grub/commands/i386/pc/drivemap_int13h.S
phcoder 63963d17d0 2009-06-11 Vladimir Serbinenko <phcoder@gmail.com>
Drivemap fixes

	* commands/i386/pc/drivemap.c (grub_get_root_biosnumber_drivemap):
	new function
	(grub_get_root_biosnumber_saved): new variable
	(GRUB_MOD_INIT): register grub_get_root_biosnumber_drivemap
	(GRUB_MOD_FINI): unregister grub_get_root_biosnumber_drivemap
	* commands/i386/pc/drivemap_int13h.S (grub_drivemap_handler): restore 
	%dx after the call if necessary
	* conf/common.rmk (pkglib_MODULES): remove boot.mod
	(boot_mod_SOURCES): remove
	(boot_mod_CFLAGS): remove
	(boot_mod_LDFLAGS): remove
	* conf/i386-coreboot.rmk (pkglib_MODULES): add boot.mod
	(boot_mod_SOURCES): new variable
	(boot_mod_CFLAGS): likewise
	(boot_mod_LDFLAGS): likewise
	* conf/i386-efi.rmk: likewise
	* conf/i386-ieee1275.rmk: likewise
	* conf/i386-pc.rmk: likewise
	* conf/powerpc-ieee1275.rmk: likewise
	* conf/sparc64-ieee1275.rmk: likewise
	* conf/x86_64-efi.rmk: likewise
	* include/grub/i386/pc/biosnum.h: new file
	* lib/i386/pc/biosnum.c: likewise
	* loader/i386/bsd.c (grub_bsd_get_device): use grub_get_root_biosnumber
	* loader/i386/multiboot.c (grub_multiboot_get_bootdev): likewise
	* loader/i386/pc/chainloader.c (grub_chainloader_cmd): likewise
2009-06-11 16:13:39 +00:00

109 lines
2.6 KiB
ArmAsm

/* drivemap_int13h.S - interrupt handler for the BIOS drive remapper */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2008, 2009 Free Software Foundation, Inc.
*
* GRUB 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 3 of the License, or
* (at your option) any later version.
*
* GRUB 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 GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/symbol.h>
#define INT13H_OFFSET(x) ((x) - EXT_C(grub_drivemap_handler))
.code16
/* Copy starts here. When deployed, this code must be segment-aligned. */
/* The replacement int13 handler. Preserve all registers. */
FUNCTION(grub_drivemap_handler)
/* Save %dx for future restore. */
push %dx
/* Push flags. Used to simulate interrupt with original flags. */
pushf
/* Map the drive number (always in DL). */
push %ax
push %bx
#ifdef APPLE_CC
grub_drivemap_mapstart_ofs = INT13H_OFFSET(EXT_C(grub_drivemap_mapstart))
movw $grub_drivemap_mapstart_ofs, %bx
#else
movw $INT13H_OFFSET(EXT_C(grub_drivemap_mapstart)), %bx
#endif
more_remaining:
movw %cs:(%bx), %ax
cmpb %ah, %al
jz not_found /* DRV=DST => map end - drive not remapped, keep DL. */
inc %bx
inc %bx
cmpb %dl, %al
jnz more_remaining /* Not found, but more remaining, loop. */
movb %ah, %dl /* Found - drive remapped, modify DL. */
not_found:
pop %bx
pop %ax
cmpb $0x8, %ah
jz norestore
cmpb $0x15, %ah
jz norestore
/* Restore flags. */
popf
pushf
lcall *%cs:INT13H_OFFSET (EXT_C (grub_drivemap_oldhandler))
push %bp
mov %sp, %bp
tail:
pushf
pop %dx
mov %dx, 8(%bp)
pop %bp
/* Restore %dx. */
pop %dx
iret
norestore:
/* Restore flags. */
popf
pushf
lcall *%cs:INT13H_OFFSET (EXT_C (grub_drivemap_oldhandler))
push %bp
mov %sp, %bp
/* Save %dx. */
mov %dx, 2(%bp)
jmp tail
/* Far pointer to the old handler. Stored as a CS:IP in the style of real-mode
IVT entries (thus PI:SC in mem). */
VARIABLE(grub_drivemap_oldhandler)
.word 0x0, 0x0
/* This label MUST be at the end of the copied block, since the installer code
reserves additional space for mappings at runtime and copies them over it. */
.align 2
VARIABLE(grub_drivemap_mapstart)