/* 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 <http://www.gnu.org/licenses/>.
*/
#include <grub/elf.h>
#include <grub/elfload.h>
#include <grub/loader.h>
#include <grub/dl.h>
#include <grub/mm.h>
#include <grub/misc.h>
#include <grub/ieee1275/ieee1275.h>
#include <grub/command.h>
#include <grub/i18n.h>
#include <grub/memory.h>
#include <grub/lib/cmdline.h>
#include <grub/cache.h>
GRUB_MOD_LICENSE ("GPLv3+");
#define ELF32_LOADMASK (0xc0000000UL)
#define ELF64_LOADMASK (0xc000000000000000ULL)
static grub_dl_t my_mod;
static int loaded;
static grub_addr_t initrd_addr;
static grub_size_t initrd_size;
static grub_addr_t linux_addr;
static grub_addr_t linux_entry;
static grub_size_t linux_size;
static char *linux_args;
typedef void (*kernel_entry_t) (void *, unsigned long, int (void *),
unsigned long, unsigned long);
/* Helper for grub_linux_claimmap_iterate. */
static int
alloc_mem (grub_uint64_t addr, grub_uint64_t len, grub_memory_type_t type,
void *data)
{
grub_addr_t *found_addr = data;
grub_uint64_t end = addr + len;
addr = ALIGN_UP (addr, align);
target = ALIGN_UP (target, align);
/* Target above the memory chunk. */
if (type != GRUB_MEMORY_AVAILABLE || target > end)
return 0;
/* Target inside the memory chunk. */
if (target >= addr && target < end && size <= end - target)
{
if (grub_claimmap (target, size) == GRUB_ERR_NONE)
{
*found_addr = target;
return 1;
}
grub_print_error ();
}
/* Target below the memory chunk. */
if (target < addr && addr + size <= end)
{
if (grub_claimmap (addr, size) == GRUB_ERR_NONE)
{
*found_addr = addr;
return 1;
}
grub_print_error ();
}
return 0;
}
static grub_addr_t
grub_linux_claimmap_iterate (grub_addr_t target, grub_size_t size,
grub_size_t align)
{
grub_addr_t found_addr = (grub_addr_t) -1;
grub_machine_mmap_iterate (alloc_mem, &found_addr);
return found_addr;
}
static grub_err_t
grub_linux_boot (void)
{
kernel_entry_t linuxmain;
grub_ssize_t actual;
grub_arch_sync_caches ((void *) linux_addr, linux_size);
/* Set the command line arguments. */
grub_ieee1275_set_property (grub_ieee1275_chosen, "bootargs", linux_args,
grub_strlen (linux_args) + 1, &actual);
grub_dprintf ("loader", "Entry point: 0x%x\n", linux_entry);
grub_dprintf ("loader", "Initrd at: 0x%x, size 0x%x\n", initrd_addr,
initrd_size);
grub_dprintf ("loader", "Boot arguments: %s\n", linux_args);
grub_dprintf ("loader", "Jumping to Linux...\n");
/* Boot the kernel. */
linuxmain = (kernel_entry_t) linux_entry;
linuxmain ((void *) initrd_addr, initrd_size, grub_ieee1275_entry_fn, 0, 0);
return GRUB_ERR_NONE;
}
static grub_err_t
grub_linux_release_mem (void)
{
grub_free (linux_args);
linux_args = 0;
if (linux_addr && grub_ieee1275_release (linux_addr, linux_size))
return grub_error (GRUB_ERR_OUT_OF_MEMORY, "cannot release memory");
if (initrd_addr && grub_ieee1275_release (initrd_addr, initrd_size))
return grub_error (GRUB_ERR_OUT_OF_MEMORY, "cannot release memory");
linux_addr = 0;
initrd_addr = 0;
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, const char *filename)
{
Elf32_Addr base_addr;
grub_addr_t seg_addr;
grub_uint32_t align;
grub_uint32_t offset;
Elf32_Addr entry;
linux_size = grub_elf32_size (elf, filename, &base_addr, &align);
if (linux_size == 0)
return grub_errno;
/* Pad it; the kernel scribbles over memory beyond its load address. */
linux_size += 0x100000;
/* Linux's entry point incorrectly contains a virtual address. */
entry = elf->ehdr.ehdr32.e_entry & ~ELF32_LOADMASK;
/* Linux's incorrectly contains a virtual address. */
base_addr &= ~ELF32_LOADMASK;
offset = entry - base_addr;
/* On some systems, firmware occupies the memory we're trying to use.
* Happily, Linux can be loaded anywhere (it relocates itself). Iterate
* until we find an open area. */
seg_addr = grub_linux_claimmap_iterate (base_addr & ~ELF32_LOADMASK, linux_size, align);
if (seg_addr == (grub_addr_t) -1)
return grub_error (GRUB_ERR_OUT_OF_MEMORY, "couldn't claim memory");
linux_entry = seg_addr + offset;
linux_addr = seg_addr;
/* 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;
*addr = (phdr->p_paddr - base_addr) + seg_addr;
return 0;
}
return grub_elf32_load (elf, filename, offset_phdr, 0, 0);
}
static grub_err_t
grub_linux_load64 (grub_elf_t elf, const char *filename)
{
Elf64_Addr base_addr;
grub_addr_t seg_addr;
grub_uint64_t align;
grub_uint64_t offset;
Elf64_Addr entry;
linux_size = grub_elf64_size (elf, filename, &base_addr, &align);
if (linux_size == 0)
return grub_errno;
/* Pad it; the kernel scribbles over memory beyond its load address. */
linux_size += 0x100000;
base_addr &= ~ELF64_LOADMASK;
entry = elf->ehdr.ehdr64.e_entry & ~ELF64_LOADMASK;
offset = entry - base_addr;
/* Linux's incorrectly contains a virtual address. */
/* On some systems, firmware occupies the memory we're trying to use.
* Happily, Linux can be loaded anywhere (it relocates itself). Iterate
* until we find an open area. */
seg_addr = grub_linux_claimmap_iterate (base_addr & ~ELF64_LOADMASK, linux_size, align);
if (seg_addr == (grub_addr_t) -1)
return grub_error (GRUB_ERR_OUT_OF_MEMORY, "couldn't claim memory");
linux_entry = seg_addr + offset;
linux_addr = seg_addr;
/* 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;
*addr = (phdr->p_paddr - base_addr) + seg_addr;
return 0;
}
return grub_elf64_load (elf, filename, 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 size;
grub_dl_ref (my_mod);
if (argc == 0)
{
grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected"));
goto out;
}
elf = grub_elf_open (argv[0]);
if (! elf)
goto out;
if (elf->ehdr.ehdr32.e_type != ET_EXEC && elf->ehdr.ehdr32.e_type != ET_DYN)
{
grub_error (GRUB_ERR_UNKNOWN_OS,
N_("this ELF file is not of the right type"));
goto out;
}
/* Release the previously used memory. */
grub_loader_unset ();
if (grub_elf_is_elf32 (elf))
grub_linux_load32 (elf, argv[0]);
else
if (grub_elf_is_elf64 (elf))
grub_linux_load64 (elf, argv[0]);
else
{
grub_error (GRUB_ERR_BAD_FILE_TYPE, N_("invalid arch-dependent ELF magic"));
goto out;
}
size = grub_loader_cmdline_size(argc, argv);
linux_args = grub_malloc (size + sizeof (LINUX_IMAGE));
if (! linux_args)
goto out;
/* Create kernel command line. */
grub_memcpy (linux_args, LINUX_IMAGE, sizeof (LINUX_IMAGE));
grub_create_loader_cmdline (argc, argv, linux_args + sizeof (LINUX_IMAGE) - 1,
size);
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 *files = 0;
grub_size_t size = 0;
grub_addr_t first_addr;
grub_addr_t addr;
int i;
int nfiles = 0;
grub_uint8_t *ptr;
if (argc == 0)
{
grub_error (GRUB_ERR_BAD_ARGUMENT, N_("filename expected"));
goto fail;
}
if (!loaded)
{
grub_error (GRUB_ERR_BAD_ARGUMENT, N_("you need to load the kernel first"));
goto fail;
}
files = grub_zalloc (argc * sizeof (files[0]));
if (!files)
goto fail;
for (i = 0; i < argc; i++)
{
grub_file_filter_disable_compression ();
files[i] = grub_file_open (argv[i]);
if (! files[i])
goto fail;
nfiles++;
size += ALIGN_UP (grub_file_size (files[i]), 4);
}
first_addr = linux_addr + linux_size;
/* Attempt to claim at a series of addresses until successful in
the same way that grub_rescue_cmd_linux does. */
addr = grub_linux_claimmap_iterate (first_addr, size, 0x100000);
if (addr == (grub_addr_t) -1)
goto fail;
grub_dprintf ("loader", "Loading initrd at 0x%x, size 0x%x\n", addr, size);
ptr = (void *) addr;
for (i = 0; i < nfiles; i++)
{
grub_ssize_t cursize = grub_file_size (files[i]);
if (grub_file_read (files[i], ptr, cursize) != cursize)
{
grub_ieee1275_release (addr, size);
if (!grub_errno)
grub_error (GRUB_ERR_FILE_READ_ERROR, N_("premature end of file %s"),
argv[i]);
goto fail;
}
ptr += cursize;
grub_memset (ptr, 0, ALIGN_UP_OVERHEAD (cursize, 4));
ptr += ALIGN_UP_OVERHEAD (cursize, 4);
}
initrd_addr = addr;
initrd_size = size;
fail:
for (i = 0; i < nfiles; i++)
grub_file_close (files[i]);
grub_free (files);
return grub_errno;
}
static grub_command_t cmd_linux, cmd_initrd;
GRUB_MOD_INIT(linux)
{
cmd_linux = grub_register_command ("linux", grub_cmd_linux,
0, N_("Load Linux."));
cmd_initrd = grub_register_command ("initrd", grub_cmd_initrd,
0, N_("Load initrd."));
my_mod = mod;
}
GRUB_MOD_FINI(linux)
{
grub_unregister_command (cmd_linux);
grub_unregister_command (cmd_initrd);
}