actual file

diff --git a/loader/mips/linux.c b/loader/mips/linux.c
new file mode 100644 (file)
index 0000000..6b94304
--- /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 <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/machine/loader.h>
+#include <grub/command.h>
+#include <grub/mips/relocator.h>
+
+#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;
+\f
+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);
+}