diff options
Diffstat (limited to 'grub-core/lib/i386/relocator.c')
| -rw-r--r-- | grub-core/lib/i386/relocator.c | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/grub-core/lib/i386/relocator.c b/grub-core/lib/i386/relocator.c new file mode 100644 index 0000000..34cbe83 --- /dev/null +++ b/grub-core/lib/i386/relocator.c @@ -0,0 +1,210 @@ +/* + * 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/mm.h> +#include <grub/misc.h> + +#include <grub/types.h> +#include <grub/err.h> +#include <grub/term.h> + +#include <grub/i386/relocator.h> +#include <grub/relocator_private.h> +#include <grub/i386/relocator_private.h> +#include <grub/i386/pc/int.h> + +extern grub_uint8_t grub_relocator16_start; +extern grub_uint8_t grub_relocator16_end; +extern grub_uint16_t grub_relocator16_cs; +extern grub_uint16_t grub_relocator16_ip; +extern grub_uint16_t grub_relocator16_ds; +extern grub_uint16_t grub_relocator16_es; +extern grub_uint16_t grub_relocator16_fs; +extern grub_uint16_t grub_relocator16_gs; +extern grub_uint16_t grub_relocator16_ss; +extern grub_uint16_t grub_relocator16_sp; +extern grub_uint32_t grub_relocator16_edx; +extern grub_uint32_t grub_relocator16_ebx; +extern grub_uint32_t grub_relocator16_esi; +extern grub_uint32_t grub_relocator16_ebp; + +extern grub_uint16_t grub_relocator16_keep_a20_enabled; + +extern grub_uint8_t grub_relocator32_start; +extern grub_uint8_t grub_relocator32_end; +extern grub_uint32_t grub_relocator32_eax; +extern grub_uint32_t grub_relocator32_ebx; +extern grub_uint32_t grub_relocator32_ecx; +extern grub_uint32_t grub_relocator32_edx; +extern grub_uint32_t grub_relocator32_eip; +extern grub_uint32_t grub_relocator32_esp; +extern grub_uint32_t grub_relocator32_ebp; +extern grub_uint32_t grub_relocator32_esi; +extern grub_uint32_t grub_relocator32_edi; + +extern grub_uint8_t grub_relocator64_start; +extern grub_uint8_t grub_relocator64_end; +extern grub_uint64_t grub_relocator64_rax; +extern grub_uint64_t grub_relocator64_rbx; +extern grub_uint64_t grub_relocator64_rcx; +extern grub_uint64_t grub_relocator64_rdx; +extern grub_uint64_t grub_relocator64_rip; +extern grub_uint64_t grub_relocator64_rsp; +extern grub_uint64_t grub_relocator64_rsi; +extern grub_addr_t grub_relocator64_cr3; +extern struct grub_i386_idt grub_relocator16_idt; + +#define RELOCATOR_SIZEOF(x) (&grub_relocator##x##_end - &grub_relocator##x##_start) + +grub_err_t +grub_relocator32_boot (struct grub_relocator *rel, + struct grub_relocator32_state state, + int avoid_efi_bootservices) +{ + grub_err_t err; + void *relst; + grub_relocator_chunk_t ch; + + /* Specific memory range due to Global Descriptor Table for use by payload + that we will store in returned chunk. The address range and preference + are based on "THE LINUX/x86 BOOT PROTOCOL" specification. */ + err = grub_relocator_alloc_chunk_align_safe (rel, &ch, 0x1000, 0x9a000, + RELOCATOR_SIZEOF (32), 16, + GRUB_RELOCATOR_PREFERENCE_LOW, + avoid_efi_bootservices); + if (err) + return err; + + grub_relocator32_eax = state.eax; + grub_relocator32_ebx = state.ebx; + grub_relocator32_ecx = state.ecx; + grub_relocator32_edx = state.edx; + grub_relocator32_eip = state.eip; + grub_relocator32_esp = state.esp; + grub_relocator32_ebp = state.ebp; + grub_relocator32_esi = state.esi; + grub_relocator32_edi = state.edi; + + grub_memmove (get_virtual_current_address (ch), &grub_relocator32_start, + RELOCATOR_SIZEOF (32)); + + err = grub_relocator_prepare_relocs (rel, get_physical_target_address (ch), + &relst, NULL); + if (err) + return err; + + asm volatile ("cli"); + ((void (*) (void)) relst) (); + + /* Not reached. */ + return GRUB_ERR_NONE; +} + +grub_err_t +grub_relocator16_boot (struct grub_relocator *rel, + struct grub_relocator16_state state) +{ + grub_err_t err; + void *relst; + grub_relocator_chunk_t ch; + + /* Put it higher than the byte it checks for A20 check. */ + err = grub_relocator_alloc_chunk_align_safe (rel, &ch, 0x8010, 0xa0000, + RELOCATOR_SIZEOF (16) + + GRUB_RELOCATOR16_STACK_SIZE, 16, + GRUB_RELOCATOR_PREFERENCE_NONE, 0); + if (err) + return err; + + grub_relocator16_cs = state.cs; + grub_relocator16_ip = state.ip; + + grub_relocator16_ds = state.ds; + grub_relocator16_es = state.es; + grub_relocator16_fs = state.fs; + grub_relocator16_gs = state.gs; + + grub_relocator16_ss = state.ss; + grub_relocator16_sp = state.sp; + + grub_relocator16_ebp = state.ebp; + grub_relocator16_ebx = state.ebx; + grub_relocator16_edx = state.edx; + grub_relocator16_esi = state.esi; +#ifdef GRUB_MACHINE_PCBIOS + grub_relocator16_idt = *grub_realidt; +#else + grub_relocator16_idt.base = 0; + grub_relocator16_idt.limit = 0; +#endif + + grub_relocator16_keep_a20_enabled = state.a20; + + grub_memmove (get_virtual_current_address (ch), &grub_relocator16_start, + RELOCATOR_SIZEOF (16)); + + err = grub_relocator_prepare_relocs (rel, get_physical_target_address (ch), + &relst, NULL); + if (err) + return err; + + asm volatile ("cli"); + ((void (*) (void)) relst) (); + + /* Not reached. */ + return GRUB_ERR_NONE; +} + +grub_err_t +grub_relocator64_boot (struct grub_relocator *rel, + struct grub_relocator64_state state, + grub_addr_t min_addr, grub_addr_t max_addr) +{ + grub_err_t err; + void *relst; + grub_relocator_chunk_t ch; + + err = grub_relocator_alloc_chunk_align_safe (rel, &ch, min_addr, max_addr, + RELOCATOR_SIZEOF (64), 16, + GRUB_RELOCATOR_PREFERENCE_NONE, 0); + if (err) + return err; + + grub_relocator64_rax = state.rax; + grub_relocator64_rbx = state.rbx; + grub_relocator64_rcx = state.rcx; + grub_relocator64_rdx = state.rdx; + grub_relocator64_rip = state.rip; + grub_relocator64_rsp = state.rsp; + grub_relocator64_rsi = state.rsi; + grub_relocator64_cr3 = state.cr3; + + grub_memmove (get_virtual_current_address (ch), &grub_relocator64_start, + RELOCATOR_SIZEOF (64)); + + err = grub_relocator_prepare_relocs (rel, get_physical_target_address (ch), + &relst, NULL); + if (err) + return err; + + asm volatile ("cli"); + ((void (*) (void)) relst) (); + + /* Not reached. */ + return GRUB_ERR_NONE; +} |