);
                        return (DL_BADPPA);
                }

                /*
                 * We found the correct PPA, hold the instance
                 */
                inst = ddi_get_instance(macinfo->gldm_devinfo);
                if (inst == -1 || qassociate(q, inst) != 0) {
                        mutex_exit(&glddev->gld_devlock);
                        return (DL_BADPPA);
                }

                /* Take the stream off the per-driver-class list */
                gldremque(gld);

                /*
                 * We must hold the lock to prevent multiple calls
                 * to the reset and start routines.
                 */
                GLDM_LOCK(macinfo, RW_WRITER);

                gld->gld_mac_info = macinfo;

                if (macinfo->gldm_send_tagged != NULL)
                        gld->gld_send = macinfo->gldm_send_tagged;
                else
                        gld->gld_send = macinfo->gldm_send;

                if ((vlan = gld_get_vlan(macinfo, vid)) == NULL) {
                        GLDM_UNLOCK(macinfo);
                        gldinsque(gld, glddev->gld_str_prev);
                        mutex_exit(&glddev->gld_devlock);
                        (void) qassociate(q, -1);
                        return (DL_BADPPA);
                }

                mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
                if (!mac_pvt->started) {
                        if (gld_start_mac(macinfo) != GLD_SUCCESS) {
                                gld_rem_vlan(vlan);
                                GLDM_UNLOCK(macinfo);
                                gldinsque(gld, glddev->gld_str_prev);
                                mutex_exit(&glddev->gld_devlock);
                                dlerrorack(q, mp, DL_ATTACH_REQ, DL_SYSERR,
                                    EIO);
                                (void) qassociate(q, -1);
                                return (GLDE_OK);
                        }
                }

                gld->gld_vlan = vlan;
                vlan->gldv_nstreams++;
                gldinsque(gld, vlan->gldv_str_prev);
                gld->gld_state = DL_UNBOUND;
                GLDM_UNLOCK(macinfo);

#ifdef GLD_DEBUG
                if (gld_debug & GLDPROT) {
                        cmn_err(CE_NOTE, "gldattach(%p, %p, PPA = %d)",
                            (void *)q, (void *)mp, macinfo->gldm_ppa);
                }
#endif
                mutex_exit(&glddev->gld_devlock);
                dlokack(q, mp, DL_ATTACH_REQ);
                return (GLDE_OK);
        }
        mutex_exit(&glddev->gld_devlock);
        return (DL_BADPPA);
}

/*
 * gldunattach(q, mp)
 * DLPI DL_DETACH_REQ
 * detaches the mac layer from the stream
 */
int
gldunattach(queue_t *q, mblk_t *mp)
{
        gld_t  *gld = (gld_t *)q->q_ptr;
        glddev_t *glddev = gld->gld_device;
        gld_mac_info_t *macinfo = gld->gld_mac_info;
        int     state = gld->gld_state;
        int     i;
        gld_mac_pvt_t *mac_pvt;
        gld_vlan_t *vlan;
        boolean_t phys_off;
        boolean_t mult_off;
        int op = GLD_MAC_PROMISC_NOOP;

        if (state != DL_UNBOUND)
                return (DL_OUTSTATE);

        ASSERT(macinfo != NULL);
        ASSERT(gld->gld_sap == 0);
        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;

#ifdef GLD_DEBUG
        if (gld_debug & GLDPROT) {
                cmn_err(CE_NOTE, "gldunattach(%p, %p, PPA = %d)",
                    (void *)q, (void *)mp, macinfo->gldm_ppa);
        }
#endif

        GLDM_LOCK(macinfo, RW_WRITER);

        if (gld->gld_mcast) {
                for (i = 0; i < gld->gld_multicnt; i++) {
                        gld_mcast_t *mcast;

                        if ((mcast = gld->gld_mcast[i]) != NULL) {
                                ASSERT(mcast->gldm_refcnt);
                                gld_send_disable_multi(macinfo, mcast);
                        }
                }
                kmem_free(gld->gld_mcast,
                    sizeof (gld_mcast_t *) * gld->gld_multicnt);
                gld->gld_mcast = NULL;
                gld->gld_multicnt = 0;
        }

        /* decide if we need to turn off any promiscuity */
        phys_off = (gld->gld_flags & GLD_PROM_PHYS &&
            --mac_pvt->nprom == 0);
        mult_off = (gld->gld_flags & GLD_PROM_MULT &&
            --mac_pvt->nprom_multi == 0);

        if (phys_off) {
                op = (mac_pvt->nprom_multi == 0) ? GLD_MAC_PROMISC_NONE :
                    GLD_MAC_PROMISC_MULTI;
        } else if (mult_off) {
                op = (mac_pvt->nprom == 0) ? GLD_MAC_PROMISC_NONE :
                    GLD_MAC_PROMISC_NOOP;       /* phys overrides multi */
        }

        if (op != GLD_MAC_PROMISC_NOOP)
                (void) (*macinfo->gldm_set_promiscuous)(macinfo, op);

        vlan = (gld_vlan_t *)gld->gld_vlan;
        if (gld->gld_flags & GLD_PROM_PHYS)
                vlan->gldv_nprom--;
        if (gld->gld_flags & GLD_PROM_MULT)
                vlan->gldv_nprom--;
        if (gld->gld_flags & GLD_PROM_SAP) {
                vlan->gldv_nprom--;
                vlan->gldv_nvlan_sap--;
        }

        gld->gld_flags &= ~(GLD_PROM_PHYS | GLD_PROM_SAP | GLD_PROM_MULT);

        GLDM_UNLOCK(macinfo);

        if (phys_off)
                gld_notify_ind(macinfo, DL_NOTE_PROMISC_OFF_PHYS, NULL);

        /*
         * We need to hold both locks when modifying the mac stream list
         * to protect findminor as well as everyone else.
         */
        mutex_enter(&glddev->gld_devlock);
        GLDM_LOCK(macinfo, RW_WRITER);

        /* disassociate this stream with its vlan and underlying mac */
        gldremque(gld);

        if (--vlan->gldv_nstreams == 0) {
                gld_rem_vlan(vlan);
                gld->gld_vlan = NULL;
        }

        gld->gld_mac_info = NULL;
        gld->gld_state = DL_UNATTACHED;

        /* cleanup mac layer if last vlan */
        if (mac_pvt->nvlan == 0) {
                gld_stop_mac(macinfo);
                macinfo->gldm_GLD_flags &= ~GLD_INTR_WAIT;
        }

        /* make sure no references to this gld for gld_v0_sched */
        if (mac_pvt->last_sched == gld)
                mac_pvt->last_sched = NULL;

        GLDM_UNLOCK(macinfo);

        /* put the stream on the unattached Style 2 list */
        gldinsque(gld, glddev->gld_str_prev);

        mutex_exit(&glddev->gld_devlock);

        /* There will be no mp if we were called from close */
        if (mp) {
                dlokack(q, mp, DL_DETACH_REQ);
        }
        if (gld->gld_style == DL_STYLE2)
                (void) qassociate(q, -1);
        return (GLDE_OK);
}

/*
 * gld_enable_multi (q, mp)
 * Enables multicast address on the stream.  If the mac layer
 * isn't enabled for this address, enable at that level as well.
 */
static int
gld_enable_multi(queue_t *q, mblk_t *mp)
{
        gld_t  *gld = (gld_t *)q->q_ptr;
        glddev_t *glddev;
        gld_mac_info_t *macinfo = gld->gld_mac_info;
        unsigned char *maddr;
        dl_enabmulti_req_t *multi;
        gld_mcast_t *mcast;
        int     i, rc;
        gld_mac_pvt_t *mac_pvt;

#ifdef GLD_DEBUG
        if (gld_debug & GLDPROT) {
                cmn_err(CE_NOTE, "gld_enable_multi(%p, %p)", (void *)q,
                    (void *)mp);
        }
#endif

        if (gld->gld_state == DL_UNATTACHED)
                return (DL_OUTSTATE);

        ASSERT(macinfo != NULL);
        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;

        if (macinfo->gldm_set_multicast == NULL) {
                return (DL_UNSUPPORTED);
        }

        multi = (dl_enabmulti_req_t *)mp->b_rptr;

        if (!MBLKIN(mp, multi->dl_addr_offset, multi->dl_addr_length) ||
            multi->dl_addr_length != macinfo->gldm_addrlen)
                return (DL_BADADDR);

        /* request appears to be valid */

        glddev = mac_pvt->major_dev;
        ASSERT(glddev == gld->gld_device);

        maddr = mp->b_rptr + multi->dl_addr_offset;

        /*
         * The multicast addresses live in a per-device table, along
         * with a reference count.  Each stream has a table that
         * points to entries in the device table, with the reference
         * count reflecting the number of streams pointing at it.  If
         * this multicast address is already in the per-device table,
         * all we have to do is point at it.
         */
        GLDM_LOCK(macinfo, RW_WRITER);

        /* does this address appear in current table? */
        if (gld->gld_mcast == NULL) {
                /* no mcast addresses -- allocate table */
                gld->gld_mcast = GLD_GETSTRUCT(gld_mcast_t *,
                    glddev->gld_multisize);
                if (gld->gld_mcast == NULL) {
                        GLDM_UNLOCK(macinfo);
                        dlerrorack(q, mp, DL_ENABMULTI_REQ, DL_SYSERR, ENOSR);
                        return (GLDE_OK);
                }
                gld->gld_multicnt = glddev->gld_multisize;
        } else {
                for (i = 0; i < gld->gld_multicnt; i++) {
                        if (gld->gld_mcast[i] &&
                            mac_eq(gld->gld_mcast[i]->gldm_addr,
                            maddr, macinfo->gldm_addrlen)) {
                                /* this is a match -- just succeed */
                                ASSERT(gld->gld_mcast[i]->gldm_refcnt);
                                GLDM_UNLOCK(macinfo);
                                dlokack(q, mp, DL_ENABMULTI_REQ);
                                return (GLDE_OK);
                        }
                }
        }

        /*
         * it wasn't in the stream so check to see if the mac layer has it
         */
        mcast = NULL;
        if (mac_pvt->mcast_table == NULL) {
                mac_pvt->mcast_table = GLD_GETSTRUCT(gld_mcast_t,
                    glddev->gld_multisize);
                if (mac_pvt->mcast_table == NULL) {
                        GLDM_UNLOCK(macinfo);
                        dlerrorack(q, mp, DL_ENABMULTI_REQ, DL_SYSERR, ENOSR);
                        return (GLDE_OK);
                }
        } else {
                for (i = 0; i < glddev->gld_multisize; i++) {
                        if (mac_pvt->mcast_table[i].gldm_refcnt &&
                            mac_eq(mac_pvt->mcast_table[i].gldm_addr,
                            maddr, macinfo->gldm_addrlen)) {
                                mcast = &mac_pvt->mcast_table[i];
                                break;
                        }
                }
        }
        if (mcast == NULL) {
                /* not in mac layer -- find an empty mac slot to fill in */
                for (i = 0; i < glddev->gld_multisize; i++) {
                        if (mac_pvt->mcast_table[i].gldm_refcnt == 0) {
                                mcast = &mac_pvt->mcast_table[i];
                                mac_copy(maddr, mcast->gldm_addr,
                                    macinfo->gldm_addrlen);
                                break;
                        }
                }
        }
        if (mcast == NULL) {
                /* couldn't get a mac layer slot */
                GLDM_UNLOCK(macinfo);
                return (DL_TOOMANY);
        }

        /* now we have a mac layer slot in mcast -- get a stream slot */
        for (i = 0; i < gld->gld_multicnt; i++) {
                if (gld->gld_mcast[i] != NULL)
                        continue;
                /* found an empty slot */
                if (!mcast->gldm_refcnt) {
                        /* set mcast in hardware */
                        unsigned char cmaddr[GLD_MAX_ADDRLEN];

                        ASSERT(sizeof (cmaddr) >= macinfo->gldm_addrlen);
                        cmac_copy(maddr, cmaddr,
                            macinfo->gldm_addrlen, macinfo);

                        rc = (*macinfo->gldm_set_multicast)
                            (macinfo, cmaddr, GLD_MULTI_ENABLE);
                        if (rc == GLD_NOTSUPPORTED) {
                                GLDM_UNLOCK(macinfo);
                                return (DL_NOTSUPPORTED);
                        } else if (rc == GLD_NORESOURCES) {
                                GLDM_UNLOCK(macinfo);
                                return (DL_TOOMANY);
                        } else if (rc == GLD_BADARG) {
                                GLDM_UNLOCK(macinfo);
                                return (DL_BADADDR);
                        } else if (rc == GLD_RETRY) {
                                /*
                                 * The putbq and gld_xwait must be
                                 * within the lock to prevent races
                                 * with gld_sched.
                                 */
                                (void) putbq(q, mp);
                                gld->gld_xwait = B_TRUE;
                                GLDM_UNLOCK(macinfo);
                                return (GLDE_RETRY);
                        } else if (rc != GLD_SUCCESS) {
                                GLDM_UNLOCK(macinfo);
                                dlerrorack(q, mp, DL_ENABMULTI_REQ,
                                    DL_SYSERR, EIO);
                                return (GLDE_OK);
                        }
                }
                gld->gld_mcast[i] = mcast;
                mcast->gldm_refcnt++;
                GLDM_UNLOCK(macinfo);
                dlokack(q, mp, DL_ENABMULTI_REQ);
                return (GLDE_OK);
        }

        /* couldn't get a stream slot */
        GLDM_UNLOCK(macinfo);
        return (DL_TOOMANY);
}


/*
 * gld_disable_multi (q, mp)
 * Disable the multicast address on the stream.  If last
 * reference for the mac layer, disable there as well.
 */
static int
gld_disable_multi(queue_t *q, mblk_t *mp)
{
        gld_t  *gld;
        gld_mac_info_t *macinfo;
        unsigned char *maddr;
        dl_disabmulti_req_t *multi;
        int i;
        gld_mcast_t *mcast;

#ifdef GLD_DEBUG
        if (gld_debug & GLDPROT) {
                cmn_err(CE_NOTE, "gld_disable_multi(%p, %p)", (void *)q,
                    (void *)mp);
        }
#endif

        gld = (gld_t *)q->q_ptr;
        if (gld->gld_state == DL_UNATTACHED)
                return (DL_OUTSTATE);

        macinfo = gld->gld_mac_info;
        ASSERT(macinfo != NULL);
        if (macinfo->gldm_set_multicast == NULL) {
                return (DL_UNSUPPORTED);
        }

        multi = (dl_disabmulti_req_t *)mp->b_rptr;

        if (!MBLKIN(mp, multi->dl_addr_offset, multi->dl_addr_length) ||
            multi->dl_addr_length != macinfo->gldm_addrlen)
                return (DL_BADADDR);

        maddr = mp->b_rptr + multi->dl_addr_offset;

        /* request appears to be valid */
        /* does this address appear in current table? */
        GLDM_LOCK(macinfo, RW_WRITER);
        if (gld->gld_mcast != NULL) {
                for (i = 0; i < gld->gld_multicnt; i++)
                        if (((mcast = gld->gld_mcast[i]) != NULL) &&
                            mac_eq(mcast->gldm_addr,
                            maddr, macinfo->gldm_addrlen)) {
                                ASSERT(mcast->gldm_refcnt);
                                gld_send_disable_multi(macinfo, mcast);
                                gld->gld_mcast[i] = NULL;
                                GLDM_UNLOCK(macinfo);
                                dlokack(q, mp, DL_DISABMULTI_REQ);
                                return (GLDE_OK);
                        }
        }
        GLDM_UNLOCK(macinfo);
        return (DL_NOTENAB); /* not an enabled address */
}

/*
 * gld_send_disable_multi(macinfo, mcast)
 * this function is used to disable a multicast address if the reference
 * count goes to zero. The disable request will then be forwarded to the
 * lower stream.
 */
static void
gld_send_disable_multi(gld_mac_info_t *macinfo, gld_mcast_t *mcast)
{
        ASSERT(macinfo != NULL);
        ASSERT(GLDM_LOCK_HELD_WRITE(macinfo));
        ASSERT(mcast != NULL);
        ASSERT(mcast->gldm_refcnt);

        if (!mcast->gldm_refcnt) {
                return;                 /* "cannot happen" */
        }

        if (--mcast->gldm_refcnt > 0) {
                return;
        }

        /*
         * This must be converted from canonical form to device form.
         * The refcnt is now zero so we can trash the data.
         */
        if (macinfo->gldm_options & GLDOPT_CANONICAL_ADDR)
                gld_bitreverse(mcast->gldm_addr, macinfo->gldm_addrlen);

        /* XXX Ought to check for GLD_NORESOURCES or GLD_FAILURE */
        (void) (*macinfo->gldm_set_multicast)
            (macinfo, mcast->gldm_addr, GLD_MULTI_DISABLE);
}

/*
 * gld_promisc (q, mp, req, on)
 *      enable or disable the use of promiscuous mode with the hardware
 */
static int
gld_promisc(queue_t *q, mblk_t *mp, t_uscalar_t req, boolean_t on)
{
        gld_t *gld;
        gld_mac_info_t *macinfo;
        gld_mac_pvt_t *mac_pvt;
        gld_vlan_t *vlan;
        union DL_primitives *prim;
        int macrc = GLD_SUCCESS;
        int dlerr = GLDE_OK;
        int op = GLD_MAC_PROMISC_NOOP;

#ifdef GLD_DEBUG
        if (gld_debug & GLDTRACE)
                cmn_err(CE_NOTE, "gld_promisc(%p, %p, %d, %d)",
                    (void *)q, (void *)mp, req, on);
#endif

        ASSERT(mp != NULL);
        prim = (union DL_primitives *)mp->b_rptr;

        /* XXX I think spec allows promisc in unattached state */
        gld = (gld_t *)q->q_ptr;
        if (gld->gld_state == DL_UNATTACHED)
                return (DL_OUTSTATE);

        macinfo = gld->gld_mac_info;
        ASSERT(macinfo != NULL);
        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;

        vlan = (gld_vlan_t *)gld->gld_vlan;
        ASSERT(vlan != NULL);

        GLDM_LOCK(macinfo, RW_WRITER);

        /*
         * Work out what request (if any) has to be made to the MAC layer
         */
        if (on) {
                switch (prim->promiscon_req.dl_level) {
                default:
                        dlerr = DL_UNSUPPORTED; /* this is an error */
                        break;

                case DL_PROMISC_PHYS:
                        if (mac_pvt->nprom == 0)
                                op = GLD_MAC_PROMISC_PHYS;
                        break;

                case DL_PROMISC_MULTI:
                        if (mac_pvt->nprom_multi == 0)
                                if (mac_pvt->nprom == 0)
                                        op = GLD_MAC_PROMISC_MULTI;
                        break;

                case DL_PROMISC_SAP:
                        /* We can do this without reference to the MAC */
                        break;
                }
        } else {
                switch (prim->promiscoff_req.dl_level) {
                default:
                        dlerr = DL_UNSUPPORTED; /* this is an error */
                        break;

                case DL_PROMISC_PHYS:
                        if (!(gld->gld_flags & GLD_PROM_PHYS))
                                dlerr = DL_NOTENAB;
                        else if (mac_pvt->nprom == 1)
                                if (mac_pvt->nprom_multi)
                                        op = GLD_MAC_PROMISC_MULTI;
                                else
                                        op = GLD_MAC_PROMISC_NONE;
                        break;

                case DL_PROMISC_MULTI:
                        if (!(gld->gld_flags & GLD_PROM_MULT))
                                dlerr = DL_NOTENAB;
                        else if (mac_pvt->nprom_multi == 1)
                                if (mac_pvt->nprom == 0)
                                        op = GLD_MAC_PROMISC_NONE;
                        break;

                case DL_PROMISC_SAP:
                        if (!(gld->gld_flags & GLD_PROM_SAP))
                                dlerr = DL_NOTENAB;

                        /* We can do this without reference to the MAC */
                        break;
                }
        }

        /*
         * The request was invalid in some way so no need to continue.
         */
        if (dlerr != GLDE_OK) {
                GLDM_UNLOCK(macinfo);
                return (dlerr);
        }

        /*
         * Issue the request to the MAC layer, if required
         */
        if (op != GLD_MAC_PROMISC_NOOP) {
                macrc = (*macinfo->gldm_set_promiscuous)(macinfo, op);
        }

        /*
         * On success, update the appropriate flags & refcounts
         */
        if (macrc == GLD_SUCCESS) {
                if (on) {
                        switch (prim->promiscon_req.dl_level) {
                        case DL_PROMISC_PHYS:
                                mac_pvt->nprom++;
                                vlan->gldv_nprom++;
                                gld->gld_flags |= GLD_PROM_PHYS;
                                break;

                        case DL_PROMISC_MULTI:
                                mac_pvt->nprom_multi++;
                                vlan->gldv_nprom++;
                                gld->gld_flags |= GLD_PROM_MULT;
                                break;

                        case DL_PROMISC_SAP:
                                gld->gld_flags |= GLD_PROM_SAP;
                                vlan->gldv_nprom++;
                                vlan->gldv_nvlan_sap++;
                                break;

                        default:
                                break;
                        }
                } else {
                        switch (prim->promiscoff_req.dl_level) {
                        case DL_PROMISC_PHYS:
                                mac_pvt->nprom--;
                                vlan->gldv_nprom--;
                                gld->gld_flags &= ~GLD_PROM_PHYS;
                                break;

                        case DL_PROMISC_MULTI:
                                mac_pvt->nprom_multi--;
                                vlan->gldv_nprom--;
                                gld->gld_flags &= ~GLD_PROM_MULT;
                                break;

                        case DL_PROMISC_SAP:
                                gld->gld_flags &= ~GLD_PROM_SAP;
                                vlan->gldv_nvlan_sap--;
                                vlan->gldv_nprom--;
                                break;

                        default:
                                break;
                        }
                }
        } else if (macrc == GLD_RETRY) {
                /*
                 * The putbq and gld_xwait must be within the lock to
                 * prevent races with gld_sched.
                 */
                (void) putbq(q, mp);
                gld->gld_xwait = B_TRUE;
        }

        GLDM_UNLOCK(macinfo);

        /*
         * Finally, decide how to reply.
         *
         * If <macrc> is not GLD_SUCCESS, the request was put to the MAC
         * layer but failed.  In such cases, we can return a DL_* error
         * code and let the caller send an error-ack reply upstream, or
         * we can send a reply here and then return GLDE_OK so that the
         * caller doesn't also respond.
         *
         * If physical-promiscuous mode was (successfully) switched on or
         * off, send a notification (DL_NOTIFY_IND) to anyone interested.
         */
        switch (macrc) {
        case GLD_NOTSUPPORTED:
                return (DL_NOTSUPPORTED);

        case GLD_NORESOURCES:
                dlerrorack(q, mp, req, DL_SYSERR, ENOSR);
                return (GLDE_OK);

        case GLD_RETRY:
                return (GLDE_RETRY);

        default:
                dlerrorack(q, mp, req, DL_SYSERR, EIO);
                return (GLDE_OK);

        case GLD_SUCCESS:
                dlokack(q, mp, req);
                break;
        }

        switch (op) {
        case GLD_MAC_PROMISC_NOOP:
                break;

        case GLD_MAC_PROMISC_PHYS:
                gld_notify_ind(macinfo, DL_NOTE_PROMISC_ON_PHYS, NULL);
                break;

        default:
                gld_notify_ind(macinfo, DL_NOTE_PROMISC_OFF_PHYS, NULL);
                break;
        }

        return (GLDE_OK);
}

/*
 * gld_physaddr()
 *      get the current or factory physical address value
 */
static int
gld_physaddr(queue_t *q, mblk_t *mp)
{
        gld_t *gld = (gld_t *)q->q_ptr;
        gld_mac_info_t *macinfo;
        union DL_primitives *prim = (union DL_primitives *)mp->b_rptr;
        unsigned char addr[GLD_MAX_ADDRLEN];

        if (gld->gld_state == DL_UNATTACHED)
                return (DL_OUTSTATE);

        macinfo = (gld_mac_info_t *)gld->gld_mac_info;
        ASSERT(macinfo != NULL);
        ASSERT(macinfo->gldm_addrlen <= GLD_MAX_ADDRLEN);

        switch (prim->physaddr_req.dl_addr_type) {
        case DL_FACT_PHYS_ADDR:
                mac_copy((caddr_t)macinfo->gldm_vendor_addr,
                    (caddr_t)addr, macinfo->gldm_addrlen);
                break;
        case DL_CURR_PHYS_ADDR:
                /* make a copy so we don't hold the lock across qreply */
                GLDM_LOCK(macinfo, RW_WRITER);
                mac_copy((caddr_t)
                    ((gld_mac_pvt_t *)macinfo->gldm_mac_pvt)->curr_macaddr,
                    (caddr_t)addr, macinfo->gldm_addrlen);
                GLDM_UNLOCK(macinfo);
                break;
        default:
                return (DL_BADPRIM);
        }
        dlphysaddrack(q, mp, (caddr_t)addr, macinfo->gldm_addrlen);
        return (GLDE_OK);
}

/*
 * gld_setaddr()
 *      change the hardware's physical address to a user specified value
 */
static int
gld_setaddr(queue_t *q, mblk_t *mp)
{
        gld_t *gld = (gld_t *)q->q_ptr;
        gld_mac_info_t *macinfo;
        gld_mac_pvt_t *mac_pvt;
        union DL_primitives *prim = (union DL_primitives *)mp->b_rptr;
        unsigned char *addr;
        unsigned char cmaddr[GLD_MAX_ADDRLEN];
        int rc;
        gld_vlan_t *vlan;

        if (gld->gld_state == DL_UNATTACHED)
                return (DL_OUTSTATE);

        vlan = (gld_vlan_t *)gld->gld_vlan;
        ASSERT(vlan != NULL);

        if (vlan->gldv_id != VLAN_VID_NONE)
                return (DL_NOTSUPPORTED);

        macinfo = (gld_mac_info_t *)gld->gld_mac_info;
        ASSERT(macinfo != NULL);
        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;

        if (!MBLKIN(mp, prim->set_physaddr_req.dl_addr_offset,
            prim->set_physaddr_req.dl_addr_length) ||
            prim->set_physaddr_req.dl_addr_length != macinfo->gldm_addrlen)
                return (DL_BADADDR);

        GLDM_LOCK(macinfo, RW_WRITER);

        /* now do the set at the hardware level */
        addr = mp->b_rptr + prim->set_physaddr_req.dl_addr_offset;
        ASSERT(sizeof (cmaddr) >= macinfo->gldm_addrlen);
        cmac_copy(addr, cmaddr, macinfo->gldm_addrlen, macinfo);

        rc = (*macinfo->gldm_set_mac_addr)(macinfo, cmaddr);
        if (rc == GLD_SUCCESS)
                mac_copy(addr, mac_pvt->curr_macaddr,
                    macinfo->gldm_addrlen);

        GLDM_UNLOCK(macinfo);

        switch (rc) {
        case GLD_SUCCESS:
                break;
        case GLD_NOTSUPPORTED:
                return (DL_NOTSUPPORTED);
        case GLD_BADARG:
                return (DL_BADADDR);
        case GLD_NORESOURCES:
                dlerrorack(q, mp, DL_SET_PHYS_ADDR_REQ, DL_SYSERR, ENOSR);
                return (GLDE_OK);
        default:
                dlerrorack(q, mp, DL_SET_PHYS_ADDR_REQ, DL_SYSERR, EIO);
                return (GLDE_OK);
        }

        gld_notify_ind(macinfo, DL_NOTE_PHYS_ADDR, NULL);

        dlokack(q, mp, DL_SET_PHYS_ADDR_REQ);
        return (GLDE_OK);
}

int
gld_get_statistics(queue_t *q, mblk_t *mp)
{
        dl_get_statistics_ack_t *dlsp;
        gld_t  *gld = (gld_t *)q->q_ptr;
        gld_mac_info_t *macinfo = gld->gld_mac_info;
        gld_mac_pvt_t *mac_pvt;

        if (gld->gld_state == DL_UNATTACHED)
                return (DL_OUTSTATE);

        ASSERT(macinfo != NULL);

        mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        (void) gld_update_kstat(mac_pvt->kstatp, KSTAT_READ);

        mp = mexchange(q, mp, DL_GET_STATISTICS_ACK_SIZE +
            sizeof (struct gldkstats), M_PCPROTO, DL_GET_STATISTICS_ACK);

        if (mp == NULL)
                return (GLDE_OK);       /* mexchange already sent merror */

        dlsp = (dl_get_statistics_ack_t *)mp->b_rptr;
        dlsp->dl_primitive = DL_GET_STATISTICS_ACK;
        dlsp->dl_stat_length = sizeof (struct gldkstats);
        dlsp->dl_stat_offset = DL_GET_STATISTICS_ACK_SIZE;

        GLDM_LOCK(macinfo, RW_WRITER);
        bcopy(mac_pvt->kstatp->ks_data,
            (mp->b_rptr + DL_GET_STATISTICS_ACK_SIZE),
            sizeof (struct gldkstats));
        GLDM_UNLOCK(macinfo);

        qreply(q, mp);
        return (GLDE_OK);
}

/* =================================================== */
/* misc utilities, some requiring various mutexes held */
/* =================================================== */

/*
 * Initialize and start the driver.
 */
static int
gld_start_mac(gld_mac_info_t *macinfo)
{
        int     rc;
        unsigned char cmaddr[GLD_MAX_ADDRLEN];
        gld_mac_pvt_t *mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;

        ASSERT(GLDM_LOCK_HELD_WRITE(macinfo));
        ASSERT(!mac_pvt->started);

        rc = (*macinfo->gldm_reset)(macinfo);
        if (rc != GLD_SUCCESS)
                return (GLD_FAILURE);

        /* set the addr after we reset the device */
        ASSERT(sizeof (cmaddr) >= macinfo->gldm_addrlen);
        cmac_copy(((gld_mac_pvt_t *)macinfo->gldm_mac_pvt)
            ->curr_macaddr, cmaddr, macinfo->gldm_addrlen, macinfo);

        rc = (*macinfo->gldm_set_mac_addr)(macinfo, cmaddr);
        ASSERT(rc != GLD_BADARG);  /* this address was good before */
        if (rc != GLD_SUCCESS && rc != GLD_NOTSUPPORTED)
                return (GLD_FAILURE);

        rc = (*macinfo->gldm_start)(macinfo);
        if (rc != GLD_SUCCESS)
                return (GLD_FAILURE);

        mac_pvt->started = B_TRUE;
        return (GLD_SUCCESS);
}

/*
 * Stop the driver.
 */
static void
gld_stop_mac(gld_mac_info_t *macinfo)
{
        gld_mac_pvt_t *mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;

        ASSERT(GLDM_LOCK_HELD_WRITE(macinfo));
        ASSERT(mac_pvt->started);

        (void) (*macinfo->gldm_stop)(macinfo);

        mac_pvt->started = B_FALSE;
}


/*
 * gld_set_ipq will set a pointer to the queue which is bound to the
 * IP sap if:
 * o the device type is ethernet or IPoIB.
 * o there is no stream in SAP promiscuous mode.
 * o there is exactly one stream bound to the IP sap.
 * o the stream is in "fastpath" mode.
 */
static void
gld_set_ipq(gld_t *gld)
{
        gld_vlan_t      *vlan;
        gld_mac_info_t  *macinfo = gld->gld_mac_info;
        gld_t           *ip_gld = NULL;
        uint_t          ipq_candidates = 0;
        gld_t           *ipv6_gld = NULL;
        uint_t          ipv6q_candidates = 0;

        ASSERT(GLDM_LOCK_HELD_WRITE(macinfo));

        /* The ipq code in gld_recv() is intimate with ethernet/IPoIB */
        if (((macinfo->gldm_type != DL_ETHER) &&
            (macinfo->gldm_type != DL_IB)) ||
            (gld_global_options & GLD_OPT_NO_IPQ))
                return;

        vlan = (gld_vlan_t *)gld->gld_vlan;
        ASSERT(vlan != NULL);

        /* clear down any previously defined ipqs */
        vlan->gldv_ipq = NULL;
        vlan->gldv_ipv6q = NULL;

        /* Try to find a single stream eligible to receive IP packets */
        for (gld = vlan->gldv_str_next;
            gld != (gld_t *)&vlan->gldv_str_next; gld = gld->gld_next) {
                if (gld->gld_state != DL_IDLE)
                        continue;       /* not eligible to receive */
                if (gld->gld_flags & GLD_STR_CLOSING)
                        continue;       /* not eligible to receive */

                if (gld->gld_sap == ETHERTYPE_IP) {
                        ip_gld = gld;
                        ipq_candidates++;
                }

                if (gld->gld_sap == ETHERTYPE_IPV6) {
                        ipv6_gld = gld;
                        ipv6q_candidates++;
                }
        }

        if (ipq_candidates == 1) {
                ASSERT(ip_gld != NULL);

                if (ip_gld->gld_flags & GLD_FAST)       /* eligible for ipq */
                        vlan->gldv_ipq = ip_gld->gld_qptr;
        }

        if (ipv6q_candidates == 1) {
                ASSERT(ipv6_gld != NULL);

                if (ipv6_gld->gld_flags & GLD_FAST)     /* eligible for ipq */
                        vlan->gldv_ipv6q = ipv6_gld->gld_qptr;
        }
}

/*
 * gld_flushqueue (q)
 *      used by DLPI primitives that require flushing the queues.
 *      essentially, this is DL_UNBIND_REQ.
 */
static void
gld_flushqueue(queue_t *q)
{
        /* flush all data in both queues */
        /* XXX Should these be FLUSHALL? */
        flushq(q, FLUSHDATA);
        flushq(WR(q), FLUSHDATA);
        /* flush all the queues upstream */
        (void) putctl1(q, M_FLUSH, FLUSHRW);
}

/*
 * gld_devlookup (major)
 * search the device table for the device with specified
 * major number and return a pointer to it if it exists
 */
static glddev_t *
gld_devlookup(int major)
{
        struct glddevice *dev;

        ASSERT(mutex_owned(&gld_device_list.gld_devlock));

        for (dev = gld_device_list.gld_next;
            dev != &gld_device_list;
            dev = dev->gld_next) {
                ASSERT(dev);
                if (dev->gld_major == major)
                        return (dev);
        }
        return (NULL);
}

/*
 * gld_findminor(device)
 * Returns a minor number currently unused by any stream in the current
 * device class (major) list.
 */
static int
gld_findminor(glddev_t *device)
{
        gld_t           *next;
        gld_mac_info_t  *nextmac;
        gld_vlan_t      *nextvlan;
        int             minor;
        int             i;

        ASSERT(mutex_owned(&device->gld_devlock));

        /* The fast way */
        if (device->gld_nextminor >= GLD_MIN_CLONE_MINOR &&
            device->gld_nextminor <= GLD_MAX_CLONE_MINOR)
                return (device->gld_nextminor++);

        /* The steady way */
        for (minor = GLD_MIN_CLONE_MINOR; minor <= GLD_MAX_CLONE_MINOR;
            minor++) {
                /* Search all unattached streams */
                for (next = device->gld_str_next;
                    next != (gld_t *)&device->gld_str_next;
                    next = next->gld_next) {
                        if (minor == next->gld_minor)
                                goto nextminor;
                }
                /* Search all attached streams; we don't need maclock because */
                /* mac stream list is protected by devlock as well as maclock */
                for (nextmac = device->gld_mac_next;
                    nextmac != (gld_mac_info_t *)&device->gld_mac_next;
                    nextmac = nextmac->gldm_next) {
                        gld_mac_pvt_t *pvt =
                            (gld_mac_pvt_t *)nextmac->gldm_mac_pvt;

                        if (!(nextmac->gldm_GLD_flags & GLD_MAC_READY))
                                continue;       /* this one's not ready yet */

                        for (i = 0; i < VLAN_HASHSZ; i++) {
                                for (nextvlan = pvt->vlan_hash[i];
                                    nextvlan != NULL;
                                    nextvlan = nextvlan->gldv_next) {
                                        for (next = nextvlan->gldv_str_next;
                                            next !=
                                            (gld_t *)&nextvlan->gldv_str_next;
                                            next = next->gld_next) {
                                                if (minor == next->gld_minor)
                                                        goto nextminor;
                                        }
                                }
                        }
                }

                return (minor);
nextminor:
                /* don't need to do anything */
                ;
        }
        cmn_err(CE_WARN, "GLD ran out of minor numbers for %s",
            device->gld_name);
        return (0);
}

/*
 * version of insque/remque for use by this driver
 */
struct qelem {
        struct qelem *q_forw;
        struct qelem *q_back;
        /* rest of structure */
};

static void
gldinsque(void *elem, void *pred)
{
        struct qelem *pelem = elem;
        struct qelem *ppred = pred;
        struct qelem *pnext = ppred->q_forw;

        pelem->q_forw = pnext;
        pelem->q_back = ppred;
        ppred->q_forw = pelem;
        pnext->q_back = pelem;
}

static void
gldremque(void *arg)
{
        struct qelem *pelem = arg;
        struct qelem *elem = arg;

        pelem->q_forw->q_back = pelem->q_back;
        pelem->q_back->q_forw = pelem->q_forw;
        elem->q_back = elem->q_forw = NULL;
}

static gld_vlan_t *
gld_add_vlan(gld_mac_info_t *macinfo, uint32_t vid)
{
        gld_mac_pvt_t   *mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        gld_vlan_t      **pp;
        gld_vlan_t      *p;

        pp = &(mac_pvt->vlan_hash[vid % VLAN_HASHSZ]);
        while ((p = *pp) != NULL) {
                ASSERT(p->gldv_id != vid);
                pp = &(p->gldv_next);
        }

        if ((p = kmem_zalloc(sizeof (gld_vlan_t), KM_NOSLEEP)) == NULL)
                return (NULL);

        p->gldv_mac = macinfo;
        p->gldv_id = vid;

        if (vid == VLAN_VID_NONE) {
                p->gldv_ptag = VLAN_VTAG_NONE;
                p->gldv_stats = mac_pvt->statistics;
                p->gldv_kstatp = NULL;
        } else {
                p->gldv_ptag = GLD_MK_PTAG(VLAN_CFI_ETHER, vid);
                p->gldv_stats = kmem_zalloc(sizeof (struct gld_stats),
                    KM_SLEEP);

                if (gld_init_vlan_stats(p) != GLD_SUCCESS) {
                        kmem_free(p->gldv_stats, sizeof (struct gld_stats));
                        kmem_free(p, sizeof (gld_vlan_t));
                        return (NULL);
                }
        }

        p->gldv_str_next = p->gldv_str_prev = (gld_t *)&p->gldv_str_next;
        mac_pvt->nvlan++;
        *pp = p;

        return (p);
}

static void
gld_rem_vlan(gld_vlan_t *vlan)
{
        gld_mac_info_t  *macinfo = vlan->gldv_mac;
        gld_mac_pvt_t   *mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        gld_vlan_t      **pp;
        gld_vlan_t      *p;

        pp = &(mac_pvt->vlan_hash[vlan->gldv_id % VLAN_HASHSZ]);
        while ((p = *pp) != NULL) {
                if (p->gldv_id == vlan->gldv_id)
                        break;
                pp = &(p->gldv_next);
        }
        ASSERT(p != NULL);

        *pp = p->gldv_next;
        mac_pvt->nvlan--;
        if (p->gldv_id != VLAN_VID_NONE) {
                ASSERT(p->gldv_kstatp != NULL);
                kstat_delete(p->gldv_kstatp);
                kmem_free(p->gldv_stats, sizeof (struct gld_stats));
        }
        kmem_free(p, sizeof (gld_vlan_t));
}

gld_vlan_t *
gld_find_vlan(gld_mac_info_t *macinfo, uint32_t vid)
{
        gld_mac_pvt_t   *mac_pvt = (gld_mac_pvt_t *)macinfo->gldm_mac_pvt;
        gld_vlan_t      *p;

        p = mac_pvt->vlan_hash[vid % VLAN_HASHSZ];
        while (p != NULL) {
                if (p->gldv_id == vid)
                        return (p);
                p = p->gldv_next;
        }
        return (NULL);
}

gld_vlan_t *
gld_get_vlan(gld_mac_info_t *macinfo, uint32_t vid)
{
        gld_vlan_t      *vlan;

        if ((vlan = gld_find_vlan(macinfo, vid)) == NULL)
                vlan = gld_add_vlan(macinfo, vid);

        return (vlan);
}

/*
 * gld_bitrevcopy()
 * This is essentially bcopy, with the ability to bit reverse the
 * the source bytes. The MAC addresses bytes as transmitted by FDDI
 * interfaces are bit reversed.
 */
void
gld_bitrevcopy(caddr_t src, caddr_t target, size_t n)
{
        while (n--)
                *target++ = bit_rev[(uchar_t)*src++];
}

/*
 * gld_bitreverse()
 * Convert the bit order by swaping all the bits, using a
 * lookup table.
 */
void
gld_bitreverse(uchar_t *rptr, size_t n)
{
        while (n--) {
                *rptr = bit_rev[*rptr];
                rptr++;
        }
}

char *
gld_macaddr_sprintf(char *etherbuf, unsigned char *ap, int len)
{
        int i;
        char *cp = etherbuf;
        static char digits[] = "0123456789abcdef";

        for (i = 0; i < len; i++) {
                *cp++ = digits[*ap >> 4];
                *cp++ = digits[*ap++ & 0xf];
                *cp++ = ':';
        }
        *--cp = 0;
        return (etherbuf);
}

#ifdef GLD_DEBUG
static void
gld_check_assertions()
{
        glddev_t        *dev;
        gld_mac_info_t  *mac;
        gld_t           *str;
        gld_vlan_t      *vlan;
        int             i;

        mutex_enter(&gld_device_list.gld_devlock);

        for (dev = gld_device_list.gld_next;
            dev != (glddev_t *)&gld_device_list.gld_next;
            dev = dev->gld_next) {
                mutex_enter(&dev->gld_devlock);
                ASSERT(dev->gld_broadcast != NULL);
                for (str = dev->gld_str_next;
                    str != (gld_t *)&dev->gld_str_next;
                    str = str->gld_next) {
                        ASSERT(str->gld_device == dev);
                        ASSERT(str->gld_mac_info == NULL);
                        ASSERT(str->gld_qptr != NULL);
                        ASSERT(str->gld_minor >= GLD_MIN_CLONE_MINOR);
                        ASSERT(str->gld_multicnt == 0);
                        ASSERT(str->gld_mcast == NULL);
                        ASSERT(!(str->gld_flags &
                            (GLD_PROM_PHYS|GLD_PROM_MULT|GLD_PROM_SAP)));
                        ASSERT(str->gld_sap == 0);
                        ASSERT(str->gld_state == DL_UNATTACHED);
                }
                for (mac = dev->gld_mac_next;
                    mac != (gld_mac_info_t *)&dev->gld_mac_next;
                    mac = mac->gldm_next) {
                        int nvlan = 0;
                        gld_mac_pvt_t *pvt = (gld_mac_pvt_t *)mac->gldm_mac_pvt;

                        if (!(mac->gldm_GLD_flags & GLD_MAC_READY))
                                continue;       /* this one's not ready yet */

                        GLDM_LOCK(mac, RW_WRITER);
                        ASSERT(mac->gldm_devinfo != NULL);
                        ASSERT(mac->gldm_mac_pvt != NULL);
                        ASSERT(pvt->interfacep != NULL);
                        ASSERT(pvt->kstatp != NULL);
                        ASSERT(pvt->statistics != NULL);
                        ASSERT(pvt->major_dev == dev);

                        for (i = 0; i < VLAN_HASHSZ; i++) {
                                for (vlan = pvt->vlan_hash[i];
                                    vlan != NULL; vlan = vlan->gldv_next) {
                                        int nstr = 0;

                                        ASSERT(vlan->gldv_mac == mac);

                                        for (str = vlan->gldv_str_next;
                                            str !=
                                            (gld_t *)&vlan->gldv_str_next;
                                            str = str->gld_next) {
                                                ASSERT(str->gld_device == dev);
                                                ASSERT(str->gld_mac_info ==
                                                    mac);
                                                ASSERT(str->gld_qptr != NULL);
                                                ASSERT(str->gld_minor >=
                                                    GLD_MIN_CLONE_MINOR);
                                                ASSERT(
                                                    str->gld_multicnt == 0 ||
                                                    str->gld_mcast);
                                                nstr++;
                                        }
                                        ASSERT(vlan->gldv_nstreams == nstr);
                                        nvlan++;
                                }
                        }
                        ASSERT(pvt->nvlan == nvlan);
                        GLDM_UNLOCK(mac);
                }
                mutex_exit(&dev->gld_devlock);
        }
        mutex_exit(&gld_device_list.gld_devlock);
}
#endif