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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> |
6fb2915d | 24 | #include <linux/perf_event.h> |
5a0e3ad6 | 25 | #include <linux/slab.h> |
7ce7e424 TZ |
26 | |
27 | #include "trace.h" | |
4bda2d51 | 28 | #include "trace_output.h" |
7ce7e424 | 29 | |
8b372562 | 30 | enum filter_op_ids |
7ce7e424 | 31 | { |
8b372562 TZ |
32 | OP_OR, |
33 | OP_AND, | |
b0f1a59a | 34 | OP_GLOB, |
8b372562 TZ |
35 | OP_NE, |
36 | OP_EQ, | |
37 | OP_LT, | |
38 | OP_LE, | |
39 | OP_GT, | |
40 | OP_GE, | |
41 | OP_NONE, | |
42 | OP_OPEN_PAREN, | |
43 | }; | |
44 | ||
45 | struct filter_op { | |
46 | int id; | |
47 | char *string; | |
48 | int precedence; | |
49 | }; | |
50 | ||
51 | static struct filter_op filter_ops[] = { | |
b0f1a59a LZ |
52 | { OP_OR, "||", 1 }, |
53 | { OP_AND, "&&", 2 }, | |
54 | { OP_GLOB, "~", 4 }, | |
55 | { OP_NE, "!=", 4 }, | |
56 | { OP_EQ, "==", 4 }, | |
57 | { OP_LT, "<", 5 }, | |
58 | { OP_LE, "<=", 5 }, | |
59 | { OP_GT, ">", 5 }, | |
60 | { OP_GE, ">=", 5 }, | |
61 | { OP_NONE, "OP_NONE", 0 }, | |
62 | { OP_OPEN_PAREN, "(", 0 }, | |
8b372562 TZ |
63 | }; |
64 | ||
65 | enum { | |
66 | FILT_ERR_NONE, | |
67 | FILT_ERR_INVALID_OP, | |
68 | FILT_ERR_UNBALANCED_PAREN, | |
69 | FILT_ERR_TOO_MANY_OPERANDS, | |
70 | FILT_ERR_OPERAND_TOO_LONG, | |
71 | FILT_ERR_FIELD_NOT_FOUND, | |
72 | FILT_ERR_ILLEGAL_FIELD_OP, | |
73 | FILT_ERR_ILLEGAL_INTVAL, | |
74 | FILT_ERR_BAD_SUBSYS_FILTER, | |
75 | FILT_ERR_TOO_MANY_PREDS, | |
76 | FILT_ERR_MISSING_FIELD, | |
77 | FILT_ERR_INVALID_FILTER, | |
78 | }; | |
79 | ||
80 | static char *err_text[] = { | |
81 | "No error", | |
82 | "Invalid operator", | |
83 | "Unbalanced parens", | |
84 | "Too many operands", | |
85 | "Operand too long", | |
86 | "Field not found", | |
87 | "Illegal operation for field type", | |
88 | "Illegal integer value", | |
89 | "Couldn't find or set field in one of a subsystem's events", | |
90 | "Too many terms in predicate expression", | |
91 | "Missing field name and/or value", | |
92 | "Meaningless filter expression", | |
93 | }; | |
94 | ||
95 | struct opstack_op { | |
96 | int op; | |
97 | struct list_head list; | |
98 | }; | |
99 | ||
100 | struct postfix_elt { | |
101 | int op; | |
102 | char *operand; | |
103 | struct list_head list; | |
104 | }; | |
105 | ||
106 | struct filter_parse_state { | |
107 | struct filter_op *ops; | |
108 | struct list_head opstack; | |
109 | struct list_head postfix; | |
110 | int lasterr; | |
111 | int lasterr_pos; | |
112 | ||
113 | struct { | |
114 | char *string; | |
115 | unsigned int cnt; | |
116 | unsigned int tail; | |
117 | } infix; | |
118 | ||
119 | struct { | |
120 | char string[MAX_FILTER_STR_VAL]; | |
121 | int pos; | |
122 | unsigned int tail; | |
123 | } operand; | |
124 | }; | |
125 | ||
61e9dea2 SR |
126 | struct pred_stack { |
127 | struct filter_pred **preds; | |
128 | int index; | |
129 | }; | |
130 | ||
197e2eab | 131 | #define DEFINE_COMPARISON_PRED(type) \ |
58d9a597 | 132 | static int filter_pred_##type(struct filter_pred *pred, void *event) \ |
197e2eab LZ |
133 | { \ |
134 | type *addr = (type *)(event + pred->offset); \ | |
135 | type val = (type)pred->val; \ | |
136 | int match = 0; \ | |
137 | \ | |
138 | switch (pred->op) { \ | |
139 | case OP_LT: \ | |
140 | match = (*addr < val); \ | |
141 | break; \ | |
142 | case OP_LE: \ | |
143 | match = (*addr <= val); \ | |
144 | break; \ | |
145 | case OP_GT: \ | |
146 | match = (*addr > val); \ | |
147 | break; \ | |
148 | case OP_GE: \ | |
149 | match = (*addr >= val); \ | |
150 | break; \ | |
151 | default: \ | |
152 | break; \ | |
153 | } \ | |
154 | \ | |
155 | return match; \ | |
156 | } | |
157 | ||
158 | #define DEFINE_EQUALITY_PRED(size) \ | |
58d9a597 | 159 | static int filter_pred_##size(struct filter_pred *pred, void *event) \ |
197e2eab LZ |
160 | { \ |
161 | u##size *addr = (u##size *)(event + pred->offset); \ | |
162 | u##size val = (u##size)pred->val; \ | |
163 | int match; \ | |
164 | \ | |
165 | match = (val == *addr) ^ pred->not; \ | |
166 | \ | |
167 | return match; \ | |
168 | } | |
169 | ||
8b372562 TZ |
170 | DEFINE_COMPARISON_PRED(s64); |
171 | DEFINE_COMPARISON_PRED(u64); | |
172 | DEFINE_COMPARISON_PRED(s32); | |
173 | DEFINE_COMPARISON_PRED(u32); | |
174 | DEFINE_COMPARISON_PRED(s16); | |
175 | DEFINE_COMPARISON_PRED(u16); | |
176 | DEFINE_COMPARISON_PRED(s8); | |
177 | DEFINE_COMPARISON_PRED(u8); | |
178 | ||
179 | DEFINE_EQUALITY_PRED(64); | |
180 | DEFINE_EQUALITY_PRED(32); | |
181 | DEFINE_EQUALITY_PRED(16); | |
182 | DEFINE_EQUALITY_PRED(8); | |
183 | ||
e8808c10 | 184 | /* Filter predicate for fixed sized arrays of characters */ |
58d9a597 | 185 | static int filter_pred_string(struct filter_pred *pred, void *event) |
7ce7e424 TZ |
186 | { |
187 | char *addr = (char *)(event + pred->offset); | |
188 | int cmp, match; | |
189 | ||
1889d209 | 190 | cmp = pred->regex.match(addr, &pred->regex, pred->regex.field_len); |
7ce7e424 | 191 | |
1889d209 | 192 | match = cmp ^ pred->not; |
7ce7e424 TZ |
193 | |
194 | return match; | |
195 | } | |
196 | ||
87a342f5 | 197 | /* Filter predicate for char * pointers */ |
58d9a597 | 198 | static int filter_pred_pchar(struct filter_pred *pred, void *event) |
87a342f5 LZ |
199 | { |
200 | char **addr = (char **)(event + pred->offset); | |
201 | int cmp, match; | |
16da27a8 | 202 | int len = strlen(*addr) + 1; /* including tailing '\0' */ |
87a342f5 | 203 | |
16da27a8 | 204 | cmp = pred->regex.match(*addr, &pred->regex, len); |
87a342f5 | 205 | |
1889d209 | 206 | match = cmp ^ pred->not; |
87a342f5 LZ |
207 | |
208 | return match; | |
209 | } | |
210 | ||
e8808c10 FW |
211 | /* |
212 | * Filter predicate for dynamic sized arrays of characters. | |
213 | * These are implemented through a list of strings at the end | |
214 | * of the entry. | |
215 | * Also each of these strings have a field in the entry which | |
216 | * contains its offset from the beginning of the entry. | |
217 | * We have then first to get this field, dereference it | |
218 | * and add it to the address of the entry, and at last we have | |
219 | * the address of the string. | |
220 | */ | |
58d9a597 | 221 | static int filter_pred_strloc(struct filter_pred *pred, void *event) |
e8808c10 | 222 | { |
7d536cb3 LZ |
223 | u32 str_item = *(u32 *)(event + pred->offset); |
224 | int str_loc = str_item & 0xffff; | |
225 | int str_len = str_item >> 16; | |
e8808c10 FW |
226 | char *addr = (char *)(event + str_loc); |
227 | int cmp, match; | |
228 | ||
1889d209 | 229 | cmp = pred->regex.match(addr, &pred->regex, str_len); |
e8808c10 | 230 | |
1889d209 | 231 | match = cmp ^ pred->not; |
e8808c10 FW |
232 | |
233 | return match; | |
234 | } | |
235 | ||
58d9a597 | 236 | static int filter_pred_none(struct filter_pred *pred, void *event) |
0a19e53c TZ |
237 | { |
238 | return 0; | |
239 | } | |
240 | ||
d1303dd1 LZ |
241 | /* |
242 | * regex_match_foo - Basic regex callbacks | |
243 | * | |
244 | * @str: the string to be searched | |
245 | * @r: the regex structure containing the pattern string | |
246 | * @len: the length of the string to be searched (including '\0') | |
247 | * | |
248 | * Note: | |
249 | * - @str might not be NULL-terminated if it's of type DYN_STRING | |
250 | * or STATIC_STRING | |
251 | */ | |
252 | ||
1889d209 FW |
253 | static int regex_match_full(char *str, struct regex *r, int len) |
254 | { | |
255 | if (strncmp(str, r->pattern, len) == 0) | |
256 | return 1; | |
257 | return 0; | |
258 | } | |
259 | ||
260 | static int regex_match_front(char *str, struct regex *r, int len) | |
261 | { | |
285caad4 | 262 | if (strncmp(str, r->pattern, r->len) == 0) |
1889d209 FW |
263 | return 1; |
264 | return 0; | |
265 | } | |
266 | ||
267 | static int regex_match_middle(char *str, struct regex *r, int len) | |
268 | { | |
b2af211f | 269 | if (strnstr(str, r->pattern, len)) |
1889d209 FW |
270 | return 1; |
271 | return 0; | |
272 | } | |
273 | ||
274 | static int regex_match_end(char *str, struct regex *r, int len) | |
275 | { | |
a3291c14 | 276 | int strlen = len - 1; |
1889d209 | 277 | |
a3291c14 LZ |
278 | if (strlen >= r->len && |
279 | memcmp(str + strlen - r->len, r->pattern, r->len) == 0) | |
1889d209 FW |
280 | return 1; |
281 | return 0; | |
282 | } | |
283 | ||
3f6fe06d FW |
284 | /** |
285 | * filter_parse_regex - parse a basic regex | |
286 | * @buff: the raw regex | |
287 | * @len: length of the regex | |
288 | * @search: will point to the beginning of the string to compare | |
289 | * @not: tell whether the match will have to be inverted | |
290 | * | |
291 | * This passes in a buffer containing a regex and this function will | |
1889d209 FW |
292 | * set search to point to the search part of the buffer and |
293 | * return the type of search it is (see enum above). | |
294 | * This does modify buff. | |
295 | * | |
296 | * Returns enum type. | |
297 | * search returns the pointer to use for comparison. | |
298 | * not returns 1 if buff started with a '!' | |
299 | * 0 otherwise. | |
300 | */ | |
3f6fe06d | 301 | enum regex_type filter_parse_regex(char *buff, int len, char **search, int *not) |
1889d209 FW |
302 | { |
303 | int type = MATCH_FULL; | |
304 | int i; | |
305 | ||
306 | if (buff[0] == '!') { | |
307 | *not = 1; | |
308 | buff++; | |
309 | len--; | |
310 | } else | |
311 | *not = 0; | |
312 | ||
313 | *search = buff; | |
314 | ||
315 | for (i = 0; i < len; i++) { | |
316 | if (buff[i] == '*') { | |
317 | if (!i) { | |
318 | *search = buff + 1; | |
319 | type = MATCH_END_ONLY; | |
320 | } else { | |
321 | if (type == MATCH_END_ONLY) | |
322 | type = MATCH_MIDDLE_ONLY; | |
323 | else | |
324 | type = MATCH_FRONT_ONLY; | |
325 | buff[i] = 0; | |
326 | break; | |
327 | } | |
328 | } | |
329 | } | |
330 | ||
331 | return type; | |
332 | } | |
333 | ||
b0f1a59a | 334 | static void filter_build_regex(struct filter_pred *pred) |
1889d209 FW |
335 | { |
336 | struct regex *r = &pred->regex; | |
b0f1a59a LZ |
337 | char *search; |
338 | enum regex_type type = MATCH_FULL; | |
339 | int not = 0; | |
340 | ||
341 | if (pred->op == OP_GLOB) { | |
342 | type = filter_parse_regex(r->pattern, r->len, &search, ¬); | |
343 | r->len = strlen(search); | |
344 | memmove(r->pattern, search, r->len+1); | |
345 | } | |
1889d209 FW |
346 | |
347 | switch (type) { | |
348 | case MATCH_FULL: | |
349 | r->match = regex_match_full; | |
350 | break; | |
351 | case MATCH_FRONT_ONLY: | |
352 | r->match = regex_match_front; | |
353 | break; | |
354 | case MATCH_MIDDLE_ONLY: | |
355 | r->match = regex_match_middle; | |
356 | break; | |
357 | case MATCH_END_ONLY: | |
358 | r->match = regex_match_end; | |
359 | break; | |
360 | } | |
361 | ||
362 | pred->not ^= not; | |
1889d209 FW |
363 | } |
364 | ||
61e9dea2 SR |
365 | enum move_type { |
366 | MOVE_DOWN, | |
367 | MOVE_UP_FROM_LEFT, | |
368 | MOVE_UP_FROM_RIGHT | |
369 | }; | |
370 | ||
371 | static struct filter_pred * | |
372 | get_pred_parent(struct filter_pred *pred, struct filter_pred *preds, | |
373 | int index, enum move_type *move) | |
374 | { | |
375 | if (pred->parent & FILTER_PRED_IS_RIGHT) | |
376 | *move = MOVE_UP_FROM_RIGHT; | |
377 | else | |
378 | *move = MOVE_UP_FROM_LEFT; | |
379 | pred = &preds[pred->parent & ~FILTER_PRED_IS_RIGHT]; | |
380 | ||
381 | return pred; | |
382 | } | |
383 | ||
43cd4145 SR |
384 | /* |
385 | * A series of AND or ORs where found together. Instead of | |
386 | * climbing up and down the tree branches, an array of the | |
387 | * ops were made in order of checks. We can just move across | |
388 | * the array and short circuit if needed. | |
389 | */ | |
390 | static int process_ops(struct filter_pred *preds, | |
391 | struct filter_pred *op, void *rec) | |
392 | { | |
393 | struct filter_pred *pred; | |
1ef1d1c2 | 394 | int match = 0; |
43cd4145 | 395 | int type; |
43cd4145 SR |
396 | int i; |
397 | ||
398 | /* | |
399 | * Micro-optimization: We set type to true if op | |
400 | * is an OR and false otherwise (AND). Then we | |
401 | * just need to test if the match is equal to | |
402 | * the type, and if it is, we can short circuit the | |
403 | * rest of the checks: | |
404 | * | |
405 | * if ((match && op->op == OP_OR) || | |
406 | * (!match && op->op == OP_AND)) | |
407 | * return match; | |
408 | */ | |
409 | type = op->op == OP_OR; | |
410 | ||
411 | for (i = 0; i < op->val; i++) { | |
412 | pred = &preds[op->ops[i]]; | |
413 | match = pred->fn(pred, rec); | |
414 | if (!!match == type) | |
415 | return match; | |
416 | } | |
417 | return match; | |
418 | } | |
419 | ||
7ce7e424 | 420 | /* return 1 if event matches, 0 otherwise (discard) */ |
6fb2915d | 421 | int filter_match_preds(struct event_filter *filter, void *rec) |
7ce7e424 | 422 | { |
61e9dea2 SR |
423 | int match = -1; |
424 | enum move_type move = MOVE_DOWN; | |
74e9e58c | 425 | struct filter_pred *preds; |
7ce7e424 | 426 | struct filter_pred *pred; |
61e9dea2 | 427 | struct filter_pred *root; |
75b8e982 | 428 | int n_preds; |
61e9dea2 | 429 | int done = 0; |
7ce7e424 | 430 | |
6d54057d | 431 | /* no filter is considered a match */ |
75b8e982 SR |
432 | if (!filter) |
433 | return 1; | |
434 | ||
435 | n_preds = filter->n_preds; | |
436 | ||
6d54057d SR |
437 | if (!n_preds) |
438 | return 1; | |
439 | ||
c9c53ca0 | 440 | /* |
61e9dea2 | 441 | * n_preds, root and filter->preds are protect with preemption disabled. |
c9c53ca0 SR |
442 | */ |
443 | preds = rcu_dereference_sched(filter->preds); | |
61e9dea2 SR |
444 | root = rcu_dereference_sched(filter->root); |
445 | if (!root) | |
446 | return 1; | |
c9c53ca0 | 447 | |
61e9dea2 SR |
448 | pred = root; |
449 | ||
450 | /* match is currently meaningless */ | |
451 | match = -1; | |
452 | ||
453 | do { | |
454 | switch (move) { | |
455 | case MOVE_DOWN: | |
456 | /* only AND and OR have children */ | |
457 | if (pred->left != FILTER_PRED_INVALID) { | |
43cd4145 SR |
458 | /* If ops is set, then it was folded. */ |
459 | if (!pred->ops) { | |
460 | /* keep going to down the left side */ | |
461 | pred = &preds[pred->left]; | |
462 | continue; | |
463 | } | |
464 | /* We can treat folded ops as a leaf node */ | |
465 | match = process_ops(preds, pred, rec); | |
466 | } else | |
467 | match = pred->fn(pred, rec); | |
61e9dea2 SR |
468 | /* If this pred is the only pred */ |
469 | if (pred == root) | |
470 | break; | |
471 | pred = get_pred_parent(pred, preds, | |
472 | pred->parent, &move); | |
473 | continue; | |
474 | case MOVE_UP_FROM_LEFT: | |
55719274 SR |
475 | /* |
476 | * Check for short circuits. | |
477 | * | |
478 | * Optimization: !!match == (pred->op == OP_OR) | |
479 | * is the same as: | |
480 | * if ((match && pred->op == OP_OR) || | |
481 | * (!match && pred->op == OP_AND)) | |
482 | */ | |
483 | if (!!match == (pred->op == OP_OR)) { | |
61e9dea2 SR |
484 | if (pred == root) |
485 | break; | |
486 | pred = get_pred_parent(pred, preds, | |
487 | pred->parent, &move); | |
488 | continue; | |
489 | } | |
490 | /* now go down the right side of the tree. */ | |
491 | pred = &preds[pred->right]; | |
492 | move = MOVE_DOWN; | |
493 | continue; | |
494 | case MOVE_UP_FROM_RIGHT: | |
495 | /* We finished this equation. */ | |
496 | if (pred == root) | |
497 | break; | |
498 | pred = get_pred_parent(pred, preds, | |
499 | pred->parent, &move); | |
0a19e53c | 500 | continue; |
8b372562 | 501 | } |
61e9dea2 SR |
502 | done = 1; |
503 | } while (!done); | |
7ce7e424 | 504 | |
61e9dea2 | 505 | return match; |
7ce7e424 | 506 | } |
17c873ec | 507 | EXPORT_SYMBOL_GPL(filter_match_preds); |
7ce7e424 | 508 | |
8b372562 | 509 | static void parse_error(struct filter_parse_state *ps, int err, int pos) |
7ce7e424 | 510 | { |
8b372562 TZ |
511 | ps->lasterr = err; |
512 | ps->lasterr_pos = pos; | |
513 | } | |
7ce7e424 | 514 | |
8b372562 TZ |
515 | static void remove_filter_string(struct event_filter *filter) |
516 | { | |
75b8e982 SR |
517 | if (!filter) |
518 | return; | |
519 | ||
8b372562 TZ |
520 | kfree(filter->filter_string); |
521 | filter->filter_string = NULL; | |
522 | } | |
523 | ||
524 | static int replace_filter_string(struct event_filter *filter, | |
525 | char *filter_string) | |
526 | { | |
527 | kfree(filter->filter_string); | |
528 | filter->filter_string = kstrdup(filter_string, GFP_KERNEL); | |
529 | if (!filter->filter_string) | |
530 | return -ENOMEM; | |
531 | ||
532 | return 0; | |
533 | } | |
534 | ||
535 | static int append_filter_string(struct event_filter *filter, | |
536 | char *string) | |
537 | { | |
538 | int newlen; | |
539 | char *new_filter_string; | |
540 | ||
541 | BUG_ON(!filter->filter_string); | |
542 | newlen = strlen(filter->filter_string) + strlen(string) + 1; | |
543 | new_filter_string = kmalloc(newlen, GFP_KERNEL); | |
544 | if (!new_filter_string) | |
545 | return -ENOMEM; | |
546 | ||
547 | strcpy(new_filter_string, filter->filter_string); | |
548 | strcat(new_filter_string, string); | |
549 | kfree(filter->filter_string); | |
550 | filter->filter_string = new_filter_string; | |
551 | ||
552 | return 0; | |
553 | } | |
554 | ||
555 | static void append_filter_err(struct filter_parse_state *ps, | |
556 | struct event_filter *filter) | |
557 | { | |
558 | int pos = ps->lasterr_pos; | |
559 | char *buf, *pbuf; | |
560 | ||
561 | buf = (char *)__get_free_page(GFP_TEMPORARY); | |
562 | if (!buf) | |
4bda2d51 | 563 | return; |
7ce7e424 | 564 | |
8b372562 TZ |
565 | append_filter_string(filter, "\n"); |
566 | memset(buf, ' ', PAGE_SIZE); | |
567 | if (pos > PAGE_SIZE - 128) | |
568 | pos = 0; | |
569 | buf[pos] = '^'; | |
570 | pbuf = &buf[pos] + 1; | |
571 | ||
572 | sprintf(pbuf, "\nparse_error: %s\n", err_text[ps->lasterr]); | |
573 | append_filter_string(filter, buf); | |
574 | free_page((unsigned long) buf); | |
7ce7e424 TZ |
575 | } |
576 | ||
8b372562 | 577 | void print_event_filter(struct ftrace_event_call *call, struct trace_seq *s) |
ac1adc55 | 578 | { |
75b8e982 | 579 | struct event_filter *filter; |
8b372562 | 580 | |
00e95830 | 581 | mutex_lock(&event_mutex); |
75b8e982 | 582 | filter = call->filter; |
8e254c1d | 583 | if (filter && filter->filter_string) |
8b372562 TZ |
584 | trace_seq_printf(s, "%s\n", filter->filter_string); |
585 | else | |
586 | trace_seq_printf(s, "none\n"); | |
00e95830 | 587 | mutex_unlock(&event_mutex); |
ac1adc55 TZ |
588 | } |
589 | ||
8b372562 | 590 | void print_subsystem_event_filter(struct event_subsystem *system, |
ac1adc55 TZ |
591 | struct trace_seq *s) |
592 | { | |
75b8e982 | 593 | struct event_filter *filter; |
8b372562 | 594 | |
00e95830 | 595 | mutex_lock(&event_mutex); |
75b8e982 | 596 | filter = system->filter; |
8e254c1d | 597 | if (filter && filter->filter_string) |
8b372562 TZ |
598 | trace_seq_printf(s, "%s\n", filter->filter_string); |
599 | else | |
600 | trace_seq_printf(s, "none\n"); | |
00e95830 | 601 | mutex_unlock(&event_mutex); |
ac1adc55 TZ |
602 | } |
603 | ||
7ce7e424 | 604 | static struct ftrace_event_field * |
8728fe50 | 605 | __find_event_field(struct list_head *head, char *name) |
7ce7e424 | 606 | { |
1fc2d5c1 | 607 | struct ftrace_event_field *field; |
7ce7e424 | 608 | |
2e33af02 | 609 | list_for_each_entry(field, head, link) { |
7ce7e424 TZ |
610 | if (!strcmp(field->name, name)) |
611 | return field; | |
612 | } | |
613 | ||
614 | return NULL; | |
615 | } | |
616 | ||
8728fe50 LZ |
617 | static struct ftrace_event_field * |
618 | find_event_field(struct ftrace_event_call *call, char *name) | |
619 | { | |
620 | struct ftrace_event_field *field; | |
621 | struct list_head *head; | |
622 | ||
623 | field = __find_event_field(&ftrace_common_fields, name); | |
624 | if (field) | |
625 | return field; | |
626 | ||
627 | head = trace_get_fields(call); | |
628 | return __find_event_field(head, name); | |
629 | } | |
630 | ||
8b372562 | 631 | static void filter_free_pred(struct filter_pred *pred) |
7ce7e424 | 632 | { |
7ce7e424 | 633 | kfree(pred->field_name); |
7ce7e424 TZ |
634 | } |
635 | ||
0a19e53c TZ |
636 | static void filter_clear_pred(struct filter_pred *pred) |
637 | { | |
638 | kfree(pred->field_name); | |
639 | pred->field_name = NULL; | |
1889d209 | 640 | pred->regex.len = 0; |
0a19e53c TZ |
641 | } |
642 | ||
61e9dea2 SR |
643 | static int __alloc_pred_stack(struct pred_stack *stack, int n_preds) |
644 | { | |
645 | stack->preds = kzalloc(sizeof(*stack->preds)*(n_preds + 1), GFP_KERNEL); | |
646 | if (!stack->preds) | |
647 | return -ENOMEM; | |
648 | stack->index = n_preds; | |
649 | return 0; | |
650 | } | |
651 | ||
652 | static void __free_pred_stack(struct pred_stack *stack) | |
653 | { | |
654 | kfree(stack->preds); | |
655 | stack->index = 0; | |
656 | } | |
657 | ||
658 | static int __push_pred_stack(struct pred_stack *stack, | |
659 | struct filter_pred *pred) | |
660 | { | |
661 | int index = stack->index; | |
662 | ||
663 | if (WARN_ON(index == 0)) | |
664 | return -ENOSPC; | |
665 | ||
666 | stack->preds[--index] = pred; | |
667 | stack->index = index; | |
668 | return 0; | |
669 | } | |
670 | ||
671 | static struct filter_pred * | |
672 | __pop_pred_stack(struct pred_stack *stack) | |
673 | { | |
674 | struct filter_pred *pred; | |
675 | int index = stack->index; | |
676 | ||
677 | pred = stack->preds[index++]; | |
678 | if (!pred) | |
679 | return NULL; | |
680 | ||
681 | stack->index = index; | |
682 | return pred; | |
683 | } | |
684 | ||
685 | static int filter_set_pred(struct event_filter *filter, | |
686 | int idx, | |
687 | struct pred_stack *stack, | |
0a19e53c TZ |
688 | struct filter_pred *src, |
689 | filter_pred_fn_t fn) | |
690 | { | |
61e9dea2 SR |
691 | struct filter_pred *dest = &filter->preds[idx]; |
692 | struct filter_pred *left; | |
693 | struct filter_pred *right; | |
694 | ||
0a19e53c | 695 | *dest = *src; |
8b372562 TZ |
696 | if (src->field_name) { |
697 | dest->field_name = kstrdup(src->field_name, GFP_KERNEL); | |
698 | if (!dest->field_name) | |
699 | return -ENOMEM; | |
700 | } | |
0a19e53c | 701 | dest->fn = fn; |
61e9dea2 | 702 | dest->index = idx; |
0a19e53c | 703 | |
61e9dea2 SR |
704 | if (dest->op == OP_OR || dest->op == OP_AND) { |
705 | right = __pop_pred_stack(stack); | |
706 | left = __pop_pred_stack(stack); | |
707 | if (!left || !right) | |
708 | return -EINVAL; | |
43cd4145 SR |
709 | /* |
710 | * If both children can be folded | |
711 | * and they are the same op as this op or a leaf, | |
712 | * then this op can be folded. | |
713 | */ | |
714 | if (left->index & FILTER_PRED_FOLD && | |
715 | (left->op == dest->op || | |
716 | left->left == FILTER_PRED_INVALID) && | |
717 | right->index & FILTER_PRED_FOLD && | |
718 | (right->op == dest->op || | |
719 | right->left == FILTER_PRED_INVALID)) | |
720 | dest->index |= FILTER_PRED_FOLD; | |
721 | ||
722 | dest->left = left->index & ~FILTER_PRED_FOLD; | |
723 | dest->right = right->index & ~FILTER_PRED_FOLD; | |
724 | left->parent = dest->index & ~FILTER_PRED_FOLD; | |
61e9dea2 | 725 | right->parent = dest->index | FILTER_PRED_IS_RIGHT; |
43cd4145 | 726 | } else { |
61e9dea2 SR |
727 | /* |
728 | * Make dest->left invalid to be used as a quick | |
729 | * way to know this is a leaf node. | |
730 | */ | |
731 | dest->left = FILTER_PRED_INVALID; | |
732 | ||
43cd4145 SR |
733 | /* All leafs allow folding the parent ops. */ |
734 | dest->index |= FILTER_PRED_FOLD; | |
735 | } | |
736 | ||
61e9dea2 | 737 | return __push_pred_stack(stack, dest); |
0a19e53c TZ |
738 | } |
739 | ||
c9c53ca0 SR |
740 | static void __free_preds(struct event_filter *filter) |
741 | { | |
742 | int i; | |
743 | ||
744 | if (filter->preds) { | |
74e9e58c SR |
745 | for (i = 0; i < filter->a_preds; i++) |
746 | kfree(filter->preds[i].field_name); | |
c9c53ca0 SR |
747 | kfree(filter->preds); |
748 | filter->preds = NULL; | |
749 | } | |
750 | filter->a_preds = 0; | |
751 | filter->n_preds = 0; | |
752 | } | |
753 | ||
75b8e982 | 754 | static void filter_disable(struct ftrace_event_call *call) |
7ce7e424 | 755 | { |
553552ce | 756 | call->flags &= ~TRACE_EVENT_FL_FILTERED; |
0a19e53c TZ |
757 | } |
758 | ||
c9c53ca0 | 759 | static void __free_filter(struct event_filter *filter) |
2df75e41 | 760 | { |
8e254c1d LZ |
761 | if (!filter) |
762 | return; | |
763 | ||
c9c53ca0 | 764 | __free_preds(filter); |
57be8887 | 765 | kfree(filter->filter_string); |
2df75e41 | 766 | kfree(filter); |
6fb2915d LZ |
767 | } |
768 | ||
75b8e982 SR |
769 | /* |
770 | * Called when destroying the ftrace_event_call. | |
771 | * The call is being freed, so we do not need to worry about | |
772 | * the call being currently used. This is for module code removing | |
773 | * the tracepoints from within it. | |
774 | */ | |
6fb2915d LZ |
775 | void destroy_preds(struct ftrace_event_call *call) |
776 | { | |
c9c53ca0 | 777 | __free_filter(call->filter); |
2df75e41 LZ |
778 | call->filter = NULL; |
779 | } | |
780 | ||
c9c53ca0 | 781 | static struct event_filter *__alloc_filter(void) |
0a19e53c | 782 | { |
30e673b2 | 783 | struct event_filter *filter; |
0a19e53c | 784 | |
6fb2915d | 785 | filter = kzalloc(sizeof(*filter), GFP_KERNEL); |
c9c53ca0 SR |
786 | return filter; |
787 | } | |
788 | ||
789 | static int __alloc_preds(struct event_filter *filter, int n_preds) | |
790 | { | |
791 | struct filter_pred *pred; | |
792 | int i; | |
793 | ||
4defe682 SR |
794 | if (filter->preds) |
795 | __free_preds(filter); | |
796 | ||
797 | filter->preds = | |
798 | kzalloc(sizeof(*filter->preds) * n_preds, GFP_KERNEL); | |
c9c53ca0 | 799 | |
30e673b2 | 800 | if (!filter->preds) |
c9c53ca0 SR |
801 | return -ENOMEM; |
802 | ||
4defe682 SR |
803 | filter->a_preds = n_preds; |
804 | filter->n_preds = 0; | |
30e673b2 | 805 | |
c9c53ca0 | 806 | for (i = 0; i < n_preds; i++) { |
74e9e58c | 807 | pred = &filter->preds[i]; |
0a19e53c | 808 | pred->fn = filter_pred_none; |
0a19e53c TZ |
809 | } |
810 | ||
c9c53ca0 | 811 | return 0; |
6fb2915d LZ |
812 | } |
813 | ||
75b8e982 | 814 | static void filter_free_subsystem_preds(struct event_subsystem *system) |
8e254c1d LZ |
815 | { |
816 | struct ftrace_event_call *call; | |
8e254c1d LZ |
817 | |
818 | list_for_each_entry(call, &ftrace_events, list) { | |
8f082018 | 819 | if (strcmp(call->class->system, system->name) != 0) |
8e254c1d LZ |
820 | continue; |
821 | ||
75b8e982 SR |
822 | filter_disable(call); |
823 | remove_filter_string(call->filter); | |
8e254c1d | 824 | } |
8e254c1d | 825 | } |
7ce7e424 | 826 | |
75b8e982 | 827 | static void filter_free_subsystem_filters(struct event_subsystem *system) |
cfb180f3 | 828 | { |
a59fd602 | 829 | struct ftrace_event_call *call; |
cfb180f3 | 830 | |
a59fd602 | 831 | list_for_each_entry(call, &ftrace_events, list) { |
8f082018 | 832 | if (strcmp(call->class->system, system->name) != 0) |
8e254c1d | 833 | continue; |
75b8e982 SR |
834 | __free_filter(call->filter); |
835 | call->filter = NULL; | |
cfb180f3 TZ |
836 | } |
837 | } | |
838 | ||
8b372562 TZ |
839 | static int filter_add_pred_fn(struct filter_parse_state *ps, |
840 | struct ftrace_event_call *call, | |
6fb2915d | 841 | struct event_filter *filter, |
ac1adc55 | 842 | struct filter_pred *pred, |
61e9dea2 | 843 | struct pred_stack *stack, |
ac1adc55 | 844 | filter_pred_fn_t fn) |
7ce7e424 | 845 | { |
0a19e53c | 846 | int idx, err; |
7ce7e424 | 847 | |
c9c53ca0 | 848 | if (WARN_ON(filter->n_preds == filter->a_preds)) { |
8b372562 | 849 | parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0); |
0a19e53c | 850 | return -ENOSPC; |
8b372562 | 851 | } |
7ce7e424 | 852 | |
30e673b2 | 853 | idx = filter->n_preds; |
74e9e58c | 854 | filter_clear_pred(&filter->preds[idx]); |
61e9dea2 | 855 | err = filter_set_pred(filter, idx, stack, pred, fn); |
0a19e53c TZ |
856 | if (err) |
857 | return err; | |
858 | ||
30e673b2 | 859 | filter->n_preds++; |
7ce7e424 | 860 | |
0a19e53c | 861 | return 0; |
7ce7e424 TZ |
862 | } |
863 | ||
aa38e9fc | 864 | int filter_assign_type(const char *type) |
7ce7e424 | 865 | { |
7fcb7c47 LZ |
866 | if (strstr(type, "__data_loc") && strstr(type, "char")) |
867 | return FILTER_DYN_STRING; | |
868 | ||
7ce7e424 | 869 | if (strchr(type, '[') && strstr(type, "char")) |
e8808c10 FW |
870 | return FILTER_STATIC_STRING; |
871 | ||
aa38e9fc LZ |
872 | return FILTER_OTHER; |
873 | } | |
874 | ||
875 | static bool is_string_field(struct ftrace_event_field *field) | |
876 | { | |
877 | return field->filter_type == FILTER_DYN_STRING || | |
87a342f5 LZ |
878 | field->filter_type == FILTER_STATIC_STRING || |
879 | field->filter_type == FILTER_PTR_STRING; | |
7ce7e424 TZ |
880 | } |
881 | ||
8b372562 TZ |
882 | static int is_legal_op(struct ftrace_event_field *field, int op) |
883 | { | |
b0f1a59a LZ |
884 | if (is_string_field(field) && |
885 | (op != OP_EQ && op != OP_NE && op != OP_GLOB)) | |
886 | return 0; | |
887 | if (!is_string_field(field) && op == OP_GLOB) | |
8b372562 TZ |
888 | return 0; |
889 | ||
890 | return 1; | |
891 | } | |
892 | ||
893 | static filter_pred_fn_t select_comparison_fn(int op, int field_size, | |
894 | int field_is_signed) | |
895 | { | |
896 | filter_pred_fn_t fn = NULL; | |
897 | ||
898 | switch (field_size) { | |
899 | case 8: | |
900 | if (op == OP_EQ || op == OP_NE) | |
901 | fn = filter_pred_64; | |
902 | else if (field_is_signed) | |
903 | fn = filter_pred_s64; | |
904 | else | |
905 | fn = filter_pred_u64; | |
906 | break; | |
907 | case 4: | |
908 | if (op == OP_EQ || op == OP_NE) | |
909 | fn = filter_pred_32; | |
910 | else if (field_is_signed) | |
911 | fn = filter_pred_s32; | |
912 | else | |
913 | fn = filter_pred_u32; | |
914 | break; | |
915 | case 2: | |
916 | if (op == OP_EQ || op == OP_NE) | |
917 | fn = filter_pred_16; | |
918 | else if (field_is_signed) | |
919 | fn = filter_pred_s16; | |
920 | else | |
921 | fn = filter_pred_u16; | |
922 | break; | |
923 | case 1: | |
924 | if (op == OP_EQ || op == OP_NE) | |
925 | fn = filter_pred_8; | |
926 | else if (field_is_signed) | |
927 | fn = filter_pred_s8; | |
928 | else | |
929 | fn = filter_pred_u8; | |
930 | break; | |
931 | } | |
932 | ||
933 | return fn; | |
934 | } | |
935 | ||
936 | static int filter_add_pred(struct filter_parse_state *ps, | |
937 | struct ftrace_event_call *call, | |
6fb2915d | 938 | struct event_filter *filter, |
1f9963cb | 939 | struct filter_pred *pred, |
61e9dea2 | 940 | struct pred_stack *stack, |
1f9963cb | 941 | bool dry_run) |
7ce7e424 TZ |
942 | { |
943 | struct ftrace_event_field *field; | |
0a19e53c | 944 | filter_pred_fn_t fn; |
f66578a7 | 945 | unsigned long long val; |
5e4904cb | 946 | int ret; |
7ce7e424 | 947 | |
58d9a597 | 948 | fn = pred->fn = filter_pred_none; |
8b372562 | 949 | |
61e9dea2 | 950 | if (pred->op == OP_AND) |
1f9963cb | 951 | goto add_pred_fn; |
61e9dea2 | 952 | else if (pred->op == OP_OR) |
1f9963cb | 953 | goto add_pred_fn; |
8b372562 | 954 | |
7ce7e424 | 955 | field = find_event_field(call, pred->field_name); |
8b372562 TZ |
956 | if (!field) { |
957 | parse_error(ps, FILT_ERR_FIELD_NOT_FOUND, 0); | |
7ce7e424 | 958 | return -EINVAL; |
8b372562 | 959 | } |
7ce7e424 TZ |
960 | |
961 | pred->offset = field->offset; | |
962 | ||
8b372562 TZ |
963 | if (!is_legal_op(field, pred->op)) { |
964 | parse_error(ps, FILT_ERR_ILLEGAL_FIELD_OP, 0); | |
965 | return -EINVAL; | |
966 | } | |
967 | ||
aa38e9fc | 968 | if (is_string_field(field)) { |
b0f1a59a | 969 | filter_build_regex(pred); |
87a342f5 | 970 | |
1889d209 | 971 | if (field->filter_type == FILTER_STATIC_STRING) { |
e8808c10 | 972 | fn = filter_pred_string; |
1889d209 FW |
973 | pred->regex.field_len = field->size; |
974 | } else if (field->filter_type == FILTER_DYN_STRING) | |
b0f1a59a | 975 | fn = filter_pred_strloc; |
16da27a8 | 976 | else |
87a342f5 | 977 | fn = filter_pred_pchar; |
9f58a159 | 978 | } else { |
5e4904cb | 979 | if (field->is_signed) |
1889d209 | 980 | ret = strict_strtoll(pred->regex.pattern, 0, &val); |
5e4904cb | 981 | else |
1889d209 | 982 | ret = strict_strtoull(pred->regex.pattern, 0, &val); |
5e4904cb | 983 | if (ret) { |
8b372562 | 984 | parse_error(ps, FILT_ERR_ILLEGAL_INTVAL, 0); |
9f58a159 | 985 | return -EINVAL; |
8b372562 | 986 | } |
f66578a7 | 987 | pred->val = val; |
7ce7e424 | 988 | |
1f9963cb LZ |
989 | fn = select_comparison_fn(pred->op, field->size, |
990 | field->is_signed); | |
991 | if (!fn) { | |
992 | parse_error(ps, FILT_ERR_INVALID_OP, 0); | |
993 | return -EINVAL; | |
994 | } | |
7ce7e424 TZ |
995 | } |
996 | ||
8b372562 TZ |
997 | if (pred->op == OP_NE) |
998 | pred->not = 1; | |
ac1adc55 | 999 | |
1f9963cb LZ |
1000 | add_pred_fn: |
1001 | if (!dry_run) | |
61e9dea2 | 1002 | return filter_add_pred_fn(ps, call, filter, pred, stack, fn); |
1f9963cb | 1003 | return 0; |
cfb180f3 TZ |
1004 | } |
1005 | ||
8b372562 TZ |
1006 | static void parse_init(struct filter_parse_state *ps, |
1007 | struct filter_op *ops, | |
1008 | char *infix_string) | |
1009 | { | |
1010 | memset(ps, '\0', sizeof(*ps)); | |
1011 | ||
1012 | ps->infix.string = infix_string; | |
1013 | ps->infix.cnt = strlen(infix_string); | |
1014 | ps->ops = ops; | |
1015 | ||
1016 | INIT_LIST_HEAD(&ps->opstack); | |
1017 | INIT_LIST_HEAD(&ps->postfix); | |
1018 | } | |
1019 | ||
1020 | static char infix_next(struct filter_parse_state *ps) | |
1021 | { | |
1022 | ps->infix.cnt--; | |
1023 | ||
1024 | return ps->infix.string[ps->infix.tail++]; | |
1025 | } | |
1026 | ||
1027 | static char infix_peek(struct filter_parse_state *ps) | |
1028 | { | |
1029 | if (ps->infix.tail == strlen(ps->infix.string)) | |
1030 | return 0; | |
1031 | ||
1032 | return ps->infix.string[ps->infix.tail]; | |
1033 | } | |
1034 | ||
1035 | static void infix_advance(struct filter_parse_state *ps) | |
1036 | { | |
1037 | ps->infix.cnt--; | |
1038 | ps->infix.tail++; | |
1039 | } | |
1040 | ||
1041 | static inline int is_precedence_lower(struct filter_parse_state *ps, | |
1042 | int a, int b) | |
1043 | { | |
1044 | return ps->ops[a].precedence < ps->ops[b].precedence; | |
1045 | } | |
1046 | ||
1047 | static inline int is_op_char(struct filter_parse_state *ps, char c) | |
1048 | { | |
1049 | int i; | |
1050 | ||
1051 | for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) { | |
1052 | if (ps->ops[i].string[0] == c) | |
1053 | return 1; | |
1054 | } | |
c4cff064 | 1055 | |
0a19e53c | 1056 | return 0; |
cfb180f3 TZ |
1057 | } |
1058 | ||
8b372562 TZ |
1059 | static int infix_get_op(struct filter_parse_state *ps, char firstc) |
1060 | { | |
1061 | char nextc = infix_peek(ps); | |
1062 | char opstr[3]; | |
1063 | int i; | |
1064 | ||
1065 | opstr[0] = firstc; | |
1066 | opstr[1] = nextc; | |
1067 | opstr[2] = '\0'; | |
1068 | ||
1069 | for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) { | |
1070 | if (!strcmp(opstr, ps->ops[i].string)) { | |
1071 | infix_advance(ps); | |
1072 | return ps->ops[i].id; | |
7ce7e424 | 1073 | } |
8b372562 TZ |
1074 | } |
1075 | ||
1076 | opstr[1] = '\0'; | |
1077 | ||
1078 | for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) { | |
1079 | if (!strcmp(opstr, ps->ops[i].string)) | |
1080 | return ps->ops[i].id; | |
1081 | } | |
1082 | ||
1083 | return OP_NONE; | |
1084 | } | |
1085 | ||
1086 | static inline void clear_operand_string(struct filter_parse_state *ps) | |
1087 | { | |
1088 | memset(ps->operand.string, '\0', MAX_FILTER_STR_VAL); | |
1089 | ps->operand.tail = 0; | |
1090 | } | |
1091 | ||
1092 | static inline int append_operand_char(struct filter_parse_state *ps, char c) | |
1093 | { | |
5872144f | 1094 | if (ps->operand.tail == MAX_FILTER_STR_VAL - 1) |
8b372562 TZ |
1095 | return -EINVAL; |
1096 | ||
1097 | ps->operand.string[ps->operand.tail++] = c; | |
1098 | ||
1099 | return 0; | |
1100 | } | |
1101 | ||
1102 | static int filter_opstack_push(struct filter_parse_state *ps, int op) | |
1103 | { | |
1104 | struct opstack_op *opstack_op; | |
1105 | ||
1106 | opstack_op = kmalloc(sizeof(*opstack_op), GFP_KERNEL); | |
1107 | if (!opstack_op) | |
1108 | return -ENOMEM; | |
1109 | ||
1110 | opstack_op->op = op; | |
1111 | list_add(&opstack_op->list, &ps->opstack); | |
1112 | ||
1113 | return 0; | |
1114 | } | |
1115 | ||
1116 | static int filter_opstack_empty(struct filter_parse_state *ps) | |
1117 | { | |
1118 | return list_empty(&ps->opstack); | |
1119 | } | |
1120 | ||
1121 | static int filter_opstack_top(struct filter_parse_state *ps) | |
1122 | { | |
1123 | struct opstack_op *opstack_op; | |
1124 | ||
1125 | if (filter_opstack_empty(ps)) | |
1126 | return OP_NONE; | |
1127 | ||
1128 | opstack_op = list_first_entry(&ps->opstack, struct opstack_op, list); | |
1129 | ||
1130 | return opstack_op->op; | |
1131 | } | |
1132 | ||
1133 | static int filter_opstack_pop(struct filter_parse_state *ps) | |
1134 | { | |
1135 | struct opstack_op *opstack_op; | |
1136 | int op; | |
1137 | ||
1138 | if (filter_opstack_empty(ps)) | |
1139 | return OP_NONE; | |
1140 | ||
1141 | opstack_op = list_first_entry(&ps->opstack, struct opstack_op, list); | |
1142 | op = opstack_op->op; | |
1143 | list_del(&opstack_op->list); | |
1144 | ||
1145 | kfree(opstack_op); | |
1146 | ||
1147 | return op; | |
1148 | } | |
1149 | ||
1150 | static void filter_opstack_clear(struct filter_parse_state *ps) | |
1151 | { | |
1152 | while (!filter_opstack_empty(ps)) | |
1153 | filter_opstack_pop(ps); | |
1154 | } | |
1155 | ||
1156 | static char *curr_operand(struct filter_parse_state *ps) | |
1157 | { | |
1158 | return ps->operand.string; | |
1159 | } | |
1160 | ||
1161 | static int postfix_append_operand(struct filter_parse_state *ps, char *operand) | |
1162 | { | |
1163 | struct postfix_elt *elt; | |
1164 | ||
1165 | elt = kmalloc(sizeof(*elt), GFP_KERNEL); | |
1166 | if (!elt) | |
1167 | return -ENOMEM; | |
1168 | ||
1169 | elt->op = OP_NONE; | |
1170 | elt->operand = kstrdup(operand, GFP_KERNEL); | |
1171 | if (!elt->operand) { | |
1172 | kfree(elt); | |
1173 | return -ENOMEM; | |
1174 | } | |
1175 | ||
1176 | list_add_tail(&elt->list, &ps->postfix); | |
1177 | ||
1178 | return 0; | |
1179 | } | |
1180 | ||
1181 | static int postfix_append_op(struct filter_parse_state *ps, int op) | |
1182 | { | |
1183 | struct postfix_elt *elt; | |
1184 | ||
1185 | elt = kmalloc(sizeof(*elt), GFP_KERNEL); | |
1186 | if (!elt) | |
1187 | return -ENOMEM; | |
1188 | ||
1189 | elt->op = op; | |
1190 | elt->operand = NULL; | |
1191 | ||
1192 | list_add_tail(&elt->list, &ps->postfix); | |
1193 | ||
1194 | return 0; | |
1195 | } | |
1196 | ||
1197 | static void postfix_clear(struct filter_parse_state *ps) | |
1198 | { | |
1199 | struct postfix_elt *elt; | |
1200 | ||
1201 | while (!list_empty(&ps->postfix)) { | |
1202 | elt = list_first_entry(&ps->postfix, struct postfix_elt, list); | |
8b372562 | 1203 | list_del(&elt->list); |
8ad80731 LZ |
1204 | kfree(elt->operand); |
1205 | kfree(elt); | |
8b372562 TZ |
1206 | } |
1207 | } | |
1208 | ||
1209 | static int filter_parse(struct filter_parse_state *ps) | |
1210 | { | |
5928c3cc | 1211 | int in_string = 0; |
8b372562 TZ |
1212 | int op, top_op; |
1213 | char ch; | |
1214 | ||
1215 | while ((ch = infix_next(ps))) { | |
5928c3cc FW |
1216 | if (ch == '"') { |
1217 | in_string ^= 1; | |
1218 | continue; | |
1219 | } | |
1220 | ||
1221 | if (in_string) | |
1222 | goto parse_operand; | |
1223 | ||
8b372562 TZ |
1224 | if (isspace(ch)) |
1225 | continue; | |
1226 | ||
1227 | if (is_op_char(ps, ch)) { | |
1228 | op = infix_get_op(ps, ch); | |
1229 | if (op == OP_NONE) { | |
1230 | parse_error(ps, FILT_ERR_INVALID_OP, 0); | |
7ce7e424 TZ |
1231 | return -EINVAL; |
1232 | } | |
8b372562 TZ |
1233 | |
1234 | if (strlen(curr_operand(ps))) { | |
1235 | postfix_append_operand(ps, curr_operand(ps)); | |
1236 | clear_operand_string(ps); | |
1237 | } | |
1238 | ||
1239 | while (!filter_opstack_empty(ps)) { | |
1240 | top_op = filter_opstack_top(ps); | |
1241 | if (!is_precedence_lower(ps, top_op, op)) { | |
1242 | top_op = filter_opstack_pop(ps); | |
1243 | postfix_append_op(ps, top_op); | |
1244 | continue; | |
1245 | } | |
1246 | break; | |
1247 | } | |
1248 | ||
1249 | filter_opstack_push(ps, op); | |
7ce7e424 TZ |
1250 | continue; |
1251 | } | |
8b372562 TZ |
1252 | |
1253 | if (ch == '(') { | |
1254 | filter_opstack_push(ps, OP_OPEN_PAREN); | |
1255 | continue; | |
1256 | } | |
1257 | ||
1258 | if (ch == ')') { | |
1259 | if (strlen(curr_operand(ps))) { | |
1260 | postfix_append_operand(ps, curr_operand(ps)); | |
1261 | clear_operand_string(ps); | |
1262 | } | |
1263 | ||
1264 | top_op = filter_opstack_pop(ps); | |
1265 | while (top_op != OP_NONE) { | |
1266 | if (top_op == OP_OPEN_PAREN) | |
1267 | break; | |
1268 | postfix_append_op(ps, top_op); | |
1269 | top_op = filter_opstack_pop(ps); | |
1270 | } | |
1271 | if (top_op == OP_NONE) { | |
1272 | parse_error(ps, FILT_ERR_UNBALANCED_PAREN, 0); | |
1273 | return -EINVAL; | |
7ce7e424 | 1274 | } |
7ce7e424 TZ |
1275 | continue; |
1276 | } | |
5928c3cc | 1277 | parse_operand: |
8b372562 TZ |
1278 | if (append_operand_char(ps, ch)) { |
1279 | parse_error(ps, FILT_ERR_OPERAND_TOO_LONG, 0); | |
1280 | return -EINVAL; | |
1281 | } | |
1282 | } | |
1283 | ||
1284 | if (strlen(curr_operand(ps))) | |
1285 | postfix_append_operand(ps, curr_operand(ps)); | |
1286 | ||
1287 | while (!filter_opstack_empty(ps)) { | |
1288 | top_op = filter_opstack_pop(ps); | |
1289 | if (top_op == OP_NONE) | |
1290 | break; | |
1291 | if (top_op == OP_OPEN_PAREN) { | |
1292 | parse_error(ps, FILT_ERR_UNBALANCED_PAREN, 0); | |
1293 | return -EINVAL; | |
1294 | } | |
1295 | postfix_append_op(ps, top_op); | |
1296 | } | |
1297 | ||
1298 | return 0; | |
1299 | } | |
1300 | ||
81570d9c JO |
1301 | static struct filter_pred *create_pred(struct filter_parse_state *ps, |
1302 | int op, char *operand1, char *operand2) | |
8b372562 | 1303 | { |
81570d9c | 1304 | static struct filter_pred pred; |
8b372562 | 1305 | |
81570d9c JO |
1306 | memset(&pred, 0, sizeof(pred)); |
1307 | pred.op = op; | |
8b372562 | 1308 | |
81570d9c JO |
1309 | if (op == OP_AND || op == OP_OR) |
1310 | return &pred; | |
1311 | ||
1312 | if (!operand1 || !operand2) { | |
1313 | parse_error(ps, FILT_ERR_MISSING_FIELD, 0); | |
8b372562 TZ |
1314 | return NULL; |
1315 | } | |
1316 | ||
81570d9c JO |
1317 | pred.field_name = kstrdup(operand1, GFP_KERNEL); |
1318 | if (!pred.field_name) | |
8b372562 TZ |
1319 | return NULL; |
1320 | ||
81570d9c JO |
1321 | strcpy(pred.regex.pattern, operand2); |
1322 | pred.regex.len = strlen(pred.regex.pattern); | |
8b372562 | 1323 | |
81570d9c | 1324 | return &pred; |
8b372562 TZ |
1325 | } |
1326 | ||
1327 | static int check_preds(struct filter_parse_state *ps) | |
1328 | { | |
1329 | int n_normal_preds = 0, n_logical_preds = 0; | |
1330 | struct postfix_elt *elt; | |
1331 | ||
1332 | list_for_each_entry(elt, &ps->postfix, list) { | |
1333 | if (elt->op == OP_NONE) | |
1334 | continue; | |
1335 | ||
1336 | if (elt->op == OP_AND || elt->op == OP_OR) { | |
1337 | n_logical_preds++; | |
1338 | continue; | |
7ce7e424 | 1339 | } |
8b372562 | 1340 | n_normal_preds++; |
7ce7e424 TZ |
1341 | } |
1342 | ||
8b372562 TZ |
1343 | if (!n_normal_preds || n_logical_preds >= n_normal_preds) { |
1344 | parse_error(ps, FILT_ERR_INVALID_FILTER, 0); | |
bcabd91c LZ |
1345 | return -EINVAL; |
1346 | } | |
1347 | ||
8b372562 TZ |
1348 | return 0; |
1349 | } | |
f66578a7 | 1350 | |
c9c53ca0 SR |
1351 | static int count_preds(struct filter_parse_state *ps) |
1352 | { | |
1353 | struct postfix_elt *elt; | |
1354 | int n_preds = 0; | |
1355 | ||
1356 | list_for_each_entry(elt, &ps->postfix, list) { | |
1357 | if (elt->op == OP_NONE) | |
1358 | continue; | |
1359 | n_preds++; | |
1360 | } | |
1361 | ||
1362 | return n_preds; | |
1363 | } | |
1364 | ||
ec126cac SR |
1365 | /* |
1366 | * The tree is walked at filtering of an event. If the tree is not correctly | |
1367 | * built, it may cause an infinite loop. Check here that the tree does | |
1368 | * indeed terminate. | |
1369 | */ | |
1370 | static int check_pred_tree(struct event_filter *filter, | |
1371 | struct filter_pred *root) | |
1372 | { | |
1373 | struct filter_pred *preds; | |
1374 | struct filter_pred *pred; | |
1375 | enum move_type move = MOVE_DOWN; | |
1376 | int count = 0; | |
1377 | int done = 0; | |
1378 | int max; | |
1379 | ||
1380 | /* | |
1381 | * The max that we can hit a node is three times. | |
1382 | * Once going down, once coming up from left, and | |
1383 | * once coming up from right. This is more than enough | |
1384 | * since leafs are only hit a single time. | |
1385 | */ | |
1386 | max = 3 * filter->n_preds; | |
1387 | ||
1388 | preds = filter->preds; | |
1389 | if (!preds) | |
1390 | return -EINVAL; | |
1391 | pred = root; | |
1392 | ||
1393 | do { | |
1394 | if (WARN_ON(count++ > max)) | |
1395 | return -EINVAL; | |
1396 | ||
1397 | switch (move) { | |
1398 | case MOVE_DOWN: | |
1399 | if (pred->left != FILTER_PRED_INVALID) { | |
1400 | pred = &preds[pred->left]; | |
1401 | continue; | |
1402 | } | |
1403 | /* A leaf at the root is just a leaf in the tree */ | |
1404 | if (pred == root) | |
1405 | break; | |
1406 | pred = get_pred_parent(pred, preds, | |
1407 | pred->parent, &move); | |
1408 | continue; | |
1409 | case MOVE_UP_FROM_LEFT: | |
1410 | pred = &preds[pred->right]; | |
1411 | move = MOVE_DOWN; | |
1412 | continue; | |
1413 | case MOVE_UP_FROM_RIGHT: | |
1414 | if (pred == root) | |
1415 | break; | |
1416 | pred = get_pred_parent(pred, preds, | |
1417 | pred->parent, &move); | |
1418 | continue; | |
1419 | } | |
1420 | done = 1; | |
1421 | } while (!done); | |
1422 | ||
1423 | /* We are fine. */ | |
1424 | return 0; | |
1425 | } | |
1426 | ||
43cd4145 SR |
1427 | static int count_leafs(struct filter_pred *preds, struct filter_pred *root) |
1428 | { | |
1429 | struct filter_pred *pred; | |
1430 | enum move_type move = MOVE_DOWN; | |
1431 | int count = 0; | |
1432 | int done = 0; | |
1433 | ||
1434 | pred = root; | |
1435 | ||
1436 | do { | |
1437 | switch (move) { | |
1438 | case MOVE_DOWN: | |
1439 | if (pred->left != FILTER_PRED_INVALID) { | |
1440 | pred = &preds[pred->left]; | |
1441 | continue; | |
1442 | } | |
1443 | /* A leaf at the root is just a leaf in the tree */ | |
1444 | if (pred == root) | |
1445 | return 1; | |
1446 | count++; | |
1447 | pred = get_pred_parent(pred, preds, | |
1448 | pred->parent, &move); | |
1449 | continue; | |
1450 | case MOVE_UP_FROM_LEFT: | |
1451 | pred = &preds[pred->right]; | |
1452 | move = MOVE_DOWN; | |
1453 | continue; | |
1454 | case MOVE_UP_FROM_RIGHT: | |
1455 | if (pred == root) | |
1456 | break; | |
1457 | pred = get_pred_parent(pred, preds, | |
1458 | pred->parent, &move); | |
1459 | continue; | |
1460 | } | |
1461 | done = 1; | |
1462 | } while (!done); | |
1463 | ||
1464 | return count; | |
1465 | } | |
1466 | ||
1467 | static int fold_pred(struct filter_pred *preds, struct filter_pred *root) | |
1468 | { | |
1469 | struct filter_pred *pred; | |
1470 | enum move_type move = MOVE_DOWN; | |
1471 | int count = 0; | |
1472 | int children; | |
1473 | int done = 0; | |
1474 | ||
1475 | /* No need to keep the fold flag */ | |
1476 | root->index &= ~FILTER_PRED_FOLD; | |
1477 | ||
1478 | /* If the root is a leaf then do nothing */ | |
1479 | if (root->left == FILTER_PRED_INVALID) | |
1480 | return 0; | |
1481 | ||
1482 | /* count the children */ | |
1483 | children = count_leafs(preds, &preds[root->left]); | |
1484 | children += count_leafs(preds, &preds[root->right]); | |
1485 | ||
1486 | root->ops = kzalloc(sizeof(*root->ops) * children, GFP_KERNEL); | |
1487 | if (!root->ops) | |
1488 | return -ENOMEM; | |
1489 | ||
1490 | root->val = children; | |
1491 | ||
1492 | pred = root; | |
1493 | do { | |
1494 | switch (move) { | |
1495 | case MOVE_DOWN: | |
1496 | if (pred->left != FILTER_PRED_INVALID) { | |
1497 | pred = &preds[pred->left]; | |
1498 | continue; | |
1499 | } | |
1500 | if (WARN_ON(count == children)) | |
1501 | return -EINVAL; | |
1502 | pred->index &= ~FILTER_PRED_FOLD; | |
1503 | root->ops[count++] = pred->index; | |
1504 | pred = get_pred_parent(pred, preds, | |
1505 | pred->parent, &move); | |
1506 | continue; | |
1507 | case MOVE_UP_FROM_LEFT: | |
1508 | pred = &preds[pred->right]; | |
1509 | move = MOVE_DOWN; | |
1510 | continue; | |
1511 | case MOVE_UP_FROM_RIGHT: | |
1512 | if (pred == root) | |
1513 | break; | |
1514 | pred = get_pred_parent(pred, preds, | |
1515 | pred->parent, &move); | |
1516 | continue; | |
1517 | } | |
1518 | done = 1; | |
1519 | } while (!done); | |
1520 | ||
1521 | return 0; | |
1522 | } | |
1523 | ||
1524 | /* | |
1525 | * To optimize the processing of the ops, if we have several "ors" or | |
1526 | * "ands" together, we can put them in an array and process them all | |
1527 | * together speeding up the filter logic. | |
1528 | */ | |
1529 | static int fold_pred_tree(struct event_filter *filter, | |
1530 | struct filter_pred *root) | |
1531 | { | |
1532 | struct filter_pred *preds; | |
1533 | struct filter_pred *pred; | |
1534 | enum move_type move = MOVE_DOWN; | |
1535 | int done = 0; | |
1536 | int err; | |
1537 | ||
1538 | preds = filter->preds; | |
1539 | if (!preds) | |
1540 | return -EINVAL; | |
1541 | pred = root; | |
1542 | ||
1543 | do { | |
1544 | switch (move) { | |
1545 | case MOVE_DOWN: | |
1546 | if (pred->index & FILTER_PRED_FOLD) { | |
1547 | err = fold_pred(preds, pred); | |
1548 | if (err) | |
1549 | return err; | |
1550 | /* Folded nodes are like leafs */ | |
1551 | } else if (pred->left != FILTER_PRED_INVALID) { | |
1552 | pred = &preds[pred->left]; | |
1553 | continue; | |
1554 | } | |
1555 | ||
1556 | /* A leaf at the root is just a leaf in the tree */ | |
1557 | if (pred == root) | |
1558 | break; | |
1559 | pred = get_pred_parent(pred, preds, | |
1560 | pred->parent, &move); | |
1561 | continue; | |
1562 | case MOVE_UP_FROM_LEFT: | |
1563 | pred = &preds[pred->right]; | |
1564 | move = MOVE_DOWN; | |
1565 | continue; | |
1566 | case MOVE_UP_FROM_RIGHT: | |
1567 | if (pred == root) | |
1568 | break; | |
1569 | pred = get_pred_parent(pred, preds, | |
1570 | pred->parent, &move); | |
1571 | continue; | |
1572 | } | |
1573 | done = 1; | |
1574 | } while (!done); | |
1575 | ||
1576 | return 0; | |
1577 | } | |
1578 | ||
fce29d15 | 1579 | static int replace_preds(struct ftrace_event_call *call, |
6fb2915d | 1580 | struct event_filter *filter, |
8b372562 | 1581 | struct filter_parse_state *ps, |
1f9963cb LZ |
1582 | char *filter_string, |
1583 | bool dry_run) | |
8b372562 TZ |
1584 | { |
1585 | char *operand1 = NULL, *operand2 = NULL; | |
1586 | struct filter_pred *pred; | |
ec126cac | 1587 | struct filter_pred *root; |
8b372562 | 1588 | struct postfix_elt *elt; |
61e9dea2 | 1589 | struct pred_stack stack = { }; /* init to NULL */ |
8b372562 | 1590 | int err; |
1f9963cb | 1591 | int n_preds = 0; |
8b372562 | 1592 | |
c9c53ca0 SR |
1593 | n_preds = count_preds(ps); |
1594 | if (n_preds >= MAX_FILTER_PRED) { | |
1595 | parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0); | |
1596 | return -ENOSPC; | |
1597 | } | |
1598 | ||
8b372562 TZ |
1599 | err = check_preds(ps); |
1600 | if (err) | |
1601 | return err; | |
1602 | ||
c9c53ca0 | 1603 | if (!dry_run) { |
61e9dea2 | 1604 | err = __alloc_pred_stack(&stack, n_preds); |
c9c53ca0 SR |
1605 | if (err) |
1606 | return err; | |
61e9dea2 SR |
1607 | err = __alloc_preds(filter, n_preds); |
1608 | if (err) | |
1609 | goto fail; | |
c9c53ca0 SR |
1610 | } |
1611 | ||
1612 | n_preds = 0; | |
8b372562 TZ |
1613 | list_for_each_entry(elt, &ps->postfix, list) { |
1614 | if (elt->op == OP_NONE) { | |
1615 | if (!operand1) | |
1616 | operand1 = elt->operand; | |
1617 | else if (!operand2) | |
1618 | operand2 = elt->operand; | |
1619 | else { | |
1620 | parse_error(ps, FILT_ERR_TOO_MANY_OPERANDS, 0); | |
61e9dea2 SR |
1621 | err = -EINVAL; |
1622 | goto fail; | |
8b372562 TZ |
1623 | } |
1624 | continue; | |
1625 | } | |
1626 | ||
c9c53ca0 | 1627 | if (WARN_ON(n_preds++ == MAX_FILTER_PRED)) { |
1f9963cb | 1628 | parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0); |
61e9dea2 SR |
1629 | err = -ENOSPC; |
1630 | goto fail; | |
1f9963cb LZ |
1631 | } |
1632 | ||
81570d9c | 1633 | pred = create_pred(ps, elt->op, operand1, operand2); |
61e9dea2 SR |
1634 | if (!pred) { |
1635 | err = -ENOMEM; | |
1636 | goto fail; | |
1637 | } | |
1638 | err = filter_add_pred(ps, call, filter, pred, &stack, dry_run); | |
c5cb1836 | 1639 | filter_free_pred(pred); |
8b372562 | 1640 | if (err) |
61e9dea2 | 1641 | goto fail; |
8b372562 TZ |
1642 | |
1643 | operand1 = operand2 = NULL; | |
1644 | } | |
7ce7e424 | 1645 | |
61e9dea2 SR |
1646 | if (!dry_run) { |
1647 | /* We should have one item left on the stack */ | |
1648 | pred = __pop_pred_stack(&stack); | |
1649 | if (!pred) | |
1650 | return -EINVAL; | |
1651 | /* This item is where we start from in matching */ | |
ec126cac | 1652 | root = pred; |
61e9dea2 SR |
1653 | /* Make sure the stack is empty */ |
1654 | pred = __pop_pred_stack(&stack); | |
1655 | if (WARN_ON(pred)) { | |
1656 | err = -EINVAL; | |
1657 | filter->root = NULL; | |
1658 | goto fail; | |
1659 | } | |
ec126cac SR |
1660 | err = check_pred_tree(filter, root); |
1661 | if (err) | |
1662 | goto fail; | |
1663 | ||
43cd4145 SR |
1664 | /* Optimize the tree */ |
1665 | err = fold_pred_tree(filter, root); | |
1666 | if (err) | |
1667 | goto fail; | |
1668 | ||
ec126cac SR |
1669 | /* We don't set root until we know it works */ |
1670 | barrier(); | |
1671 | filter->root = root; | |
61e9dea2 SR |
1672 | } |
1673 | ||
1674 | err = 0; | |
1675 | fail: | |
1676 | __free_pred_stack(&stack); | |
1677 | return err; | |
7ce7e424 TZ |
1678 | } |
1679 | ||
75b8e982 SR |
1680 | struct filter_list { |
1681 | struct list_head list; | |
1682 | struct event_filter *filter; | |
1683 | }; | |
1684 | ||
fce29d15 LZ |
1685 | static int replace_system_preds(struct event_subsystem *system, |
1686 | struct filter_parse_state *ps, | |
1687 | char *filter_string) | |
1688 | { | |
1689 | struct ftrace_event_call *call; | |
75b8e982 SR |
1690 | struct filter_list *filter_item; |
1691 | struct filter_list *tmp; | |
1692 | LIST_HEAD(filter_list); | |
fce29d15 | 1693 | bool fail = true; |
a66abe7f | 1694 | int err; |
fce29d15 LZ |
1695 | |
1696 | list_for_each_entry(call, &ftrace_events, list) { | |
1697 | ||
8f082018 | 1698 | if (strcmp(call->class->system, system->name) != 0) |
fce29d15 LZ |
1699 | continue; |
1700 | ||
75b8e982 SR |
1701 | /* |
1702 | * Try to see if the filter can be applied | |
1703 | * (filter arg is ignored on dry_run) | |
1704 | */ | |
1705 | err = replace_preds(call, NULL, ps, filter_string, true); | |
fce29d15 | 1706 | if (err) |
0fc3ca9a SR |
1707 | goto fail; |
1708 | } | |
1709 | ||
0fc3ca9a | 1710 | list_for_each_entry(call, &ftrace_events, list) { |
75b8e982 | 1711 | struct event_filter *filter; |
0fc3ca9a SR |
1712 | |
1713 | if (strcmp(call->class->system, system->name) != 0) | |
1714 | continue; | |
1715 | ||
75b8e982 SR |
1716 | filter_item = kzalloc(sizeof(*filter_item), GFP_KERNEL); |
1717 | if (!filter_item) | |
1718 | goto fail_mem; | |
0fc3ca9a | 1719 | |
75b8e982 | 1720 | list_add_tail(&filter_item->list, &filter_list); |
0fc3ca9a | 1721 | |
75b8e982 SR |
1722 | filter_item->filter = __alloc_filter(); |
1723 | if (!filter_item->filter) | |
1724 | goto fail_mem; | |
1725 | filter = filter_item->filter; | |
0fc3ca9a | 1726 | |
75b8e982 SR |
1727 | /* Can only fail on no memory */ |
1728 | err = replace_filter_string(filter, filter_string); | |
1729 | if (err) | |
1730 | goto fail_mem; | |
fce29d15 | 1731 | |
6fb2915d | 1732 | err = replace_preds(call, filter, ps, filter_string, false); |
75b8e982 SR |
1733 | if (err) { |
1734 | filter_disable(call); | |
1735 | parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0); | |
1736 | append_filter_err(ps, filter); | |
1737 | } else | |
553552ce | 1738 | call->flags |= TRACE_EVENT_FL_FILTERED; |
75b8e982 SR |
1739 | /* |
1740 | * Regardless of if this returned an error, we still | |
1741 | * replace the filter for the call. | |
1742 | */ | |
1743 | filter = call->filter; | |
1744 | call->filter = filter_item->filter; | |
1745 | filter_item->filter = filter; | |
1746 | ||
fce29d15 LZ |
1747 | fail = false; |
1748 | } | |
1749 | ||
0fc3ca9a SR |
1750 | if (fail) |
1751 | goto fail; | |
1752 | ||
75b8e982 SR |
1753 | /* |
1754 | * The calls can still be using the old filters. | |
1755 | * Do a synchronize_sched() to ensure all calls are | |
1756 | * done with them before we free them. | |
1757 | */ | |
1758 | synchronize_sched(); | |
1759 | list_for_each_entry_safe(filter_item, tmp, &filter_list, list) { | |
1760 | __free_filter(filter_item->filter); | |
1761 | list_del(&filter_item->list); | |
1762 | kfree(filter_item); | |
1763 | } | |
fce29d15 | 1764 | return 0; |
0fc3ca9a | 1765 | fail: |
75b8e982 SR |
1766 | /* No call succeeded */ |
1767 | list_for_each_entry_safe(filter_item, tmp, &filter_list, list) { | |
1768 | list_del(&filter_item->list); | |
1769 | kfree(filter_item); | |
1770 | } | |
0fc3ca9a SR |
1771 | parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0); |
1772 | return -EINVAL; | |
75b8e982 SR |
1773 | fail_mem: |
1774 | /* If any call succeeded, we still need to sync */ | |
1775 | if (!fail) | |
1776 | synchronize_sched(); | |
1777 | list_for_each_entry_safe(filter_item, tmp, &filter_list, list) { | |
1778 | __free_filter(filter_item->filter); | |
1779 | list_del(&filter_item->list); | |
1780 | kfree(filter_item); | |
1781 | } | |
1782 | return -ENOMEM; | |
fce29d15 LZ |
1783 | } |
1784 | ||
8b372562 TZ |
1785 | int apply_event_filter(struct ftrace_event_call *call, char *filter_string) |
1786 | { | |
8b372562 | 1787 | struct filter_parse_state *ps; |
75b8e982 SR |
1788 | struct event_filter *filter; |
1789 | struct event_filter *tmp; | |
1790 | int err = 0; | |
8b372562 | 1791 | |
00e95830 | 1792 | mutex_lock(&event_mutex); |
8b372562 TZ |
1793 | |
1794 | if (!strcmp(strstrip(filter_string), "0")) { | |
75b8e982 SR |
1795 | filter_disable(call); |
1796 | filter = call->filter; | |
1797 | if (!filter) | |
1798 | goto out_unlock; | |
1799 | call->filter = NULL; | |
f76690af SR |
1800 | /* Make sure the filter is not being used */ |
1801 | synchronize_sched(); | |
75b8e982 | 1802 | __free_filter(filter); |
a66abe7f | 1803 | goto out_unlock; |
8b372562 TZ |
1804 | } |
1805 | ||
8cd995b6 | 1806 | err = -ENOMEM; |
8b372562 TZ |
1807 | ps = kzalloc(sizeof(*ps), GFP_KERNEL); |
1808 | if (!ps) | |
8cd995b6 | 1809 | goto out_unlock; |
8b372562 | 1810 | |
75b8e982 SR |
1811 | filter = __alloc_filter(); |
1812 | if (!filter) { | |
1813 | kfree(ps); | |
1814 | goto out_unlock; | |
1815 | } | |
1816 | ||
1817 | replace_filter_string(filter, filter_string); | |
8b372562 TZ |
1818 | |
1819 | parse_init(ps, filter_ops, filter_string); | |
1820 | err = filter_parse(ps); | |
1821 | if (err) { | |
75b8e982 | 1822 | append_filter_err(ps, filter); |
8b372562 TZ |
1823 | goto out; |
1824 | } | |
1825 | ||
75b8e982 SR |
1826 | err = replace_preds(call, filter, ps, filter_string, false); |
1827 | if (err) { | |
1828 | filter_disable(call); | |
1829 | append_filter_err(ps, filter); | |
1830 | } else | |
553552ce | 1831 | call->flags |= TRACE_EVENT_FL_FILTERED; |
8b372562 | 1832 | out: |
75b8e982 SR |
1833 | /* |
1834 | * Always swap the call filter with the new filter | |
1835 | * even if there was an error. If there was an error | |
1836 | * in the filter, we disable the filter and show the error | |
1837 | * string | |
1838 | */ | |
1839 | tmp = call->filter; | |
1840 | call->filter = filter; | |
1841 | if (tmp) { | |
1842 | /* Make sure the call is done with the filter */ | |
1843 | synchronize_sched(); | |
1844 | __free_filter(tmp); | |
1845 | } | |
8b372562 TZ |
1846 | filter_opstack_clear(ps); |
1847 | postfix_clear(ps); | |
1848 | kfree(ps); | |
8cd995b6 | 1849 | out_unlock: |
00e95830 | 1850 | mutex_unlock(&event_mutex); |
8b372562 TZ |
1851 | |
1852 | return err; | |
1853 | } | |
1854 | ||
1855 | int apply_subsystem_event_filter(struct event_subsystem *system, | |
1856 | char *filter_string) | |
1857 | { | |
8b372562 | 1858 | struct filter_parse_state *ps; |
75b8e982 SR |
1859 | struct event_filter *filter; |
1860 | int err = 0; | |
8b372562 | 1861 | |
00e95830 | 1862 | mutex_lock(&event_mutex); |
8b372562 | 1863 | |
e9dbfae5 SR |
1864 | /* Make sure the system still has events */ |
1865 | if (!system->nr_events) { | |
1866 | err = -ENODEV; | |
1867 | goto out_unlock; | |
1868 | } | |
1869 | ||
8b372562 | 1870 | if (!strcmp(strstrip(filter_string), "0")) { |
fce29d15 | 1871 | filter_free_subsystem_preds(system); |
8b372562 | 1872 | remove_filter_string(system->filter); |
75b8e982 SR |
1873 | filter = system->filter; |
1874 | system->filter = NULL; | |
1875 | /* Ensure all filters are no longer used */ | |
1876 | synchronize_sched(); | |
1877 | filter_free_subsystem_filters(system); | |
1878 | __free_filter(filter); | |
a66abe7f | 1879 | goto out_unlock; |
8b372562 TZ |
1880 | } |
1881 | ||
8cd995b6 | 1882 | err = -ENOMEM; |
8b372562 TZ |
1883 | ps = kzalloc(sizeof(*ps), GFP_KERNEL); |
1884 | if (!ps) | |
8cd995b6 | 1885 | goto out_unlock; |
8b372562 | 1886 | |
75b8e982 SR |
1887 | filter = __alloc_filter(); |
1888 | if (!filter) | |
1889 | goto out; | |
1890 | ||
1891 | replace_filter_string(filter, filter_string); | |
1892 | /* | |
1893 | * No event actually uses the system filter | |
1894 | * we can free it without synchronize_sched(). | |
1895 | */ | |
1896 | __free_filter(system->filter); | |
1897 | system->filter = filter; | |
8b372562 TZ |
1898 | |
1899 | parse_init(ps, filter_ops, filter_string); | |
1900 | err = filter_parse(ps); | |
1901 | if (err) { | |
1902 | append_filter_err(ps, system->filter); | |
1903 | goto out; | |
1904 | } | |
1905 | ||
fce29d15 LZ |
1906 | err = replace_system_preds(system, ps, filter_string); |
1907 | if (err) | |
8b372562 TZ |
1908 | append_filter_err(ps, system->filter); |
1909 | ||
1910 | out: | |
1911 | filter_opstack_clear(ps); | |
1912 | postfix_clear(ps); | |
1913 | kfree(ps); | |
8cd995b6 | 1914 | out_unlock: |
00e95830 | 1915 | mutex_unlock(&event_mutex); |
8b372562 TZ |
1916 | |
1917 | return err; | |
1918 | } | |
7ce7e424 | 1919 | |
07b139c8 | 1920 | #ifdef CONFIG_PERF_EVENTS |
6fb2915d LZ |
1921 | |
1922 | void ftrace_profile_free_filter(struct perf_event *event) | |
1923 | { | |
1924 | struct event_filter *filter = event->filter; | |
1925 | ||
1926 | event->filter = NULL; | |
c9c53ca0 | 1927 | __free_filter(filter); |
6fb2915d LZ |
1928 | } |
1929 | ||
1930 | int ftrace_profile_set_filter(struct perf_event *event, int event_id, | |
1931 | char *filter_str) | |
1932 | { | |
1933 | int err; | |
1934 | struct event_filter *filter; | |
1935 | struct filter_parse_state *ps; | |
1936 | struct ftrace_event_call *call = NULL; | |
1937 | ||
1938 | mutex_lock(&event_mutex); | |
1939 | ||
1940 | list_for_each_entry(call, &ftrace_events, list) { | |
32c0edae | 1941 | if (call->event.type == event_id) |
6fb2915d LZ |
1942 | break; |
1943 | } | |
a66abe7f IM |
1944 | |
1945 | err = -EINVAL; | |
d9f599e1 | 1946 | if (&call->list == &ftrace_events) |
a66abe7f | 1947 | goto out_unlock; |
6fb2915d | 1948 | |
a66abe7f | 1949 | err = -EEXIST; |
6fb2915d | 1950 | if (event->filter) |
a66abe7f | 1951 | goto out_unlock; |
6fb2915d | 1952 | |
c9c53ca0 | 1953 | filter = __alloc_filter(); |
75b8e982 | 1954 | if (!filter) { |
a66abe7f IM |
1955 | err = PTR_ERR(filter); |
1956 | goto out_unlock; | |
1957 | } | |
6fb2915d LZ |
1958 | |
1959 | err = -ENOMEM; | |
1960 | ps = kzalloc(sizeof(*ps), GFP_KERNEL); | |
1961 | if (!ps) | |
c9c53ca0 | 1962 | goto free_filter; |
6fb2915d LZ |
1963 | |
1964 | parse_init(ps, filter_ops, filter_str); | |
1965 | err = filter_parse(ps); | |
1966 | if (err) | |
1967 | goto free_ps; | |
1968 | ||
1969 | err = replace_preds(call, filter, ps, filter_str, false); | |
1970 | if (!err) | |
1971 | event->filter = filter; | |
1972 | ||
1973 | free_ps: | |
1974 | filter_opstack_clear(ps); | |
1975 | postfix_clear(ps); | |
1976 | kfree(ps); | |
1977 | ||
c9c53ca0 | 1978 | free_filter: |
6fb2915d | 1979 | if (err) |
c9c53ca0 | 1980 | __free_filter(filter); |
6fb2915d | 1981 | |
a66abe7f | 1982 | out_unlock: |
6fb2915d LZ |
1983 | mutex_unlock(&event_mutex); |
1984 | ||
1985 | return err; | |
1986 | } | |
1987 | ||
07b139c8 | 1988 | #endif /* CONFIG_PERF_EVENTS */ |
6fb2915d | 1989 |