sun4v/mdesc/init.c

	init.c revision 1ae0874509b6811fdde1dfd46f0d93fd09867a3f
/*
 * 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 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

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

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <alloca.h>
#include <sys/stat.h>
#include <malloc.h>
#include <fcntl.h>
#include <syslog.h>
#include <mdesc.h>
#include <string.h>
#include <errno.h>

#define MDESC_PATH  "/devices/pseudo/mdesc@0:mdesc"
#define SIZE    8192

static void mdesc_free(void *bufp, size_t size);
uint8_t *md_bufp;

md_t *
mdesc_devinit(void)
{
    int fh;
    int res;
    int size;
    int offset;
    md_t *mdp;

    if (md_bufp != NULL)
        return (NULL);

    fh = open(MDESC_PATH, O_RDONLY, 0);
    if (fh < 0) {
        return (NULL);
    }

    size = SIZE;    /* initial size */
    offset = 0;

    md_bufp = malloc(size);
    if (NULL == md_bufp) {
        return (NULL);
    }

        /* OK read until we get a EOF */

    do {
        int len;

        len = size - offset;

        while (len < SIZE) {
            size += SIZE;
            md_bufp = realloc(md_bufp, size);
            if (NULL == md_bufp)
                return (NULL);
            len = size - offset;
        }

        do {
            res = read(fh, md_bufp + offset, len);
        } while ((res < 0) && (errno == EAGAIN));

        if (res < 0) {
            free(md_bufp);
            return (NULL);
        }

        offset += res;
    } while (res > 0);

    (void) close(fh);

    md_bufp = realloc(md_bufp, offset);
    if (NULL == md_bufp)
        return (NULL);

    mdp = md_init_intern((uint64_t *)md_bufp, malloc, mdesc_free);
    if (NULL == mdp) {
        free(md_bufp);
        return (NULL);
    }

    return (mdp);
}

/*ARGSUSED*/
void
mdesc_free(void *bufp, size_t size)
{
    if (bufp)
        free(bufp);
}

void
mdesc_devfini(md_t *mdp)
{
    if (mdp)
        (void) md_fini(mdp);

    if (md_bufp)
        free(md_bufp);
    md_bufp = NULL;
}