linux-sg2042/block/partitions/amiga.c

140 lines
3.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* fs/partitions/amiga.c
*
* Code extracted from drivers/block/genhd.c
*
* Copyright (C) 1991-1998 Linus Torvalds
* Re-organised Feb 1998 Russell King
*/
#define pr_fmt(fmt) fmt
#include <linux/types.h>
#include <linux/affs_hardblocks.h>
#include "check.h"
static __inline__ u32
checksum_block(__be32 *m, int size)
{
u32 sum = 0;
while (size--)
sum += be32_to_cpu(*m++);
return sum;
}
int amiga_partition(struct parsed_partitions *state)
{
Sector sect;
unsigned char *data;
struct RigidDiskBlock *rdb;
struct PartitionBlock *pb;
int start_sect, nr_sects, blk, part, res = 0;
int blksize = 1; /* Multiplier for disk block size */
int slot = 1;
char b[BDEVNAME_SIZE];
for (blk = 0; ; blk++, put_dev_sector(sect)) {
if (blk == RDB_ALLOCATION_LIMIT)
goto rdb_done;
data = read_part_sector(state, blk, &sect);
if (!data) {
pr_err("Dev %s: unable to read RDB block %d\n",
bdevname(state->bdev, b), blk);
res = -1;
goto rdb_done;
}
if (*(__be32 *)data != cpu_to_be32(IDNAME_RIGIDDISK))
continue;
rdb = (struct RigidDiskBlock *)data;
if (checksum_block((__be32 *)data, be32_to_cpu(rdb->rdb_SummedLongs) & 0x7F) == 0)
break;
/* Try again with 0xdc..0xdf zeroed, Windows might have
* trashed it.
*/
*(__be32 *)(data+0xdc) = 0;
if (checksum_block((__be32 *)data,
be32_to_cpu(rdb->rdb_SummedLongs) & 0x7F)==0) {
pr_err("Trashed word at 0xd0 in block %d ignored in checksum calculation\n",
blk);
break;
}
pr_err("Dev %s: RDB in block %d has bad checksum\n",
bdevname(state->bdev, b), blk);
}
/* blksize is blocks per 512 byte standard block */
blksize = be32_to_cpu( rdb->rdb_BlockBytes ) / 512;
{
char tmp[7 + 10 + 1 + 1];
/* Be more informative */
snprintf(tmp, sizeof(tmp), " RDSK (%d)", blksize * 512);
strlcat(state->pp_buf, tmp, PAGE_SIZE);
}
blk = be32_to_cpu(rdb->rdb_PartitionList);
put_dev_sector(sect);
for (part = 1; blk>0 && part<=16; part++, put_dev_sector(sect)) {
blk *= blksize; /* Read in terms partition table understands */
data = read_part_sector(state, blk, &sect);
if (!data) {
pr_err("Dev %s: unable to read partition block %d\n",
bdevname(state->bdev, b), blk);
res = -1;
goto rdb_done;
}
pb = (struct PartitionBlock *)data;
blk = be32_to_cpu(pb->pb_Next);
if (pb->pb_ID != cpu_to_be32(IDNAME_PARTITION))
continue;
if (checksum_block((__be32 *)pb, be32_to_cpu(pb->pb_SummedLongs) & 0x7F) != 0 )
continue;
/* Tell Kernel about it */
nr_sects = (be32_to_cpu(pb->pb_Environment[10]) + 1 -
be32_to_cpu(pb->pb_Environment[9])) *
be32_to_cpu(pb->pb_Environment[3]) *
be32_to_cpu(pb->pb_Environment[5]) *
blksize;
if (!nr_sects)
continue;
start_sect = be32_to_cpu(pb->pb_Environment[9]) *
be32_to_cpu(pb->pb_Environment[3]) *
be32_to_cpu(pb->pb_Environment[5]) *
blksize;
put_partition(state,slot++,start_sect,nr_sects);
{
/* Be even more informative to aid mounting */
char dostype[4];
char tmp[42];
__be32 *dt = (__be32 *)dostype;
*dt = pb->pb_Environment[16];
if (dostype[3] < ' ')
snprintf(tmp, sizeof(tmp), " (%c%c%c^%c)",
dostype[0], dostype[1],
dostype[2], dostype[3] + '@' );
else
snprintf(tmp, sizeof(tmp), " (%c%c%c%c)",
dostype[0], dostype[1],
dostype[2], dostype[3]);
strlcat(state->pp_buf, tmp, PAGE_SIZE);
snprintf(tmp, sizeof(tmp), "(res %d spb %d)",
be32_to_cpu(pb->pb_Environment[6]),
be32_to_cpu(pb->pb_Environment[4]));
strlcat(state->pp_buf, tmp, PAGE_SIZE);
}
res = 1;
}
strlcat(state->pp_buf, "\n", PAGE_SIZE);
rdb_done:
return res;
}