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Fix bug with >256 cylinders. 

Allow our functions to return a non-zero, non-error status (since the
INT 13 Extensions Check has to return the API version in the register
that is otherwise always used for the error code).

Report a non-zero API version from the INT 13 Extensions Check; GRUB
now uses extended reads.
This commit is contained in:
Michael Brown 2006-06-08 19:28:08 +00:00
parent ad1aca0634
commit 17eea9f933
1 changed files with 18 additions and 15 deletions
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33
src/arch/i386/interface/pcbios/int13.c
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@ -115,7 +115,7 @@ static int int13_rw_sectors ( struct int13_drive *drive,
userptr_t buffer;
/* Calculate parameters */
cylinder = ( ( ( ix86->regs.cl & 0xc0 ) << 8 ) | ix86->regs.ch );
cylinder = ( ( ( ix86->regs.cl & 0xc0 ) << 2 ) | ix86->regs.ch );
assert ( cylinder < drive->cylinders );
head = ix86->regs.dh;
assert ( head < drive->heads );
@ -133,12 +133,12 @@ static int int13_rw_sectors ( struct int13_drive *drive,
if ( blockdev->blksize != INT13_BLKSIZE ) {
DBG ( "Invalid blocksize (%zd) for non-extended read/write\n",
blockdev->blksize );
return INT13_STATUS_INVALID;
return -INT13_STATUS_INVALID;
}
/* Read from / write to block device */
if ( io ( blockdev, lba, count, buffer ) != 0 )
return INT13_STATUS_READ_ERROR;
return -INT13_STATUS_READ_ERROR;
return 0;
}
@ -214,7 +214,7 @@ static int int13_get_parameters ( struct int13_drive *drive,
* @v bx 0x55aa
* @ret bx 0xaa55
* @ret cx Extensions API support bitmap
* @ret status Status code
* @ret status Status code / API version
*/
static int int13_extension_check ( struct int13_drive *drive __unused,
struct i386_all_regs *ix86 ) {
@ -222,9 +222,9 @@ static int int13_extension_check ( struct int13_drive *drive __unused,
DBG ( "INT 13 extensions installation check\n" );
ix86->regs.bx = 0xaa55;
ix86->regs.cx = INT13_EXTENSION_LINEAR;
return 0;
return INT13_EXTENSION_VER_1_X;
} else {
return INT13_STATUS_INVALID;
return -INT13_STATUS_INVALID;
}
}
@ -259,7 +259,7 @@ static int int13_extended_rw ( struct int13_drive *drive,
/* Read from / write to block device */
if ( io ( blockdev, lba, count, buffer ) != 0 )
return INT13_STATUS_READ_ERROR;
return -INT13_STATUS_READ_ERROR;
return 0;
}
@ -322,6 +322,7 @@ static int int13_get_extended_parameters ( struct int13_drive *drive,
*
*/
static void int13 ( struct i386_all_regs *ix86 ) {
int command = ix86->regs.ah;
struct int13_drive *drive;
int status;
@ -329,10 +330,9 @@ static void int13 ( struct i386_all_regs *ix86 ) {
if ( drive->drive != ix86->regs.dl )
continue;
DBG ( "INT 13,%02x (%02x): ", ix86->regs.ah,
ix86->regs.dl );
switch ( ix86->regs.ah ) {
DBG ( "INT 13,%02x (%02x): ", command, drive->drive );
switch ( command ) {
case INT13_RESET:
status = int13_reset ( drive, ix86 );
break;
@ -362,18 +362,21 @@ static void int13 ( struct i386_all_regs *ix86 ) {
break;
default:
DBG ( "Unrecognised INT 13\n" );
status = INT13_STATUS_INVALID;
status = -INT13_STATUS_INVALID;
break;
}
/* Store status for INT 13,01 */
drive->last_status = status;
/* All functions return status via %ah and CF */
ix86->regs.ah = status;
if ( status ) {
/* Negative status indicates an error */
if ( status < 0 ) {
ix86->flags |= CF;
status = -status;
DBG ( "INT13 failed with status %x\n", status );
}
ix86->regs.ah = status;
/* Set OF to indicate to wrapper not to chain this call */
ix86->flags |= OF;
}