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[pxe] Separate parent PXE API caller from UNDINET driver 

Calling the parent PXE stack (the stack that loaded us, for
undionly.kkpxe) can be useful for more than UNDI calls; for instance,
it lets us get cached DHCP packets to avoid re-DHCP when working with
embedded images.

Signed-off-by: Marty Connor <mdc@etherboot.org>
This commit is contained in:
Joshua Oreman 2009-12-08 03:38:50 -05:00 committed by Marty Connor
parent 2d58a62330
commit 337e1ed4b4
6 changed files with 263 additions and 216 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
src/arch/i386/Makefile
View File

@ -80,6 +80,7 @@ SRCDIRS += arch/i386/drivers
SRCDIRS += arch/i386/drivers/net
SRCDIRS += arch/i386/interface/pcbios
SRCDIRS += arch/i386/interface/pxe
SRCDIRS += arch/i386/interface/pxeparent
SRCDIRS += arch/i386/interface/syslinux
SRCDIRS += arch/i386/hci/commands

4
src/arch/i386/drivers/net/undiisr.S
View File

@ -31,7 +31,7 @@ undiisr:
movw %ax, %ds
/* Check that we have an UNDI entry point */
cmpw $0, undinet_entry_point
cmpw $0, pxeparent_entry_point
je chain
/* Issue UNDI API call */
@ -42,7 +42,7 @@ undiisr:
pushw %es
pushw %di
pushw %bx
lcall *undinet_entry_point
lcall *pxeparent_entry_point
cli /* Just in case */
addw $6, %sp
cmpw $PXENV_UNDI_ISR_OUT_OURS, funcflag

261
src/arch/i386/drivers/net/undinet.c
View File

@ -32,6 +32,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
#include <gpxe/ethernet.h>
#include <undi.h>
#include <undinet.h>
#include <pxeparent.h>
/** @file
@ -62,178 +63,8 @@ struct undi_nic {
static void undinet_close ( struct net_device *netdev );
/*****************************************************************************
*
* UNDI API call
*
*****************************************************************************
*/
/**
* Name UNDI API call
*
* @v function API call number
* @ret name API call name
*/
static inline __attribute__ (( always_inline )) const char *
undinet_function_name ( unsigned int function ) {
switch ( function ) {
case PXENV_START_UNDI:
return "PXENV_START_UNDI";
case PXENV_STOP_UNDI:
return "PXENV_STOP_UNDI";
case PXENV_UNDI_STARTUP:
return "PXENV_UNDI_STARTUP";
case PXENV_UNDI_CLEANUP:
return "PXENV_UNDI_CLEANUP";
case PXENV_UNDI_INITIALIZE:
return "PXENV_UNDI_INITIALIZE";
case PXENV_UNDI_RESET_ADAPTER:
return "PXENV_UNDI_RESET_ADAPTER";
case PXENV_UNDI_SHUTDOWN:
return "PXENV_UNDI_SHUTDOWN";
case PXENV_UNDI_OPEN:
return "PXENV_UNDI_OPEN";
case PXENV_UNDI_CLOSE:
return "PXENV_UNDI_CLOSE";
case PXENV_UNDI_TRANSMIT:
return "PXENV_UNDI_TRANSMIT";
case PXENV_UNDI_SET_MCAST_ADDRESS:
return "PXENV_UNDI_SET_MCAST_ADDRESS";
case PXENV_UNDI_SET_STATION_ADDRESS:
return "PXENV_UNDI_SET_STATION_ADDRESS";
case PXENV_UNDI_SET_PACKET_FILTER:
return "PXENV_UNDI_SET_PACKET_FILTER";
case PXENV_UNDI_GET_INFORMATION:
return "PXENV_UNDI_GET_INFORMATION";
case PXENV_UNDI_GET_STATISTICS:
return "PXENV_UNDI_GET_STATISTICS";
case PXENV_UNDI_CLEAR_STATISTICS:
return "PXENV_UNDI_CLEAR_STATISTICS";
case PXENV_UNDI_INITIATE_DIAGS:
return "PXENV_UNDI_INITIATE_DIAGS";
case PXENV_UNDI_FORCE_INTERRUPT:
return "PXENV_UNDI_FORCE_INTERRUPT";
case PXENV_UNDI_GET_MCAST_ADDRESS:
return "PXENV_UNDI_GET_MCAST_ADDRESS";
case PXENV_UNDI_GET_NIC_TYPE:
return "PXENV_UNDI_GET_NIC_TYPE";
case PXENV_UNDI_GET_IFACE_INFO:
return "PXENV_UNDI_GET_IFACE_INFO";
/*
* Duplicate case value; this is a bug in the PXE specification.
*
* case PXENV_UNDI_GET_STATE:
* return "PXENV_UNDI_GET_STATE";
*/
case PXENV_UNDI_ISR:
return "PXENV_UNDI_ISR";
default:
return "UNKNOWN API CALL";
}
}
/**
* UNDI parameter block
*
* Used as the paramter block for all UNDI API calls. Resides in base
* memory.
*/
static union u_PXENV_ANY __bss16 ( undinet_params );
#define undinet_params __use_data16 ( undinet_params )
/** UNDI entry point
*
* Used as the indirection vector for all UNDI API calls. Resides in
* base memory.
*/
SEGOFF16_t __bss16 ( undinet_entry_point );
#define undinet_entry_point __use_data16 ( undinet_entry_point )
/**
* Issue UNDI API call
*
* @v undinic UNDI NIC
* @v function API call number
* @v params UNDI parameter block
* @v params_len Length of UNDI parameter block
* @ret rc Return status code
*/
static int undinet_call ( struct undi_nic *undinic, unsigned int function,
void *params, size_t params_len ) {
PXENV_EXIT_t exit;
int discard_b, discard_D;
int rc;
/* Copy parameter block and entry point */
assert ( params_len <= sizeof ( undinet_params ) );
memcpy ( &undinet_params, params, params_len );
/* Call real-mode entry point. This calling convention will
* work with both the !PXE and the PXENV+ entry points.
*/
__asm__ __volatile__ ( REAL_CODE ( "pushw %%es\n\t"
"pushw %%di\n\t"
"pushw %%bx\n\t"
"lcall *undinet_entry_point\n\t"
"addw $6, %%sp\n\t" )
: "=a" ( exit ), "=b" ( discard_b ),
"=D" ( discard_D )
: "b" ( function ),
"D" ( __from_data16 ( &undinet_params ) )
: "ecx", "edx", "esi", "ebp" );
/* UNDI API calls may rudely change the status of A20 and not
* bother to restore it afterwards. Intel is known to be
* guilty of this.
*
* Note that we will return to this point even if A20 gets
* screwed up by the UNDI driver, because Etherboot always
* resides in an even megabyte of RAM.
*/
gateA20_set();
/* Determine return status code based on PXENV_EXIT and
* PXENV_STATUS
*/
if ( exit == PXENV_EXIT_SUCCESS ) {
rc = 0;
} else {
rc = -undinet_params.Status;
/* Paranoia; don't return success for the combination
* of PXENV_EXIT_FAILURE but PXENV_STATUS_SUCCESS
*/
if ( rc == 0 )
rc = -EIO;
}
/* If anything goes wrong, print as much debug information as
* it's possible to give.
*/
if ( rc != 0 ) {
SEGOFF16_t rm_params = {
.segment = rm_ds,
.offset = __from_data16 ( &undinet_params ),
};
DBGC ( undinic, "UNDINIC %p %s failed: %s\n", undinic,
undinet_function_name ( function ), strerror ( rc ) );
DBGC ( undinic, "UNDINIC %p parameters at %04x:%04x length "
"%#02zx, entry point at %04x:%04x\n", undinic,
rm_params.segment, rm_params.offset, params_len,
undinet_entry_point.segment,
undinet_entry_point.offset );
DBGC ( undinic, "UNDINIC %p parameters provided:\n", undinic );
DBGC_HDA ( undinic, rm_params, params, params_len );
DBGC ( undinic, "UNDINIC %p parameters returned:\n", undinic );
DBGC_HDA ( undinic, rm_params, &undinet_params, params_len );
}
/* Copy parameter block back */
memcpy ( params, &undinet_params, params_len );
return rc;
}
/** Address of UNDI entry point */
static SEGOFF16_t undinet_entry;
/*****************************************************************************
*
@ -336,7 +167,6 @@ static struct s_PXENV_UNDI_TBD __data16 ( undinet_tbd );
*/
static int undinet_transmit ( struct net_device *netdev,
struct io_buffer *iobuf ) {
struct undi_nic *undinic = netdev->priv;
struct s_PXENV_UNDI_TRANSMIT undi_transmit;
size_t len = iob_len ( iobuf );
int rc;
@ -369,9 +199,9 @@ static int undinet_transmit ( struct net_device *netdev,
undinet_tbd.Xmit.offset = __from_data16 ( basemem_packet );
/* Issue PXE API call */
if ( ( rc = undinet_call ( undinic, PXENV_UNDI_TRANSMIT,
&undi_transmit,
sizeof ( undi_transmit ) ) ) != 0 )
if ( ( rc = pxeparent_call ( undinet_entry, PXENV_UNDI_TRANSMIT,
&undi_transmit,
sizeof ( undi_transmit ) ) ) != 0 )
goto done;
/* Free I/O buffer */
@ -441,8 +271,9 @@ static void undinet_poll ( struct net_device *netdev ) {
/* Run through the ISR loop */
while ( 1 ) {
if ( ( rc = undinet_call ( undinic, PXENV_UNDI_ISR, &undi_isr,
sizeof ( undi_isr ) ) ) != 0 )
if ( ( rc = pxeparent_call ( undinet_entry, PXENV_UNDI_ISR,
&undi_isr,
sizeof ( undi_isr ) ) ) != 0 )
break;
switch ( undi_isr.FuncFlag ) {
case PXENV_UNDI_ISR_OUT_TRANSMIT:
@ -538,8 +369,8 @@ static int undinet_open ( struct net_device *netdev ) {
*/
memcpy ( undi_set_address.StationAddress, netdev->ll_addr,
sizeof ( undi_set_address.StationAddress ) );
undinet_call ( undinic, PXENV_UNDI_SET_STATION_ADDRESS,
&undi_set_address, sizeof ( undi_set_address ) );
pxeparent_call ( undinet_entry, PXENV_UNDI_SET_STATION_ADDRESS,
&undi_set_address, sizeof ( undi_set_address ) );
/* Open NIC. We ask for promiscuous operation, since it's the
* only way to ask for all multicast addresses. On any
@ -548,8 +379,8 @@ static int undinet_open ( struct net_device *netdev ) {
*/
memset ( &undi_open, 0, sizeof ( undi_open ) );
undi_open.PktFilter = ( FLTR_DIRECTED | FLTR_BRDCST | FLTR_PRMSCS );
if ( ( rc = undinet_call ( undinic, PXENV_UNDI_OPEN, &undi_open,
sizeof ( undi_open ) ) ) != 0 )
if ( ( rc = pxeparent_call ( undinet_entry, PXENV_UNDI_OPEN,
&undi_open, sizeof ( undi_open ) ) ) != 0 )
goto err;
DBGC ( undinic, "UNDINIC %p opened\n", undinic );
@ -574,8 +405,9 @@ static void undinet_close ( struct net_device *netdev ) {
/* Ensure ISR has exited cleanly */
while ( undinic->isr_processing ) {
undi_isr.FuncFlag = PXENV_UNDI_ISR_IN_GET_NEXT;
if ( ( rc = undinet_call ( undinic, PXENV_UNDI_ISR, &undi_isr,
sizeof ( undi_isr ) ) ) != 0 )
if ( ( rc = pxeparent_call ( undinet_entry, PXENV_UNDI_ISR,
&undi_isr,
sizeof ( undi_isr ) ) ) != 0 )
break;
switch ( undi_isr.FuncFlag ) {
case PXENV_UNDI_ISR_OUT_TRANSMIT:
@ -590,8 +422,8 @@ static void undinet_close ( struct net_device *netdev ) {
}
/* Close NIC */
undinet_call ( undinic, PXENV_UNDI_CLOSE, &undi_close,
sizeof ( undi_close ) );
pxeparent_call ( undinet_entry, PXENV_UNDI_CLOSE,
&undi_close, sizeof ( undi_close ) );
/* Disable interrupt and unhook ISR */
disable_irq ( undinic->irq );
@ -651,7 +483,7 @@ int undinet_probe ( struct undi_device *undi ) {
undi_set_drvdata ( undi, netdev );
netdev->dev = &undi->dev;
memset ( undinic, 0, sizeof ( *undinic ) );
undinet_entry_point = undi->entry;
undinet_entry = undi->entry;
DBGC ( undinic, "UNDINIC %p using UNDI %p\n", undinic, undi );
/* Hook in UNDI stack */
@ -662,9 +494,9 @@ int undinet_probe ( struct undi_device *undi ) {
start_undi.DX = undi->isapnp_read_port;
start_undi.ES = BIOS_SEG;
start_undi.DI = find_pnp_bios();
if ( ( rc = undinet_call ( undinic, PXENV_START_UNDI,
&start_undi,
sizeof ( start_undi ) ) ) != 0 )
if ( ( rc = pxeparent_call ( undinet_entry, PXENV_START_UNDI,
&start_undi,
sizeof ( start_undi ) ) ) != 0 )
goto err_start_undi;
}
undi->flags |= UNDI_FL_STARTED;
@ -672,22 +504,23 @@ int undinet_probe ( struct undi_device *undi ) {
/* Bring up UNDI stack */
if ( ! ( undi->flags & UNDI_FL_INITIALIZED ) ) {
memset ( &undi_startup, 0, sizeof ( undi_startup ) );
if ( ( rc = undinet_call ( undinic, PXENV_UNDI_STARTUP,
&undi_startup,
sizeof ( undi_startup ) ) ) != 0 )
if ( ( rc = pxeparent_call ( undinet_entry, PXENV_UNDI_STARTUP,
&undi_startup,
sizeof ( undi_startup ) ) ) != 0 )
goto err_undi_startup;
memset ( &undi_initialize, 0, sizeof ( undi_initialize ) );
if ( ( rc = undinet_call ( undinic, PXENV_UNDI_INITIALIZE,
&undi_initialize,
sizeof ( undi_initialize ))) != 0 )
if ( ( rc = pxeparent_call ( undinet_entry,
PXENV_UNDI_INITIALIZE,
&undi_initialize,
sizeof ( undi_initialize ))) != 0 )
goto err_undi_initialize;
}
undi->flags |= UNDI_FL_INITIALIZED;
/* Get device information */
memset ( &undi_info, 0, sizeof ( undi_info ) );
if ( ( rc = undinet_call ( undinic, PXENV_UNDI_GET_INFORMATION,
&undi_info, sizeof ( undi_info ) ) ) != 0 )
if ( ( rc = pxeparent_call ( undinet_entry, PXENV_UNDI_GET_INFORMATION,
&undi_info, sizeof ( undi_info ) ) ) != 0 )
goto err_undi_get_information;
memcpy ( netdev->hw_addr, undi_info.PermNodeAddress, ETH_ALEN );
undinic->irq = undi_info.IntNumber;
@ -701,9 +534,9 @@ int undinet_probe ( struct undi_device *undi ) {
/* Get interface information */
memset ( &undi_iface, 0, sizeof ( undi_iface ) );
if ( ( rc = undinet_call ( undinic, PXENV_UNDI_GET_IFACE_INFO,
&undi_iface,
sizeof ( undi_iface ) ) ) != 0 )
if ( ( rc = pxeparent_call ( undinet_entry, PXENV_UNDI_GET_IFACE_INFO,
&undi_iface,
sizeof ( undi_iface ) ) ) != 0 )
goto err_undi_get_iface_info;
DBGC ( undinic, "UNDINIC %p has type %s, speed %d, flags %08x\n",
undinic, undi_iface.IfaceType, undi_iface.LinkSpeed,
@ -732,17 +565,17 @@ int undinet_probe ( struct undi_device *undi ) {
err_undi_initialize:
/* Shut down UNDI stack */
memset ( &undi_shutdown, 0, sizeof ( undi_shutdown ) );
undinet_call ( undinic, PXENV_UNDI_SHUTDOWN, &undi_shutdown,
sizeof ( undi_shutdown ) );
pxeparent_call ( undinet_entry, PXENV_UNDI_SHUTDOWN, &undi_shutdown,
sizeof ( undi_shutdown ) );
memset ( &undi_cleanup, 0, sizeof ( undi_cleanup ) );
undinet_call ( undinic, PXENV_UNDI_CLEANUP, &undi_cleanup,
sizeof ( undi_cleanup ) );
pxeparent_call ( undinet_entry, PXENV_UNDI_CLEANUP, &undi_cleanup,
sizeof ( undi_cleanup ) );
undi->flags &= ~UNDI_FL_INITIALIZED;
err_undi_startup:
/* Unhook UNDI stack */
memset ( &stop_undi, 0, sizeof ( stop_undi ) );
undinet_call ( undinic, PXENV_STOP_UNDI, &stop_undi,
sizeof ( stop_undi ) );
pxeparent_call ( undinet_entry, PXENV_STOP_UNDI, &stop_undi,
sizeof ( stop_undi ) );
undi->flags &= ~UNDI_FL_STARTED;
err_start_undi:
netdev_nullify ( netdev );
@ -773,22 +606,22 @@ void undinet_remove ( struct undi_device *undi ) {
/* Shut down UNDI stack */
memset ( &undi_shutdown, 0, sizeof ( undi_shutdown ) );
undinet_call ( undinic, PXENV_UNDI_SHUTDOWN, &undi_shutdown,
sizeof ( undi_shutdown ) );
pxeparent_call ( undinet_entry, PXENV_UNDI_SHUTDOWN,
&undi_shutdown, sizeof ( undi_shutdown ) );
memset ( &undi_cleanup, 0, sizeof ( undi_cleanup ) );
undinet_call ( undinic, PXENV_UNDI_CLEANUP, &undi_cleanup,
sizeof ( undi_cleanup ) );
pxeparent_call ( undinet_entry, PXENV_UNDI_CLEANUP,
&undi_cleanup, sizeof ( undi_cleanup ) );
undi->flags &= ~UNDI_FL_INITIALIZED;
/* Unhook UNDI stack */
memset ( &stop_undi, 0, sizeof ( stop_undi ) );
undinet_call ( undinic, PXENV_STOP_UNDI, &stop_undi,
sizeof ( stop_undi ) );
pxeparent_call ( undinet_entry, PXENV_STOP_UNDI, &stop_undi,
sizeof ( stop_undi ) );
undi->flags &= ~UNDI_FL_STARTED;
}
/* Clear entry point */
memset ( &undinet_entry_point, 0, sizeof ( undinet_entry_point ) );
memset ( &undinet_entry, 0, sizeof ( undinet_entry ) );
/* Free network device */
netdev_nullify ( netdev );

1
src/arch/i386/include/bits/errfile.h
View File

@ -14,6 +14,7 @@ FILE_LICENCE ( GPL2_OR_LATER );
#define ERRFILE_bios_smbios ( ERRFILE_ARCH | ERRFILE_CORE | 0x00030000 )
#define ERRFILE_biosint ( ERRFILE_ARCH | ERRFILE_CORE | 0x00040000 )
#define ERRFILE_int13 ( ERRFILE_ARCH | ERRFILE_CORE | 0x00050000 )
#define ERRFILE_pxeparent ( ERRFILE_ARCH | ERRFILE_CORE | 0x00060000 )
#define ERRFILE_bootsector ( ERRFILE_ARCH | ERRFILE_IMAGE | 0x00000000 )
#define ERRFILE_bzimage ( ERRFILE_ARCH | ERRFILE_IMAGE | 0x00010000 )

11
src/arch/i386/include/pxeparent.h Normal file
View File

@ -0,0 +1,11 @@
#ifndef PXEPARENT_H
#define PXEPARENT_H
FILE_LICENCE ( GPL2_OR_LATER );
#include <pxe_types.h>
extern int pxeparent_call ( SEGOFF16_t entry, unsigned int function,
void *params, size_t params_len );
#endif

201
src/arch/i386/interface/pxeparent/pxeparent.c Normal file
View File

@ -0,0 +1,201 @@
/*
* Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
FILE_LICENCE ( GPL2_OR_LATER );
#include <gpxe/dhcp.h>
#include <pxeparent.h>
#include <pxe_api.h>
#include <pxe_types.h>
#include <pxe.h>
/** @file
*
* Call interface to parent PXE stack
*
*/
/**
* Name PXE API call
*
* @v function API call number
* @ret name API call name
*/
static inline __attribute__ (( always_inline )) const char *
pxeparent_function_name ( unsigned int function ) {
switch ( function ) {
case PXENV_START_UNDI:
return "PXENV_START_UNDI";
case PXENV_STOP_UNDI:
return "PXENV_STOP_UNDI";
case PXENV_UNDI_STARTUP:
return "PXENV_UNDI_STARTUP";
case PXENV_UNDI_CLEANUP:
return "PXENV_UNDI_CLEANUP";
case PXENV_UNDI_INITIALIZE:
return "PXENV_UNDI_INITIALIZE";
case PXENV_UNDI_RESET_ADAPTER:
return "PXENV_UNDI_RESET_ADAPTER";
case PXENV_UNDI_SHUTDOWN:
return "PXENV_UNDI_SHUTDOWN";
case PXENV_UNDI_OPEN:
return "PXENV_UNDI_OPEN";
case PXENV_UNDI_CLOSE:
return "PXENV_UNDI_CLOSE";
case PXENV_UNDI_TRANSMIT:
return "PXENV_UNDI_TRANSMIT";
case PXENV_UNDI_SET_MCAST_ADDRESS:
return "PXENV_UNDI_SET_MCAST_ADDRESS";
case PXENV_UNDI_SET_STATION_ADDRESS:
return "PXENV_UNDI_SET_STATION_ADDRESS";
case PXENV_UNDI_SET_PACKET_FILTER:
return "PXENV_UNDI_SET_PACKET_FILTER";
case PXENV_UNDI_GET_INFORMATION:
return "PXENV_UNDI_GET_INFORMATION";
case PXENV_UNDI_GET_STATISTICS:
return "PXENV_UNDI_GET_STATISTICS";
case PXENV_UNDI_CLEAR_STATISTICS:
return "PXENV_UNDI_CLEAR_STATISTICS";
case PXENV_UNDI_INITIATE_DIAGS:
return "PXENV_UNDI_INITIATE_DIAGS";
case PXENV_UNDI_FORCE_INTERRUPT:
return "PXENV_UNDI_FORCE_INTERRUPT";
case PXENV_UNDI_GET_MCAST_ADDRESS:
return "PXENV_UNDI_GET_MCAST_ADDRESS";
case PXENV_UNDI_GET_NIC_TYPE:
return "PXENV_UNDI_GET_NIC_TYPE";
case PXENV_UNDI_GET_IFACE_INFO:
return "PXENV_UNDI_GET_IFACE_INFO";
/*
* Duplicate case value; this is a bug in the PXE specification.
*
* case PXENV_UNDI_GET_STATE:
* return "PXENV_UNDI_GET_STATE";
*/
case PXENV_UNDI_ISR:
return "PXENV_UNDI_ISR";
case PXENV_GET_CACHED_INFO:
return "PXENV_GET_CACHED_INFO";
default:
return "UNKNOWN API CALL";
}
}
/**
* PXE parent parameter block
*
* Used as the paramter block for all parent PXE API calls. Resides in base
* memory.
*/
static union u_PXENV_ANY __bss16 ( pxeparent_params );
#define pxeparent_params __use_data16 ( pxeparent_params )
/** PXE parent entry point
*
* Used as the indirection vector for all parent PXE API calls. Resides in
* base memory.
*/
SEGOFF16_t __bss16 ( pxeparent_entry_point );
#define pxeparent_entry_point __use_data16 ( pxeparent_entry_point )
/**
* Issue parent PXE API call
*
* @v entry Parent PXE stack entry point
* @v function API call number
* @v params PXE parameter block
* @v params_len Length of PXE parameter block
* @ret rc Return status code
*/
int pxeparent_call ( SEGOFF16_t entry, unsigned int function,
void *params, size_t params_len ) {
PXENV_EXIT_t exit;
int discard_b, discard_D;
int rc;
/* Copy parameter block and entry point */
assert ( params_len <= sizeof ( pxeparent_params ) );
memcpy ( &pxeparent_params, params, params_len );
memcpy ( &pxeparent_entry_point, &entry, sizeof ( entry ) );
/* Call real-mode entry point. This calling convention will
* work with both the !PXE and the PXENV+ entry points.
*/
__asm__ __volatile__ ( REAL_CODE ( "pushw %%es\n\t"
"pushw %%di\n\t"
"pushw %%bx\n\t"
"lcall *pxeparent_entry_point\n\t"
"addw $6, %%sp\n\t" )
: "=a" ( exit ), "=b" ( discard_b ),
"=D" ( discard_D )
: "b" ( function ),
"D" ( __from_data16 ( &pxeparent_params ) )
: "ecx", "edx", "esi", "ebp" );
/* PXE API calls may rudely change the status of A20 and not
* bother to restore it afterwards. Intel is known to be
* guilty of this.
*
* Note that we will return to this point even if A20 gets
* screwed up by the parent PXE stack, because Etherboot always
* resides in an even megabyte of RAM.
*/
gateA20_set();
/* Determine return status code based on PXENV_EXIT and
* PXENV_STATUS
*/
if ( exit == PXENV_EXIT_SUCCESS ) {
rc = 0;
} else {
rc = -pxeparent_params.Status;
/* Paranoia; don't return success for the combination
* of PXENV_EXIT_FAILURE but PXENV_STATUS_SUCCESS
*/
if ( rc == 0 )
rc = -EIO;
}
/* If anything goes wrong, print as much debug information as
* it's possible to give.
*/
if ( rc != 0 ) {
SEGOFF16_t rm_params = {
.segment = rm_ds,
.offset = __from_data16 ( &pxeparent_params ),
};
DBG ( "PXEPARENT %s failed: %s\n",
pxeparent_function_name ( function ), strerror ( rc ) );
DBG ( "PXEPARENT parameters at %04x:%04x length "
"%#02zx, entry point at %04x:%04x\n",
rm_params.segment, rm_params.offset, params_len,
pxeparent_entry_point.segment,
pxeparent_entry_point.offset );
DBG ( "PXEPARENT parameters provided:\n" );
DBG_HDA ( rm_params, params, params_len );
DBG ( "PXEPARENT parameters returned:\n" );
DBG_HDA ( rm_params, &pxeparent_params, params_len );
}
/* Copy parameter block back */
memcpy ( params, &pxeparent_params, params_len );
return rc;
}