multiboot.c (14373B)
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 50 enum { 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 84 typedef 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; 104 105 const char *bootloader_name = "qemu"; 106 107 static 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 } 116 117 static 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 } 126 127 static 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 } 145 146 int load_multiboot(X86MachineState *x86ms, 147 FWCfgState *fw_cfg, 148 FILE *f, 149 const char *kernel_filename, 150 const char *initrd_filename, 151 const char *kernel_cmdline, 152 int kernel_file_size, 153 uint8_t *header) 154 { 155 bool multiboot_dma_enabled = X86_MACHINE_GET_CLASS(x86ms)->fwcfg_dma_enabled; 156 int i, is_multiboot = 0; 157 uint32_t flags = 0; 158 uint32_t mh_entry_addr; 159 uint32_t mh_load_addr; 160 uint32_t mb_kernel_size; 161 MultibootState mbs; 162 uint8_t bootinfo[MBI_SIZE]; 163 uint8_t *mb_bootinfo_data; 164 uint32_t cmdline_len; 165 GList *mods = NULL; 166 g_autofree char *kcmdline = NULL; 167 168 /* Ok, let's see if it is a multiboot image. 169 The header is 12x32bit long, so the latest entry may be 8192 - 48. */ 170 for (i = 0; i < (8192 - 48); i += 4) { 171 if (ldl_p(header+i) == 0x1BADB002) { 172 uint32_t checksum = ldl_p(header+i+8); 173 flags = ldl_p(header+i+4); 174 checksum += flags; 175 checksum += (uint32_t)0x1BADB002; 176 if (!checksum) { 177 is_multiboot = 1; 178 break; 179 } 180 } 181 } 182 183 if (!is_multiboot) 184 return 0; /* no multiboot */ 185 186 mb_debug("I believe we found a multiboot image!"); 187 memset(bootinfo, 0, sizeof(bootinfo)); 188 memset(&mbs, 0, sizeof(mbs)); 189 190 if (flags & 0x00000004) { /* MULTIBOOT_HEADER_HAS_VBE */ 191 error_report("multiboot knows VBE. we don't"); 192 } 193 if (!(flags & 0x00010000)) { /* MULTIBOOT_HEADER_HAS_ADDR */ 194 uint64_t elf_entry; 195 uint64_t elf_low, elf_high; 196 int kernel_size; 197 fclose(f); 198 199 if (((struct elf64_hdr*)header)->e_machine == EM_X86_64) { 200 error_report("Cannot load x86-64 image, give a 32bit one."); 201 exit(1); 202 } 203 204 kernel_size = load_elf(kernel_filename, NULL, NULL, NULL, &elf_entry, 205 &elf_low, &elf_high, NULL, 0, I386_ELF_MACHINE, 206 0, 0); 207 if (kernel_size < 0) { 208 error_report("Error while loading elf kernel"); 209 exit(1); 210 } 211 mh_load_addr = elf_low; 212 mb_kernel_size = elf_high - elf_low; 213 mh_entry_addr = elf_entry; 214 215 mbs.mb_buf = g_malloc(mb_kernel_size); 216 if (rom_copy(mbs.mb_buf, mh_load_addr, mb_kernel_size) != mb_kernel_size) { 217 error_report("Error while fetching elf kernel from rom"); 218 exit(1); 219 } 220 221 mb_debug("loading multiboot-elf kernel " 222 "(%#x bytes) with entry %#zx", 223 mb_kernel_size, (size_t)mh_entry_addr); 224 } else { 225 /* Valid if mh_flags sets MULTIBOOT_HEADER_HAS_ADDR. */ 226 uint32_t mh_header_addr = ldl_p(header+i+12); 227 uint32_t mh_load_end_addr = ldl_p(header+i+20); 228 uint32_t mh_bss_end_addr = ldl_p(header+i+24); 229 230 mh_load_addr = ldl_p(header+i+16); 231 if (mh_header_addr < mh_load_addr) { 232 error_report("invalid load_addr address"); 233 exit(1); 234 } 235 if (mh_header_addr - mh_load_addr > i) { 236 error_report("invalid header_addr address"); 237 exit(1); 238 } 239 240 uint32_t mb_kernel_text_offset = i - (mh_header_addr - mh_load_addr); 241 uint32_t mb_load_size = 0; 242 mh_entry_addr = ldl_p(header+i+28); 243 244 if (mh_load_end_addr) { 245 if (mh_load_end_addr < mh_load_addr) { 246 error_report("invalid load_end_addr address"); 247 exit(1); 248 } 249 mb_load_size = mh_load_end_addr - mh_load_addr; 250 } else { 251 if (kernel_file_size < mb_kernel_text_offset) { 252 error_report("invalid kernel_file_size"); 253 exit(1); 254 } 255 mb_load_size = kernel_file_size - mb_kernel_text_offset; 256 } 257 if (mb_load_size > UINT32_MAX - mh_load_addr) { 258 error_report("kernel does not fit in address space"); 259 exit(1); 260 } 261 if (mh_bss_end_addr) { 262 if (mh_bss_end_addr < (mh_load_addr + mb_load_size)) { 263 error_report("invalid bss_end_addr address"); 264 exit(1); 265 } 266 mb_kernel_size = mh_bss_end_addr - mh_load_addr; 267 } else { 268 mb_kernel_size = mb_load_size; 269 } 270 271 mb_debug("multiboot: header_addr = %#x", mh_header_addr); 272 mb_debug("multiboot: load_addr = %#x", mh_load_addr); 273 mb_debug("multiboot: load_end_addr = %#x", mh_load_end_addr); 274 mb_debug("multiboot: bss_end_addr = %#x", mh_bss_end_addr); 275 mb_debug("loading multiboot kernel (%#x bytes) at %#x", 276 mb_load_size, mh_load_addr); 277 278 mbs.mb_buf = g_malloc(mb_kernel_size); 279 fseek(f, mb_kernel_text_offset, SEEK_SET); 280 if (fread(mbs.mb_buf, 1, mb_load_size, f) != mb_load_size) { 281 error_report("fread() failed"); 282 exit(1); 283 } 284 memset(mbs.mb_buf + mb_load_size, 0, mb_kernel_size - mb_load_size); 285 fclose(f); 286 } 287 288 mbs.mb_buf_phys = mh_load_addr; 289 290 mbs.mb_buf_size = TARGET_PAGE_ALIGN(mb_kernel_size); 291 mbs.offset_mbinfo = mbs.mb_buf_size; 292 293 /* Calculate space for cmdlines, bootloader name, and mb_mods */ 294 cmdline_len = strlen(kernel_filename) + 1; 295 cmdline_len += strlen(kernel_cmdline) + 1; 296 if (initrd_filename) { 297 const char *r = initrd_filename; 298 cmdline_len += strlen(initrd_filename) + 1; 299 while (*r) { 300 char *value; 301 r = get_opt_value(r, &value); 302 mbs.mb_mods_avail++; 303 mods = g_list_append(mods, value); 304 if (*r) { 305 r++; 306 } 307 } 308 } 309 310 mbs.mb_buf_size += cmdline_len; 311 mbs.mb_buf_size += MB_MOD_SIZE * mbs.mb_mods_avail; 312 mbs.mb_buf_size += strlen(bootloader_name) + 1; 313 314 mbs.mb_buf_size = TARGET_PAGE_ALIGN(mbs.mb_buf_size); 315 316 /* enlarge mb_buf to hold cmdlines, bootloader, mb-info structs */ 317 mbs.mb_buf = g_realloc(mbs.mb_buf, mbs.mb_buf_size); 318 mbs.offset_cmdlines = mbs.offset_mbinfo + mbs.mb_mods_avail * MB_MOD_SIZE; 319 mbs.offset_bootloader = mbs.offset_cmdlines + cmdline_len; 320 321 if (mods) { 322 GList *tmpl = mods; 323 mbs.offset_mods = mbs.mb_buf_size; 324 325 while (tmpl) { 326 char *next_space; 327 int mb_mod_length; 328 uint32_t offs = mbs.mb_buf_size; 329 char *one_file = tmpl->data; 330 331 /* if a space comes after the module filename, treat everything 332 after that as parameters */ 333 hwaddr c = mb_add_cmdline(&mbs, one_file); 334 next_space = strchr(one_file, ' '); 335 if (next_space) { 336 *next_space = '\0'; 337 } 338 mb_debug("multiboot loading module: %s", one_file); 339 mb_mod_length = get_image_size(one_file); 340 if (mb_mod_length < 0) { 341 error_report("Failed to open file '%s'", one_file); 342 exit(1); 343 } 344 345 mbs.mb_buf_size = TARGET_PAGE_ALIGN(mb_mod_length + mbs.mb_buf_size); 346 mbs.mb_buf = g_realloc(mbs.mb_buf, mbs.mb_buf_size); 347 348 if (load_image_size(one_file, (unsigned char *)mbs.mb_buf + offs, 349 mbs.mb_buf_size - offs) < 0) { 350 error_report("Error loading file '%s'", one_file); 351 exit(1); 352 } 353 mb_add_mod(&mbs, mbs.mb_buf_phys + offs, 354 mbs.mb_buf_phys + offs + mb_mod_length, c); 355 356 mb_debug("mod_start: %p\nmod_end: %p\n cmdline: "TARGET_FMT_plx, 357 (char *)mbs.mb_buf + offs, 358 (char *)mbs.mb_buf + offs + mb_mod_length, c); 359 g_free(one_file); 360 tmpl = tmpl->next; 361 } 362 g_list_free(mods); 363 } 364 365 /* Commandline support */ 366 kcmdline = g_strdup_printf("%s %s", kernel_filename, kernel_cmdline); 367 stl_p(bootinfo + MBI_CMDLINE, mb_add_cmdline(&mbs, kcmdline)); 368 369 stl_p(bootinfo + MBI_BOOTLOADER, mb_add_bootloader(&mbs, bootloader_name)); 370 371 stl_p(bootinfo + MBI_MODS_ADDR, mbs.mb_buf_phys + mbs.offset_mbinfo); 372 stl_p(bootinfo + MBI_MODS_COUNT, mbs.mb_mods_count); /* mods_count */ 373 374 /* the kernel is where we want it to be now */ 375 stl_p(bootinfo + MBI_FLAGS, MULTIBOOT_FLAGS_MEMORY 376 | MULTIBOOT_FLAGS_BOOT_DEVICE 377 | MULTIBOOT_FLAGS_CMDLINE 378 | MULTIBOOT_FLAGS_MODULES 379 | MULTIBOOT_FLAGS_MMAP 380 | MULTIBOOT_FLAGS_BOOTLOADER); 381 stl_p(bootinfo + MBI_BOOT_DEVICE, 0x8000ffff); /* XXX: use the -boot switch? */ 382 stl_p(bootinfo + MBI_MMAP_ADDR, ADDR_E820_MAP); 383 384 mb_debug("multiboot: entry_addr = %#x", mh_entry_addr); 385 mb_debug(" mb_buf_phys = "TARGET_FMT_plx, mbs.mb_buf_phys); 386 mb_debug(" mod_start = "TARGET_FMT_plx, 387 mbs.mb_buf_phys + mbs.offset_mods); 388 mb_debug(" mb_mods_count = %d", mbs.mb_mods_count); 389 390 /* save bootinfo off the stack */ 391 mb_bootinfo_data = g_memdup(bootinfo, sizeof(bootinfo)); 392 393 /* Pass variables to option rom */ 394 fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_ENTRY, mh_entry_addr); 395 fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_ADDR, mh_load_addr); 396 fw_cfg_add_i32(fw_cfg, FW_CFG_KERNEL_SIZE, mbs.mb_buf_size); 397 fw_cfg_add_bytes(fw_cfg, FW_CFG_KERNEL_DATA, 398 mbs.mb_buf, mbs.mb_buf_size); 399 400 fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_ADDR, ADDR_MBI); 401 fw_cfg_add_i32(fw_cfg, FW_CFG_INITRD_SIZE, sizeof(bootinfo)); 402 fw_cfg_add_bytes(fw_cfg, FW_CFG_INITRD_DATA, mb_bootinfo_data, 403 sizeof(bootinfo)); 404 405 if (multiboot_dma_enabled) { 406 option_rom[nb_option_roms].name = "multiboot_dma.bin"; 407 } else { 408 option_rom[nb_option_roms].name = "multiboot.bin"; 409 } 410 option_rom[nb_option_roms].bootindex = 0; 411 nb_option_roms++; 412 413 return 1; /* yes, we are multiboot */ 414 }