usr/src/cmd/picl/plugins/sun4v/mdesc/init.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 #include <stdio.h>
  30 #include <unistd.h>
  31 #include <stdlib.h>
  32 #include <sys/types.h>
  33 #include <alloca.h>
  34 #include <sys/stat.h>
  35 #include <malloc.h>
  36 #include <fcntl.h>
  37 #include <syslog.h>
  38 #include <mdesc.h>
  39 #include <string.h>
  40 #include <errno.h>
  41
  42 #define MDESC_PATH      "/devices/pseudo/mdesc@0:mdesc"
  43
  44 static void mdesc_free(void *bufp, size_t size);
  45 uint64_t *md_bufp;
  46
  47 md_t *
  48 mdesc_devinit(void)
  49 {
  50         int fd;
  51         md_t *mdp;
  52         size_t size;
  53
  54         /*
  55          * We haven't finished using the previous MD/PRI info.
  56          */
  57         if (md_bufp != NULL)
  58                 return (NULL);
  59
  60         do {
  61                 if ((fd = open(MDESC_PATH, O_RDONLY, 0)) < 0)
  62                         break;
  63
  64                 if (ioctl(fd, MDESCIOCGSZ, &size) < 0)
  65                         break;
  66                 if ((md_bufp = (uint64_t *)malloc(size)) == NULL) {
  67                         (void) close(fd);
  68                         break;
  69                 }
  70
  71                 /*
  72                  * A partial read is as bad as a failed read.
  73                  */
  74                 if (read(fd, md_bufp, size) != size) {
  75                         free(md_bufp);
  76                         md_bufp = NULL;
  77                 }
  78
  79                 (void) close(fd);
  80         /*LINTED: E_CONSTANT_CONDITION */
  81         } while (0);
  82
  83         if (md_bufp) {
  84                 mdp = md_init_intern(md_bufp, malloc, mdesc_free);
  85                 if (mdp == NULL) {
  86                         free(md_bufp);
  87                         md_bufp = NULL;
  88                 }
  89         } else
  90                 mdp = NULL;
  91
  92         return (mdp);
  93 }
  94
  95 /*ARGSUSED*/
  96 void
  97 mdesc_free(void *bufp, size_t size)
  98 {
  99         if (bufp)
 100                 free(bufp);
 101 }
 102
 103 void
 104 mdesc_devfini(md_t *mdp)
 105 {
 106         if (mdp)
 107                 (void) md_fini(mdp);
 108
 109         if (md_bufp)
 110                 free(md_bufp);
 111         md_bufp = NULL;
 112 }