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7ce7e424 TZ |
1 | /* |
2 | * trace_events_filter - generic event filtering | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License as published by | |
6 | * the Free Software Foundation; either version 2 of the License, or | |
7 | * (at your option) any later version. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License | |
15 | * along with this program; if not, write to the Free Software | |
16 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
17 | * | |
18 | * Copyright (C) 2009 Tom Zanussi <tzanussi@gmail.com> | |
19 | */ | |
20 | ||
7ce7e424 TZ |
21 | #include <linux/module.h> |
22 | #include <linux/ctype.h> | |
ac1adc55 | 23 | #include <linux/mutex.h> |
7ce7e424 TZ |
24 | |
25 | #include "trace.h" | |
4bda2d51 | 26 | #include "trace_output.h" |
7ce7e424 | 27 | |
8b372562 | 28 | enum filter_op_ids |
7ce7e424 | 29 | { |
8b372562 TZ |
30 | OP_OR, |
31 | OP_AND, | |
32 | OP_NE, | |
33 | OP_EQ, | |
34 | OP_LT, | |
35 | OP_LE, | |
36 | OP_GT, | |
37 | OP_GE, | |
38 | OP_NONE, | |
39 | OP_OPEN_PAREN, | |
40 | }; | |
41 | ||
42 | struct filter_op { | |
43 | int id; | |
44 | char *string; | |
45 | int precedence; | |
46 | }; | |
47 | ||
48 | static struct filter_op filter_ops[] = { | |
49 | { OP_OR, "||", 1 }, | |
50 | { OP_AND, "&&", 2 }, | |
51 | { OP_NE, "!=", 4 }, | |
52 | { OP_EQ, "==", 4 }, | |
53 | { OP_LT, "<", 5 }, | |
54 | { OP_LE, "<=", 5 }, | |
55 | { OP_GT, ">", 5 }, | |
56 | { OP_GE, ">=", 5 }, | |
57 | { OP_NONE, "OP_NONE", 0 }, | |
58 | { OP_OPEN_PAREN, "(", 0 }, | |
59 | }; | |
60 | ||
61 | enum { | |
62 | FILT_ERR_NONE, | |
63 | FILT_ERR_INVALID_OP, | |
64 | FILT_ERR_UNBALANCED_PAREN, | |
65 | FILT_ERR_TOO_MANY_OPERANDS, | |
66 | FILT_ERR_OPERAND_TOO_LONG, | |
67 | FILT_ERR_FIELD_NOT_FOUND, | |
68 | FILT_ERR_ILLEGAL_FIELD_OP, | |
69 | FILT_ERR_ILLEGAL_INTVAL, | |
70 | FILT_ERR_BAD_SUBSYS_FILTER, | |
71 | FILT_ERR_TOO_MANY_PREDS, | |
72 | FILT_ERR_MISSING_FIELD, | |
73 | FILT_ERR_INVALID_FILTER, | |
74 | }; | |
75 | ||
76 | static char *err_text[] = { | |
77 | "No error", | |
78 | "Invalid operator", | |
79 | "Unbalanced parens", | |
80 | "Too many operands", | |
81 | "Operand too long", | |
82 | "Field not found", | |
83 | "Illegal operation for field type", | |
84 | "Illegal integer value", | |
85 | "Couldn't find or set field in one of a subsystem's events", | |
86 | "Too many terms in predicate expression", | |
87 | "Missing field name and/or value", | |
88 | "Meaningless filter expression", | |
89 | }; | |
90 | ||
91 | struct opstack_op { | |
92 | int op; | |
93 | struct list_head list; | |
94 | }; | |
95 | ||
96 | struct postfix_elt { | |
97 | int op; | |
98 | char *operand; | |
99 | struct list_head list; | |
100 | }; | |
101 | ||
102 | struct filter_parse_state { | |
103 | struct filter_op *ops; | |
104 | struct list_head opstack; | |
105 | struct list_head postfix; | |
106 | int lasterr; | |
107 | int lasterr_pos; | |
108 | ||
109 | struct { | |
110 | char *string; | |
111 | unsigned int cnt; | |
112 | unsigned int tail; | |
113 | } infix; | |
114 | ||
115 | struct { | |
116 | char string[MAX_FILTER_STR_VAL]; | |
117 | int pos; | |
118 | unsigned int tail; | |
119 | } operand; | |
120 | }; | |
121 | ||
197e2eab LZ |
122 | #define DEFINE_COMPARISON_PRED(type) \ |
123 | static int filter_pred_##type(struct filter_pred *pred, void *event, \ | |
124 | int val1, int val2) \ | |
125 | { \ | |
126 | type *addr = (type *)(event + pred->offset); \ | |
127 | type val = (type)pred->val; \ | |
128 | int match = 0; \ | |
129 | \ | |
130 | switch (pred->op) { \ | |
131 | case OP_LT: \ | |
132 | match = (*addr < val); \ | |
133 | break; \ | |
134 | case OP_LE: \ | |
135 | match = (*addr <= val); \ | |
136 | break; \ | |
137 | case OP_GT: \ | |
138 | match = (*addr > val); \ | |
139 | break; \ | |
140 | case OP_GE: \ | |
141 | match = (*addr >= val); \ | |
142 | break; \ | |
143 | default: \ | |
144 | break; \ | |
145 | } \ | |
146 | \ | |
147 | return match; \ | |
148 | } | |
149 | ||
150 | #define DEFINE_EQUALITY_PRED(size) \ | |
151 | static int filter_pred_##size(struct filter_pred *pred, void *event, \ | |
152 | int val1, int val2) \ | |
153 | { \ | |
154 | u##size *addr = (u##size *)(event + pred->offset); \ | |
155 | u##size val = (u##size)pred->val; \ | |
156 | int match; \ | |
157 | \ | |
158 | match = (val == *addr) ^ pred->not; \ | |
159 | \ | |
160 | return match; \ | |
161 | } | |
162 | ||
8b372562 TZ |
163 | DEFINE_COMPARISON_PRED(s64); |
164 | DEFINE_COMPARISON_PRED(u64); | |
165 | DEFINE_COMPARISON_PRED(s32); | |
166 | DEFINE_COMPARISON_PRED(u32); | |
167 | DEFINE_COMPARISON_PRED(s16); | |
168 | DEFINE_COMPARISON_PRED(u16); | |
169 | DEFINE_COMPARISON_PRED(s8); | |
170 | DEFINE_COMPARISON_PRED(u8); | |
171 | ||
172 | DEFINE_EQUALITY_PRED(64); | |
173 | DEFINE_EQUALITY_PRED(32); | |
174 | DEFINE_EQUALITY_PRED(16); | |
175 | DEFINE_EQUALITY_PRED(8); | |
176 | ||
177 | static int filter_pred_and(struct filter_pred *pred __attribute((unused)), | |
178 | void *event __attribute((unused)), | |
179 | int val1, int val2) | |
7ce7e424 | 180 | { |
8b372562 | 181 | return val1 && val2; |
7ce7e424 TZ |
182 | } |
183 | ||
8b372562 TZ |
184 | static int filter_pred_or(struct filter_pred *pred __attribute((unused)), |
185 | void *event __attribute((unused)), | |
186 | int val1, int val2) | |
7ce7e424 | 187 | { |
8b372562 | 188 | return val1 || val2; |
7ce7e424 TZ |
189 | } |
190 | ||
e8808c10 | 191 | /* Filter predicate for fixed sized arrays of characters */ |
8b372562 TZ |
192 | static int filter_pred_string(struct filter_pred *pred, void *event, |
193 | int val1, int val2) | |
7ce7e424 TZ |
194 | { |
195 | char *addr = (char *)(event + pred->offset); | |
196 | int cmp, match; | |
197 | ||
1889d209 | 198 | cmp = pred->regex.match(addr, &pred->regex, pred->regex.field_len); |
7ce7e424 | 199 | |
1889d209 | 200 | match = cmp ^ pred->not; |
7ce7e424 TZ |
201 | |
202 | return match; | |
203 | } | |
204 | ||
87a342f5 LZ |
205 | /* Filter predicate for char * pointers */ |
206 | static int filter_pred_pchar(struct filter_pred *pred, void *event, | |
207 | int val1, int val2) | |
208 | { | |
209 | char **addr = (char **)(event + pred->offset); | |
210 | int cmp, match; | |
211 | ||
1889d209 | 212 | cmp = pred->regex.match(*addr, &pred->regex, pred->regex.field_len); |
87a342f5 | 213 | |
1889d209 | 214 | match = cmp ^ pred->not; |
87a342f5 LZ |
215 | |
216 | return match; | |
217 | } | |
218 | ||
e8808c10 FW |
219 | /* |
220 | * Filter predicate for dynamic sized arrays of characters. | |
221 | * These are implemented through a list of strings at the end | |
222 | * of the entry. | |
223 | * Also each of these strings have a field in the entry which | |
224 | * contains its offset from the beginning of the entry. | |
225 | * We have then first to get this field, dereference it | |
226 | * and add it to the address of the entry, and at last we have | |
227 | * the address of the string. | |
228 | */ | |
229 | static int filter_pred_strloc(struct filter_pred *pred, void *event, | |
230 | int val1, int val2) | |
231 | { | |
7d536cb3 LZ |
232 | u32 str_item = *(u32 *)(event + pred->offset); |
233 | int str_loc = str_item & 0xffff; | |
234 | int str_len = str_item >> 16; | |
e8808c10 FW |
235 | char *addr = (char *)(event + str_loc); |
236 | int cmp, match; | |
237 | ||
1889d209 | 238 | cmp = pred->regex.match(addr, &pred->regex, str_len); |
e8808c10 | 239 | |
1889d209 | 240 | match = cmp ^ pred->not; |
e8808c10 FW |
241 | |
242 | return match; | |
243 | } | |
244 | ||
8b372562 TZ |
245 | static int filter_pred_none(struct filter_pred *pred, void *event, |
246 | int val1, int val2) | |
0a19e53c TZ |
247 | { |
248 | return 0; | |
249 | } | |
250 | ||
1889d209 FW |
251 | /* Basic regex callbacks */ |
252 | static int regex_match_full(char *str, struct regex *r, int len) | |
253 | { | |
254 | if (strncmp(str, r->pattern, len) == 0) | |
255 | return 1; | |
256 | return 0; | |
257 | } | |
258 | ||
259 | static int regex_match_front(char *str, struct regex *r, int len) | |
260 | { | |
261 | if (strncmp(str, r->pattern, len) == 0) | |
262 | return 1; | |
263 | return 0; | |
264 | } | |
265 | ||
266 | static int regex_match_middle(char *str, struct regex *r, int len) | |
267 | { | |
268 | if (strstr(str, r->pattern)) | |
269 | return 1; | |
270 | return 0; | |
271 | } | |
272 | ||
273 | static int regex_match_end(char *str, struct regex *r, int len) | |
274 | { | |
275 | char *ptr = strstr(str, r->pattern); | |
276 | ||
277 | if (ptr && (ptr[r->len] == 0)) | |
278 | return 1; | |
279 | return 0; | |
280 | } | |
281 | ||
3f6fe06d FW |
282 | /** |
283 | * filter_parse_regex - parse a basic regex | |
284 | * @buff: the raw regex | |
285 | * @len: length of the regex | |
286 | * @search: will point to the beginning of the string to compare | |
287 | * @not: tell whether the match will have to be inverted | |
288 | * | |
289 | * This passes in a buffer containing a regex and this function will | |
1889d209 FW |
290 | * set search to point to the search part of the buffer and |
291 | * return the type of search it is (see enum above). | |
292 | * This does modify buff. | |
293 | * | |
294 | * Returns enum type. | |
295 | * search returns the pointer to use for comparison. | |
296 | * not returns 1 if buff started with a '!' | |
297 | * 0 otherwise. | |
298 | */ | |
3f6fe06d | 299 | enum regex_type filter_parse_regex(char *buff, int len, char **search, int *not) |
1889d209 FW |
300 | { |
301 | int type = MATCH_FULL; | |
302 | int i; | |
303 | ||
304 | if (buff[0] == '!') { | |
305 | *not = 1; | |
306 | buff++; | |
307 | len--; | |
308 | } else | |
309 | *not = 0; | |
310 | ||
311 | *search = buff; | |
312 | ||
313 | for (i = 0; i < len; i++) { | |
314 | if (buff[i] == '*') { | |
315 | if (!i) { | |
316 | *search = buff + 1; | |
317 | type = MATCH_END_ONLY; | |
318 | } else { | |
319 | if (type == MATCH_END_ONLY) | |
320 | type = MATCH_MIDDLE_ONLY; | |
321 | else | |
322 | type = MATCH_FRONT_ONLY; | |
323 | buff[i] = 0; | |
324 | break; | |
325 | } | |
326 | } | |
327 | } | |
328 | ||
329 | return type; | |
330 | } | |
331 | ||
332 | static int filter_build_regex(struct filter_pred *pred) | |
333 | { | |
334 | struct regex *r = &pred->regex; | |
335 | char *search, *dup; | |
336 | enum regex_type type; | |
337 | int not; | |
338 | ||
339 | type = filter_parse_regex(r->pattern, r->len, &search, ¬); | |
340 | dup = kstrdup(search, GFP_KERNEL); | |
341 | if (!dup) | |
342 | return -ENOMEM; | |
343 | ||
344 | strcpy(r->pattern, dup); | |
345 | kfree(dup); | |
346 | ||
347 | r->len = strlen(r->pattern); | |
348 | ||
349 | switch (type) { | |
350 | case MATCH_FULL: | |
351 | r->match = regex_match_full; | |
352 | break; | |
353 | case MATCH_FRONT_ONLY: | |
354 | r->match = regex_match_front; | |
355 | break; | |
356 | case MATCH_MIDDLE_ONLY: | |
357 | r->match = regex_match_middle; | |
358 | break; | |
359 | case MATCH_END_ONLY: | |
360 | r->match = regex_match_end; | |
361 | break; | |
362 | } | |
363 | ||
364 | pred->not ^= not; | |
365 | ||
366 | return 0; | |
367 | } | |
368 | ||
7ce7e424 TZ |
369 | /* return 1 if event matches, 0 otherwise (discard) */ |
370 | int filter_match_preds(struct ftrace_event_call *call, void *rec) | |
371 | { | |
30e673b2 | 372 | struct event_filter *filter = call->filter; |
8b372562 TZ |
373 | int match, top = 0, val1 = 0, val2 = 0; |
374 | int stack[MAX_FILTER_PRED]; | |
7ce7e424 | 375 | struct filter_pred *pred; |
8b372562 | 376 | int i; |
7ce7e424 | 377 | |
30e673b2 TZ |
378 | for (i = 0; i < filter->n_preds; i++) { |
379 | pred = filter->preds[i]; | |
8b372562 TZ |
380 | if (!pred->pop_n) { |
381 | match = pred->fn(pred, rec, val1, val2); | |
382 | stack[top++] = match; | |
0a19e53c | 383 | continue; |
8b372562 TZ |
384 | } |
385 | if (pred->pop_n > top) { | |
386 | WARN_ON_ONCE(1); | |
387 | return 0; | |
388 | } | |
389 | val1 = stack[--top]; | |
390 | val2 = stack[--top]; | |
391 | match = pred->fn(pred, rec, val1, val2); | |
392 | stack[top++] = match; | |
7ce7e424 TZ |
393 | } |
394 | ||
8b372562 | 395 | return stack[--top]; |
7ce7e424 | 396 | } |
17c873ec | 397 | EXPORT_SYMBOL_GPL(filter_match_preds); |
7ce7e424 | 398 | |
8b372562 | 399 | static void parse_error(struct filter_parse_state *ps, int err, int pos) |
7ce7e424 | 400 | { |
8b372562 TZ |
401 | ps->lasterr = err; |
402 | ps->lasterr_pos = pos; | |
403 | } | |
7ce7e424 | 404 | |
8b372562 TZ |
405 | static void remove_filter_string(struct event_filter *filter) |
406 | { | |
407 | kfree(filter->filter_string); | |
408 | filter->filter_string = NULL; | |
409 | } | |
410 | ||
411 | static int replace_filter_string(struct event_filter *filter, | |
412 | char *filter_string) | |
413 | { | |
414 | kfree(filter->filter_string); | |
415 | filter->filter_string = kstrdup(filter_string, GFP_KERNEL); | |
416 | if (!filter->filter_string) | |
417 | return -ENOMEM; | |
418 | ||
419 | return 0; | |
420 | } | |
421 | ||
422 | static int append_filter_string(struct event_filter *filter, | |
423 | char *string) | |
424 | { | |
425 | int newlen; | |
426 | char *new_filter_string; | |
427 | ||
428 | BUG_ON(!filter->filter_string); | |
429 | newlen = strlen(filter->filter_string) + strlen(string) + 1; | |
430 | new_filter_string = kmalloc(newlen, GFP_KERNEL); | |
431 | if (!new_filter_string) | |
432 | return -ENOMEM; | |
433 | ||
434 | strcpy(new_filter_string, filter->filter_string); | |
435 | strcat(new_filter_string, string); | |
436 | kfree(filter->filter_string); | |
437 | filter->filter_string = new_filter_string; | |
438 | ||
439 | return 0; | |
440 | } | |
441 | ||
442 | static void append_filter_err(struct filter_parse_state *ps, | |
443 | struct event_filter *filter) | |
444 | { | |
445 | int pos = ps->lasterr_pos; | |
446 | char *buf, *pbuf; | |
447 | ||
448 | buf = (char *)__get_free_page(GFP_TEMPORARY); | |
449 | if (!buf) | |
4bda2d51 | 450 | return; |
7ce7e424 | 451 | |
8b372562 TZ |
452 | append_filter_string(filter, "\n"); |
453 | memset(buf, ' ', PAGE_SIZE); | |
454 | if (pos > PAGE_SIZE - 128) | |
455 | pos = 0; | |
456 | buf[pos] = '^'; | |
457 | pbuf = &buf[pos] + 1; | |
458 | ||
459 | sprintf(pbuf, "\nparse_error: %s\n", err_text[ps->lasterr]); | |
460 | append_filter_string(filter, buf); | |
461 | free_page((unsigned long) buf); | |
7ce7e424 TZ |
462 | } |
463 | ||
8b372562 | 464 | void print_event_filter(struct ftrace_event_call *call, struct trace_seq *s) |
ac1adc55 | 465 | { |
8b372562 TZ |
466 | struct event_filter *filter = call->filter; |
467 | ||
00e95830 | 468 | mutex_lock(&event_mutex); |
8e254c1d | 469 | if (filter && filter->filter_string) |
8b372562 TZ |
470 | trace_seq_printf(s, "%s\n", filter->filter_string); |
471 | else | |
472 | trace_seq_printf(s, "none\n"); | |
00e95830 | 473 | mutex_unlock(&event_mutex); |
ac1adc55 TZ |
474 | } |
475 | ||
8b372562 | 476 | void print_subsystem_event_filter(struct event_subsystem *system, |
ac1adc55 TZ |
477 | struct trace_seq *s) |
478 | { | |
8b372562 TZ |
479 | struct event_filter *filter = system->filter; |
480 | ||
00e95830 | 481 | mutex_lock(&event_mutex); |
8e254c1d | 482 | if (filter && filter->filter_string) |
8b372562 TZ |
483 | trace_seq_printf(s, "%s\n", filter->filter_string); |
484 | else | |
485 | trace_seq_printf(s, "none\n"); | |
00e95830 | 486 | mutex_unlock(&event_mutex); |
ac1adc55 TZ |
487 | } |
488 | ||
7ce7e424 TZ |
489 | static struct ftrace_event_field * |
490 | find_event_field(struct ftrace_event_call *call, char *name) | |
491 | { | |
1fc2d5c1 | 492 | struct ftrace_event_field *field; |
7ce7e424 | 493 | |
1fc2d5c1 | 494 | list_for_each_entry(field, &call->fields, link) { |
7ce7e424 TZ |
495 | if (!strcmp(field->name, name)) |
496 | return field; | |
497 | } | |
498 | ||
499 | return NULL; | |
500 | } | |
501 | ||
8b372562 | 502 | static void filter_free_pred(struct filter_pred *pred) |
7ce7e424 TZ |
503 | { |
504 | if (!pred) | |
505 | return; | |
506 | ||
507 | kfree(pred->field_name); | |
7ce7e424 TZ |
508 | kfree(pred); |
509 | } | |
510 | ||
0a19e53c TZ |
511 | static void filter_clear_pred(struct filter_pred *pred) |
512 | { | |
513 | kfree(pred->field_name); | |
514 | pred->field_name = NULL; | |
1889d209 | 515 | pred->regex.len = 0; |
0a19e53c TZ |
516 | } |
517 | ||
518 | static int filter_set_pred(struct filter_pred *dest, | |
519 | struct filter_pred *src, | |
520 | filter_pred_fn_t fn) | |
521 | { | |
522 | *dest = *src; | |
8b372562 TZ |
523 | if (src->field_name) { |
524 | dest->field_name = kstrdup(src->field_name, GFP_KERNEL); | |
525 | if (!dest->field_name) | |
526 | return -ENOMEM; | |
527 | } | |
0a19e53c TZ |
528 | dest->fn = fn; |
529 | ||
530 | return 0; | |
531 | } | |
532 | ||
8b372562 | 533 | static void filter_disable_preds(struct ftrace_event_call *call) |
7ce7e424 | 534 | { |
30e673b2 | 535 | struct event_filter *filter = call->filter; |
7ce7e424 TZ |
536 | int i; |
537 | ||
30e673b2 TZ |
538 | call->filter_active = 0; |
539 | filter->n_preds = 0; | |
0a19e53c TZ |
540 | |
541 | for (i = 0; i < MAX_FILTER_PRED; i++) | |
30e673b2 | 542 | filter->preds[i]->fn = filter_pred_none; |
0a19e53c TZ |
543 | } |
544 | ||
2df75e41 LZ |
545 | void destroy_preds(struct ftrace_event_call *call) |
546 | { | |
547 | struct event_filter *filter = call->filter; | |
548 | int i; | |
549 | ||
8e254c1d LZ |
550 | if (!filter) |
551 | return; | |
552 | ||
2df75e41 LZ |
553 | for (i = 0; i < MAX_FILTER_PRED; i++) { |
554 | if (filter->preds[i]) | |
555 | filter_free_pred(filter->preds[i]); | |
556 | } | |
557 | kfree(filter->preds); | |
57be8887 | 558 | kfree(filter->filter_string); |
2df75e41 LZ |
559 | kfree(filter); |
560 | call->filter = NULL; | |
561 | } | |
562 | ||
8e254c1d | 563 | static int init_preds(struct ftrace_event_call *call) |
0a19e53c | 564 | { |
30e673b2 | 565 | struct event_filter *filter; |
0a19e53c TZ |
566 | struct filter_pred *pred; |
567 | int i; | |
568 | ||
c58b4321 LZ |
569 | if (call->filter) |
570 | return 0; | |
571 | ||
30e673b2 TZ |
572 | filter = call->filter = kzalloc(sizeof(*filter), GFP_KERNEL); |
573 | if (!call->filter) | |
0a19e53c TZ |
574 | return -ENOMEM; |
575 | ||
30e673b2 TZ |
576 | filter->n_preds = 0; |
577 | ||
578 | filter->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred), GFP_KERNEL); | |
579 | if (!filter->preds) | |
580 | goto oom; | |
581 | ||
0a19e53c TZ |
582 | for (i = 0; i < MAX_FILTER_PRED; i++) { |
583 | pred = kzalloc(sizeof(*pred), GFP_KERNEL); | |
584 | if (!pred) | |
585 | goto oom; | |
586 | pred->fn = filter_pred_none; | |
30e673b2 | 587 | filter->preds[i] = pred; |
0a19e53c TZ |
588 | } |
589 | ||
590 | return 0; | |
591 | ||
592 | oom: | |
2df75e41 | 593 | destroy_preds(call); |
0a19e53c TZ |
594 | |
595 | return -ENOMEM; | |
7ce7e424 | 596 | } |
8e254c1d LZ |
597 | |
598 | static int init_subsystem_preds(struct event_subsystem *system) | |
599 | { | |
600 | struct ftrace_event_call *call; | |
601 | int err; | |
602 | ||
603 | list_for_each_entry(call, &ftrace_events, list) { | |
604 | if (!call->define_fields) | |
605 | continue; | |
606 | ||
607 | if (strcmp(call->system, system->name) != 0) | |
608 | continue; | |
609 | ||
c58b4321 LZ |
610 | err = init_preds(call); |
611 | if (err) | |
612 | return err; | |
8e254c1d LZ |
613 | } |
614 | ||
615 | return 0; | |
616 | } | |
7ce7e424 | 617 | |
1f9963cb LZ |
618 | enum { |
619 | FILTER_DISABLE_ALL, | |
620 | FILTER_INIT_NO_RESET, | |
621 | FILTER_SKIP_NO_RESET, | |
622 | }; | |
623 | ||
624 | static void filter_free_subsystem_preds(struct event_subsystem *system, | |
625 | int flag) | |
cfb180f3 | 626 | { |
a59fd602 | 627 | struct ftrace_event_call *call; |
cfb180f3 | 628 | |
a59fd602 | 629 | list_for_each_entry(call, &ftrace_events, list) { |
e1112b4d | 630 | if (!call->define_fields) |
cfb180f3 TZ |
631 | continue; |
632 | ||
8e254c1d LZ |
633 | if (strcmp(call->system, system->name) != 0) |
634 | continue; | |
635 | ||
1f9963cb LZ |
636 | if (flag == FILTER_INIT_NO_RESET) { |
637 | call->filter->no_reset = false; | |
638 | continue; | |
639 | } | |
640 | ||
641 | if (flag == FILTER_SKIP_NO_RESET && call->filter->no_reset) | |
642 | continue; | |
643 | ||
8e254c1d LZ |
644 | filter_disable_preds(call); |
645 | remove_filter_string(call->filter); | |
cfb180f3 TZ |
646 | } |
647 | } | |
648 | ||
8b372562 TZ |
649 | static int filter_add_pred_fn(struct filter_parse_state *ps, |
650 | struct ftrace_event_call *call, | |
ac1adc55 TZ |
651 | struct filter_pred *pred, |
652 | filter_pred_fn_t fn) | |
7ce7e424 | 653 | { |
30e673b2 | 654 | struct event_filter *filter = call->filter; |
0a19e53c | 655 | int idx, err; |
7ce7e424 | 656 | |
8b372562 TZ |
657 | if (filter->n_preds == MAX_FILTER_PRED) { |
658 | parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0); | |
0a19e53c | 659 | return -ENOSPC; |
8b372562 | 660 | } |
7ce7e424 | 661 | |
30e673b2 TZ |
662 | idx = filter->n_preds; |
663 | filter_clear_pred(filter->preds[idx]); | |
664 | err = filter_set_pred(filter->preds[idx], pred, fn); | |
0a19e53c TZ |
665 | if (err) |
666 | return err; | |
667 | ||
30e673b2 TZ |
668 | filter->n_preds++; |
669 | call->filter_active = 1; | |
7ce7e424 | 670 | |
0a19e53c | 671 | return 0; |
7ce7e424 TZ |
672 | } |
673 | ||
aa38e9fc | 674 | int filter_assign_type(const char *type) |
7ce7e424 | 675 | { |
7fcb7c47 LZ |
676 | if (strstr(type, "__data_loc") && strstr(type, "char")) |
677 | return FILTER_DYN_STRING; | |
678 | ||
7ce7e424 | 679 | if (strchr(type, '[') && strstr(type, "char")) |
e8808c10 FW |
680 | return FILTER_STATIC_STRING; |
681 | ||
aa38e9fc LZ |
682 | return FILTER_OTHER; |
683 | } | |
684 | ||
685 | static bool is_string_field(struct ftrace_event_field *field) | |
686 | { | |
687 | return field->filter_type == FILTER_DYN_STRING || | |
87a342f5 LZ |
688 | field->filter_type == FILTER_STATIC_STRING || |
689 | field->filter_type == FILTER_PTR_STRING; | |
7ce7e424 TZ |
690 | } |
691 | ||
8b372562 TZ |
692 | static int is_legal_op(struct ftrace_event_field *field, int op) |
693 | { | |
aa38e9fc | 694 | if (is_string_field(field) && (op != OP_EQ && op != OP_NE)) |
8b372562 TZ |
695 | return 0; |
696 | ||
697 | return 1; | |
698 | } | |
699 | ||
700 | static filter_pred_fn_t select_comparison_fn(int op, int field_size, | |
701 | int field_is_signed) | |
702 | { | |
703 | filter_pred_fn_t fn = NULL; | |
704 | ||
705 | switch (field_size) { | |
706 | case 8: | |
707 | if (op == OP_EQ || op == OP_NE) | |
708 | fn = filter_pred_64; | |
709 | else if (field_is_signed) | |
710 | fn = filter_pred_s64; | |
711 | else | |
712 | fn = filter_pred_u64; | |
713 | break; | |
714 | case 4: | |
715 | if (op == OP_EQ || op == OP_NE) | |
716 | fn = filter_pred_32; | |
717 | else if (field_is_signed) | |
718 | fn = filter_pred_s32; | |
719 | else | |
720 | fn = filter_pred_u32; | |
721 | break; | |
722 | case 2: | |
723 | if (op == OP_EQ || op == OP_NE) | |
724 | fn = filter_pred_16; | |
725 | else if (field_is_signed) | |
726 | fn = filter_pred_s16; | |
727 | else | |
728 | fn = filter_pred_u16; | |
729 | break; | |
730 | case 1: | |
731 | if (op == OP_EQ || op == OP_NE) | |
732 | fn = filter_pred_8; | |
733 | else if (field_is_signed) | |
734 | fn = filter_pred_s8; | |
735 | else | |
736 | fn = filter_pred_u8; | |
737 | break; | |
738 | } | |
739 | ||
740 | return fn; | |
741 | } | |
742 | ||
743 | static int filter_add_pred(struct filter_parse_state *ps, | |
744 | struct ftrace_event_call *call, | |
1f9963cb LZ |
745 | struct filter_pred *pred, |
746 | bool dry_run) | |
7ce7e424 TZ |
747 | { |
748 | struct ftrace_event_field *field; | |
0a19e53c | 749 | filter_pred_fn_t fn; |
f66578a7 | 750 | unsigned long long val; |
5e4904cb | 751 | int ret; |
7ce7e424 | 752 | |
8b372562 TZ |
753 | pred->fn = filter_pred_none; |
754 | ||
755 | if (pred->op == OP_AND) { | |
756 | pred->pop_n = 2; | |
1f9963cb LZ |
757 | fn = filter_pred_and; |
758 | goto add_pred_fn; | |
8b372562 TZ |
759 | } else if (pred->op == OP_OR) { |
760 | pred->pop_n = 2; | |
1f9963cb LZ |
761 | fn = filter_pred_or; |
762 | goto add_pred_fn; | |
8b372562 TZ |
763 | } |
764 | ||
7ce7e424 | 765 | field = find_event_field(call, pred->field_name); |
8b372562 TZ |
766 | if (!field) { |
767 | parse_error(ps, FILT_ERR_FIELD_NOT_FOUND, 0); | |
7ce7e424 | 768 | return -EINVAL; |
8b372562 | 769 | } |
7ce7e424 TZ |
770 | |
771 | pred->offset = field->offset; | |
772 | ||
8b372562 TZ |
773 | if (!is_legal_op(field, pred->op)) { |
774 | parse_error(ps, FILT_ERR_ILLEGAL_FIELD_OP, 0); | |
775 | return -EINVAL; | |
776 | } | |
777 | ||
aa38e9fc | 778 | if (is_string_field(field)) { |
1889d209 FW |
779 | ret = filter_build_regex(pred); |
780 | if (ret) | |
781 | return ret; | |
87a342f5 | 782 | |
1889d209 | 783 | if (field->filter_type == FILTER_STATIC_STRING) { |
e8808c10 | 784 | fn = filter_pred_string; |
1889d209 FW |
785 | pred->regex.field_len = field->size; |
786 | } else if (field->filter_type == FILTER_DYN_STRING) | |
787 | fn = filter_pred_strloc; | |
87a342f5 LZ |
788 | else { |
789 | fn = filter_pred_pchar; | |
1889d209 | 790 | pred->regex.field_len = strlen(pred->regex.pattern); |
87a342f5 | 791 | } |
9f58a159 | 792 | } else { |
5e4904cb | 793 | if (field->is_signed) |
1889d209 | 794 | ret = strict_strtoll(pred->regex.pattern, 0, &val); |
5e4904cb | 795 | else |
1889d209 | 796 | ret = strict_strtoull(pred->regex.pattern, 0, &val); |
5e4904cb | 797 | if (ret) { |
8b372562 | 798 | parse_error(ps, FILT_ERR_ILLEGAL_INTVAL, 0); |
9f58a159 | 799 | return -EINVAL; |
8b372562 | 800 | } |
f66578a7 | 801 | pred->val = val; |
7ce7e424 | 802 | |
1f9963cb LZ |
803 | fn = select_comparison_fn(pred->op, field->size, |
804 | field->is_signed); | |
805 | if (!fn) { | |
806 | parse_error(ps, FILT_ERR_INVALID_OP, 0); | |
807 | return -EINVAL; | |
808 | } | |
7ce7e424 TZ |
809 | } |
810 | ||
8b372562 TZ |
811 | if (pred->op == OP_NE) |
812 | pred->not = 1; | |
ac1adc55 | 813 | |
1f9963cb LZ |
814 | add_pred_fn: |
815 | if (!dry_run) | |
816 | return filter_add_pred_fn(ps, call, pred, fn); | |
817 | return 0; | |
cfb180f3 TZ |
818 | } |
819 | ||
8b372562 TZ |
820 | static int filter_add_subsystem_pred(struct filter_parse_state *ps, |
821 | struct event_subsystem *system, | |
822 | struct filter_pred *pred, | |
1f9963cb LZ |
823 | char *filter_string, |
824 | bool dry_run) | |
cfb180f3 | 825 | { |
a59fd602 | 826 | struct ftrace_event_call *call; |
20c8928a | 827 | int err = 0; |
1f9963cb | 828 | bool fail = true; |
cfb180f3 | 829 | |
a59fd602 | 830 | list_for_each_entry(call, &ftrace_events, list) { |
c4cff064 | 831 | |
e1112b4d | 832 | if (!call->define_fields) |
cfb180f3 TZ |
833 | continue; |
834 | ||
c4cff064 TZ |
835 | if (strcmp(call->system, system->name)) |
836 | continue; | |
837 | ||
1f9963cb LZ |
838 | if (call->filter->no_reset) |
839 | continue; | |
840 | ||
841 | err = filter_add_pred(ps, call, pred, dry_run); | |
842 | if (err) | |
843 | call->filter->no_reset = true; | |
844 | else | |
845 | fail = false; | |
846 | ||
847 | if (!dry_run) | |
848 | replace_filter_string(call->filter, filter_string); | |
cfb180f3 | 849 | } |
1f9963cb LZ |
850 | |
851 | if (fail) { | |
852 | parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0); | |
853 | return err; | |
854 | } | |
855 | return 0; | |
8b372562 TZ |
856 | } |
857 | ||
858 | static void parse_init(struct filter_parse_state *ps, | |
859 | struct filter_op *ops, | |
860 | char *infix_string) | |
861 | { | |
862 | memset(ps, '\0', sizeof(*ps)); | |
863 | ||
864 | ps->infix.string = infix_string; | |
865 | ps->infix.cnt = strlen(infix_string); | |
866 | ps->ops = ops; | |
867 | ||
868 | INIT_LIST_HEAD(&ps->opstack); | |
869 | INIT_LIST_HEAD(&ps->postfix); | |
870 | } | |
871 | ||
872 | static char infix_next(struct filter_parse_state *ps) | |
873 | { | |
874 | ps->infix.cnt--; | |
875 | ||
876 | return ps->infix.string[ps->infix.tail++]; | |
877 | } | |
878 | ||
879 | static char infix_peek(struct filter_parse_state *ps) | |
880 | { | |
881 | if (ps->infix.tail == strlen(ps->infix.string)) | |
882 | return 0; | |
883 | ||
884 | return ps->infix.string[ps->infix.tail]; | |
885 | } | |
886 | ||
887 | static void infix_advance(struct filter_parse_state *ps) | |
888 | { | |
889 | ps->infix.cnt--; | |
890 | ps->infix.tail++; | |
891 | } | |
892 | ||
893 | static inline int is_precedence_lower(struct filter_parse_state *ps, | |
894 | int a, int b) | |
895 | { | |
896 | return ps->ops[a].precedence < ps->ops[b].precedence; | |
897 | } | |
898 | ||
899 | static inline int is_op_char(struct filter_parse_state *ps, char c) | |
900 | { | |
901 | int i; | |
902 | ||
903 | for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) { | |
904 | if (ps->ops[i].string[0] == c) | |
905 | return 1; | |
906 | } | |
c4cff064 | 907 | |
0a19e53c | 908 | return 0; |
cfb180f3 TZ |
909 | } |
910 | ||
8b372562 TZ |
911 | static int infix_get_op(struct filter_parse_state *ps, char firstc) |
912 | { | |
913 | char nextc = infix_peek(ps); | |
914 | char opstr[3]; | |
915 | int i; | |
916 | ||
917 | opstr[0] = firstc; | |
918 | opstr[1] = nextc; | |
919 | opstr[2] = '\0'; | |
920 | ||
921 | for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) { | |
922 | if (!strcmp(opstr, ps->ops[i].string)) { | |
923 | infix_advance(ps); | |
924 | return ps->ops[i].id; | |
7ce7e424 | 925 | } |
8b372562 TZ |
926 | } |
927 | ||
928 | opstr[1] = '\0'; | |
929 | ||
930 | for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) { | |
931 | if (!strcmp(opstr, ps->ops[i].string)) | |
932 | return ps->ops[i].id; | |
933 | } | |
934 | ||
935 | return OP_NONE; | |
936 | } | |
937 | ||
938 | static inline void clear_operand_string(struct filter_parse_state *ps) | |
939 | { | |
940 | memset(ps->operand.string, '\0', MAX_FILTER_STR_VAL); | |
941 | ps->operand.tail = 0; | |
942 | } | |
943 | ||
944 | static inline int append_operand_char(struct filter_parse_state *ps, char c) | |
945 | { | |
5872144f | 946 | if (ps->operand.tail == MAX_FILTER_STR_VAL - 1) |
8b372562 TZ |
947 | return -EINVAL; |
948 | ||
949 | ps->operand.string[ps->operand.tail++] = c; | |
950 | ||
951 | return 0; | |
952 | } | |
953 | ||
954 | static int filter_opstack_push(struct filter_parse_state *ps, int op) | |
955 | { | |
956 | struct opstack_op *opstack_op; | |
957 | ||
958 | opstack_op = kmalloc(sizeof(*opstack_op), GFP_KERNEL); | |
959 | if (!opstack_op) | |
960 | return -ENOMEM; | |
961 | ||
962 | opstack_op->op = op; | |
963 | list_add(&opstack_op->list, &ps->opstack); | |
964 | ||
965 | return 0; | |
966 | } | |
967 | ||
968 | static int filter_opstack_empty(struct filter_parse_state *ps) | |
969 | { | |
970 | return list_empty(&ps->opstack); | |
971 | } | |
972 | ||
973 | static int filter_opstack_top(struct filter_parse_state *ps) | |
974 | { | |
975 | struct opstack_op *opstack_op; | |
976 | ||
977 | if (filter_opstack_empty(ps)) | |
978 | return OP_NONE; | |
979 | ||
980 | opstack_op = list_first_entry(&ps->opstack, struct opstack_op, list); | |
981 | ||
982 | return opstack_op->op; | |
983 | } | |
984 | ||
985 | static int filter_opstack_pop(struct filter_parse_state *ps) | |
986 | { | |
987 | struct opstack_op *opstack_op; | |
988 | int op; | |
989 | ||
990 | if (filter_opstack_empty(ps)) | |
991 | return OP_NONE; | |
992 | ||
993 | opstack_op = list_first_entry(&ps->opstack, struct opstack_op, list); | |
994 | op = opstack_op->op; | |
995 | list_del(&opstack_op->list); | |
996 | ||
997 | kfree(opstack_op); | |
998 | ||
999 | return op; | |
1000 | } | |
1001 | ||
1002 | static void filter_opstack_clear(struct filter_parse_state *ps) | |
1003 | { | |
1004 | while (!filter_opstack_empty(ps)) | |
1005 | filter_opstack_pop(ps); | |
1006 | } | |
1007 | ||
1008 | static char *curr_operand(struct filter_parse_state *ps) | |
1009 | { | |
1010 | return ps->operand.string; | |
1011 | } | |
1012 | ||
1013 | static int postfix_append_operand(struct filter_parse_state *ps, char *operand) | |
1014 | { | |
1015 | struct postfix_elt *elt; | |
1016 | ||
1017 | elt = kmalloc(sizeof(*elt), GFP_KERNEL); | |
1018 | if (!elt) | |
1019 | return -ENOMEM; | |
1020 | ||
1021 | elt->op = OP_NONE; | |
1022 | elt->operand = kstrdup(operand, GFP_KERNEL); | |
1023 | if (!elt->operand) { | |
1024 | kfree(elt); | |
1025 | return -ENOMEM; | |
1026 | } | |
1027 | ||
1028 | list_add_tail(&elt->list, &ps->postfix); | |
1029 | ||
1030 | return 0; | |
1031 | } | |
1032 | ||
1033 | static int postfix_append_op(struct filter_parse_state *ps, int op) | |
1034 | { | |
1035 | struct postfix_elt *elt; | |
1036 | ||
1037 | elt = kmalloc(sizeof(*elt), GFP_KERNEL); | |
1038 | if (!elt) | |
1039 | return -ENOMEM; | |
1040 | ||
1041 | elt->op = op; | |
1042 | elt->operand = NULL; | |
1043 | ||
1044 | list_add_tail(&elt->list, &ps->postfix); | |
1045 | ||
1046 | return 0; | |
1047 | } | |
1048 | ||
1049 | static void postfix_clear(struct filter_parse_state *ps) | |
1050 | { | |
1051 | struct postfix_elt *elt; | |
1052 | ||
1053 | while (!list_empty(&ps->postfix)) { | |
1054 | elt = list_first_entry(&ps->postfix, struct postfix_elt, list); | |
8b372562 | 1055 | list_del(&elt->list); |
8ad80731 LZ |
1056 | kfree(elt->operand); |
1057 | kfree(elt); | |
8b372562 TZ |
1058 | } |
1059 | } | |
1060 | ||
1061 | static int filter_parse(struct filter_parse_state *ps) | |
1062 | { | |
5928c3cc | 1063 | int in_string = 0; |
8b372562 TZ |
1064 | int op, top_op; |
1065 | char ch; | |
1066 | ||
1067 | while ((ch = infix_next(ps))) { | |
5928c3cc FW |
1068 | if (ch == '"') { |
1069 | in_string ^= 1; | |
1070 | continue; | |
1071 | } | |
1072 | ||
1073 | if (in_string) | |
1074 | goto parse_operand; | |
1075 | ||
8b372562 TZ |
1076 | if (isspace(ch)) |
1077 | continue; | |
1078 | ||
1079 | if (is_op_char(ps, ch)) { | |
1080 | op = infix_get_op(ps, ch); | |
1081 | if (op == OP_NONE) { | |
1082 | parse_error(ps, FILT_ERR_INVALID_OP, 0); | |
7ce7e424 TZ |
1083 | return -EINVAL; |
1084 | } | |
8b372562 TZ |
1085 | |
1086 | if (strlen(curr_operand(ps))) { | |
1087 | postfix_append_operand(ps, curr_operand(ps)); | |
1088 | clear_operand_string(ps); | |
1089 | } | |
1090 | ||
1091 | while (!filter_opstack_empty(ps)) { | |
1092 | top_op = filter_opstack_top(ps); | |
1093 | if (!is_precedence_lower(ps, top_op, op)) { | |
1094 | top_op = filter_opstack_pop(ps); | |
1095 | postfix_append_op(ps, top_op); | |
1096 | continue; | |
1097 | } | |
1098 | break; | |
1099 | } | |
1100 | ||
1101 | filter_opstack_push(ps, op); | |
7ce7e424 TZ |
1102 | continue; |
1103 | } | |
8b372562 TZ |
1104 | |
1105 | if (ch == '(') { | |
1106 | filter_opstack_push(ps, OP_OPEN_PAREN); | |
1107 | continue; | |
1108 | } | |
1109 | ||
1110 | if (ch == ')') { | |
1111 | if (strlen(curr_operand(ps))) { | |
1112 | postfix_append_operand(ps, curr_operand(ps)); | |
1113 | clear_operand_string(ps); | |
1114 | } | |
1115 | ||
1116 | top_op = filter_opstack_pop(ps); | |
1117 | while (top_op != OP_NONE) { | |
1118 | if (top_op == OP_OPEN_PAREN) | |
1119 | break; | |
1120 | postfix_append_op(ps, top_op); | |
1121 | top_op = filter_opstack_pop(ps); | |
1122 | } | |
1123 | if (top_op == OP_NONE) { | |
1124 | parse_error(ps, FILT_ERR_UNBALANCED_PAREN, 0); | |
1125 | return -EINVAL; | |
7ce7e424 | 1126 | } |
7ce7e424 TZ |
1127 | continue; |
1128 | } | |
5928c3cc | 1129 | parse_operand: |
8b372562 TZ |
1130 | if (append_operand_char(ps, ch)) { |
1131 | parse_error(ps, FILT_ERR_OPERAND_TOO_LONG, 0); | |
1132 | return -EINVAL; | |
1133 | } | |
1134 | } | |
1135 | ||
1136 | if (strlen(curr_operand(ps))) | |
1137 | postfix_append_operand(ps, curr_operand(ps)); | |
1138 | ||
1139 | while (!filter_opstack_empty(ps)) { | |
1140 | top_op = filter_opstack_pop(ps); | |
1141 | if (top_op == OP_NONE) | |
1142 | break; | |
1143 | if (top_op == OP_OPEN_PAREN) { | |
1144 | parse_error(ps, FILT_ERR_UNBALANCED_PAREN, 0); | |
1145 | return -EINVAL; | |
1146 | } | |
1147 | postfix_append_op(ps, top_op); | |
1148 | } | |
1149 | ||
1150 | return 0; | |
1151 | } | |
1152 | ||
1153 | static struct filter_pred *create_pred(int op, char *operand1, char *operand2) | |
1154 | { | |
1155 | struct filter_pred *pred; | |
1156 | ||
1157 | pred = kzalloc(sizeof(*pred), GFP_KERNEL); | |
1158 | if (!pred) | |
1159 | return NULL; | |
1160 | ||
1161 | pred->field_name = kstrdup(operand1, GFP_KERNEL); | |
1162 | if (!pred->field_name) { | |
1163 | kfree(pred); | |
1164 | return NULL; | |
1165 | } | |
1166 | ||
1889d209 FW |
1167 | strcpy(pred->regex.pattern, operand2); |
1168 | pred->regex.len = strlen(pred->regex.pattern); | |
8b372562 TZ |
1169 | |
1170 | pred->op = op; | |
1171 | ||
1172 | return pred; | |
1173 | } | |
1174 | ||
1175 | static struct filter_pred *create_logical_pred(int op) | |
1176 | { | |
1177 | struct filter_pred *pred; | |
1178 | ||
1179 | pred = kzalloc(sizeof(*pred), GFP_KERNEL); | |
1180 | if (!pred) | |
1181 | return NULL; | |
1182 | ||
1183 | pred->op = op; | |
1184 | ||
1185 | return pred; | |
1186 | } | |
1187 | ||
1188 | static int check_preds(struct filter_parse_state *ps) | |
1189 | { | |
1190 | int n_normal_preds = 0, n_logical_preds = 0; | |
1191 | struct postfix_elt *elt; | |
1192 | ||
1193 | list_for_each_entry(elt, &ps->postfix, list) { | |
1194 | if (elt->op == OP_NONE) | |
1195 | continue; | |
1196 | ||
1197 | if (elt->op == OP_AND || elt->op == OP_OR) { | |
1198 | n_logical_preds++; | |
1199 | continue; | |
7ce7e424 | 1200 | } |
8b372562 | 1201 | n_normal_preds++; |
7ce7e424 TZ |
1202 | } |
1203 | ||
8b372562 TZ |
1204 | if (!n_normal_preds || n_logical_preds >= n_normal_preds) { |
1205 | parse_error(ps, FILT_ERR_INVALID_FILTER, 0); | |
bcabd91c LZ |
1206 | return -EINVAL; |
1207 | } | |
1208 | ||
8b372562 TZ |
1209 | return 0; |
1210 | } | |
f66578a7 | 1211 | |
8b372562 TZ |
1212 | static int replace_preds(struct event_subsystem *system, |
1213 | struct ftrace_event_call *call, | |
1214 | struct filter_parse_state *ps, | |
1f9963cb LZ |
1215 | char *filter_string, |
1216 | bool dry_run) | |
8b372562 TZ |
1217 | { |
1218 | char *operand1 = NULL, *operand2 = NULL; | |
1219 | struct filter_pred *pred; | |
1220 | struct postfix_elt *elt; | |
1221 | int err; | |
1f9963cb | 1222 | int n_preds = 0; |
8b372562 TZ |
1223 | |
1224 | err = check_preds(ps); | |
1225 | if (err) | |
1226 | return err; | |
1227 | ||
1228 | list_for_each_entry(elt, &ps->postfix, list) { | |
1229 | if (elt->op == OP_NONE) { | |
1230 | if (!operand1) | |
1231 | operand1 = elt->operand; | |
1232 | else if (!operand2) | |
1233 | operand2 = elt->operand; | |
1234 | else { | |
1235 | parse_error(ps, FILT_ERR_TOO_MANY_OPERANDS, 0); | |
1236 | return -EINVAL; | |
1237 | } | |
1238 | continue; | |
1239 | } | |
1240 | ||
1f9963cb LZ |
1241 | if (n_preds++ == MAX_FILTER_PRED) { |
1242 | parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0); | |
1243 | return -ENOSPC; | |
1244 | } | |
1245 | ||
8b372562 TZ |
1246 | if (elt->op == OP_AND || elt->op == OP_OR) { |
1247 | pred = create_logical_pred(elt->op); | |
1f9963cb | 1248 | goto add_pred; |
8b372562 TZ |
1249 | } |
1250 | ||
1251 | if (!operand1 || !operand2) { | |
1252 | parse_error(ps, FILT_ERR_MISSING_FIELD, 0); | |
1253 | return -EINVAL; | |
1254 | } | |
1255 | ||
1256 | pred = create_pred(elt->op, operand1, operand2); | |
1f9963cb | 1257 | add_pred: |
fb82ad71 TZ |
1258 | if (!pred) |
1259 | return -ENOMEM; | |
c5cb1836 | 1260 | if (call) |
1f9963cb | 1261 | err = filter_add_pred(ps, call, pred, false); |
c5cb1836 | 1262 | else |
8b372562 | 1263 | err = filter_add_subsystem_pred(ps, system, pred, |
1f9963cb | 1264 | filter_string, dry_run); |
c5cb1836 | 1265 | filter_free_pred(pred); |
8b372562 TZ |
1266 | if (err) |
1267 | return err; | |
1268 | ||
1269 | operand1 = operand2 = NULL; | |
1270 | } | |
7ce7e424 | 1271 | |
7ce7e424 TZ |
1272 | return 0; |
1273 | } | |
1274 | ||
8b372562 TZ |
1275 | int apply_event_filter(struct ftrace_event_call *call, char *filter_string) |
1276 | { | |
1277 | int err; | |
1278 | ||
1279 | struct filter_parse_state *ps; | |
1280 | ||
00e95830 | 1281 | mutex_lock(&event_mutex); |
8b372562 | 1282 | |
8e254c1d LZ |
1283 | err = init_preds(call); |
1284 | if (err) | |
1285 | goto out_unlock; | |
1286 | ||
8b372562 TZ |
1287 | if (!strcmp(strstrip(filter_string), "0")) { |
1288 | filter_disable_preds(call); | |
1289 | remove_filter_string(call->filter); | |
00e95830 | 1290 | mutex_unlock(&event_mutex); |
8b372562 TZ |
1291 | return 0; |
1292 | } | |
1293 | ||
8cd995b6 | 1294 | err = -ENOMEM; |
8b372562 TZ |
1295 | ps = kzalloc(sizeof(*ps), GFP_KERNEL); |
1296 | if (!ps) | |
8cd995b6 | 1297 | goto out_unlock; |
8b372562 TZ |
1298 | |
1299 | filter_disable_preds(call); | |
1300 | replace_filter_string(call->filter, filter_string); | |
1301 | ||
1302 | parse_init(ps, filter_ops, filter_string); | |
1303 | err = filter_parse(ps); | |
1304 | if (err) { | |
1305 | append_filter_err(ps, call->filter); | |
1306 | goto out; | |
1307 | } | |
1308 | ||
1f9963cb | 1309 | err = replace_preds(NULL, call, ps, filter_string, false); |
8b372562 TZ |
1310 | if (err) |
1311 | append_filter_err(ps, call->filter); | |
1312 | ||
1313 | out: | |
1314 | filter_opstack_clear(ps); | |
1315 | postfix_clear(ps); | |
1316 | kfree(ps); | |
8cd995b6 | 1317 | out_unlock: |
00e95830 | 1318 | mutex_unlock(&event_mutex); |
8b372562 TZ |
1319 | |
1320 | return err; | |
1321 | } | |
1322 | ||
1323 | int apply_subsystem_event_filter(struct event_subsystem *system, | |
1324 | char *filter_string) | |
1325 | { | |
1326 | int err; | |
1327 | ||
1328 | struct filter_parse_state *ps; | |
1329 | ||
00e95830 | 1330 | mutex_lock(&event_mutex); |
8b372562 | 1331 | |
8e254c1d LZ |
1332 | err = init_subsystem_preds(system); |
1333 | if (err) | |
1334 | goto out_unlock; | |
1335 | ||
8b372562 | 1336 | if (!strcmp(strstrip(filter_string), "0")) { |
1f9963cb | 1337 | filter_free_subsystem_preds(system, FILTER_DISABLE_ALL); |
8b372562 | 1338 | remove_filter_string(system->filter); |
00e95830 | 1339 | mutex_unlock(&event_mutex); |
8b372562 TZ |
1340 | return 0; |
1341 | } | |
1342 | ||
8cd995b6 | 1343 | err = -ENOMEM; |
8b372562 TZ |
1344 | ps = kzalloc(sizeof(*ps), GFP_KERNEL); |
1345 | if (!ps) | |
8cd995b6 | 1346 | goto out_unlock; |
8b372562 | 1347 | |
8b372562 TZ |
1348 | replace_filter_string(system->filter, filter_string); |
1349 | ||
1350 | parse_init(ps, filter_ops, filter_string); | |
1351 | err = filter_parse(ps); | |
1352 | if (err) { | |
1353 | append_filter_err(ps, system->filter); | |
1354 | goto out; | |
1355 | } | |
1356 | ||
1f9963cb LZ |
1357 | filter_free_subsystem_preds(system, FILTER_INIT_NO_RESET); |
1358 | ||
1359 | /* try to see the filter can be applied to which events */ | |
1360 | err = replace_preds(system, NULL, ps, filter_string, true); | |
1361 | if (err) { | |
1362 | append_filter_err(ps, system->filter); | |
1363 | goto out; | |
1364 | } | |
1365 | ||
1366 | filter_free_subsystem_preds(system, FILTER_SKIP_NO_RESET); | |
1367 | ||
1368 | /* really apply the filter to the events */ | |
1369 | err = replace_preds(system, NULL, ps, filter_string, false); | |
1370 | if (err) { | |
8b372562 | 1371 | append_filter_err(ps, system->filter); |
1f9963cb LZ |
1372 | filter_free_subsystem_preds(system, 2); |
1373 | } | |
8b372562 TZ |
1374 | |
1375 | out: | |
1376 | filter_opstack_clear(ps); | |
1377 | postfix_clear(ps); | |
1378 | kfree(ps); | |
8cd995b6 | 1379 | out_unlock: |
00e95830 | 1380 | mutex_unlock(&event_mutex); |
8b372562 TZ |
1381 | |
1382 | return err; | |
1383 | } | |
7ce7e424 | 1384 |