1 /*- 2 * Mach Operating System 3 * Copyright (c) 1991,1990 Carnegie Mellon University 4 * All Rights Reserved. 5 * 6 * Permission to use, copy, modify and distribute this software and its 7 * documentation is hereby granted, provided that both the copyright 8 * notice and this permission notice appear in all copies of the 9 * software, derivative works or modified versions, and any portions 10 * thereof, and that both notices appear in supporting documentation. 11 * 12 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS 13 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR 14 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 15 * 16 * Carnegie Mellon requests users of this software to return to 17 * 18 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 19 * School of Computer Science 20 * Carnegie Mellon University 21 * Pittsburgh PA 15213-3890 22 * 23 * any improvements or extensions that they make and grant Carnegie the 24 * rights to redistribute these changes. 25 */ 26 /* 27 * Author: David B. Golub, Carnegie Mellon University 28 * Date: 7/90 29 */ 30 31 #include <sys/cdefs.h> 32 __FBSDID("$FreeBSD$"); 33 34 #include "opt_kstack_pages.h" 35 36 #include <sys/param.h> 37 #include <sys/pcpu.h> 38 #include <sys/smp.h> 39 #include <sys/systm.h> 40 41 #include <net/vnet.h> 42 43 #include <ddb/ddb.h> 44 #include <ddb/db_sym.h> 45 #include <ddb/db_variables.h> 46 47 #include <opt_ddb.h> 48 49 /* 50 * Multiple symbol tables 51 */ 52 #ifndef MAXNOSYMTABS 53 #define MAXNOSYMTABS 3 /* mach, ux, emulator */ 54 #endif 55 56 static db_symtab_t db_symtabs[MAXNOSYMTABS] = {{0,},}; 57 static int db_nsymtab = 0; 58 59 static db_symtab_t *db_last_symtab; /* where last symbol was found */ 60 61 static c_db_sym_t db_lookup( const char *symstr); 62 static char *db_qualify(c_db_sym_t sym, char *symtabname); 63 static bool db_symbol_is_ambiguous(c_db_sym_t sym); 64 static bool db_line_at_pc(c_db_sym_t, char **, int *, db_expr_t); 65 66 static int db_cpu = -1; 67 68 #ifdef VIMAGE 69 static void *db_vnet = NULL; 70 #endif 71 72 /* 73 * Validate the CPU number used to interpret per-CPU variables so we can 74 * avoid later confusion if an invalid CPU is requested. 75 */ 76 int 77 db_var_db_cpu(struct db_variable *vp, db_expr_t *valuep, int op) 78 { 79 80 switch (op) { 81 case DB_VAR_GET: 82 *valuep = db_cpu; 83 return (1); 84 85 case DB_VAR_SET: 86 if (*(int *)valuep < -1 && *(int *)valuep > mp_maxid) { 87 db_printf("Invalid value: %d", *(int*)valuep); 88 return (0); 89 } 90 db_cpu = *(int *)valuep; 91 return (1); 92 93 default: 94 db_printf("db_var_db_cpu: unknown operation\n"); 95 return (0); 96 } 97 } 98 99 /* 100 * Read-only variable reporting the current CPU, which is what we use when 101 * db_cpu is set to -1. 102 */ 103 int 104 db_var_curcpu(struct db_variable *vp, db_expr_t *valuep, int op) 105 { 106 107 switch (op) { 108 case DB_VAR_GET: 109 *valuep = curcpu; 110 return (1); 111 112 case DB_VAR_SET: 113 db_printf("Read-only variable.\n"); 114 return (0); 115 116 default: 117 db_printf("db_var_curcpu: unknown operation\n"); 118 return (0); 119 } 120 } 121 122 #ifdef VIMAGE 123 /* 124 * Validate the virtual network pointer used to interpret per-vnet global 125 * variable expansion. Right now we don't do much here, really we should 126 * walk the global vnet list to check it's an OK pointer. 127 */ 128 int 129 db_var_db_vnet(struct db_variable *vp, db_expr_t *valuep, int op) 130 { 131 132 switch (op) { 133 case DB_VAR_GET: 134 *valuep = (db_expr_t)db_vnet; 135 return (1); 136 137 case DB_VAR_SET: 138 db_vnet = *(void **)valuep; 139 return (1); 140 141 default: 142 db_printf("db_var_db_vnet: unknown operation\n"); 143 return (0); 144 } 145 } 146 147 /* 148 * Read-only variable reporting the current vnet, which is what we use when 149 * db_vnet is set to NULL. 150 */ 151 int 152 db_var_curvnet(struct db_variable *vp, db_expr_t *valuep, int op) 153 { 154 155 switch (op) { 156 case DB_VAR_GET: 157 *valuep = (db_expr_t)curvnet; 158 return (1); 159 160 case DB_VAR_SET: 161 db_printf("Read-only variable.\n"); 162 return (0); 163 164 default: 165 db_printf("db_var_curvnet: unknown operation\n"); 166 return (0); 167 } 168 } 169 #endif 170 171 /* 172 * Add symbol table, with given name, to list of symbol tables. 173 */ 174 void 175 db_add_symbol_table(char *start, char *end, char *name, char *ref) 176 { 177 if (db_nsymtab >= MAXNOSYMTABS) { 178 printf ("No slots left for %s symbol table", name); 179 panic ("db_sym.c: db_add_symbol_table"); 180 } 181 182 db_symtabs[db_nsymtab].start = start; 183 db_symtabs[db_nsymtab].end = end; 184 db_symtabs[db_nsymtab].name = name; 185 db_symtabs[db_nsymtab].private = ref; 186 db_nsymtab++; 187 } 188 189 /* 190 * db_qualify("vm_map", "ux") returns "unix:vm_map". 191 * 192 * Note: return value points to static data whose content is 193 * overwritten by each call... but in practice this seems okay. 194 */ 195 static char * 196 db_qualify(c_db_sym_t sym, char *symtabname) 197 { 198 const char *symname; 199 static char tmp[256]; 200 201 db_symbol_values(sym, &symname, 0); 202 snprintf(tmp, sizeof(tmp), "%s:%s", symtabname, symname); 203 return tmp; 204 } 205 206 207 bool 208 db_eqname(const char *src, const char *dst, int c) 209 { 210 if (!strcmp(src, dst)) 211 return (true); 212 if (src[0] == c) 213 return (!strcmp(src+1,dst)); 214 return (false); 215 } 216 217 bool 218 db_value_of_name(const char *name, db_expr_t *valuep) 219 { 220 c_db_sym_t sym; 221 222 sym = db_lookup(name); 223 if (sym == C_DB_SYM_NULL) 224 return (false); 225 db_symbol_values(sym, &name, valuep); 226 return (true); 227 } 228 229 bool 230 db_value_of_name_pcpu(const char *name, db_expr_t *valuep) 231 { 232 static char tmp[256]; 233 db_expr_t value; 234 c_db_sym_t sym; 235 int cpu; 236 237 if (db_cpu != -1) 238 cpu = db_cpu; 239 else 240 cpu = curcpu; 241 snprintf(tmp, sizeof(tmp), "pcpu_entry_%s", name); 242 sym = db_lookup(tmp); 243 if (sym == C_DB_SYM_NULL) 244 return (false); 245 db_symbol_values(sym, &name, &value); 246 if (value < DPCPU_START || value >= DPCPU_STOP) 247 return (false); 248 *valuep = (db_expr_t)((uintptr_t)value + dpcpu_off[cpu]); 249 return (true); 250 } 251 252 bool 253 db_value_of_name_vnet(const char *name, db_expr_t *valuep) 254 { 255 #ifdef VIMAGE 256 static char tmp[256]; 257 db_expr_t value; 258 c_db_sym_t sym; 259 struct vnet *vnet; 260 261 if (db_vnet != NULL) 262 vnet = db_vnet; 263 else 264 vnet = curvnet; 265 snprintf(tmp, sizeof(tmp), "vnet_entry_%s", name); 266 sym = db_lookup(tmp); 267 if (sym == C_DB_SYM_NULL) 268 return (false); 269 db_symbol_values(sym, &name, &value); 270 if (value < VNET_START || value >= VNET_STOP) 271 return (false); 272 *valuep = (db_expr_t)((uintptr_t)value + vnet->vnet_data_base); 273 return (true); 274 #else 275 return (false); 276 #endif 277 } 278 279 /* 280 * Lookup a symbol. 281 * If the symbol has a qualifier (e.g., ux:vm_map), 282 * then only the specified symbol table will be searched; 283 * otherwise, all symbol tables will be searched. 284 */ 285 static c_db_sym_t 286 db_lookup(const char *symstr) 287 { 288 c_db_sym_t sp; 289 register int i; 290 int symtab_start = 0; 291 int symtab_end = db_nsymtab; 292 register const char *cp; 293 294 /* 295 * Look for, remove, and remember any symbol table specifier. 296 */ 297 for (cp = symstr; *cp; cp++) { 298 if (*cp == ':') { 299 for (i = 0; i < db_nsymtab; i++) { 300 int n = strlen(db_symtabs[i].name); 301 302 if ( 303 n == (cp - symstr) && 304 strncmp(symstr, db_symtabs[i].name, n) == 0 305 ) { 306 symtab_start = i; 307 symtab_end = i + 1; 308 break; 309 } 310 } 311 if (i == db_nsymtab) { 312 db_error("invalid symbol table name"); 313 } 314 symstr = cp+1; 315 } 316 } 317 318 /* 319 * Look in the specified set of symbol tables. 320 * Return on first match. 321 */ 322 for (i = symtab_start; i < symtab_end; i++) { 323 sp = X_db_lookup(&db_symtabs[i], symstr); 324 if (sp) { 325 db_last_symtab = &db_symtabs[i]; 326 return sp; 327 } 328 } 329 return 0; 330 } 331 332 /* 333 * If true, check across symbol tables for multiple occurrences 334 * of a name. Might slow things down quite a bit. 335 */ 336 static volatile bool db_qualify_ambiguous_names = false; 337 338 /* 339 * Does this symbol name appear in more than one symbol table? 340 * Used by db_symbol_values to decide whether to qualify a symbol. 341 */ 342 static bool 343 db_symbol_is_ambiguous(c_db_sym_t sym) 344 { 345 const char *sym_name; 346 register int i; 347 register bool found_once = false; 348 349 if (!db_qualify_ambiguous_names) 350 return (false); 351 352 db_symbol_values(sym, &sym_name, 0); 353 for (i = 0; i < db_nsymtab; i++) { 354 if (X_db_lookup(&db_symtabs[i], sym_name)) { 355 if (found_once) 356 return (true); 357 found_once = true; 358 } 359 } 360 return (false); 361 } 362 363 /* 364 * Find the closest symbol to val, and return its name 365 * and the difference between val and the symbol found. 366 */ 367 c_db_sym_t 368 db_search_symbol(db_addr_t val, db_strategy_t strategy, db_expr_t *offp) 369 { 370 register 371 unsigned int diff; 372 size_t newdiff; 373 register int i; 374 c_db_sym_t ret = C_DB_SYM_NULL, sym; 375 376 newdiff = diff = val; 377 for (i = 0; i < db_nsymtab; i++) { 378 sym = X_db_search_symbol(&db_symtabs[i], val, strategy, &newdiff); 379 if ((uintmax_t)newdiff < (uintmax_t)diff) { 380 db_last_symtab = &db_symtabs[i]; 381 diff = newdiff; 382 ret = sym; 383 } 384 } 385 *offp = diff; 386 return ret; 387 } 388 389 /* 390 * Return name and value of a symbol 391 */ 392 void 393 db_symbol_values(c_db_sym_t sym, const char **namep, db_expr_t *valuep) 394 { 395 db_expr_t value; 396 397 if (sym == DB_SYM_NULL) { 398 *namep = NULL; 399 return; 400 } 401 402 X_db_symbol_values(db_last_symtab, sym, namep, &value); 403 404 if (db_symbol_is_ambiguous(sym)) 405 *namep = db_qualify(sym, db_last_symtab->name); 406 if (valuep) 407 *valuep = value; 408 } 409 410 411 /* 412 * Print a the closest symbol to value 413 * 414 * After matching the symbol according to the given strategy 415 * we print it in the name+offset format, provided the symbol's 416 * value is close enough (eg smaller than db_maxoff). 417 * We also attempt to print [filename:linenum] when applicable 418 * (eg for procedure names). 419 * 420 * If we could not find a reasonable name+offset representation, 421 * then we just print the value in hex. Small values might get 422 * bogus symbol associations, e.g. 3 might get some absolute 423 * value like _INCLUDE_VERSION or something, therefore we do 424 * not accept symbols whose value is "small" (and use plain hex). 425 */ 426 427 db_expr_t db_maxoff = 0x10000; 428 429 void 430 db_printsym(db_expr_t off, db_strategy_t strategy) 431 { 432 db_expr_t d; 433 char *filename; 434 const char *name; 435 int linenum; 436 c_db_sym_t cursym; 437 438 if (off < 0 && off >= -db_maxoff) { 439 db_printf("%+#lr", (long)off); 440 return; 441 } 442 cursym = db_search_symbol(off, strategy, &d); 443 db_symbol_values(cursym, &name, NULL); 444 if (name == NULL || d >= (db_addr_t)db_maxoff) { 445 db_printf("%#lr", (unsigned long)off); 446 return; 447 } 448 #ifdef DDB_NUMSYM 449 db_printf("%#lr = %s", (unsigned long)off, name); 450 #else 451 db_printf("%s", name); 452 #endif 453 if (d) 454 db_printf("+%+#lr", (long)d); 455 if (strategy == DB_STGY_PROC) { 456 if (db_line_at_pc(cursym, &filename, &linenum, off)) 457 db_printf(" [%s:%d]", filename, linenum); 458 } 459 } 460 461 static bool 462 db_line_at_pc(c_db_sym_t sym, char **filename, int *linenum, db_expr_t pc) 463 { 464 return (X_db_line_at_pc(db_last_symtab, sym, filename, linenum, pc)); 465 } 466 467 bool 468 db_sym_numargs(c_db_sym_t sym, int *nargp, char **argnames) 469 { 470 return (X_db_sym_numargs(db_last_symtab, sym, nargp, argnames)); 471 } 472