/* * GRUB -- GRand Unified Bootloader * Copyright (C) 2006,2007,2008,2009 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 #include #include #include #include #include /* FIXME: the definition of `struct grub_video_render_target' is VBE-specific. */ #include #include #define GRUB_LINUX_CL_OFFSET 0x1000 #define GRUB_LINUX_CL_END_OFFSET 0x2000 static grub_dl_t my_mod; static grub_size_t linux_mem_size; static int loaded; static void *real_mode_mem; static void *prot_mode_mem; static void *initrd_mem; static grub_uint32_t real_mode_pages; static grub_uint32_t prot_mode_pages; static grub_uint32_t initrd_pages; static grub_uint8_t gdt[] __attribute__ ((aligned(16))) = { /* NULL. */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* Reserved. */ 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, /* Code segment. */ 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x9A, 0xCF, 0x00, /* Data segment. */ 0xFF, 0xFF, 0x00, 0x00, 0x00, 0x92, 0xCF, 0x00 }; struct gdt_descriptor { grub_uint16_t limit; void *base; } __attribute__ ((packed)); static struct gdt_descriptor gdt_desc = { sizeof (gdt) - 1, gdt }; struct idt_descriptor { grub_uint16_t limit; void *base; } __attribute__ ((packed)); static struct idt_descriptor idt_desc = { 0, 0 }; static grub_uint16_t vid_mode; struct linux_vesafb_res { grub_uint16_t width; grub_uint16_t height; }; enum vga_modes { VGA_640_480, VGA_800_600, VGA_1024_768, VGA_1280_1024, }; struct linux_vesafb_mode { grub_uint8_t res_index; grub_uint8_t depth; }; static struct linux_vesafb_res linux_vesafb_res[] = { { 640, 480 }, { 800, 600 }, { 1024, 768 }, { 1280, 1024 } }; /* This is the reverse of the table in [linux]/Documentation/fb/vesafb.txt. */ struct linux_vesafb_mode linux_vesafb_modes[] = { { VGA_640_480, 8 }, /* 0x301 */ { 0, 0 }, { VGA_800_600, 8 }, /* 0x303 */ { 0, 0 }, { VGA_1024_768, 8 }, /* 0x305 */ { 0, 0 }, { VGA_1280_1024, 8 }, /* 0x307 */ { 0, 0 }, { 0, 0 }, { 0, 0 }, { 0, 0 }, { 0, 0 }, { 0, 0 }, { 0, 0 }, { 0, 0 }, { VGA_640_480, 15 }, /* 0x310 */ { VGA_640_480, 16 }, /* 0x311 */ { VGA_640_480, 24 }, /* 0x312 */ { VGA_800_600, 15 }, /* 0x313 */ { VGA_800_600, 16 }, /* 0x314 */ { VGA_800_600, 24 }, /* 0x315 */ { VGA_1024_768, 15 }, /* 0x316 */ { VGA_1024_768, 16 }, /* 0x317 */ { VGA_1024_768, 24 }, /* 0x318 */ { VGA_1280_1024, 15 }, /* 0x319 */ { VGA_1280_1024, 16 }, /* 0x31a */ { VGA_1280_1024, 24 }, /* 0x31b */ }; static inline grub_size_t page_align (grub_size_t size) { return (size + (1 << 12) - 1) & (~((1 << 12) - 1)); } /* Find the optimal number of pages for the memory map. */ static grub_size_t find_mmap_size (void) { grub_size_t count = 0, mmap_size; auto int NESTED_FUNC_ATTR hook (grub_uint64_t, grub_uint64_t, grub_uint32_t); int NESTED_FUNC_ATTR hook (grub_uint64_t addr __attribute__ ((unused)), grub_uint64_t size __attribute__ ((unused)), grub_uint32_t type __attribute__ ((unused))) { count++; return 0; } grub_machine_mmap_iterate (hook); mmap_size = count * sizeof (struct grub_e820_mmap); /* Increase the size a bit for safety, because GRUB allocates more on later. */ mmap_size += (1 << 12); return page_align (mmap_size); } static void free_pages (void) { real_mode_mem = prot_mode_mem = initrd_mem = 0; } /* Allocate pages for the real mode code and the protected mode code for linux as well as a memory map buffer. */ static int allocate_pages (grub_size_t prot_size) { grub_size_t real_size, mmap_size; /* Make sure that each size is aligned to a page boundary. */ real_size = GRUB_LINUX_CL_END_OFFSET; prot_size = page_align (prot_size); mmap_size = find_mmap_size (); grub_dprintf ("linux", "real_size = %x, prot_size = %x, mmap_size = %x\n", (unsigned) real_size, (unsigned) prot_size, (unsigned) mmap_size); /* Calculate the number of pages; Combine the real mode code with the memory map buffer for simplicity. */ real_mode_pages = ((real_size + mmap_size) >> 12); prot_mode_pages = (prot_size >> 12); /* Initialize the memory pointers with NULL for convenience. */ real_mode_mem = 0; prot_mode_mem = 0; /* FIXME: Should request low memory from the heap when this feature is implemented. */ auto int NESTED_FUNC_ATTR hook (grub_uint64_t, grub_uint64_t, grub_uint32_t); int NESTED_FUNC_ATTR hook (grub_uint64_t addr, grub_uint64_t size, grub_uint32_t type) { /* We must put real mode code in the traditional space. */ if (type == GRUB_MACHINE_MEMORY_AVAILABLE && addr <= 0x90000) { if (addr < 0x10000) { size += addr - 0x10000; addr = 0x10000; } if (addr + size > 0x90000) size = 0x90000 - addr; if (real_size + mmap_size > size) return 0; real_mode_mem = (void *) ((addr + size) - (real_size + mmap_size)); return 1; } return 0; } grub_machine_mmap_iterate (hook); if (! real_mode_mem) { grub_error (GRUB_ERR_OUT_OF_MEMORY, "cannot allocate real mode pages"); goto fail; } prot_mode_mem = (void *) 0x100000; grub_dprintf ("linux", "real_mode_mem = %lx, real_mode_pages = %x, " "prot_mode_mem = %lx, prot_mode_pages = %x\n", (unsigned long) real_mode_mem, (unsigned) real_mode_pages, (unsigned long) prot_mode_mem, (unsigned) prot_mode_pages); return 1; fail: free_pages (); return 0; } static void grub_e820_add_region (struct grub_e820_mmap *e820_map, int *e820_num, grub_uint64_t start, grub_uint64_t size, grub_uint32_t type) { int n = *e820_num; if (n >= GRUB_E820_MAX_ENTRY) grub_fatal ("Too many e820 memory map entries"); if ((n > 0) && (e820_map[n - 1].addr + e820_map[n - 1].size == start) && (e820_map[n - 1].type == type)) e820_map[n - 1].size += size; else { e820_map[n].addr = start; e820_map[n].size = size; e820_map[n].type = type; (*e820_num)++; } } static int grub_linux_setup_video (struct linux_kernel_params *params) { struct grub_video_mode_info mode_info; struct grub_video_render_target *render_target; int ret; ret = grub_video_get_info (&mode_info); if (ret) return 1; ret = grub_video_get_active_render_target (&render_target); if (ret) return 1; params->lfb_width = mode_info.width; params->lfb_height = mode_info.height; params->lfb_depth = mode_info.bpp; params->lfb_line_len = mode_info.pitch; params->lfb_base = (void *) render_target->data; params->lfb_size = (params->lfb_line_len * params->lfb_height + 65535) >> 16; params->red_mask_size = mode_info.red_mask_size; params->red_field_pos = mode_info.red_field_pos; params->green_mask_size = mode_info.green_mask_size; params->green_field_pos = mode_info.green_field_pos; params->blue_mask_size = mode_info.blue_mask_size; params->blue_field_pos = mode_info.blue_field_pos; params->reserved_mask_size = mode_info.reserved_mask_size; params->reserved_field_pos = mode_info.reserved_field_pos; return 0; } #ifdef __x86_64__ struct { grub_uint32_t kernel_entry; grub_uint32_t kernel_cs; } jumpvector; #endif static grub_err_t grub_linux_boot (void) { struct linux_kernel_params *params; int e820_num; params = real_mode_mem; if (vid_mode == GRUB_LINUX_VID_MODE_NORMAL || vid_mode == GRUB_LINUX_VID_MODE_EXTENDED) grub_video_restore (); else if (vid_mode) { struct linux_vesafb_mode *linux_mode; int depth, flags; flags = 0; linux_mode = &linux_vesafb_modes[vid_mode - 0x301]; depth = linux_mode->depth; /* If we have 8 or less bits, then assume that it is indexed color mode. */ if ((depth <= 8) && (depth != -1)) flags |= GRUB_VIDEO_MODE_TYPE_INDEX_COLOR; /* We have more than 8 bits, then assume that it is RGB color mode. */ if (depth > 8) flags |= GRUB_VIDEO_MODE_TYPE_RGB; /* If user requested specific depth, forward that information to driver. */ if (depth != -1) flags |= (depth << GRUB_VIDEO_MODE_TYPE_DEPTH_POS) & GRUB_VIDEO_MODE_TYPE_DEPTH_MASK; /* Try to initialize requested mode. */ if (grub_video_setup (linux_vesafb_res[linux_mode->res_index].width, linux_vesafb_res[linux_mode->res_index].height, flags) != GRUB_ERR_NONE) { grub_printf ("Unable to initialize requested video mode (vga=0x%x)\n", vid_mode); return grub_errno; } } if (! grub_linux_setup_video (params)) params->have_vga = GRUB_VIDEO_TYPE_VLFB; else { params->have_vga = 0; params->video_cursor_x = grub_getxy () >> 8; params->video_cursor_y = grub_getxy () & 0xff; params->video_width = 80; params->video_height = 25; } grub_dprintf ("linux", "code32_start = %x, idt_desc = %lx, gdt_desc = %lx\n", (unsigned) params->code32_start, (unsigned long) &(idt_desc.limit), (unsigned long) &(gdt_desc.limit)); grub_dprintf ("linux", "idt = %x:%lx, gdt = %x:%lx\n", (unsigned) idt_desc.limit, (unsigned long) idt_desc.base, (unsigned) gdt_desc.limit, (unsigned long) gdt_desc.base); auto int NESTED_FUNC_ATTR hook (grub_uint64_t, grub_uint64_t, grub_uint32_t); int NESTED_FUNC_ATTR hook (grub_uint64_t addr, grub_uint64_t size, grub_uint32_t type) { switch (type) { case GRUB_MACHINE_MEMORY_AVAILABLE: grub_e820_add_region (params->e820_map, &e820_num, addr, size, GRUB_E820_RAM); break; default: grub_e820_add_region (params->e820_map, &e820_num, addr, size, GRUB_E820_RESERVED); } return 0; } e820_num = 0; grub_machine_mmap_iterate (hook); params->mmap_size = e820_num; /* Hardware interrupts are not safe any longer. */ asm volatile ("cli" : : ); /* Load the IDT and the GDT for the bootstrap. */ asm volatile ("lidt %0" : : "m" (idt_desc)); asm volatile ("lgdt %0" : : "m" (gdt_desc)); #ifdef __x86_64__ jumpvector.kernel_entry = (grub_uint64_t) grub_linux_real_boot; jumpvector.kernel_cs = 0x10; asm volatile ( "mov %0, %%rbx" : : "m" (params->code32_start)); asm volatile ( "mov %0, %%rsi" : : "m" (real_mode_mem)); asm volatile ( "ljmp *%0" : : "m" (jumpvector)); #else /* Pass parameters. */ asm volatile ("movl %0, %%ecx" : : "m" (params->code32_start)); asm volatile ("movl %0, %%esi" : : "m" (real_mode_mem)); asm volatile ("xorl %%ebx, %%ebx" : : ); /* Enter Linux. */ asm volatile ("jmp *%%ecx" : : ); #endif /* Never reach here. */ return GRUB_ERR_NONE; } static grub_err_t grub_linux_unload (void) { free_pages (); grub_dl_unref (my_mod); loaded = 0; return GRUB_ERR_NONE; } static grub_err_t grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)), int argc, char *argv[]) { grub_file_t file = 0; struct linux_kernel_header lh; struct linux_kernel_params *params; grub_uint8_t setup_sects; grub_size_t real_size, prot_size; grub_ssize_t len; int i; char *dest; grub_dl_ref (my_mod); if (argc == 0) { grub_error (GRUB_ERR_BAD_ARGUMENT, "no kernel specified"); goto fail; } file = grub_file_open (argv[0]); if (! file) goto fail; if (grub_file_read (file, (char *) &lh, sizeof (lh)) != sizeof (lh)) { grub_error (GRUB_ERR_READ_ERROR, "cannot read the linux header"); goto fail; } if (lh.boot_flag != grub_cpu_to_le16 (0xaa55)) { grub_error (GRUB_ERR_BAD_OS, "invalid magic number"); goto fail; } if (lh.setup_sects > GRUB_LINUX_MAX_SETUP_SECTS) { grub_error (GRUB_ERR_BAD_OS, "too many setup sectors"); goto fail; } if (! (lh.loadflags & GRUB_LINUX_FLAG_BIG_KERNEL)) { grub_error (GRUB_ERR_BAD_OS, "zImage doesn't support 32-bit boot" #ifdef GRUB_MACHINE_PCBIOS " (try with `linux16')" #endif ); goto fail; } /* FIXME: 2.03 is not always good enough (Linux 2.4 can be 2.03 and still not support 32-bit boot. */ if (lh.header != grub_cpu_to_le32 (GRUB_LINUX_MAGIC_SIGNATURE) || grub_le_to_cpu16 (lh.version) < 0x0203) { grub_error (GRUB_ERR_BAD_OS, "version too old for 32-bit boot" #ifdef GRUB_MACHINE_PCBIOS " (try with `linux16')" #endif ); goto fail; } setup_sects = lh.setup_sects; /* If SETUP_SECTS is not set, set it to the default (4). */ if (! setup_sects) setup_sects = GRUB_LINUX_DEFAULT_SETUP_SECTS; real_size = setup_sects << GRUB_DISK_SECTOR_BITS; prot_size = grub_file_size (file) - real_size - GRUB_DISK_SECTOR_SIZE; if (! allocate_pages (prot_size)) goto fail; params = (struct linux_kernel_params *) real_mode_mem; grub_memset (params, 0, GRUB_LINUX_CL_END_OFFSET); grub_memcpy (¶ms->setup_sects, &lh.setup_sects, sizeof (lh) - 0x1F1); params->ps_mouse = params->padding10 = 0; len = 0x400 - sizeof (lh); if (grub_file_read (file, (char *) real_mode_mem + sizeof (lh), len) != len) { grub_error (GRUB_ERR_FILE_READ_ERROR, "Couldn't read file"); goto fail; } params->type_of_loader = (LINUX_LOADER_ID_GRUB << 4); params->cl_magic = GRUB_LINUX_CL_MAGIC; params->cl_offset = 0x1000; params->cmd_line_ptr = (unsigned long) real_mode_mem + 0x1000; params->ramdisk_image = 0; params->ramdisk_size = 0; params->heap_end_ptr = GRUB_LINUX_HEAP_END_OFFSET; params->loadflags |= GRUB_LINUX_FLAG_CAN_USE_HEAP; /* These are not needed to be precise, because Linux uses these values only to raise an error when the decompression code cannot find good space. */ params->ext_mem = ((32 * 0x100000) >> 10); params->alt_mem = ((32 * 0x100000) >> 10); params->video_page = 0; /* ??? */ params->video_mode = 0; params->video_ega_bx = 0; params->font_size = 16; /* XXX */ /* The other parameters are filled when booting. */ grub_file_seek (file, real_size + GRUB_DISK_SECTOR_SIZE); grub_printf (" [Linux-bzImage, setup=0x%x, size=0x%x]\n", (unsigned) real_size, (unsigned) prot_size); /* Detect explicitly specified memory size, if any. */ linux_mem_size = 0; for (i = 1; i < argc; i++) if (grub_memcmp (argv[i], "vga=", 4) == 0) { /* Video mode selection support. */ char *val = argv[i] + 4; if (grub_strcmp (val, "normal") == 0) vid_mode = GRUB_LINUX_VID_MODE_NORMAL; else if (grub_strcmp (val, "ext") == 0) vid_mode = GRUB_LINUX_VID_MODE_EXTENDED; else vid_mode = (grub_uint16_t) grub_strtoul (val, 0, 0); if (grub_errno) goto fail; } else if (grub_memcmp (argv[i], "mem=", 4) == 0) { char *val = argv[i] + 4; linux_mem_size = grub_strtoul (val, &val, 0); if (grub_errno) { grub_errno = GRUB_ERR_NONE; linux_mem_size = 0; } else { int shift = 0; switch (grub_tolower (val[0])) { case 'g': shift += 10; case 'm': shift += 10; case 'k': shift += 10; default: break; } /* Check an overflow. */ if (linux_mem_size > (~0UL >> shift)) linux_mem_size = 0; else linux_mem_size <<= shift; } } /* Specify the boot file. */ dest = grub_stpcpy ((char *) real_mode_mem + GRUB_LINUX_CL_OFFSET, "BOOT_IMAGE="); dest = grub_stpcpy (dest, argv[0]); /* Copy kernel parameters. */ for (i = 1; i < argc && dest + grub_strlen (argv[i]) + 1 < ((char *) real_mode_mem + GRUB_LINUX_CL_END_OFFSET); i++) { *dest++ = ' '; dest = grub_stpcpy (dest, argv[i]); } len = prot_size; if (grub_file_read (file, (char *) GRUB_LINUX_BZIMAGE_ADDR, len) != len) grub_error (GRUB_ERR_FILE_READ_ERROR, "Couldn't read file"); if (grub_errno == GRUB_ERR_NONE) { grub_loader_set (grub_linux_boot, grub_linux_unload, 0 /* set noreturn=0 in order to avoid grub_console_fini() */); loaded = 1; } fail: if (file) grub_file_close (file); if (grub_errno != GRUB_ERR_NONE) { grub_dl_unref (my_mod); loaded = 0; } 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_min, addr_max; grub_addr_t addr; struct linux_kernel_header *lh; if (argc == 0) { grub_error (GRUB_ERR_BAD_ARGUMENT, "No module 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) goto fail; size = grub_file_size (file); initrd_pages = (page_align (size) >> 12); lh = (struct linux_kernel_header *) real_mode_mem; /* Get the highest address available for the initrd. */ if (grub_le_to_cpu16 (lh->version) >= 0x0203) { addr_max = grub_cpu_to_le32 (lh->initrd_addr_max); /* XXX in reality, Linux specifies a bogus value, so it is necessary to make sure that ADDR_MAX does not exceed 0x3fffffff. */ if (addr_max > GRUB_LINUX_INITRD_MAX_ADDRESS) addr_max = GRUB_LINUX_INITRD_MAX_ADDRESS; } else addr_max = GRUB_LINUX_INITRD_MAX_ADDRESS; if (linux_mem_size != 0 && linux_mem_size < addr_max) addr_max = linux_mem_size; /* Linux 2.3.xx has a bug in the memory range check, so avoid the last page. Linux 2.2.xx has a bug in the memory range check, which is worse than that of Linux 2.3.xx, so avoid the last 64kb. */ addr_max -= 0x10000; /* Usually, the compression ratio is about 50%. */ addr_min = (grub_addr_t) prot_mode_mem + ((prot_mode_pages * 3) << 12) + page_align (size); if (addr_max > grub_os_area_addr + grub_os_area_size) addr_max = grub_os_area_addr + grub_os_area_size; /* Put the initrd as high as possible, 4KiB aligned. */ addr = (addr_max - size) & ~0xFFF; if (addr < addr_min) { grub_error (GRUB_ERR_OUT_OF_RANGE, "The initrd is too big"); goto fail; } initrd_mem = (void *) addr; if (grub_file_read (file, initrd_mem, size) != size) { grub_error (GRUB_ERR_FILE_READ_ERROR, "Couldn't read file"); goto fail; } grub_printf (" [Initrd, addr=0x%x, size=0x%x]\n", (unsigned) addr, (unsigned) size); lh->ramdisk_image = addr; lh->ramdisk_size = size; lh->root_dev = 0x0100; /* XXX */ fail: if (file) grub_file_close (file); 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, "load linux"); cmd_initrd = grub_register_command ("initrd", grub_cmd_initrd, 0, "load initrd"); my_mod = mod; } GRUB_MOD_FINI(linux) { grub_unregister_command (cmd_linux); grub_unregister_command (cmd_initrd); }