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/*
* boot driver for BIOS devices with partitions
* devbios must be called first
*/
#include "u.h"
#include "lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "ureg.h"
#include "error.h"
#include "sd.h"
#include "fs.h"
long biosread(Fs *, void *, long);
vlong biosseek(Fs *fs, vlong off);
extern SDifc sdbiosifc;
extern int onlybios0, biosinited;
int
biosverify(SDunit* )
{
if (onlybios0 || !biosinited)
return 0;
return 1;
}
int
biosonline(SDunit* unit)
{
if (onlybios0 || !biosinited || !unit)
return 0;
unit->sectors = 1UL << 30; /* a bunch */
unit->secsize = 512; /* conventional */
return 1;
}
static int
biosrio(SDreq* r)
{
int nb;
long got;
vlong len, off;
uchar *p;
Fs fs; /* just for fs->dev, which is zero */
if (onlybios0 || !biosinited)
return SDeio;
/*
* Most SCSI commands can be passed unchanged except for
* the padding on the end. The few which require munging
* are not used internally. Mode select/sense(6) could be
* converted to the 10-byte form but it's not worth the
* effort. Read/write(6) are easy.
*/
r->rlen = 0;
r->status = SDok;
switch(r->cmd[0]){
case 0x08: /* read */
case 0x28: /* read */
if (r->cmd[0] == 0x08)
panic("biosrio: 0x08 read op\n");
off = r->cmd[2]<<24 | r->cmd[3]<<16 | r->cmd[4]<<8 | r->cmd[5];
nb = r->cmd[7]<<8 | r->cmd[8]; /* often 4 */
USED(nb); /* is nb*512 == r->dlen? */
memset(&fs, 0, sizeof fs);
biosseek(&fs, off*512);
got = biosread(&fs, r->data, r->dlen);
if (got < 0)
r->status = SDeio;
else
r->rlen = got;
break;
case 0x0A: /* write */
case 0x2A: /* write */
r->status = SDeio; /* boot programs don't write */
break;
case 0x25: /* read capacity */
/*
* Read capacity returns the LBA of the last sector.
*/
len = r->unit->sectors - 1;
p = r->data;
*p++ = len>>24;
*p++ = len>>16;
*p++ = len>>8;
*p++ = len;
len = r->unit->secsize;
*p++ = len>>24;
*p++ = len>>16;
*p++ = len>>8;
*p = len;
r->data = (char *)r->data + 8;
return SDok;
case 0x9E: /* long read capacity */
/*
* Read capacity returns the LBA of the last sector.
*/
len = r->unit->sectors - 1;
p = r->data;
*p++ = len>>56;
*p++ = len>>48;
*p++ = len>>40;
*p++ = len>>32;
*p++ = len>>24;
*p++ = len>>16;
*p++ = len>>8;
*p++ = len;
len = r->unit->secsize;
*p++ = len>>24;
*p++ = len>>16;
*p++ = len>>8;
*p = len;
r->data = (char *)r->data + 8;
return SDok;
/* ignore others */
}
return r->status;
}
SDev*
biosid(SDev* sdev)
{
for (; sdev; sdev = sdev->next)
if (sdev->ifc == &sdbiosifc)
sdev->idno = 'B';
return sdev;
}
static SDev*
biospnp(void)
{
SDev *sdev;
/* 9pxeload can't use bios int 13 calls; they wedge the machine */
if (pxe || getconf("*nobiosload") != nil || onlybios0 || !biosinited)
return nil;
if((sdev = malloc(sizeof(SDev))) != nil) {
sdev->ifc = &sdbiosifc;
sdev->index = -1;
sdev->nunit = 1;
}
return sdev;
}
SDifc sdbiosifc = {
"bios", /* name */
biospnp, /* pnp */
nil, /* legacy */
biosid, /* id */
nil, /* enable */
nil, /* disable */
biosverify, /* verify */
biosonline, /* online */
biosrio, /* rio */
nil, /* rctl */
nil, /* wctl */
scsibio, /* bio */
};
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