1	// SPDX-License-Identifier: GPL-2.0
2	/*
3	* trace_events_filter - generic event filtering
4	*
5	* Copyright (C) 2009 Tom Zanussi <tzanussi@gmail.com>
6	*/
7
8	#include <linux/uaccess.h>
9	#include <linux/module.h>
10	#include <linux/ctype.h>
11	#include <linux/mutex.h>
12	#include <linux/perf_event.h>
13	#include <linux/slab.h>
14
15	#include "trace.h"
16	#include "trace_output.h"
17
18	#define DEFAULT_SYS_FILTER_MESSAGE \
19	"### global filter ###\n" \
20	"# Use this to set filters for multiple events.\n" \
21	"# Only events with the given fields will be affected.\n" \
22	"# If no events are modified, an error message will be displayed here"
23
24	/* Due to token parsing '<=' must be before '<' and '>=' must be before '>' */
25	#define OPS \
26	C( OP_GLOB, "~" ), \
27	C( OP_NE, "!=" ), \
28	C( OP_EQ, "==" ), \
29	C( OP_LE, "<=" ), \
30	C( OP_LT, "<" ), \
31	C( OP_GE, ">=" ), \
32	C( OP_GT, ">" ), \
33	C( OP_BAND, "&" ), \
34	C( OP_MAX, NULL )
35
36	#undef C
37	#define C(a, b) a
38
39	enum filter_op_ids { OPS };
40
41	#undef C
42	#define C(a, b) b
43
44	static const char * ops[] = { OPS };
45
46	enum filter_pred_fn {
47	FILTER_PRED_FN_NOP,
48	FILTER_PRED_FN_64,
49	FILTER_PRED_FN_64_CPUMASK,
50	FILTER_PRED_FN_S64,
51	FILTER_PRED_FN_U64,
52	FILTER_PRED_FN_32,
53	FILTER_PRED_FN_32_CPUMASK,
54	FILTER_PRED_FN_S32,
55	FILTER_PRED_FN_U32,
56	FILTER_PRED_FN_16,
57	FILTER_PRED_FN_16_CPUMASK,
58	FILTER_PRED_FN_S16,
59	FILTER_PRED_FN_U16,
60	FILTER_PRED_FN_8,
61	FILTER_PRED_FN_8_CPUMASK,
62	FILTER_PRED_FN_S8,
63	FILTER_PRED_FN_U8,
64	FILTER_PRED_FN_COMM,
65	FILTER_PRED_FN_STRING,
66	FILTER_PRED_FN_STRLOC,
67	FILTER_PRED_FN_STRRELLOC,
68	FILTER_PRED_FN_PCHAR_USER,
69	FILTER_PRED_FN_PCHAR,
70	FILTER_PRED_FN_CPU,
71	FILTER_PRED_FN_CPU_CPUMASK,
72	FILTER_PRED_FN_CPUMASK,
73	FILTER_PRED_FN_CPUMASK_CPU,
74	FILTER_PRED_FN_FUNCTION,
75	FILTER_PRED_FN_,
76	FILTER_PRED_TEST_VISITED,
77	};
78
79	struct filter_pred {
80	struct regex *regex;
81	struct cpumask *mask;
82	unsigned short *ops;
83	struct ftrace_event_field *field;
84	u64 val;
85	u64 val2;
86	enum filter_pred_fn fn_num;
87	int offset;
88	int not;
89	int op;
90	};
91
92	/*
93	* pred functions are OP_LE, OP_LT, OP_GE, OP_GT, and OP_BAND
94	* pred_funcs_##type below must match the order of them above.
95	*/
96	#define PRED_FUNC_START OP_LE
97	#define PRED_FUNC_MAX (OP_BAND - PRED_FUNC_START)
98
99	#define ERRORS \
100	C(NONE, "No error"), \
101	C(INVALID_OP, "Invalid operator"), \
102	C(TOO_MANY_OPEN, "Too many '('"), \
103	C(TOO_MANY_CLOSE, "Too few '('"), \
104	C(MISSING_QUOTE, "Missing matching quote"), \
105	C(MISSING_BRACE_OPEN, "Missing '{'"), \
106	C(MISSING_BRACE_CLOSE, "Missing '}'"), \
107	C(OPERAND_TOO_LONG, "Operand too long"), \
108	C(EXPECT_STRING, "Expecting string field"), \
109	C(EXPECT_DIGIT, "Expecting numeric field"), \
110	C(ILLEGAL_FIELD_OP, "Illegal operation for field type"), \
111	C(FIELD_NOT_FOUND, "Field not found"), \
112	C(ILLEGAL_INTVAL, "Illegal integer value"), \
113	C(BAD_SUBSYS_FILTER, "Couldn't find or set field in one of a subsystem's events"), \
114	C(TOO_MANY_PREDS, "Too many terms in predicate expression"), \
115	C(INVALID_FILTER, "Meaningless filter expression"), \
116	C(INVALID_CPULIST, "Invalid cpulist"), \
117	C(IP_FIELD_ONLY, "Only 'ip' field is supported for function trace"), \
118	C(INVALID_VALUE, "Invalid value (did you forget quotes)?"), \
119	C(NO_FUNCTION, "Function not found"), \
120	C(ERRNO, "Error"), \
121	C(NO_FILTER, "No filter found")
122
123	#undef C
124	#define C(a, b) FILT_ERR_##a
125
126	enum { ERRORS };
127
128	#undef C
129	#define C(a, b) b
130
131	static const char *err_text[] = { ERRORS };
132
133	/* Called after a '!' character but "!=" and "!~" are not "not"s */
134	static bool is_not(const char *str)
135	{
136	switch (str[1]) {
137	case '=':
138	case '~':
139	return false;
140	}
141	return true;
142	}
143
144	/**
145	* struct prog_entry - a single entry in the filter program
146	* @target: Index to jump to on a branch (actually one minus the index)
147	* @when_to_branch: The value of the result of the predicate to do a branch
148	* @pred: The predicate to execute.
149	*/
150	struct prog_entry {
151	int target;
152	int when_to_branch;
153	struct filter_pred *pred;
154	};
155
156	/**
157	* update_preds - assign a program entry a label target
158	* @prog: The program array
159	* @N: The index of the current entry in @prog
160	* @invert: What to assign a program entry for its branch condition
161	*
162	* The program entry at @N has a target that points to the index of a program
163	* entry that can have its target and when_to_branch fields updated.
164	* Update the current program entry denoted by index @N target field to be
165	* that of the updated entry. This will denote the entry to update if
166	* we are processing an "||" after an "&&".
167	*/
168	static void update_preds(struct prog_entry *prog, int N, int invert)
169	{
170	int t, s;
171
172	t = prog[N].target;
173	s = prog[t].target;
174	prog[t].when_to_branch = invert;
175	prog[t].target = N;
176	prog[N].target = s;
177	}
178
179	struct filter_parse_error {
180	int lasterr;
181	int lasterr_pos;
182	};
183
184	static void parse_error(struct filter_parse_error *pe, int err, int pos)
185	{
186	pe->lasterr = err;
187	pe->lasterr_pos = pos;
188	}
189
190	typedef int (*parse_pred_fn)(const char *str, void *data, int pos,
191	struct filter_parse_error *pe,
192	struct filter_pred **pred);
193
194	enum {
195	INVERT = 1,
196	PROCESS_AND = 2,
197	PROCESS_OR = 4,
198	};
199
200	static void free_predicate(struct filter_pred *pred)
201	{
202	if (pred) {
203	kfree(objp: pred->regex);
204	kfree(objp: pred->mask);
205	kfree(objp: pred);
206	}
207	}
208
209	/*
210	* Without going into a formal proof, this explains the method that is used in
211	* parsing the logical expressions.
212	*
213	* For example, if we have: "a && !(!b || (c && g)) || d || e && !f"
214	* The first pass will convert it into the following program:
215	*
216	* n1: r=a; l1: if (!r) goto l4;
217	* n2: r=b; l2: if (!r) goto l4;
218	* n3: r=c; r=!r; l3: if (r) goto l4;
219	* n4: r=g; r=!r; l4: if (r) goto l5;
220	* n5: r=d; l5: if (r) goto T
221	* n6: r=e; l6: if (!r) goto l7;
222	* n7: r=f; r=!r; l7: if (!r) goto F
223	* T: return TRUE
224	* F: return FALSE
225	*
226	* To do this, we use a data structure to represent each of the above
227	* predicate and conditions that has:
228	*
229	* predicate, when_to_branch, invert, target
230	*
231	* The "predicate" will hold the function to determine the result "r".
232	* The "when_to_branch" denotes what "r" should be if a branch is to be taken
233	* "&&" would contain "!r" or (0) and "||" would contain "r" or (1).
234	* The "invert" holds whether the value should be reversed before testing.
235	* The "target" contains the label "l#" to jump to.
236	*
237	* A stack is created to hold values when parentheses are used.
238	*
239	* To simplify the logic, the labels will start at 0 and not 1.
240	*
241	* The possible invert values are 1 and 0. The number of "!"s that are in scope
242	* before the predicate determines the invert value, if the number is odd then
243	* the invert value is 1 and 0 otherwise. This means the invert value only
244	* needs to be toggled when a new "!" is introduced compared to what is stored
245	* on the stack, where parentheses were used.
246	*
247	* The top of the stack and "invert" are initialized to zero.
248	*
249	* ** FIRST PASS **
250	*
251	* #1 A loop through all the tokens is done:
252	*
253	* #2 If the token is an "(", the stack is push, and the current stack value
254	* gets the current invert value, and the loop continues to the next token.
255	* The top of the stack saves the "invert" value to keep track of what
256	* the current inversion is. As "!(a && !b || c)" would require all
257	* predicates being affected separately by the "!" before the parentheses.
258	* And that would end up being equivalent to "(!a || b) && !c"
259	*
260	* #3 If the token is an "!", the current "invert" value gets inverted, and
261	* the loop continues. Note, if the next token is a predicate, then
262	* this "invert" value is only valid for the current program entry,
263	* and does not affect other predicates later on.
264	*
265	* The only other acceptable token is the predicate string.
266	*
267	* #4 A new entry into the program is added saving: the predicate and the
268	* current value of "invert". The target is currently assigned to the
269	* previous program index (this will not be its final value).
270	*
271	* #5 We now enter another loop and look at the next token. The only valid
272	* tokens are ")", "&&", "||" or end of the input string "\0".
273	*
274	* #6 The invert variable is reset to the current value saved on the top of
275	* the stack.
276	*
277	* #7 The top of the stack holds not only the current invert value, but also
278	* if a "&&" or "||" needs to be processed. Note, the "&&" takes higher
279	* precedence than "||". That is "a && b || c && d" is equivalent to
280	* "(a && b) || (c && d)". Thus the first thing to do is to see if "&&" needs
281	* to be processed. This is the case if an "&&" was the last token. If it was
282	* then we call update_preds(). This takes the program, the current index in
283	* the program, and the current value of "invert". More will be described
284	* below about this function.
285	*
286	* #8 If the next token is "&&" then we set a flag in the top of the stack
287	* that denotes that "&&" needs to be processed, break out of this loop
288	* and continue with the outer loop.
289	*
290	* #9 Otherwise, if a "||" needs to be processed then update_preds() is called.
291	* This is called with the program, the current index in the program, but
292	* this time with an inverted value of "invert" (that is !invert). This is
293	* because the value taken will become the "when_to_branch" value of the
294	* program.
295	* Note, this is called when the next token is not an "&&". As stated before,
296	* "&&" takes higher precedence, and "||" should not be processed yet if the
297	* next logical operation is "&&".
298	*
299	* #10 If the next token is "||" then we set a flag in the top of the stack
300	* that denotes that "||" needs to be processed, break out of this loop
301	* and continue with the outer loop.
302	*
303	* #11 If this is the end of the input string "\0" then we break out of both
304	* loops.
305	*
306	* #12 Otherwise, the next token is ")", where we pop the stack and continue
307	* this inner loop.
308	*
309	* Now to discuss the update_pred() function, as that is key to the setting up
310	* of the program. Remember the "target" of the program is initialized to the
311	* previous index and not the "l" label. The target holds the index into the
312	* program that gets affected by the operand. Thus if we have something like
313	* "a || b && c", when we process "a" the target will be "-1" (undefined).
314	* When we process "b", its target is "0", which is the index of "a", as that's
315	* the predicate that is affected by "||". But because the next token after "b"
316	* is "&&" we don't call update_preds(). Instead continue to "c". As the
317	* next token after "c" is not "&&" but the end of input, we first process the
318	* "&&" by calling update_preds() for the "&&" then we process the "||" by
319	* calling updates_preds() with the values for processing "||".
320	*
321	* What does that mean? What update_preds() does is to first save the "target"
322	* of the program entry indexed by the current program entry's "target"
323	* (remember the "target" is initialized to previous program entry), and then
324	* sets that "target" to the current index which represents the label "l#".
325	* That entry's "when_to_branch" is set to the value passed in (the "invert"
326	* or "!invert"). Then it sets the current program entry's target to the saved
327	* "target" value (the old value of the program that had its "target" updated
328	* to the label).
329	*
330	* Looking back at "a || b && c", we have the following steps:
331	* "a" - prog[0] = { "a", X, -1 } // pred, when_to_branch, target
332	* "||" - flag that we need to process "||"; continue outer loop
333	* "b" - prog[1] = { "b", X, 0 }
334	* "&&" - flag that we need to process "&&"; continue outer loop
335	* (Notice we did not process "||")
336	* "c" - prog[2] = { "c", X, 1 }
337	* update_preds(prog, 2, 0); // invert = 0 as we are processing "&&"
338	* t = prog[2].target; // t = 1
339	* s = prog[t].target; // s = 0
340	* prog[t].target = 2; // Set target to "l2"
341	* prog[t].when_to_branch = 0;
342	* prog[2].target = s;
343	* update_preds(prog, 2, 1); // invert = 1 as we are now processing "||"
344	* t = prog[2].target; // t = 0
345	* s = prog[t].target; // s = -1
346	* prog[t].target = 2; // Set target to "l2"
347	* prog[t].when_to_branch = 1;
348	* prog[2].target = s;
349	*
350	* #13 Which brings us to the final step of the first pass, which is to set
351	* the last program entry's when_to_branch and target, which will be
352	* when_to_branch = 0; target = N; ( the label after the program entry after
353	* the last program entry processed above).
354	*
355	* If we denote "TRUE" to be the entry after the last program entry processed,
356	* and "FALSE" the program entry after that, we are now done with the first
357	* pass.
358	*
359	* Making the above "a || b && c" have a program of:
360	* prog[0] = { "a", 1, 2 }
361	* prog[1] = { "b", 0, 2 }
362	* prog[2] = { "c", 0, 3 }
363	*
364	* Which translates into:
365	* n0: r = a; l0: if (r) goto l2;
366	* n1: r = b; l1: if (!r) goto l2;
367	* n2: r = c; l2: if (!r) goto l3; // Which is the same as "goto F;"
368	* T: return TRUE; l3:
369	* F: return FALSE
370	*
371	* Although, after the first pass, the program is correct, it is
372	* inefficient. The simple sample of "a || b && c" could be easily been
373	* converted into:
374	* n0: r = a; if (r) goto T
375	* n1: r = b; if (!r) goto F
376	* n2: r = c; if (!r) goto F
377	* T: return TRUE;
378	* F: return FALSE;
379	*
380	* The First Pass is over the input string. The next too passes are over
381	* the program itself.
382	*
383	* ** SECOND PASS **
384	*
385	* Which brings us to the second pass. If a jump to a label has the
386	* same condition as that label, it can instead jump to its target.
387	* The original example of "a && !(!b || (c && g)) || d || e && !f"
388	* where the first pass gives us:
389	*
390	* n1: r=a; l1: if (!r) goto l4;
391	* n2: r=b; l2: if (!r) goto l4;
392	* n3: r=c; r=!r; l3: if (r) goto l4;
393	* n4: r=g; r=!r; l4: if (r) goto l5;
394	* n5: r=d; l5: if (r) goto T
395	* n6: r=e; l6: if (!r) goto l7;
396	* n7: r=f; r=!r; l7: if (!r) goto F:
397	* T: return TRUE;
398	* F: return FALSE
399	*
400	* We can see that "l3: if (r) goto l4;" and at l4, we have "if (r) goto l5;".
401	* And "l5: if (r) goto T", we could optimize this by converting l3 and l4
402	* to go directly to T. To accomplish this, we start from the last
403	* entry in the program and work our way back. If the target of the entry
404	* has the same "when_to_branch" then we could use that entry's target.
405	* Doing this, the above would end up as:
406	*
407	* n1: r=a; l1: if (!r) goto l4;
408	* n2: r=b; l2: if (!r) goto l4;
409	* n3: r=c; r=!r; l3: if (r) goto T;
410	* n4: r=g; r=!r; l4: if (r) goto T;
411	* n5: r=d; l5: if (r) goto T;
412	* n6: r=e; l6: if (!r) goto F;
413	* n7: r=f; r=!r; l7: if (!r) goto F;
414	* T: return TRUE
415	* F: return FALSE
416	*
417	* In that same pass, if the "when_to_branch" doesn't match, we can simply
418	* go to the program entry after the label. That is, "l2: if (!r) goto l4;"
419	* where "l4: if (r) goto T;", then we can convert l2 to be:
420	* "l2: if (!r) goto n5;".
421	*
422	* This will have the second pass give us:
423	* n1: r=a; l1: if (!r) goto n5;
424	* n2: r=b; l2: if (!r) goto n5;
425	* n3: r=c; r=!r; l3: if (r) goto T;
426	* n4: r=g; r=!r; l4: if (r) goto T;
427	* n5: r=d; l5: if (r) goto T
428	* n6: r=e; l6: if (!r) goto F;
429	* n7: r=f; r=!r; l7: if (!r) goto F
430	* T: return TRUE
431	* F: return FALSE
432	*
433	* Notice, all the "l#" labels are no longer used, and they can now
434	* be discarded.
435	*
436	* ** THIRD PASS **
437	*
438	* For the third pass we deal with the inverts. As they simply just
439	* make the "when_to_branch" get inverted, a simple loop over the
440	* program to that does: "when_to_branch ^= invert;" will do the
441	* job, leaving us with:
442	* n1: r=a; if (!r) goto n5;
443	* n2: r=b; if (!r) goto n5;
444	* n3: r=c: if (!r) goto T;
445	* n4: r=g; if (!r) goto T;
446	* n5: r=d; if (r) goto T
447	* n6: r=e; if (!r) goto F;
448	* n7: r=f; if (r) goto F
449	* T: return TRUE
450	* F: return FALSE
451	*
452	* As "r = a; if (!r) goto n5;" is obviously the same as
453	* "if (!a) goto n5;" without doing anything we can interpret the
454	* program as:
455	* n1: if (!a) goto n5;
456	* n2: if (!b) goto n5;
457	* n3: if (!c) goto T;
458	* n4: if (!g) goto T;
459	* n5: if (d) goto T
460	* n6: if (!e) goto F;
461	* n7: if (f) goto F
462	* T: return TRUE
463	* F: return FALSE
464	*
465	* Since the inverts are discarded at the end, there's no reason to store
466	* them in the program array (and waste memory). A separate array to hold
467	* the inverts is used and freed at the end.
468	*/
469	static struct prog_entry *
470	predicate_parse(const char *str, int nr_parens, int nr_preds,
471	parse_pred_fn parse_pred, void *data,
472	struct filter_parse_error *pe)
473	{
474	struct prog_entry *prog_stack;
475	struct prog_entry *prog;
476	const char *ptr = str;
477	char *inverts = NULL;
478	int *op_stack;
479	int *top;
480	int invert = 0;
481	int ret = -ENOMEM;
482	int len;
483	int N = 0;
484	int i;
485
486	nr_preds += 2; /* For TRUE and FALSE */
487
488	op_stack = kmalloc_array(nr_parens, sizeof(*op_stack), GFP_KERNEL);
489	if (!op_stack)
490	return ERR_PTR(error: -ENOMEM);
491	prog_stack = kcalloc(nr_preds, sizeof(*prog_stack), GFP_KERNEL);
492	if (!prog_stack) {
493	parse_error(pe, err: -ENOMEM, pos: 0);
494	goto out_free;
495	}
496	inverts = kmalloc_array(nr_preds, sizeof(*inverts), GFP_KERNEL);
497	if (!inverts) {
498	parse_error(pe, err: -ENOMEM, pos: 0);
499	goto out_free;
500	}
501
502	top = op_stack;
503	prog = prog_stack;
504	*top = 0;
505
506	/* First pass */
507	while (*ptr) { /* #1 */
508	const char *next = ptr++;
509
510	if (isspace(*next))
511	continue;
512
513	switch (*next) {
514	case '(': /* #2 */
515	if (top - op_stack > nr_parens) {
516	ret = -EINVAL;
517	goto out_free;
518	}
519	*(++top) = invert;
520	continue;
521	case '!': /* #3 */
522	if (!is_not(str: next))
523	break;
524	invert = !invert;
525	continue;
526	}
527
528	if (N >= nr_preds) {
529	parse_error(pe, err: FILT_ERR_TOO_MANY_PREDS, pos: next - str);
530	goto out_free;
531	}
532
533	inverts[N] = invert; /* #4 */
534	prog[N].target = N-1;
535
536	len = parse_pred(next, data, ptr - str, pe, &prog[N].pred);
537	if (len < 0) {
538	ret = len;
539	goto out_free;
540	}
541	ptr = next + len;
542
543	N++;
544
545	ret = -1;
546	while (1) { /* #5 */
547	next = ptr++;
548	if (isspace(*next))
549	continue;
550
551	switch (*next) {
552	case ')':
553	case '\0':
554	break;
555	case '&':
556	case '|':
557	/* accepting only "&&" or "||" */
558	if (next[1] == next[0]) {
559	ptr++;
560	break;
561	}
562	fallthrough;
563	default:
564	parse_error(pe, err: FILT_ERR_TOO_MANY_PREDS,
565	pos: next - str);
566	goto out_free;
567	}
568
569	invert = *top & INVERT;
570
571	if (*top & PROCESS_AND) { /* #7 */
572	update_preds(prog, N: N - 1, invert);
573	*top &= ~PROCESS_AND;
574	}
575	if (*next == '&') { /* #8 */
576	*top |= PROCESS_AND;
577	break;
578	}
579	if (*top & PROCESS_OR) { /* #9 */
580	update_preds(prog, N: N - 1, invert: !invert);
581	*top &= ~PROCESS_OR;
582	}
583	if (*next == '|') { /* #10 */
584	*top |= PROCESS_OR;
585	break;
586	}
587	if (!*next) /* #11 */
588	goto out;
589
590	if (top == op_stack) {
591	ret = -1;
592	/* Too few '(' */
593	parse_error(pe, err: FILT_ERR_TOO_MANY_CLOSE, pos: ptr - str);
594	goto out_free;
595	}
596	top--; /* #12 */
597	}
598	}
599	out:
600	if (top != op_stack) {
601	/* Too many '(' */
602	parse_error(pe, err: FILT_ERR_TOO_MANY_OPEN, pos: ptr - str);
603	goto out_free;
604	}
605
606	if (!N) {
607	/* No program? */
608	ret = -EINVAL;
609	parse_error(pe, err: FILT_ERR_NO_FILTER, pos: ptr - str);
610	goto out_free;
611	}
612
613	prog[N].pred = NULL; /* #13 */
614	prog[N].target = 1; /* TRUE */
615	prog[N+1].pred = NULL;
616	prog[N+1].target = 0; /* FALSE */
617	prog[N-1].target = N;
618	prog[N-1].when_to_branch = false;
619
620	/* Second Pass */
621	for (i = N-1 ; i--; ) {
622	int target = prog[i].target;
623	if (prog[i].when_to_branch == prog[target].when_to_branch)
624	prog[i].target = prog[target].target;
625	}
626
627	/* Third Pass */
628	for (i = 0; i < N; i++) {
629	invert = inverts[i] ^ prog[i].when_to_branch;
630	prog[i].when_to_branch = invert;
631	/* Make sure the program always moves forward */
632	if (WARN_ON(prog[i].target <= i)) {
633	ret = -EINVAL;
634	goto out_free;
635	}
636	}
637
638	kfree(objp: op_stack);
639	kfree(objp: inverts);
640	return prog;
641	out_free:
642	kfree(objp: op_stack);
643	kfree(objp: inverts);
644	if (prog_stack) {
645	for (i = 0; prog_stack[i].pred; i++)
646	free_predicate(pred: prog_stack[i].pred);
647	kfree(objp: prog_stack);
648	}
649	return ERR_PTR(error: ret);
650	}
651
652	static inline int
653	do_filter_cpumask(int op, const struct cpumask *mask, const struct cpumask *cmp)
654	{
655	switch (op) {
656	case OP_EQ:
657	return cpumask_equal(src1p: mask, src2p: cmp);
658	case OP_NE:
659	return !cpumask_equal(src1p: mask, src2p: cmp);
660	case OP_BAND:
661	return cpumask_intersects(src1p: mask, src2p: cmp);
662	default:
663	return 0;
664	}
665	}
666
667	/* Optimisation of do_filter_cpumask() for scalar fields */
668	static inline int
669	do_filter_scalar_cpumask(int op, unsigned int cpu, const struct cpumask *mask)
670	{
671	/*
672	* Per the weight-of-one cpumask optimisations, the mask passed in this
673	* function has a weight >= 2, so it is never equal to a single scalar.
674	*/
675	switch (op) {
676	case OP_EQ:
677	return false;
678	case OP_NE:
679	return true;
680	case OP_BAND:
681	return cpumask_test_cpu(cpu, cpumask: mask);
682	default:
683	return 0;
684	}
685	}
686
687	static inline int
688	do_filter_cpumask_scalar(int op, const struct cpumask *mask, unsigned int cpu)
689	{
690	switch (op) {
691	case OP_EQ:
692	return cpumask_test_cpu(cpu, cpumask: mask) &&
693	cpumask_nth(cpu: 1, srcp: mask) >= nr_cpu_ids;
694	case OP_NE:
695	return !cpumask_test_cpu(cpu, cpumask: mask) ||
696	cpumask_nth(cpu: 1, srcp: mask) < nr_cpu_ids;
697	case OP_BAND:
698	return cpumask_test_cpu(cpu, cpumask: mask);
699	default:
700	return 0;
701	}
702	}
703
704	enum pred_cmp_types {
705	PRED_CMP_TYPE_NOP,
706	PRED_CMP_TYPE_LT,
707	PRED_CMP_TYPE_LE,
708	PRED_CMP_TYPE_GT,
709	PRED_CMP_TYPE_GE,
710	PRED_CMP_TYPE_BAND,
711	};
712
713	#define DEFINE_COMPARISON_PRED(type) \
714	static int filter_pred_##type(struct filter_pred *pred, void *event) \
715	{ \
716	switch (pred->op) { \
717	case OP_LT: { \
718	type *addr = (type *)(event + pred->offset); \
719	type val = (type)pred->val; \
720	return *addr < val; \
721	} \
722	case OP_LE: { \
723	type *addr = (type *)(event + pred->offset); \
724	type val = (type)pred->val; \
725	return *addr <= val; \
726	} \
727	case OP_GT: { \
728	type *addr = (type *)(event + pred->offset); \
729	type val = (type)pred->val; \
730	return *addr > val; \
731	} \
732	case OP_GE: { \
733	type *addr = (type *)(event + pred->offset); \
734	type val = (type)pred->val; \
735	return *addr >= val; \
736	} \
737	case OP_BAND: { \
738	type *addr = (type *)(event + pred->offset); \
739	type val = (type)pred->val; \
740	return !!(*addr & val); \
741	} \
742	default: \
743	return 0; \
744	} \
745	}
746
747	#define DEFINE_CPUMASK_COMPARISON_PRED(size) \
748	static int filter_pred_##size##_cpumask(struct filter_pred *pred, void *event) \
749	{ \
750	u##size *addr = (u##size *)(event + pred->offset); \
751	unsigned int cpu = *addr; \
752	\
753	if (cpu >= nr_cpu_ids) \
754	return 0; \
755	\
756	return do_filter_scalar_cpumask(pred->op, cpu, pred->mask); \
757	}
758
759	#define DEFINE_EQUALITY_PRED(size) \
760	static int filter_pred_##size(struct filter_pred *pred, void *event) \
761	{ \
762	u##size *addr = (u##size *)(event + pred->offset); \
763	u##size val = (u##size)pred->val; \
764	int match; \
765	\
766	match = (val == *addr) ^ pred->not; \
767	\
768	return match; \
769	}
770
771	DEFINE_COMPARISON_PRED(s64);
772	DEFINE_COMPARISON_PRED(u64);
773	DEFINE_COMPARISON_PRED(s32);
774	DEFINE_COMPARISON_PRED(u32);
775	DEFINE_COMPARISON_PRED(s16);
776	DEFINE_COMPARISON_PRED(u16);
777	DEFINE_COMPARISON_PRED(s8);
778	DEFINE_COMPARISON_PRED(u8);
779
780	DEFINE_CPUMASK_COMPARISON_PRED(64);
781	DEFINE_CPUMASK_COMPARISON_PRED(32);
782	DEFINE_CPUMASK_COMPARISON_PRED(16);
783	DEFINE_CPUMASK_COMPARISON_PRED(8);
784
785	DEFINE_EQUALITY_PRED(64);
786	DEFINE_EQUALITY_PRED(32);
787	DEFINE_EQUALITY_PRED(16);
788	DEFINE_EQUALITY_PRED(8);
789
790	/* user space strings temp buffer */
791	#define USTRING_BUF_SIZE 1024
792
793	struct ustring_buffer {
794	char buffer[USTRING_BUF_SIZE];
795	};
796
797	static __percpu struct ustring_buffer *ustring_per_cpu;
798
799	static __always_inline char *test_string(char *str)
800	{
801	struct ustring_buffer *ubuf;
802	char *kstr;
803
804	if (!ustring_per_cpu)
805	return NULL;
806
807	ubuf = this_cpu_ptr(ustring_per_cpu);
808	kstr = ubuf->buffer;
809
810	/* For safety, do not trust the string pointer */
811	if (strncpy_from_kernel_nofault(dst: kstr, unsafe_addr: str, USTRING_BUF_SIZE) < 0)
812	return NULL;
813	return kstr;
814	}
815
816	static __always_inline char *test_ustring(char *str)
817	{
818	struct ustring_buffer *ubuf;
819	char __user *ustr;
820	char *kstr;
821
822	if (!ustring_per_cpu)
823	return NULL;
824
825	ubuf = this_cpu_ptr(ustring_per_cpu);
826	kstr = ubuf->buffer;
827
828	/* user space address? */
829	ustr = (char __user *)str;
830	if (strncpy_from_user_nofault(dst: kstr, unsafe_addr: ustr, USTRING_BUF_SIZE) < 0)
831	return NULL;
832
833	return kstr;
834	}
835
836	/* Filter predicate for fixed sized arrays of characters */
837	static int filter_pred_string(struct filter_pred *pred, void *event)
838	{
839	char *addr = (char *)(event + pred->offset);
840	int cmp, match;
841
842	cmp = pred->regex->match(addr, pred->regex, pred->regex->field_len);
843
844	match = cmp ^ pred->not;
845
846	return match;
847	}
848
849	static __always_inline int filter_pchar(struct filter_pred *pred, char *str)
850	{
851	int cmp, match;
852	int len;
853
854	len = strlen(str) + 1; /* including tailing '\0' */
855	cmp = pred->regex->match(str, pred->regex, len);
856
857	match = cmp ^ pred->not;
858
859	return match;
860	}
861	/* Filter predicate for char * pointers */
862	static int filter_pred_pchar(struct filter_pred *pred, void *event)
863	{
864	char **addr = (char **)(event + pred->offset);
865	char *str;
866
867	str = test_string(str: *addr);
868	if (!str)
869	return 0;
870
871	return filter_pchar(pred, str);
872	}
873
874	/* Filter predicate for char * pointers in user space*/
875	static int filter_pred_pchar_user(struct filter_pred *pred, void *event)
876	{
877	char **addr = (char **)(event + pred->offset);
878	char *str;
879
880	str = test_ustring(str: *addr);
881	if (!str)
882	return 0;
883
884	return filter_pchar(pred, str);
885	}
886
887	/*
888	* Filter predicate for dynamic sized arrays of characters.
889	* These are implemented through a list of strings at the end
890	* of the entry.
891	* Also each of these strings have a field in the entry which
892	* contains its offset from the beginning of the entry.
893	* We have then first to get this field, dereference it
894	* and add it to the address of the entry, and at last we have
895	* the address of the string.
896	*/
897	static int filter_pred_strloc(struct filter_pred *pred, void *event)
898	{
899	u32 str_item = *(u32 *)(event + pred->offset);
900	int str_loc = str_item & 0xffff;
901	int str_len = str_item >> 16;
902	char *addr = (char *)(event + str_loc);
903	int cmp, match;
904
905	cmp = pred->regex->match(addr, pred->regex, str_len);
906
907	match = cmp ^ pred->not;
908
909	return match;
910	}
911
912	/*
913	* Filter predicate for relative dynamic sized arrays of characters.
914	* These are implemented through a list of strings at the end
915	* of the entry as same as dynamic string.
916	* The difference is that the relative one records the location offset
917	* from the field itself, not the event entry.
918	*/
919	static int filter_pred_strrelloc(struct filter_pred *pred, void *event)
920	{
921	u32 *item = (u32 *)(event + pred->offset);
922	u32 str_item = *item;
923	int str_loc = str_item & 0xffff;
924	int str_len = str_item >> 16;
925	char *addr = (char *)(&item[1]) + str_loc;
926	int cmp, match;
927
928	cmp = pred->regex->match(addr, pred->regex, str_len);
929
930	match = cmp ^ pred->not;
931
932	return match;
933	}
934
935	/* Filter predicate for CPUs. */
936	static int filter_pred_cpu(struct filter_pred *pred, void *event)
937	{
938	int cpu, cmp;
939
940	cpu = raw_smp_processor_id();
941	cmp = pred->val;
942
943	switch (pred->op) {
944	case OP_EQ:
945	return cpu == cmp;
946	case OP_NE:
947	return cpu != cmp;
948	case OP_LT:
949	return cpu < cmp;
950	case OP_LE:
951	return cpu <= cmp;
952	case OP_GT:
953	return cpu > cmp;
954	case OP_GE:
955	return cpu >= cmp;
956	default:
957	return 0;
958	}
959	}
960
961	/* Filter predicate for current CPU vs user-provided cpumask */
962	static int filter_pred_cpu_cpumask(struct filter_pred *pred, void *event)
963	{
964	int cpu = raw_smp_processor_id();
965
966	return do_filter_scalar_cpumask(op: pred->op, cpu, mask: pred->mask);
967	}
968
969	/* Filter predicate for cpumask field vs user-provided cpumask */
970	static int filter_pred_cpumask(struct filter_pred *pred, void *event)
971	{
972	u32 item = *(u32 *)(event + pred->offset);
973	int loc = item & 0xffff;
974	const struct cpumask *mask = (event + loc);
975	const struct cpumask *cmp = pred->mask;
976
977	return do_filter_cpumask(op: pred->op, mask, cmp);
978	}
979
980	/* Filter predicate for cpumask field vs user-provided scalar */
981	static int filter_pred_cpumask_cpu(struct filter_pred *pred, void *event)
982	{
983	u32 item = *(u32 *)(event + pred->offset);
984	int loc = item & 0xffff;
985	const struct cpumask *mask = (event + loc);
986	unsigned int cpu = pred->val;
987
988	return do_filter_cpumask_scalar(op: pred->op, mask, cpu);
989	}
990
991	/* Filter predicate for COMM. */
992	static int filter_pred_comm(struct filter_pred *pred, void *event)
993	{
994	int cmp;
995
996	cmp = pred->regex->match(current->comm, pred->regex,
997	TASK_COMM_LEN);
998	return cmp ^ pred->not;
999	}
1000
1001	/* Filter predicate for functions. */
1002	static int filter_pred_function(struct filter_pred *pred, void *event)
1003	{
1004	unsigned long *addr = (unsigned long *)(event + pred->offset);
1005	unsigned long start = (unsigned long)pred->val;
1006	unsigned long end = (unsigned long)pred->val2;
1007	int ret = *addr >= start && *addr < end;
1008
1009	return pred->op == OP_EQ ? ret : !ret;
1010	}
1011
1012	/*
1013	* regex_match_foo - Basic regex callbacks
1014	*
1015	* @str: the string to be searched
1016	* @r: the regex structure containing the pattern string
1017	* @len: the length of the string to be searched (including '\0')
1018	*
1019	* Note:
1020	* - @str might not be NULL-terminated if it's of type DYN_STRING
1021	* RDYN_STRING, or STATIC_STRING, unless @len is zero.
1022	*/
1023
1024	static int regex_match_full(char *str, struct regex *r, int len)
1025	{
1026	/* len of zero means str is dynamic and ends with '\0' */
1027	if (!len)
1028	return strcmp(str, r->pattern) == 0;
1029
1030	return strncmp(str, r->pattern, len) == 0;
1031	}
1032
1033	static int regex_match_front(char *str, struct regex *r, int len)
1034	{
1035	if (len && len < r->len)
1036	return 0;
1037
1038	return strncmp(str, r->pattern, r->len) == 0;
1039	}
1040
1041	static int regex_match_middle(char *str, struct regex *r, int len)
1042	{
1043	if (!len)
1044	return strstr(str, r->pattern) != NULL;
1045
1046	return strnstr(str, r->pattern, len) != NULL;
1047	}
1048
1049	static int regex_match_end(char *str, struct regex *r, int len)
1050	{
1051	int strlen = len - 1;
1052
1053	if (strlen >= r->len &&
1054	memcmp(p: str + strlen - r->len, q: r->pattern, size: r->len) == 0)
1055	return 1;
1056	return 0;
1057	}
1058
1059	static int regex_match_glob(char *str, struct regex *r, int len __maybe_unused)
1060	{
1061	if (glob_match(pat: r->pattern, str))
1062	return 1;
1063	return 0;
1064	}
1065
1066	/**
1067	* filter_parse_regex - parse a basic regex
1068	* @buff: the raw regex
1069	* @len: length of the regex
1070	* @search: will point to the beginning of the string to compare
1071	* @not: tell whether the match will have to be inverted
1072	*
1073	* This passes in a buffer containing a regex and this function will
1074	* set search to point to the search part of the buffer and
1075	* return the type of search it is (see enum above).
1076	* This does modify buff.
1077	*
1078	* Returns enum type.
1079	* search returns the pointer to use for comparison.
1080	* not returns 1 if buff started with a '!'
1081	* 0 otherwise.
1082	*/
1083	enum regex_type filter_parse_regex(char *buff, int len, char **search, int *not)
1084	{
1085	int type = MATCH_FULL;
1086	int i;
1087
1088	if (buff[0] == '!') {
1089	*not = 1;
1090	buff++;
1091	len--;
1092	} else
1093	*not = 0;
1094
1095	*search = buff;
1096
1097	if (isdigit(c: buff[0]))
1098	return MATCH_INDEX;
1099
1100	for (i = 0; i < len; i++) {
1101	if (buff[i] == '*') {
1102	if (!i) {
1103	type = MATCH_END_ONLY;
1104	} else if (i == len - 1) {
1105	if (type == MATCH_END_ONLY)
1106	type = MATCH_MIDDLE_ONLY;
1107	else
1108	type = MATCH_FRONT_ONLY;
1109	buff[i] = 0;
1110	break;
1111	} else { /* pattern continues, use full glob */
1112	return MATCH_GLOB;
1113	}
1114	} else if (strchr("[?\\", buff[i])) {
1115	return MATCH_GLOB;
1116	}
1117	}
1118	if (buff[0] == '*')
1119	*search = buff + 1;
1120
1121	return type;
1122	}
1123
1124	static void filter_build_regex(struct filter_pred *pred)
1125	{
1126	struct regex *r = pred->regex;
1127	char *search;
1128	enum regex_type type = MATCH_FULL;
1129
1130	if (pred->op == OP_GLOB) {
1131	type = filter_parse_regex(buff: r->pattern, len: r->len, search: &search, not: &pred->not);
1132	r->len = strlen(search);
1133	memmove(r->pattern, search, r->len+1);
1134	}
1135
1136	switch (type) {
1137	/* MATCH_INDEX should not happen, but if it does, match full */
1138	case MATCH_INDEX:
1139	case MATCH_FULL:
1140	r->match = regex_match_full;
1141	break;
1142	case MATCH_FRONT_ONLY:
1143	r->match = regex_match_front;
1144	break;
1145	case MATCH_MIDDLE_ONLY:
1146	r->match = regex_match_middle;
1147	break;
1148	case MATCH_END_ONLY:
1149	r->match = regex_match_end;
1150	break;
1151	case MATCH_GLOB:
1152	r->match = regex_match_glob;
1153	break;
1154	}
1155	}
1156
1157
1158	#ifdef CONFIG_FTRACE_STARTUP_TEST
1159	static int test_pred_visited_fn(struct filter_pred *pred, void *event);
1160	#else
1161	static int test_pred_visited_fn(struct filter_pred *pred, void *event)
1162	{
1163	return 0;
1164	}
1165	#endif
1166
1167
1168	static int filter_pred_fn_call(struct filter_pred *pred, void *event);
1169
1170	/* return 1 if event matches, 0 otherwise (discard) */
1171	int filter_match_preds(struct event_filter *filter, void *rec)
1172	{
1173	struct prog_entry *prog;
1174	int i;
1175
1176	/* no filter is considered a match */
1177	if (!filter)
1178	return 1;
1179
1180	/* Protected by either SRCU(tracepoint_srcu) or preempt_disable */
1181	prog = rcu_dereference_raw(filter->prog);
1182	if (!prog)
1183	return 1;
1184
1185	for (i = 0; prog[i].pred; i++) {
1186	struct filter_pred *pred = prog[i].pred;
1187	int match = filter_pred_fn_call(pred, event: rec);
1188	if (match == prog[i].when_to_branch)
1189	i = prog[i].target;
1190	}
1191	return prog[i].target;
1192	}
1193	EXPORT_SYMBOL_GPL(filter_match_preds);
1194
1195	static void remove_filter_string(struct event_filter *filter)
1196	{
1197	if (!filter)
1198	return;
1199
1200	kfree(objp: filter->filter_string);
1201	filter->filter_string = NULL;
1202	}
1203
1204	static void append_filter_err(struct trace_array *tr,
1205	struct filter_parse_error *pe,
1206	struct event_filter *filter)
1207	{
1208	struct trace_seq *s;
1209	int pos = pe->lasterr_pos;
1210	char *buf;
1211	int len;
1212
1213	if (WARN_ON(!filter->filter_string))
1214	return;
1215
1216	s = kmalloc(sizeof(*s), GFP_KERNEL);
1217	if (!s)
1218	return;
1219	trace_seq_init(s);
1220
1221	len = strlen(filter->filter_string);
1222	if (pos > len)
1223	pos = len;
1224
1225	/* indexing is off by one */
1226	if (pos)
1227	pos++;
1228
1229	trace_seq_puts(s, str: filter->filter_string);
1230	if (pe->lasterr > 0) {
1231	trace_seq_printf(s, fmt: "\n%*s", pos, "^");
1232	trace_seq_printf(s, fmt: "\nparse_error: %s\n", err_text[pe->lasterr]);
1233	tracing_log_err(tr, loc: "event filter parse error",
1234	cmd: filter->filter_string, errs: err_text,
1235	type: pe->lasterr, pos: pe->lasterr_pos);
1236	} else {
1237	trace_seq_printf(s, fmt: "\nError: (%d)\n", pe->lasterr);
1238	tracing_log_err(tr, loc: "event filter parse error",
1239	cmd: filter->filter_string, errs: err_text,
1240	type: FILT_ERR_ERRNO, pos: 0);
1241	}
1242	trace_seq_putc(s, c: 0);
1243	buf = kmemdup_nul(s: s->buffer, len: s->seq.len, GFP_KERNEL);
1244	if (buf) {
1245	kfree(objp: filter->filter_string);
1246	filter->filter_string = buf;
1247	}
1248	kfree(objp: s);
1249	}
1250
1251	static inline struct event_filter *event_filter(struct trace_event_file *file)
1252	{
1253	return rcu_dereference_protected(file->filter,
1254	lockdep_is_held(&event_mutex));
1255
1256	}
1257
1258	/* caller must hold event_mutex */
1259	void print_event_filter(struct trace_event_file *file, struct trace_seq *s)
1260	{
1261	struct event_filter *filter = event_filter(file);
1262
1263	if (filter && filter->filter_string)
1264	trace_seq_printf(s, fmt: "%s\n", filter->filter_string);
1265	else
1266	trace_seq_puts(s, str: "none\n");
1267	}
1268
1269	void print_subsystem_event_filter(struct event_subsystem *system,
1270	struct trace_seq *s)
1271	{
1272	struct event_filter *filter;
1273
1274	mutex_lock(&event_mutex);
1275	filter = system->filter;
1276	if (filter && filter->filter_string)
1277	trace_seq_printf(s, fmt: "%s\n", filter->filter_string);
1278	else
1279	trace_seq_puts(s, DEFAULT_SYS_FILTER_MESSAGE "\n");
1280	mutex_unlock(lock: &event_mutex);
1281	}
1282
1283	static void free_prog(struct event_filter *filter)
1284	{
1285	struct prog_entry *prog;
1286	int i;
1287
1288	prog = rcu_access_pointer(filter->prog);
1289	if (!prog)
1290	return;
1291
1292	for (i = 0; prog[i].pred; i++)
1293	free_predicate(pred: prog[i].pred);
1294	kfree(objp: prog);
1295	}
1296
1297	static void filter_disable(struct trace_event_file *file)
1298	{
1299	unsigned long old_flags = file->flags;
1300
1301	file->flags &= ~EVENT_FILE_FL_FILTERED;
1302
1303	if (old_flags != file->flags)
1304	trace_buffered_event_disable();
1305	}
1306
1307	static void __free_filter(struct event_filter *filter)
1308	{
1309	if (!filter)
1310	return;
1311
1312	free_prog(filter);
1313	kfree(objp: filter->filter_string);
1314	kfree(objp: filter);
1315	}
1316
1317	void free_event_filter(struct event_filter *filter)
1318	{
1319	__free_filter(filter);
1320	}
1321
1322	static inline void __remove_filter(struct trace_event_file *file)
1323	{
1324	filter_disable(file);
1325	remove_filter_string(filter: event_filter(file));
1326	}
1327
1328	static void filter_free_subsystem_preds(struct trace_subsystem_dir *dir,
1329	struct trace_array *tr)
1330	{
1331	struct trace_event_file *file;
1332
1333	list_for_each_entry(file, &tr->events, list) {
1334	if (file->system != dir)
1335	continue;
1336	__remove_filter(file);
1337	}
1338	}
1339
1340	struct filter_list {
1341	struct list_head list;
1342	struct event_filter *filter;
1343	};
1344
1345	struct filter_head {
1346	struct list_head list;
1347	union {
1348	struct rcu_head rcu;
1349	struct rcu_work rwork;
1350	};
1351	};
1352
1353	static void free_filter_list(struct filter_head *filter_list)
1354	{
1355	struct filter_list *filter_item, *tmp;
1356
1357	list_for_each_entry_safe(filter_item, tmp, &filter_list->list, list) {
1358	__free_filter(filter: filter_item->filter);
1359	list_del(entry: &filter_item->list);
1360	kfree(objp: filter_item);
1361	}
1362	kfree(objp: filter_list);
1363	}
1364
1365	static void free_filter_list_work(struct work_struct *work)
1366	{
1367	struct filter_head *filter_list;
1368
1369	filter_list = container_of(to_rcu_work(work), struct filter_head, rwork);
1370	free_filter_list(filter_list);
1371	}
1372
1373	static void free_filter_list_tasks(struct rcu_head *rhp)
1374	{
1375	struct filter_head *filter_list = container_of(rhp, struct filter_head, rcu);
1376
1377	INIT_RCU_WORK(&filter_list->rwork, free_filter_list_work);
1378	queue_rcu_work(wq: system_wq, rwork: &filter_list->rwork);
1379	}
1380
1381	/*
1382	* The tracepoint_synchronize_unregister() is a double rcu call.
1383	* It calls synchronize_rcu_tasks_trace() followed by synchronize_rcu().
1384	* Instead of waiting for it, simply call these via the call_rcu*()
1385	* variants.
1386	*/
1387	static void delay_free_filter(struct filter_head *head)
1388	{
1389	call_rcu_tasks_trace(rhp: &head->rcu, func: free_filter_list_tasks);
1390	}
1391
1392	static void try_delay_free_filter(struct event_filter *filter)
1393	{
1394	struct filter_head *head;
1395	struct filter_list *item;
1396
1397	head = kmalloc(sizeof(*head), GFP_KERNEL);
1398	if (!head)
1399	goto free_now;
1400
1401	INIT_LIST_HEAD(list: &head->list);
1402
1403	item = kmalloc(sizeof(*item), GFP_KERNEL);
1404	if (!item) {
1405	kfree(objp: head);
1406	goto free_now;
1407	}
1408
1409	item->filter = filter;
1410	list_add_tail(new: &item->list, head: &head->list);
1411	delay_free_filter(head);
1412	return;
1413
1414	free_now:
1415	/* Make sure the filter is not being used */
1416	tracepoint_synchronize_unregister();
1417	__free_filter(filter);
1418	}
1419
1420	static inline void __free_subsystem_filter(struct trace_event_file *file)
1421	{
1422	__free_filter(filter: event_filter(file));
1423	file->filter = NULL;
1424	}
1425
1426	static inline void event_set_filter(struct trace_event_file *file,
1427	struct event_filter *filter)
1428	{
1429	rcu_assign_pointer(file->filter, filter);
1430	}
1431
1432	static inline void event_clear_filter(struct trace_event_file *file)
1433	{
1434	RCU_INIT_POINTER(file->filter, NULL);
1435	}
1436
1437	static void filter_free_subsystem_filters(struct trace_subsystem_dir *dir,
1438	struct trace_array *tr,
1439	struct event_filter *filter)
1440	{
1441	struct trace_event_file *file;
1442	struct filter_head *head;
1443	struct filter_list *item;
1444
1445	head = kmalloc(sizeof(*head), GFP_KERNEL);
1446	if (!head)
1447	goto free_now;
1448
1449	INIT_LIST_HEAD(list: &head->list);
1450
1451	list_for_each_entry(file, &tr->events, list) {
1452	if (file->system != dir)
1453	continue;
1454	item = kmalloc(sizeof(*item), GFP_KERNEL);
1455	if (!item)
1456	goto free_now;
1457	item->filter = event_filter(file);
1458	list_add_tail(new: &item->list, head: &head->list);
1459	event_clear_filter(file);
1460	}
1461
1462	item = kmalloc(sizeof(*item), GFP_KERNEL);
1463	if (!item)
1464	goto free_now;
1465
1466	item->filter = filter;
1467	list_add_tail(new: &item->list, head: &head->list);
1468
1469	delay_free_filter(head);
1470	return;
1471	free_now:
1472	tracepoint_synchronize_unregister();
1473
1474	if (head)
1475	free_filter_list(filter_list: head);
1476
1477	list_for_each_entry(file, &tr->events, list) {
1478	if (file->system != dir || !file->filter)
1479	continue;
1480	__free_subsystem_filter(file);
1481	}
1482	__free_filter(filter);
1483	}
1484
1485	int filter_assign_type(const char *type)
1486	{
1487	if (strstr(type, "__data_loc")) {
1488	if (strstr(type, "char"))
1489	return FILTER_DYN_STRING;
1490	if (strstr(type, "cpumask_t"))
1491	return FILTER_CPUMASK;
1492	}
1493
1494	if (strstr(type, "__rel_loc") && strstr(type, "char"))
1495	return FILTER_RDYN_STRING;
1496
1497	if (strchr(type, '[') && strstr(type, "char"))
1498	return FILTER_STATIC_STRING;
1499
1500	if (strcmp(type, "char *") == 0 || strcmp(type, "const char *") == 0)
1501	return FILTER_PTR_STRING;
1502
1503	return FILTER_OTHER;
1504	}
1505
1506	static enum filter_pred_fn select_comparison_fn(enum filter_op_ids op,
1507	int field_size, int field_is_signed)
1508	{
1509	enum filter_pred_fn fn = FILTER_PRED_FN_NOP;
1510	int pred_func_index = -1;
1511
1512	switch (op) {
1513	case OP_EQ:
1514	case OP_NE:
1515	break;
1516	default:
1517	if (WARN_ON_ONCE(op < PRED_FUNC_START))
1518	return fn;
1519	pred_func_index = op - PRED_FUNC_START;
1520	if (WARN_ON_ONCE(pred_func_index > PRED_FUNC_MAX))
1521	return fn;
1522	}
1523
1524	switch (field_size) {
1525	case 8:
1526	if (pred_func_index < 0)
1527	fn = FILTER_PRED_FN_64;
1528	else if (field_is_signed)
1529	fn = FILTER_PRED_FN_S64;
1530	else
1531	fn = FILTER_PRED_FN_U64;
1532	break;
1533	case 4:
1534	if (pred_func_index < 0)
1535	fn = FILTER_PRED_FN_32;
1536	else if (field_is_signed)
1537	fn = FILTER_PRED_FN_S32;
1538	else
1539	fn = FILTER_PRED_FN_U32;
1540	break;
1541	case 2:
1542	if (pred_func_index < 0)
1543	fn = FILTER_PRED_FN_16;
1544	else if (field_is_signed)
1545	fn = FILTER_PRED_FN_S16;
1546	else
1547	fn = FILTER_PRED_FN_U16;
1548	break;
1549	case 1:
1550	if (pred_func_index < 0)
1551	fn = FILTER_PRED_FN_8;
1552	else if (field_is_signed)
1553	fn = FILTER_PRED_FN_S8;
1554	else
1555	fn = FILTER_PRED_FN_U8;
1556	break;
1557	}
1558
1559	return fn;
1560	}
1561
1562
1563	static int filter_pred_fn_call(struct filter_pred *pred, void *event)
1564	{
1565	switch (pred->fn_num) {
1566	case FILTER_PRED_FN_64:
1567	return filter_pred_64(pred, event);
1568	case FILTER_PRED_FN_64_CPUMASK:
1569	return filter_pred_64_cpumask(pred, event);
1570	case FILTER_PRED_FN_S64:
1571	return filter_pred_s64(pred, event);
1572	case FILTER_PRED_FN_U64:
1573	return filter_pred_u64(pred, event);
1574	case FILTER_PRED_FN_32:
1575	return filter_pred_32(pred, event);
1576	case FILTER_PRED_FN_32_CPUMASK:
1577	return filter_pred_32_cpumask(pred, event);
1578	case FILTER_PRED_FN_S32:
1579	return filter_pred_s32(pred, event);
1580	case FILTER_PRED_FN_U32:
1581	return filter_pred_u32(pred, event);
1582	case FILTER_PRED_FN_16:
1583	return filter_pred_16(pred, event);
1584	case FILTER_PRED_FN_16_CPUMASK:
1585	return filter_pred_16_cpumask(pred, event);
1586	case FILTER_PRED_FN_S16:
1587	return filter_pred_s16(pred, event);
1588	case FILTER_PRED_FN_U16:
1589	return filter_pred_u16(pred, event);
1590	case FILTER_PRED_FN_8:
1591	return filter_pred_8(pred, event);
1592	case FILTER_PRED_FN_8_CPUMASK:
1593	return filter_pred_8_cpumask(pred, event);
1594	case FILTER_PRED_FN_S8:
1595	return filter_pred_s8(pred, event);
1596	case FILTER_PRED_FN_U8:
1597	return filter_pred_u8(pred, event);
1598	case FILTER_PRED_FN_COMM:
1599	return filter_pred_comm(pred, event);
1600	case FILTER_PRED_FN_STRING:
1601	return filter_pred_string(pred, event);
1602	case FILTER_PRED_FN_STRLOC:
1603	return filter_pred_strloc(pred, event);
1604	case FILTER_PRED_FN_STRRELLOC:
1605	return filter_pred_strrelloc(pred, event);
1606	case FILTER_PRED_FN_PCHAR_USER:
1607	return filter_pred_pchar_user(pred, event);
1608	case FILTER_PRED_FN_PCHAR:
1609	return filter_pred_pchar(pred, event);
1610	case FILTER_PRED_FN_CPU:
1611	return filter_pred_cpu(pred, event);
1612	case FILTER_PRED_FN_CPU_CPUMASK:
1613	return filter_pred_cpu_cpumask(pred, event);
1614	case FILTER_PRED_FN_CPUMASK:
1615	return filter_pred_cpumask(pred, event);
1616	case FILTER_PRED_FN_CPUMASK_CPU:
1617	return filter_pred_cpumask_cpu(pred, event);
1618	case FILTER_PRED_FN_FUNCTION:
1619	return filter_pred_function(pred, event);
1620	case FILTER_PRED_TEST_VISITED:
1621	return test_pred_visited_fn(pred, event);
1622	default:
1623	return 0;
1624	}
1625	}
1626
1627	/* Called when a predicate is encountered by predicate_parse() */
1628	static int parse_pred(const char *str, void *data,
1629	int pos, struct filter_parse_error *pe,
1630	struct filter_pred **pred_ptr)
1631	{
1632	struct trace_event_call *call = data;
1633	struct ftrace_event_field *field;
1634	struct filter_pred *pred = NULL;
1635	unsigned long offset;
1636	unsigned long size;
1637	unsigned long ip;
1638	char num_buf[24]; /* Big enough to hold an address */
1639	char *field_name;
1640	char *name;
1641	bool function = false;
1642	bool ustring = false;
1643	char q;
1644	u64 val;
1645	int len;
1646	int ret;
1647	int op;
1648	int s;
1649	int i = 0;
1650
1651	/* First find the field to associate to */
1652	while (isspace(str[i]))
1653	i++;
1654	s = i;
1655
1656	while (isalnum(str[i]) || str[i] == '_')
1657	i++;
1658
1659	len = i - s;
1660
1661	if (!len)
1662	return -1;
1663
1664	field_name = kmemdup_nul(s: str + s, len, GFP_KERNEL);
1665	if (!field_name)
1666	return -ENOMEM;
1667
1668	/* Make sure that the field exists */
1669
1670	field = trace_find_event_field(call, name: field_name);
1671	kfree(objp: field_name);
1672	if (!field) {
1673	parse_error(pe, err: FILT_ERR_FIELD_NOT_FOUND, pos: pos + i);
1674	return -EINVAL;
1675	}
1676
1677	/* See if the field is a user space string */
1678	if ((len = str_has_prefix(str: str + i, prefix: ".ustring"))) {
1679	ustring = true;
1680	i += len;
1681	}
1682
1683	/* See if the field is a kernel function name */
1684	if ((len = str_has_prefix(str: str + i, prefix: ".function"))) {
1685	function = true;
1686	i += len;
1687	}
1688
1689	while (isspace(str[i]))
1690	i++;
1691
1692	/* Make sure this op is supported */
1693	for (op = 0; ops[op]; op++) {
1694	/* This is why '<=' must come before '<' in ops[] */
1695	if (strncmp(str + i, ops[op], strlen(ops[op])) == 0)
1696	break;
1697	}
1698
1699	if (!ops[op]) {
1700	parse_error(pe, err: FILT_ERR_INVALID_OP, pos: pos + i);
1701	goto err_free;
1702	}
1703
1704	i += strlen(ops[op]);
1705
1706	while (isspace(str[i]))
1707	i++;
1708
1709	s = i;
1710
1711	pred = kzalloc(sizeof(*pred), GFP_KERNEL);
1712	if (!pred)
1713	return -ENOMEM;
1714
1715	pred->field = field;
1716	pred->offset = field->offset;
1717	pred->op = op;
1718
1719	if (function) {
1720	/* The field must be the same size as long */
1721	if (field->size != sizeof(long)) {
1722	parse_error(pe, err: FILT_ERR_ILLEGAL_FIELD_OP, pos: pos + i);
1723	goto err_free;
1724	}
1725
1726	/* Function only works with '==' or '!=' and an unquoted string */
1727	switch (op) {
1728	case OP_NE:
1729	case OP_EQ:
1730	break;
1731	default:
1732	parse_error(pe, err: FILT_ERR_INVALID_OP, pos: pos + i);
1733	goto err_free;
1734	}
1735
1736	if (isdigit(c: str[i])) {
1737	/* We allow 0xDEADBEEF */
1738	while (isalnum(str[i]))
1739	i++;
1740
1741	len = i - s;
1742	/* 0xfeedfacedeadbeef is 18 chars max */
1743	if (len >= sizeof(num_buf)) {
1744	parse_error(pe, err: FILT_ERR_OPERAND_TOO_LONG, pos: pos + i);
1745	goto err_free;
1746	}
1747
1748	memcpy(num_buf, str + s, len);
1749	num_buf[len] = 0;
1750
1751	ret = kstrtoul(s: num_buf, base: 0, res: &ip);
1752	if (ret) {
1753	parse_error(pe, err: FILT_ERR_INVALID_VALUE, pos: pos + i);
1754	goto err_free;
1755	}
1756	} else {
1757	s = i;
1758	for (; str[i] && !isspace(str[i]); i++)
1759	;
1760
1761	len = i - s;
1762	name = kmemdup_nul(s: str + s, len, GFP_KERNEL);
1763	if (!name)
1764	goto err_mem;
1765	ip = kallsyms_lookup_name(name);
1766	kfree(objp: name);
1767	if (!ip) {
1768	parse_error(pe, err: FILT_ERR_NO_FUNCTION, pos: pos + i);
1769	goto err_free;
1770	}
1771	}
1772
1773	/* Now find the function start and end address */
1774	if (!kallsyms_lookup_size_offset(addr: ip, symbolsize: &size, offset: &offset)) {
1775	parse_error(pe, err: FILT_ERR_NO_FUNCTION, pos: pos + i);
1776	goto err_free;
1777	}
1778
1779	pred->fn_num = FILTER_PRED_FN_FUNCTION;
1780	pred->val = ip - offset;
1781	pred->val2 = pred->val + size;
1782
1783	} else if (ftrace_event_is_function(call)) {
1784	/*
1785	* Perf does things different with function events.
1786	* It only allows an "ip" field, and expects a string.
1787	* But the string does not need to be surrounded by quotes.
1788	* If it is a string, the assigned function as a nop,
1789	* (perf doesn't use it) and grab everything.
1790	*/
1791	if (strcmp(field->name, "ip") != 0) {
1792	parse_error(pe, err: FILT_ERR_IP_FIELD_ONLY, pos: pos + i);
1793	goto err_free;
1794	}
1795	pred->fn_num = FILTER_PRED_FN_NOP;
1796
1797	/*
1798	* Quotes are not required, but if they exist then we need
1799	* to read them till we hit a matching one.
1800	*/
1801	if (str[i] == '\'' || str[i] == '"')
1802	q = str[i];
1803	else
1804	q = 0;
1805
1806	for (i++; str[i]; i++) {
1807	if (q && str[i] == q)
1808	break;
1809	if (!q && (str[i] == ')' || str[i] == '&' ||
1810	str[i] == '|'))
1811	break;
1812	}
1813	/* Skip quotes */
1814	if (q)
1815	s++;
1816	len = i - s;
1817	if (len >= MAX_FILTER_STR_VAL) {
1818	parse_error(pe, err: FILT_ERR_OPERAND_TOO_LONG, pos: pos + i);
1819	goto err_free;
1820	}
1821
1822	pred->regex = kzalloc(sizeof(*pred->regex), GFP_KERNEL);
1823	if (!pred->regex)
1824	goto err_mem;
1825	pred->regex->len = len;
1826	memcpy(pred->regex->pattern, str + s, len);
1827	pred->regex->pattern[len] = 0;
1828
1829	} else if (!strncmp(str + i, "CPUS", 4)) {
1830	unsigned int maskstart;
1831	bool single;
1832	char *tmp;
1833
1834	switch (field->filter_type) {
1835	case FILTER_CPUMASK:
1836	case FILTER_CPU:
1837	case FILTER_OTHER:
1838	break;
1839	default:
1840	parse_error(pe, err: FILT_ERR_ILLEGAL_FIELD_OP, pos: pos + i);
1841	goto err_free;
1842	}
1843
1844	switch (op) {
1845	case OP_EQ:
1846	case OP_NE:
1847	case OP_BAND:
1848	break;
1849	default:
1850	parse_error(pe, err: FILT_ERR_ILLEGAL_FIELD_OP, pos: pos + i);
1851	goto err_free;
1852	}
1853
1854	/* Skip CPUS */
1855	i += 4;
1856	if (str[i++] != '{') {
1857	parse_error(pe, err: FILT_ERR_MISSING_BRACE_OPEN, pos: pos + i);
1858	goto err_free;
1859	}
1860	maskstart = i;
1861
1862	/* Walk the cpulist until closing } */
1863	for (; str[i] && str[i] != '}'; i++)
1864	;
1865
1866	if (str[i] != '}') {
1867	parse_error(pe, err: FILT_ERR_MISSING_BRACE_CLOSE, pos: pos + i);
1868	goto err_free;
1869	}
1870
1871	if (maskstart == i) {
1872	parse_error(pe, err: FILT_ERR_INVALID_CPULIST, pos: pos + i);
1873	goto err_free;
1874	}
1875
1876	/* Copy the cpulist between { and } */
1877	tmp = kmalloc((i - maskstart) + 1, GFP_KERNEL);
1878	if (!tmp)
1879	goto err_mem;
1880
1881	strscpy(tmp, str + maskstart, (i - maskstart) + 1);
1882	pred->mask = kzalloc(cpumask_size(), GFP_KERNEL);
1883	if (!pred->mask) {
1884	kfree(objp: tmp);
1885	goto err_mem;
1886	}
1887
1888	/* Now parse it */
1889	if (cpulist_parse(buf: tmp, dstp: pred->mask)) {
1890	kfree(objp: tmp);
1891	parse_error(pe, err: FILT_ERR_INVALID_CPULIST, pos: pos + i);
1892	goto err_free;
1893	}
1894	kfree(objp: tmp);
1895
1896	/* Move along */
1897	i++;
1898
1899	/*
1900	* Optimisation: if the user-provided mask has a weight of one
1901	* then we can treat it as a scalar input.
1902	*/
1903	single = cpumask_weight(srcp: pred->mask) == 1;
1904	if (single) {
1905	pred->val = cpumask_first(srcp: pred->mask);
1906	kfree(objp: pred->mask);
1907	pred->mask = NULL;
1908	}
1909
1910	if (field->filter_type == FILTER_CPUMASK) {
1911	pred->fn_num = single ?
1912	FILTER_PRED_FN_CPUMASK_CPU :
1913	FILTER_PRED_FN_CPUMASK;
1914	} else if (field->filter_type == FILTER_CPU) {
1915	if (single) {
1916	if (pred->op == OP_BAND)
1917	pred->op = OP_EQ;
1918
1919	pred->fn_num = FILTER_PRED_FN_CPU;
1920	} else {
1921	pred->fn_num = FILTER_PRED_FN_CPU_CPUMASK;
1922	}
1923	} else if (single) {
1924	if (pred->op == OP_BAND)
1925	pred->op = OP_EQ;
1926
1927	pred->fn_num = select_comparison_fn(op: pred->op, field_size: field->size, field_is_signed: false);
1928	if (pred->op == OP_NE)
1929	pred->not = 1;
1930	} else {
1931	switch (field->size) {
1932	case 8:
1933	pred->fn_num = FILTER_PRED_FN_64_CPUMASK;
1934	break;
1935	case 4:
1936	pred->fn_num = FILTER_PRED_FN_32_CPUMASK;
1937	break;
1938	case 2:
1939	pred->fn_num = FILTER_PRED_FN_16_CPUMASK;
1940	break;
1941	case 1:
1942	pred->fn_num = FILTER_PRED_FN_8_CPUMASK;
1943	break;
1944	}
1945	}
1946
1947	/* This is either a string, or an integer */
1948	} else if (str[i] == '\'' || str[i] == '"') {
1949	char q = str[i];
1950
1951	/* Make sure the op is OK for strings */
1952	switch (op) {
1953	case OP_NE:
1954	pred->not = 1;
1955	fallthrough;
1956	case OP_GLOB:
1957	case OP_EQ:
1958	break;
1959	default:
1960	parse_error(pe, err: FILT_ERR_ILLEGAL_FIELD_OP, pos: pos + i);
1961	goto err_free;
1962	}
1963
1964	/* Make sure the field is OK for strings */
1965	if (!is_string_field(field)) {
1966	parse_error(pe, err: FILT_ERR_EXPECT_DIGIT, pos: pos + i);
1967	goto err_free;
1968	}
1969
1970	for (i++; str[i]; i++) {
1971	if (str[i] == q)
1972	break;
1973	}
1974	if (!str[i]) {
1975	parse_error(pe, err: FILT_ERR_MISSING_QUOTE, pos: pos + i);
1976	goto err_free;
1977	}
1978
1979	/* Skip quotes */
1980	s++;
1981	len = i - s;
1982	if (len >= MAX_FILTER_STR_VAL) {
1983	parse_error(pe, err: FILT_ERR_OPERAND_TOO_LONG, pos: pos + i);
1984	goto err_free;
1985	}
1986
1987	pred->regex = kzalloc(sizeof(*pred->regex), GFP_KERNEL);
1988	if (!pred->regex)
1989	goto err_mem;
1990	pred->regex->len = len;
1991	memcpy(pred->regex->pattern, str + s, len);
1992	pred->regex->pattern[len] = 0;
1993
1994	filter_build_regex(pred);
1995
1996	if (field->filter_type == FILTER_COMM) {
1997	pred->fn_num = FILTER_PRED_FN_COMM;
1998
1999	} else if (field->filter_type == FILTER_STATIC_STRING) {
2000	pred->fn_num = FILTER_PRED_FN_STRING;
2001	pred->regex->field_len = field->size;
2002
2003	} else if (field->filter_type == FILTER_DYN_STRING) {
2004	pred->fn_num = FILTER_PRED_FN_STRLOC;
2005	} else if (field->filter_type == FILTER_RDYN_STRING)
2006	pred->fn_num = FILTER_PRED_FN_STRRELLOC;
2007	else {
2008
2009	if (!ustring_per_cpu) {
2010	/* Once allocated, keep it around for good */
2011	ustring_per_cpu = alloc_percpu(struct ustring_buffer);
2012	if (!ustring_per_cpu)
2013	goto err_mem;
2014	}
2015
2016	if (ustring)
2017	pred->fn_num = FILTER_PRED_FN_PCHAR_USER;
2018	else
2019	pred->fn_num = FILTER_PRED_FN_PCHAR;
2020	}
2021	/* go past the last quote */
2022	i++;
2023
2024	} else if (isdigit(c: str[i]) || str[i] == '-') {
2025
2026	/* Make sure the field is not a string */
2027	if (is_string_field(field)) {
2028	parse_error(pe, err: FILT_ERR_EXPECT_STRING, pos: pos + i);
2029	goto err_free;
2030	}
2031
2032	if (op == OP_GLOB) {
2033	parse_error(pe, err: FILT_ERR_ILLEGAL_FIELD_OP, pos: pos + i);
2034	goto err_free;
2035	}
2036
2037	if (str[i] == '-')
2038	i++;
2039
2040	/* We allow 0xDEADBEEF */
2041	while (isalnum(str[i]))
2042	i++;
2043
2044	len = i - s;
2045	/* 0xfeedfacedeadbeef is 18 chars max */
2046	if (len >= sizeof(num_buf)) {
2047	parse_error(pe, err: FILT_ERR_OPERAND_TOO_LONG, pos: pos + i);
2048	goto err_free;
2049	}
2050
2051	memcpy(num_buf, str + s, len);
2052	num_buf[len] = 0;
2053
2054	/* Make sure it is a value */
2055	if (field->is_signed)
2056	ret = kstrtoll(s: num_buf, base: 0, res: &val);
2057	else
2058	ret = kstrtoull(s: num_buf, base: 0, res: &val);
2059	if (ret) {
2060	parse_error(pe, err: FILT_ERR_ILLEGAL_INTVAL, pos: pos + s);
2061	goto err_free;
2062	}
2063
2064	pred->val = val;
2065
2066	if (field->filter_type == FILTER_CPU)
2067	pred->fn_num = FILTER_PRED_FN_CPU;
2068	else {
2069	pred->fn_num = select_comparison_fn(op: pred->op, field_size: field->size,
2070	field_is_signed: field->is_signed);
2071	if (pred->op == OP_NE)
2072	pred->not = 1;
2073	}
2074
2075	} else {
2076	parse_error(pe, err: FILT_ERR_INVALID_VALUE, pos: pos + i);
2077	goto err_free;
2078	}
2079
2080	*pred_ptr = pred;
2081	return i;
2082
2083	err_free:
2084	free_predicate(pred);
2085	return -EINVAL;
2086	err_mem:
2087	free_predicate(pred);
2088	return -ENOMEM;
2089	}
2090
2091	enum {
2092	TOO_MANY_CLOSE = -1,
2093	TOO_MANY_OPEN = -2,
2094	MISSING_QUOTE = -3,
2095	};
2096
2097	/*
2098	* Read the filter string once to calculate the number of predicates
2099	* as well as how deep the parentheses go.
2100	*
2101	* Returns:
2102	* 0 - everything is fine (err is undefined)
2103	* -1 - too many ')'
2104	* -2 - too many '('
2105	* -3 - No matching quote
2106	*/
2107	static int calc_stack(const char *str, int *parens, int *preds, int *err)
2108	{
2109	bool is_pred = false;
2110	int nr_preds = 0;
2111	int open = 1; /* Count the expression as "(E)" */
2112	int last_quote = 0;
2113	int max_open = 1;
2114	int quote = 0;
2115	int i;
2116
2117	*err = 0;
2118
2119	for (i = 0; str[i]; i++) {
2120	if (isspace(str[i]))
2121	continue;
2122	if (quote) {
2123	if (str[i] == quote)
2124	quote = 0;
2125	continue;
2126	}
2127
2128	switch (str[i]) {
2129	case '\'':
2130	case '"':
2131	quote = str[i];
2132	last_quote = i;
2133	break;
2134	case '|':
2135	case '&':
2136	if (str[i+1] != str[i])
2137	break;
2138	is_pred = false;
2139	continue;
2140	case '(':
2141	is_pred = false;
2142	open++;
2143	if (open > max_open)
2144	max_open = open;
2145	continue;
2146	case ')':
2147	is_pred = false;
2148	if (open == 1) {
2149	*err = i;
2150	return TOO_MANY_CLOSE;
2151	}
2152	open--;
2153	continue;
2154	}
2155	if (!is_pred) {
2156	nr_preds++;
2157	is_pred = true;
2158	}
2159	}
2160
2161	if (quote) {
2162	*err = last_quote;
2163	return MISSING_QUOTE;
2164	}
2165
2166	if (open != 1) {
2167	int level = open;
2168
2169	/* find the bad open */
2170	for (i--; i; i--) {
2171	if (quote) {
2172	if (str[i] == quote)
2173	quote = 0;
2174	continue;
2175	}
2176	switch (str[i]) {
2177	case '(':
2178	if (level == open) {
2179	*err = i;
2180	return TOO_MANY_OPEN;
2181	}
2182	level--;
2183	break;
2184	case ')':
2185	level++;
2186	break;
2187	case '\'':
2188	case '"':
2189	quote = str[i];
2190	break;
2191	}
2192	}
2193	/* First character is the '(' with missing ')' */
2194	*err = 0;
2195	return TOO_MANY_OPEN;
2196	}
2197
2198	/* Set the size of the required stacks */
2199	*parens = max_open;
2200	*preds = nr_preds;
2201	return 0;
2202	}
2203
2204	static int process_preds(struct trace_event_call *call,
2205	const char *filter_string,
2206	struct event_filter *filter,
2207	struct filter_parse_error *pe)
2208	{
2209	struct prog_entry *prog;
2210	int nr_parens;
2211	int nr_preds;
2212	int index;
2213	int ret;
2214
2215	ret = calc_stack(str: filter_string, parens: &nr_parens, preds: &nr_preds, err: &index);
2216	if (ret < 0) {
2217	switch (ret) {
2218	case MISSING_QUOTE:
2219	parse_error(pe, err: FILT_ERR_MISSING_QUOTE, pos: index);
2220	break;
2221	case TOO_MANY_OPEN:
2222	parse_error(pe, err: FILT_ERR_TOO_MANY_OPEN, pos: index);
2223	break;
2224	default:
2225	parse_error(pe, err: FILT_ERR_TOO_MANY_CLOSE, pos: index);
2226	}
2227	return ret;
2228	}
2229
2230	if (!nr_preds)
2231	return -EINVAL;
2232
2233	prog = predicate_parse(str: filter_string, nr_parens, nr_preds,
2234	parse_pred, data: call, pe);
2235	if (IS_ERR(ptr: prog))
2236	return PTR_ERR(ptr: prog);
2237
2238	rcu_assign_pointer(filter->prog, prog);
2239	return 0;
2240	}
2241
2242	static inline void event_set_filtered_flag(struct trace_event_file *file)
2243	{
2244	unsigned long old_flags = file->flags;
2245
2246	file->flags |= EVENT_FILE_FL_FILTERED;
2247
2248	if (old_flags != file->flags)
2249	trace_buffered_event_enable();
2250	}
2251
2252	static int process_system_preds(struct trace_subsystem_dir *dir,
2253	struct trace_array *tr,
2254	struct filter_parse_error *pe,
2255	char *filter_string)
2256	{
2257	struct trace_event_file *file;
2258	struct filter_list *filter_item;
2259	struct event_filter *filter = NULL;
2260	struct filter_head *filter_list;
2261	bool fail = true;
2262	int err;
2263
2264	filter_list = kmalloc(sizeof(*filter_list), GFP_KERNEL);
2265	if (!filter_list)
2266	return -ENOMEM;
2267
2268	INIT_LIST_HEAD(list: &filter_list->list);
2269
2270	list_for_each_entry(file, &tr->events, list) {
2271
2272	if (file->system != dir)
2273	continue;
2274
2275	filter = kzalloc(sizeof(*filter), GFP_KERNEL);
2276	if (!filter)
2277	goto fail_mem;
2278
2279	filter->filter_string = kstrdup(s: filter_string, GFP_KERNEL);
2280	if (!filter->filter_string)
2281	goto fail_mem;
2282
2283	err = process_preds(call: file->event_call, filter_string, filter, pe);
2284	if (err) {
2285	filter_disable(file);
2286	parse_error(pe, err: FILT_ERR_BAD_SUBSYS_FILTER, pos: 0);
2287	append_filter_err(tr, pe, filter);
2288	} else
2289	event_set_filtered_flag(file);
2290
2291
2292	filter_item = kzalloc(sizeof(*filter_item), GFP_KERNEL);
2293	if (!filter_item)
2294	goto fail_mem;
2295
2296	list_add_tail(new: &filter_item->list, head: &filter_list->list);
2297	/*
2298	* Regardless of if this returned an error, we still
2299	* replace the filter for the call.
2300	*/
2301	filter_item->filter = event_filter(file);
2302	event_set_filter(file, filter);
2303	filter = NULL;
2304
2305	fail = false;
2306	}
2307
2308	if (fail)
2309	goto fail;
2310
2311	/*
2312	* The calls can still be using the old filters.
2313	* Do a synchronize_rcu() and to ensure all calls are
2314	* done with them before we free them.
2315	*/
2316	delay_free_filter(head: filter_list);
2317	return 0;
2318	fail:
2319	/* No call succeeded */
2320	free_filter_list(filter_list);
2321	parse_error(pe, err: FILT_ERR_BAD_SUBSYS_FILTER, pos: 0);
2322	return -EINVAL;
2323	fail_mem:
2324	__free_filter(filter);
2325
2326	/* If any call succeeded, we still need to sync */
2327	if (!fail)
2328	delay_free_filter(head: filter_list);
2329	else
2330	free_filter_list(filter_list);
2331
2332	return -ENOMEM;
2333	}
2334
2335	static int create_filter_start(char *filter_string, bool set_str,
2336	struct filter_parse_error **pse,
2337	struct event_filter **filterp)
2338	{
2339	struct event_filter *filter;
2340	struct filter_parse_error *pe = NULL;
2341	int err = 0;
2342
2343	if (WARN_ON_ONCE(*pse || *filterp))
2344	return -EINVAL;
2345
2346	filter = kzalloc(sizeof(*filter), GFP_KERNEL);
2347	if (filter && set_str) {
2348	filter->filter_string = kstrdup(s: filter_string, GFP_KERNEL);
2349	if (!filter->filter_string)
2350	err = -ENOMEM;
2351	}
2352
2353	pe = kzalloc(sizeof(*pe), GFP_KERNEL);
2354
2355	if (!filter || !pe || err) {
2356	kfree(objp: pe);
2357	__free_filter(filter);
2358	return -ENOMEM;
2359	}
2360
2361	/* we're committed to creating a new filter */
2362	*filterp = filter;
2363	*pse = pe;
2364
2365	return 0;
2366	}
2367
2368	static void create_filter_finish(struct filter_parse_error *pe)
2369	{
2370	kfree(objp: pe);
2371	}
2372
2373	/**
2374	* create_filter - create a filter for a trace_event_call
2375	* @tr: the trace array associated with these events
2376	* @call: trace_event_call to create a filter for
2377	* @filter_string: filter string
2378	* @set_str: remember @filter_str and enable detailed error in filter
2379	* @filterp: out param for created filter (always updated on return)
2380	* Must be a pointer that references a NULL pointer.
2381	*
2382	* Creates a filter for @call with @filter_str. If @set_str is %true,
2383	* @filter_str is copied and recorded in the new filter.
2384	*
2385	* On success, returns 0 and *@filterp points to the new filter. On
2386	* failure, returns -errno and *@filterp may point to %NULL or to a new
2387	* filter. In the latter case, the returned filter contains error
2388	* information if @set_str is %true and the caller is responsible for
2389	* freeing it.
2390	*/
2391	static int create_filter(struct trace_array *tr,
2392	struct trace_event_call *call,
2393	char *filter_string, bool set_str,
2394	struct event_filter **filterp)
2395	{
2396	struct filter_parse_error *pe = NULL;
2397	int err;
2398
2399	/* filterp must point to NULL */
2400	if (WARN_ON(*filterp))
2401	*filterp = NULL;
2402
2403	err = create_filter_start(filter_string, set_str, pse: &pe, filterp);
2404	if (err)
2405	return err;
2406
2407	err = process_preds(call, filter_string, filter: *filterp, pe);
2408	if (err && set_str)
2409	append_filter_err(tr, pe, filter: *filterp);
2410	create_filter_finish(pe);
2411
2412	return err;
2413	}
2414
2415	int create_event_filter(struct trace_array *tr,
2416	struct trace_event_call *call,
2417	char *filter_str, bool set_str,
2418	struct event_filter **filterp)
2419	{
2420	return create_filter(tr, call, filter_string: filter_str, set_str, filterp);
2421	}
2422
2423	/**
2424	* create_system_filter - create a filter for an event subsystem
2425	* @dir: the descriptor for the subsystem directory
2426	* @filter_str: filter string
2427	* @filterp: out param for created filter (always updated on return)
2428	*
2429	* Identical to create_filter() except that it creates a subsystem filter
2430	* and always remembers @filter_str.
2431	*/
2432	static int create_system_filter(struct trace_subsystem_dir *dir,
2433	char *filter_str, struct event_filter **filterp)
2434	{
2435	struct filter_parse_error *pe = NULL;
2436	int err;
2437
2438	err = create_filter_start(filter_string: filter_str, set_str: true, pse: &pe, filterp);
2439	if (!err) {
2440	err = process_system_preds(dir, tr: dir->tr, pe, filter_string: filter_str);
2441	if (!err) {
2442	/* System filters just show a default message */
2443	kfree(objp: (*filterp)->filter_string);
2444	(*filterp)->filter_string = NULL;
2445	} else {
2446	append_filter_err(tr: dir->tr, pe, filter: *filterp);
2447	}
2448	}
2449	create_filter_finish(pe);
2450
2451	return err;
2452	}
2453
2454	/* caller must hold event_mutex */
2455	int apply_event_filter(struct trace_event_file *file, char *filter_string)
2456	{
2457	struct trace_event_call *call = file->event_call;
2458	struct event_filter *filter = NULL;
2459	int err;
2460
2461	if (file->flags & EVENT_FILE_FL_FREED)
2462	return -ENODEV;
2463
2464	if (!strcmp(strstrip(str: filter_string), "0")) {
2465	filter_disable(file);
2466	filter = event_filter(file);
2467
2468	if (!filter)
2469	return 0;
2470
2471	event_clear_filter(file);
2472
2473	try_delay_free_filter(filter);
2474
2475	return 0;
2476	}
2477
2478	err = create_filter(tr: file->tr, call, filter_string, set_str: true, filterp: &filter);
2479
2480	/*
2481	* Always swap the call filter with the new filter
2482	* even if there was an error. If there was an error
2483	* in the filter, we disable the filter and show the error
2484	* string
2485	*/
2486	if (filter) {
2487	struct event_filter *tmp;
2488
2489	tmp = event_filter(file);
2490	if (!err)
2491	event_set_filtered_flag(file);
2492	else
2493	filter_disable(file);
2494
2495	event_set_filter(file, filter);
2496
2497	if (tmp)
2498	try_delay_free_filter(filter: tmp);
2499	}
2500
2501	return err;
2502	}
2503
2504	int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
2505	char *filter_string)
2506	{
2507	struct event_subsystem *system = dir->subsystem;
2508	struct trace_array *tr = dir->tr;
2509	struct event_filter *filter = NULL;
2510	int err = 0;
2511
2512	guard(mutex)(T: &event_mutex);
2513
2514	/* Make sure the system still has events */
2515	if (!dir->nr_events)
2516	return -ENODEV;
2517
2518	if (!strcmp(strstrip(str: filter_string), "0")) {
2519	filter_free_subsystem_preds(dir, tr);
2520	remove_filter_string(filter: system->filter);
2521	filter = system->filter;
2522	system->filter = NULL;
2523	/* Ensure all filters are no longer used */
2524	filter_free_subsystem_filters(dir, tr, filter);
2525	return 0;
2526	}
2527
2528	err = create_system_filter(dir, filter_str: filter_string, filterp: &filter);
2529	if (filter) {
2530	/*
2531	* No event actually uses the system filter
2532	* we can free it without synchronize_rcu().
2533	*/
2534	__free_filter(filter: system->filter);
2535	system->filter = filter;
2536	}
2537
2538	return err;
2539	}
2540
2541	#ifdef CONFIG_PERF_EVENTS
2542
2543	void ftrace_profile_free_filter(struct perf_event *event)
2544	{
2545	struct event_filter *filter = event->filter;
2546
2547	event->filter = NULL;
2548	__free_filter(filter);
2549	}
2550
2551	struct function_filter_data {
2552	struct ftrace_ops *ops;
2553	int first_filter;
2554	int first_notrace;
2555	};
2556
2557	#ifdef CONFIG_FUNCTION_TRACER
2558	static char **
2559	ftrace_function_filter_re(char *buf, int len, int *count)
2560	{
2561	char *str, **re;
2562
2563	str = kstrndup(s: buf, len, GFP_KERNEL);
2564	if (!str)
2565	return NULL;
2566
2567	/*
2568	* The argv_split function takes white space
2569	* as a separator, so convert ',' into spaces.
2570	*/
2571	strreplace(str, old: ',', new: ' ');
2572
2573	re = argv_split(GFP_KERNEL, str, argcp: count);
2574	kfree(objp: str);
2575	return re;
2576	}
2577
2578	static int ftrace_function_set_regexp(struct ftrace_ops *ops, int filter,
2579	int reset, char *re, int len)
2580	{
2581	int ret;
2582
2583	if (filter)
2584	ret = ftrace_set_filter(ops, buf: re, len, reset);
2585	else
2586	ret = ftrace_set_notrace(ops, buf: re, len, reset);
2587
2588	return ret;
2589	}
2590
2591	static int __ftrace_function_set_filter(int filter, char *buf, int len,
2592	struct function_filter_data *data)
2593	{
2594	int i, re_cnt, ret = -EINVAL;
2595	int *reset;
2596	char **re;
2597
2598	reset = filter ? &data->first_filter : &data->first_notrace;
2599
2600	/*
2601	* The 'ip' field could have multiple filters set, separated
2602	* either by space or comma. We first cut the filter and apply
2603	* all pieces separately.
2604	*/
2605	re = ftrace_function_filter_re(buf, len, count: &re_cnt);
2606	if (!re)
2607	return -EINVAL;
2608
2609	for (i = 0; i < re_cnt; i++) {
2610	ret = ftrace_function_set_regexp(ops: data->ops, filter, reset: *reset,
2611	re: re[i], strlen(re[i]));
2612	if (ret)
2613	break;
2614
2615	if (*reset)
2616	*reset = 0;
2617	}
2618
2619	argv_free(argv: re);
2620	return ret;
2621	}
2622
2623	static int ftrace_function_check_pred(struct filter_pred *pred)
2624	{
2625	struct ftrace_event_field *field = pred->field;
2626
2627	/*
2628	* Check the predicate for function trace, verify:
2629	* - only '==' and '!=' is used
2630	* - the 'ip' field is used
2631	*/
2632	if ((pred->op != OP_EQ) && (pred->op != OP_NE))
2633	return -EINVAL;
2634
2635	if (strcmp(field->name, "ip"))
2636	return -EINVAL;
2637
2638	return 0;
2639	}
2640
2641	static int ftrace_function_set_filter_pred(struct filter_pred *pred,
2642	struct function_filter_data *data)
2643	{
2644	int ret;
2645
2646	/* Checking the node is valid for function trace. */
2647	ret = ftrace_function_check_pred(pred);
2648	if (ret)
2649	return ret;
2650
2651	return __ftrace_function_set_filter(filter: pred->op == OP_EQ,
2652	buf: pred->regex->pattern,
2653	len: pred->regex->len,
2654	data);
2655	}
2656
2657	static bool is_or(struct prog_entry *prog, int i)
2658	{
2659	int target;
2660
2661	/*
2662	* Only "||" is allowed for function events, thus,
2663	* all true branches should jump to true, and any
2664	* false branch should jump to false.
2665	*/
2666	target = prog[i].target + 1;
2667	/* True and false have NULL preds (all prog entries should jump to one */
2668	if (prog[target].pred)
2669	return false;
2670
2671	/* prog[target].target is 1 for TRUE, 0 for FALSE */
2672	return prog[i].when_to_branch == prog[target].target;
2673	}
2674
2675	static int ftrace_function_set_filter(struct perf_event *event,
2676	struct event_filter *filter)
2677	{
2678	struct prog_entry *prog = rcu_dereference_protected(filter->prog,
2679	lockdep_is_held(&event_mutex));
2680	struct function_filter_data data = {
2681	.first_filter = 1,
2682	.first_notrace = 1,
2683	.ops = &event->ftrace_ops,
2684	};
2685	int i;
2686
2687	for (i = 0; prog[i].pred; i++) {
2688	struct filter_pred *pred = prog[i].pred;
2689
2690	if (!is_or(prog, i))
2691	return -EINVAL;
2692
2693	if (ftrace_function_set_filter_pred(pred, data: &data) < 0)
2694	return -EINVAL;
2695	}
2696	return 0;
2697	}
2698	#else
2699	static int ftrace_function_set_filter(struct perf_event *event,
2700	struct event_filter *filter)
2701	{
2702	return -ENODEV;
2703	}
2704	#endif /* CONFIG_FUNCTION_TRACER */
2705
2706	int ftrace_profile_set_filter(struct perf_event *event, int event_id,
2707	char *filter_str)
2708	{
2709	int err;
2710	struct event_filter *filter = NULL;
2711	struct trace_event_call *call;
2712
2713	guard(mutex)(T: &event_mutex);
2714
2715	call = event->tp_event;
2716
2717	if (!call)
2718	return -EINVAL;
2719
2720	if (event->filter)
2721	return -EEXIST;
2722
2723	err = create_filter(NULL, call, filter_string: filter_str, set_str: false, filterp: &filter);
2724	if (err)
2725	goto free_filter;
2726
2727	if (ftrace_event_is_function(call))
2728	err = ftrace_function_set_filter(event, filter);
2729	else
2730	event->filter = filter;
2731
2732	free_filter:
2733	if (err || ftrace_event_is_function(call))
2734	__free_filter(filter);
2735
2736	return err;
2737	}
2738
2739	#endif /* CONFIG_PERF_EVENTS */
2740
2741	#ifdef CONFIG_FTRACE_STARTUP_TEST
2742
2743	#include <linux/types.h>
2744	#include <linux/tracepoint.h>
2745
2746	#define CREATE_TRACE_POINTS
2747	#include "trace_events_filter_test.h"
2748
2749	#define DATA_REC(m, va, vb, vc, vd, ve, vf, vg, vh, nvisit) \
2750	{ \
2751	.filter = FILTER, \
2752	.rec = { .a = va, .b = vb, .c = vc, .d = vd, \
2753	.e = ve, .f = vf, .g = vg, .h = vh }, \
2754	.match = m, \
2755	.not_visited = nvisit, \
2756	}
2757	#define YES 1
2758	#define NO 0
2759
2760	static struct test_filter_data_t {
2761	char *filter;
2762	struct trace_event_raw_ftrace_test_filter rec;
2763	int match;
2764	char *not_visited;
2765	} test_filter_data[] = {
2766	#define FILTER "a == 1 && b == 1 && c == 1 && d == 1 && " \
2767	"e == 1 && f == 1 && g == 1 && h == 1"
2768	DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, ""),
2769	DATA_REC(NO, 0, 1, 1, 1, 1, 1, 1, 1, "bcdefgh"),
2770	DATA_REC(NO, 1, 1, 1, 1, 1, 1, 1, 0, ""),
2771	#undef FILTER
2772	#define FILTER "a == 1 || b == 1 || c == 1 || d == 1 || " \
2773	"e == 1 || f == 1 || g == 1 || h == 1"
2774	DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 0, ""),
2775	DATA_REC(YES, 0, 0, 0, 0, 0, 0, 0, 1, ""),
2776	DATA_REC(YES, 1, 0, 0, 0, 0, 0, 0, 0, "bcdefgh"),
2777	#undef FILTER
2778	#define FILTER "(a == 1 || b == 1) && (c == 1 || d == 1) && " \
2779	"(e == 1 || f == 1) && (g == 1 || h == 1)"
2780	DATA_REC(NO, 0, 0, 1, 1, 1, 1, 1, 1, "dfh"),
2781	DATA_REC(YES, 0, 1, 0, 1, 0, 1, 0, 1, ""),
2782	DATA_REC(YES, 1, 0, 1, 0, 0, 1, 0, 1, "bd"),
2783	DATA_REC(NO, 1, 0, 1, 0, 0, 1, 0, 0, "bd"),
2784	#undef FILTER
2785	#define FILTER "(a == 1 && b == 1) || (c == 1 && d == 1) || " \
2786	"(e == 1 && f == 1) || (g == 1 && h == 1)"
2787	DATA_REC(YES, 1, 0, 1, 1, 1, 1, 1, 1, "efgh"),
2788	DATA_REC(YES, 0, 0, 0, 0, 0, 0, 1, 1, ""),
2789	DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 1, ""),
2790	#undef FILTER
2791	#define FILTER "(a == 1 && b == 1) && (c == 1 && d == 1) && " \
2792	"(e == 1 && f == 1) || (g == 1 && h == 1)"
2793	DATA_REC(YES, 1, 1, 1, 1, 1, 1, 0, 0, "gh"),
2794	DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 1, ""),
2795	DATA_REC(YES, 1, 1, 1, 1, 1, 0, 1, 1, ""),
2796	#undef FILTER
2797	#define FILTER "((a == 1 || b == 1) || (c == 1 || d == 1) || " \
2798	"(e == 1 || f == 1)) && (g == 1 || h == 1)"
2799	DATA_REC(YES, 1, 1, 1, 1, 1, 1, 0, 1, "bcdef"),
2800	DATA_REC(NO, 0, 0, 0, 0, 0, 0, 0, 0, ""),
2801	DATA_REC(YES, 1, 1, 1, 1, 1, 0, 1, 1, "h"),
2802	#undef FILTER
2803	#define FILTER "((((((((a == 1) && (b == 1)) || (c == 1)) && (d == 1)) || " \
2804	"(e == 1)) && (f == 1)) || (g == 1)) && (h == 1))"
2805	DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, "ceg"),
2806	DATA_REC(NO, 0, 1, 0, 1, 0, 1, 0, 1, ""),
2807	DATA_REC(NO, 1, 0, 1, 0, 1, 0, 1, 0, ""),
2808	#undef FILTER
2809	#define FILTER "((((((((a == 1) || (b == 1)) && (c == 1)) || (d == 1)) && " \
2810	"(e == 1)) || (f == 1)) && (g == 1)) || (h == 1))"
2811	DATA_REC(YES, 1, 1, 1, 1, 1, 1, 1, 1, "bdfh"),
2812	DATA_REC(YES, 0, 1, 0, 1, 0, 1, 0, 1, ""),
2813	DATA_REC(YES, 1, 0, 1, 0, 1, 0, 1, 0, "bdfh"),
2814	};
2815
2816	#undef DATA_REC
2817	#undef FILTER
2818	#undef YES
2819	#undef NO
2820
2821	#define DATA_CNT ARRAY_SIZE(test_filter_data)
2822
2823	static int test_pred_visited;
2824
2825	static int test_pred_visited_fn(struct filter_pred *pred, void *event)
2826	{
2827	struct ftrace_event_field *field = pred->field;
2828
2829	test_pred_visited = 1;
2830	printk(KERN_INFO "\npred visited %s\n", field->name);
2831	return 1;
2832	}
2833
2834	static void update_pred_fn(struct event_filter *filter, char *fields)
2835	{
2836	struct prog_entry *prog = rcu_dereference_protected(filter->prog,
2837	lockdep_is_held(&event_mutex));
2838	int i;
2839
2840	for (i = 0; prog[i].pred; i++) {
2841	struct filter_pred *pred = prog[i].pred;
2842	struct ftrace_event_field *field = pred->field;
2843
2844	WARN_ON_ONCE(pred->fn_num == FILTER_PRED_FN_NOP);
2845
2846	if (!field) {
2847	WARN_ONCE(1, "all leafs should have field defined %d", i);
2848	continue;
2849	}
2850
2851	if (!strchr(fields, *field->name))
2852	continue;
2853
2854	pred->fn_num = FILTER_PRED_TEST_VISITED;
2855	}
2856	}
2857
2858	static __init int ftrace_test_event_filter(void)
2859	{
2860	int i;
2861
2862	printk(KERN_INFO "Testing ftrace filter: ");
2863
2864	for (i = 0; i < DATA_CNT; i++) {
2865	struct event_filter *filter = NULL;
2866	struct test_filter_data_t *d = &test_filter_data[i];
2867	int err;
2868
2869	err = create_filter(NULL, call: &event_ftrace_test_filter,
2870	filter_string: d->filter, set_str: false, filterp: &filter);
2871	if (err) {
2872	printk(KERN_INFO
2873	"Failed to get filter for '%s', err %d\n",
2874	d->filter, err);
2875	__free_filter(filter);
2876	break;
2877	}
2878
2879	/* Needed to dereference filter->prog */
2880	mutex_lock(&event_mutex);
2881	/*
2882	* The preemption disabling is not really needed for self
2883	* tests, but the rcu dereference will complain without it.
2884	*/
2885	preempt_disable();
2886	if (*d->not_visited)
2887	update_pred_fn(filter, fields: d->not_visited);
2888
2889	test_pred_visited = 0;
2890	err = filter_match_preds(filter, &d->rec);
2891	preempt_enable();
2892
2893	mutex_unlock(lock: &event_mutex);
2894
2895	__free_filter(filter);
2896
2897	if (test_pred_visited) {
2898	printk(KERN_INFO
2899	"Failed, unwanted pred visited for filter %s\n",
2900	d->filter);
2901	break;
2902	}
2903
2904	if (err != d->match) {
2905	printk(KERN_INFO
2906	"Failed to match filter '%s', expected %d\n",
2907	d->filter, d->match);
2908	break;
2909	}
2910	}
2911
2912	if (i == DATA_CNT)
2913	printk(KERN_CONT "OK\n");
2914
2915	/* Need to call ftrace_test_filter to prevent a warning */
2916	if (!trace_ftrace_test_filter_enabled())
2917	trace_ftrace_test_filter(a: 1, b: 2, c: 3, d: 4, e: 5, f: 6, g: 7, h: 8);
2918
2919	return 0;
2920	}
2921
2922	late_initcall(ftrace_test_event_filter);
2923
2924	#endif /* CONFIG_FTRACE_STARTUP_TEST */
2925