Commit | Line | Data |
---|---|---|
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> | |
fef15d2f GKH |
17 | #include <linux/moduleparam.h> |
18 | #include <linux/kallsyms.h> | |
19 | #include <linux/types.h> | |
e9d376f0 | 20 | #include <linux/mutex.h> |
fef15d2f | 21 | #include <linux/proc_fs.h> |
e9d376f0 | 22 | #include <linux/seq_file.h> |
fef15d2f GKH |
23 | #include <linux/list.h> |
24 | #include <linux/sysctl.h> | |
e9d376f0 | 25 | #include <linux/ctype.h> |
fef15d2f GKH |
26 | #include <linux/string.h> |
27 | #include <linux/uaccess.h> | |
e9d376f0 JB |
28 | #include <linux/dynamic_debug.h> |
29 | #include <linux/debugfs.h> | |
5a0e3ad6 | 30 | #include <linux/slab.h> |
fef15d2f | 31 | #include <linux/jump_label.h> |
8ba6ebf5 | 32 | #include <linux/hardirq.h> |
e8d9792a | 33 | #include <linux/sched.h> |
fef15d2f | 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 | 64 | |
2b678319 JC |
65 | /* Return the path relative to source root */ |
66 | static inline const char *trim_prefix(const char *path) | |
67 | { | |
68 | int skip = strlen(__FILE__) - strlen("lib/dynamic_debug.c"); | |
69 | ||
70 | if (strncmp(path, __FILE__, skip)) | |
71 | skip = 0; /* prefix mismatch, don't skip */ | |
72 | ||
73 | return path + skip; | |
74 | } | |
75 | ||
8ba6ebf5 BVA |
76 | static struct { unsigned flag:8; char opt_char; } opt_array[] = { |
77 | { _DPRINTK_FLAGS_PRINT, 'p' }, | |
78 | { _DPRINTK_FLAGS_INCL_MODNAME, 'm' }, | |
79 | { _DPRINTK_FLAGS_INCL_FUNCNAME, 'f' }, | |
80 | { _DPRINTK_FLAGS_INCL_LINENO, 'l' }, | |
81 | { _DPRINTK_FLAGS_INCL_TID, 't' }, | |
5ca7d2a6 | 82 | { _DPRINTK_FLAGS_NONE, '_' }, |
8ba6ebf5 BVA |
83 | }; |
84 | ||
e9d376f0 JB |
85 | /* format a string into buf[] which describes the _ddebug's flags */ |
86 | static char *ddebug_describe_flags(struct _ddebug *dp, char *buf, | |
87 | size_t maxlen) | |
88 | { | |
89 | char *p = buf; | |
8ba6ebf5 | 90 | int i; |
e9d376f0 | 91 | |
5ca7d2a6 | 92 | BUG_ON(maxlen < 6); |
8ba6ebf5 BVA |
93 | for (i = 0; i < ARRAY_SIZE(opt_array); ++i) |
94 | if (dp->flags & opt_array[i].flag) | |
95 | *p++ = opt_array[i].opt_char; | |
e9d376f0 | 96 | if (p == buf) |
5ca7d2a6 | 97 | *p++ = '_'; |
e9d376f0 JB |
98 | *p = '\0'; |
99 | ||
100 | return buf; | |
101 | } | |
102 | ||
b8ccd5de JC |
103 | #define vpr_info(fmt, ...) \ |
104 | if (verbose) do { pr_info(fmt, ##__VA_ARGS__); } while (0) | |
105 | ||
106 | #define vpr_info_dq(q, msg) \ | |
107 | do { \ | |
108 | /* trim last char off format print */ \ | |
109 | vpr_info("%s: func=\"%s\" file=\"%s\" " \ | |
110 | "module=\"%s\" format=\"%.*s\" " \ | |
111 | "lineno=%u-%u", \ | |
112 | msg, \ | |
113 | q->function ? q->function : "", \ | |
114 | q->filename ? q->filename : "", \ | |
115 | q->module ? q->module : "", \ | |
116 | (int)(q->format ? strlen(q->format) - 1 : 0), \ | |
117 | q->format ? q->format : "", \ | |
118 | q->first_lineno, q->last_lineno); \ | |
574b3725 JC |
119 | } while (0) |
120 | ||
e9d376f0 | 121 | /* |
85f7f6c0 JC |
122 | * Search the tables for _ddebug's which match the given `query' and |
123 | * apply the `flags' and `mask' to them. Returns number of matching | |
124 | * callsites, normally the same as number of changes. If verbose, | |
125 | * logs the changes. Takes ddebug_lock. | |
e9d376f0 | 126 | */ |
85f7f6c0 JC |
127 | static int ddebug_change(const struct ddebug_query *query, |
128 | unsigned int flags, unsigned int mask) | |
e9d376f0 JB |
129 | { |
130 | int i; | |
131 | struct ddebug_table *dt; | |
132 | unsigned int newflags; | |
133 | unsigned int nfound = 0; | |
5ca7d2a6 | 134 | char flagbuf[10]; |
e9d376f0 JB |
135 | |
136 | /* search for matching ddebugs */ | |
137 | mutex_lock(&ddebug_lock); | |
138 | list_for_each_entry(dt, &ddebug_tables, link) { | |
139 | ||
140 | /* match against the module name */ | |
d6a238d2 | 141 | if (query->module && strcmp(query->module, dt->mod_name)) |
e9d376f0 JB |
142 | continue; |
143 | ||
144 | for (i = 0 ; i < dt->num_ddebugs ; i++) { | |
145 | struct _ddebug *dp = &dt->ddebugs[i]; | |
146 | ||
147 | /* match against the source filename */ | |
d6a238d2 | 148 | if (query->filename && |
e9d376f0 | 149 | strcmp(query->filename, dp->filename) && |
35367ab2 | 150 | strcmp(query->filename, kbasename(dp->filename)) && |
2b678319 | 151 | strcmp(query->filename, trim_prefix(dp->filename))) |
e9d376f0 JB |
152 | continue; |
153 | ||
154 | /* match against the function */ | |
d6a238d2 | 155 | if (query->function && |
e9d376f0 JB |
156 | strcmp(query->function, dp->function)) |
157 | continue; | |
158 | ||
159 | /* match against the format */ | |
d6a238d2 JC |
160 | if (query->format && |
161 | !strstr(dp->format, query->format)) | |
e9d376f0 JB |
162 | continue; |
163 | ||
164 | /* match against the line number range */ | |
165 | if (query->first_lineno && | |
166 | dp->lineno < query->first_lineno) | |
167 | continue; | |
168 | if (query->last_lineno && | |
169 | dp->lineno > query->last_lineno) | |
170 | continue; | |
171 | ||
172 | nfound++; | |
173 | ||
174 | newflags = (dp->flags & mask) | flags; | |
175 | if (newflags == dp->flags) | |
176 | continue; | |
e9d376f0 | 177 | dp->flags = newflags; |
b8ccd5de JC |
178 | vpr_info("changed %s:%d [%s]%s =%s\n", |
179 | trim_prefix(dp->filename), dp->lineno, | |
180 | dt->mod_name, dp->function, | |
181 | ddebug_describe_flags(dp, flagbuf, | |
182 | sizeof(flagbuf))); | |
e9d376f0 JB |
183 | } |
184 | } | |
185 | mutex_unlock(&ddebug_lock); | |
186 | ||
187 | if (!nfound && verbose) | |
4ad275e5 | 188 | pr_info("no matches for query\n"); |
85f7f6c0 JC |
189 | |
190 | return nfound; | |
e9d376f0 JB |
191 | } |
192 | ||
e9d376f0 JB |
193 | /* |
194 | * Split the buffer `buf' into space-separated words. | |
9898abb3 GB |
195 | * Handles simple " and ' quoting, i.e. without nested, |
196 | * embedded or escaped \". Return the number of words | |
197 | * or <0 on error. | |
e9d376f0 JB |
198 | */ |
199 | static int ddebug_tokenize(char *buf, char *words[], int maxwords) | |
200 | { | |
201 | int nwords = 0; | |
202 | ||
9898abb3 GB |
203 | while (*buf) { |
204 | char *end; | |
205 | ||
206 | /* Skip leading whitespace */ | |
e7d2860b | 207 | buf = skip_spaces(buf); |
9898abb3 GB |
208 | if (!*buf) |
209 | break; /* oh, it was trailing whitespace */ | |
8bd6026e JC |
210 | if (*buf == '#') |
211 | break; /* token starts comment, skip rest of line */ | |
9898abb3 | 212 | |
07100be7 | 213 | /* find `end' of word, whitespace separated or quoted */ |
9898abb3 GB |
214 | if (*buf == '"' || *buf == '\'') { |
215 | int quote = *buf++; | |
216 | for (end = buf ; *end && *end != quote ; end++) | |
217 | ; | |
218 | if (!*end) | |
219 | return -EINVAL; /* unclosed quote */ | |
220 | } else { | |
221 | for (end = buf ; *end && !isspace(*end) ; end++) | |
222 | ; | |
223 | BUG_ON(end == buf); | |
224 | } | |
9898abb3 | 225 | |
07100be7 | 226 | /* `buf' is start of word, `end' is one past its end */ |
9898abb3 GB |
227 | if (nwords == maxwords) |
228 | return -EINVAL; /* ran out of words[] before bytes */ | |
229 | if (*end) | |
230 | *end++ = '\0'; /* terminate the word */ | |
231 | words[nwords++] = buf; | |
232 | buf = end; | |
233 | } | |
e9d376f0 JB |
234 | |
235 | if (verbose) { | |
236 | int i; | |
4ad275e5 | 237 | pr_info("split into words:"); |
e9d376f0 | 238 | for (i = 0 ; i < nwords ; i++) |
4ad275e5 JP |
239 | pr_cont(" \"%s\"", words[i]); |
240 | pr_cont("\n"); | |
e9d376f0 JB |
241 | } |
242 | ||
243 | return nwords; | |
244 | } | |
245 | ||
246 | /* | |
247 | * Parse a single line number. Note that the empty string "" | |
248 | * is treated as a special case and converted to zero, which | |
249 | * is later treated as a "don't care" value. | |
250 | */ | |
251 | static inline int parse_lineno(const char *str, unsigned int *val) | |
252 | { | |
253 | char *end = NULL; | |
254 | BUG_ON(str == NULL); | |
255 | if (*str == '\0') { | |
256 | *val = 0; | |
257 | return 0; | |
258 | } | |
259 | *val = simple_strtoul(str, &end, 10); | |
260 | return end == NULL || end == str || *end != '\0' ? -EINVAL : 0; | |
261 | } | |
262 | ||
263 | /* | |
264 | * Undo octal escaping in a string, inplace. This is useful to | |
265 | * allow the user to express a query which matches a format | |
266 | * containing embedded spaces. | |
267 | */ | |
268 | #define isodigit(c) ((c) >= '0' && (c) <= '7') | |
269 | static char *unescape(char *str) | |
270 | { | |
271 | char *in = str; | |
272 | char *out = str; | |
273 | ||
274 | while (*in) { | |
275 | if (*in == '\\') { | |
276 | if (in[1] == '\\') { | |
277 | *out++ = '\\'; | |
278 | in += 2; | |
279 | continue; | |
280 | } else if (in[1] == 't') { | |
281 | *out++ = '\t'; | |
282 | in += 2; | |
283 | continue; | |
284 | } else if (in[1] == 'n') { | |
285 | *out++ = '\n'; | |
286 | in += 2; | |
287 | continue; | |
288 | } else if (isodigit(in[1]) && | |
289 | isodigit(in[2]) && | |
290 | isodigit(in[3])) { | |
291 | *out++ = ((in[1] - '0')<<6) | | |
292 | ((in[2] - '0')<<3) | | |
293 | (in[3] - '0'); | |
294 | in += 4; | |
295 | continue; | |
296 | } | |
297 | } | |
298 | *out++ = *in++; | |
299 | } | |
300 | *out = '\0'; | |
301 | ||
302 | return str; | |
303 | } | |
304 | ||
820874c7 JC |
305 | static int check_set(const char **dest, char *src, char *name) |
306 | { | |
307 | int rc = 0; | |
308 | ||
309 | if (*dest) { | |
310 | rc = -EINVAL; | |
311 | pr_err("match-spec:%s val:%s overridden by %s", | |
312 | name, *dest, src); | |
313 | } | |
314 | *dest = src; | |
315 | return rc; | |
316 | } | |
317 | ||
e9d376f0 JB |
318 | /* |
319 | * Parse words[] as a ddebug query specification, which is a series | |
320 | * of (keyword, value) pairs chosen from these possibilities: | |
321 | * | |
322 | * func <function-name> | |
323 | * file <full-pathname> | |
324 | * file <base-filename> | |
325 | * module <module-name> | |
326 | * format <escaped-string-to-find-in-format> | |
327 | * line <lineno> | |
328 | * line <first-lineno>-<last-lineno> // where either may be empty | |
820874c7 JC |
329 | * |
330 | * Only 1 of each type is allowed. | |
331 | * Returns 0 on success, <0 on error. | |
e9d376f0 JB |
332 | */ |
333 | static int ddebug_parse_query(char *words[], int nwords, | |
8e59b5cf | 334 | struct ddebug_query *query, const char *modname) |
e9d376f0 JB |
335 | { |
336 | unsigned int i; | |
820874c7 | 337 | int rc; |
e9d376f0 JB |
338 | |
339 | /* check we have an even number of words */ | |
340 | if (nwords % 2 != 0) | |
341 | return -EINVAL; | |
342 | memset(query, 0, sizeof(*query)); | |
343 | ||
8e59b5cf JC |
344 | if (modname) |
345 | /* support $modname.dyndbg=<multiple queries> */ | |
346 | query->module = modname; | |
347 | ||
e9d376f0 JB |
348 | for (i = 0 ; i < nwords ; i += 2) { |
349 | if (!strcmp(words[i], "func")) | |
820874c7 | 350 | rc = check_set(&query->function, words[i+1], "func"); |
e9d376f0 | 351 | else if (!strcmp(words[i], "file")) |
820874c7 | 352 | rc = check_set(&query->filename, words[i+1], "file"); |
e9d376f0 | 353 | else if (!strcmp(words[i], "module")) |
820874c7 | 354 | rc = check_set(&query->module, words[i+1], "module"); |
e9d376f0 | 355 | else if (!strcmp(words[i], "format")) |
820874c7 JC |
356 | rc = check_set(&query->format, unescape(words[i+1]), |
357 | "format"); | |
e9d376f0 JB |
358 | else if (!strcmp(words[i], "line")) { |
359 | char *first = words[i+1]; | |
360 | char *last = strchr(first, '-'); | |
820874c7 JC |
361 | if (query->first_lineno || query->last_lineno) { |
362 | pr_err("match-spec:line given 2 times\n"); | |
363 | return -EINVAL; | |
364 | } | |
e9d376f0 JB |
365 | if (last) |
366 | *last++ = '\0'; | |
367 | if (parse_lineno(first, &query->first_lineno) < 0) | |
368 | return -EINVAL; | |
820874c7 | 369 | if (last) { |
e9d376f0 | 370 | /* range <first>-<last> */ |
820874c7 JC |
371 | if (parse_lineno(last, &query->last_lineno) |
372 | < query->first_lineno) { | |
373 | pr_err("last-line < 1st-line\n"); | |
e9d376f0 | 374 | return -EINVAL; |
820874c7 | 375 | } |
e9d376f0 JB |
376 | } else { |
377 | query->last_lineno = query->first_lineno; | |
378 | } | |
379 | } else { | |
ae27f86a | 380 | pr_err("unknown keyword \"%s\"\n", words[i]); |
e9d376f0 JB |
381 | return -EINVAL; |
382 | } | |
820874c7 JC |
383 | if (rc) |
384 | return rc; | |
e9d376f0 | 385 | } |
574b3725 | 386 | vpr_info_dq(query, "parsed"); |
e9d376f0 JB |
387 | return 0; |
388 | } | |
389 | ||
390 | /* | |
391 | * Parse `str' as a flags specification, format [-+=][p]+. | |
392 | * Sets up *maskp and *flagsp to be used when changing the | |
393 | * flags fields of matched _ddebug's. Returns 0 on success | |
394 | * or <0 on error. | |
395 | */ | |
396 | static int ddebug_parse_flags(const char *str, unsigned int *flagsp, | |
397 | unsigned int *maskp) | |
398 | { | |
399 | unsigned flags = 0; | |
8ba6ebf5 | 400 | int op = '=', i; |
e9d376f0 JB |
401 | |
402 | switch (*str) { | |
403 | case '+': | |
404 | case '-': | |
405 | case '=': | |
406 | op = *str++; | |
407 | break; | |
408 | default: | |
409 | return -EINVAL; | |
410 | } | |
b8ccd5de | 411 | vpr_info("op='%c'\n", op); |
e9d376f0 JB |
412 | |
413 | for ( ; *str ; ++str) { | |
8ba6ebf5 BVA |
414 | for (i = ARRAY_SIZE(opt_array) - 1; i >= 0; i--) { |
415 | if (*str == opt_array[i].opt_char) { | |
416 | flags |= opt_array[i].flag; | |
417 | break; | |
418 | } | |
e9d376f0 | 419 | } |
8ba6ebf5 BVA |
420 | if (i < 0) |
421 | return -EINVAL; | |
e9d376f0 | 422 | } |
b8ccd5de | 423 | vpr_info("flags=0x%x\n", flags); |
e9d376f0 JB |
424 | |
425 | /* calculate final *flagsp, *maskp according to mask and op */ | |
426 | switch (op) { | |
427 | case '=': | |
428 | *maskp = 0; | |
429 | *flagsp = flags; | |
430 | break; | |
431 | case '+': | |
432 | *maskp = ~0U; | |
433 | *flagsp = flags; | |
434 | break; | |
435 | case '-': | |
436 | *maskp = ~flags; | |
437 | *flagsp = 0; | |
438 | break; | |
439 | } | |
b8ccd5de | 440 | vpr_info("*flagsp=0x%x *maskp=0x%x\n", *flagsp, *maskp); |
e9d376f0 JB |
441 | return 0; |
442 | } | |
443 | ||
8e59b5cf | 444 | static int ddebug_exec_query(char *query_string, const char *modname) |
fd89cfb8 TR |
445 | { |
446 | unsigned int flags = 0, mask = 0; | |
447 | struct ddebug_query query; | |
448 | #define MAXWORDS 9 | |
85f7f6c0 | 449 | int nwords, nfound; |
fd89cfb8 TR |
450 | char *words[MAXWORDS]; |
451 | ||
452 | nwords = ddebug_tokenize(query_string, words, MAXWORDS); | |
453 | if (nwords <= 0) | |
454 | return -EINVAL; | |
8e59b5cf | 455 | if (ddebug_parse_query(words, nwords-1, &query, modname)) |
fd89cfb8 TR |
456 | return -EINVAL; |
457 | if (ddebug_parse_flags(words[nwords-1], &flags, &mask)) | |
458 | return -EINVAL; | |
459 | ||
460 | /* actually go and implement the change */ | |
85f7f6c0 JC |
461 | nfound = ddebug_change(&query, flags, mask); |
462 | vpr_info_dq((&query), (nfound) ? "applied" : "no-match"); | |
463 | ||
464 | return nfound; | |
465 | } | |
466 | ||
467 | /* handle multiple queries in query string, continue on error, return | |
468 | last error or number of matching callsites. Module name is either | |
469 | in param (for boot arg) or perhaps in query string. | |
470 | */ | |
8e59b5cf | 471 | static int ddebug_exec_queries(char *query, const char *modname) |
85f7f6c0 JC |
472 | { |
473 | char *split; | |
474 | int i, errs = 0, exitcode = 0, rc, nfound = 0; | |
475 | ||
476 | for (i = 0; query; query = split) { | |
477 | split = strpbrk(query, ";\n"); | |
478 | if (split) | |
479 | *split++ = '\0'; | |
480 | ||
481 | query = skip_spaces(query); | |
482 | if (!query || !*query || *query == '#') | |
483 | continue; | |
484 | ||
b8ccd5de | 485 | vpr_info("query %d: \"%s\"\n", i, query); |
85f7f6c0 | 486 | |
8e59b5cf | 487 | rc = ddebug_exec_query(query, modname); |
85f7f6c0 JC |
488 | if (rc < 0) { |
489 | errs++; | |
490 | exitcode = rc; | |
491 | } else | |
492 | nfound += rc; | |
493 | i++; | |
494 | } | |
b8ccd5de | 495 | vpr_info("processed %d queries, with %d matches, %d errs\n", |
85f7f6c0 JC |
496 | i, nfound, errs); |
497 | ||
498 | if (exitcode) | |
499 | return exitcode; | |
500 | return nfound; | |
fd89cfb8 TR |
501 | } |
502 | ||
431625da JB |
503 | #define PREFIX_SIZE 64 |
504 | ||
505 | static int remaining(int wrote) | |
506 | { | |
507 | if (PREFIX_SIZE - wrote > 0) | |
508 | return PREFIX_SIZE - wrote; | |
509 | return 0; | |
510 | } | |
511 | ||
512 | static char *dynamic_emit_prefix(const struct _ddebug *desc, char *buf) | |
8ba6ebf5 | 513 | { |
431625da JB |
514 | int pos_after_tid; |
515 | int pos = 0; | |
8ba6ebf5 | 516 | |
798efc60 JP |
517 | *buf = '\0'; |
518 | ||
431625da | 519 | if (desc->flags & _DPRINTK_FLAGS_INCL_TID) { |
8ba6ebf5 | 520 | if (in_interrupt()) |
798efc60 | 521 | pos += snprintf(buf + pos, remaining(pos), "<intr> "); |
8ba6ebf5 | 522 | else |
431625da | 523 | pos += snprintf(buf + pos, remaining(pos), "[%d] ", |
798efc60 | 524 | task_pid_vnr(current)); |
8ba6ebf5 | 525 | } |
431625da JB |
526 | pos_after_tid = pos; |
527 | if (desc->flags & _DPRINTK_FLAGS_INCL_MODNAME) | |
528 | pos += snprintf(buf + pos, remaining(pos), "%s:", | |
798efc60 | 529 | desc->modname); |
431625da JB |
530 | if (desc->flags & _DPRINTK_FLAGS_INCL_FUNCNAME) |
531 | pos += snprintf(buf + pos, remaining(pos), "%s:", | |
798efc60 | 532 | desc->function); |
431625da | 533 | if (desc->flags & _DPRINTK_FLAGS_INCL_LINENO) |
07100be7 | 534 | pos += snprintf(buf + pos, remaining(pos), "%d:", |
798efc60 | 535 | desc->lineno); |
431625da JB |
536 | if (pos - pos_after_tid) |
537 | pos += snprintf(buf + pos, remaining(pos), " "); | |
538 | if (pos >= PREFIX_SIZE) | |
539 | buf[PREFIX_SIZE - 1] = '\0'; | |
6c2140ee | 540 | |
431625da | 541 | return buf; |
6c2140ee JP |
542 | } |
543 | ||
8ba6ebf5 BVA |
544 | int __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...) |
545 | { | |
546 | va_list args; | |
547 | int res; | |
431625da JB |
548 | struct va_format vaf; |
549 | char buf[PREFIX_SIZE]; | |
8ba6ebf5 BVA |
550 | |
551 | BUG_ON(!descriptor); | |
552 | BUG_ON(!fmt); | |
553 | ||
554 | va_start(args, fmt); | |
798efc60 | 555 | |
431625da JB |
556 | vaf.fmt = fmt; |
557 | vaf.va = &args; | |
798efc60 JP |
558 | |
559 | res = printk(KERN_DEBUG "%s%pV", | |
560 | dynamic_emit_prefix(descriptor, buf), &vaf); | |
561 | ||
8ba6ebf5 BVA |
562 | va_end(args); |
563 | ||
564 | return res; | |
565 | } | |
566 | EXPORT_SYMBOL(__dynamic_pr_debug); | |
567 | ||
cbc46635 JP |
568 | int __dynamic_dev_dbg(struct _ddebug *descriptor, |
569 | const struct device *dev, const char *fmt, ...) | |
570 | { | |
571 | struct va_format vaf; | |
572 | va_list args; | |
573 | int res; | |
574 | ||
575 | BUG_ON(!descriptor); | |
576 | BUG_ON(!fmt); | |
577 | ||
578 | va_start(args, fmt); | |
798efc60 | 579 | |
cbc46635 JP |
580 | vaf.fmt = fmt; |
581 | vaf.va = &args; | |
798efc60 JP |
582 | |
583 | if (!dev) { | |
584 | res = printk(KERN_DEBUG "(NULL device *): %pV", &vaf); | |
585 | } else { | |
586 | char buf[PREFIX_SIZE]; | |
798efc60 | 587 | |
666f355f JP |
588 | res = dev_printk_emit(7, dev, "%s%s %s: %pV", |
589 | dynamic_emit_prefix(descriptor, buf), | |
590 | dev_driver_string(dev), dev_name(dev), | |
591 | &vaf); | |
798efc60 JP |
592 | } |
593 | ||
cbc46635 JP |
594 | va_end(args); |
595 | ||
596 | return res; | |
597 | } | |
598 | EXPORT_SYMBOL(__dynamic_dev_dbg); | |
599 | ||
0feefd97 JB |
600 | #ifdef CONFIG_NET |
601 | ||
ffa10cb4 | 602 | int __dynamic_netdev_dbg(struct _ddebug *descriptor, |
b004ff49 | 603 | const struct net_device *dev, const char *fmt, ...) |
ffa10cb4 JB |
604 | { |
605 | struct va_format vaf; | |
606 | va_list args; | |
607 | int res; | |
608 | ||
609 | BUG_ON(!descriptor); | |
610 | BUG_ON(!fmt); | |
611 | ||
612 | va_start(args, fmt); | |
b004ff49 | 613 | |
ffa10cb4 JB |
614 | vaf.fmt = fmt; |
615 | vaf.va = &args; | |
b004ff49 JP |
616 | |
617 | if (dev && dev->dev.parent) { | |
618 | char buf[PREFIX_SIZE]; | |
666f355f JP |
619 | |
620 | res = dev_printk_emit(7, dev->dev.parent, | |
621 | "%s%s %s %s: %pV", | |
622 | dynamic_emit_prefix(descriptor, buf), | |
623 | dev_driver_string(dev->dev.parent), | |
624 | dev_name(dev->dev.parent), | |
625 | netdev_name(dev), &vaf); | |
b004ff49 JP |
626 | } else if (dev) { |
627 | res = printk(KERN_DEBUG "%s: %pV", netdev_name(dev), &vaf); | |
628 | } else { | |
629 | res = printk(KERN_DEBUG "(NULL net_device): %pV", &vaf); | |
630 | } | |
631 | ||
ffa10cb4 JB |
632 | va_end(args); |
633 | ||
634 | return res; | |
635 | } | |
636 | EXPORT_SYMBOL(__dynamic_netdev_dbg); | |
637 | ||
0feefd97 JB |
638 | #endif |
639 | ||
bc757f6f JC |
640 | #define DDEBUG_STRING_SIZE 1024 |
641 | static __initdata char ddebug_setup_string[DDEBUG_STRING_SIZE]; | |
642 | ||
a648ec05 TR |
643 | static __init int ddebug_setup_query(char *str) |
644 | { | |
bc757f6f | 645 | if (strlen(str) >= DDEBUG_STRING_SIZE) { |
4ad275e5 | 646 | pr_warn("ddebug boot param string too large\n"); |
a648ec05 TR |
647 | return 0; |
648 | } | |
bc757f6f | 649 | strlcpy(ddebug_setup_string, str, DDEBUG_STRING_SIZE); |
a648ec05 TR |
650 | return 1; |
651 | } | |
652 | ||
653 | __setup("ddebug_query=", ddebug_setup_query); | |
654 | ||
e9d376f0 JB |
655 | /* |
656 | * File_ops->write method for <debugfs>/dynamic_debug/conrol. Gathers the | |
657 | * command text from userspace, parses and executes it. | |
658 | */ | |
7281491c | 659 | #define USER_BUF_PAGE 4096 |
e9d376f0 JB |
660 | static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf, |
661 | size_t len, loff_t *offp) | |
662 | { | |
7281491c | 663 | char *tmpbuf; |
fd89cfb8 | 664 | int ret; |
e9d376f0 JB |
665 | |
666 | if (len == 0) | |
667 | return 0; | |
7281491c JC |
668 | if (len > USER_BUF_PAGE - 1) { |
669 | pr_warn("expected <%d bytes into control\n", USER_BUF_PAGE); | |
e9d376f0 | 670 | return -E2BIG; |
7281491c JC |
671 | } |
672 | tmpbuf = kmalloc(len + 1, GFP_KERNEL); | |
673 | if (!tmpbuf) | |
674 | return -ENOMEM; | |
675 | if (copy_from_user(tmpbuf, ubuf, len)) { | |
676 | kfree(tmpbuf); | |
e9d376f0 | 677 | return -EFAULT; |
7281491c | 678 | } |
e9d376f0 | 679 | tmpbuf[len] = '\0'; |
b8ccd5de | 680 | vpr_info("read %d bytes from userspace\n", (int)len); |
e9d376f0 | 681 | |
8e59b5cf | 682 | ret = ddebug_exec_queries(tmpbuf, NULL); |
7281491c | 683 | kfree(tmpbuf); |
85f7f6c0 | 684 | if (ret < 0) |
fd89cfb8 | 685 | return ret; |
e9d376f0 JB |
686 | |
687 | *offp += len; | |
688 | return len; | |
689 | } | |
690 | ||
691 | /* | |
692 | * Set the iterator to point to the first _ddebug object | |
693 | * and return a pointer to that first object. Returns | |
694 | * NULL if there are no _ddebugs at all. | |
695 | */ | |
696 | static struct _ddebug *ddebug_iter_first(struct ddebug_iter *iter) | |
697 | { | |
698 | if (list_empty(&ddebug_tables)) { | |
699 | iter->table = NULL; | |
700 | iter->idx = 0; | |
701 | return NULL; | |
702 | } | |
703 | iter->table = list_entry(ddebug_tables.next, | |
704 | struct ddebug_table, link); | |
705 | iter->idx = 0; | |
706 | return &iter->table->ddebugs[iter->idx]; | |
707 | } | |
708 | ||
709 | /* | |
710 | * Advance the iterator to point to the next _ddebug | |
711 | * object from the one the iterator currently points at, | |
712 | * and returns a pointer to the new _ddebug. Returns | |
713 | * NULL if the iterator has seen all the _ddebugs. | |
714 | */ | |
715 | static struct _ddebug *ddebug_iter_next(struct ddebug_iter *iter) | |
716 | { | |
717 | if (iter->table == NULL) | |
718 | return NULL; | |
719 | if (++iter->idx == iter->table->num_ddebugs) { | |
720 | /* iterate to next table */ | |
721 | iter->idx = 0; | |
722 | if (list_is_last(&iter->table->link, &ddebug_tables)) { | |
723 | iter->table = NULL; | |
724 | return NULL; | |
725 | } | |
726 | iter->table = list_entry(iter->table->link.next, | |
727 | struct ddebug_table, link); | |
728 | } | |
729 | return &iter->table->ddebugs[iter->idx]; | |
730 | } | |
731 | ||
732 | /* | |
733 | * Seq_ops start method. Called at the start of every | |
734 | * read() call from userspace. Takes the ddebug_lock and | |
735 | * seeks the seq_file's iterator to the given position. | |
736 | */ | |
737 | static void *ddebug_proc_start(struct seq_file *m, loff_t *pos) | |
738 | { | |
739 | struct ddebug_iter *iter = m->private; | |
740 | struct _ddebug *dp; | |
741 | int n = *pos; | |
742 | ||
b8ccd5de | 743 | vpr_info("called m=%p *pos=%lld\n", m, (unsigned long long)*pos); |
e9d376f0 JB |
744 | |
745 | mutex_lock(&ddebug_lock); | |
746 | ||
747 | if (!n) | |
748 | return SEQ_START_TOKEN; | |
749 | if (n < 0) | |
750 | return NULL; | |
751 | dp = ddebug_iter_first(iter); | |
752 | while (dp != NULL && --n > 0) | |
753 | dp = ddebug_iter_next(iter); | |
754 | return dp; | |
755 | } | |
756 | ||
757 | /* | |
758 | * Seq_ops next method. Called several times within a read() | |
759 | * call from userspace, with ddebug_lock held. Walks to the | |
760 | * next _ddebug object with a special case for the header line. | |
761 | */ | |
762 | static void *ddebug_proc_next(struct seq_file *m, void *p, loff_t *pos) | |
763 | { | |
764 | struct ddebug_iter *iter = m->private; | |
765 | struct _ddebug *dp; | |
766 | ||
b8ccd5de JC |
767 | vpr_info("called m=%p p=%p *pos=%lld\n", |
768 | m, p, (unsigned long long)*pos); | |
e9d376f0 JB |
769 | |
770 | if (p == SEQ_START_TOKEN) | |
771 | dp = ddebug_iter_first(iter); | |
772 | else | |
773 | dp = ddebug_iter_next(iter); | |
774 | ++*pos; | |
775 | return dp; | |
776 | } | |
777 | ||
778 | /* | |
779 | * Seq_ops show method. Called several times within a read() | |
780 | * call from userspace, with ddebug_lock held. Formats the | |
781 | * current _ddebug as a single human-readable line, with a | |
782 | * special case for the header line. | |
783 | */ | |
784 | static int ddebug_proc_show(struct seq_file *m, void *p) | |
785 | { | |
786 | struct ddebug_iter *iter = m->private; | |
787 | struct _ddebug *dp = p; | |
5ca7d2a6 | 788 | char flagsbuf[10]; |
e9d376f0 | 789 | |
b8ccd5de | 790 | vpr_info("called m=%p p=%p\n", m, p); |
e9d376f0 JB |
791 | |
792 | if (p == SEQ_START_TOKEN) { | |
793 | seq_puts(m, | |
794 | "# filename:lineno [module]function flags format\n"); | |
795 | return 0; | |
796 | } | |
797 | ||
5ca7d2a6 | 798 | seq_printf(m, "%s:%u [%s]%s =%s \"", |
2b678319 | 799 | trim_prefix(dp->filename), dp->lineno, |
5ca7d2a6 JC |
800 | iter->table->mod_name, dp->function, |
801 | ddebug_describe_flags(dp, flagsbuf, sizeof(flagsbuf))); | |
e9d376f0 JB |
802 | seq_escape(m, dp->format, "\t\r\n\""); |
803 | seq_puts(m, "\"\n"); | |
804 | ||
805 | return 0; | |
806 | } | |
807 | ||
808 | /* | |
809 | * Seq_ops stop method. Called at the end of each read() | |
810 | * call from userspace. Drops ddebug_lock. | |
811 | */ | |
812 | static void ddebug_proc_stop(struct seq_file *m, void *p) | |
813 | { | |
b8ccd5de | 814 | vpr_info("called m=%p p=%p\n", m, p); |
e9d376f0 JB |
815 | mutex_unlock(&ddebug_lock); |
816 | } | |
817 | ||
818 | static const struct seq_operations ddebug_proc_seqops = { | |
819 | .start = ddebug_proc_start, | |
820 | .next = ddebug_proc_next, | |
821 | .show = ddebug_proc_show, | |
822 | .stop = ddebug_proc_stop | |
823 | }; | |
824 | ||
825 | /* | |
07100be7 JC |
826 | * File_ops->open method for <debugfs>/dynamic_debug/control. Does |
827 | * the seq_file setup dance, and also creates an iterator to walk the | |
828 | * _ddebugs. Note that we create a seq_file always, even for O_WRONLY | |
829 | * files where it's not needed, as doing so simplifies the ->release | |
830 | * method. | |
e9d376f0 JB |
831 | */ |
832 | static int ddebug_proc_open(struct inode *inode, struct file *file) | |
833 | { | |
834 | struct ddebug_iter *iter; | |
835 | int err; | |
836 | ||
b8ccd5de | 837 | vpr_info("called\n"); |
e9d376f0 JB |
838 | |
839 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
840 | if (iter == NULL) | |
841 | return -ENOMEM; | |
842 | ||
843 | err = seq_open(file, &ddebug_proc_seqops); | |
844 | if (err) { | |
845 | kfree(iter); | |
846 | return err; | |
847 | } | |
848 | ((struct seq_file *) file->private_data)->private = iter; | |
849 | return 0; | |
850 | } | |
851 | ||
852 | static const struct file_operations ddebug_proc_fops = { | |
853 | .owner = THIS_MODULE, | |
854 | .open = ddebug_proc_open, | |
855 | .read = seq_read, | |
856 | .llseek = seq_lseek, | |
857 | .release = seq_release_private, | |
858 | .write = ddebug_proc_write | |
859 | }; | |
860 | ||
861 | /* | |
862 | * Allocate a new ddebug_table for the given module | |
863 | * and add it to the global list. | |
864 | */ | |
865 | int ddebug_add_module(struct _ddebug *tab, unsigned int n, | |
866 | const char *name) | |
867 | { | |
868 | struct ddebug_table *dt; | |
869 | char *new_name; | |
870 | ||
871 | dt = kzalloc(sizeof(*dt), GFP_KERNEL); | |
872 | if (dt == NULL) | |
873 | return -ENOMEM; | |
874 | new_name = kstrdup(name, GFP_KERNEL); | |
875 | if (new_name == NULL) { | |
876 | kfree(dt); | |
877 | return -ENOMEM; | |
878 | } | |
879 | dt->mod_name = new_name; | |
880 | dt->num_ddebugs = n; | |
e9d376f0 JB |
881 | dt->ddebugs = tab; |
882 | ||
883 | mutex_lock(&ddebug_lock); | |
884 | list_add_tail(&dt->link, &ddebug_tables); | |
885 | mutex_unlock(&ddebug_lock); | |
886 | ||
b8ccd5de | 887 | vpr_info("%u debug prints in module %s\n", n, dt->mod_name); |
e9d376f0 JB |
888 | return 0; |
889 | } | |
890 | EXPORT_SYMBOL_GPL(ddebug_add_module); | |
891 | ||
6ab676e9 JC |
892 | /* helper for ddebug_dyndbg_(boot|module)_param_cb */ |
893 | static int ddebug_dyndbg_param_cb(char *param, char *val, | |
894 | const char *modname, int on_err) | |
b48420c1 | 895 | { |
b48420c1 JC |
896 | char *sep; |
897 | ||
898 | sep = strchr(param, '.'); | |
899 | if (sep) { | |
6ab676e9 | 900 | /* needed only for ddebug_dyndbg_boot_param_cb */ |
b48420c1 JC |
901 | *sep = '\0'; |
902 | modname = param; | |
903 | param = sep + 1; | |
904 | } | |
905 | if (strcmp(param, "dyndbg")) | |
6ab676e9 | 906 | return on_err; /* determined by caller */ |
b48420c1 | 907 | |
8e59b5cf JC |
908 | ddebug_exec_queries((val ? val : "+p"), modname); |
909 | ||
b48420c1 JC |
910 | return 0; /* query failure shouldnt stop module load */ |
911 | } | |
912 | ||
6ab676e9 JC |
913 | /* handle both dyndbg and $module.dyndbg params at boot */ |
914 | static int ddebug_dyndbg_boot_param_cb(char *param, char *val, | |
915 | const char *unused) | |
b48420c1 | 916 | { |
6ab676e9 JC |
917 | vpr_info("%s=\"%s\"\n", param, val); |
918 | return ddebug_dyndbg_param_cb(param, val, NULL, 0); | |
919 | } | |
b48420c1 | 920 | |
6ab676e9 JC |
921 | /* |
922 | * modprobe foo finds foo.params in boot-args, strips "foo.", and | |
923 | * passes them to load_module(). This callback gets unknown params, | |
924 | * processes dyndbg params, rejects others. | |
925 | */ | |
926 | int ddebug_dyndbg_module_param_cb(char *param, char *val, const char *module) | |
927 | { | |
928 | vpr_info("module: %s %s=\"%s\"\n", module, param, val); | |
929 | return ddebug_dyndbg_param_cb(param, val, module, -ENOENT); | |
b48420c1 JC |
930 | } |
931 | ||
e9d376f0 JB |
932 | static void ddebug_table_free(struct ddebug_table *dt) |
933 | { | |
934 | list_del_init(&dt->link); | |
935 | kfree(dt->mod_name); | |
936 | kfree(dt); | |
937 | } | |
938 | ||
939 | /* | |
940 | * Called in response to a module being unloaded. Removes | |
941 | * any ddebug_table's which point at the module. | |
942 | */ | |
ff49d74a | 943 | int ddebug_remove_module(const char *mod_name) |
e9d376f0 JB |
944 | { |
945 | struct ddebug_table *dt, *nextdt; | |
946 | int ret = -ENOENT; | |
947 | ||
b8ccd5de | 948 | vpr_info("removing module \"%s\"\n", mod_name); |
e9d376f0 JB |
949 | |
950 | mutex_lock(&ddebug_lock); | |
951 | list_for_each_entry_safe(dt, nextdt, &ddebug_tables, link) { | |
952 | if (!strcmp(dt->mod_name, mod_name)) { | |
953 | ddebug_table_free(dt); | |
954 | ret = 0; | |
955 | } | |
956 | } | |
957 | mutex_unlock(&ddebug_lock); | |
958 | return ret; | |
959 | } | |
960 | EXPORT_SYMBOL_GPL(ddebug_remove_module); | |
961 | ||
962 | static void ddebug_remove_all_tables(void) | |
963 | { | |
964 | mutex_lock(&ddebug_lock); | |
965 | while (!list_empty(&ddebug_tables)) { | |
966 | struct ddebug_table *dt = list_entry(ddebug_tables.next, | |
967 | struct ddebug_table, | |
968 | link); | |
969 | ddebug_table_free(dt); | |
970 | } | |
971 | mutex_unlock(&ddebug_lock); | |
972 | } | |
973 | ||
6a5c083d TR |
974 | static __initdata int ddebug_init_success; |
975 | ||
976 | static int __init dynamic_debug_init_debugfs(void) | |
e9d376f0 JB |
977 | { |
978 | struct dentry *dir, *file; | |
6a5c083d TR |
979 | |
980 | if (!ddebug_init_success) | |
981 | return -ENODEV; | |
e9d376f0 JB |
982 | |
983 | dir = debugfs_create_dir("dynamic_debug", NULL); | |
984 | if (!dir) | |
985 | return -ENOMEM; | |
986 | file = debugfs_create_file("control", 0644, dir, NULL, | |
987 | &ddebug_proc_fops); | |
988 | if (!file) { | |
989 | debugfs_remove(dir); | |
990 | return -ENOMEM; | |
991 | } | |
6a5c083d TR |
992 | return 0; |
993 | } | |
994 | ||
995 | static int __init dynamic_debug_init(void) | |
996 | { | |
997 | struct _ddebug *iter, *iter_start; | |
998 | const char *modname = NULL; | |
b48420c1 | 999 | char *cmdline; |
6a5c083d | 1000 | int ret = 0; |
41076927 JC |
1001 | int n = 0, entries = 0, modct = 0; |
1002 | int verbose_bytes = 0; | |
6a5c083d | 1003 | |
b5b78f83 JC |
1004 | if (__start___verbose == __stop___verbose) { |
1005 | pr_warn("_ddebug table is empty in a " | |
1006 | "CONFIG_DYNAMIC_DEBUG build"); | |
1007 | return 1; | |
1008 | } | |
1009 | iter = __start___verbose; | |
1010 | modname = iter->modname; | |
1011 | iter_start = iter; | |
1012 | for (; iter < __stop___verbose; iter++) { | |
41076927 JC |
1013 | entries++; |
1014 | verbose_bytes += strlen(iter->modname) + strlen(iter->function) | |
1015 | + strlen(iter->filename) + strlen(iter->format); | |
1016 | ||
b5b78f83 | 1017 | if (strcmp(modname, iter->modname)) { |
41076927 | 1018 | modct++; |
b5b78f83 JC |
1019 | ret = ddebug_add_module(iter_start, n, modname); |
1020 | if (ret) | |
af442399 | 1021 | goto out_err; |
b5b78f83 JC |
1022 | n = 0; |
1023 | modname = iter->modname; | |
1024 | iter_start = iter; | |
e9d376f0 | 1025 | } |
b5b78f83 | 1026 | n++; |
e9d376f0 | 1027 | } |
b5b78f83 JC |
1028 | ret = ddebug_add_module(iter_start, n, modname); |
1029 | if (ret) | |
af442399 | 1030 | goto out_err; |
a648ec05 | 1031 | |
af442399 | 1032 | ddebug_init_success = 1; |
41076927 JC |
1033 | vpr_info("%d modules, %d entries and %d bytes in ddebug tables," |
1034 | " %d bytes in (readonly) verbose section\n", | |
1035 | modct, entries, (int)( modct * sizeof(struct ddebug_table)), | |
1036 | verbose_bytes + (int)(__stop___verbose - __start___verbose)); | |
af442399 JC |
1037 | |
1038 | /* apply ddebug_query boot param, dont unload tables on err */ | |
a648ec05 | 1039 | if (ddebug_setup_string[0] != '\0') { |
f0b919d9 JC |
1040 | pr_warn("ddebug_query param name is deprecated," |
1041 | " change it to dyndbg\n"); | |
8e59b5cf | 1042 | ret = ddebug_exec_queries(ddebug_setup_string, NULL); |
85f7f6c0 | 1043 | if (ret < 0) |
4ad275e5 JP |
1044 | pr_warn("Invalid ddebug boot param %s", |
1045 | ddebug_setup_string); | |
a648ec05 | 1046 | else |
85f7f6c0 | 1047 | pr_info("%d changes by ddebug_query\n", ret); |
a648ec05 | 1048 | } |
b48420c1 JC |
1049 | /* now that ddebug tables are loaded, process all boot args |
1050 | * again to find and activate queries given in dyndbg params. | |
1051 | * While this has already been done for known boot params, it | |
1052 | * ignored the unknown ones (dyndbg in particular). Reusing | |
1053 | * parse_args avoids ad-hoc parsing. This will also attempt | |
1054 | * to activate queries for not-yet-loaded modules, which is | |
1055 | * slightly noisy if verbose, but harmless. | |
1056 | */ | |
1057 | cmdline = kstrdup(saved_command_line, GFP_KERNEL); | |
1058 | parse_args("dyndbg params", cmdline, NULL, | |
1059 | 0, 0, 0, &ddebug_dyndbg_boot_param_cb); | |
1060 | kfree(cmdline); | |
af442399 | 1061 | return 0; |
a648ec05 | 1062 | |
af442399 JC |
1063 | out_err: |
1064 | ddebug_remove_all_tables(); | |
e9d376f0 JB |
1065 | return 0; |
1066 | } | |
6a5c083d | 1067 | /* Allow early initialization for boot messages via boot param */ |
3ec5652a | 1068 | early_initcall(dynamic_debug_init); |
b48420c1 | 1069 | |
6a5c083d | 1070 | /* Debugfs setup must be done later */ |
3ec5652a | 1071 | fs_initcall(dynamic_debug_init_debugfs); |