gnu/dist/gdb6/sim/ppc/pk_disklabel.c

   1 /*  This file is part of the program psim.
   2
   3     Copyright (C) 1994-1997, Andrew Cagney <cagney@highland.com.au>
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program; if not, write to the Free Software
  17     Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18
  19     */
  20
  21
  22 #ifndef _PK_DISKLABEL_C_
  23 #define _PK_DISKLABEL_C_
  24
  25 #ifndef STATIC_INLINE_PK_DISKLABEL
  26 #define STATIC_INLINE_PK_DISKLABEL STATIC_INLINE
  27 #endif
  28
  29 #include "device_table.h"
  30
  31 #include "pk.h"
  32
  33 #ifdef HAVE_STDLIB_H
  34 #include <stdlib.h>
  35 #endif
  36
  37
  38
  39 /* PACKAGE
  40
  41    disk-label - all knowing disk I/O package
  42
  43    DESCRIPTION
  44
  45    The disk-label package provides a generic interface to disk
  46    devices.  It uses the arguments specified when an instance is being
  47    created to determine if the raw disk, a partition, or a file within
  48    a partition should be opened.
  49
  50    An instance create call to disk-label could result, for instance,
  51    in the opening of a DOS file system contained within a dos
  52    partition contained within a physical disk.
  53
  54    */
  55
  56 /* taken from bfd/ppcboot.c by Michael Meissner */
  57
  58 /* PPCbug location structure */
  59 typedef struct ppcboot_location {
  60   unsigned8 ind;
  61   unsigned8 head;
  62   unsigned8 sector;
  63   unsigned8 cylinder;
  64 } ppcboot_location_t;
  65
  66 /* PPCbug partition table layout */
  67 typedef struct ppcboot_partition {
  68   ppcboot_location_t partition_begin;   /* partition begin */
  69   ppcboot_location_t partition_end;     /* partition end */
  70   unsigned8 sector_begin[4];            /* 32-bit start RBA (zero-based), little endian */
  71   unsigned8 sector_length[4];           /* 32-bit RBA count (one-based), little endian */
  72 } ppcboot_partition_t;
  73
  74 #if 0
  75 /* PPCbug boot layout.  */
  76 typedef struct ppcboot_hdr {
  77   unsigned8             pc_compatibility[446];  /* x86 instruction field */
  78   ppcboot_partition_t   partition[4];           /* partition information */
  79   unsigned8             signature[2];           /* 0x55 and 0xaa */
  80   unsigned8             entry_offset[4];        /* entry point offset, little endian */
  81   unsigned8             length[4];              /* load image length, little endian */
  82   unsigned8             flags;                  /* flag field */
  83   unsigned8             os_id;                  /* OS_ID */
  84   char                  partition_name[32];     /* partition name */
  85   unsigned8             reserved1[470];         /* reserved */
  86 } ppcboot_hdr_t;
  87 #endif
  88
  89
  90 typedef struct _disklabel {
  91   device_instance *parent;
  92   device_instance *raw_disk;
  93   unsigned_word pos;
  94   unsigned_word sector_begin;
  95   unsigned_word sector_length;
  96 } disklabel;
  97
  98
  99 static unsigned_word
 100 sector2uw(unsigned8 s[4])
 101 {
 102   return ((s[3] << 24)
 103           + (s[2] << 16)
 104           + (s[1] << 8)
 105           + (s[0] << 0));
 106 }
 107
 108
 109 static void
 110 disklabel_delete(device_instance *instance)
 111 {
 112   disklabel *label = device_instance_data(instance);
 113   device_instance_delete(label->raw_disk);
 114   zfree(label);
 115 }
 116
 117
 118 static int
 119 disklabel_read(device_instance *instance,
 120                void *buf,
 121                unsigned_word len)
 122 {
 123   disklabel *label = device_instance_data(instance);
 124   int nr_read;
 125   if (label->pos + len > label->sector_length)
 126     len = label->sector_length - label->pos;
 127   if (device_instance_seek(label->raw_disk, 0,
 128                            label->sector_begin + label->pos) < 0)
 129     return -1;
 130   nr_read = device_instance_read(label->raw_disk, buf, len);
 131   if (nr_read > 0)
 132     label->pos += nr_read;
 133   return nr_read;
 134 }
 135
 136 static int
 137 disklabel_write(device_instance *instance,
 138                 const void *buf,
 139                 unsigned_word len)
 140 {
 141   disklabel *label = device_instance_data(instance);
 142   int nr_written;
 143   if (label->pos + len > label->sector_length)
 144     len = label->sector_length - label->pos;
 145   if (device_instance_seek(label->raw_disk, 0,
 146                            label->sector_begin + label->pos) < 0)
 147     return -1;
 148   nr_written = device_instance_write(label->raw_disk, buf, len);
 149   if (nr_written > 0)
 150     label->pos += nr_written;
 151   return nr_written;
 152 }
 153
 154 static int
 155 disklabel_seek(device_instance *instance,
 156                unsigned_word pos_hi,
 157                unsigned_word pos_lo)
 158 {
 159   disklabel *label = device_instance_data(instance);
 160   if (pos_lo >= label->sector_length || pos_hi != 0)
 161     return -1;
 162   label->pos = pos_lo;
 163   return 0;
 164 }
 165
 166
 167 static const device_instance_callbacks package_disklabel_callbacks = {
 168   disklabel_delete,
 169   disklabel_read,
 170   disklabel_write,
 171   disklabel_seek,
 172 };
 173
 174 /* Reconize different types of boot block */
 175
 176 static int
 177 block0_is_bpb(const unsigned8 block[])
 178 {
 179   const char ebdic_ibma[] = { 0xc9, 0xc2, 0xd4, 0xc1 };
 180   /* ref PowerPC Microprocessor CHRP bindings 1.2b - page 47 */
 181   /* can't start with IBMA */
 182   if (memcmp(block, ebdic_ibma, sizeof(ebdic_ibma)) == 0)
 183     return 0;
 184   /* must have LE 0xAA55 signature at offset 510 */
 185   if (block[511] != 0xAA && block[510] != 0x55)
 186     return 0;
 187   /* valid 16 bit LE bytes per sector - 256, 512, 1024 */
 188   if (block[11] != 0
 189       || (block[12] != 1 && block[12] != 2 && block[12] != 4))
 190     return 0;
 191   /* nr fats is 1 or 2 */
 192   if (block[16] != 1 && block[16] != 2)
 193     return 0;
 194   return 1;
 195 }
 196
 197
 198 /* Verify that the device contains an ISO-9660 File system */
 199
 200 static int
 201 is_iso9660(device_instance *raw_disk)
 202 {
 203   /* ref PowerPC Microprocessor CHRP bindings 1.2b - page 47 */
 204   unsigned8 block[512];
 205   if (device_instance_seek(raw_disk, 0, 512 * 64) < 0)
 206     return 0;
 207   if (device_instance_read(raw_disk, block, sizeof(block)) != sizeof(block))
 208     return 0;
 209   if (block[0] == 0x01
 210       && block[1] == 'C'
 211       && block[2] == 'D'
 212       && block[3] == '0'
 213       && block[4] == '0'
 214       && block[5] == '1')
 215     return 1;
 216   return 0;
 217 }
 218
 219
 220 /* Verify that the disk block contains a valid DOS partition table.
 221    While we're at it have a look around for active partitions etc.
 222
 223    Return 0: invalid
 224    Return 1..4: valid, value returned is the first active partition
 225    Return -1: no active partition */
 226
 227 static int
 228 block0_is_fdisk(const unsigned8 block[])
 229 {
 230   const int partition_type_fields[] = { 0, 0x1c2, 0x1d2, 0x1e2, 0x1f2 };
 231   const int partition_active_fields[] = { 0, 0x1be, 0x1ce, 0x1de, 0xee };
 232   int partition;
 233   int active = -1;
 234   /* ref PowerPC Microprocessor CHRP bindings 1.2b - page 47 */
 235   /* must have LE 0xAA55 signature at offset 510 */
 236   if (block[511/*0x1ff*/] != 0xAA && block[510/*0x1fe*/] != 0x55)
 237     return 0;
 238   /* must contain valid partition types */
 239   for (partition = 1; partition <= 4 && active != 0; partition++) {
 240     int partition_type = block[partition_type_fields[partition]];
 241     int is_active = block[partition_active_fields[partition]] == 0x80;
 242     const char *type;
 243     switch (partition_type) {
 244     case 0x00:
 245       type = "UNUSED";
 246       break;
 247     case 0x01:
 248       type = "FAT 12 File system";
 249       break;
 250     case 0x04:
 251       type = "FAT 16 File system";
 252       break;
 253     case 0x05:
 254     case 0x06:
 255       type = "rejected - extended/chained partition not supported";
 256       active = 0;
 257       break;
 258     case 0x41:
 259       type = "Single program image";
 260       break;
 261     case 0x82:
 262       type = "Solaris?";
 263       break;
 264     case 0x96:
 265       type = "ISO 9660 File system";
 266       break;
 267     default:
 268       type = "rejected - unknown type";
 269       active = 0;
 270       break;
 271     }
 272     PTRACE(disklabel, ("partition %d of type 0x%02x - %s%s\n",
 273                        partition,
 274                        partition_type,
 275                        type,
 276                        is_active && active != 0 ? " (active)" : ""));
 277     if (partition_type != 0 && is_active && active < 0)
 278       active = partition;
 279   }
 280   return active;
 281 }
 282
 283
 284 /* Verify that block0 corresponds to a MAC disk */
 285
 286 static int
 287 block0_is_mac_disk(const unsigned8 block[])
 288 {
 289   /* ref PowerPC Microprocessor CHRP bindings 1.2b - page 47 */
 290   /* signature - BEx4552 at offset 0 */
 291   if (block[0] != 0x45 || block[1] != 0x52)
 292     return 0;
 293   return 1;
 294 }
 295
 296
 297 /* Open a logical disk/file */
 298
 299 device_instance *
 300 pk_disklabel_create_instance(device_instance *raw_disk,
 301                              const char *args)
 302 {
 303   int partition;
 304   char *filename;
 305
 306   /* parse the arguments */
 307   if (args == NULL) {
 308     partition = 0;
 309     filename = NULL;
 310   }
 311   else {
 312     partition = strtoul((char*)args, &filename, 0);
 313     if (filename == args)
 314       partition = -1; /* not specified */
 315     if (*filename == ',')
 316       filename++;
 317     if (*filename == '\0')
 318       filename = NULL; /* easier */
 319   }
 320
 321   if (partition == 0) {
 322     /* select the raw disk */
 323     return raw_disk;
 324   }
 325   else {
 326     unsigned8 boot_block[512];
 327     /* get the boot block for examination */
 328     if (device_instance_seek(raw_disk, 0, 0) < 0)
 329       device_error(device_instance_device(raw_disk),
 330                    "Problem seeking on raw disk");
 331     if (device_instance_read(raw_disk, &boot_block, sizeof(boot_block))
 332         != sizeof(boot_block))
 333       device_error(device_instance_device(raw_disk), "Problem reading boot block");
 334
 335     if (partition < 0) {
 336       /* select the active partition */
 337       if (block0_is_bpb(boot_block)) {
 338         device_error(device_instance_device(raw_disk), "Unimplemented active BPB");
 339       }
 340       else if (block0_is_fdisk(boot_block)) {
 341         int active = block0_is_fdisk(boot_block);
 342         device_error(device_instance_device(raw_disk), "Unimplemented active FDISK (%d)",
 343                      active);
 344       }
 345       else if (is_iso9660(raw_disk)) {
 346         device_error(device_instance_device(raw_disk), "Unimplemented active ISO9660");
 347       }
 348       else if (block0_is_mac_disk(boot_block)) {
 349         device_error(device_instance_device(raw_disk), "Unimplemented active MAC DISK");
 350       }
 351       else {
 352         device_error(device_instance_device(raw_disk), "Unreconized bootblock");
 353       }
 354     }
 355     else {
 356       /* select the specified disk partition */
 357       if (block0_is_bpb(boot_block)) {
 358         device_error(device_instance_device(raw_disk), "Unimplemented BPB");
 359       }
 360       else if (block0_is_fdisk(boot_block)) {
 361         /* return an instance */
 362         ppcboot_partition_t *partition_table = (ppcboot_partition_t*) &boot_block[446];
 363         ppcboot_partition_t *partition_entry;
 364         disklabel *label;
 365         if (partition > 4)
 366           device_error(device_instance_device(raw_disk),
 367                        "Only FDISK partitions 1..4 supported");
 368         partition_entry = &partition_table[partition - 1];
 369         label = ZALLOC(disklabel);
 370         label->raw_disk = raw_disk;
 371         label->pos = 0;
 372         label->sector_begin = 512 * sector2uw(partition_entry->sector_begin);
 373         label->sector_length = 512 * sector2uw(partition_entry->sector_length);
 374         PTRACE(disklabel, ("partition %ld, sector-begin %ld, length %ld\n",
 375                            (long)partition,
 376                            (long)label->sector_begin,
 377                            (long)label->sector_length));
 378         if (filename != NULL)
 379           device_error(device_instance_device(raw_disk),
 380                        "FDISK file names not yet supported");
 381         return device_create_instance_from(NULL, raw_disk,
 382                                            label,
 383                                            NULL, args,
 384                                            &package_disklabel_callbacks);
 385       }
 386       else if (block0_is_mac_disk(boot_block)) {
 387         device_error(device_instance_device(raw_disk), "Unimplemented MAC DISK");
 388       }
 389       else {
 390         device_error(device_instance_device(raw_disk),
 391                      "Unreconized bootblock");
 392       }
 393     }
 394   }
 395
 396   return NULL;
 397 }
 398
 399
 400 #endif /* _PK_DISKLABEL_C_ */
 401