multiboot.c (14187B)
1/* 2 * QEMU PC System Emulator 3 * 4 * Copyright (c) 2003-2004 Fabrice Bellard 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to deal 8 * in the Software without restriction, including without limitation the rights 9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 10 * copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 22 * THE SOFTWARE. 23 */ 24 25#include "qemu/osdep.h" 26#include "qemu/option.h" 27#include "cpu.h" 28#include "hw/nvram/fw_cfg.h" 29#include "multiboot.h" 30#include "hw/loader.h" 31#include "elf.h" 32#include "sysemu/sysemu.h" 33#include "qemu/error-report.h" 34 35/* Show multiboot debug output */ 36//#define DEBUG_MULTIBOOT 37 38#ifdef DEBUG_MULTIBOOT 39#define mb_debug(a...) error_report(a) 40#else 41#define mb_debug(a...) 42#endif 43 44#define MULTIBOOT_STRUCT_ADDR 0x9000 45 46#if MULTIBOOT_STRUCT_ADDR > 0xf0000 47#error multiboot struct needs to fit in 16 bit real mode 48#endif 49 50enum { 51 /* Multiboot info */ 52 MBI_FLAGS = 0, 53 MBI_MEM_LOWER = 4, 54 MBI_MEM_UPPER = 8, 55 MBI_BOOT_DEVICE = 12, 56 MBI_CMDLINE = 16, 57 MBI_MODS_COUNT = 20, 58 MBI_MODS_ADDR = 24, 59 MBI_MMAP_ADDR = 48, 60 MBI_BOOTLOADER = 64, 61 62 MBI_SIZE = 88, 63 64 /* Multiboot modules */ 65 MB_MOD_START = 0, 66 MB_MOD_END = 4, 67 MB_MOD_CMDLINE = 8, 68 69 MB_MOD_SIZE = 16, 70 71 /* Region offsets */ 72 ADDR_E820_MAP = MULTIBOOT_STRUCT_ADDR + 0, 73 ADDR_MBI = ADDR_E820_MAP + 0x500, 74 75 /* Multiboot flags */ 76 MULTIBOOT_FLAGS_MEMORY = 1 << 0, 77 MULTIBOOT_FLAGS_BOOT_DEVICE = 1 << 1, 78 MULTIBOOT_FLAGS_CMDLINE = 1 << 2, 79 MULTIBOOT_FLAGS_MODULES = 1 << 3, 80 MULTIBOOT_FLAGS_MMAP = 1 << 6, 81 MULTIBOOT_FLAGS_BOOTLOADER = 1 << 9, 82}; 83 84typedef struct { 85 /* buffer holding kernel, cmdlines and mb_infos */ 86 void *mb_buf; 87 /* address in target */ 88 hwaddr mb_buf_phys; 89 /* size of mb_buf in bytes */ 90 unsigned mb_buf_size; 91 /* offset of mb-info's in bytes */ 92 hwaddr offset_mbinfo; 93 /* offset in buffer for cmdlines in bytes */ 94 hwaddr offset_cmdlines; 95 /* offset in buffer for bootloader name in bytes */ 96 hwaddr offset_bootloader; 97 /* offset of modules in bytes */ 98 hwaddr offset_mods; 99 /* available slots for mb modules infos */ 100 int mb_mods_avail; 101 /* currently used slots of mb modules */ 102 int mb_mods_count; 103} MultibootState; 104 105const char *bootloader_name = "qemu"; 106 107static uint32_t mb_add_cmdline(MultibootState *s, const char *cmdline) 108{ 109 hwaddr p = s->offset_cmdlines; 110 char *b = (char *)s->mb_buf + p; 111 112 memcpy(b, cmdline, strlen(cmdline) + 1); 113 s->offset_cmdlines += strlen(b) + 1; 114 return s->mb_buf_phys + p; 115} 116 117static uint32_t mb_add_bootloader(MultibootState *s, const char *bootloader) 118{ 119 hwaddr p = s->offset_bootloader; 120 char *b = (char *)s->mb_buf + p; 121 122 memcpy(b, bootloader, strlen(bootloader) + 1); 123 s->offset_bootloader += strlen(b) + 1; 124 return s->mb_buf_phys + p; 125} 126 127static void mb_add_mod(MultibootState *s, 128 hwaddr start, hwaddr end, 129 hwaddr cmdline_phys) 130{ 131 char *p; 132 assert(s->mb_mods_count < s->mb_mods_avail); 133 134 p = (char *)s->mb_buf + s->offset_mbinfo + MB_MOD_SIZE * s->mb_mods_count; 135 136 stl_p(p + MB_MOD_START, start); 137 stl_p(p + MB_MOD_END, end); 138 stl_p(p + MB_MOD_CMDLINE, cmdline_phys); 139 140 mb_debug("mod%02d: "TARGET_FMT_plx" - "TARGET_FMT_plx, 141 s->mb_mods_count, start, end); 142 143 s->mb_mods_count++; 144} 145 146int load_multiboot(FWCfgState *fw_cfg, 147 FILE *f, 148 const char *kernel_filename, 149 const char *initrd_filename, 150 const char *kernel_cmdline, 151 int kernel_file_size, 152 uint8_t *header) 153{ 154 int i, is_multiboot = 0; 155 uint32_t flags = 0; 156 uint32_t mh_entry_addr; 157 uint32_t mh_load_addr; 158 uint32_t mb_kernel_size; 159 MultibootState mbs; 160 uint8_t bootinfo[MBI_SIZE]; 161 uint8_t *mb_bootinfo_data; 162 uint32_t cmdline_len; 163 GList *mods = NULL; 164 165 /* Ok, let's see if it is a multiboot image. 166 The header is 12x32bit long, so the latest entry may be 8192 - 48. */ 167 for (i = 0; i < (8192 - 48); i += 4) { 168 if (ldl_p(header+i) == 0x1BADB002) { 169 uint32_t checksum = ldl_p(header+i+8); 170 flags = ldl_p(header+i+4); 171 checksum += flags; 172 checksum += (uint32_t)0x1BADB002; 173 if (!checksum) { 174 is_multiboot = 1; 175 break; 176 } 177 } 178 } 179 180 if (!is_multiboot) 181 return 0; /* no multiboot */ 182 183 mb_debug("I believe we found a multiboot image!"); 184 memset(bootinfo, 0, sizeof(bootinfo)); 185 memset(&mbs, 0, sizeof(mbs)); 186 187 if (flags & 0x00000004) { /* MULTIBOOT_HEADER_HAS_VBE */ 188 error_report("multiboot knows VBE. we don't"); 189 } 190 if (!(flags & 0x00010000)) { /* MULTIBOOT_HEADER_HAS_ADDR */ 191 uint64_t elf_entry; 192 uint64_t elf_low, elf_high; 193 int kernel_size; 194 fclose(f); 195 196 if (((struct elf64_hdr*)header)->e_machine == EM_X86_64) { 197 error_report("Cannot load x86-64 image, give a 32bit one."); 198 exit(1); 199 } 200 201 kernel_size = load_elf(kernel_filename, NULL, NULL, NULL, &elf_entry, 202 &elf_low, &elf_high, NULL, 0, I386_ELF_MACHINE, 203 0, 0); 204 if (kernel_size < 0) { 205 error_report("Error while loading elf kernel"); 206 exit(1); 207 } 208 mh_load_addr = elf_low; 209 mb_kernel_size = elf_high - elf_low; 210 mh_entry_addr = elf_entry; 211 212 mbs.mb_buf = g_malloc(mb_kernel_size); 213 if (rom_copy(mbs.mb_buf, mh_load_addr, mb_kernel_size) != mb_kernel_size) { 214 error_report("Error while fetching elf kernel from rom"); 215 exit(1); 216 } 217 218 mb_debug("loading multiboot-elf kernel " 219 "(%#x bytes) with entry %#zx", 220 mb_kernel_size, (size_t)mh_entry_addr); 221 } else { 222 /* Valid if mh_flags sets MULTIBOOT_HEADER_HAS_ADDR. */ 223 uint32_t mh_header_addr = ldl_p(header+i+12); 224 uint32_t mh_load_end_addr = ldl_p(header+i+20); 225 uint32_t mh_bss_end_addr = ldl_p(header+i+24); 226 227 mh_load_addr = ldl_p(header+i+16); 228 if (mh_header_addr < mh_load_addr) { 229 error_report("invalid load_addr address"); 230 exit(1); 231 } 232 if (mh_header_addr - mh_load_addr > i) { 233 error_report("invalid header_addr address"); 234 exit(1); 235 } 236 237 uint32_t mb_kernel_text_offset = i - (mh_header_addr - mh_load_addr); 238 uint32_t mb_load_size = 0; 239 mh_entry_addr = ldl_p(header+i+28); 240 241 if (mh_load_end_addr) { 242 if (mh_load_end_addr < mh_load_addr) { 243 error_report("invalid load_end_addr address"); 244 exit(1); 245 } 246 mb_load_size = mh_load_end_addr - mh_load_addr; 247 } else { 248 if (kernel_file_size < mb_kernel_text_offset) { 249 error_report("invalid kernel_file_size"); 250 exit(1); 251 } 252 mb_load_size = kernel_file_size - mb_kernel_text_offset; 253 } 254 if (mb_load_size > UINT32_MAX - mh_load_addr) { 255 error_report("kernel does not fit in address space"); 256 exit(1); 257 } 258 if (mh_bss_end_addr) { 259 if (mh_bss_end_addr < (mh_load_addr + mb_load_size)) { 260 error_report("invalid bss_end_addr address"); 261 exit(1); 262 } 263 mb_kernel_size = mh_bss_end_addr - mh_load_addr; 264 } else { 265 mb_kernel_size = mb_load_size; 266 } 267 268 mb_debug("multiboot: header_addr = %#x", mh_header_addr); 269 mb_debug("multiboot: load_addr = %#x", mh_load_addr); 270 mb_debug("multiboot: load_end_addr = %#x", mh_load_end_addr); 271 mb_debug("multiboot: bss_end_addr = %#x", mh_bss_end_addr); 272 mb_debug("loading multiboot kernel (%#x bytes) at %#x", 273 mb_load_size, mh_load_addr); 274 275 mbs.mb_buf = g_malloc(mb_kernel_size); 276 fseek(f, mb_kernel_text_offset, SEEK_SET); 277 if (fread(mbs.mb_buf, 1, mb_load_size, f) != mb_load_size) { 278 error_report("fread() failed"); 279 exit(1); 280 } 281 memset(mbs.mb_buf + mb_load_size, 0, mb_kernel_size - mb_load_size); 282 fclose(f); 283 } 284 285 mbs.mb_buf_phys = mh_load_addr; 286 287 mbs.mb_buf_size = TARGET_PAGE_ALIGN(mb_kernel_size); 288 mbs.offset_mbinfo = mbs.mb_buf_size; 289 290 /* Calculate space for cmdlines, bootloader name, and mb_mods */ 291 cmdline_len = strlen(kernel_filename) + 1; 292 cmdline_len += strlen(kernel_cmdline) + 1; 293 if (initrd_filename) { 294 const char *r = initrd_filename; 295 cmdline_len += strlen(initrd_filename) + 1; 296 while (*r) { 297 char *value; 298 r = get_opt_value(r, &value); 299 mbs.mb_mods_avail++; 300 mods = g_list_append(mods, value); 301 if (*r) { 302 r++; 303 } 304 } 305 } 306 307 mbs.mb_buf_size += cmdline_len; 308 mbs.mb_buf_size += MB_MOD_SIZE * mbs.mb_mods_avail; 309 mbs.mb_buf_size += strlen(bootloader_name) + 1; 310 311 mbs.mb_buf_size = TARGET_PAGE_ALIGN(mbs.mb_buf_size); 312 313 /* enlarge mb_buf to hold cmdlines, bootloader, mb-info structs */ 314 mbs.mb_buf = g_realloc(mbs.mb_buf, mbs.mb_buf_size); 315 mbs.offset_cmdlines = mbs.offset_mbinfo + mbs.mb_mods_avail * MB_MOD_SIZE; 316 mbs.offset_bootloader = mbs.offset_cmdlines + cmdline_len; 317 318 if (mods) { 319 GList *tmpl = mods; 320 mbs.offset_mods = mbs.mb_buf_size; 321 322 while (tmpl) { 323 char *next_space; 324 int mb_mod_length; 325 uint32_t offs = mbs.mb_buf_size; 326 char *one_file = tmpl->data; 327 328 /* if a space comes after the module filename, treat everything 329 after that as parameters */ 330 hwaddr c = mb_add_cmdline(&mbs, one_file); 331 next_space = strchr(one_file, ' '); 332 if (next_space) { 333 *next_space = '\0'; 334 } 335 mb_debug("multiboot loading module: %s", one_file); 336 mb_mod_length = get_image_size(one_file); 337 if (mb_mod_length < 0) { 338 error_report("Failed to open file '%s'", one_file); 339 exit(1); 340 } 341 342 mbs.mb_buf_size = TARGET_PAGE_ALIGN(mb_mod_length + mbs.mb_buf_size); 343 mbs.mb_buf = g_realloc(mbs.mb_buf, mbs.mb_buf_size); 344 345 if (load_image_size(one_file, (unsigned char *)mbs.mb_buf + offs, 346 mbs.mb_buf_size - offs) < 0) { 347 error_report("Error loading file '%s'", one_file); 348 exit(1); 349 } 350 mb_add_mod(&mbs, mbs.mb_buf_phys + offs, 351 mbs.mb_buf_phys + offs + mb_mod_length, c); 352 353 mb_debug("mod_start: %p\nmod_end: %p\n cmdline: "TARGET_FMT_plx, 354 (char *)mbs.mb_buf + offs, 355 (char *)mbs.mb_buf + offs + mb_mod_length, c); 356 g_free(one_file); 357 tmpl = tmpl->next; 358 } 359 g_list_free(mods); 360 } 361 362 /* Commandline support */ 363 char kcmdline[strlen(kernel_filename) + strlen(kernel_cmdline) + 2]; 364 snprintf(kcmdline, sizeof(kcmdline), "%s %s", 365 kernel_filename, kernel_cmdline); 366 stl_p(bootinfo + MBI_CMDLINE, mb_add_cmdline(&mbs, kcmdline)); 367 368 stl_p(bootinfo + MBI_BOOTLOADER, mb_add_bootloader(&mbs, bootloader_name)); 369 370 stl_p(bootinfo + MBI_MODS_ADDR, mbs.mb_buf_phys + mbs.offset_mbinfo); 371 stl_p(bootinfo + MBI_MODS_COUNT, mbs.mb_mods_count); /* mods_count */ 372 373 /* the kernel is where we want it to be now */ 374 stl_p(bootinfo + MBI_FLAGS, MULTIBOOT_FLAGS_MEMORY 375 | MULTIBOOT_FLAGS_BOOT_DEVICE 376 | MULTIBOOT_FLAGS_CMDLINE 377 | MULTIBOOT_FLAGS_MODULES 378 | MULTIBOOT_FLAGS_MMAP 379 | MULTIBOOT_FLAGS_BOOTLOADER); 380 stl_p(bootinfo + MBI_BOOT_DEVICE, 0x8000ffff); /* XXX: use the -boot switch? */ 381 stl_p(bootinfo + MBI_MMAP_ADDR, ADDR_E820_MAP); 382 383 mb_debug("multiboot: entry_addr = %#x", mh_entry_addr); 384 mb_debug(" mb_buf_phys = "TARGET_FMT_plx, mbs.mb_buf_phys); 385 mb_debug(" mod_start = "TARGET_FMT_plx, 386 mbs.mb_buf_phys + mbs.offset_mods); 387 mb_debug(" mb_mods_count = %d", mbs.mb_mods_count); 388 389 /* save bootinfo off the stack */ 390 mb_bootinfo_data = g_memdup(bootinfo, sizeof(bootinfo)); 391 392 /* Pass variables to option rom */ 393 fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_ENTRY, mh_entry_addr); 394 fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_ADDR, mh_load_addr); 395 fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_SIZE, mbs.mb_buf_size); 396 fw_cfg_add_bytes(fw_cfg, FW_CFG_KERNEL_DATA, 397 mbs.mb_buf, mbs.mb_buf_size); 398 399 fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_ADDR, ADDR_MBI); 400 fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_SIZE, sizeof(bootinfo)); 401 fw_cfg_add_bytes(fw_cfg, FW_CFG_INITRD_DATA, mb_bootinfo_data, 402 sizeof(bootinfo)); 403 404 option_rom[nb_option_roms].name = "multiboot.bin"; 405 option_rom[nb_option_roms].bootindex = 0; 406 nb_option_roms++; 407 408 return 1; /* yes, we are multiboot */ 409}