blob: 771923efe858f05af3d8b6d2608d960abf9e635b [file] [log] [blame]
/*
* pc partition support
*
* Copyright (C) 2004 Stefan Reinauer
*
* This code is based (and copied in many places) from
* mac partition support by Samuel Rydh (samuel@ibrium.se)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2
*
*/
#include "config.h"
#include "libopenbios/bindings.h"
#include "libopenbios/load.h"
#include "libc/byteorder.h"
#include "libc/vsprintf.h"
#include "packages.h"
//#define DEBUG_PC_PARTS
#ifdef DEBUG_PC_PARTS
#define DPRINTF(fmt, args...) \
do { printk(fmt , ##args); } while (0)
#else
#define DPRINTF(fmt, args...)
#endif
typedef struct {
xt_t seek_xt, read_xt;
ucell offs_hi, offs_lo;
ucell size_hi, size_lo;
phandle_t filesystem_ph;
} pcparts_info_t;
DECLARE_NODE( pcparts, INSTALL_OPEN, sizeof(pcparts_info_t), "+/packages/pc-parts" );
#define SEEK( pos ) ({ DPUSH(pos); call_parent(di->seek_xt); POP(); })
#define READ( buf, size ) ({ PUSH(pointer2cell(buf)); PUSH(size); call_parent(di->read_xt); POP(); })
/* three helper functions */
static inline int has_pc_valid_partition(unsigned char *sect)
{
/* Make sure the partition table contains at least one valid entry */
return (sect[0x1c2] != 0 || sect[0x1d2] != 0 || sect[0x1e2] != 0);
}
static inline int has_pc_part_magic(unsigned char *sect)
{
return sect[0x1fe]==0x55 && sect[0x1ff]==0xAA;
}
static inline int is_pc_extended_part(unsigned char type)
{
return type==5 || type==0xf || type==0x85;
}
/* ( open -- flag ) */
static void
pcparts_open( pcparts_info_t *di )
{
char *str = my_args_copy();
char *argstr = strdup("");
char *parstr = strdup("");
int bs, parnum=-1;
int found = 0;
phandle_t ph;
ducell offs, size;
/* Layout of PC partition table */
struct pc_partition {
unsigned char boot;
unsigned char head;
unsigned char sector;
unsigned char cyl;
unsigned char type;
unsigned char e_head;
unsigned char e_sector;
unsigned char e_cyl;
u32 start_sect; /* unaligned little endian */
u32 nr_sects; /* ditto */
} *p, *partition;
unsigned char buf[512];
DPRINTF("pcparts_open '%s'\n", str );
/*
Arguments that we accept:
id: [0-7]
[(id)][,][filespec]
*/
if ( strlen(str) ) {
/* Detect the arguments */
if ((*str >= '0' && *str <= '7') || (*str == ',')) {
push_str(str);
PUSH(',');
fword("left-parse-string");
parstr = pop_fstr_copy();
argstr = pop_fstr_copy();
} else {
argstr = str;
}
/* Convert the id to a partition number */
if (parstr && strlen(parstr))
parnum = atol(parstr);
}
/* Make sure argstr is not null */
if (argstr == NULL)
argstr = strdup("");
DPRINTF("parstr: %s argstr: %s parnum: %d\n", parstr, argstr, parnum);
free(parstr);
if( parnum < 0 )
parnum = 0;
di->filesystem_ph = 0;
di->read_xt = find_parent_method("read");
di->seek_xt = find_parent_method("seek");
SEEK( 0 );
if( READ(buf, 512) != 512 )
RET(0);
/* Check Magic */
if (!has_pc_part_magic(buf)) {
DPRINTF("pc partition magic not found.\n");
RET(0);
}
/* Actual partition data */
partition = (struct pc_partition *) (buf + 0x1be);
/* Make sure we use a copy accessible from an aligned pointer (some archs
e.g. SPARC will crash otherwise) */
p = malloc(sizeof(struct pc_partition));
bs = 512;
if (parnum < 4) {
/* primary partition */
partition += parnum;
memcpy(p, partition, sizeof(struct pc_partition));
if (p->type == 0 || is_pc_extended_part(p->type)) {
DPRINTF("partition %d does not exist\n", parnum+1 );
RET( 0 );
}
offs = (long long)(__le32_to_cpu(p->start_sect)) * bs;
di->offs_hi = offs >> BITS;
di->offs_lo = offs & (ucell) -1;
size = (long long)(__le32_to_cpu(p->nr_sects)) * bs;
di->size_hi = size >> BITS;
di->size_lo = size & (ucell) -1;
DPRINTF("Primary partition at sector %x\n", __le32_to_cpu(p->start_sect));
found = 1;
} else {
/* Extended partition */
int i, cur_part;
unsigned long ext_start, cur_table;
/* Search for the extended partition
* which contains logical partitions */
for (i = 0; i < 4; i++) {
if (is_pc_extended_part(p[i].type))
break;
}
if (i >= 4) {
DPRINTF("Extended partition not found\n");
RET( 0 );
}
DPRINTF("Extended partition at %d\n", i+1);
/* Visit each logical partition labels */
ext_start = __le32_to_cpu(p[i].start_sect);
cur_table = ext_start;
cur_part = 4;
while (cur_part <= parnum) {
DPRINTF("cur_part=%d at %lx\n", cur_part, cur_table);
SEEK( cur_table * bs );
if( READ(buf, sizeof(512)) != sizeof(512) )
RET( 0 );
if (!has_pc_part_magic(buf)) {
DPRINTF("Extended partition has no magic\n");
break;
}
/* Read the extended partition, making sure we are aligned again */
partition = (struct pc_partition *) (buf + 0x1be);
memcpy(p, partition, sizeof(struct pc_partition));
/* First entry is the logical partition */
if (cur_part == parnum) {
if (p->type == 0) {
DPRINTF("Partition %d is empty\n", parnum+1);
RET( 0 );
}
offs = (long long)(cur_table+__le32_to_cpu(p->start_sect)) * bs;
di->offs_hi = offs >> BITS;
di->offs_lo = offs & (ucell) -1;
size = (long long)__le32_to_cpu(p->nr_sects) * bs;
di->size_hi = size >> BITS;
di->size_lo = size & (ucell) -1;
found = 1;
break;
}
/* Second entry is link to next partition */
if (!is_pc_extended_part(p[1].type)) {
DPRINTF("no link\n");
break;
}
cur_table = ext_start + __le32_to_cpu(p[1].start_sect);
cur_part++;
}
if (!found) {
DPRINTF("Logical partition %d does not exist\n", parnum+1);
RET( 0 );
}
}
free(p);
if (found) {
/* We have a valid partition - so probe for a filesystem at the current offset */
DPRINTF("pc-parts: about to probe for fs\n");
DPUSH( offs );
PUSH_ih( my_parent() );
parword("find-filesystem");
DPRINTF("pc-parts: done fs probe\n");
ph = POP_ph();
if( ph ) {
DPRINTF("pc-parts: filesystem found with ph " FMT_ucellx " and args %s\n", ph, argstr);
di->filesystem_ph = ph;
/* If we have been asked to open a particular file, interpose the filesystem package with
the passed filename as an argument */
if (strlen(argstr)) {
push_str( argstr );
PUSH_ph( ph );
fword("interpose");
}
} else {
DPRINTF("pc-parts: no filesystem found; bypassing misc-files interpose\n");
}
free( str );
RET( -1 );
} else {
DPRINTF("pc-parts: unable to locate partition\n");
free( str );
RET( 0 );
}
}
/* ( block0 -- flag? ) */
static void
pcparts_probe( pcparts_info_t *dummy )
{
unsigned char *buf = (unsigned char *)cell2pointer(POP());
DPRINTF("probing for PC partitions\n");
/* We also check that at least one valid partition exists; this is because
some CDs seem broken in that they have a partition table but it is empty
e.g. MorphOS. */
RET ( has_pc_part_magic(buf) && has_pc_valid_partition(buf) );
}
/* ( -- type offset.d size.d ) */
static void
pcparts_get_info( pcparts_info_t *di )
{
DPRINTF("PC get_info\n");
PUSH( -1 ); /* no type */
PUSH( di->offs_lo );
PUSH( di->offs_hi );
PUSH( di->size_lo );
PUSH( di->size_hi );
}
static void
pcparts_block_size( __attribute__((unused))pcparts_info_t *di )
{
PUSH(512);
}
static void
pcparts_initialize( pcparts_info_t *di )
{
fword("register-partition-package");
}
/* ( pos.d -- status ) */
static void
pcparts_seek(pcparts_info_t *di )
{
long long pos = DPOP();
long long offs, size;
DPRINTF("pcparts_seek %llx:\n", pos);
/* Seek is invalid if we reach the end of the device */
size = ((ducell)di->size_hi << BITS) | di->size_lo;
if (pos > size)
RET( -1 );
/* Calculate the seek offset for the parent */
offs = ((ducell)di->offs_hi << BITS) | di->offs_lo;
offs += pos;
DPUSH(offs);
DPRINTF("pcparts_seek parent offset %llx:\n", offs);
call_package(di->seek_xt, my_parent());
}
/* ( buf len -- actlen ) */
static void
pcparts_read(pcparts_info_t *di )
{
DPRINTF("pcparts_read\n");
/* Pass the read back up to the parent */
call_package(di->read_xt, my_parent());
}
/* ( addr -- size ) */
static void
pcparts_load( __attribute__((unused))pcparts_info_t *di )
{
/* Invoke the loader */
load(my_self());
}
/* ( pathstr len -- ) */
static void
pcparts_dir( pcparts_info_t *di )
{
if ( di->filesystem_ph ) {
PUSH( my_self() );
push_str("dir");
PUSH( di->filesystem_ph );
fword("find-method");
POP();
fword("execute");
} else {
forth_printf("pc-parts: Unable to determine filesystem\n");
POP();
POP();
}
}
NODE_METHODS( pcparts ) = {
{ "probe", pcparts_probe },
{ "open", pcparts_open },
{ "seek", pcparts_seek },
{ "read", pcparts_read },
{ "load", pcparts_load },
{ "dir", pcparts_dir },
{ "get-info", pcparts_get_info },
{ "block-size", pcparts_block_size },
{ NULL, pcparts_initialize },
};
void
pcparts_init( void )
{
REGISTER_NODE( pcparts );
}