1 /* 2 * crash.c - kernel crash support code. 3 * Copyright (C) 2002-2004 Eric Biederman <ebiederm@xmission.com> 4 * 5 * This source code is licensed under the GNU General Public License, 6 * Version 2. See the file COPYING for more details. 7 */ 8 9 #include <linux/crash_core.h> 10 #include <linux/utsname.h> 11 #include <linux/vmalloc.h> 12 13 #include <asm/page.h> 14 #include <asm/sections.h> 15 16 /* vmcoreinfo stuff */ 17 static unsigned char vmcoreinfo_data[VMCOREINFO_BYTES]; 18 u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4]; 19 size_t vmcoreinfo_size; 20 size_t vmcoreinfo_max_size = sizeof(vmcoreinfo_data); 21 22 /* 23 * parsing the "crashkernel" commandline 24 * 25 * this code is intended to be called from architecture specific code 26 */ 27 28 29 /* 30 * This function parses command lines in the format 31 * 32 * crashkernel=ramsize-range:size[,...][@offset] 33 * 34 * The function returns 0 on success and -EINVAL on failure. 35 */ 36 static int __init parse_crashkernel_mem(char *cmdline, 37 unsigned long long system_ram, 38 unsigned long long *crash_size, 39 unsigned long long *crash_base) 40 { 41 char *cur = cmdline, *tmp; 42 43 /* for each entry of the comma-separated list */ 44 do { 45 unsigned long long start, end = ULLONG_MAX, size; 46 47 /* get the start of the range */ 48 start = memparse(cur, &tmp); 49 if (cur == tmp) { 50 pr_warn("crashkernel: Memory value expected\n"); 51 return -EINVAL; 52 } 53 cur = tmp; 54 if (*cur != '-') { 55 pr_warn("crashkernel: '-' expected\n"); 56 return -EINVAL; 57 } 58 cur++; 59 60 /* if no ':' is here, than we read the end */ 61 if (*cur != ':') { 62 end = memparse(cur, &tmp); 63 if (cur == tmp) { 64 pr_warn("crashkernel: Memory value expected\n"); 65 return -EINVAL; 66 } 67 cur = tmp; 68 if (end <= start) { 69 pr_warn("crashkernel: end <= start\n"); 70 return -EINVAL; 71 } 72 } 73 74 if (*cur != ':') { 75 pr_warn("crashkernel: ':' expected\n"); 76 return -EINVAL; 77 } 78 cur++; 79 80 size = memparse(cur, &tmp); 81 if (cur == tmp) { 82 pr_warn("Memory value expected\n"); 83 return -EINVAL; 84 } 85 cur = tmp; 86 if (size >= system_ram) { 87 pr_warn("crashkernel: invalid size\n"); 88 return -EINVAL; 89 } 90 91 /* match ? */ 92 if (system_ram >= start && system_ram < end) { 93 *crash_size = size; 94 break; 95 } 96 } while (*cur++ == ','); 97 98 if (*crash_size > 0) { 99 while (*cur && *cur != ' ' && *cur != '@') 100 cur++; 101 if (*cur == '@') { 102 cur++; 103 *crash_base = memparse(cur, &tmp); 104 if (cur == tmp) { 105 pr_warn("Memory value expected after '@'\n"); 106 return -EINVAL; 107 } 108 } 109 } 110 111 return 0; 112 } 113 114 /* 115 * That function parses "simple" (old) crashkernel command lines like 116 * 117 * crashkernel=size[@offset] 118 * 119 * It returns 0 on success and -EINVAL on failure. 120 */ 121 static int __init parse_crashkernel_simple(char *cmdline, 122 unsigned long long *crash_size, 123 unsigned long long *crash_base) 124 { 125 char *cur = cmdline; 126 127 *crash_size = memparse(cmdline, &cur); 128 if (cmdline == cur) { 129 pr_warn("crashkernel: memory value expected\n"); 130 return -EINVAL; 131 } 132 133 if (*cur == '@') 134 *crash_base = memparse(cur+1, &cur); 135 else if (*cur != ' ' && *cur != '\0') { 136 pr_warn("crashkernel: unrecognized char: %c\n", *cur); 137 return -EINVAL; 138 } 139 140 return 0; 141 } 142 143 #define SUFFIX_HIGH 0 144 #define SUFFIX_LOW 1 145 #define SUFFIX_NULL 2 146 static __initdata char *suffix_tbl[] = { 147 [SUFFIX_HIGH] = ",high", 148 [SUFFIX_LOW] = ",low", 149 [SUFFIX_NULL] = NULL, 150 }; 151 152 /* 153 * That function parses "suffix" crashkernel command lines like 154 * 155 * crashkernel=size,[high|low] 156 * 157 * It returns 0 on success and -EINVAL on failure. 158 */ 159 static int __init parse_crashkernel_suffix(char *cmdline, 160 unsigned long long *crash_size, 161 const char *suffix) 162 { 163 char *cur = cmdline; 164 165 *crash_size = memparse(cmdline, &cur); 166 if (cmdline == cur) { 167 pr_warn("crashkernel: memory value expected\n"); 168 return -EINVAL; 169 } 170 171 /* check with suffix */ 172 if (strncmp(cur, suffix, strlen(suffix))) { 173 pr_warn("crashkernel: unrecognized char: %c\n", *cur); 174 return -EINVAL; 175 } 176 cur += strlen(suffix); 177 if (*cur != ' ' && *cur != '\0') { 178 pr_warn("crashkernel: unrecognized char: %c\n", *cur); 179 return -EINVAL; 180 } 181 182 return 0; 183 } 184 185 static __init char *get_last_crashkernel(char *cmdline, 186 const char *name, 187 const char *suffix) 188 { 189 char *p = cmdline, *ck_cmdline = NULL; 190 191 /* find crashkernel and use the last one if there are more */ 192 p = strstr(p, name); 193 while (p) { 194 char *end_p = strchr(p, ' '); 195 char *q; 196 197 if (!end_p) 198 end_p = p + strlen(p); 199 200 if (!suffix) { 201 int i; 202 203 /* skip the one with any known suffix */ 204 for (i = 0; suffix_tbl[i]; i++) { 205 q = end_p - strlen(suffix_tbl[i]); 206 if (!strncmp(q, suffix_tbl[i], 207 strlen(suffix_tbl[i]))) 208 goto next; 209 } 210 ck_cmdline = p; 211 } else { 212 q = end_p - strlen(suffix); 213 if (!strncmp(q, suffix, strlen(suffix))) 214 ck_cmdline = p; 215 } 216 next: 217 p = strstr(p+1, name); 218 } 219 220 if (!ck_cmdline) 221 return NULL; 222 223 return ck_cmdline; 224 } 225 226 static int __init __parse_crashkernel(char *cmdline, 227 unsigned long long system_ram, 228 unsigned long long *crash_size, 229 unsigned long long *crash_base, 230 const char *name, 231 const char *suffix) 232 { 233 char *first_colon, *first_space; 234 char *ck_cmdline; 235 236 BUG_ON(!crash_size || !crash_base); 237 *crash_size = 0; 238 *crash_base = 0; 239 240 ck_cmdline = get_last_crashkernel(cmdline, name, suffix); 241 242 if (!ck_cmdline) 243 return -EINVAL; 244 245 ck_cmdline += strlen(name); 246 247 if (suffix) 248 return parse_crashkernel_suffix(ck_cmdline, crash_size, 249 suffix); 250 /* 251 * if the commandline contains a ':', then that's the extended 252 * syntax -- if not, it must be the classic syntax 253 */ 254 first_colon = strchr(ck_cmdline, ':'); 255 first_space = strchr(ck_cmdline, ' '); 256 if (first_colon && (!first_space || first_colon < first_space)) 257 return parse_crashkernel_mem(ck_cmdline, system_ram, 258 crash_size, crash_base); 259 260 return parse_crashkernel_simple(ck_cmdline, crash_size, crash_base); 261 } 262 263 /* 264 * That function is the entry point for command line parsing and should be 265 * called from the arch-specific code. 266 */ 267 int __init parse_crashkernel(char *cmdline, 268 unsigned long long system_ram, 269 unsigned long long *crash_size, 270 unsigned long long *crash_base) 271 { 272 return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base, 273 "crashkernel=", NULL); 274 } 275 276 int __init parse_crashkernel_high(char *cmdline, 277 unsigned long long system_ram, 278 unsigned long long *crash_size, 279 unsigned long long *crash_base) 280 { 281 return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base, 282 "crashkernel=", suffix_tbl[SUFFIX_HIGH]); 283 } 284 285 int __init parse_crashkernel_low(char *cmdline, 286 unsigned long long system_ram, 287 unsigned long long *crash_size, 288 unsigned long long *crash_base) 289 { 290 return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base, 291 "crashkernel=", suffix_tbl[SUFFIX_LOW]); 292 } 293 294 Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type, 295 void *data, size_t data_len) 296 { 297 struct elf_note *note = (struct elf_note *)buf; 298 299 note->n_namesz = strlen(name) + 1; 300 note->n_descsz = data_len; 301 note->n_type = type; 302 buf += DIV_ROUND_UP(sizeof(*note), sizeof(Elf_Word)); 303 memcpy(buf, name, note->n_namesz); 304 buf += DIV_ROUND_UP(note->n_namesz, sizeof(Elf_Word)); 305 memcpy(buf, data, data_len); 306 buf += DIV_ROUND_UP(data_len, sizeof(Elf_Word)); 307 308 return buf; 309 } 310 311 void final_note(Elf_Word *buf) 312 { 313 memset(buf, 0, sizeof(struct elf_note)); 314 } 315 316 static void update_vmcoreinfo_note(void) 317 { 318 u32 *buf = vmcoreinfo_note; 319 320 if (!vmcoreinfo_size) 321 return; 322 buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data, 323 vmcoreinfo_size); 324 final_note(buf); 325 } 326 327 void crash_save_vmcoreinfo(void) 328 { 329 vmcoreinfo_append_str("CRASHTIME=%ld\n", get_seconds()); 330 update_vmcoreinfo_note(); 331 } 332 333 void vmcoreinfo_append_str(const char *fmt, ...) 334 { 335 va_list args; 336 char buf[0x50]; 337 size_t r; 338 339 va_start(args, fmt); 340 r = vscnprintf(buf, sizeof(buf), fmt, args); 341 va_end(args); 342 343 r = min(r, vmcoreinfo_max_size - vmcoreinfo_size); 344 345 memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r); 346 347 vmcoreinfo_size += r; 348 } 349 350 /* 351 * provide an empty default implementation here -- architecture 352 * code may override this 353 */ 354 void __weak arch_crash_save_vmcoreinfo(void) 355 {} 356 357 phys_addr_t __weak paddr_vmcoreinfo_note(void) 358 { 359 return __pa_symbol((unsigned long)(char *)&vmcoreinfo_note); 360 } 361 362 static int __init crash_save_vmcoreinfo_init(void) 363 { 364 VMCOREINFO_OSRELEASE(init_uts_ns.name.release); 365 VMCOREINFO_PAGESIZE(PAGE_SIZE); 366 367 VMCOREINFO_SYMBOL(init_uts_ns); 368 VMCOREINFO_SYMBOL(node_online_map); 369 #ifdef CONFIG_MMU 370 VMCOREINFO_SYMBOL(swapper_pg_dir); 371 #endif 372 VMCOREINFO_SYMBOL(_stext); 373 VMCOREINFO_SYMBOL(vmap_area_list); 374 375 #ifndef CONFIG_NEED_MULTIPLE_NODES 376 VMCOREINFO_SYMBOL(mem_map); 377 VMCOREINFO_SYMBOL(contig_page_data); 378 #endif 379 #ifdef CONFIG_SPARSEMEM 380 VMCOREINFO_SYMBOL(mem_section); 381 VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS); 382 VMCOREINFO_STRUCT_SIZE(mem_section); 383 VMCOREINFO_OFFSET(mem_section, section_mem_map); 384 #endif 385 VMCOREINFO_STRUCT_SIZE(page); 386 VMCOREINFO_STRUCT_SIZE(pglist_data); 387 VMCOREINFO_STRUCT_SIZE(zone); 388 VMCOREINFO_STRUCT_SIZE(free_area); 389 VMCOREINFO_STRUCT_SIZE(list_head); 390 VMCOREINFO_SIZE(nodemask_t); 391 VMCOREINFO_OFFSET(page, flags); 392 VMCOREINFO_OFFSET(page, _refcount); 393 VMCOREINFO_OFFSET(page, mapping); 394 VMCOREINFO_OFFSET(page, lru); 395 VMCOREINFO_OFFSET(page, _mapcount); 396 VMCOREINFO_OFFSET(page, private); 397 VMCOREINFO_OFFSET(page, compound_dtor); 398 VMCOREINFO_OFFSET(page, compound_order); 399 VMCOREINFO_OFFSET(page, compound_head); 400 VMCOREINFO_OFFSET(pglist_data, node_zones); 401 VMCOREINFO_OFFSET(pglist_data, nr_zones); 402 #ifdef CONFIG_FLAT_NODE_MEM_MAP 403 VMCOREINFO_OFFSET(pglist_data, node_mem_map); 404 #endif 405 VMCOREINFO_OFFSET(pglist_data, node_start_pfn); 406 VMCOREINFO_OFFSET(pglist_data, node_spanned_pages); 407 VMCOREINFO_OFFSET(pglist_data, node_id); 408 VMCOREINFO_OFFSET(zone, free_area); 409 VMCOREINFO_OFFSET(zone, vm_stat); 410 VMCOREINFO_OFFSET(zone, spanned_pages); 411 VMCOREINFO_OFFSET(free_area, free_list); 412 VMCOREINFO_OFFSET(list_head, next); 413 VMCOREINFO_OFFSET(list_head, prev); 414 VMCOREINFO_OFFSET(vmap_area, va_start); 415 VMCOREINFO_OFFSET(vmap_area, list); 416 VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER); 417 log_buf_vmcoreinfo_setup(); 418 VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES); 419 VMCOREINFO_NUMBER(NR_FREE_PAGES); 420 VMCOREINFO_NUMBER(PG_lru); 421 VMCOREINFO_NUMBER(PG_private); 422 VMCOREINFO_NUMBER(PG_swapcache); 423 VMCOREINFO_NUMBER(PG_slab); 424 #ifdef CONFIG_MEMORY_FAILURE 425 VMCOREINFO_NUMBER(PG_hwpoison); 426 #endif 427 VMCOREINFO_NUMBER(PG_head_mask); 428 VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE); 429 #ifdef CONFIG_HUGETLB_PAGE 430 VMCOREINFO_NUMBER(HUGETLB_PAGE_DTOR); 431 #endif 432 433 arch_crash_save_vmcoreinfo(); 434 update_vmcoreinfo_note(); 435 436 return 0; 437 } 438 439 subsys_initcall(crash_save_vmcoreinfo_init); 440