/*
 * 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 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <sys/types.h>
#include <sys/door.h>
#include <sys/note.h>
#include <sys/drctl.h>
#include <sys/drctl_impl.h>
#include <sys/ddi.h>
#include <sys/sunddi.h>
#include <sys/dr_util.h>

static door_handle_t drctl_dh;  /* Door for upcalls */


int
i_drctl_ioctl(int cmd, intptr_t arg)
{
        int rv;
        drctl_setup_t setup_rqst;

        switch (cmd) {
        case DRCTL_IOCTL_CONNECT_SERVER:
                if (ddi_copyin((caddr_t)arg,
                    &setup_rqst, sizeof (setup_rqst), 0) != 0) {
                        cmn_err(CE_WARN, "i_drctl_ioctl: ddi_copyin failed "
                            "for DRCTL_IOCTL_CONNECT_SERVER");
                        rv = EFAULT;
                        break;
                }

                drctl_dh = door_ki_lookup(setup_rqst.did);
                rv = 0;
                break;

        default:
                rv = EIO;
        }

        return (rv);
}

int
i_drctl_send(void *msg, size_t size, void **obufp, size_t *osize)
{
        int up_err;
        int rv = 0;
        door_arg_t door_args;
        door_handle_t dh = drctl_dh;
        static const char me[] = "i_drctl_send";

retry:
        if (dh)
                door_ki_hold(dh);
        else
                return (EIO);

        door_args.data_ptr = (char *)msg;
        door_args.data_size = size;
        door_args.desc_ptr = NULL;
        door_args.desc_num = 0;

        /*
         * We don't know the size of the message the daemon
         * will pass back to us.  By setting rbuf to NULL,
         * we force the door code to allocate a buf of the
         * appropriate size.  We must set rsize > 0, however,
         * else the door code acts as if no response was
         * expected and doesn't pass the data to us.
         */
        door_args.rbuf = NULL;
        door_args.rsize = 1;
        DR_DBG_CTL("%s: msg %p size %ld obufp %p osize %p\n",
            me, msg, size, (void *)obufp, (void *)osize);

        up_err = door_ki_upcall_limited(dh, &door_args, NULL, SIZE_MAX, 0);
        if (up_err == 0) {
                if (door_args.rbuf == NULL)
                        goto done;

                DR_DBG_CTL("%s: rbuf %p rsize %ld\n", me,
                    (void *)door_args.rbuf, door_args.rsize);

                if (obufp != NULL) {
                        *obufp = door_args.rbuf;
                        *osize = door_args.rsize;
                        DR_DBG_KMEM("%s: (door) alloc addr %p size %ld\n",
                            __func__,
                            (void *)(door_args.rbuf), door_args.rsize);
                } else {
                        /*
                         * No output buffer pointer was passed in,
                         * so the response buffer allocated by the
                         * door code must be deallocated.
                         */
                        DR_DBG_KMEM("%s: free addr %p size %ld\n", __func__,
                            (void *)(door_args.rbuf), door_args.rsize);
                        kmem_free(door_args.rbuf, door_args.rsize);
                }
        } else {
                switch (up_err) {
                case EINTR:
                        DR_DBG_CTL("%s: door call returned EINTR\n", me);
                        /* FALLTHROUGH */
                case EAGAIN:
                        /*
                         * Server process may be forking, try again.
                         */
                        door_ki_rele(dh);
                        delay(hz);
                        goto retry;
                case EBADF:
                case EINVAL:
                        drctl_dh = NULL;
                        DR_DBG_CTL(
                            "%s: door call failed with %d\n", me, up_err);
                        rv = EIO;
                        break;
                default:
                        DR_DBG_CTL("%s: unexpected return "
                            "code %d from door_ki_upcall\n", me, up_err);
                        rv = EIO;
                        break;
                }
        }

done:
        door_ki_rele(dh);
        return (rv);
}