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Commit | Line | Data |
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e9d376f0 JB |
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. | |
8ba6ebf5 | 10 | * Copyright (C) 2011 Bart Van Assche. All Rights Reserved. |
e9d376f0 JB |
11 | */ |
12 | ||
4ad275e5 JP |
13 | #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__ |
14 | ||
e9d376f0 JB |
15 | #include <linux/kernel.h> |
16 | #include <linux/module.h> | |
17 | #include <linux/moduleparam.h> | |
18 | #include <linux/kallsyms.h> | |
e9d376f0 JB |
19 | #include <linux/types.h> |
20 | #include <linux/mutex.h> | |
21 | #include <linux/proc_fs.h> | |
22 | #include <linux/seq_file.h> | |
23 | #include <linux/list.h> | |
24 | #include <linux/sysctl.h> | |
25 | #include <linux/ctype.h> | |
e7d2860b | 26 | #include <linux/string.h> |
e9d376f0 JB |
27 | #include <linux/uaccess.h> |
28 | #include <linux/dynamic_debug.h> | |
29 | #include <linux/debugfs.h> | |
5a0e3ad6 | 30 | #include <linux/slab.h> |
52159d98 | 31 | #include <linux/jump_label.h> |
8ba6ebf5 | 32 | #include <linux/hardirq.h> |
e8d9792a | 33 | #include <linux/sched.h> |
cbc46635 | 34 | #include <linux/device.h> |
ffa10cb4 | 35 | #include <linux/netdevice.h> |
e9d376f0 JB |
36 | |
37 | extern struct _ddebug __start___verbose[]; | |
38 | extern struct _ddebug __stop___verbose[]; | |
39 | ||
e9d376f0 JB |
40 | struct ddebug_table { |
41 | struct list_head link; | |
42 | char *mod_name; | |
43 | unsigned int num_ddebugs; | |
e9d376f0 JB |
44 | struct _ddebug *ddebugs; |
45 | }; | |
46 | ||
47 | struct ddebug_query { | |
48 | const char *filename; | |
49 | const char *module; | |
50 | const char *function; | |
51 | const char *format; | |
52 | unsigned int first_lineno, last_lineno; | |
53 | }; | |
54 | ||
55 | struct ddebug_iter { | |
56 | struct ddebug_table *table; | |
57 | unsigned int idx; | |
58 | }; | |
59 | ||
60 | static DEFINE_MUTEX(ddebug_lock); | |
61 | static LIST_HEAD(ddebug_tables); | |
62 | static int verbose = 0; | |
74df138d | 63 | module_param(verbose, int, 0644); |
e9d376f0 JB |
64 | |
65 | /* Return the last part of a pathname */ | |
66 | static inline const char *basename(const char *path) | |
67 | { | |
68 | const char *tail = strrchr(path, '/'); | |
69 | return tail ? tail+1 : path; | |
70 | } | |
71 | ||
2b678319 JC |
72 | /* Return the path relative to source root */ |
73 | static inline const char *trim_prefix(const char *path) | |
74 | { | |
75 | int skip = strlen(__FILE__) - strlen("lib/dynamic_debug.c"); | |
76 | ||
77 | if (strncmp(path, __FILE__, skip)) | |
78 | skip = 0; /* prefix mismatch, don't skip */ | |
79 | ||
80 | return path + skip; | |
81 | } | |
82 | ||
8ba6ebf5 BVA |
83 | static struct { unsigned flag:8; char opt_char; } opt_array[] = { |
84 | { _DPRINTK_FLAGS_PRINT, 'p' }, | |
85 | { _DPRINTK_FLAGS_INCL_MODNAME, 'm' }, | |
86 | { _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' }, | |
87 | { _DPRINTK_FLAGS_INCL_LINENO, 'l' }, | |
88 | { _DPRINTK_FLAGS_INCL_TID, 't' }, | |
5ca7d2a6 | 89 | { _DPRINTK_FLAGS_NONE, '_' }, |
8ba6ebf5 BVA |
90 | }; |
91 | ||
e9d376f0 JB |
92 | /* format a string into buf[] which describes the _ddebug's flags */ |
93 | static char *ddebug_describe_flags(struct _ddebug *dp, char *buf, | |
94 | size_t maxlen) | |
95 | { | |
96 | char *p = buf; | |
8ba6ebf5 | 97 | int i; |
e9d376f0 | 98 | |
5ca7d2a6 | 99 | BUG_ON(maxlen < 6); |
8ba6ebf5 BVA |
100 | for (i = 0; i < ARRAY_SIZE(opt_array); ++i) |
101 | if (dp->flags & opt_array[i].flag) | |
102 | *p++ = opt_array[i].opt_char; | |
e9d376f0 | 103 | if (p == buf) |
5ca7d2a6 | 104 | *p++ = '_'; |
e9d376f0 JB |
105 | *p = '\0'; |
106 | ||
107 | return buf; | |
108 | } | |
109 | ||
b8ccd5de JC |
110 | #define vpr_info(fmt, ...) \ |
111 | if (verbose) do { pr_info(fmt, ##__VA_ARGS__); } while (0) | |
112 | ||
113 | #define vpr_info_dq(q, msg) \ | |
114 | do { \ | |
115 | /* trim last char off format print */ \ | |
116 | vpr_info("%s: func=\"%s\" file=\"%s\" " \ | |
117 | "module=\"%s\" format=\"%.*s\" " \ | |
118 | "lineno=%u-%u", \ | |
119 | msg, \ | |
120 | q->function ? q->function : "", \ | |
121 | q->filename ? q->filename : "", \ | |
122 | q->module ? q->module : "", \ | |
123 | (int)(q->format ? strlen(q->format) - 1 : 0), \ | |
124 | q->format ? q->format : "", \ | |
125 | q->first_lineno, q->last_lineno); \ | |
574b3725 JC |
126 | } while (0) |
127 | ||
e9d376f0 | 128 | /* |
85f7f6c0 JC |
129 | * Search the tables for _ddebug's which match the given `query' and |
130 | * apply the `flags' and `mask' to them. Returns number of matching | |
131 | * callsites, normally the same as number of changes. If verbose, | |
132 | * logs the changes. Takes ddebug_lock. | |
e9d376f0 | 133 | */ |
85f7f6c0 JC |
134 | static int ddebug_change(const struct ddebug_query *query, |
135 | unsigned int flags, unsigned int mask) | |
e9d376f0 JB |
136 | { |
137 | int i; | |
138 | struct ddebug_table *dt; | |
139 | unsigned int newflags; | |
140 | unsigned int nfound = 0; | |
5ca7d2a6 | 141 | char flagbuf[10]; |
e9d376f0 JB |
142 | |
143 | /* search for matching ddebugs */ | |
144 | mutex_lock(&ddebug_lock); | |
145 | list_for_each_entry(dt, &ddebug_tables, link) { | |
146 | ||
147 | /* match against the module name */ | |
d6a238d2 | 148 | if (query->module && strcmp(query->module, dt->mod_name)) |
e9d376f0 JB |
149 | continue; |
150 | ||
151 | for (i = 0 ; i < dt->num_ddebugs ; i++) { | |
152 | struct _ddebug *dp = &dt->ddebugs[i]; | |
153 | ||
154 | /* match against the source filename */ | |
d6a238d2 | 155 | if (query->filename && |
e9d376f0 | 156 | strcmp(query->filename, dp->filename) && |
2b678319 JC |
157 | strcmp(query->filename, basename(dp->filename)) && |
158 | strcmp(query->filename, trim_prefix(dp->filename))) | |
e9d376f0 JB |
159 | continue; |
160 | ||
161 | /* match against the function */ | |
d6a238d2 | 162 | if (query->function && |
e9d376f0 JB |
163 | strcmp(query->function, dp->function)) |
164 | continue; | |
165 | ||
166 | /* match against the format */ | |
d6a238d2 JC |
167 | if (query->format && |
168 | !strstr(dp->format, query->format)) | |
e9d376f0 JB |
169 | continue; |
170 | ||
171 | /* match against the line number range */ | |
172 | if (query->first_lineno && | |
173 | dp->lineno < query->first_lineno) | |
174 | continue; | |
175 | if (query->last_lineno && | |
176 | dp->lineno > query->last_lineno) | |
177 | continue; | |
178 | ||
179 | nfound++; | |
180 | ||
181 | newflags = (dp->flags & mask) | flags; | |
182 | if (newflags == dp->flags) | |
183 | continue; | |
e9d376f0 | 184 | dp->flags = newflags; |
b8ccd5de JC |
185 | vpr_info("changed %s:%d [%s]%s =%s\n", |
186 | trim_prefix(dp->filename), dp->lineno, | |
187 | dt->mod_name, dp->function, | |
188 | ddebug_describe_flags(dp, flagbuf, | |
189 | sizeof(flagbuf))); | |
e9d376f0 JB |
190 | } |
191 | } | |
192 | mutex_unlock(&ddebug_lock); | |
193 | ||
194 | if (!nfound && verbose) | |
4ad275e5 | 195 | pr_info("no matches for query\n"); |
85f7f6c0 JC |
196 | |
197 | return nfound; | |
e9d376f0 JB |
198 | } |
199 | ||
e9d376f0 JB |
200 | /* |
201 | * Split the buffer `buf' into space-separated words. | |
9898abb3 GB |
202 | * Handles simple " and ' quoting, i.e. without nested, |
203 | * embedded or escaped \". Return the number of words | |
204 | * or <0 on error. | |
e9d376f0 JB |
205 | */ |
206 | static int ddebug_tokenize(char *buf, char *words[], int maxwords) | |
207 | { | |
208 | int nwords = 0; | |
209 | ||
9898abb3 GB |
210 | while (*buf) { |
211 | char *end; | |
212 | ||
213 | /* Skip leading whitespace */ | |
e7d2860b | 214 | buf = skip_spaces(buf); |
9898abb3 GB |
215 | if (!*buf) |
216 | break; /* oh, it was trailing whitespace */ | |
8bd6026e JC |
217 | if (*buf == '#') |
218 | break; /* token starts comment, skip rest of line */ | |
9898abb3 | 219 | |
07100be7 | 220 | /* find `end' of word, whitespace separated or quoted */ |
9898abb3 GB |
221 | if (*buf == '"' || *buf == '\'') { |
222 | int quote = *buf++; | |
223 | for (end = buf ; *end && *end != quote ; end++) | |
224 | ; | |
225 | if (!*end) | |
226 | return -EINVAL; /* unclosed quote */ | |
227 | } else { | |
228 | for (end = buf ; *end && !isspace(*end) ; end++) | |
229 | ; | |
230 | BUG_ON(end == buf); | |
231 | } | |
9898abb3 | 232 | |
07100be7 | 233 | /* `buf' is start of word, `end' is one past its end */ |
9898abb3 GB |
234 | if (nwords == maxwords) |
235 | return -EINVAL; /* ran out of words[] before bytes */ | |
236 | if (*end) | |
237 | *end++ = '\0'; /* terminate the word */ | |
238 | words[nwords++] = buf; | |
239 | buf = end; | |
240 | } | |
e9d376f0 JB |
241 | |
242 | if (verbose) { | |
243 | int i; | |
4ad275e5 | 244 | pr_info("split into words:"); |
e9d376f0 | 245 | for (i = 0 ; i < nwords ; i++) |
4ad275e5 JP |
246 | pr_cont(" \"%s\"", words[i]); |
247 | pr_cont("\n"); | |
e9d376f0 JB |
248 | } |
249 | ||
250 | return nwords; | |
251 | } | |
252 | ||
253 | /* | |
254 | * Parse a single line number. Note that the empty string "" | |
255 | * is treated as a special case and converted to zero, which | |
256 | * is later treated as a "don't care" value. | |
257 | */ | |
258 | static inline int parse_lineno(const char *str, unsigned int *val) | |
259 | { | |
260 | char *end = NULL; | |
261 | BUG_ON(str == NULL); | |
262 | if (*str == '\0') { | |
263 | *val = 0; | |
264 | return 0; | |
265 | } | |
266 | *val = simple_strtoul(str, &end, 10); | |
267 | return end == NULL || end == str || *end != '\0' ? -EINVAL : 0; | |
268 | } | |
269 | ||
270 | /* | |
271 | * Undo octal escaping in a string, inplace. This is useful to | |
272 | * allow the user to express a query which matches a format | |
273 | * containing embedded spaces. | |
274 | */ | |
275 | #define isodigit(c) ((c) >= '0' && (c) <= '7') | |
276 | static char *unescape(char *str) | |
277 | { | |
278 | char *in = str; | |
279 | char *out = str; | |
280 | ||
281 | while (*in) { | |
282 | if (*in == '\\') { | |
283 | if (in[1] == '\\') { | |
284 | *out++ = '\\'; | |
285 | in += 2; | |
286 | continue; | |
287 | } else if (in[1] == 't') { | |
288 | *out++ = '\t'; | |
289 | in += 2; | |
290 | continue; | |
291 | } else if (in[1] == 'n') { | |
292 | *out++ = '\n'; | |
293 | in += 2; | |
294 | continue; | |
295 | } else if (isodigit(in[1]) && | |
296 | isodigit(in[2]) && | |
297 | isodigit(in[3])) { | |
298 | *out++ = ((in[1] - '0')<<6) | | |
299 | ((in[2] - '0')<<3) | | |
300 | (in[3] - '0'); | |
301 | in += 4; | |
302 | continue; | |
303 | } | |
304 | } | |
305 | *out++ = *in++; | |
306 | } | |
307 | *out = '\0'; | |
308 | ||
309 | return str; | |
310 | } | |
311 | ||
820874c7 JC |
312 | static int check_set(const char **dest, char *src, char *name) |
313 | { | |
314 | int rc = 0; | |
315 | ||
316 | if (*dest) { | |
317 | rc = -EINVAL; | |
318 | pr_err("match-spec:%s val:%s overridden by %s", | |
319 | name, *dest, src); | |
320 | } | |
321 | *dest = src; | |
322 | return rc; | |
323 | } | |
324 | ||
e9d376f0 JB |
325 | /* |
326 | * Parse words[] as a ddebug query specification, which is a series | |
327 | * of (keyword, value) pairs chosen from these possibilities: | |
328 | * | |
329 | * func <function-name> | |
330 | * file <full-pathname> | |
331 | * file <base-filename> | |
332 | * module <module-name> | |
333 | * format <escaped-string-to-find-in-format> | |
334 | * line <lineno> | |
335 | * line <first-lineno>-<last-lineno> // where either may be empty | |
820874c7 JC |
336 | * |
337 | * Only 1 of each type is allowed. | |
338 | * Returns 0 on success, <0 on error. | |
e9d376f0 JB |
339 | */ |
340 | static int ddebug_parse_query(char *words[], int nwords, | |
341 | struct ddebug_query *query) | |
342 | { | |
343 | unsigned int i; | |
820874c7 | 344 | int rc; |
e9d376f0 JB |
345 | |
346 | /* check we have an even number of words */ | |
347 | if (nwords % 2 != 0) | |
348 | return -EINVAL; | |
349 | memset(query, 0, sizeof(*query)); | |
350 | ||
351 | for (i = 0 ; i < nwords ; i += 2) { | |
352 | if (!strcmp(words[i], "func")) | |
820874c7 | 353 | rc = check_set(&query->function, words[i+1], "func"); |
e9d376f0 | 354 | else if (!strcmp(words[i], "file")) |
820874c7 | 355 | rc = check_set(&query->filename, words[i+1], "file"); |
e9d376f0 | 356 | else if (!strcmp(words[i], "module")) |
820874c7 | 357 | rc = check_set(&query->module, words[i+1], "module"); |
e9d376f0 | 358 | else if (!strcmp(words[i], "format")) |
820874c7 JC |
359 | rc = check_set(&query->format, unescape(words[i+1]), |
360 | "format"); | |
e9d376f0 JB |
361 | else if (!strcmp(words[i], "line")) { |
362 | char *first = words[i+1]; | |
363 | char *last = strchr(first, '-'); | |
820874c7 JC |
364 | if (query->first_lineno || query->last_lineno) { |
365 | pr_err("match-spec:line given 2 times\n"); | |
366 | return -EINVAL; | |
367 | } | |
e9d376f0 JB |
368 | if (last) |
369 | *last++ = '\0'; | |
370 | if (parse_lineno(first, &query->first_lineno) < 0) | |
371 | return -EINVAL; | |
820874c7 | 372 | if (last) { |
e9d376f0 | 373 | /* range <first>-<last> */ |
820874c7 JC |
374 | if (parse_lineno(last, &query->last_lineno) |
375 | < query->first_lineno) { | |
376 | pr_err("last-line < 1st-line\n"); | |
e9d376f0 | 377 | return -EINVAL; |
820874c7 | 378 | } |
e9d376f0 JB |
379 | } else { |
380 | query->last_lineno = query->first_lineno; | |
381 | } | |
382 | } else { | |
ae27f86a | 383 | pr_err("unknown keyword \"%s\"\n", words[i]); |
e9d376f0 JB |
384 | return -EINVAL; |
385 | } | |
820874c7 JC |
386 | if (rc) |
387 | return rc; | |
e9d376f0 | 388 | } |
574b3725 | 389 | vpr_info_dq(query, "parsed"); |
e9d376f0 JB |
390 | return 0; |
391 | } | |
392 | ||
393 | /* | |
394 | * Parse `str' as a flags specification, format [-+=][p]+. | |
395 | * Sets up *maskp and *flagsp to be used when changing the | |
396 | * flags fields of matched _ddebug's. Returns 0 on success | |
397 | * or <0 on error. | |
398 | */ | |
399 | static int ddebug_parse_flags(const char *str, unsigned int *flagsp, | |
400 | unsigned int *maskp) | |
401 | { | |
402 | unsigned flags = 0; | |
8ba6ebf5 | 403 | int op = '=', i; |
e9d376f0 JB |
404 | |
405 | switch (*str) { | |
406 | case '+': | |
407 | case '-': | |
408 | case '=': | |
409 | op = *str++; | |
410 | break; | |
411 | default: | |
412 | return -EINVAL; | |
413 | } | |
b8ccd5de | 414 | vpr_info("op='%c'\n", op); |
e9d376f0 JB |
415 | |
416 | for ( ; *str ; ++str) { | |
8ba6ebf5 BVA |
417 | for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) { |
418 | if (*str == opt_array[i].opt_char) { | |
419 | flags |= opt_array[i].flag; | |
420 | break; | |
421 | } | |
e9d376f0 | 422 | } |
8ba6ebf5 BVA |
423 | if (i < 0) |
424 | return -EINVAL; | |
e9d376f0 | 425 | } |
b8ccd5de | 426 | vpr_info("flags=0x%x\n", flags); |
e9d376f0 JB |
427 | |
428 | /* calculate final *flagsp, *maskp according to mask and op */ | |
429 | switch (op) { | |
430 | case '=': | |
431 | *maskp = 0; | |
432 | *flagsp = flags; | |
433 | break; | |
434 | case '+': | |
435 | *maskp = ~0U; | |
436 | *flagsp = flags; | |
437 | break; | |
438 | case '-': | |
439 | *maskp = ~flags; | |
440 | *flagsp = 0; | |
441 | break; | |
442 | } | |
b8ccd5de | 443 | vpr_info("*flagsp=0x%x *maskp=0x%x\n", *flagsp, *maskp); |
e9d376f0 JB |
444 | return 0; |
445 | } | |
446 | ||
fd89cfb8 TR |
447 | static int ddebug_exec_query(char *query_string) |
448 | { | |
449 | unsigned int flags = 0, mask = 0; | |
450 | struct ddebug_query query; | |
451 | #define MAXWORDS 9 | |
85f7f6c0 | 452 | int nwords, nfound; |
fd89cfb8 TR |
453 | char *words[MAXWORDS]; |
454 | ||
455 | nwords = ddebug_tokenize(query_string, words, MAXWORDS); | |
456 | if (nwords <= 0) | |
457 | return -EINVAL; | |
458 | if (ddebug_parse_query(words, nwords-1, &query)) | |
459 | return -EINVAL; | |
460 | if (ddebug_parse_flags(words[nwords-1], &flags, &mask)) | |
461 | return -EINVAL; | |
462 | ||
463 | /* actually go and implement the change */ | |
85f7f6c0 JC |
464 | nfound = ddebug_change(&query, flags, mask); |
465 | vpr_info_dq((&query), (nfound) ? "applied" : "no-match"); | |
466 | ||
467 | return nfound; | |
468 | } | |
469 | ||
470 | /* handle multiple queries in query string, continue on error, return | |
471 | last error or number of matching callsites. Module name is either | |
472 | in param (for boot arg) or perhaps in query string. | |
473 | */ | |
474 | static int ddebug_exec_queries(char *query) | |
475 | { | |
476 | char *split; | |
477 | int i, errs = 0, exitcode = 0, rc, nfound = 0; | |
478 | ||
479 | for (i = 0; query; query = split) { | |
480 | split = strpbrk(query, ";\n"); | |
481 | if (split) | |
482 | *split++ = '\0'; | |
483 | ||
484 | query = skip_spaces(query); | |
485 | if (!query || !*query || *query == '#') | |
486 | continue; | |
487 | ||
b8ccd5de | 488 | vpr_info("query %d: \"%s\"\n", i, query); |
85f7f6c0 JC |
489 | |
490 | rc = ddebug_exec_query(query); | |
491 | if (rc < 0) { | |
492 | errs++; | |
493 | exitcode = rc; | |
494 | } else | |
495 | nfound += rc; | |
496 | i++; | |
497 | } | |
b8ccd5de | 498 | vpr_info("processed %d queries, with %d matches, %d errs\n", |
85f7f6c0 JC |
499 | i, nfound, errs); |
500 | ||
501 | if (exitcode) | |
502 | return exitcode; | |
503 | return nfound; | |
fd89cfb8 TR |
504 | } |
505 | ||
431625da JB |
506 | #define PREFIX_SIZE 64 |
507 | ||
508 | static int remaining(int wrote) | |
509 | { | |
510 | if (PREFIX_SIZE - wrote > 0) | |
511 | return PREFIX_SIZE - wrote; | |
512 | return 0; | |
513 | } | |
514 | ||
515 | static char *dynamic_emit_prefix(const struct _ddebug *desc, char *buf) | |
8ba6ebf5 | 516 | { |
431625da JB |
517 | int pos_after_tid; |
518 | int pos = 0; | |
8ba6ebf5 | 519 | |
431625da JB |
520 | pos += snprintf(buf + pos, remaining(pos), "%s", KERN_DEBUG); |
521 | if (desc->flags & _DPRINTK_FLAGS_INCL_TID) { | |
8ba6ebf5 | 522 | if (in_interrupt()) |
431625da JB |
523 | pos += snprintf(buf + pos, remaining(pos), "%s ", |
524 | "<intr>"); | |
8ba6ebf5 | 525 | else |
431625da JB |
526 | pos += snprintf(buf + pos, remaining(pos), "[%d] ", |
527 | task_pid_vnr(current)); | |
8ba6ebf5 | 528 | } |
431625da JB |
529 | pos_after_tid = pos; |
530 | if (desc->flags & _DPRINTK_FLAGS_INCL_MODNAME) | |
531 | pos += snprintf(buf + pos, remaining(pos), "%s:", | |
532 | desc->modname); | |
533 | if (desc->flags & _DPRINTK_FLAGS_INCL_FUNCNAME) | |
534 | pos += snprintf(buf + pos, remaining(pos), "%s:", | |
535 | desc->function); | |
536 | if (desc->flags & _DPRINTK_FLAGS_INCL_LINENO) | |
07100be7 JC |
537 | pos += snprintf(buf + pos, remaining(pos), "%d:", |
538 | desc->lineno); | |
431625da JB |
539 | if (pos - pos_after_tid) |
540 | pos += snprintf(buf + pos, remaining(pos), " "); | |
541 | if (pos >= PREFIX_SIZE) | |
542 | buf[PREFIX_SIZE - 1] = '\0'; | |
6c2140ee | 543 | |
431625da | 544 | return buf; |
6c2140ee JP |
545 | } |
546 | ||
8ba6ebf5 BVA |
547 | int __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...) |
548 | { | |
549 | va_list args; | |
550 | int res; | |
431625da JB |
551 | struct va_format vaf; |
552 | char buf[PREFIX_SIZE]; | |
8ba6ebf5 BVA |
553 | |
554 | BUG_ON(!descriptor); | |
555 | BUG_ON(!fmt); | |
556 | ||
557 | va_start(args, fmt); | |
431625da JB |
558 | vaf.fmt = fmt; |
559 | vaf.va = &args; | |
560 | res = printk("%s%pV", dynamic_emit_prefix(descriptor, buf), &vaf); | |
8ba6ebf5 BVA |
561 | va_end(args); |
562 | ||
563 | return res; | |
564 | } | |
565 | EXPORT_SYMBOL(__dynamic_pr_debug); | |
566 | ||
cbc46635 JP |
567 | int __dynamic_dev_dbg(struct _ddebug *descriptor, |
568 | const struct device *dev, const char *fmt, ...) | |
569 | { | |
570 | struct va_format vaf; | |
571 | va_list args; | |
572 | int res; | |
431625da | 573 | char buf[PREFIX_SIZE]; |
cbc46635 JP |
574 | |
575 | BUG_ON(!descriptor); | |
576 | BUG_ON(!fmt); | |
577 | ||
578 | va_start(args, fmt); | |
cbc46635 JP |
579 | vaf.fmt = fmt; |
580 | vaf.va = &args; | |
431625da | 581 | res = __dev_printk(dynamic_emit_prefix(descriptor, buf), dev, &vaf); |
cbc46635 JP |
582 | va_end(args); |
583 | ||
584 | return res; | |
585 | } | |
586 | EXPORT_SYMBOL(__dynamic_dev_dbg); | |
587 | ||
0feefd97 JB |
588 | #ifdef CONFIG_NET |
589 | ||
ffa10cb4 JB |
590 | int __dynamic_netdev_dbg(struct _ddebug *descriptor, |
591 | const struct net_device *dev, const char *fmt, ...) | |
592 | { | |
593 | struct va_format vaf; | |
594 | va_list args; | |
595 | int res; | |
431625da | 596 | char buf[PREFIX_SIZE]; |
ffa10cb4 JB |
597 | |
598 | BUG_ON(!descriptor); | |
599 | BUG_ON(!fmt); | |
600 | ||
601 | va_start(args, fmt); | |
ffa10cb4 JB |
602 | vaf.fmt = fmt; |
603 | vaf.va = &args; | |
431625da | 604 | res = __netdev_printk(dynamic_emit_prefix(descriptor, buf), dev, &vaf); |
ffa10cb4 JB |
605 | va_end(args); |
606 | ||
607 | return res; | |
608 | } | |
609 | EXPORT_SYMBOL(__dynamic_netdev_dbg); | |
610 | ||
0feefd97 JB |
611 | #endif |
612 | ||
bc757f6f JC |
613 | #define DDEBUG_STRING_SIZE 1024 |
614 | static __initdata char ddebug_setup_string[DDEBUG_STRING_SIZE]; | |
615 | ||
a648ec05 TR |
616 | static __init int ddebug_setup_query(char *str) |
617 | { | |
bc757f6f | 618 | if (strlen(str) >= DDEBUG_STRING_SIZE) { |
4ad275e5 | 619 | pr_warn("ddebug boot param string too large\n"); |
a648ec05 TR |
620 | return 0; |
621 | } | |
bc757f6f | 622 | strlcpy(ddebug_setup_string, str, DDEBUG_STRING_SIZE); |
a648ec05 TR |
623 | return 1; |
624 | } | |
625 | ||
626 | __setup("ddebug_query=", ddebug_setup_query); | |
627 | ||
e9d376f0 JB |
628 | /* |
629 | * File_ops->write method for <debugfs>/dynamic_debug/conrol. Gathers the | |
630 | * command text from userspace, parses and executes it. | |
631 | */ | |
7281491c | 632 | #define USER_BUF_PAGE 4096 |
e9d376f0 JB |
633 | static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf, |
634 | size_t len, loff_t *offp) | |
635 | { | |
7281491c | 636 | char *tmpbuf; |
fd89cfb8 | 637 | int ret; |
e9d376f0 JB |
638 | |
639 | if (len == 0) | |
640 | return 0; | |
7281491c JC |
641 | if (len > USER_BUF_PAGE - 1) { |
642 | pr_warn("expected <%d bytes into control\n", USER_BUF_PAGE); | |
e9d376f0 | 643 | return -E2BIG; |
7281491c JC |
644 | } |
645 | tmpbuf = kmalloc(len + 1, GFP_KERNEL); | |
646 | if (!tmpbuf) | |
647 | return -ENOMEM; | |
648 | if (copy_from_user(tmpbuf, ubuf, len)) { | |
649 | kfree(tmpbuf); | |
e9d376f0 | 650 | return -EFAULT; |
7281491c | 651 | } |
e9d376f0 | 652 | tmpbuf[len] = '\0'; |
b8ccd5de | 653 | vpr_info("read %d bytes from userspace\n", (int)len); |
e9d376f0 | 654 | |
85f7f6c0 | 655 | ret = ddebug_exec_queries(tmpbuf); |
7281491c | 656 | kfree(tmpbuf); |
85f7f6c0 | 657 | if (ret < 0) |
fd89cfb8 | 658 | return ret; |
e9d376f0 JB |
659 | |
660 | *offp += len; | |
661 | return len; | |
662 | } | |
663 | ||
664 | /* | |
665 | * Set the iterator to point to the first _ddebug object | |
666 | * and return a pointer to that first object. Returns | |
667 | * NULL if there are no _ddebugs at all. | |
668 | */ | |
669 | static struct _ddebug *ddebug_iter_first(struct ddebug_iter *iter) | |
670 | { | |
671 | if (list_empty(&ddebug_tables)) { | |
672 | iter->table = NULL; | |
673 | iter->idx = 0; | |
674 | return NULL; | |
675 | } | |
676 | iter->table = list_entry(ddebug_tables.next, | |
677 | struct ddebug_table, link); | |
678 | iter->idx = 0; | |
679 | return &iter->table->ddebugs[iter->idx]; | |
680 | } | |
681 | ||
682 | /* | |
683 | * Advance the iterator to point to the next _ddebug | |
684 | * object from the one the iterator currently points at, | |
685 | * and returns a pointer to the new _ddebug. Returns | |
686 | * NULL if the iterator has seen all the _ddebugs. | |
687 | */ | |
688 | static struct _ddebug *ddebug_iter_next(struct ddebug_iter *iter) | |
689 | { | |
690 | if (iter->table == NULL) | |
691 | return NULL; | |
692 | if (++iter->idx == iter->table->num_ddebugs) { | |
693 | /* iterate to next table */ | |
694 | iter->idx = 0; | |
695 | if (list_is_last(&iter->table->link, &ddebug_tables)) { | |
696 | iter->table = NULL; | |
697 | return NULL; | |
698 | } | |
699 | iter->table = list_entry(iter->table->link.next, | |
700 | struct ddebug_table, link); | |
701 | } | |
702 | return &iter->table->ddebugs[iter->idx]; | |
703 | } | |
704 | ||
705 | /* | |
706 | * Seq_ops start method. Called at the start of every | |
707 | * read() call from userspace. Takes the ddebug_lock and | |
708 | * seeks the seq_file's iterator to the given position. | |
709 | */ | |
710 | static void *ddebug_proc_start(struct seq_file *m, loff_t *pos) | |
711 | { | |
712 | struct ddebug_iter *iter = m->private; | |
713 | struct _ddebug *dp; | |
714 | int n = *pos; | |
715 | ||
b8ccd5de | 716 | vpr_info("called m=%p *pos=%lld\n", m, (unsigned long long)*pos); |
e9d376f0 JB |
717 | |
718 | mutex_lock(&ddebug_lock); | |
719 | ||
720 | if (!n) | |
721 | return SEQ_START_TOKEN; | |
722 | if (n < 0) | |
723 | return NULL; | |
724 | dp = ddebug_iter_first(iter); | |
725 | while (dp != NULL && --n > 0) | |
726 | dp = ddebug_iter_next(iter); | |
727 | return dp; | |
728 | } | |
729 | ||
730 | /* | |
731 | * Seq_ops next method. Called several times within a read() | |
732 | * call from userspace, with ddebug_lock held. Walks to the | |
733 | * next _ddebug object with a special case for the header line. | |
734 | */ | |
735 | static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos) | |
736 | { | |
737 | struct ddebug_iter *iter = m->private; | |
738 | struct _ddebug *dp; | |
739 | ||
b8ccd5de JC |
740 | vpr_info("called m=%p p=%p *pos=%lld\n", |
741 | m, p, (unsigned long long)*pos); | |
e9d376f0 JB |
742 | |
743 | if (p == SEQ_START_TOKEN) | |
744 | dp = ddebug_iter_first(iter); | |
745 | else | |
746 | dp = ddebug_iter_next(iter); | |
747 | ++*pos; | |
748 | return dp; | |
749 | } | |
750 | ||
751 | /* | |
752 | * Seq_ops show method. Called several times within a read() | |
753 | * call from userspace, with ddebug_lock held. Formats the | |
754 | * current _ddebug as a single human-readable line, with a | |
755 | * special case for the header line. | |
756 | */ | |
757 | static int ddebug_proc_show(struct seq_file *m, void *p) | |
758 | { | |
759 | struct ddebug_iter *iter = m->private; | |
760 | struct _ddebug *dp = p; | |
5ca7d2a6 | 761 | char flagsbuf[10]; |
e9d376f0 | 762 | |
b8ccd5de | 763 | vpr_info("called m=%p p=%p\n", m, p); |
e9d376f0 JB |
764 | |
765 | if (p == SEQ_START_TOKEN) { | |
766 | seq_puts(m, | |
767 | "# filename:lineno [module]function flags format\n"); | |
768 | return 0; | |
769 | } | |
770 | ||
5ca7d2a6 | 771 | seq_printf(m, "%s:%u [%s]%s =%s \"", |
2b678319 | 772 | trim_prefix(dp->filename), dp->lineno, |
5ca7d2a6 JC |
773 | iter->table->mod_name, dp->function, |
774 | ddebug_describe_flags(dp, flagsbuf, sizeof(flagsbuf))); | |
e9d376f0 JB |
775 | seq_escape(m, dp->format, "\t\r\n\""); |
776 | seq_puts(m, "\"\n"); | |
777 | ||
778 | return 0; | |
779 | } | |
780 | ||
781 | /* | |
782 | * Seq_ops stop method. Called at the end of each read() | |
783 | * call from userspace. Drops ddebug_lock. | |
784 | */ | |
785 | static void ddebug_proc_stop(struct seq_file *m, void *p) | |
786 | { | |
b8ccd5de | 787 | vpr_info("called m=%p p=%p\n", m, p); |
e9d376f0 JB |
788 | mutex_unlock(&ddebug_lock); |
789 | } | |
790 | ||
791 | static const struct seq_operations ddebug_proc_seqops = { | |
792 | .start = ddebug_proc_start, | |
793 | .next = ddebug_proc_next, | |
794 | .show = ddebug_proc_show, | |
795 | .stop = ddebug_proc_stop | |
796 | }; | |
797 | ||
798 | /* | |
07100be7 JC |
799 | * File_ops->open method for <debugfs>/dynamic_debug/control. Does |
800 | * the seq_file setup dance, and also creates an iterator to walk the | |
801 | * _ddebugs. Note that we create a seq_file always, even for O_WRONLY | |
802 | * files where it's not needed, as doing so simplifies the ->release | |
803 | * method. | |
e9d376f0 JB |
804 | */ |
805 | static int ddebug_proc_open(struct inode *inode, struct file *file) | |
806 | { | |
807 | struct ddebug_iter *iter; | |
808 | int err; | |
809 | ||
b8ccd5de | 810 | vpr_info("called\n"); |
e9d376f0 JB |
811 | |
812 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
813 | if (iter == NULL) | |
814 | return -ENOMEM; | |
815 | ||
816 | err = seq_open(file, &ddebug_proc_seqops); | |
817 | if (err) { | |
818 | kfree(iter); | |
819 | return err; | |
820 | } | |
821 | ((struct seq_file *) file->private_data)->private = iter; | |
822 | return 0; | |
823 | } | |
824 | ||
825 | static const struct file_operations ddebug_proc_fops = { | |
826 | .owner = THIS_MODULE, | |
827 | .open = ddebug_proc_open, | |
828 | .read = seq_read, | |
829 | .llseek = seq_lseek, | |
830 | .release = seq_release_private, | |
831 | .write = ddebug_proc_write | |
832 | }; | |
833 | ||
834 | /* | |
835 | * Allocate a new ddebug_table for the given module | |
836 | * and add it to the global list. | |
837 | */ | |
838 | int ddebug_add_module(struct _ddebug *tab, unsigned int n, | |
839 | const char *name) | |
840 | { | |
841 | struct ddebug_table *dt; | |
842 | char *new_name; | |
843 | ||
844 | dt = kzalloc(sizeof(*dt), GFP_KERNEL); | |
845 | if (dt == NULL) | |
846 | return -ENOMEM; | |
847 | new_name = kstrdup(name, GFP_KERNEL); | |
848 | if (new_name == NULL) { | |
849 | kfree(dt); | |
850 | return -ENOMEM; | |
851 | } | |
852 | dt->mod_name = new_name; | |
853 | dt->num_ddebugs = n; | |
e9d376f0 JB |
854 | dt->ddebugs = tab; |
855 | ||
856 | mutex_lock(&ddebug_lock); | |
857 | list_add_tail(&dt->link, &ddebug_tables); | |
858 | mutex_unlock(&ddebug_lock); | |
859 | ||
b8ccd5de | 860 | vpr_info("%u debug prints in module %s\n", n, dt->mod_name); |
e9d376f0 JB |
861 | return 0; |
862 | } | |
863 | EXPORT_SYMBOL_GPL(ddebug_add_module); | |
864 | ||
b48420c1 JC |
865 | /* handle both dyndbg=".." and $module.dyndbg=".." params at boot */ |
866 | static int ddebug_dyndbg_boot_param_cb(char *param, char *val, | |
867 | const char *unused) | |
868 | { | |
869 | const char *modname = NULL; | |
870 | char *sep; | |
871 | ||
872 | sep = strchr(param, '.'); | |
873 | if (sep) { | |
874 | *sep = '\0'; | |
875 | modname = param; | |
876 | param = sep + 1; | |
877 | } | |
878 | if (strcmp(param, "dyndbg")) | |
879 | return 0; /* skip all other params w/o error */ | |
880 | ||
881 | vpr_info("module: %s %s=\"%s\"\n", modname, param, val); | |
882 | ||
883 | ddebug_exec_queries(val ? val : "+p"); | |
884 | return 0; /* query failure shouldnt stop module load */ | |
885 | } | |
886 | ||
887 | /* handle dyndbg args to modprobe */ | |
888 | int ddebug_dyndbg_module_param_cb(char *param, char *val, const char *doing) | |
889 | { | |
890 | if (strcmp(param, "dyndbg")) | |
891 | return -ENOENT; | |
892 | ||
893 | vpr_info("module: %s %s=\"%s\"\n", doing, param, val); | |
894 | ||
895 | ddebug_exec_queries((val ? val : "+p")); | |
896 | ||
897 | return 0; /* query failure shouldnt stop module load */ | |
898 | } | |
899 | ||
e9d376f0 JB |
900 | static void ddebug_table_free(struct ddebug_table *dt) |
901 | { | |
902 | list_del_init(&dt->link); | |
903 | kfree(dt->mod_name); | |
904 | kfree(dt); | |
905 | } | |
906 | ||
907 | /* | |
908 | * Called in response to a module being unloaded. Removes | |
909 | * any ddebug_table's which point at the module. | |
910 | */ | |
ff49d74a | 911 | int ddebug_remove_module(const char *mod_name) |
e9d376f0 JB |
912 | { |
913 | struct ddebug_table *dt, *nextdt; | |
914 | int ret = -ENOENT; | |
915 | ||
b8ccd5de | 916 | vpr_info("removing module \"%s\"\n", mod_name); |
e9d376f0 JB |
917 | |
918 | mutex_lock(&ddebug_lock); | |
919 | list_for_each_entry_safe(dt, nextdt, &ddebug_tables, link) { | |
920 | if (!strcmp(dt->mod_name, mod_name)) { | |
921 | ddebug_table_free(dt); | |
922 | ret = 0; | |
923 | } | |
924 | } | |
925 | mutex_unlock(&ddebug_lock); | |
926 | return ret; | |
927 | } | |
928 | EXPORT_SYMBOL_GPL(ddebug_remove_module); | |
929 | ||
930 | static void ddebug_remove_all_tables(void) | |
931 | { | |
932 | mutex_lock(&ddebug_lock); | |
933 | while (!list_empty(&ddebug_tables)) { | |
934 | struct ddebug_table *dt = list_entry(ddebug_tables.next, | |
935 | struct ddebug_table, | |
936 | link); | |
937 | ddebug_table_free(dt); | |
938 | } | |
939 | mutex_unlock(&ddebug_lock); | |
940 | } | |
941 | ||
6a5c083d TR |
942 | static __initdata int ddebug_init_success; |
943 | ||
944 | static int __init dynamic_debug_init_debugfs(void) | |
e9d376f0 JB |
945 | { |
946 | struct dentry *dir, *file; | |
6a5c083d TR |
947 | |
948 | if (!ddebug_init_success) | |
949 | return -ENODEV; | |
e9d376f0 JB |
950 | |
951 | dir = debugfs_create_dir("dynamic_debug", NULL); | |
952 | if (!dir) | |
953 | return -ENOMEM; | |
954 | file = debugfs_create_file("control", 0644, dir, NULL, | |
955 | &ddebug_proc_fops); | |
956 | if (!file) { | |
957 | debugfs_remove(dir); | |
958 | return -ENOMEM; | |
959 | } | |
6a5c083d TR |
960 | return 0; |
961 | } | |
962 | ||
963 | static int __init dynamic_debug_init(void) | |
964 | { | |
965 | struct _ddebug *iter, *iter_start; | |
966 | const char *modname = NULL; | |
b48420c1 | 967 | char *cmdline; |
6a5c083d TR |
968 | int ret = 0; |
969 | int n = 0; | |
970 | ||
b5b78f83 JC |
971 | if (__start___verbose == __stop___verbose) { |
972 | pr_warn("_ddebug table is empty in a " | |
973 | "CONFIG_DYNAMIC_DEBUG build"); | |
974 | return 1; | |
975 | } | |
976 | iter = __start___verbose; | |
977 | modname = iter->modname; | |
978 | iter_start = iter; | |
979 | for (; iter < __stop___verbose; iter++) { | |
980 | if (strcmp(modname, iter->modname)) { | |
981 | ret = ddebug_add_module(iter_start, n, modname); | |
982 | if (ret) | |
983 | goto out_free; | |
984 | n = 0; | |
985 | modname = iter->modname; | |
986 | iter_start = iter; | |
e9d376f0 | 987 | } |
b5b78f83 | 988 | n++; |
e9d376f0 | 989 | } |
b5b78f83 JC |
990 | ret = ddebug_add_module(iter_start, n, modname); |
991 | if (ret) | |
992 | goto out_free; | |
a648ec05 TR |
993 | |
994 | /* ddebug_query boot param got passed -> set it up */ | |
995 | if (ddebug_setup_string[0] != '\0') { | |
85f7f6c0 JC |
996 | ret = ddebug_exec_queries(ddebug_setup_string); |
997 | if (ret < 0) | |
4ad275e5 JP |
998 | pr_warn("Invalid ddebug boot param %s", |
999 | ddebug_setup_string); | |
a648ec05 | 1000 | else |
85f7f6c0 JC |
1001 | pr_info("%d changes by ddebug_query\n", ret); |
1002 | ||
1003 | /* keep tables even on ddebug_query parse error */ | |
1004 | ret = 0; | |
a648ec05 | 1005 | } |
b48420c1 JC |
1006 | /* now that ddebug tables are loaded, process all boot args |
1007 | * again to find and activate queries given in dyndbg params. | |
1008 | * While this has already been done for known boot params, it | |
1009 | * ignored the unknown ones (dyndbg in particular). Reusing | |
1010 | * parse_args avoids ad-hoc parsing. This will also attempt | |
1011 | * to activate queries for not-yet-loaded modules, which is | |
1012 | * slightly noisy if verbose, but harmless. | |
1013 | */ | |
1014 | cmdline = kstrdup(saved_command_line, GFP_KERNEL); | |
1015 | parse_args("dyndbg params", cmdline, NULL, | |
1016 | 0, 0, 0, &ddebug_dyndbg_boot_param_cb); | |
1017 | kfree(cmdline); | |
a648ec05 | 1018 | |
e9d376f0 | 1019 | out_free: |
6a5c083d | 1020 | if (ret) |
e9d376f0 | 1021 | ddebug_remove_all_tables(); |
6a5c083d TR |
1022 | else |
1023 | ddebug_init_success = 1; | |
e9d376f0 JB |
1024 | return 0; |
1025 | } | |
6a5c083d TR |
1026 | /* Allow early initialization for boot messages via boot param */ |
1027 | arch_initcall(dynamic_debug_init); | |
b48420c1 | 1028 | |
6a5c083d TR |
1029 | /* Debugfs setup must be done later */ |
1030 | module_init(dynamic_debug_init_debugfs); |