sys/arch/atari/stand/libsa/diskio.c

   1 /*      $NetBSD: diskio.c,v 1.7 2009/03/14 21:04:07 dsl Exp $   */
   2
   3 /*
   4  * Copyright (c) 1995 Waldi Ravens.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *        This product includes software developed by Waldi Ravens.
  18  * 4. The name of the author may not be used to endorse or promote products
  19  *    derived from this software without specific prior written permission
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31  */
  32
  33 #include <lib/libsa/stand.h>
  34 #include "atari_stand.h"
  35 #include <sys/disklabel.h>
  36
  37 typedef int (*rdsec_f)(void *buffer, u_int offset, u_int count);
  38 typedef struct { rdsec_f rds; u_int rst; u_int rend; } bdevd_t;
  39
  40 static int rootstrategy(void *, int, daddr_t, size_t, void *, size_t *);
  41 static int rootopen(struct open_file *, ...);
  42 static int rootclose(struct open_file *);
  43 static int rootioctl(struct open_file *, u_long, void *);
  44
  45 struct devsw devsw[] = {
  46         { "root", rootstrategy, rootopen, rootclose, rootioctl }
  47 };
  48 static bdevd_t  bootdev;
  49
  50 /*
  51  * Initialise boot device info.
  52  */
  53 int
  54 init_dskio (void *func, void *label, int root)
  55 {
  56         struct disklabel *dl = label;
  57         struct partition *pd = &dl->d_partitions[root];
  58
  59         if (dl->d_magic != DISKMAGIC || dl->d_magic2 != DISKMAGIC
  60             || dl->d_npartitions > MAXPARTITIONS || dkcksum(dl) != 0) {
  61                 printf("Invalid disk label.\n");
  62                 return(-1);
  63         }
  64         if (root >= 0) {
  65                 if (root >= dl->d_npartitions
  66                     || pd->p_fstype != FS_BSDFFS || pd->p_size == 0) {
  67                         printf("No suitable root.\n");
  68                         return(-1);
  69                 }
  70                 bootdev.rds  = func;
  71                 bootdev.rst  = pd->p_offset;
  72                 bootdev.rend = pd->p_offset + pd->p_size - 1;
  73         }
  74         return(0);
  75 }
  76
  77 /*
  78  * No choice, the kernel is loaded from the
  79  * same device as the bootstrap.
  80  */
  81 int
  82 devopen (struct open_file *f, const char *fname, char **file)
  83 {
  84         f->f_devdata = &bootdev;
  85         f->f_dev = &devsw[0];
  86         *file = (char *)fname;
  87         return(0);
  88 }
  89
  90 static int
  91 rootstrategy (void *devd, int flag, daddr_t dblk, size_t size, void *buf, size_t *rsize)
  92 {
  93         bdevd_t *dd = devd;
  94         daddr_t stb = dd->rst + dblk;
  95         size_t  nb  = size >> 9;
  96
  97         if ((flag == F_READ) && !(size & 511) && (stb + nb <= dd->rend)) {
  98                 if (!dd->rds(buf, stb, nb)) {
  99                         *rsize = size;
 100                         return(0);
 101                 }
 102         }
 103         *rsize = 0;
 104         return(EIO);
 105 }
 106
 107 static int
 108 rootopen (struct open_file *f, ...)
 109 {
 110         return(0);
 111 }
 112
 113 static int
 114 rootclose (struct open_file *f)
 115 {
 116         return(EIO);
 117 }
 118
 119 static int
 120 rootioctl (struct open_file *f, u_long cmd, void *data)
 121 {
 122         return(EIO);
 123 }