sys/arch/cobalt/stand/boot/devopen.c

   1 /*      $NetBSD: devopen.c,v 1.6 2008/04/28 20:23:16 martin Exp $       */
   2
   3 /*-
   4  * Copyright (c) 2003 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software contributed to The NetBSD Foundation
   8  * by Rolf Grossmann.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 #include <lib/libsa/stand.h>
  33 #include <lib/libkern/libkern.h>
  34
  35 #include "boot.h"
  36
  37 extern const struct fs_ops file_system_nfs;
  38
  39 /*
  40  * Parse a device spec.
  41  *
  42  * Format:
  43  *  [device:][filename]
  44  */
  45 int
  46 devparse(const char *fname, int *dev, uint8_t *unit, uint8_t *part,
  47     const char **file)
  48 {
  49         const char *col;
  50
  51         *unit = 0;      /* default to wd0a */
  52         *part = 0;
  53         *dev  = 0;
  54         *file = DEFKERNELNAME;
  55
  56         if (fname == NULL)
  57                 return 0;
  58
  59         if ((col = strchr(fname, ':')) != NULL) {
  60                 int devlen;
  61                 uint8_t i, u, p;
  62                 struct devsw *dp;
  63                 char devname[MAXDEVNAME];
  64
  65                 devlen = col - fname;
  66                 if (devlen > MAXDEVNAME)
  67                         return EINVAL;
  68
  69 #define isnum(c)        (((c) >= '0') && ((c) <= '9'))
  70 #define isalpha(c)      (((c) >= 'a') && ((c) <= 'z'))
  71
  72                 /* extract device name */
  73                 for (i = 0; isalpha(fname[i]) && (i < devlen); i++)
  74                         devname[i] = fname[i];
  75                 devname[i] = '\0';
  76
  77                 if (strcmp(devname, "nfs") == 0) {
  78                         /* no unit number or partition suffix on netboot */
  79                         u = 0;
  80                         p = 0;
  81                         nfsys = 1;
  82                         file_system[0] = file_system_nfs;
  83                 } else {
  84                         /* parse [disk][unit][part] (ex. wd0a) strings */
  85                         if (!isnum(fname[i]))
  86                                 return EUNIT;
  87
  88                         /* device number */
  89                         for (u = 0; isnum(fname[i]) && (i < devlen); i++)
  90                                 u = u * 10 + (fname[i] - '0');
  91
  92                         if (!isalpha(fname[i]))
  93                                 return EPART;
  94
  95                         /* partition number */
  96                         p = 0;
  97                         if (i < devlen)
  98                                 p = fname[i++] - 'a';
  99
 100                         if (i != devlen)
 101                                 return ENXIO;
 102                 }
 103
 104                 /* check device name */
 105                 for (dp = devsw, i = 0; i < ndevs; dp++, i++) {
 106                         if (dp->dv_name && !strcmp(devname, dp->dv_name))
 107                                 break;
 108                 }
 109
 110                 if (i >= ndevs)
 111                         return ENXIO;
 112
 113                 *unit = u;
 114                 *part = p;
 115                 *dev  = i;
 116                 fname = ++col;
 117         }
 118
 119         if (*fname)
 120                 *file = fname;
 121
 122         return 0;
 123 }
 124
 125 int
 126 devopen(struct open_file *f, const char *fname, char **file)
 127 {
 128         struct devsw *dp;
 129         uint8_t unit, part;
 130         int dev, error;
 131
 132         DPRINTF(("devopen(%s)\n", fname));
 133
 134         if ((error = devparse(fname, &dev, &unit, &part,
 135             (const char **)file)) != 0)
 136                 return error;
 137
 138         dp = &devsw[dev];
 139         if ((void *)dp->dv_open == (void *)nodev)
 140                 return ENXIO;
 141
 142         f->f_dev = dp;
 143
 144         if ((error = (*dp->dv_open)(f, unit, part)) != 0)
 145         printf("%s%d%c: %d = %s\n", devsw[dev].dv_name,
 146             unit, 'a' + part, error, strerror(error));
 147
 148         return error;
 149 }