diff options
Diffstat (limited to 'grub-core/mmap/i386/pc/mmap_helper.S')
| -rw-r--r-- | grub-core/mmap/i386/pc/mmap_helper.S | 163 |
1 files changed, 163 insertions, 0 deletions
diff --git a/grub-core/mmap/i386/pc/mmap_helper.S b/grub-core/mmap/i386/pc/mmap_helper.S new file mode 100644 index 0000000..8e251a1 --- /dev/null +++ b/grub-core/mmap/i386/pc/mmap_helper.S @@ -0,0 +1,163 @@ +/* Mmap management. */ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 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 DS(x) ((x) - LOCAL (segstart)) + +LOCAL (segstart): +VARIABLE(grub_machine_mmaphook_start) + .code16 +VARIABLE(grub_machine_mmaphook_int12) + push %ds + push %cs + pop %ds +#ifdef __APPLE__ + LOCAL(kblow_offset) = DS (LOCAL (kblow)) + movw LOCAL(kblow_offset), %ax +#else + movw DS (LOCAL (kblow)), %ax +#endif + pop %ds + iret + +VARIABLE(grub_machine_mmaphook_int15) + pushf + cmpw $0xe801, %ax + jz LOCAL (e801) + cmpw $0xe820, %ax + jz LOCAL (e820) + cmpb $0x88, %ah + jz LOCAL (h88) + popf + /* ljmp */ + .byte 0xea +VARIABLE (grub_machine_mmaphook_int15offset) + .word 0 +VARIABLE (grub_machine_mmaphook_int15segment) + .word 0 + +LOCAL (e801): + popf + push %ds + push %cs + pop %ds +#ifdef __APPLE__ + LOCAL(kbin16mb_offset) = DS (LOCAL (kbin16mb)) + LOCAL(m64kbin4gb_offset) = DS (LOCAL (m64kbin4gb)) + movw LOCAL(kbin16mb_offset), %ax + movw LOCAL(m64kbin4gb_offset), %bx +#else + movw DS (LOCAL (kbin16mb)), %ax + movw DS (LOCAL (m64kbin4gb)), %bx +#endif + movw %ax, %cx + movw %bx, %dx + pop %ds + clc + jmp LOCAL (iret_cf) + +LOCAL (h88): + popf + push %ds + push %cs + pop %ds +#ifdef __APPLE__ + movw LOCAL(kbin16mb_offset), %ax +#else + movw DS (LOCAL (kbin16mb)), %ax +#endif + pop %ds + clc + jmp LOCAL (iret_cf) + +LOCAL (e820): + popf + push %ds + push %cs + pop %ds + cmpw $20, %cx + jb LOCAL (errexit) +#ifdef __APPLE__ + LOCAL(mmap_num_offset) = DS (LOCAL (mmap_num)) + cmpw LOCAL(mmap_num_offset), %bx +#else + cmpw DS (LOCAL (mmap_num)), %bx +#endif + jae LOCAL (errexit) + cmp $0x534d4150, %edx + jne LOCAL (errexit) + push %si + push %di + movw $20, %cx +#ifdef __APPLE__ + LOCAL(mmaphook_map_offset) = DS(LOCAL (mmaphook_mmap)) + movw $LOCAL(mmaphook_map_offset), %si +#else + movw $(DS(LOCAL (mmaphook_mmap))), %si +#endif + mov %bx, %ax + imul $20, %ax + add %ax, %si + rep movsb + pop %di + pop %si + movl $20, %ecx + inc %bx +#ifdef __APPLE__ + cmpw LOCAL(mmap_num_offset), %bx +#else + cmpw DS(LOCAL (mmap_num)), %bx +#endif + jb LOCAL (noclean) + xor %bx, %bx +LOCAL (noclean): + mov $0x534d4150, %eax + pop %ds + clc + jmp LOCAL (iret_cf) +LOCAL (errexit): + mov $0x534d4150, %eax + pop %ds + xor %bx, %bx + stc + +LOCAL (iret_cf): + push %bp + mov %sp, %bp + setc 6(%bp) + pop %bp + iret + +VARIABLE(grub_machine_mmaphook_mmap_num) +LOCAL (mmap_num): + .word 0 +VARIABLE(grub_machine_mmaphook_kblow) +LOCAL (kblow): + .word 0 +VARIABLE (grub_machine_mmaphook_kbin16mb) +LOCAL (kbin16mb): + .word 0 +VARIABLE (grub_machine_mmaphook_64kbin4gb) +LOCAL (m64kbin4gb): + .word 0 +LOCAL (mmaphook_mmap): + /* Memory map is placed just after the interrupt handlers. */ +VARIABLE(grub_machine_mmaphook_end) + .byte 0 |