io/dld/dld_drv.c

	dld_drv.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

/*
 * Data-Link Driver
 */

#include    <sys/types.h>
#include    <sys/stream.h>
#include    <sys/conf.h>
#include    <sys/stat.h>
#include    <sys/ddi.h>
#include    <sys/sunddi.h>
#include    <sys/dlpi.h>
#include    <sys/modctl.h>
#include    <sys/kmem.h>
#include    <inet/common.h>

#include    <sys/dls.h>
#include    <sys/dld.h>
#include    <sys/dld_impl.h>

static void drv_init(void);
static int  drv_fini(void);

static int  drv_getinfo(dev_info_t  *, ddi_info_cmd_t, void *, void **);
static int  drv_attach(dev_info_t *, ddi_attach_cmd_t);
static int  drv_detach(dev_info_t *, ddi_detach_cmd_t);

static int  drv_open(queue_t *, dev_t *, int, int, cred_t *);
static int  drv_close(queue_t *);

static void drv_uw_put(queue_t *, mblk_t *);
static void drv_uw_srv(queue_t *);

dev_info_t  *dld_dip;       /* dev_info_t for the driver */
uint32_t    dld_opt;        /* Global options */
boolean_t   dld_open;       /* Flag to note that the control */
                    /* node is open */
boolean_t   dld_aul = B_TRUE;   /* Set to B_FALSE to prevent driver */
                    /* unloading */

static kmutex_t drv_lock;       /* Needs no initialization */

static  struct  module_info drv_info = {
    0,          /* mi_idnum */
    DLD_DRIVER_NAME,    /* mi_idname */
    0,          /* mi_minpsz */
    (64 * 1024),        /* mi_maxpsz */
    1,          /* mi_hiwat */
    0           /* mi_lowat */
};

static  struct qinit        drv_ur_init = {
    NULL,           /* qi_putp */
    NULL,           /* qi_srvp */
    drv_open,       /* qi_qopen */
    drv_close,      /* qi_qclose */
    NULL,           /* qi_qadmin */
    &drv_info,      /* qi_minfo */
    NULL            /* qi_mstat */
};

static  struct qinit        drv_uw_init = {
    (pfi_t)drv_uw_put,  /* qi_putp */
    (pfi_t)drv_uw_srv,  /* qi_srvp */
    NULL,           /* qi_qopen */
    NULL,           /* qi_qclose */
    NULL,           /* qi_qadmin */
    &drv_info,      /* qi_minfo */
    NULL            /* qi_mstat */
};

static  struct streamtab    drv_stream = {
    &drv_ur_init,       /* st_rdinit */
    &drv_uw_init,       /* st_wrinit */
    NULL,           /* st_muxrinit */
    NULL            /* st_muxwinit */
};

DDI_DEFINE_STREAM_OPS(drv_ops, nulldev, nulldev, drv_attach, drv_detach,
    nodev, drv_getinfo, D_MP | D_MTQPAIR | D_MTPUTSHARED, &drv_stream);

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

extern  struct mod_ops      mod_driverops;

static  struct modldrv      drv_modldrv = {
    &mod_driverops,
    DLD_INFO,
    &drv_ops
};

static  struct modlinkage   drv_modlinkage = {
    MODREV_1,
    &drv_modldrv,
    NULL
};

int
_init(void)
{
    int err;

    if ((err = mod_install(&drv_modlinkage)) != 0)
        return (err);

#ifdef  DEBUG
    cmn_err(CE_NOTE, "!%s loaded", DLD_INFO);
#endif  /* DEBUG */

    return (0);
}

int
_fini(void)
{
    int err;

    if (!dld_aul)
        return (ENOTSUP);

    if ((err = mod_remove(&drv_modlinkage)) != 0)
        return (err);

#ifdef  DEBUG
    cmn_err(CE_NOTE, "!%s unloaded", DLD_INFO);
#endif  /* DEBUG */

    return (err);
}

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


/*
 * Initialize compoment modules.
 */
static void
drv_init(void)
{
    dld_minor_init();
    dld_node_init();
    dld_str_init();
    dld_ppa_init();
}

static int
drv_fini(void)
{
    int err;

    if ((err = dld_ppa_fini()) != 0)
        return (err);

    err = dld_str_fini();
    ASSERT(err == 0);

    err = dld_node_fini();
    ASSERT(err == 0);

    err = dld_minor_fini();
    ASSERT(err == 0);

    return (0);
}

/*
 * devo_getinfo: getinfo(9e)
 */
/*ARGSUSED*/
static int
drv_getinfo(dev_info_t *dip, ddi_info_cmd_t cmd, void *arg, void **resp)
{
    if (dld_dip == NULL)
        return (DDI_FAILURE);

    switch (cmd) {
    case DDI_INFO_DEVT2INSTANCE:
        *resp = (void *)0;
        break;
    case DDI_INFO_DEVT2DEVINFO:
        *resp = (void *)dld_dip;
        break;
    default:
        return (DDI_FAILURE);
    }

    return (DDI_SUCCESS);
}

/*
 * Check properties to set options. (See dld.h for property definitions).
 */
static void
drv_set_opt(dev_info_t *dip)
{
    if (ddi_prop_get_int(DDI_DEV_T_ANY, dip, DDI_PROP_DONTPASS,
        DLD_PROP_NO_STYLE1, 0) != 0) {
#ifdef  DEBUG
        cmn_err(CE_NOTE, "%s: ON", DLD_PROP_NO_STYLE1);
#endif  /* DEBUG */
        dld_opt |= DLD_OPT_NO_STYLE1;
    }

    if (ddi_prop_get_int(DDI_DEV_T_ANY, dip, DDI_PROP_DONTPASS,
        DLD_PROP_NO_FASTPATH, 0) != 0) {
#ifdef  DEBUG
        cmn_err(CE_NOTE, "%s: ON", DLD_PROP_NO_FASTPATH);
#endif  /* DEBUG */
        dld_opt |= DLD_OPT_NO_FASTPATH;
    }

    if (ddi_prop_get_int(DDI_DEV_T_ANY, dip, DDI_PROP_DONTPASS,
        DLD_PROP_NO_POLL, 0) != 0) {
#ifdef  DEBUG
        cmn_err(CE_NOTE, "%s: ON", DLD_PROP_NO_POLL);
#endif  /* DEBUG */
        dld_opt |= DLD_OPT_NO_POLL;
    }

    if (ddi_prop_get_int(DDI_DEV_T_ANY, dip, DDI_PROP_DONTPASS,
        DLD_PROP_NO_ZEROCOPY, 0) != 0) {
#ifdef  DEBUG
        cmn_err(CE_NOTE, "%s: ON", DLD_PROP_NO_ZEROCOPY);
#endif  /* DEBUG */
        dld_opt |= DLD_OPT_NO_ZEROCOPY;
    }
}

/*
 * devo_attach: attach(9e)
 */
static int
drv_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
{
    if (cmd != DDI_ATTACH)
        return (DDI_FAILURE);

    ASSERT(ddi_get_instance(dip) == 0);

    drv_init();
    drv_set_opt(dip);

    /*
     * Create control node. DLPI provider nodes will be created on demand.
     */
    if (ddi_create_minor_node(dip, DLD_CONTROL_MINOR_NAME, S_IFCHR,
        DLD_CONTROL_MINOR, DDI_PSEUDO, 0) != DDI_SUCCESS)
        return (DDI_FAILURE);

    dld_dip = dip;

    /*
     * Log the fact that the driver is now attached.
     */
    ddi_report_dev(dip);
    return (DDI_SUCCESS);
}

/*
 * devo_detach: detach(9e)
 */
static int
drv_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
{
    if (cmd != DDI_DETACH)
        return (DDI_FAILURE);

    if (drv_fini() != 0)
        return (DDI_FAILURE);

    ASSERT(dld_dip == dip);

    /*
     * Remove the control node.
     */
    ddi_remove_minor_node(dip, DLD_CONTROL_MINOR_NAME);
    dld_dip = NULL;

    return (DDI_SUCCESS);
}

/*
 * qi_qopen: open(9e)
 */
/*ARGSUSED*/
static int
drv_open(queue_t *rq, dev_t *devp, int flag, int sflag, cred_t *credp)
{
    dld_str_t   *dsp;
    dld_node_t  *dnp;
    dld_ppa_t   *dpp;
    minor_t     minor;
    int     err;

    ASSERT(sflag != MODOPEN);

    /*
     * This is a cloning driver and therefore each queue should only
     * ever get opened once.
     */
    ASSERT(rq->q_ptr == NULL);
    if (rq->q_ptr != NULL)
        return (EBUSY);

    /*
     * Grab the minor number of the dev_t that was opened. Because this
     * is a cloning driver this will be distinct from the actual minor
     * of the dev_t handed back.
     */
    minor = getminor(*devp);

    /*
     * Create a new dld_str_t for the stream. This will grab a new minor
     * number that will be handed back in the cloned dev_t.
     */
    dsp = dld_str_create(rq);

    if (minor != DLD_CONTROL_MINOR) {
        /*
         * This is not the control node, so look up the DLPI
         * provider node that is being opened.
         */
        if ((dnp = dld_node_find(minor)) == NULL) {
            err = ENODEV;
            goto failed;
        }

        dsp->ds_dnp = dnp;
        dsp->ds_type = DLD_DLPI;

        ASSERT(dsp->ds_dlstate == DL_UNATTACHED);
        if (dnp->dn_style == DL_STYLE1) {
            /*
             * This is a style 1 provider node so we have a
             * non-ambiguous PPA.
             */
            dpp = dld_node_ppa_find(dnp, -1);

            if ((err = dld_str_attach(dsp, dpp)) != 0)
                goto failed;
            dsp->ds_dlstate = DL_UNBOUND;
        }
    } else {
        /*
         * This is the control node. It is exclusive-access so
         * verify that it is not already open.
         */
        mutex_enter(&drv_lock);
        if (dld_open) {
            err = EBUSY;
            mutex_exit(&drv_lock);
            goto failed;
        }

        dld_open = B_TRUE;
        mutex_exit(&drv_lock);

        dsp->ds_type = DLD_CONTROL;
    }

    /*
     * Enable the queue srv(9e) routine.
     */
    qprocson(rq);

    /*
     * Construct a cloned dev_t to hand back.
     */
    *devp = makedevice(getmajor(*devp), dsp->ds_minor);
    return (0);

failed:
    dld_str_destroy(dsp);
    return (err);
}

/*
 * qi_qclose: close(9e)
 */
static int
drv_close(queue_t *rq)
{
    dld_str_t   *dsp;

    dsp = rq->q_ptr;
    ASSERT(dsp != NULL);

    /*
     * Disable the queue srv(9e) routine.
     */
    qprocsoff(rq);

    if (dsp->ds_type != DLD_CONTROL) {
        /*
         * This stream was open to a provider node. Check to see
         * if it has been cleanly shut down.
         */
        if (dsp->ds_dlstate != DL_UNATTACHED) {
            /*
             * The stream is either open to a style 1 provider or
             * this is not clean shutdown. Detach from the PPA.
             * (This is still ok even in the style 1 case).
             */
            dld_str_detach(dsp);
            dsp->ds_dlstate = DL_UNATTACHED;
        }
    } else {
        /*
         * This stream was open to the control node. Clear the flag
         * to allow another stream access.
         */
        ASSERT(dld_open);
        dld_open = B_FALSE;
    }

    dld_str_destroy(dsp);
    return (0);
}

/*
 * qi_qputp: put(9e)
 */
static void
drv_uw_put(queue_t *wq, mblk_t *mp)
{
    dld_str_t   *dsp;

    dsp = wq->q_ptr;
    ASSERT(dsp != NULL);

    /*
     * Call the put(9e) processor.
     */
    dld_str_put(dsp, mp);
}

/*
 * qi_srvp: srv(9e)
 */
static void
drv_uw_srv(queue_t *wq)
{
    mblk_t      *mp = NULL;
    mblk_t      *p;
    mblk_t      **pp;
    dld_str_t   *dsp;

    dsp = wq->q_ptr;
    ASSERT(dsp != NULL);

    /*
     * Loop round and pull a chain of messages from the queue.
     */
    for (pp = &mp; (p = getq(wq)) != NULL; pp = &(p->b_next))
        *pp = p;

    /*
     * If there was nothing on the queue then there's nothing to do.
     */
    if (mp == NULL)
        return;

    /*
     * Call the srv(9e) processor.
     */
    dld_str_srv(dsp, mp);
}