From ea818634b5c283698b28eb03c76c602a0048e4fd Mon Sep 17 00:00:00 2001 From: phcoder Date: Fri, 16 Oct 2009 18:13:18 +0200 Subject: [PATCH] actual file --- loader/mips/linux.c | 317 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 317 insertions(+) create mode 100644 loader/mips/linux.c diff --git a/loader/mips/linux.c b/loader/mips/linux.c new file mode 100644 index 000000000..6b94304a5 --- /dev/null +++ b/loader/mips/linux.c @@ -0,0 +1,317 @@ +/* linux.c - boot Linux */ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2003, 2004, 2005, 2007, 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 . + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define ELF32_LOADMASK (0x00000000UL) +#define ELF64_LOADMASK (0x0000000000000000ULL) + +static grub_dl_t my_mod; + +static int loaded; + +static grub_size_t initrd_size; +static grub_size_t linux_size; + +static char *linux_args; + +static grub_uint8_t *playground; +static grub_addr_t target_addr, entry_addr, initrd_addr, args_addr; + +static grub_err_t +grub_linux_boot (void) +{ + grub_ssize_t actual; + struct grub_relocator32_state state; + + /* Boot the kernel. */ + state.gpr[1] = entry_addr; + state.jumpreg = 1; + grub_relocator32_boot (playground, target_addr, state); + + return GRUB_ERR_NONE; +} + +static grub_err_t +grub_linux_release_mem (void) +{ + grub_relocator32_free (playground); + + return GRUB_ERR_NONE; +} + +static grub_err_t +grub_linux_unload (void) +{ + grub_err_t err; + + err = grub_linux_release_mem (); + grub_dl_unref (my_mod); + + loaded = 0; + + return err; +} + +static grub_err_t +grub_linux_load32 (grub_elf_t elf, char *args) +{ + Elf32_Addr base; + int found_addr = 0; + int argsoff; + + /* Linux's entry point incorrectly contains a virtual address. */ + entry_addr = elf->ehdr.ehdr32.e_entry & ~ELF32_LOADMASK; + + linux_size = grub_elf32_size (elf, &base); + if (linux_size == 0) + return grub_errno; + target_addr = base; + /* Pad it; the kernel scribbles over memory beyond its load address. */ + linux_size += 0x100000; + argsoff = linux_size; + args_addr = target_addr + argsoff; + linux_size += grub_strlen (args) + 1; + + playground = grub_relocator32_alloc (linux_size); + if (!playground) + return grub_errno; + + grub_memcpy (playground + argsoff, args, grub_strlen (args) + 1); + + /* Now load the segments into the area we claimed. */ + auto grub_err_t offset_phdr (Elf32_Phdr *phdr, grub_addr_t *addr, int *do_load); + grub_err_t offset_phdr (Elf32_Phdr *phdr, grub_addr_t *addr, int *do_load) + { + if (phdr->p_type != PT_LOAD) + { + *do_load = 0; + return 0; + } + *do_load = 1; + + /* Linux's program headers incorrectly contain virtual addresses. + * Translate those to physical, and offset to the area we claimed. */ + *addr = phdr->p_paddr - base + playground; + return 0; + } + return grub_elf32_load (elf, offset_phdr, 0, 0); +} + +static grub_err_t +grub_linux_load64 (grub_elf_t elf) +{ + Elf64_Addr base; + int found_addr = 0; + int argsoff; + + /* Linux's entry point incorrectly contains a virtual address. */ + entry_addr = elf->ehdr.ehdr64.e_entry & ~ELF64_LOADMASK; + + linux_size = grub_elf64_size (elf, &base); + if (linux_size == 0) + return grub_errno; + target_addr = base; + /* Pad it; the kernel scribbles over memory beyond its load address. */ + linux_size += 0x100000; + argsoff = linux_size; + args_addr = target_addr + argsoff; + linux_size += grub_strlen (args) + 1; + + playground = grub_relocator32_alloc (linux_size); + if (!playground) + return grub_errno; + + grub_memcpy (playground + argsoff, args, grub_strlen (args) + 1); + + /* Now load the segments into the area we claimed. */ + auto grub_err_t offset_phdr (Elf64_Phdr *phdr, grub_addr_t *addr, int *do_load); + grub_err_t offset_phdr (Elf64_Phdr *phdr, grub_addr_t *addr, int *do_load) + { + if (phdr->p_type != PT_LOAD) + { + *do_load = 0; + return 0; + } + *do_load = 1; + /* Linux's program headers incorrectly contain virtual addresses. + * Translate those to physical, and offset to the area we claimed. */ + *addr = phdr->p_paddr - base + playground; + return 0; + } + return grub_elf64_load (elf, offset_phdr, 0, 0); +} + +static grub_err_t +grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)), + int argc, char *argv[]) +{ + grub_elf_t elf = 0; + int i; + int size; + char *dest; + + grub_dl_ref (my_mod); + + if (argc == 0) + { + grub_error (GRUB_ERR_BAD_ARGUMENT, "no kernel specified"); + goto out; + } + + elf = grub_elf_open (argv[0]); + if (! elf) + goto out; + + if (elf->ehdr.ehdr32.e_type != ET_EXEC) + { + grub_error (GRUB_ERR_UNKNOWN_OS, + "This ELF file is not of the right type\n"); + goto out; + } + + /* Release the previously used memory. */ + grub_loader_unset (); + + size = sizeof ("BOOT_IMAGE=") + grub_strlen (argv[0]); + for (i = 0; i < argc; i++) + size += grub_strlen (argv[i]) + 1; + + linux_args = grub_malloc (size); + if (! linux_args) + goto out; + + /* Specify the boot file. */ + dest = grub_stpcpy (linux_args, "BOOT_IMAGE="); + dest = grub_stpcpy (dest, argv[0]); + + for (i = 1; i < argc; i++) + { + *dest++ = ' '; + dest = grub_stpcpy (dest, argv[i]); + } + + if (grub_elf_is_elf32 (elf)) + grub_linux_load32 (elf, linux_args); + else + if (grub_elf_is_elf64 (elf)) + grub_linux_load64 (elf, linux_args); + else + { + grub_error (GRUB_ERR_BAD_FILE_TYPE, "Unknown ELF class"); + goto out; + } + +out: + + if (elf) + grub_elf_close (elf); + + if (grub_errno != GRUB_ERR_NONE) + { + grub_linux_release_mem (); + grub_dl_unref (my_mod); + loaded = 0; + } + else + { + grub_loader_set (grub_linux_boot, grub_linux_unload, 1); + initrd_addr = 0; + loaded = 1; + } + + return grub_errno; +} + +static grub_err_t +grub_cmd_initrd (grub_command_t cmd __attribute__ ((unused)), + int argc, char *argv[]) +{ + grub_file_t file = 0; + grub_ssize_t size; + grub_addr_t addr; + int found_addr = 0; + + if (argc == 0) + { + grub_error (GRUB_ERR_BAD_ARGUMENT, "no initrd specified"); + goto fail; + } + + if (!loaded) + { + grub_error (GRUB_ERR_BAD_ARGUMENT, "You need to load the kernel first."); + goto fail; + } + + file = grub_file_open (argv[0]); + if (! file) + return grub_errno; + + size = grub_file_size (file); + + playground = grub_relocator32_realloc (playground, linux_size + size); + if (!playground) + { + grub_file_close (file); + return grub_errno; + } + + grub_dprintf ("loader", "Loading initrd at 0x%x, size 0x%x\n", addr, size); + + if (grub_file_read (file, playground + linux_size, size) != size) + { + grub_error (GRUB_ERR_FILE_READ_ERROR, "Couldn't read file"); + grub_file_close (file); + + return grub_errno; + } + + initrd_addr = target_addr + linux_size; + initrd_size = size; + + grub_file_close (file); + + return GRUB_ERR_NONE; +} + +static grub_command_t cmd_linux, cmd_initrd; + +GRUB_MOD_INIT(linux) +{ + cmd_linux = grub_register_command ("linux", grub_cmd_linux, + 0, "load a linux kernel"); + cmd_initrd = grub_register_command ("initrd", grub_cmd_initrd, + 0, "load an initrd"); + my_mod = mod; +} + +GRUB_MOD_FINI(linux) +{ + grub_unregister_command (cmd_linux); + grub_unregister_command (cmd_initrd); +}