1 /* 2 * lib/dynamic_debug.c 3 * 4 * make pr_debug()/dev_dbg() calls runtime configurable based upon their 5 * source module. 6 * 7 * Copyright (C) 2008 Jason Baron <jbaron@redhat.com> 8 * By Greg Banks <gnb@melbourne.sgi.com> 9 * Copyright (c) 2008 Silicon Graphics Inc. All Rights Reserved. 10 * Copyright (C) 2011 Bart Van Assche. All Rights Reserved. 11 * Copyright (C) 2013 Du, Changbin <changbin.du@gmail.com> 12 */ 13 14 #define pr_fmt(fmt) "dyndbg: " fmt 15 16 #include <linux/kernel.h> 17 #include <linux/module.h> 18 #include <linux/moduleparam.h> 19 #include <linux/kallsyms.h> 20 #include <linux/types.h> 21 #include <linux/mutex.h> 22 #include <linux/proc_fs.h> 23 #include <linux/seq_file.h> 24 #include <linux/list.h> 25 #include <linux/sysctl.h> 26 #include <linux/ctype.h> 27 #include <linux/string.h> 28 #include <linux/parser.h> 29 #include <linux/string_helpers.h> 30 #include <linux/uaccess.h> 31 #include <linux/dynamic_debug.h> 32 #include <linux/debugfs.h> 33 #include <linux/slab.h> 34 #include <linux/jump_label.h> 35 #include <linux/hardirq.h> 36 #include <linux/sched.h> 37 #include <linux/device.h> 38 #include <linux/netdevice.h> 39 40 #include <rdma/ib_verbs.h> 41 42 extern struct _ddebug __start___dyndbg[]; 43 extern struct _ddebug __stop___dyndbg[]; 44 extern struct ddebug_class_map __start___dyndbg_classes[]; 45 extern struct ddebug_class_map __stop___dyndbg_classes[]; 46 47 struct ddebug_table { 48 struct list_head link, maps; 49 const char *mod_name; 50 unsigned int num_ddebugs; 51 struct _ddebug *ddebugs; 52 }; 53 54 struct ddebug_query { 55 const char *filename; 56 const char *module; 57 const char *function; 58 const char *format; 59 const char *class_string; 60 unsigned int first_lineno, last_lineno; 61 }; 62 63 struct ddebug_iter { 64 struct ddebug_table *table; 65 int idx; 66 }; 67 68 struct flag_settings { 69 unsigned int flags; 70 unsigned int mask; 71 }; 72 73 static DEFINE_MUTEX(ddebug_lock); 74 static LIST_HEAD(ddebug_tables); 75 static int verbose; 76 module_param(verbose, int, 0644); 77 MODULE_PARM_DESC(verbose, " dynamic_debug/control processing " 78 "( 0 = off (default), 1 = module add/rm, 2 = >control summary, 3 = parsing, 4 = per-site changes)"); 79 80 /* Return the path relative to source root */ 81 static inline const char *trim_prefix(const char *path) 82 { 83 int skip = strlen(__FILE__) - strlen("lib/dynamic_debug.c"); 84 85 if (strncmp(path, __FILE__, skip)) 86 skip = 0; /* prefix mismatch, don't skip */ 87 88 return path + skip; 89 } 90 91 static const struct { unsigned flag:8; char opt_char; } opt_array[] = { 92 { _DPRINTK_FLAGS_PRINT, 'p' }, 93 { _DPRINTK_FLAGS_INCL_MODNAME, 'm' }, 94 { _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' }, 95 { _DPRINTK_FLAGS_INCL_SOURCENAME, 's' }, 96 { _DPRINTK_FLAGS_INCL_LINENO, 'l' }, 97 { _DPRINTK_FLAGS_INCL_TID, 't' }, 98 { _DPRINTK_FLAGS_NONE, '_' }, 99 }; 100 101 struct flagsbuf { char buf[ARRAY_SIZE(opt_array)+1]; }; 102 103 /* format a string into buf[] which describes the _ddebug's flags */ 104 static char *ddebug_describe_flags(unsigned int flags, struct flagsbuf *fb) 105 { 106 char *p = fb->buf; 107 int i; 108 109 for (i = 0; i < ARRAY_SIZE(opt_array); ++i) 110 if (flags & opt_array[i].flag) 111 *p++ = opt_array[i].opt_char; 112 if (p == fb->buf) 113 *p++ = '_'; 114 *p = '\0'; 115 116 return fb->buf; 117 } 118 119 #define vnpr_info(lvl, fmt, ...) \ 120 do { \ 121 if (verbose >= lvl) \ 122 pr_info(fmt, ##__VA_ARGS__); \ 123 } while (0) 124 125 #define vpr_info(fmt, ...) vnpr_info(1, fmt, ##__VA_ARGS__) 126 #define v2pr_info(fmt, ...) vnpr_info(2, fmt, ##__VA_ARGS__) 127 #define v3pr_info(fmt, ...) vnpr_info(3, fmt, ##__VA_ARGS__) 128 #define v4pr_info(fmt, ...) vnpr_info(4, fmt, ##__VA_ARGS__) 129 130 static void vpr_info_dq(const struct ddebug_query *query, const char *msg) 131 { 132 /* trim any trailing newlines */ 133 int fmtlen = 0; 134 135 if (query->format) { 136 fmtlen = strlen(query->format); 137 while (fmtlen && query->format[fmtlen - 1] == '\n') 138 fmtlen--; 139 } 140 141 v3pr_info("%s: func=\"%s\" file=\"%s\" module=\"%s\" format=\"%.*s\" lineno=%u-%u class=%s\n", 142 msg, 143 query->function ?: "", 144 query->filename ?: "", 145 query->module ?: "", 146 fmtlen, query->format ?: "", 147 query->first_lineno, query->last_lineno, query->class_string); 148 } 149 150 static struct ddebug_class_map *ddebug_find_valid_class(struct ddebug_table const *dt, 151 const char *class_string, int *class_id) 152 { 153 struct ddebug_class_map *map; 154 int idx; 155 156 list_for_each_entry(map, &dt->maps, link) { 157 idx = match_string(map->class_names, map->length, class_string); 158 if (idx >= 0) { 159 *class_id = idx + map->base; 160 return map; 161 } 162 } 163 *class_id = -ENOENT; 164 return NULL; 165 } 166 167 #define __outvar /* filled by callee */ 168 /* 169 * Search the tables for _ddebug's which match the given `query' and 170 * apply the `flags' and `mask' to them. Returns number of matching 171 * callsites, normally the same as number of changes. If verbose, 172 * logs the changes. Takes ddebug_lock. 173 */ 174 static int ddebug_change(const struct ddebug_query *query, 175 struct flag_settings *modifiers) 176 { 177 int i; 178 struct ddebug_table *dt; 179 unsigned int newflags; 180 unsigned int nfound = 0; 181 struct flagsbuf fbuf, nbuf; 182 struct ddebug_class_map *map = NULL; 183 int __outvar valid_class; 184 185 /* search for matching ddebugs */ 186 mutex_lock(&ddebug_lock); 187 list_for_each_entry(dt, &ddebug_tables, link) { 188 189 /* match against the module name */ 190 if (query->module && 191 !match_wildcard(query->module, dt->mod_name)) 192 continue; 193 194 if (query->class_string) { 195 map = ddebug_find_valid_class(dt, query->class_string, &valid_class); 196 if (!map) 197 continue; 198 } else { 199 /* constrain query, do not touch class'd callsites */ 200 valid_class = _DPRINTK_CLASS_DFLT; 201 } 202 203 for (i = 0; i < dt->num_ddebugs; i++) { 204 struct _ddebug *dp = &dt->ddebugs[i]; 205 206 /* match site against query-class */ 207 if (dp->class_id != valid_class) 208 continue; 209 210 /* match against the source filename */ 211 if (query->filename && 212 !match_wildcard(query->filename, dp->filename) && 213 !match_wildcard(query->filename, 214 kbasename(dp->filename)) && 215 !match_wildcard(query->filename, 216 trim_prefix(dp->filename))) 217 continue; 218 219 /* match against the function */ 220 if (query->function && 221 !match_wildcard(query->function, dp->function)) 222 continue; 223 224 /* match against the format */ 225 if (query->format) { 226 if (*query->format == '^') { 227 char *p; 228 /* anchored search. match must be at beginning */ 229 p = strstr(dp->format, query->format+1); 230 if (p != dp->format) 231 continue; 232 } else if (!strstr(dp->format, query->format)) 233 continue; 234 } 235 236 /* match against the line number range */ 237 if (query->first_lineno && 238 dp->lineno < query->first_lineno) 239 continue; 240 if (query->last_lineno && 241 dp->lineno > query->last_lineno) 242 continue; 243 244 nfound++; 245 246 newflags = (dp->flags & modifiers->mask) | modifiers->flags; 247 if (newflags == dp->flags) 248 continue; 249 #ifdef CONFIG_JUMP_LABEL 250 if (dp->flags & _DPRINTK_FLAGS_PRINT) { 251 if (!(newflags & _DPRINTK_FLAGS_PRINT)) 252 static_branch_disable(&dp->key.dd_key_true); 253 } else if (newflags & _DPRINTK_FLAGS_PRINT) { 254 static_branch_enable(&dp->key.dd_key_true); 255 } 256 #endif 257 v4pr_info("changed %s:%d [%s]%s %s => %s\n", 258 trim_prefix(dp->filename), dp->lineno, 259 dt->mod_name, dp->function, 260 ddebug_describe_flags(dp->flags, &fbuf), 261 ddebug_describe_flags(newflags, &nbuf)); 262 dp->flags = newflags; 263 } 264 } 265 mutex_unlock(&ddebug_lock); 266 267 if (!nfound && verbose) 268 pr_info("no matches for query\n"); 269 270 return nfound; 271 } 272 273 /* 274 * Split the buffer `buf' into space-separated words. 275 * Handles simple " and ' quoting, i.e. without nested, 276 * embedded or escaped \". Return the number of words 277 * or <0 on error. 278 */ 279 static int ddebug_tokenize(char *buf, char *words[], int maxwords) 280 { 281 int nwords = 0; 282 283 while (*buf) { 284 char *end; 285 286 /* Skip leading whitespace */ 287 buf = skip_spaces(buf); 288 if (!*buf) 289 break; /* oh, it was trailing whitespace */ 290 if (*buf == '#') 291 break; /* token starts comment, skip rest of line */ 292 293 /* find `end' of word, whitespace separated or quoted */ 294 if (*buf == '"' || *buf == '\'') { 295 int quote = *buf++; 296 for (end = buf; *end && *end != quote; end++) 297 ; 298 if (!*end) { 299 pr_err("unclosed quote: %s\n", buf); 300 return -EINVAL; /* unclosed quote */ 301 } 302 } else { 303 for (end = buf; *end && !isspace(*end); end++) 304 ; 305 BUG_ON(end == buf); 306 } 307 308 /* `buf' is start of word, `end' is one past its end */ 309 if (nwords == maxwords) { 310 pr_err("too many words, legal max <=%d\n", maxwords); 311 return -EINVAL; /* ran out of words[] before bytes */ 312 } 313 if (*end) 314 *end++ = '\0'; /* terminate the word */ 315 words[nwords++] = buf; 316 buf = end; 317 } 318 319 if (verbose >= 3) { 320 int i; 321 pr_info("split into words:"); 322 for (i = 0; i < nwords; i++) 323 pr_cont(" \"%s\"", words[i]); 324 pr_cont("\n"); 325 } 326 327 return nwords; 328 } 329 330 /* 331 * Parse a single line number. Note that the empty string "" 332 * is treated as a special case and converted to zero, which 333 * is later treated as a "don't care" value. 334 */ 335 static inline int parse_lineno(const char *str, unsigned int *val) 336 { 337 BUG_ON(str == NULL); 338 if (*str == '\0') { 339 *val = 0; 340 return 0; 341 } 342 if (kstrtouint(str, 10, val) < 0) { 343 pr_err("bad line-number: %s\n", str); 344 return -EINVAL; 345 } 346 return 0; 347 } 348 349 static int parse_linerange(struct ddebug_query *query, const char *first) 350 { 351 char *last = strchr(first, '-'); 352 353 if (query->first_lineno || query->last_lineno) { 354 pr_err("match-spec: line used 2x\n"); 355 return -EINVAL; 356 } 357 if (last) 358 *last++ = '\0'; 359 if (parse_lineno(first, &query->first_lineno) < 0) 360 return -EINVAL; 361 if (last) { 362 /* range <first>-<last> */ 363 if (parse_lineno(last, &query->last_lineno) < 0) 364 return -EINVAL; 365 366 /* special case for last lineno not specified */ 367 if (query->last_lineno == 0) 368 query->last_lineno = UINT_MAX; 369 370 if (query->last_lineno < query->first_lineno) { 371 pr_err("last-line:%d < 1st-line:%d\n", 372 query->last_lineno, 373 query->first_lineno); 374 return -EINVAL; 375 } 376 } else { 377 query->last_lineno = query->first_lineno; 378 } 379 v3pr_info("parsed line %d-%d\n", query->first_lineno, 380 query->last_lineno); 381 return 0; 382 } 383 384 static int check_set(const char **dest, char *src, char *name) 385 { 386 int rc = 0; 387 388 if (*dest) { 389 rc = -EINVAL; 390 pr_err("match-spec:%s val:%s overridden by %s\n", 391 name, *dest, src); 392 } 393 *dest = src; 394 return rc; 395 } 396 397 /* 398 * Parse words[] as a ddebug query specification, which is a series 399 * of (keyword, value) pairs chosen from these possibilities: 400 * 401 * func <function-name> 402 * file <full-pathname> 403 * file <base-filename> 404 * module <module-name> 405 * format <escaped-string-to-find-in-format> 406 * line <lineno> 407 * line <first-lineno>-<last-lineno> // where either may be empty 408 * 409 * Only 1 of each type is allowed. 410 * Returns 0 on success, <0 on error. 411 */ 412 static int ddebug_parse_query(char *words[], int nwords, 413 struct ddebug_query *query, const char *modname) 414 { 415 unsigned int i; 416 int rc = 0; 417 char *fline; 418 419 /* check we have an even number of words */ 420 if (nwords % 2 != 0) { 421 pr_err("expecting pairs of match-spec <value>\n"); 422 return -EINVAL; 423 } 424 425 for (i = 0; i < nwords; i += 2) { 426 char *keyword = words[i]; 427 char *arg = words[i+1]; 428 429 if (!strcmp(keyword, "func")) { 430 rc = check_set(&query->function, arg, "func"); 431 } else if (!strcmp(keyword, "file")) { 432 if (check_set(&query->filename, arg, "file")) 433 return -EINVAL; 434 435 /* tail :$info is function or line-range */ 436 fline = strchr(query->filename, ':'); 437 if (!fline) 438 continue; 439 *fline++ = '\0'; 440 if (isalpha(*fline) || *fline == '*' || *fline == '?') { 441 /* take as function name */ 442 if (check_set(&query->function, fline, "func")) 443 return -EINVAL; 444 } else { 445 if (parse_linerange(query, fline)) 446 return -EINVAL; 447 } 448 } else if (!strcmp(keyword, "module")) { 449 rc = check_set(&query->module, arg, "module"); 450 } else if (!strcmp(keyword, "format")) { 451 string_unescape_inplace(arg, UNESCAPE_SPACE | 452 UNESCAPE_OCTAL | 453 UNESCAPE_SPECIAL); 454 rc = check_set(&query->format, arg, "format"); 455 } else if (!strcmp(keyword, "line")) { 456 if (parse_linerange(query, arg)) 457 return -EINVAL; 458 } else if (!strcmp(keyword, "class")) { 459 rc = check_set(&query->class_string, arg, "class"); 460 } else { 461 pr_err("unknown keyword \"%s\"\n", keyword); 462 return -EINVAL; 463 } 464 if (rc) 465 return rc; 466 } 467 if (!query->module && modname) 468 /* 469 * support $modname.dyndbg=<multiple queries>, when 470 * not given in the query itself 471 */ 472 query->module = modname; 473 474 vpr_info_dq(query, "parsed"); 475 return 0; 476 } 477 478 /* 479 * Parse `str' as a flags specification, format [-+=][p]+. 480 * Sets up *maskp and *flagsp to be used when changing the 481 * flags fields of matched _ddebug's. Returns 0 on success 482 * or <0 on error. 483 */ 484 static int ddebug_parse_flags(const char *str, struct flag_settings *modifiers) 485 { 486 int op, i; 487 488 switch (*str) { 489 case '+': 490 case '-': 491 case '=': 492 op = *str++; 493 break; 494 default: 495 pr_err("bad flag-op %c, at start of %s\n", *str, str); 496 return -EINVAL; 497 } 498 v3pr_info("op='%c'\n", op); 499 500 for (; *str ; ++str) { 501 for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) { 502 if (*str == opt_array[i].opt_char) { 503 modifiers->flags |= opt_array[i].flag; 504 break; 505 } 506 } 507 if (i < 0) { 508 pr_err("unknown flag '%c'\n", *str); 509 return -EINVAL; 510 } 511 } 512 v3pr_info("flags=0x%x\n", modifiers->flags); 513 514 /* calculate final flags, mask based upon op */ 515 switch (op) { 516 case '=': 517 /* modifiers->flags already set */ 518 modifiers->mask = 0; 519 break; 520 case '+': 521 modifiers->mask = ~0U; 522 break; 523 case '-': 524 modifiers->mask = ~modifiers->flags; 525 modifiers->flags = 0; 526 break; 527 } 528 v3pr_info("*flagsp=0x%x *maskp=0x%x\n", modifiers->flags, modifiers->mask); 529 530 return 0; 531 } 532 533 static int ddebug_exec_query(char *query_string, const char *modname) 534 { 535 struct flag_settings modifiers = {}; 536 struct ddebug_query query = {}; 537 #define MAXWORDS 9 538 int nwords, nfound; 539 char *words[MAXWORDS]; 540 541 nwords = ddebug_tokenize(query_string, words, MAXWORDS); 542 if (nwords <= 0) { 543 pr_err("tokenize failed\n"); 544 return -EINVAL; 545 } 546 /* check flags 1st (last arg) so query is pairs of spec,val */ 547 if (ddebug_parse_flags(words[nwords-1], &modifiers)) { 548 pr_err("flags parse failed\n"); 549 return -EINVAL; 550 } 551 if (ddebug_parse_query(words, nwords-1, &query, modname)) { 552 pr_err("query parse failed\n"); 553 return -EINVAL; 554 } 555 /* actually go and implement the change */ 556 nfound = ddebug_change(&query, &modifiers); 557 vpr_info_dq(&query, nfound ? "applied" : "no-match"); 558 559 return nfound; 560 } 561 562 /* handle multiple queries in query string, continue on error, return 563 last error or number of matching callsites. Module name is either 564 in param (for boot arg) or perhaps in query string. 565 */ 566 static int ddebug_exec_queries(char *query, const char *modname) 567 { 568 char *split; 569 int i, errs = 0, exitcode = 0, rc, nfound = 0; 570 571 for (i = 0; query; query = split) { 572 split = strpbrk(query, ";\n"); 573 if (split) 574 *split++ = '\0'; 575 576 query = skip_spaces(query); 577 if (!query || !*query || *query == '#') 578 continue; 579 580 vpr_info("query %d: \"%s\" mod:%s\n", i, query, modname ?: "*"); 581 582 rc = ddebug_exec_query(query, modname); 583 if (rc < 0) { 584 errs++; 585 exitcode = rc; 586 } else { 587 nfound += rc; 588 } 589 i++; 590 } 591 if (i) 592 v2pr_info("processed %d queries, with %d matches, %d errs\n", 593 i, nfound, errs); 594 595 if (exitcode) 596 return exitcode; 597 return nfound; 598 } 599 600 /* apply a new bitmap to the sys-knob's current bit-state */ 601 static int ddebug_apply_class_bitmap(const struct ddebug_class_param *dcp, 602 unsigned long *new_bits, unsigned long *old_bits) 603 { 604 #define QUERY_SIZE 128 605 char query[QUERY_SIZE]; 606 const struct ddebug_class_map *map = dcp->map; 607 int matches = 0; 608 int bi, ct; 609 610 v2pr_info("apply: 0x%lx to: 0x%lx\n", *new_bits, *old_bits); 611 612 for (bi = 0; bi < map->length; bi++) { 613 if (test_bit(bi, new_bits) == test_bit(bi, old_bits)) 614 continue; 615 616 snprintf(query, QUERY_SIZE, "class %s %c%s", map->class_names[bi], 617 test_bit(bi, new_bits) ? '+' : '-', dcp->flags); 618 619 ct = ddebug_exec_queries(query, NULL); 620 matches += ct; 621 622 v2pr_info("bit_%d: %d matches on class: %s -> 0x%lx\n", bi, 623 ct, map->class_names[bi], *new_bits); 624 } 625 return matches; 626 } 627 628 /* stub to later conditionally add "$module." prefix where not already done */ 629 #define KP_NAME(kp) kp->name 630 631 #define CLASSMAP_BITMASK(width) ((1UL << (width)) - 1) 632 633 /* accept comma-separated-list of [+-] classnames */ 634 static int param_set_dyndbg_classnames(const char *instr, const struct kernel_param *kp) 635 { 636 const struct ddebug_class_param *dcp = kp->arg; 637 const struct ddebug_class_map *map = dcp->map; 638 unsigned long curr_bits, old_bits; 639 char *cl_str, *p, *tmp; 640 int cls_id, totct = 0; 641 bool wanted; 642 643 cl_str = tmp = kstrdup(instr, GFP_KERNEL); 644 p = strchr(cl_str, '\n'); 645 if (p) 646 *p = '\0'; 647 648 /* start with previously set state-bits, then modify */ 649 curr_bits = old_bits = *dcp->bits; 650 vpr_info("\"%s\" > %s:0x%lx\n", cl_str, KP_NAME(kp), curr_bits); 651 652 for (; cl_str; cl_str = p) { 653 p = strchr(cl_str, ','); 654 if (p) 655 *p++ = '\0'; 656 657 if (*cl_str == '-') { 658 wanted = false; 659 cl_str++; 660 } else { 661 wanted = true; 662 if (*cl_str == '+') 663 cl_str++; 664 } 665 cls_id = match_string(map->class_names, map->length, cl_str); 666 if (cls_id < 0) { 667 pr_err("%s unknown to %s\n", cl_str, KP_NAME(kp)); 668 continue; 669 } 670 671 /* have one or more valid class_ids of one *_NAMES type */ 672 switch (map->map_type) { 673 case DD_CLASS_TYPE_DISJOINT_NAMES: 674 /* the +/- pertains to a single bit */ 675 if (test_bit(cls_id, &curr_bits) == wanted) { 676 v3pr_info("no change on %s\n", cl_str); 677 continue; 678 } 679 curr_bits ^= BIT(cls_id); 680 totct += ddebug_apply_class_bitmap(dcp, &curr_bits, dcp->bits); 681 *dcp->bits = curr_bits; 682 v2pr_info("%s: changed bit %d:%s\n", KP_NAME(kp), cls_id, 683 map->class_names[cls_id]); 684 break; 685 case DD_CLASS_TYPE_LEVEL_NAMES: 686 /* cls_id = N in 0..max. wanted +/- determines N or N-1 */ 687 old_bits = CLASSMAP_BITMASK(*dcp->lvl); 688 curr_bits = CLASSMAP_BITMASK(cls_id + (wanted ? 1 : 0 )); 689 690 totct += ddebug_apply_class_bitmap(dcp, &curr_bits, &old_bits); 691 *dcp->lvl = (cls_id + (wanted ? 1 : 0)); 692 v2pr_info("%s: changed bit-%d: \"%s\" %lx->%lx\n", KP_NAME(kp), cls_id, 693 map->class_names[cls_id], old_bits, curr_bits); 694 break; 695 default: 696 pr_err("illegal map-type value %d\n", map->map_type); 697 } 698 } 699 kfree(tmp); 700 vpr_info("total matches: %d\n", totct); 701 return 0; 702 } 703 704 /** 705 * param_set_dyndbg_classes - class FOO >control 706 * @instr: string echo>d to sysfs, input depends on map_type 707 * @kp: kp->arg has state: bits/lvl, map, map_type 708 * 709 * Enable/disable prdbgs by their class, as given in the arguments to 710 * DECLARE_DYNDBG_CLASSMAP. For LEVEL map-types, enforce relative 711 * levels by bitpos. 712 * 713 * Returns: 0 or <0 if error. 714 */ 715 int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) 716 { 717 const struct ddebug_class_param *dcp = kp->arg; 718 const struct ddebug_class_map *map = dcp->map; 719 unsigned long inrep, new_bits, old_bits; 720 int rc, totct = 0; 721 722 switch (map->map_type) { 723 724 case DD_CLASS_TYPE_DISJOINT_NAMES: 725 case DD_CLASS_TYPE_LEVEL_NAMES: 726 /* handle [+-]classnames list separately, we are done here */ 727 return param_set_dyndbg_classnames(instr, kp); 728 729 case DD_CLASS_TYPE_DISJOINT_BITS: 730 case DD_CLASS_TYPE_LEVEL_NUM: 731 /* numeric input, accept and fall-thru */ 732 rc = kstrtoul(instr, 0, &inrep); 733 if (rc) { 734 pr_err("expecting numeric input: %s > %s\n", instr, KP_NAME(kp)); 735 return -EINVAL; 736 } 737 break; 738 default: 739 pr_err("%s: bad map type: %d\n", KP_NAME(kp), map->map_type); 740 return -EINVAL; 741 } 742 743 /* only _BITS,_NUM (numeric) map-types get here */ 744 switch (map->map_type) { 745 case DD_CLASS_TYPE_DISJOINT_BITS: 746 /* expect bits. mask and warn if too many */ 747 if (inrep & ~CLASSMAP_BITMASK(map->length)) { 748 pr_warn("%s: input: 0x%lx exceeds mask: 0x%lx, masking\n", 749 KP_NAME(kp), inrep, CLASSMAP_BITMASK(map->length)); 750 inrep &= CLASSMAP_BITMASK(map->length); 751 } 752 v2pr_info("bits:%lx > %s\n", inrep, KP_NAME(kp)); 753 totct += ddebug_apply_class_bitmap(dcp, &inrep, dcp->bits); 754 *dcp->bits = inrep; 755 break; 756 case DD_CLASS_TYPE_LEVEL_NUM: 757 /* input is bitpos, of highest verbosity to be enabled */ 758 if (inrep > map->length) { 759 pr_warn("%s: level:%ld exceeds max:%d, clamping\n", 760 KP_NAME(kp), inrep, map->length); 761 inrep = map->length; 762 } 763 old_bits = CLASSMAP_BITMASK(*dcp->lvl); 764 new_bits = CLASSMAP_BITMASK(inrep); 765 v2pr_info("lvl:%ld bits:0x%lx > %s\n", inrep, new_bits, KP_NAME(kp)); 766 totct += ddebug_apply_class_bitmap(dcp, &new_bits, &old_bits); 767 *dcp->lvl = inrep; 768 break; 769 default: 770 pr_warn("%s: bad map type: %d\n", KP_NAME(kp), map->map_type); 771 } 772 vpr_info("%s: total matches: %d\n", KP_NAME(kp), totct); 773 return 0; 774 } 775 EXPORT_SYMBOL(param_set_dyndbg_classes); 776 777 /** 778 * param_get_dyndbg_classes - classes reader 779 * @buffer: string description of controlled bits -> classes 780 * @kp: kp->arg has state: bits, map 781 * 782 * Reads last written state, underlying prdbg state may have been 783 * altered by direct >control. Displays 0x for DISJOINT, 0-N for 784 * LEVEL Returns: #chars written or <0 on error 785 */ 786 int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp) 787 { 788 const struct ddebug_class_param *dcp = kp->arg; 789 const struct ddebug_class_map *map = dcp->map; 790 791 switch (map->map_type) { 792 793 case DD_CLASS_TYPE_DISJOINT_NAMES: 794 case DD_CLASS_TYPE_DISJOINT_BITS: 795 return scnprintf(buffer, PAGE_SIZE, "0x%lx\n", *dcp->bits); 796 797 case DD_CLASS_TYPE_LEVEL_NAMES: 798 case DD_CLASS_TYPE_LEVEL_NUM: 799 return scnprintf(buffer, PAGE_SIZE, "%d\n", *dcp->lvl); 800 default: 801 return -1; 802 } 803 } 804 EXPORT_SYMBOL(param_get_dyndbg_classes); 805 806 const struct kernel_param_ops param_ops_dyndbg_classes = { 807 .set = param_set_dyndbg_classes, 808 .get = param_get_dyndbg_classes, 809 }; 810 EXPORT_SYMBOL(param_ops_dyndbg_classes); 811 812 #define PREFIX_SIZE 128 813 814 static int remaining(int wrote) 815 { 816 if (PREFIX_SIZE - wrote > 0) 817 return PREFIX_SIZE - wrote; 818 return 0; 819 } 820 821 static char *__dynamic_emit_prefix(const struct _ddebug *desc, char *buf) 822 { 823 int pos_after_tid; 824 int pos = 0; 825 826 if (desc->flags & _DPRINTK_FLAGS_INCL_TID) { 827 if (in_interrupt()) 828 pos += snprintf(buf + pos, remaining(pos), "<intr> "); 829 else 830 pos += snprintf(buf + pos, remaining(pos), "[%d] ", 831 task_pid_vnr(current)); 832 } 833 pos_after_tid = pos; 834 if (desc->flags & _DPRINTK_FLAGS_INCL_MODNAME) 835 pos += snprintf(buf + pos, remaining(pos), "%s:", 836 desc->modname); 837 if (desc->flags & _DPRINTK_FLAGS_INCL_FUNCNAME) 838 pos += snprintf(buf + pos, remaining(pos), "%s:", 839 desc->function); 840 if (desc->flags & _DPRINTK_FLAGS_INCL_SOURCENAME) 841 pos += snprintf(buf + pos, remaining(pos), "%s:", 842 trim_prefix(desc->filename)); 843 if (desc->flags & _DPRINTK_FLAGS_INCL_LINENO) 844 pos += snprintf(buf + pos, remaining(pos), "%d:", 845 desc->lineno); 846 if (pos - pos_after_tid) 847 pos += snprintf(buf + pos, remaining(pos), " "); 848 if (pos >= PREFIX_SIZE) 849 buf[PREFIX_SIZE - 1] = '\0'; 850 851 return buf; 852 } 853 854 static inline char *dynamic_emit_prefix(struct _ddebug *desc, char *buf) 855 { 856 if (unlikely(desc->flags & _DPRINTK_FLAGS_INCL_ANY)) 857 return __dynamic_emit_prefix(desc, buf); 858 return buf; 859 } 860 861 void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...) 862 { 863 va_list args; 864 struct va_format vaf; 865 char buf[PREFIX_SIZE] = ""; 866 867 BUG_ON(!descriptor); 868 BUG_ON(!fmt); 869 870 va_start(args, fmt); 871 872 vaf.fmt = fmt; 873 vaf.va = &args; 874 875 printk(KERN_DEBUG "%s%pV", dynamic_emit_prefix(descriptor, buf), &vaf); 876 877 va_end(args); 878 } 879 EXPORT_SYMBOL(__dynamic_pr_debug); 880 881 void __dynamic_dev_dbg(struct _ddebug *descriptor, 882 const struct device *dev, const char *fmt, ...) 883 { 884 struct va_format vaf; 885 va_list args; 886 887 BUG_ON(!descriptor); 888 BUG_ON(!fmt); 889 890 va_start(args, fmt); 891 892 vaf.fmt = fmt; 893 vaf.va = &args; 894 895 if (!dev) { 896 printk(KERN_DEBUG "(NULL device *): %pV", &vaf); 897 } else { 898 char buf[PREFIX_SIZE] = ""; 899 900 dev_printk_emit(LOGLEVEL_DEBUG, dev, "%s%s %s: %pV", 901 dynamic_emit_prefix(descriptor, buf), 902 dev_driver_string(dev), dev_name(dev), 903 &vaf); 904 } 905 906 va_end(args); 907 } 908 EXPORT_SYMBOL(__dynamic_dev_dbg); 909 910 #ifdef CONFIG_NET 911 912 void __dynamic_netdev_dbg(struct _ddebug *descriptor, 913 const struct net_device *dev, const char *fmt, ...) 914 { 915 struct va_format vaf; 916 va_list args; 917 918 BUG_ON(!descriptor); 919 BUG_ON(!fmt); 920 921 va_start(args, fmt); 922 923 vaf.fmt = fmt; 924 vaf.va = &args; 925 926 if (dev && dev->dev.parent) { 927 char buf[PREFIX_SIZE] = ""; 928 929 dev_printk_emit(LOGLEVEL_DEBUG, dev->dev.parent, 930 "%s%s %s %s%s: %pV", 931 dynamic_emit_prefix(descriptor, buf), 932 dev_driver_string(dev->dev.parent), 933 dev_name(dev->dev.parent), 934 netdev_name(dev), netdev_reg_state(dev), 935 &vaf); 936 } else if (dev) { 937 printk(KERN_DEBUG "%s%s: %pV", netdev_name(dev), 938 netdev_reg_state(dev), &vaf); 939 } else { 940 printk(KERN_DEBUG "(NULL net_device): %pV", &vaf); 941 } 942 943 va_end(args); 944 } 945 EXPORT_SYMBOL(__dynamic_netdev_dbg); 946 947 #endif 948 949 #if IS_ENABLED(CONFIG_INFINIBAND) 950 951 void __dynamic_ibdev_dbg(struct _ddebug *descriptor, 952 const struct ib_device *ibdev, const char *fmt, ...) 953 { 954 struct va_format vaf; 955 va_list args; 956 957 va_start(args, fmt); 958 959 vaf.fmt = fmt; 960 vaf.va = &args; 961 962 if (ibdev && ibdev->dev.parent) { 963 char buf[PREFIX_SIZE] = ""; 964 965 dev_printk_emit(LOGLEVEL_DEBUG, ibdev->dev.parent, 966 "%s%s %s %s: %pV", 967 dynamic_emit_prefix(descriptor, buf), 968 dev_driver_string(ibdev->dev.parent), 969 dev_name(ibdev->dev.parent), 970 dev_name(&ibdev->dev), 971 &vaf); 972 } else if (ibdev) { 973 printk(KERN_DEBUG "%s: %pV", dev_name(&ibdev->dev), &vaf); 974 } else { 975 printk(KERN_DEBUG "(NULL ib_device): %pV", &vaf); 976 } 977 978 va_end(args); 979 } 980 EXPORT_SYMBOL(__dynamic_ibdev_dbg); 981 982 #endif 983 984 /* 985 * Install a noop handler to make dyndbg look like a normal kernel cli param. 986 * This avoids warnings about dyndbg being an unknown cli param when supplied 987 * by a user. 988 */ 989 static __init int dyndbg_setup(char *str) 990 { 991 return 1; 992 } 993 994 __setup("dyndbg=", dyndbg_setup); 995 996 /* 997 * File_ops->write method for <debugfs>/dynamic_debug/control. Gathers the 998 * command text from userspace, parses and executes it. 999 */ 1000 #define USER_BUF_PAGE 4096 1001 static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf, 1002 size_t len, loff_t *offp) 1003 { 1004 char *tmpbuf; 1005 int ret; 1006 1007 if (len == 0) 1008 return 0; 1009 if (len > USER_BUF_PAGE - 1) { 1010 pr_warn("expected <%d bytes into control\n", USER_BUF_PAGE); 1011 return -E2BIG; 1012 } 1013 tmpbuf = memdup_user_nul(ubuf, len); 1014 if (IS_ERR(tmpbuf)) 1015 return PTR_ERR(tmpbuf); 1016 v2pr_info("read %zu bytes from userspace\n", len); 1017 1018 ret = ddebug_exec_queries(tmpbuf, NULL); 1019 kfree(tmpbuf); 1020 if (ret < 0) 1021 return ret; 1022 1023 *offp += len; 1024 return len; 1025 } 1026 1027 /* 1028 * Set the iterator to point to the first _ddebug object 1029 * and return a pointer to that first object. Returns 1030 * NULL if there are no _ddebugs at all. 1031 */ 1032 static struct _ddebug *ddebug_iter_first(struct ddebug_iter *iter) 1033 { 1034 if (list_empty(&ddebug_tables)) { 1035 iter->table = NULL; 1036 return NULL; 1037 } 1038 iter->table = list_entry(ddebug_tables.next, 1039 struct ddebug_table, link); 1040 iter->idx = iter->table->num_ddebugs; 1041 return &iter->table->ddebugs[--iter->idx]; 1042 } 1043 1044 /* 1045 * Advance the iterator to point to the next _ddebug 1046 * object from the one the iterator currently points at, 1047 * and returns a pointer to the new _ddebug. Returns 1048 * NULL if the iterator has seen all the _ddebugs. 1049 */ 1050 static struct _ddebug *ddebug_iter_next(struct ddebug_iter *iter) 1051 { 1052 if (iter->table == NULL) 1053 return NULL; 1054 if (--iter->idx < 0) { 1055 /* iterate to next table */ 1056 if (list_is_last(&iter->table->link, &ddebug_tables)) { 1057 iter->table = NULL; 1058 return NULL; 1059 } 1060 iter->table = list_entry(iter->table->link.next, 1061 struct ddebug_table, link); 1062 iter->idx = iter->table->num_ddebugs; 1063 --iter->idx; 1064 } 1065 return &iter->table->ddebugs[iter->idx]; 1066 } 1067 1068 /* 1069 * Seq_ops start method. Called at the start of every 1070 * read() call from userspace. Takes the ddebug_lock and 1071 * seeks the seq_file's iterator to the given position. 1072 */ 1073 static void *ddebug_proc_start(struct seq_file *m, loff_t *pos) 1074 { 1075 struct ddebug_iter *iter = m->private; 1076 struct _ddebug *dp; 1077 int n = *pos; 1078 1079 mutex_lock(&ddebug_lock); 1080 1081 if (!n) 1082 return SEQ_START_TOKEN; 1083 if (n < 0) 1084 return NULL; 1085 dp = ddebug_iter_first(iter); 1086 while (dp != NULL && --n > 0) 1087 dp = ddebug_iter_next(iter); 1088 return dp; 1089 } 1090 1091 /* 1092 * Seq_ops next method. Called several times within a read() 1093 * call from userspace, with ddebug_lock held. Walks to the 1094 * next _ddebug object with a special case for the header line. 1095 */ 1096 static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos) 1097 { 1098 struct ddebug_iter *iter = m->private; 1099 struct _ddebug *dp; 1100 1101 if (p == SEQ_START_TOKEN) 1102 dp = ddebug_iter_first(iter); 1103 else 1104 dp = ddebug_iter_next(iter); 1105 ++*pos; 1106 return dp; 1107 } 1108 1109 #define class_in_range(class_id, map) \ 1110 (class_id >= map->base && class_id < map->base + map->length) 1111 1112 static const char *ddebug_class_name(struct ddebug_iter *iter, struct _ddebug *dp) 1113 { 1114 struct ddebug_class_map *map; 1115 1116 list_for_each_entry(map, &iter->table->maps, link) 1117 if (class_in_range(dp->class_id, map)) 1118 return map->class_names[dp->class_id - map->base]; 1119 1120 return NULL; 1121 } 1122 1123 /* 1124 * Seq_ops show method. Called several times within a read() 1125 * call from userspace, with ddebug_lock held. Formats the 1126 * current _ddebug as a single human-readable line, with a 1127 * special case for the header line. 1128 */ 1129 static int ddebug_proc_show(struct seq_file *m, void *p) 1130 { 1131 struct ddebug_iter *iter = m->private; 1132 struct _ddebug *dp = p; 1133 struct flagsbuf flags; 1134 char const *class; 1135 1136 if (p == SEQ_START_TOKEN) { 1137 seq_puts(m, 1138 "# filename:lineno [module]function flags format\n"); 1139 return 0; 1140 } 1141 1142 seq_printf(m, "%s:%u [%s]%s =%s \"", 1143 trim_prefix(dp->filename), dp->lineno, 1144 iter->table->mod_name, dp->function, 1145 ddebug_describe_flags(dp->flags, &flags)); 1146 seq_escape_str(m, dp->format, ESCAPE_SPACE, "\t\r\n\""); 1147 seq_puts(m, "\""); 1148 1149 if (dp->class_id != _DPRINTK_CLASS_DFLT) { 1150 class = ddebug_class_name(iter, dp); 1151 if (class) 1152 seq_printf(m, " class:%s", class); 1153 else 1154 seq_printf(m, " class unknown, _id:%d", dp->class_id); 1155 } 1156 seq_puts(m, "\n"); 1157 1158 return 0; 1159 } 1160 1161 /* 1162 * Seq_ops stop method. Called at the end of each read() 1163 * call from userspace. Drops ddebug_lock. 1164 */ 1165 static void ddebug_proc_stop(struct seq_file *m, void *p) 1166 { 1167 mutex_unlock(&ddebug_lock); 1168 } 1169 1170 static const struct seq_operations ddebug_proc_seqops = { 1171 .start = ddebug_proc_start, 1172 .next = ddebug_proc_next, 1173 .show = ddebug_proc_show, 1174 .stop = ddebug_proc_stop 1175 }; 1176 1177 static int ddebug_proc_open(struct inode *inode, struct file *file) 1178 { 1179 return seq_open_private(file, &ddebug_proc_seqops, 1180 sizeof(struct ddebug_iter)); 1181 } 1182 1183 static const struct file_operations ddebug_proc_fops = { 1184 .owner = THIS_MODULE, 1185 .open = ddebug_proc_open, 1186 .read = seq_read, 1187 .llseek = seq_lseek, 1188 .release = seq_release_private, 1189 .write = ddebug_proc_write 1190 }; 1191 1192 static const struct proc_ops proc_fops = { 1193 .proc_open = ddebug_proc_open, 1194 .proc_read = seq_read, 1195 .proc_lseek = seq_lseek, 1196 .proc_release = seq_release_private, 1197 .proc_write = ddebug_proc_write 1198 }; 1199 1200 static void ddebug_attach_module_classes(struct ddebug_table *dt, 1201 struct ddebug_class_map *classes, 1202 int num_classes) 1203 { 1204 struct ddebug_class_map *cm; 1205 int i, j, ct = 0; 1206 1207 for (cm = classes, i = 0; i < num_classes; i++, cm++) { 1208 1209 if (!strcmp(cm->mod_name, dt->mod_name)) { 1210 1211 v2pr_info("class[%d]: module:%s base:%d len:%d ty:%d\n", i, 1212 cm->mod_name, cm->base, cm->length, cm->map_type); 1213 1214 for (j = 0; j < cm->length; j++) 1215 v3pr_info(" %d: %d %s\n", j + cm->base, j, 1216 cm->class_names[j]); 1217 1218 list_add(&cm->link, &dt->maps); 1219 ct++; 1220 } 1221 } 1222 if (ct) 1223 vpr_info("module:%s attached %d classes\n", dt->mod_name, ct); 1224 } 1225 1226 /* 1227 * Allocate a new ddebug_table for the given module 1228 * and add it to the global list. 1229 */ 1230 static int ddebug_add_module(struct _ddebug_info *di, const char *modname) 1231 { 1232 struct ddebug_table *dt; 1233 1234 v3pr_info("add-module: %s.%d sites\n", modname, di->num_descs); 1235 if (!di->num_descs) { 1236 v3pr_info(" skip %s\n", modname); 1237 return 0; 1238 } 1239 1240 dt = kzalloc(sizeof(*dt), GFP_KERNEL); 1241 if (dt == NULL) { 1242 pr_err("error adding module: %s\n", modname); 1243 return -ENOMEM; 1244 } 1245 /* 1246 * For built-in modules, name lives in .rodata and is 1247 * immortal. For loaded modules, name points at the name[] 1248 * member of struct module, which lives at least as long as 1249 * this struct ddebug_table. 1250 */ 1251 dt->mod_name = modname; 1252 dt->ddebugs = di->descs; 1253 dt->num_ddebugs = di->num_descs; 1254 1255 INIT_LIST_HEAD(&dt->link); 1256 INIT_LIST_HEAD(&dt->maps); 1257 1258 if (di->classes && di->num_classes) 1259 ddebug_attach_module_classes(dt, di->classes, di->num_classes); 1260 1261 mutex_lock(&ddebug_lock); 1262 list_add_tail(&dt->link, &ddebug_tables); 1263 mutex_unlock(&ddebug_lock); 1264 1265 vpr_info("%3u debug prints in module %s\n", di->num_descs, modname); 1266 return 0; 1267 } 1268 1269 /* helper for ddebug_dyndbg_(boot|module)_param_cb */ 1270 static int ddebug_dyndbg_param_cb(char *param, char *val, 1271 const char *modname, int on_err) 1272 { 1273 char *sep; 1274 1275 sep = strchr(param, '.'); 1276 if (sep) { 1277 /* needed only for ddebug_dyndbg_boot_param_cb */ 1278 *sep = '\0'; 1279 modname = param; 1280 param = sep + 1; 1281 } 1282 if (strcmp(param, "dyndbg")) 1283 return on_err; /* determined by caller */ 1284 1285 ddebug_exec_queries((val ? val : "+p"), modname); 1286 1287 return 0; /* query failure shouldn't stop module load */ 1288 } 1289 1290 /* handle both dyndbg and $module.dyndbg params at boot */ 1291 static int ddebug_dyndbg_boot_param_cb(char *param, char *val, 1292 const char *unused, void *arg) 1293 { 1294 vpr_info("%s=\"%s\"\n", param, val); 1295 return ddebug_dyndbg_param_cb(param, val, NULL, 0); 1296 } 1297 1298 /* 1299 * modprobe foo finds foo.params in boot-args, strips "foo.", and 1300 * passes them to load_module(). This callback gets unknown params, 1301 * processes dyndbg params, rejects others. 1302 */ 1303 int ddebug_dyndbg_module_param_cb(char *param, char *val, const char *module) 1304 { 1305 vpr_info("module: %s %s=\"%s\"\n", module, param, val); 1306 return ddebug_dyndbg_param_cb(param, val, module, -ENOENT); 1307 } 1308 1309 static void ddebug_table_free(struct ddebug_table *dt) 1310 { 1311 list_del_init(&dt->link); 1312 kfree(dt); 1313 } 1314 1315 #ifdef CONFIG_MODULES 1316 1317 /* 1318 * Called in response to a module being unloaded. Removes 1319 * any ddebug_table's which point at the module. 1320 */ 1321 static int ddebug_remove_module(const char *mod_name) 1322 { 1323 struct ddebug_table *dt, *nextdt; 1324 int ret = -ENOENT; 1325 1326 mutex_lock(&ddebug_lock); 1327 list_for_each_entry_safe(dt, nextdt, &ddebug_tables, link) { 1328 if (dt->mod_name == mod_name) { 1329 ddebug_table_free(dt); 1330 ret = 0; 1331 break; 1332 } 1333 } 1334 mutex_unlock(&ddebug_lock); 1335 if (!ret) 1336 v2pr_info("removed module \"%s\"\n", mod_name); 1337 return ret; 1338 } 1339 1340 static int ddebug_module_notify(struct notifier_block *self, unsigned long val, 1341 void *data) 1342 { 1343 struct module *mod = data; 1344 int ret = 0; 1345 1346 switch (val) { 1347 case MODULE_STATE_COMING: 1348 ret = ddebug_add_module(&mod->dyndbg_info, mod->name); 1349 if (ret) 1350 WARN(1, "Failed to allocate memory: dyndbg may not work properly.\n"); 1351 break; 1352 case MODULE_STATE_GOING: 1353 ddebug_remove_module(mod->name); 1354 break; 1355 } 1356 1357 return notifier_from_errno(ret); 1358 } 1359 1360 static struct notifier_block ddebug_module_nb = { 1361 .notifier_call = ddebug_module_notify, 1362 .priority = 0, /* dynamic debug depends on jump label */ 1363 }; 1364 1365 #endif /* CONFIG_MODULES */ 1366 1367 static void ddebug_remove_all_tables(void) 1368 { 1369 mutex_lock(&ddebug_lock); 1370 while (!list_empty(&ddebug_tables)) { 1371 struct ddebug_table *dt = list_entry(ddebug_tables.next, 1372 struct ddebug_table, 1373 link); 1374 ddebug_table_free(dt); 1375 } 1376 mutex_unlock(&ddebug_lock); 1377 } 1378 1379 static __initdata int ddebug_init_success; 1380 1381 static int __init dynamic_debug_init_control(void) 1382 { 1383 struct proc_dir_entry *procfs_dir; 1384 struct dentry *debugfs_dir; 1385 1386 if (!ddebug_init_success) 1387 return -ENODEV; 1388 1389 /* Create the control file in debugfs if it is enabled */ 1390 if (debugfs_initialized()) { 1391 debugfs_dir = debugfs_create_dir("dynamic_debug", NULL); 1392 debugfs_create_file("control", 0644, debugfs_dir, NULL, 1393 &ddebug_proc_fops); 1394 } 1395 1396 /* Also create the control file in procfs */ 1397 procfs_dir = proc_mkdir("dynamic_debug", NULL); 1398 if (procfs_dir) 1399 proc_create("control", 0644, procfs_dir, &proc_fops); 1400 1401 return 0; 1402 } 1403 1404 static int __init dynamic_debug_init(void) 1405 { 1406 struct _ddebug *iter, *iter_mod_start; 1407 int ret, i, mod_sites, mod_ct; 1408 const char *modname; 1409 char *cmdline; 1410 1411 struct _ddebug_info di = { 1412 .descs = __start___dyndbg, 1413 .classes = __start___dyndbg_classes, 1414 .num_descs = __stop___dyndbg - __start___dyndbg, 1415 .num_classes = __stop___dyndbg_classes - __start___dyndbg_classes, 1416 }; 1417 1418 #ifdef CONFIG_MODULES 1419 ret = register_module_notifier(&ddebug_module_nb); 1420 if (ret) { 1421 pr_warn("Failed to register dynamic debug module notifier\n"); 1422 return ret; 1423 } 1424 #endif /* CONFIG_MODULES */ 1425 1426 if (&__start___dyndbg == &__stop___dyndbg) { 1427 if (IS_ENABLED(CONFIG_DYNAMIC_DEBUG)) { 1428 pr_warn("_ddebug table is empty in a CONFIG_DYNAMIC_DEBUG build\n"); 1429 return 1; 1430 } 1431 pr_info("Ignore empty _ddebug table in a CONFIG_DYNAMIC_DEBUG_CORE build\n"); 1432 ddebug_init_success = 1; 1433 return 0; 1434 } 1435 1436 iter = iter_mod_start = __start___dyndbg; 1437 modname = iter->modname; 1438 i = mod_sites = mod_ct = 0; 1439 1440 for (; iter < __stop___dyndbg; iter++, i++, mod_sites++) { 1441 1442 if (strcmp(modname, iter->modname)) { 1443 mod_ct++; 1444 di.num_descs = mod_sites; 1445 di.descs = iter_mod_start; 1446 ret = ddebug_add_module(&di, modname); 1447 if (ret) 1448 goto out_err; 1449 1450 mod_sites = 0; 1451 modname = iter->modname; 1452 iter_mod_start = iter; 1453 } 1454 } 1455 di.num_descs = mod_sites; 1456 di.descs = iter_mod_start; 1457 ret = ddebug_add_module(&di, modname); 1458 if (ret) 1459 goto out_err; 1460 1461 ddebug_init_success = 1; 1462 vpr_info("%d prdebugs in %d modules, %d KiB in ddebug tables, %d kiB in __dyndbg section\n", 1463 i, mod_ct, (int)((mod_ct * sizeof(struct ddebug_table)) >> 10), 1464 (int)((i * sizeof(struct _ddebug)) >> 10)); 1465 1466 if (di.num_classes) 1467 v2pr_info(" %d builtin ddebug class-maps\n", di.num_classes); 1468 1469 /* now that ddebug tables are loaded, process all boot args 1470 * again to find and activate queries given in dyndbg params. 1471 * While this has already been done for known boot params, it 1472 * ignored the unknown ones (dyndbg in particular). Reusing 1473 * parse_args avoids ad-hoc parsing. This will also attempt 1474 * to activate queries for not-yet-loaded modules, which is 1475 * slightly noisy if verbose, but harmless. 1476 */ 1477 cmdline = kstrdup(saved_command_line, GFP_KERNEL); 1478 parse_args("dyndbg params", cmdline, NULL, 1479 0, 0, 0, NULL, &ddebug_dyndbg_boot_param_cb); 1480 kfree(cmdline); 1481 return 0; 1482 1483 out_err: 1484 ddebug_remove_all_tables(); 1485 return 0; 1486 } 1487 /* Allow early initialization for boot messages via boot param */ 1488 early_initcall(dynamic_debug_init); 1489 1490 /* Debugfs setup must be done later */ 1491 fs_initcall(dynamic_debug_init_control); 1492