/*
 * 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);
        }
}