common/ktli/t_kopen.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 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*  Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*    All Rights Reserved   */

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

/*
 * Kernel TLI-like function to initialize a transport
 * endpoint using the protocol specified.
 *
 * Returns:
 *  0 on success and "tiptr" is set to a valid transport pointer,
 *  else a positive error code.
 */

#include <sys/param.h>
#include <sys/types.h>
#include <sys/proc.h>
#include <sys/file.h>
#include <sys/user.h>
#include <sys/vnode.h>
#include <sys/errno.h>
#include <sys/stream.h>
#include <sys/ioctl.h>
#include <sys/stropts.h>
#include <sys/strsubr.h>
#include <sys/tihdr.h>
#include <sys/timod.h>
#include <sys/tiuser.h>
#include <sys/t_kuser.h>
#include <sys/kmem.h>
#include <sys/cmn_err.h>

static t_scalar_t _t_setsize(t_scalar_t);

int
t_kopen(file_t *fp, dev_t rdev, int flags, TIUSER **tiptr, cred_t *cr)
{
    int         madefp = 0;
    struct T_info_ack   inforeq;
    int         retval;
    vnode_t         *vp;
    struct strioctl     strioc;
    int         error;
    TIUSER          *ntiptr;
    int         rtries = 0;

    /*
     * Special case for install: miniroot needs to be able to access files
     * via NFS as though it were always in the global zone.
     */
    if (nfs_global_client_only != 0)
        cr = kcred;

    KTLILOG(2, "t_kopen: fp %x, ", fp);
    KTLILOG(2, "rdev %x, ", rdev);
    KTLILOG(2, "flags %x\n", flags);

    *tiptr = NULL;
    error = 0;
    retval = 0;
    if (fp == NULL) {
        if (rdev == NODEV) {
            KTLILOG(1, "t_kopen: null device\n", 0);
            return (EINVAL);
        }

        /*
         * allocate a file pointer, but
         * no file descripter.
         */
        if ((error = falloc(NULL, flags, &fp, NULL)) != 0) {
            KTLILOG(1, "t_kopen: falloc: %d\n", error);
            return (error);
        }

        /* Install proper cred in file */
        if (cr != fp->f_cred) {
            crhold(cr);
            crfree(fp->f_cred);
            fp->f_cred = cr;
        }

        vp = makespecvp(rdev, VCHR);

        /*
         * this will call the streams open for us.
         * Want to retry if error is EAGAIN, the streams open routine
         * might fail due to temporarely out of memory.
         */
        do {
            if ((error = VOP_OPEN(&vp, flags, cr, NULL))
                == EAGAIN) {
                (void) delay(hz);
            }
        } while (error == EAGAIN && ++rtries < 5);

        if (error) {
            KTLILOG(1, "t_kopen: VOP_OPEN: %d\n", error);
            unfalloc(fp);
            VN_RELE(vp);
            return (error);
        }
        /*
         * fp is completely initialized so drop the write lock.
         * I actually don't need any locking on fp in here since
         * there is no fd pointing at it.  However, since I could
         * call closef if there is an error and closef requires
         * the fp read locked, I will acquire the read lock here
         * and make sure I release it before I leave this routine.
         */
        fp->f_vnode = vp;
        mutex_exit(&fp->f_tlock);

        madefp = 1;
    } else {
        vp = fp->f_vnode;
    }

    if (vp->v_stream == NULL) {
        if (madefp)
            (void) closef(fp);
        KTLILOG(1, "t_kopen: not a streams device\n", 0);
        return (ENOSTR);
    }

    /*
     * allocate a new transport structure
     */
    ntiptr = kmem_alloc(TIUSERSZ, KM_SLEEP);
    ntiptr->fp = fp;
    ntiptr->flags = madefp ? MADE_FP : 0;

    KTLILOG(2, "t_kopen: vp %x, ", vp);
    KTLILOG(2, "stp %x\n", vp->v_stream);

    /*
     * see if TIMOD is already pushed
     */
    error = strioctl(vp, I_FIND, (intptr_t)"timod", 0, K_TO_K, cr, &retval);
    if (error) {
        kmem_free(ntiptr, TIUSERSZ);
        if (madefp)
            (void) closef(fp);
        KTLILOG(1, "t_kopen: strioctl(I_FIND, timod): %d\n", error);
        return (error);
    }

    if (retval == 0) {
tryagain:
        error = strioctl(vp, I_PUSH, (intptr_t)"timod", 0, K_TO_K, cr,
            &retval);
        if (error) {
            switch (error) {
            case ENOSPC:
            case EAGAIN:
            case ENOSR:
                /*
                 * This probably means the master file
                 * should be tuned.
                 */
                cmn_err(CE_WARN,
                "t_kopen: I_PUSH of timod failed, error %d\n",
                    error);
                (void) delay(hz);
                error = 0;
                goto tryagain;

            default:
                kmem_free(ntiptr, TIUSERSZ);
                if (madefp)
                    (void) closef(fp);
                KTLILOG(1, "t_kopen: I_PUSH (timod): %d",
                    error);
                return (error);
            }
        }
    }

    inforeq.PRIM_type = T_INFO_REQ;
    strioc.ic_cmd = TI_GETINFO;
    strioc.ic_timout = 0;
    strioc.ic_dp = (char *)&inforeq;
    strioc.ic_len = (int)sizeof (struct T_info_req);

    error = strdoioctl(vp->v_stream, &strioc, FNATIVE, K_TO_K, cr, &retval);
    if (error) {
        kmem_free(ntiptr, TIUSERSZ);
        if (madefp)
            (void) closef(fp);
        KTLILOG(1, "t_kopen: strdoioctl(T_INFO_REQ): %d\n", error);
        return (error);
    }

    if (retval) {
        if ((retval & 0xff) == TSYSERR)
            error = (retval >> 8) & 0xff;
        else
            error = t_tlitosyserr(retval & 0xff);
        kmem_free(ntiptr, TIUSERSZ);
        if (madefp)
            (void) closef(fp);
        KTLILOG(1, "t_kopen: strdoioctl(T_INFO_REQ): retval: 0x%x\n",
            retval);
        return (error);
    }

    if (strioc.ic_len != sizeof (struct T_info_ack)) {
        kmem_free(ntiptr, TIUSERSZ);
        if (madefp)
            (void) closef(fp);
        KTLILOG(1,
        "t_kopen: strioc.ic_len != sizeof (struct T_info_ack): %d\n",
            strioc.ic_len);
        return (EPROTO);
    }

    ntiptr->tp_info.addr = _t_setsize(inforeq.ADDR_size);
    ntiptr->tp_info.options = _t_setsize(inforeq.OPT_size);
    ntiptr->tp_info.tsdu = _t_setsize(inforeq.TSDU_size);
    ntiptr->tp_info.etsdu = _t_setsize(inforeq.ETSDU_size);
    ntiptr->tp_info.connect = _t_setsize(inforeq.CDATA_size);
    ntiptr->tp_info.discon = _t_setsize(inforeq.DDATA_size);
    ntiptr->tp_info.servtype = inforeq.SERV_type;

    *tiptr = ntiptr;

    return (0);
}

#define DEFSIZE 128

static t_scalar_t
_t_setsize(t_scalar_t infosize)
{
    switch (infosize) {
    case -1:
        return (DEFSIZE);
    case -2:
        return (0);
    default:
        return (infosize);
    }
}