kernel/trace/trace_events_filter.c

   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
  21 #include <linux/module.h>
  22 #include <linux/ctype.h>
  23 #include <linux/mutex.h>
  24 #include <linux/perf_event.h>
  25 #include <linux/slab.h>
  26
  27 #include "trace.h"
  28 #include "trace_output.h"
  29
  30 #define DEFAULT_SYS_FILTER_MESSAGE                                      \
  31         "### global filter ###\n"                                       \
  32         "# Use this to set filters for multiple events.\n"              \
  33         "# Only events with the given fields will be affected.\n"       \
  34         "# If no events are modified, an error message will be displayed here"
  35
  36 enum filter_op_ids
  37 {
  38         OP_OR,
  39         OP_AND,
  40         OP_GLOB,
  41         OP_NE,
  42         OP_EQ,
  43         OP_LT,
  44         OP_LE,
  45         OP_GT,
  46         OP_GE,
  47         OP_BAND,
  48         OP_NOT,
  49         OP_NONE,
  50         OP_OPEN_PAREN,
  51 };
  52
  53 struct filter_op {
  54         int id;
  55         char *string;
  56         int precedence;
  57 };
  58
  59 /* Order must be the same as enum filter_op_ids above */
  60 static struct filter_op filter_ops[] = {
  61         { OP_OR,        "||",           1 },
  62         { OP_AND,       "&&",           2 },
  63         { OP_GLOB,      "~",            4 },
  64         { OP_NE,        "!=",           4 },
  65         { OP_EQ,        "==",           4 },
  66         { OP_LT,        "<",            5 },
  67         { OP_LE,        "<=",           5 },
  68         { OP_GT,        ">",            5 },
  69         { OP_GE,        ">=",           5 },
  70         { OP_BAND,      "&",            6 },
  71         { OP_NOT,       "!",            6 },
  72         { OP_NONE,      "OP_NONE",      0 },
  73         { OP_OPEN_PAREN, "(",           0 },
  74 };
  75
  76 enum {
  77         FILT_ERR_NONE,
  78         FILT_ERR_INVALID_OP,
  79         FILT_ERR_UNBALANCED_PAREN,
  80         FILT_ERR_TOO_MANY_OPERANDS,
  81         FILT_ERR_OPERAND_TOO_LONG,
  82         FILT_ERR_FIELD_NOT_FOUND,
  83         FILT_ERR_ILLEGAL_FIELD_OP,
  84         FILT_ERR_ILLEGAL_INTVAL,
  85         FILT_ERR_BAD_SUBSYS_FILTER,
  86         FILT_ERR_TOO_MANY_PREDS,
  87         FILT_ERR_MISSING_FIELD,
  88         FILT_ERR_INVALID_FILTER,
  89         FILT_ERR_IP_FIELD_ONLY,
  90         FILT_ERR_ILLEGAL_NOT_OP,
  91 };
  92
  93 static char *err_text[] = {
  94         "No error",
  95         "Invalid operator",
  96         "Unbalanced parens",
  97         "Too many operands",
  98         "Operand too long",
  99         "Field not found",
 100         "Illegal operation for field type",
 101         "Illegal integer value",
 102         "Couldn't find or set field in one of a subsystem's events",
 103         "Too many terms in predicate expression",
 104         "Missing field name and/or value",
 105         "Meaningless filter expression",
 106         "Only 'ip' field is supported for function trace",
 107         "Illegal use of '!'",
 108 };
 109
 110 struct opstack_op {
 111         int op;
 112         struct list_head list;
 113 };
 114
 115 struct postfix_elt {
 116         int op;
 117         char *operand;
 118         struct list_head list;
 119 };
 120
 121 struct filter_parse_state {
 122         struct filter_op *ops;
 123         struct list_head opstack;
 124         struct list_head postfix;
 125         int lasterr;
 126         int lasterr_pos;
 127
 128         struct {
 129                 char *string;
 130                 unsigned int cnt;
 131                 unsigned int tail;
 132         } infix;
 133
 134         struct {
 135                 char string[MAX_FILTER_STR_VAL];
 136                 int pos;
 137                 unsigned int tail;
 138         } operand;
 139 };
 140
 141 struct pred_stack {
 142         struct filter_pred      **preds;
 143         int                     index;
 144 };
 145
 146 /* If not of not match is equal to not of not, then it is a match */
 147 #define DEFINE_COMPARISON_PRED(type)                                    \
 148 static int filter_pred_##type(struct filter_pred *pred, void *event)    \
 149 {                                                                       \
 150         type *addr = (type *)(event + pred->offset);                    \
 151         type val = (type)pred->val;                                     \
 152         int match = 0;                                                  \
 153                                                                         \
 154         switch (pred->op) {                                             \
 155         case OP_LT:                                                     \
 156                 match = (*addr < val);                                  \
 157                 break;                                                  \
 158         case OP_LE:                                                     \
 159                 match = (*addr <= val);                                 \
 160                 break;                                                  \
 161         case OP_GT:                                                     \
 162                 match = (*addr > val);                                  \
 163                 break;                                                  \
 164         case OP_GE:                                                     \
 165                 match = (*addr >= val);                                 \
 166                 break;                                                  \
 167         case OP_BAND:                                                   \
 168                 match = (*addr & val);                                  \
 169                 break;                                                  \
 170         default:                                                        \
 171                 break;                                                  \
 172         }                                                               \
 173                                                                         \
 174         return !!match == !pred->not;                                   \
 175 }
 176
 177 #define DEFINE_EQUALITY_PRED(size)                                      \
 178 static int filter_pred_##size(struct filter_pred *pred, void *event)    \
 179 {                                                                       \
 180         u##size *addr = (u##size *)(event + pred->offset);              \
 181         u##size val = (u##size)pred->val;                               \
 182         int match;                                                      \
 183                                                                         \
 184         match = (val == *addr) ^ pred->not;                             \
 185                                                                         \
 186         return match;                                                   \
 187 }
 188
 189 DEFINE_COMPARISON_PRED(s64);
 190 DEFINE_COMPARISON_PRED(u64);
 191 DEFINE_COMPARISON_PRED(s32);
 192 DEFINE_COMPARISON_PRED(u32);
 193 DEFINE_COMPARISON_PRED(s16);
 194 DEFINE_COMPARISON_PRED(u16);
 195 DEFINE_COMPARISON_PRED(s8);
 196 DEFINE_COMPARISON_PRED(u8);
 197
 198 DEFINE_EQUALITY_PRED(64);
 199 DEFINE_EQUALITY_PRED(32);
 200 DEFINE_EQUALITY_PRED(16);
 201 DEFINE_EQUALITY_PRED(8);
 202
 203 /* Filter predicate for fixed sized arrays of characters */
 204 static int filter_pred_string(struct filter_pred *pred, void *event)
 205 {
 206         char *addr = (char *)(event + pred->offset);
 207         int cmp, match;
 208
 209         cmp = pred->regex.match(addr, &pred->regex, pred->regex.field_len);
 210
 211         match = cmp ^ pred->not;
 212
 213         return match;
 214 }
 215
 216 /* Filter predicate for char * pointers */
 217 static int filter_pred_pchar(struct filter_pred *pred, void *event)
 218 {
 219         char **addr = (char **)(event + pred->offset);
 220         int cmp, match;
 221         int len = strlen(*addr) + 1;    /* including tailing '\0' */
 222
 223         cmp = pred->regex.match(*addr, &pred->regex, len);
 224
 225         match = cmp ^ pred->not;
 226
 227         return match;
 228 }
 229
 230 /*
 231  * Filter predicate for dynamic sized arrays of characters.
 232  * These are implemented through a list of strings at the end
 233  * of the entry.
 234  * Also each of these strings have a field in the entry which
 235  * contains its offset from the beginning of the entry.
 236  * We have then first to get this field, dereference it
 237  * and add it to the address of the entry, and at last we have
 238  * the address of the string.
 239  */
 240 static int filter_pred_strloc(struct filter_pred *pred, void *event)
 241 {
 242         u32 str_item = *(u32 *)(event + pred->offset);
 243         int str_loc = str_item & 0xffff;
 244         int str_len = str_item >> 16;
 245         char *addr = (char *)(event + str_loc);
 246         int cmp, match;
 247
 248         cmp = pred->regex.match(addr, &pred->regex, str_len);
 249
 250         match = cmp ^ pred->not;
 251
 252         return match;
 253 }
 254
 255 static int filter_pred_none(struct filter_pred *pred, void *event)
 256 {
 257         return 0;
 258 }
 259
 260 /*
 261  * regex_match_foo - Basic regex callbacks
 262  *
 263  * @str: the string to be searched
 264  * @r:   the regex structure containing the pattern string
 265  * @len: the length of the string to be searched (including '\0')
 266  *
 267  * Note:
 268  * - @str might not be NULL-terminated if it's of type DYN_STRING
 269  *   or STATIC_STRING
 270  */
 271
 272 static int regex_match_full(char *str, struct regex *r, int len)
 273 {
 274         if (strncmp(str, r->pattern, len) == 0)
 275                 return 1;
 276         return 0;
 277 }
 278
 279 static int regex_match_front(char *str, struct regex *r, int len)
 280 {
 281         if (strncmp(str, r->pattern, r->len) == 0)
 282                 return 1;
 283         return 0;
 284 }
 285
 286 static int regex_match_middle(char *str, struct regex *r, int len)
 287 {
 288         if (strnstr(str, r->pattern, len))
 289                 return 1;
 290         return 0;
 291 }
 292
 293 static int regex_match_end(char *str, struct regex *r, int len)
 294 {
 295         int strlen = len - 1;
 296
 297         if (strlen >= r->len &&
 298             memcmp(str + strlen - r->len, r->pattern, r->len) == 0)
 299                 return 1;
 300         return 0;
 301 }
 302
 303 /**
 304  * filter_parse_regex - parse a basic regex
 305  * @buff:   the raw regex
 306  * @len:    length of the regex
 307  * @search: will point to the beginning of the string to compare
 308  * @not:    tell whether the match will have to be inverted
 309  *
 310  * This passes in a buffer containing a regex and this function will
 311  * set search to point to the search part of the buffer and
 312  * return the type of search it is (see enum above).
 313  * This does modify buff.
 314  *
 315  * Returns enum type.
 316  *  search returns the pointer to use for comparison.
 317  *  not returns 1 if buff started with a '!'
 318  *     0 otherwise.
 319  */
 320 enum regex_type filter_parse_regex(char *buff, int len, char **search, int *not)
 321 {
 322         int type = MATCH_FULL;
 323         int i;
 324
 325         if (buff[0] == '!') {
 326                 *not = 1;
 327                 buff++;
 328                 len--;
 329         } else
 330                 *not = 0;
 331
 332         *search = buff;
 333
 334         for (i = 0; i < len; i++) {
 335                 if (buff[i] == '*') {
 336                         if (!i) {
 337                                 *search = buff + 1;
 338                                 type = MATCH_END_ONLY;
 339                         } else {
 340                                 if (type == MATCH_END_ONLY)
 341                                         type = MATCH_MIDDLE_ONLY;
 342                                 else
 343                                         type = MATCH_FRONT_ONLY;
 344                                 buff[i] = 0;
 345                                 break;
 346                         }
 347                 }
 348         }
 349
 350         return type;
 351 }
 352
 353 static void filter_build_regex(struct filter_pred *pred)
 354 {
 355         struct regex *r = &pred->regex;
 356         char *search;
 357         enum regex_type type = MATCH_FULL;
 358         int not = 0;
 359
 360         if (pred->op == OP_GLOB) {
 361                 type = filter_parse_regex(r->pattern, r->len, &search, &not);
 362                 r->len = strlen(search);
 363                 memmove(r->pattern, search, r->len+1);
 364         }
 365
 366         switch (type) {
 367         case MATCH_FULL:
 368                 r->match = regex_match_full;
 369                 break;
 370         case MATCH_FRONT_ONLY:
 371                 r->match = regex_match_front;
 372                 break;
 373         case MATCH_MIDDLE_ONLY:
 374                 r->match = regex_match_middle;
 375                 break;
 376         case MATCH_END_ONLY:
 377                 r->match = regex_match_end;
 378                 break;
 379         }
 380
 381         pred->not ^= not;
 382 }
 383
 384 enum move_type {
 385         MOVE_DOWN,
 386         MOVE_UP_FROM_LEFT,
 387         MOVE_UP_FROM_RIGHT
 388 };
 389
 390 static struct filter_pred *
 391 get_pred_parent(struct filter_pred *pred, struct filter_pred *preds,
 392                 int index, enum move_type *move)
 393 {
 394         if (pred->parent & FILTER_PRED_IS_RIGHT)
 395                 *move = MOVE_UP_FROM_RIGHT;
 396         else
 397                 *move = MOVE_UP_FROM_LEFT;
 398         pred = &preds[pred->parent & ~FILTER_PRED_IS_RIGHT];
 399
 400         return pred;
 401 }
 402
 403 enum walk_return {
 404         WALK_PRED_ABORT,
 405         WALK_PRED_PARENT,
 406         WALK_PRED_DEFAULT,
 407 };
 408
 409 typedef int (*filter_pred_walkcb_t) (enum move_type move,
 410                                      struct filter_pred *pred,
 411                                      int *err, void *data);
 412
 413 static int walk_pred_tree(struct filter_pred *preds,
 414                           struct filter_pred *root,
 415                           filter_pred_walkcb_t cb, void *data)
 416 {
 417         struct filter_pred *pred = root;
 418         enum move_type move = MOVE_DOWN;
 419         int done = 0;
 420
 421         if  (!preds)
 422                 return -EINVAL;
 423
 424         do {
 425                 int err = 0, ret;
 426
 427                 ret = cb(move, pred, &err, data);
 428                 if (ret == WALK_PRED_ABORT)
 429                         return err;
 430                 if (ret == WALK_PRED_PARENT)
 431                         goto get_parent;
 432
 433                 switch (move) {
 434                 case MOVE_DOWN:
 435                         if (pred->left != FILTER_PRED_INVALID) {
 436                                 pred = &preds[pred->left];
 437                                 continue;
 438                         }
 439                         goto get_parent;
 440                 case MOVE_UP_FROM_LEFT:
 441                         pred = &preds[pred->right];
 442                         move = MOVE_DOWN;
 443                         continue;
 444                 case MOVE_UP_FROM_RIGHT:
 445  get_parent:
 446                         if (pred == root)
 447                                 break;
 448                         pred = get_pred_parent(pred, preds,
 449                                                pred->parent,
 450                                                &move);
 451                         continue;
 452                 }
 453                 done = 1;
 454         } while (!done);
 455
 456         /* We are fine. */
 457         return 0;
 458 }
 459
 460 /*
 461  * A series of AND or ORs where found together. Instead of
 462  * climbing up and down the tree branches, an array of the
 463  * ops were made in order of checks. We can just move across
 464  * the array and short circuit if needed.
 465  */
 466 static int process_ops(struct filter_pred *preds,
 467                        struct filter_pred *op, void *rec)
 468 {
 469         struct filter_pred *pred;
 470         int match = 0;
 471         int type;
 472         int i;
 473
 474         /*
 475          * Micro-optimization: We set type to true if op
 476          * is an OR and false otherwise (AND). Then we
 477          * just need to test if the match is equal to
 478          * the type, and if it is, we can short circuit the
 479          * rest of the checks:
 480          *
 481          * if ((match && op->op == OP_OR) ||
 482          *     (!match && op->op == OP_AND))
 483          *        return match;
 484          */
 485         type = op->op == OP_OR;
 486
 487         for (i = 0; i < op->val; i++) {
 488                 pred = &preds[op->ops[i]];
 489                 if (!WARN_ON_ONCE(!pred->fn))
 490                         match = pred->fn(pred, rec);
 491                 if (!!match == type)
 492                         break;
 493         }
 494         /* If not of not match is equal to not of not, then it is a match */
 495         return !!match == !op->not;
 496 }
 497
 498 struct filter_match_preds_data {
 499         struct filter_pred *preds;
 500         int match;
 501         void *rec;
 502 };
 503
 504 static int filter_match_preds_cb(enum move_type move, struct filter_pred *pred,
 505                                  int *err, void *data)
 506 {
 507         struct filter_match_preds_data *d = data;
 508
 509         *err = 0;
 510         switch (move) {
 511         case MOVE_DOWN:
 512                 /* only AND and OR have children */
 513                 if (pred->left != FILTER_PRED_INVALID) {
 514                         /* If ops is set, then it was folded. */
 515                         if (!pred->ops)
 516                                 return WALK_PRED_DEFAULT;
 517                         /* We can treat folded ops as a leaf node */
 518                         d->match = process_ops(d->preds, pred, d->rec);
 519                 } else {
 520                         if (!WARN_ON_ONCE(!pred->fn))
 521                                 d->match = pred->fn(pred, d->rec);
 522                 }
 523
 524                 return WALK_PRED_PARENT;
 525         case MOVE_UP_FROM_LEFT:
 526                 /*
 527                  * Check for short circuits.
 528                  *
 529                  * Optimization: !!match == (pred->op == OP_OR)
 530                  *   is the same as:
 531                  * if ((match && pred->op == OP_OR) ||
 532                  *     (!match && pred->op == OP_AND))
 533                  */
 534                 if (!!d->match == (pred->op == OP_OR))
 535                         return WALK_PRED_PARENT;
 536                 break;
 537         case MOVE_UP_FROM_RIGHT:
 538                 break;
 539         }
 540
 541         return WALK_PRED_DEFAULT;
 542 }
 543
 544 /* return 1 if event matches, 0 otherwise (discard) */
 545 int filter_match_preds(struct event_filter *filter, void *rec)
 546 {
 547         struct filter_pred *preds;
 548         struct filter_pred *root;
 549         struct filter_match_preds_data data = {
 550                 /* match is currently meaningless */
 551                 .match = -1,
 552                 .rec   = rec,
 553         };
 554         int n_preds, ret;
 555
 556         /* no filter is considered a match */
 557         if (!filter)
 558                 return 1;
 559
 560         n_preds = filter->n_preds;
 561         if (!n_preds)
 562                 return 1;
 563
 564         /*
 565          * n_preds, root and filter->preds are protect with preemption disabled.
 566          */
 567         root = rcu_dereference_sched(filter->root);
 568         if (!root)
 569                 return 1;
 570
 571         data.preds = preds = rcu_dereference_sched(filter->preds);
 572         ret = walk_pred_tree(preds, root, filter_match_preds_cb, &data);
 573         WARN_ON(ret);
 574         return data.match;
 575 }
 576 EXPORT_SYMBOL_GPL(filter_match_preds);
 577
 578 static void parse_error(struct filter_parse_state *ps, int err, int pos)
 579 {
 580         ps->lasterr = err;
 581         ps->lasterr_pos = pos;
 582 }
 583
 584 static void remove_filter_string(struct event_filter *filter)
 585 {
 586         if (!filter)
 587                 return;
 588
 589         kfree(filter->filter_string);
 590         filter->filter_string = NULL;
 591 }
 592
 593 static int replace_filter_string(struct event_filter *filter,
 594                                  char *filter_string)
 595 {
 596         kfree(filter->filter_string);
 597         filter->filter_string = kstrdup(filter_string, GFP_KERNEL);
 598         if (!filter->filter_string)
 599                 return -ENOMEM;
 600
 601         return 0;
 602 }
 603
 604 static int append_filter_string(struct event_filter *filter,
 605                                 char *string)
 606 {
 607         int newlen;
 608         char *new_filter_string;
 609
 610         BUG_ON(!filter->filter_string);
 611         newlen = strlen(filter->filter_string) + strlen(string) + 1;
 612         new_filter_string = kmalloc(newlen, GFP_KERNEL);
 613         if (!new_filter_string)
 614                 return -ENOMEM;
 615
 616         strcpy(new_filter_string, filter->filter_string);
 617         strcat(new_filter_string, string);
 618         kfree(filter->filter_string);
 619         filter->filter_string = new_filter_string;
 620
 621         return 0;
 622 }
 623
 624 static void append_filter_err(struct filter_parse_state *ps,
 625                               struct event_filter *filter)
 626 {
 627         int pos = ps->lasterr_pos;
 628         char *buf, *pbuf;
 629
 630         buf = (char *)__get_free_page(GFP_TEMPORARY);
 631         if (!buf)
 632                 return;
 633
 634         append_filter_string(filter, "\n");
 635         memset(buf, ' ', PAGE_SIZE);
 636         if (pos > PAGE_SIZE - 128)
 637                 pos = 0;
 638         buf[pos] = '^';
 639         pbuf = &buf[pos] + 1;
 640
 641         sprintf(pbuf, "\nparse_error: %s\n", err_text[ps->lasterr]);
 642         append_filter_string(filter, buf);
 643         free_page((unsigned long) buf);
 644 }
 645
 646 static inline struct event_filter *event_filter(struct ftrace_event_file *file)
 647 {
 648         if (file->event_call->flags & TRACE_EVENT_FL_USE_CALL_FILTER)
 649                 return file->event_call->filter;
 650         else
 651                 return file->filter;
 652 }
 653
 654 /* caller must hold event_mutex */
 655 void print_event_filter(struct ftrace_event_file *file, struct trace_seq *s)
 656 {
 657         struct event_filter *filter = event_filter(file);
 658
 659         if (filter && filter->filter_string)
 660                 trace_seq_printf(s, "%s\n", filter->filter_string);
 661         else
 662                 trace_seq_puts(s, "none\n");
 663 }
 664
 665 void print_subsystem_event_filter(struct event_subsystem *system,
 666                                   struct trace_seq *s)
 667 {
 668         struct event_filter *filter;
 669
 670         mutex_lock(&event_mutex);
 671         filter = system->filter;
 672         if (filter && filter->filter_string)
 673                 trace_seq_printf(s, "%s\n", filter->filter_string);
 674         else
 675                 trace_seq_puts(s, DEFAULT_SYS_FILTER_MESSAGE "\n");
 676         mutex_unlock(&event_mutex);
 677 }
 678
 679 static int __alloc_pred_stack(struct pred_stack *stack, int n_preds)
 680 {
 681         stack->preds = kcalloc(n_preds + 1, sizeof(*stack->preds), GFP_KERNEL);
 682         if (!stack->preds)
 683                 return -ENOMEM;
 684         stack->index = n_preds;
 685         return 0;
 686 }
 687
 688 static void __free_pred_stack(struct pred_stack *stack)
 689 {
 690         kfree(stack->preds);
 691         stack->index = 0;
 692 }
 693
 694 static int __push_pred_stack(struct pred_stack *stack,
 695                              struct filter_pred *pred)
 696 {
 697         int index = stack->index;
 698
 699         if (WARN_ON(index == 0))
 700                 return -ENOSPC;
 701
 702         stack->preds[--index] = pred;
 703         stack->index = index;
 704         return 0;
 705 }
 706
 707 static struct filter_pred *
 708 __pop_pred_stack(struct pred_stack *stack)
 709 {
 710         struct filter_pred *pred;
 711         int index = stack->index;
 712
 713         pred = stack->preds[index++];
 714         if (!pred)
 715                 return NULL;
 716
 717         stack->index = index;
 718         return pred;
 719 }
 720
 721 static int filter_set_pred(struct event_filter *filter,
 722                            int idx,
 723                            struct pred_stack *stack,
 724                            struct filter_pred *src)
 725 {
 726         struct filter_pred *dest = &filter->preds[idx];
 727         struct filter_pred *left;
 728         struct filter_pred *right;
 729
 730         *dest = *src;
 731         dest->index = idx;
 732
 733         if (dest->op == OP_OR || dest->op == OP_AND) {
 734                 right = __pop_pred_stack(stack);
 735                 left = __pop_pred_stack(stack);
 736                 if (!left || !right)
 737                         return -EINVAL;
 738                 /*
 739                  * If both children can be folded
 740                  * and they are the same op as this op or a leaf,
 741                  * then this op can be folded.
 742                  */
 743                 if (left->index & FILTER_PRED_FOLD &&
 744                     ((left->op == dest->op && !left->not) ||
 745                      left->left == FILTER_PRED_INVALID) &&
 746                     right->index & FILTER_PRED_FOLD &&
 747                     ((right->op == dest->op && !right->not) ||
 748                      right->left == FILTER_PRED_INVALID))
 749                         dest->index |= FILTER_PRED_FOLD;
 750
 751                 dest->left = left->index & ~FILTER_PRED_FOLD;
 752                 dest->right = right->index & ~FILTER_PRED_FOLD;
 753                 left->parent = dest->index & ~FILTER_PRED_FOLD;
 754                 right->parent = dest->index | FILTER_PRED_IS_RIGHT;
 755         } else {
 756                 /*
 757                  * Make dest->left invalid to be used as a quick
 758                  * way to know this is a leaf node.
 759                  */
 760                 dest->left = FILTER_PRED_INVALID;
 761
 762                 /* All leafs allow folding the parent ops. */
 763                 dest->index |= FILTER_PRED_FOLD;
 764         }
 765
 766         return __push_pred_stack(stack, dest);
 767 }
 768
 769 static void __free_preds(struct event_filter *filter)
 770 {
 771         int i;
 772
 773         if (filter->preds) {
 774                 for (i = 0; i < filter->n_preds; i++)
 775                         kfree(filter->preds[i].ops);
 776                 kfree(filter->preds);
 777                 filter->preds = NULL;
 778         }
 779         filter->a_preds = 0;
 780         filter->n_preds = 0;
 781 }
 782
 783 static void filter_disable(struct ftrace_event_file *file)
 784 {
 785         struct ftrace_event_call *call = file->event_call;
 786
 787         if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER)
 788                 call->flags &= ~TRACE_EVENT_FL_FILTERED;
 789         else
 790                 file->flags &= ~FTRACE_EVENT_FL_FILTERED;
 791 }
 792
 793 static void __free_filter(struct event_filter *filter)
 794 {
 795         if (!filter)
 796                 return;
 797
 798         __free_preds(filter);
 799         kfree(filter->filter_string);
 800         kfree(filter);
 801 }
 802
 803 void free_event_filter(struct event_filter *filter)
 804 {
 805         __free_filter(filter);
 806 }
 807
 808 static struct event_filter *__alloc_filter(void)
 809 {
 810         struct event_filter *filter;
 811
 812         filter = kzalloc(sizeof(*filter), GFP_KERNEL);
 813         return filter;
 814 }
 815
 816 static int __alloc_preds(struct event_filter *filter, int n_preds)
 817 {
 818         struct filter_pred *pred;
 819         int i;
 820
 821         if (filter->preds)
 822                 __free_preds(filter);
 823
 824         filter->preds = kcalloc(n_preds, sizeof(*filter->preds), GFP_KERNEL);
 825
 826         if (!filter->preds)
 827                 return -ENOMEM;
 828
 829         filter->a_preds = n_preds;
 830         filter->n_preds = 0;
 831
 832         for (i = 0; i < n_preds; i++) {
 833                 pred = &filter->preds[i];
 834                 pred->fn = filter_pred_none;
 835         }
 836
 837         return 0;
 838 }
 839
 840 static inline void __remove_filter(struct ftrace_event_file *file)
 841 {
 842         struct ftrace_event_call *call = file->event_call;
 843
 844         filter_disable(file);
 845         if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER)
 846                 remove_filter_string(call->filter);
 847         else
 848                 remove_filter_string(file->filter);
 849 }
 850
 851 static void filter_free_subsystem_preds(struct ftrace_subsystem_dir *dir,
 852                                         struct trace_array *tr)
 853 {
 854         struct ftrace_event_file *file;
 855
 856         list_for_each_entry(file, &tr->events, list) {
 857                 if (file->system != dir)
 858                         continue;
 859                 __remove_filter(file);
 860         }
 861 }
 862
 863 static inline void __free_subsystem_filter(struct ftrace_event_file *file)
 864 {
 865         struct ftrace_event_call *call = file->event_call;
 866
 867         if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) {
 868                 __free_filter(call->filter);
 869                 call->filter = NULL;
 870         } else {
 871                 __free_filter(file->filter);
 872                 file->filter = NULL;
 873         }
 874 }
 875
 876 static void filter_free_subsystem_filters(struct ftrace_subsystem_dir *dir,
 877                                           struct trace_array *tr)
 878 {
 879         struct ftrace_event_file *file;
 880
 881         list_for_each_entry(file, &tr->events, list) {
 882                 if (file->system != dir)
 883                         continue;
 884                 __free_subsystem_filter(file);
 885         }
 886 }
 887
 888 static int filter_add_pred(struct filter_parse_state *ps,
 889                            struct event_filter *filter,
 890                            struct filter_pred *pred,
 891                            struct pred_stack *stack)
 892 {
 893         int err;
 894
 895         if (WARN_ON(filter->n_preds == filter->a_preds)) {
 896                 parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
 897                 return -ENOSPC;
 898         }
 899
 900         err = filter_set_pred(filter, filter->n_preds, stack, pred);
 901         if (err)
 902                 return err;
 903
 904         filter->n_preds++;
 905
 906         return 0;
 907 }
 908
 909 int filter_assign_type(const char *type)
 910 {
 911         if (strstr(type, "__data_loc") && strstr(type, "char"))
 912                 return FILTER_DYN_STRING;
 913
 914         if (strchr(type, '[') && strstr(type, "char"))
 915                 return FILTER_STATIC_STRING;
 916
 917         return FILTER_OTHER;
 918 }
 919
 920 static bool is_function_field(struct ftrace_event_field *field)
 921 {
 922         return field->filter_type == FILTER_TRACE_FN;
 923 }
 924
 925 static bool is_string_field(struct ftrace_event_field *field)
 926 {
 927         return field->filter_type == FILTER_DYN_STRING ||
 928                field->filter_type == FILTER_STATIC_STRING ||
 929                field->filter_type == FILTER_PTR_STRING;
 930 }
 931
 932 static int is_legal_op(struct ftrace_event_field *field, int op)
 933 {
 934         if (is_string_field(field) &&
 935             (op != OP_EQ && op != OP_NE && op != OP_GLOB))
 936                 return 0;
 937         if (!is_string_field(field) && op == OP_GLOB)
 938                 return 0;
 939
 940         return 1;
 941 }
 942
 943 static filter_pred_fn_t select_comparison_fn(int op, int field_size,
 944                                              int field_is_signed)
 945 {
 946         filter_pred_fn_t fn = NULL;
 947
 948         switch (field_size) {
 949         case 8:
 950                 if (op == OP_EQ || op == OP_NE)
 951                         fn = filter_pred_64;
 952                 else if (field_is_signed)
 953                         fn = filter_pred_s64;
 954                 else
 955                         fn = filter_pred_u64;
 956                 break;
 957         case 4:
 958                 if (op == OP_EQ || op == OP_NE)
 959                         fn = filter_pred_32;
 960                 else if (field_is_signed)
 961                         fn = filter_pred_s32;
 962                 else
 963                         fn = filter_pred_u32;
 964                 break;
 965         case 2:
 966                 if (op == OP_EQ || op == OP_NE)
 967                         fn = filter_pred_16;
 968                 else if (field_is_signed)
 969                         fn = filter_pred_s16;
 970                 else
 971                         fn = filter_pred_u16;
 972                 break;
 973         case 1:
 974                 if (op == OP_EQ || op == OP_NE)
 975                         fn = filter_pred_8;
 976                 else if (field_is_signed)
 977                         fn = filter_pred_s8;
 978                 else
 979                         fn = filter_pred_u8;
 980                 break;
 981         }
 982
 983         return fn;
 984 }
 985
 986 static int init_pred(struct filter_parse_state *ps,
 987                      struct ftrace_event_field *field,
 988                      struct filter_pred *pred)
 989
 990 {
 991         filter_pred_fn_t fn = filter_pred_none;
 992         unsigned long long val;
 993         int ret;
 994
 995         pred->offset = field->offset;
 996
 997         if (!is_legal_op(field, pred->op)) {
 998                 parse_error(ps, FILT_ERR_ILLEGAL_FIELD_OP, 0);
 999                 return -EINVAL;
1000         }
1001
1002         if (is_string_field(field)) {
1003                 filter_build_regex(pred);
1004
1005                 if (field->filter_type == FILTER_STATIC_STRING) {
1006                         fn = filter_pred_string;
1007                         pred->regex.field_len = field->size;
1008                 } else if (field->filter_type == FILTER_DYN_STRING)
1009                         fn = filter_pred_strloc;
1010                 else
1011                         fn = filter_pred_pchar;
1012         } else if (is_function_field(field)) {
1013                 if (strcmp(field->name, "ip")) {
1014                         parse_error(ps, FILT_ERR_IP_FIELD_ONLY, 0);
1015                         return -EINVAL;
1016                 }
1017         } else {
1018                 if (field->is_signed)
1019                         ret = kstrtoll(pred->regex.pattern, 0, &val);
1020                 else
1021                         ret = kstrtoull(pred->regex.pattern, 0, &val);
1022                 if (ret) {
1023                         parse_error(ps, FILT_ERR_ILLEGAL_INTVAL, 0);
1024                         return -EINVAL;
1025                 }
1026                 pred->val = val;
1027
1028                 fn = select_comparison_fn(pred->op, field->size,
1029                                           field->is_signed);
1030                 if (!fn) {
1031                         parse_error(ps, FILT_ERR_INVALID_OP, 0);
1032                         return -EINVAL;
1033                 }
1034         }
1035
1036         if (pred->op == OP_NE)
1037                 pred->not ^= 1;
1038
1039         pred->fn = fn;
1040         return 0;
1041 }
1042
1043 static void parse_init(struct filter_parse_state *ps,
1044                        struct filter_op *ops,
1045                        char *infix_string)
1046 {
1047         memset(ps, '\0', sizeof(*ps));
1048
1049         ps->infix.string = infix_string;
1050         ps->infix.cnt = strlen(infix_string);
1051         ps->ops = ops;
1052
1053         INIT_LIST_HEAD(&ps->opstack);
1054         INIT_LIST_HEAD(&ps->postfix);
1055 }
1056
1057 static char infix_next(struct filter_parse_state *ps)
1058 {
1059         ps->infix.cnt--;
1060
1061         return ps->infix.string[ps->infix.tail++];
1062 }
1063
1064 static char infix_peek(struct filter_parse_state *ps)
1065 {
1066         if (ps->infix.tail == strlen(ps->infix.string))
1067                 return 0;
1068
1069         return ps->infix.string[ps->infix.tail];
1070 }
1071
1072 static void infix_advance(struct filter_parse_state *ps)
1073 {
1074         ps->infix.cnt--;
1075         ps->infix.tail++;
1076 }
1077
1078 static inline int is_precedence_lower(struct filter_parse_state *ps,
1079                                       int a, int b)
1080 {
1081         return ps->ops[a].precedence < ps->ops[b].precedence;
1082 }
1083
1084 static inline int is_op_char(struct filter_parse_state *ps, char c)
1085 {
1086         int i;
1087
1088         for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) {
1089                 if (ps->ops[i].string[0] == c)
1090                         return 1;
1091         }
1092
1093         return 0;
1094 }
1095
1096 static int infix_get_op(struct filter_parse_state *ps, char firstc)
1097 {
1098         char nextc = infix_peek(ps);
1099         char opstr[3];
1100         int i;
1101
1102         opstr[0] = firstc;
1103         opstr[1] = nextc;
1104         opstr[2] = '\0';
1105
1106         for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) {
1107                 if (!strcmp(opstr, ps->ops[i].string)) {
1108                         infix_advance(ps);
1109                         return ps->ops[i].id;
1110                 }
1111         }
1112
1113         opstr[1] = '\0';
1114
1115         for (i = 0; strcmp(ps->ops[i].string, "OP_NONE"); i++) {
1116                 if (!strcmp(opstr, ps->ops[i].string))
1117                         return ps->ops[i].id;
1118         }
1119
1120         return OP_NONE;
1121 }
1122
1123 static inline void clear_operand_string(struct filter_parse_state *ps)
1124 {
1125         memset(ps->operand.string, '\0', MAX_FILTER_STR_VAL);
1126         ps->operand.tail = 0;
1127 }
1128
1129 static inline int append_operand_char(struct filter_parse_state *ps, char c)
1130 {
1131         if (ps->operand.tail == MAX_FILTER_STR_VAL - 1)
1132                 return -EINVAL;
1133
1134         ps->operand.string[ps->operand.tail++] = c;
1135
1136         return 0;
1137 }
1138
1139 static int filter_opstack_push(struct filter_parse_state *ps, int op)
1140 {
1141         struct opstack_op *opstack_op;
1142
1143         opstack_op = kmalloc(sizeof(*opstack_op), GFP_KERNEL);
1144         if (!opstack_op)
1145                 return -ENOMEM;
1146
1147         opstack_op->op = op;
1148         list_add(&opstack_op->list, &ps->opstack);
1149
1150         return 0;
1151 }
1152
1153 static int filter_opstack_empty(struct filter_parse_state *ps)
1154 {
1155         return list_empty(&ps->opstack);
1156 }
1157
1158 static int filter_opstack_top(struct filter_parse_state *ps)
1159 {
1160         struct opstack_op *opstack_op;
1161
1162         if (filter_opstack_empty(ps))
1163                 return OP_NONE;
1164
1165         opstack_op = list_first_entry(&ps->opstack, struct opstack_op, list);
1166
1167         return opstack_op->op;
1168 }
1169
1170 static int filter_opstack_pop(struct filter_parse_state *ps)
1171 {
1172         struct opstack_op *opstack_op;
1173         int op;
1174
1175         if (filter_opstack_empty(ps))
1176                 return OP_NONE;
1177
1178         opstack_op = list_first_entry(&ps->opstack, struct opstack_op, list);
1179         op = opstack_op->op;
1180         list_del(&opstack_op->list);
1181
1182         kfree(opstack_op);
1183
1184         return op;
1185 }
1186
1187 static void filter_opstack_clear(struct filter_parse_state *ps)
1188 {
1189         while (!filter_opstack_empty(ps))
1190                 filter_opstack_pop(ps);
1191 }
1192
1193 static char *curr_operand(struct filter_parse_state *ps)
1194 {
1195         return ps->operand.string;
1196 }
1197
1198 static int postfix_append_operand(struct filter_parse_state *ps, char *operand)
1199 {
1200         struct postfix_elt *elt;
1201
1202         elt = kmalloc(sizeof(*elt), GFP_KERNEL);
1203         if (!elt)
1204                 return -ENOMEM;
1205
1206         elt->op = OP_NONE;
1207         elt->operand = kstrdup(operand, GFP_KERNEL);
1208         if (!elt->operand) {
1209                 kfree(elt);
1210                 return -ENOMEM;
1211         }
1212
1213         list_add_tail(&elt->list, &ps->postfix);
1214
1215         return 0;
1216 }
1217
1218 static int postfix_append_op(struct filter_parse_state *ps, int op)
1219 {
1220         struct postfix_elt *elt;
1221
1222         elt = kmalloc(sizeof(*elt), GFP_KERNEL);
1223         if (!elt)
1224                 return -ENOMEM;
1225
1226         elt->op = op;
1227         elt->operand = NULL;
1228
1229         list_add_tail(&elt->list, &ps->postfix);
1230
1231         return 0;
1232 }
1233
1234 static void postfix_clear(struct filter_parse_state *ps)
1235 {
1236         struct postfix_elt *elt;
1237
1238         while (!list_empty(&ps->postfix)) {
1239                 elt = list_first_entry(&ps->postfix, struct postfix_elt, list);
1240                 list_del(&elt->list);
1241                 kfree(elt->operand);
1242                 kfree(elt);
1243         }
1244 }
1245
1246 static int filter_parse(struct filter_parse_state *ps)
1247 {
1248         int in_string = 0;
1249         int op, top_op;
1250         char ch;
1251
1252         while ((ch = infix_next(ps))) {
1253                 if (ch == '"') {
1254                         in_string ^= 1;
1255                         continue;
1256                 }
1257
1258                 if (in_string)
1259                         goto parse_operand;
1260
1261                 if (isspace(ch))
1262                         continue;
1263
1264                 if (is_op_char(ps, ch)) {
1265                         op = infix_get_op(ps, ch);
1266                         if (op == OP_NONE) {
1267                                 parse_error(ps, FILT_ERR_INVALID_OP, 0);
1268                                 return -EINVAL;
1269                         }
1270
1271                         if (strlen(curr_operand(ps))) {
1272                                 postfix_append_operand(ps, curr_operand(ps));
1273                                 clear_operand_string(ps);
1274                         }
1275
1276                         while (!filter_opstack_empty(ps)) {
1277                                 top_op = filter_opstack_top(ps);
1278                                 if (!is_precedence_lower(ps, top_op, op)) {
1279                                         top_op = filter_opstack_pop(ps);
1280                                         postfix_append_op(ps, top_op);
1281                                         continue;
1282                                 }
1283                                 break;
1284                         }
1285
1286                         filter_opstack_push(ps, op);
1287                         continue;
1288                 }
1289
1290                 if (ch == '(') {
1291                         filter_opstack_push(ps, OP_OPEN_PAREN);
1292                         continue;
1293                 }
1294
1295                 if (ch == ')') {
1296                         if (strlen(curr_operand(ps))) {
1297                                 postfix_append_operand(ps, curr_operand(ps));
1298                                 clear_operand_string(ps);
1299                         }
1300
1301                         top_op = filter_opstack_pop(ps);
1302                         while (top_op != OP_NONE) {
1303                                 if (top_op == OP_OPEN_PAREN)
1304                                         break;
1305                                 postfix_append_op(ps, top_op);
1306                                 top_op = filter_opstack_pop(ps);
1307                         }
1308                         if (top_op == OP_NONE) {
1309                                 parse_error(ps, FILT_ERR_UNBALANCED_PAREN, 0);
1310                                 return -EINVAL;
1311                         }
1312                         continue;
1313                 }
1314 parse_operand:
1315                 if (append_operand_char(ps, ch)) {
1316                         parse_error(ps, FILT_ERR_OPERAND_TOO_LONG, 0);
1317                         return -EINVAL;
1318                 }
1319         }
1320
1321         if (strlen(curr_operand(ps)))
1322                 postfix_append_operand(ps, curr_operand(ps));
1323
1324         while (!filter_opstack_empty(ps)) {
1325                 top_op = filter_opstack_pop(ps);
1326                 if (top_op == OP_NONE)
1327                         break;
1328                 if (top_op == OP_OPEN_PAREN) {
1329                         parse_error(ps, FILT_ERR_UNBALANCED_PAREN, 0);
1330                         return -EINVAL;
1331                 }
1332                 postfix_append_op(ps, top_op);
1333         }
1334
1335         return 0;
1336 }
1337
1338 static struct filter_pred *create_pred(struct filter_parse_state *ps,
1339                                        struct ftrace_event_call *call,
1340                                        int op, char *operand1, char *operand2)
1341 {
1342         struct ftrace_event_field *field;
1343         static struct filter_pred pred;
1344
1345         memset(&pred, 0, sizeof(pred));
1346         pred.op = op;
1347
1348         if (op == OP_AND || op == OP_OR)
1349                 return &pred;
1350
1351         if (!operand1 || !operand2) {
1352                 parse_error(ps, FILT_ERR_MISSING_FIELD, 0);
1353                 return NULL;
1354         }
1355
1356         field = trace_find_event_field(call, operand1);
1357         if (!field) {
1358                 parse_error(ps, FILT_ERR_FIELD_NOT_FOUND, 0);
1359                 return NULL;
1360         }
1361
1362         strcpy(pred.regex.pattern, operand2);
1363         pred.regex.len = strlen(pred.regex.pattern);
1364         pred.field = field;
1365         return init_pred(ps, field, &pred) ? NULL : &pred;
1366 }
1367
1368 static int check_preds(struct filter_parse_state *ps)
1369 {
1370         int n_normal_preds = 0, n_logical_preds = 0;
1371         struct postfix_elt *elt;
1372
1373         list_for_each_entry(elt, &ps->postfix, list) {
1374                 if (elt->op == OP_NONE)
1375                         continue;
1376
1377                 if (elt->op == OP_AND || elt->op == OP_OR) {
1378                         n_logical_preds++;
1379                         continue;
1380                 }
1381                 n_normal_preds++;
1382         }
1383
1384         if (!n_normal_preds || n_logical_preds >= n_normal_preds) {
1385                 parse_error(ps, FILT_ERR_INVALID_FILTER, 0);
1386                 return -EINVAL;
1387         }
1388
1389         return 0;
1390 }
1391
1392 static int count_preds(struct filter_parse_state *ps)
1393 {
1394         struct postfix_elt *elt;
1395         int n_preds = 0;
1396
1397         list_for_each_entry(elt, &ps->postfix, list) {
1398                 if (elt->op == OP_NONE)
1399                         continue;
1400                 n_preds++;
1401         }
1402
1403         return n_preds;
1404 }
1405
1406 struct check_pred_data {
1407         int count;
1408         int max;
1409 };
1410
1411 static int check_pred_tree_cb(enum move_type move, struct filter_pred *pred,
1412                               int *err, void *data)
1413 {
1414         struct check_pred_data *d = data;
1415
1416         if (WARN_ON(d->count++ > d->max)) {
1417                 *err = -EINVAL;
1418                 return WALK_PRED_ABORT;
1419         }
1420         return WALK_PRED_DEFAULT;
1421 }
1422
1423 /*
1424  * The tree is walked at filtering of an event. If the tree is not correctly
1425  * built, it may cause an infinite loop. Check here that the tree does
1426  * indeed terminate.
1427  */
1428 static int check_pred_tree(struct event_filter *filter,
1429                            struct filter_pred *root)
1430 {
1431         struct check_pred_data data = {
1432                 /*
1433                  * The max that we can hit a node is three times.
1434                  * Once going down, once coming up from left, and
1435                  * once coming up from right. This is more than enough
1436                  * since leafs are only hit a single time.
1437                  */
1438                 .max   = 3 * filter->n_preds,
1439                 .count = 0,
1440         };
1441
1442         return walk_pred_tree(filter->preds, root,
1443                               check_pred_tree_cb, &data);
1444 }
1445
1446 static int count_leafs_cb(enum move_type move, struct filter_pred *pred,
1447                           int *err, void *data)
1448 {
1449         int *count = data;
1450
1451         if ((move == MOVE_DOWN) &&
1452             (pred->left == FILTER_PRED_INVALID))
1453                 (*count)++;
1454
1455         return WALK_PRED_DEFAULT;
1456 }
1457
1458 static int count_leafs(struct filter_pred *preds, struct filter_pred *root)
1459 {
1460         int count = 0, ret;
1461
1462         ret = walk_pred_tree(preds, root, count_leafs_cb, &count);
1463         WARN_ON(ret);
1464         return count;
1465 }
1466
1467 struct fold_pred_data {
1468         struct filter_pred *root;
1469         int count;
1470         int children;
1471 };
1472
1473 static int fold_pred_cb(enum move_type move, struct filter_pred *pred,
1474                         int *err, void *data)
1475 {
1476         struct fold_pred_data *d = data;
1477         struct filter_pred *root = d->root;
1478
1479         if (move != MOVE_DOWN)
1480                 return WALK_PRED_DEFAULT;
1481         if (pred->left != FILTER_PRED_INVALID)
1482                 return WALK_PRED_DEFAULT;
1483
1484         if (WARN_ON(d->count == d->children)) {
1485                 *err = -EINVAL;
1486                 return WALK_PRED_ABORT;
1487         }
1488
1489         pred->index &= ~FILTER_PRED_FOLD;
1490         root->ops[d->count++] = pred->index;
1491         return WALK_PRED_DEFAULT;
1492 }
1493
1494 static int fold_pred(struct filter_pred *preds, struct filter_pred *root)
1495 {
1496         struct fold_pred_data data = {
1497                 .root  = root,
1498                 .count = 0,
1499         };
1500         int children;
1501
1502         /* No need to keep the fold flag */
1503         root->index &= ~FILTER_PRED_FOLD;
1504
1505         /* If the root is a leaf then do nothing */
1506         if (root->left == FILTER_PRED_INVALID)
1507                 return 0;
1508
1509         /* count the children */
1510         children = count_leafs(preds, &preds[root->left]);
1511         children += count_leafs(preds, &preds[root->right]);
1512
1513         root->ops = kcalloc(children, sizeof(*root->ops), GFP_KERNEL);
1514         if (!root->ops)
1515                 return -ENOMEM;
1516
1517         root->val = children;
1518         data.children = children;
1519         return walk_pred_tree(preds, root, fold_pred_cb, &data);
1520 }
1521
1522 static int fold_pred_tree_cb(enum move_type move, struct filter_pred *pred,
1523                              int *err, void *data)
1524 {
1525         struct filter_pred *preds = data;
1526
1527         if (move != MOVE_DOWN)
1528                 return WALK_PRED_DEFAULT;
1529         if (!(pred->index & FILTER_PRED_FOLD))
1530                 return WALK_PRED_DEFAULT;
1531
1532         *err = fold_pred(preds, pred);
1533         if (*err)
1534                 return WALK_PRED_ABORT;
1535
1536         /* eveyrhing below is folded, continue with parent */
1537         return WALK_PRED_PARENT;
1538 }
1539
1540 /*
1541  * To optimize the processing of the ops, if we have several "ors" or
1542  * "ands" together, we can put them in an array and process them all
1543  * together speeding up the filter logic.
1544  */
1545 static int fold_pred_tree(struct event_filter *filter,
1546                            struct filter_pred *root)
1547 {
1548         return walk_pred_tree(filter->preds, root, fold_pred_tree_cb,
1549                               filter->preds);
1550 }
1551
1552 static int replace_preds(struct ftrace_event_call *call,
1553                          struct event_filter *filter,
1554                          struct filter_parse_state *ps,
1555                          bool dry_run)
1556 {
1557         char *operand1 = NULL, *operand2 = NULL;
1558         struct filter_pred *pred;
1559         struct filter_pred *root;
1560         struct postfix_elt *elt;
1561         struct pred_stack stack = { }; /* init to NULL */
1562         int err;
1563         int n_preds = 0;
1564
1565         n_preds = count_preds(ps);
1566         if (n_preds >= MAX_FILTER_PRED) {
1567                 parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
1568                 return -ENOSPC;
1569         }
1570
1571         err = check_preds(ps);
1572         if (err)
1573                 return err;
1574
1575         if (!dry_run) {
1576                 err = __alloc_pred_stack(&stack, n_preds);
1577                 if (err)
1578                         return err;
1579                 err = __alloc_preds(filter, n_preds);
1580                 if (err)
1581                         goto fail;
1582         }
1583
1584         n_preds = 0;
1585         list_for_each_entry(elt, &ps->postfix, list) {
1586                 if (elt->op == OP_NONE) {
1587                         if (!operand1)
1588                                 operand1 = elt->operand;
1589                         else if (!operand2)
1590                                 operand2 = elt->operand;
1591                         else {
1592                                 parse_error(ps, FILT_ERR_TOO_MANY_OPERANDS, 0);
1593                                 err = -EINVAL;
1594                                 goto fail;
1595                         }
1596                         continue;
1597                 }
1598
1599                 if (elt->op == OP_NOT) {
1600                         if (!n_preds || operand1 || operand2) {
1601                                 parse_error(ps, FILT_ERR_ILLEGAL_NOT_OP, 0);
1602                                 err = -EINVAL;
1603                                 goto fail;
1604                         }
1605                         if (!dry_run)
1606                                 filter->preds[n_preds - 1].not ^= 1;
1607                         continue;
1608                 }
1609
1610                 if (WARN_ON(n_preds++ == MAX_FILTER_PRED)) {
1611                         parse_error(ps, FILT_ERR_TOO_MANY_PREDS, 0);
1612                         err = -ENOSPC;
1613                         goto fail;
1614                 }
1615
1616                 pred = create_pred(ps, call, elt->op, operand1, operand2);
1617                 if (!pred) {
1618                         err = -EINVAL;
1619                         goto fail;
1620                 }
1621
1622                 if (!dry_run) {
1623                         err = filter_add_pred(ps, filter, pred, &stack);
1624                         if (err)
1625                                 goto fail;
1626                 }
1627
1628                 operand1 = operand2 = NULL;
1629         }
1630
1631         if (!dry_run) {
1632                 /* We should have one item left on the stack */
1633                 pred = __pop_pred_stack(&stack);
1634                 if (!pred)
1635                         return -EINVAL;
1636                 /* This item is where we start from in matching */
1637                 root = pred;
1638                 /* Make sure the stack is empty */
1639                 pred = __pop_pred_stack(&stack);
1640                 if (WARN_ON(pred)) {
1641                         err = -EINVAL;
1642                         filter->root = NULL;
1643                         goto fail;
1644                 }
1645                 err = check_pred_tree(filter, root);
1646                 if (err)
1647                         goto fail;
1648
1649                 /* Optimize the tree */
1650                 err = fold_pred_tree(filter, root);
1651                 if (err)
1652                         goto fail;
1653
1654                 /* We don't set root until we know it works */
1655                 barrier();
1656                 filter->root = root;
1657         }
1658
1659         err = 0;
1660 fail:
1661         __free_pred_stack(&stack);
1662         return err;
1663 }
1664
1665 static inline void event_set_filtered_flag(struct ftrace_event_file *file)
1666 {
1667         struct ftrace_event_call *call = file->event_call;
1668
1669         if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER)
1670                 call->flags |= TRACE_EVENT_FL_FILTERED;
1671         else
1672                 file->flags |= FTRACE_EVENT_FL_FILTERED;
1673 }
1674
1675 static inline void event_set_filter(struct ftrace_event_file *file,
1676                                     struct event_filter *filter)
1677 {
1678         struct ftrace_event_call *call = file->event_call;
1679
1680         if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER)
1681                 rcu_assign_pointer(call->filter, filter);
1682         else
1683                 rcu_assign_pointer(file->filter, filter);
1684 }
1685
1686 static inline void event_clear_filter(struct ftrace_event_file *file)
1687 {
1688         struct ftrace_event_call *call = file->event_call;
1689
1690         if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER)
1691                 RCU_INIT_POINTER(call->filter, NULL);
1692         else
1693                 RCU_INIT_POINTER(file->filter, NULL);
1694 }
1695
1696 static inline void
1697 event_set_no_set_filter_flag(struct ftrace_event_file *file)
1698 {
1699         struct ftrace_event_call *call = file->event_call;
1700
1701         if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER)
1702                 call->flags |= TRACE_EVENT_FL_NO_SET_FILTER;
1703         else
1704                 file->flags |= FTRACE_EVENT_FL_NO_SET_FILTER;
1705 }
1706
1707 static inline void
1708 event_clear_no_set_filter_flag(struct ftrace_event_file *file)
1709 {
1710         struct ftrace_event_call *call = file->event_call;
1711
1712         if (call->flags & TRACE_EVENT_FL_USE_CALL_FILTER)
1713                 call->flags &= ~TRACE_EVENT_FL_NO_SET_FILTER;
1714         else
1715                 file->flags &= ~FTRACE_EVENT_FL_NO_SET_FILTER;
1716 }
1717
1718 static inline bool
1719 event_no_set_filter_flag(struct ftrace_event_file *file)
1720 {
1721         struct ftrace_event_call *call = file->event_call;
1722
1723         if (file->flags & FTRACE_EVENT_FL_NO_SET_FILTER)
1724                 return true;
1725
1726         if ((call->flags & TRACE_EVENT_FL_USE_CALL_FILTER) &&
1727             (call->flags & TRACE_EVENT_FL_NO_SET_FILTER))
1728                 return true;
1729
1730         return false;
1731 }
1732
1733 struct filter_list {
1734         struct list_head        list;
1735         struct event_filter     *filter;
1736 };
1737
1738 static int replace_system_preds(struct ftrace_subsystem_dir *dir,
1739                                 struct trace_array *tr,
1740                                 struct filter_parse_state *ps,
1741                                 char *filter_string)
1742 {
1743         struct ftrace_event_file *file;
1744         struct filter_list *filter_item;
1745         struct filter_list *tmp;
1746         LIST_HEAD(filter_list);
1747         bool fail = true;
1748         int err;
1749
1750         list_for_each_entry(file, &tr->events, list) {
1751                 if (file->system != dir)
1752                         continue;
1753
1754                 /*
1755                  * Try to see if the filter can be applied
1756                  *  (filter arg is ignored on dry_run)
1757                  */
1758                 err = replace_preds(file->event_call, NULL, ps, true);
1759                 if (err)
1760                         event_set_no_set_filter_flag(file);
1761                 else
1762                         event_clear_no_set_filter_flag(file);
1763         }
1764
1765         list_for_each_entry(file, &tr->events, list) {
1766                 struct event_filter *filter;
1767
1768                 if (file->system != dir)
1769                         continue;
1770
1771                 if (event_no_set_filter_flag(file))
1772                         continue;
1773
1774                 filter_item = kzalloc(sizeof(*filter_item), GFP_KERNEL);
1775                 if (!filter_item)
1776                         goto fail_mem;
1777
1778                 list_add_tail(&filter_item->list, &filter_list);
1779
1780                 filter_item->filter = __alloc_filter();
1781                 if (!filter_item->filter)
1782                         goto fail_mem;
1783                 filter = filter_item->filter;
1784
1785                 /* Can only fail on no memory */
1786                 err = replace_filter_string(filter, filter_string);
1787                 if (err)
1788                         goto fail_mem;
1789
1790                 err = replace_preds(file->event_call, filter, ps, false);
1791                 if (err) {
1792                         filter_disable(file);
1793                         parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
1794                         append_filter_err(ps, filter);
1795                 } else
1796                         event_set_filtered_flag(file);
1797                 /*
1798                  * Regardless of if this returned an error, we still
1799                  * replace the filter for the call.
1800                  */
1801                 filter = event_filter(file);
1802                 event_set_filter(file, filter_item->filter);
1803                 filter_item->filter = filter;
1804
1805                 fail = false;
1806         }
1807
1808         if (fail)
1809                 goto fail;
1810
1811         /*
1812          * The calls can still be using the old filters.
1813          * Do a synchronize_sched() to ensure all calls are
1814          * done with them before we free them.
1815          */
1816         synchronize_sched();
1817         list_for_each_entry_safe(filter_item, tmp, &filter_list, list) {
1818                 __free_filter(filter_item->filter);
1819                 list_del(&filter_item->list);
1820                 kfree(filter_item);
1821         }
1822         return 0;
1823  fail:
1824         /* No call succeeded */
1825         list_for_each_entry_safe(filter_item, tmp, &filter_list, list) {
1826                 list_del(&filter_item->list);
1827                 kfree(filter_item);
1828         }
1829         parse_error(ps, FILT_ERR_BAD_SUBSYS_FILTER, 0);
1830         return -EINVAL;
1831  fail_mem:
1832         /* If any call succeeded, we still need to sync */
1833         if (!fail)
1834                 synchronize_sched();
1835         list_for_each_entry_safe(filter_item, tmp, &filter_list, list) {
1836                 __free_filter(filter_item->filter);
1837                 list_del(&filter_item->list);
1838                 kfree(filter_item);
1839         }
1840         return -ENOMEM;
1841 }
1842
1843 static int create_filter_start(char *filter_str, bool set_str,
1844                                struct filter_parse_state **psp,
1845                                struct event_filter **filterp)
1846 {
1847         struct event_filter *filter;
1848         struct filter_parse_state *ps = NULL;
1849         int err = 0;
1850
1851         WARN_ON_ONCE(*psp || *filterp);
1852
1853         /* allocate everything, and if any fails, free all and fail */
1854         filter = __alloc_filter();
1855         if (filter && set_str)
1856                 err = replace_filter_string(filter, filter_str);
1857
1858         ps = kzalloc(sizeof(*ps), GFP_KERNEL);
1859
1860         if (!filter || !ps || err) {
1861                 kfree(ps);
1862                 __free_filter(filter);
1863                 return -ENOMEM;
1864         }
1865
1866         /* we're committed to creating a new filter */
1867         *filterp = filter;
1868         *psp = ps;
1869
1870         parse_init(ps, filter_ops, filter_str);
1871         err = filter_parse(ps);
1872         if (err && set_str)
1873                 append_filter_err(ps, filter);
1874         return err;
1875 }
1876
1877 static void create_filter_finish(struct filter_parse_state *ps)
1878 {
1879         if (ps) {
1880                 filter_opstack_clear(ps);
1881                 postfix_clear(ps);
1882                 kfree(ps);
1883         }
1884 }
1885
1886 /**
1887  * create_filter - create a filter for a ftrace_event_call
1888  * @call: ftrace_event_call to create a filter for
1889  * @filter_str: filter string
1890  * @set_str: remember @filter_str and enable detailed error in filter
1891  * @filterp: out param for created filter (always updated on return)
1892  *
1893  * Creates a filter for @call with @filter_str.  If @set_str is %true,
1894  * @filter_str is copied and recorded in the new filter.
1895  *
1896  * On success, returns 0 and *@filterp points to the new filter.  On
1897  * failure, returns -errno and *@filterp may point to %NULL or to a new
1898  * filter.  In the latter case, the returned filter contains error
1899  * information if @set_str is %true and the caller is responsible for
1900  * freeing it.
1901  */
1902 static int create_filter(struct ftrace_event_call *call,
1903                          char *filter_str, bool set_str,
1904                          struct event_filter **filterp)
1905 {
1906         struct event_filter *filter = NULL;
1907         struct filter_parse_state *ps = NULL;
1908         int err;
1909
1910         err = create_filter_start(filter_str, set_str, &ps, &filter);
1911         if (!err) {
1912                 err = replace_preds(call, filter, ps, false);
1913                 if (err && set_str)
1914                         append_filter_err(ps, filter);
1915         }
1916         create_filter_finish(ps);
1917
1918         *filterp = filter;
1919         return err;
1920 }
1921
1922 int create_event_filter(struct ftrace_event_call *call,
1923                         char *filter_str, bool set_str,
1924                         struct event_filter **filterp)
1925 {
1926         return create_filter(call, filter_str, set_str, filterp);
1927 }
1928
1929 /**
1930  * create_system_filter - create a filter for an event_subsystem
1931  * @system: event_subsystem to create a filter for
1932  * @filter_str: filter string
1933  * @filterp: out param for created filter (always updated on return)
1934  *
1935  * Identical to create_filter() except that it creates a subsystem filter
1936  * and always remembers @filter_str.
1937  */
1938 static int create_system_filter(struct ftrace_subsystem_dir *dir,
1939                                 struct trace_array *tr,
1940                                 char *filter_str, struct event_filter **filterp)
1941 {
1942         struct event_filter *filter = NULL;
1943         struct filter_parse_state *ps = NULL;
1944         int err;
1945
1946         err = create_filter_start(filter_str, true, &ps, &filter);
1947         if (!err) {
1948                 err = replace_system_preds(dir, tr, ps, filter_str);
1949                 if (!err) {
1950                         /* System filters just show a default message */
1951                         kfree(filter->filter_string);
1952                         filter->filter_string = NULL;
1953                 } else {
1954                         append_filter_err(ps, filter);
1955                 }
1956         }
1957         create_filter_finish(ps);
1958
1959         *filterp = filter;
1960         return err;
1961 }
1962
1963 /* caller must hold event_mutex */
1964 int apply_event_filter(struct ftrace_event_file *file, char *filter_string)
1965 {
1966         struct ftrace_event_call *call = file->event_call;
1967         struct event_filter *filter;
1968         int err;
1969
1970         if (!strcmp(strstrip(filter_string), "0")) {
1971                 filter_disable(file);
1972                 filter = event_filter(file);
1973
1974                 if (!filter)
1975                         return 0;
1976
1977                 event_clear_filter(file);
1978
1979                 /* Make sure the filter is not being used */
1980                 synchronize_sched();
1981                 __free_filter(filter);
1982
1983                 return 0;
1984         }
1985
1986         err = create_filter(call, filter_string, true, &filter);
1987
1988         /*
1989          * Always swap the call filter with the new filter
1990          * even if there was an error. If there was an error
1991          * in the filter, we disable the filter and show the error
1992          * string
1993          */
1994         if (filter) {
1995                 struct event_filter *tmp;
1996
1997                 tmp = event_filter(file);
1998                 if (!err)
1999                         event_set_filtered_flag(file);
2000                 else
2001                         filter_disable(file);
2002
2003                 event_set_filter(file, filter);
2004
2005                 if (tmp) {
2006                         /* Make sure the call is done with the filter */
2007                         synchronize_sched();
2008                         __free_filter(tmp);
2009                 }
2010         }
2011
2012         return err;
2013 }
2014
2015 int apply_subsystem_event_filter(struct ftrace_subsystem_dir *dir,
2016                                  char *filter_string)
2017 {
2018         struct event_subsystem *system = dir->subsystem;
2019         struct trace_array *tr = dir->tr;
2020         struct event_filter *filter;
2021         int err = 0;
2022
2023         mutex_lock(&event_mutex);
2024
2025         /* Make sure the system still has events */
2026         if (!dir->nr_events) {
2027                 err = -ENODEV;
2028                 goto out_unlock;
2029         }
2030
2031         if (!strcmp(strstrip(filter_string), "0")) {
2032                 filter_free_subsystem_preds(dir, tr);
2033                 remove_filter_string(system->filter);
2034                 filter = system->filter;
2035                 system->filter = NULL;
2036                 /* Ensure all filters are no longer used */
2037                 synchronize_sched();
2038                 filter_free_subsystem_filters(dir, tr);
2039                 __free_filter(filter);
2040                 goto out_unlock;
2041         }
2042
2043         err = create_system_filter(dir, tr, filter_string, &filter);
2044         if (filter) {
2045                 /*
2046                  * No event actually uses the system filter
2047                  * we can free it without synchronize_sched().
2048                  */
2049                 __free_filter(system->filter);
2050                 system->filter = filter;
2051         }
2052 out_unlock:
2053         mutex_unlock(&event_mutex);
2054
2055         return err;
2056 }
2057
2058 #ifdef CONFIG_PERF_EVENTS
2059
2060 void ftrace_profile_free_filter(struct perf_event *event)
2061 {
2062         struct event_filter *filter = event->filter;
2063
2064         event->filter = NULL;
2065         __free_filter(filter);
2066 }
2067
2068 struct function_filter_data {
2069         struct ftrace_ops *ops;
2070         int first_filter;
2071         int first_notrace;
2072 };
2073
2074 #ifdef CONFIG_FUNCTION_TRACER
2075 static char **
2076 ftrace_function_filter_re(char *buf, int len, int *count)
2077 {
2078         char *str, *sep, **re;
2079
2080         str = kstrndup(buf, len, GFP_KERNEL);
2081         if (!str)
2082                 return NULL;
2083
2084         /*
2085          * The argv_split function takes white space
2086          * as a separator, so convert ',' into spaces.
2087          */
2088         while ((sep = strchr(str, ',')))
2089                 *sep = ' ';
2090
2091         re = argv_split(GFP_KERNEL, str, count);
2092         kfree(str);
2093         return re;
2094 }
2095
2096 static int ftrace_function_set_regexp(struct ftrace_ops *ops, int filter,
2097                                       int reset, char *re, int len)
2098 {
2099         int ret;
2100
2101         if (filter)
2102                 ret = ftrace_set_filter(ops, re, len, reset);
2103         else
2104                 ret = ftrace_set_notrace(ops, re, len, reset);
2105
2106         return ret;
2107 }
2108
2109 static int __ftrace_function_set_filter(int filter, char *buf, int len,
2110                                         struct function_filter_data *data)
2111 {
2112         int i, re_cnt, ret = -EINVAL;
2113         int *reset;
2114         char **re;
2115
2116         reset = filter ? &data->first_filter : &data->first_notrace;
2117
2118         /*
2119          * The 'ip' field could have multiple filters set, separated
2120          * either by space or comma. We first cut the filter and apply
2121          * all pieces separatelly.
2122          */
2123         re = ftrace_function_filter_re(buf, len, &re_cnt);
2124         if (!re)
2125                 return -EINVAL;
2126
2127         for (i = 0; i < re_cnt; i++) {
2128                 ret = ftrace_function_set_regexp(data->ops, filter, *reset,
2129                                                  re[i], strlen(re[i]));
2130                 if (ret)
2131                         break;
2132
2133                 if (*reset)
2134                         *reset = 0;
2135         }
2136
2137         argv_free(re);
2138         return ret;
2139 }
2140
2141 static int ftrace_function_check_pred(struct filter_pred *pred, int leaf)
2142 {
2143         struct ftrace_event_field *field = pred->field;
2144
2145         if (leaf) {
2146                 /*
2147                  * Check the leaf predicate for function trace, verify:
2148                  *  - only '==' and '!=' is used
2149                  *  - the 'ip' field is used
2150                  */
2151                 if ((pred->op != OP_EQ) && (pred->op != OP_NE))
2152                         return -EINVAL;
2153
2154                 if (strcmp(field->name, "ip"))
2155                         return -EINVAL;
2156         } else {
2157                 /*
2158                  * Check the non leaf predicate for function trace, verify:
2159                  *  - only '||' is used
2160                 */
2161                 if (pred->op != OP_OR)
2162                         return -EINVAL;
2163         }
2164
2165         return 0;
2166 }
2167
2168 static int ftrace_function_set_filter_cb(enum move_type move,
2169                                          struct filter_pred *pred,
2170                                          int *err, void *data)
2171 {
2172         /* Checking the node is valid for function trace. */
2173         if ((move != MOVE_DOWN) ||
2174             (pred->left != FILTER_PRED_INVALID)) {
2175                 *err = ftrace_function_check_pred(pred, 0);
2176         } else {
2177                 *err = ftrace_function_check_pred(pred, 1);
2178                 if (*err)
2179                         return WALK_PRED_ABORT;
2180
2181                 *err = __ftrace_function_set_filter(pred->op == OP_EQ,
2182                                                     pred->regex.pattern,
2183                                                     pred->regex.len,
2184                                                     data);
2185         }
2186
2187         return (*err) ? WALK_PRED_ABORT : WALK_PRED_DEFAULT;
2188 }
2189
2190 static int ftrace_function_set_filter(struct perf_event *event,
2191                                       struct event_filter *filter)
2192 {
2193         struct function_filter_data data = {
2194                 .first_filter  = 1,
2195                 .first_notrace = 1,
2196                 .ops           = &event->ftrace_ops,
2197         };
2198
2199         return walk_pred_tree(filter->preds, filter->root,
2200                               ftrace_function_set_filter_cb, &data);
2201 }
2202 #else
2203 static int ftrace_function_set_filter(struct perf_event *event,
2204                                       struct event_filter *filter)
2205 {
2206         return -ENODEV;
2207 }
2208 #endif /* CONFIG_FUNCTION_TRACER */
2209
2210 int ftrace_profile_set_filter(struct perf_event *event, int event_id,
2211                               char *filter_str)
2212 {
2213         int err;
2214         struct event_filter *filter;
2215         struct ftrace_event_call *call;
2216
2217         mutex_lock(&event_mutex);
2218
2219         call = event->tp_event;
2220
2221         err = -EINVAL;
2222         if (!call)
2223                 goto out_unlock;
2224
2225         err = -EEXIST;
2226         if (event->filter)
2227                 goto out_unlock;
2228
2229         err = create_filter(call, filter_str, false, &filter);
2230         if (err)
2231                 goto free_filter;
2232
2233         if (ftrace_event_is_function(call))
2234                 err = ftrace_function_set_filter(event, filter);
2235         else
2236                 event->filter = filter;
2237
2238 free_filter:
2239         if (err || ftrace_event_is_function(call))
2240                 __free_filter(filter);
2241
2242 out_unlock:
2243         mutex_unlock(&event_mutex);
2244
2245         return err;
2246 }
2247
2248 #endif /* CONFIG_PERF_EVENTS */
2249
2250 #ifdef CONFIG_FTRACE_STARTUP_TEST
2251
2252 #include <linux/types.h>
2253 #include <linux/tracepoint.h>
2254
2255 #define CREATE_TRACE_POINTS
2256 #include "trace_events_filter_test.h"
2257
2258 #define DATA_REC(m, va, vb, vc, vd, ve, vf, vg, vh, nvisit) \
2259 { \
2260         .filter = FILTER, \
2261         .rec    = { .a = va, .b = vb, .c = vc, .d = vd, \
2262                     .e = ve, .f = vf, .g = vg, .h = vh }, \
2263         .match  = m, \
2264         .not_visited = nvisit, \
2265 }
2266 #define YES 1
2267 #define NO  0
2268
2269 static struct test_filter_data_t {
2270         char *filter;
2271         struct ftrace_raw_ftrace_test_filter rec;
2272         int match;
2273         char *not_visited;
2274 } test_filter_data[] = {
2275 #define FILTER "a == 1 && b == 1 && c == 1 && d == 1 && " \
2276                "e == 1 && f == 1 && g == 1 && h == 1"
2277         DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, ""),
2278         DATA_REC(NO,  0, 1, 1, 1, 1, 1, 1, 1, "bcdefgh"),
2279         DATA_REC(NO,  1, 1, 1, 1, 1, 1, 1, 0, ""),
2280 #undef FILTER
2281 #define FILTER "a == 1 || b == 1 || c == 1 || d == 1 || " \
2282                "e == 1 || f == 1 || g == 1 || h == 1"
2283         DATA_REC(NO,  0, 0, 0, 0, 0, 0, 0, 0, ""),
2284         DATA_REC(YES, 0, 0, 0, 0, 0, 0, 0, 1, ""),
2285         DATA_REC(YES, 1, 0, 0, 0, 0, 0, 0, 0, "bcdefgh"),
2286 #undef FILTER
2287 #define FILTER "(a == 1 || b == 1) && (c == 1 || d == 1) && " \
2288                "(e == 1 || f == 1) && (g == 1 || h == 1)"
2289         DATA_REC(NO,  0, 0, 1, 1, 1, 1, 1, 1, "dfh"),
2290         DATA_REC(YES, 0, 1, 0, 1, 0, 1, 0, 1, ""),
2291         DATA_REC(YES, 1, 0, 1, 0, 0, 1, 0, 1, "bd"),
2292         DATA_REC(NO,  1, 0, 1, 0, 0, 1, 0, 0, "bd"),
2293 #undef FILTER
2294 #define FILTER "(a == 1 && b == 1) || (c == 1 && d == 1) || " \
2295                "(e == 1 && f == 1) || (g == 1 && h == 1)"
2296         DATA_REC(YES, 1, 0, 1, 1, 1, 1, 1, 1, "efgh"),
2297         DATA_REC(YES, 0, 0, 0, 0, 0, 0, 1, 1, ""),
2298         DATA_REC(NO,  0, 0, 0, 0, 0, 0, 0, 1, ""),
2299 #undef FILTER
2300 #define FILTER "(a == 1 && b == 1) && (c == 1 && d == 1) && " \
2301                "(e == 1 && f == 1) || (g == 1 && h == 1)"
2302         DATA_REC(YES, 1, 1, 1, 1, 1, 1, 0, 0, "gh"),
2303         DATA_REC(NO,  0, 0, 0, 0, 0, 0, 0, 1, ""),
2304         DATA_REC(YES, 1, 1, 1, 1, 1, 0, 1, 1, ""),
2305 #undef FILTER
2306 #define FILTER "((a == 1 || b == 1) || (c == 1 || d == 1) || " \
2307                "(e == 1 || f == 1)) && (g == 1 || h == 1)"
2308         DATA_REC(YES, 1, 1, 1, 1, 1, 1, 0, 1, "bcdef"),
2309         DATA_REC(NO,  0, 0, 0, 0, 0, 0, 0, 0, ""),
2310         DATA_REC(YES, 1, 1, 1, 1, 1, 0, 1, 1, "h"),
2311 #undef FILTER
2312 #define FILTER "((((((((a == 1) && (b == 1)) || (c == 1)) && (d == 1)) || " \
2313                "(e == 1)) && (f == 1)) || (g == 1)) && (h == 1))"
2314         DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, "ceg"),
2315         DATA_REC(NO,  0, 1, 0, 1, 0, 1, 0, 1, ""),
2316         DATA_REC(NO,  1, 0, 1, 0, 1, 0, 1, 0, ""),
2317 #undef FILTER
2318 #define FILTER "((((((((a == 1) || (b == 1)) && (c == 1)) || (d == 1)) && " \
2319                "(e == 1)) || (f == 1)) && (g == 1)) || (h == 1))"
2320         DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, "bdfh"),
2321         DATA_REC(YES, 0, 1, 0, 1, 0, 1, 0, 1, ""),
2322         DATA_REC(YES, 1, 0, 1, 0, 1, 0, 1, 0, "bdfh"),
2323 };
2324
2325 #undef DATA_REC
2326 #undef FILTER
2327 #undef YES
2328 #undef NO
2329
2330 #define DATA_CNT (sizeof(test_filter_data)/sizeof(struct test_filter_data_t))
2331
2332 static int test_pred_visited;
2333
2334 static int test_pred_visited_fn(struct filter_pred *pred, void *event)
2335 {
2336         struct ftrace_event_field *field = pred->field;
2337
2338         test_pred_visited = 1;
2339         printk(KERN_INFO "\npred visited %s\n", field->name);
2340         return 1;
2341 }
2342
2343 static int test_walk_pred_cb(enum move_type move, struct filter_pred *pred,
2344                              int *err, void *data)
2345 {
2346         char *fields = data;
2347
2348         if ((move == MOVE_DOWN) &&
2349             (pred->left == FILTER_PRED_INVALID)) {
2350                 struct ftrace_event_field *field = pred->field;
2351
2352                 if (!field) {
2353                         WARN(1, "all leafs should have field defined");
2354                         return WALK_PRED_DEFAULT;
2355                 }
2356                 if (!strchr(fields, *field->name))
2357                         return WALK_PRED_DEFAULT;
2358
2359                 WARN_ON(!pred->fn);
2360                 pred->fn = test_pred_visited_fn;
2361         }
2362         return WALK_PRED_DEFAULT;
2363 }
2364
2365 static __init int ftrace_test_event_filter(void)
2366 {
2367         int i;
2368
2369         printk(KERN_INFO "Testing ftrace filter: ");
2370
2371         for (i = 0; i < DATA_CNT; i++) {
2372                 struct event_filter *filter = NULL;
2373                 struct test_filter_data_t *d = &test_filter_data[i];
2374                 int err;
2375
2376                 err = create_filter(&event_ftrace_test_filter, d->filter,
2377                                     false, &filter);
2378                 if (err) {
2379                         printk(KERN_INFO
2380                                "Failed to get filter for '%s', err %d\n",
2381                                d->filter, err);
2382                         __free_filter(filter);
2383                         break;
2384                 }
2385
2386                 /*
2387                  * The preemption disabling is not really needed for self
2388                  * tests, but the rcu dereference will complain without it.
2389                  */
2390                 preempt_disable();
2391                 if (*d->not_visited)
2392                         walk_pred_tree(filter->preds, filter->root,
2393                                        test_walk_pred_cb,
2394                                        d->not_visited);
2395
2396                 test_pred_visited = 0;
2397                 err = filter_match_preds(filter, &d->rec);
2398                 preempt_enable();
2399
2400                 __free_filter(filter);
2401
2402                 if (test_pred_visited) {
2403                         printk(KERN_INFO
2404                                "Failed, unwanted pred visited for filter %s\n",
2405                                d->filter);
2406                         break;
2407                 }
2408
2409                 if (err != d->match) {
2410                         printk(KERN_INFO
2411                                "Failed to match filter '%s', expected %d\n",
2412                                d->filter, d->match);
2413                         break;
2414                 }
2415         }
2416
2417         if (i == DATA_CNT)
2418                 printk(KERN_CONT "OK\n");
2419
2420         return 0;
2421 }
2422
2423 late_initcall(ftrace_test_event_filter);
2424
2425 #endif /* CONFIG_FTRACE_STARTUP_TEST */