[deliverable/linux.git] / kernel / trace / trace_events_filter.c

/*
 * trace_events_filter - generic event filtering
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 * Copyright (C) 2009 Tom Zanussi <tzanussi@gmail.com>
 */

#include <linux/debugfs.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/ctype.h>

#include "trace.h"
#include "trace_output.h"

static int filter_pred_64(struct filter_pred *pred, void *event)
{
	u64 *addr = (u64 *)(event + pred->offset);
	u64 val = (u64)pred->val;
	int match;

	match = (val == *addr) ^ pred->not;

	return match;
}

static int filter_pred_32(struct filter_pred *pred, void *event)
{
	u32 *addr = (u32 *)(event + pred->offset);
	u32 val = (u32)pred->val;
	int match;

	match = (val == *addr) ^ pred->not;

	return match;
}

static int filter_pred_16(struct filter_pred *pred, void *event)
{
	u16 *addr = (u16 *)(event + pred->offset);
	u16 val = (u16)pred->val;
	int match;

	match = (val == *addr) ^ pred->not;

	return match;
}

static int filter_pred_8(struct filter_pred *pred, void *event)
{
	u8 *addr = (u8 *)(event + pred->offset);
	u8 val = (u8)pred->val;
	int match;

	match = (val == *addr) ^ pred->not;

	return match;
}

static int filter_pred_string(struct filter_pred *pred, void *event)
{
	char *addr = (char *)(event + pred->offset);
	int cmp, match;

	cmp = strncmp(addr, pred->str_val, pred->str_len);

	match = (!cmp) ^ pred->not;

	return match;
}

static int filter_pred_none(struct filter_pred *pred, void *event)
{
	return 0;
}

/* return 1 if event matches, 0 otherwise (discard) */
int filter_match_preds(struct ftrace_event_call *call, void *rec)
{
	int i, matched, and_failed = 0;
	struct filter_pred *pred;

	for (i = 0; i < call->n_preds; i++) {
		pred = call->preds[i];
		if (and_failed && !pred->or)
			continue;
		matched = pred->fn(pred, rec);
		if (!matched && !pred->or) {
			and_failed = 1;
			continue;
		} else if (matched && pred->or)
			return 1;
	}

	if (and_failed)
		return 0;

	return 1;
}

void filter_print_preds(struct filter_pred **preds, int n_preds,
			struct trace_seq *s)
{
	char *field_name;
	struct filter_pred *pred;
	int i;

	if (!n_preds) {
		trace_seq_printf(s, "none\n");
		return;
	}

	for (i = 0; i < n_preds; i++) {
		pred = preds[i];
		field_name = pred->field_name;
		if (i)
			trace_seq_printf(s, pred->or ? "|| " : "&& ");
		trace_seq_printf(s, "%s ", field_name);
		trace_seq_printf(s, pred->not ? "!= " : "== ");
		if (pred->str_len)
			trace_seq_printf(s, "%s\n", pred->str_val);
		else
			trace_seq_printf(s, "%llu\n", pred->val);
	}
}

static struct ftrace_event_field *
find_event_field(struct ftrace_event_call *call, char *name)
{
	struct ftrace_event_field *field;

	list_for_each_entry(field, &call->fields, link) {
		if (!strcmp(field->name, name))
			return field;
	}

	return NULL;
}

void filter_free_pred(struct filter_pred *pred)
{
	if (!pred)
		return;

	kfree(pred->field_name);
	kfree(pred);
}

static void filter_clear_pred(struct filter_pred *pred)
{
	kfree(pred->field_name);
	pred->field_name = NULL;
	pred->str_len = 0;
}

static int filter_set_pred(struct filter_pred *dest,
			   struct filter_pred *src,
			   filter_pred_fn_t fn)
{
	*dest = *src;
	dest->field_name = kstrdup(src->field_name, GFP_KERNEL);
	if (!dest->field_name)
		return -ENOMEM;
	dest->fn = fn;

	return 0;
}

void filter_disable_preds(struct ftrace_event_call *call)
{
	int i;

	call->n_preds = 0;

	for (i = 0; i < MAX_FILTER_PRED; i++)
		call->preds[i]->fn = filter_pred_none;
}

int init_preds(struct ftrace_event_call *call)
{
	struct filter_pred *pred;
	int i;

	call->n_preds = 0;

	call->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred), GFP_KERNEL);
	if (!call->preds)
		return -ENOMEM;

	for (i = 0; i < MAX_FILTER_PRED; i++) {
		pred = kzalloc(sizeof(*pred), GFP_KERNEL);
		if (!pred)
			goto oom;
		pred->fn = filter_pred_none;
		call->preds[i] = pred;
	}

	return 0;

oom:
	for (i = 0; i < MAX_FILTER_PRED; i++) {
		if (call->preds[i])
			filter_free_pred(call->preds[i]);
	}
	kfree(call->preds);
	call->preds = NULL;

	return -ENOMEM;
}

void filter_free_subsystem_preds(struct event_subsystem *system)
{
	struct ftrace_event_call *call = __start_ftrace_events;
	int i;

	if (system->n_preds) {
		for (i = 0; i < system->n_preds; i++)
			filter_free_pred(system->preds[i]);
		kfree(system->preds);
		system->preds = NULL;
		system->n_preds = 0;
	}

	events_for_each(call) {
		if (!call->define_fields)
			continue;

		if (!strcmp(call->system, system->name))
			filter_disable_preds(call);
	}
}

static int __filter_add_pred(struct ftrace_event_call *call,
			     struct filter_pred *pred,
			     filter_pred_fn_t fn)
{
	int idx, err;

	if (call->n_preds && !pred->compound)
		filter_disable_preds(call);

	if (call->n_preds == MAX_FILTER_PRED)
		return -ENOSPC;

	idx = call->n_preds;
	filter_clear_pred(call->preds[idx]);
	err = filter_set_pred(call->preds[idx], pred, fn);
	if (err)
		return err;

	call->n_preds++;

	return 0;
}

static int is_string_field(const char *type)
{
	if (strchr(type, '[') && strstr(type, "char"))
		return 1;

	return 0;
}

int filter_add_pred(struct ftrace_event_call *call, struct filter_pred *pred)
{
	struct ftrace_event_field *field;
	filter_pred_fn_t fn;

	field = find_event_field(call, pred->field_name);
	if (!field)
		return -EINVAL;

	pred->fn = filter_pred_none;
	pred->offset = field->offset;

	if (is_string_field(field->type)) {
		if (!pred->str_len)
			return -EINVAL;
		fn = filter_pred_string;
		pred->str_len = field->size;
		return __filter_add_pred(call, pred, fn);
	} else {
		if (pred->str_len)
			return -EINVAL;
	}

	switch (field->size) {
	case 8:
		fn = filter_pred_64;
		break;
	case 4:
		fn = filter_pred_32;
		break;
	case 2:
		fn = filter_pred_16;
		break;
	case 1:
		fn = filter_pred_8;
		break;
	default:
		return -EINVAL;
	}

	return __filter_add_pred(call, pred, fn);
}

int filter_add_subsystem_pred(struct event_subsystem *system,
			      struct filter_pred *pred)
{
	struct ftrace_event_call *call = __start_ftrace_events;

	if (system->n_preds && !pred->compound)
		filter_free_subsystem_preds(system);

	if (!system->n_preds) {
		system->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred),
					GFP_KERNEL);
		if (!system->preds)
			return -ENOMEM;
	}

	if (system->n_preds == MAX_FILTER_PRED)
		return -ENOSPC;

	system->preds[system->n_preds] = pred;

	events_for_each(call) {
		int err;

		if (!call->define_fields)
			continue;

		if (strcmp(call->system, system->name))
			continue;

		if (!find_event_field(call, pred->field_name))
			continue;

		err = filter_add_pred(call, pred);
		if (err == -ENOMEM) {
			system->preds[system->n_preds] = NULL;
			return err;
		}
	}

	system->n_preds++;

	return 0;
}

int filter_parse(char **pbuf, struct filter_pred *pred)
{
	char *tmp, *tok, *val_str = NULL;
	int tok_n = 0;

	/* field ==/!= number, or/and field ==/!= number, number */
	while ((tok = strsep(pbuf, " \n"))) {
		if (tok_n == 0) {
			if (!strcmp(tok, "0")) {
				pred->clear = 1;
				return 0;
			} else if (!strcmp(tok, "&&")) {
				pred->or = 0;
				pred->compound = 1;
			} else if (!strcmp(tok, "||")) {
				pred->or = 1;
				pred->compound = 1;
			} else
				pred->field_name = tok;
			tok_n = 1;
			continue;
		}
		if (tok_n == 1) {
			if (!pred->field_name)
				pred->field_name = tok;
			else if (!strcmp(tok, "!="))
				pred->not = 1;
			else if (!strcmp(tok, "=="))
				pred->not = 0;
			else {
				pred->field_name = NULL;
				return -EINVAL;
			}
			tok_n = 2;
			continue;
		}
		if (tok_n == 2) {
			if (pred->compound) {
				if (!strcmp(tok, "!="))
					pred->not = 1;
				else if (!strcmp(tok, "=="))
					pred->not = 0;
				else {
					pred->field_name = NULL;
					return -EINVAL;
				}
			} else {
				val_str = tok;
				break; /* done */
			}
			tok_n = 3;
			continue;
		}
		if (tok_n == 3) {
			val_str = tok;
			break; /* done */
		}
	}

	if (!val_str || !strlen(val_str)
	    || strlen(val_str) >= MAX_FILTER_STR_VAL) {
		pred->field_name = NULL;
		return -EINVAL;
	}

	pred->field_name = kstrdup(pred->field_name, GFP_KERNEL);
	if (!pred->field_name)
		return -ENOMEM;

	pred->str_len = 0;
	pred->val = simple_strtoull(val_str, &tmp, 0);
	if (tmp == val_str) {
		strncpy(pred->str_val, val_str, MAX_FILTER_STR_VAL);
		pred->str_len = strlen(val_str);
		pred->str_val[pred->str_len] = '\0';
	} else if (*tmp != '\0')
		return -EINVAL;

	return 0;
}
Commit	Line	Data
7ce7e424 TZ	1	/*
	2	* trace_events_filter - generic event filtering
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License as published by
	6	* the Free Software Foundation; either version 2 of the License, or
	7	* (at your option) any later version.
	8	*
	9	* This program is distributed in the hope that it will be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
	13	*
	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, write to the Free Software
	16	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	17	*
	18	* Copyright (C) 2009 Tom Zanussi <tzanussi@gmail.com>
	19	*/
	20
	21	#include <linux/debugfs.h>
	22	#include <linux/uaccess.h>
	23	#include <linux/module.h>
	24	#include <linux/ctype.h>
	25
	26	#include "trace.h"
4bda2d51	27	#include "trace_output.h"
7ce7e424 TZ	28
	29	static int filter_pred_64(struct filter_pred pred, void event)
	30	{
	31	u64 addr = (u64 )(event + pred->offset);
	32	u64 val = (u64)pred->val;
	33	int match;
	34
	35	match = (val == *addr) ^ pred->not;
	36
	37	return match;
	38	}
	39
	40	static int filter_pred_32(struct filter_pred pred, void event)
	41	{
	42	u32 addr = (u32 )(event + pred->offset);
	43	u32 val = (u32)pred->val;
	44	int match;
	45
	46	match = (val == *addr) ^ pred->not;
	47
	48	return match;
	49	}
	50
	51	static int filter_pred_16(struct filter_pred pred, void event)
	52	{
	53	u16 addr = (u16 )(event + pred->offset);
	54	u16 val = (u16)pred->val;
	55	int match;
	56
	57	match = (val == *addr) ^ pred->not;
	58
	59	return match;
	60	}
	61
	62	static int filter_pred_8(struct filter_pred pred, void event)
	63	{
	64	u8 addr = (u8 )(event + pred->offset);
	65	u8 val = (u8)pred->val;
	66	int match;
	67
	68	match = (val == *addr) ^ pred->not;
	69
	70	return match;
	71	}
	72
	73	static int filter_pred_string(struct filter_pred pred, void event)
	74	{
	75	char addr = (char )(event + pred->offset);
	76	int cmp, match;
	77
	78	cmp = strncmp(addr, pred->str_val, pred->str_len);
	79
	80	match = (!cmp) ^ pred->not;
	81
	82	return match;
	83	}
	84
0a19e53c TZ	85	static int filter_pred_none(struct filter_pred pred, void event)
	86	{
	87	return 0;
	88	}
	89
7ce7e424 TZ	90	/* return 1 if event matches, 0 otherwise (discard) */
	91	int filter_match_preds(struct ftrace_event_call call, void rec)
	92	{
	93	int i, matched, and_failed = 0;
	94	struct filter_pred *pred;
	95
0a19e53c TZ	96	for (i = 0; i < call->n_preds; i++) {
	97	pred = call->preds[i];
	98	if (and_failed && !pred->or)
	99	continue;
	100	matched = pred->fn(pred, rec);
	101	if (!matched && !pred->or) {
	102	and_failed = 1;
	103	continue;
	104	} else if (matched && pred->or)
	105	return 1;
7ce7e424 TZ	106	}
	107
	108	if (and_failed)
	109	return 0;
	110
	111	return 1;
	112	}
	113
0a19e53c TZ	114	void filter_print_preds(struct filter_pred **preds, int n_preds,
0a19e53c TZ	115	struct trace_seq *s)
7ce7e424	116	{
7ce7e424 TZ	117	char *field_name;
	118	struct filter_pred *pred;
	119	int i;
	120
0a19e53c	121	if (!n_preds) {
4bda2d51 TZ	122	trace_seq_printf(s, "none\n");
4bda2d51 TZ	123	return;
7ce7e424 TZ	124	}
7ce7e424 TZ	125
0a19e53c TZ	126	for (i = 0; i < n_preds; i++) {
	127	pred = preds[i];
	128	field_name = pred->field_name;
	129	if (i)
	130	trace_seq_printf(s, pred->or ? "\|\| " : "&& ");
	131	trace_seq_printf(s, "%s ", field_name);
	132	trace_seq_printf(s, pred->not ? "!= " : "== ");
	133	if (pred->str_len)
	134	trace_seq_printf(s, "%s\n", pred->str_val);
	135	else
	136	trace_seq_printf(s, "%llu\n", pred->val);
7ce7e424	137	}
7ce7e424 TZ	138	}
	139
	140	static struct ftrace_event_field *
	141	find_event_field(struct ftrace_event_call call, char name)
	142	{
1fc2d5c1	143	struct ftrace_event_field *field;
7ce7e424	144
1fc2d5c1	145	list_for_each_entry(field, &call->fields, link) {
7ce7e424 TZ	146	if (!strcmp(field->name, name))
	147	return field;
	148	}
	149
	150	return NULL;
	151	}
	152
	153	void filter_free_pred(struct filter_pred *pred)
	154	{
	155	if (!pred)
	156	return;
	157
	158	kfree(pred->field_name);
7ce7e424 TZ	159	kfree(pred);
	160	}
	161
0a19e53c TZ	162	static void filter_clear_pred(struct filter_pred *pred)
	163	{
	164	kfree(pred->field_name);
	165	pred->field_name = NULL;
	166	pred->str_len = 0;
	167	}
	168
	169	static int filter_set_pred(struct filter_pred *dest,
	170	struct filter_pred *src,
	171	filter_pred_fn_t fn)
	172	{
	173	dest = src;
	174	dest->field_name = kstrdup(src->field_name, GFP_KERNEL);
	175	if (!dest->field_name)
	176	return -ENOMEM;
	177	dest->fn = fn;
	178
	179	return 0;
	180	}
	181
	182	void filter_disable_preds(struct ftrace_event_call *call)
7ce7e424 TZ	183	{
	184	int i;
	185
0a19e53c TZ	186	call->n_preds = 0;
	187
	188	for (i = 0; i < MAX_FILTER_PRED; i++)
	189	call->preds[i]->fn = filter_pred_none;
	190	}
	191
	192	int init_preds(struct ftrace_event_call *call)
	193	{
	194	struct filter_pred *pred;
	195	int i;
	196
	197	call->n_preds = 0;
	198
	199	call->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred), GFP_KERNEL);
	200	if (!call->preds)
	201	return -ENOMEM;
	202
	203	for (i = 0; i < MAX_FILTER_PRED; i++) {
	204	pred = kzalloc(sizeof(*pred), GFP_KERNEL);
	205	if (!pred)
	206	goto oom;
	207	pred->fn = filter_pred_none;
	208	call->preds[i] = pred;
	209	}
	210
	211	return 0;
	212
	213	oom:
	214	for (i = 0; i < MAX_FILTER_PRED; i++) {
	215	if (call->preds[i])
7ce7e424	216	filter_free_pred(call->preds[i]);
7ce7e424	217	}
0a19e53c TZ	218	kfree(call->preds);
	219	call->preds = NULL;
	220
	221	return -ENOMEM;
7ce7e424 TZ	222	}
7ce7e424 TZ	223
cfb180f3 TZ	224	void filter_free_subsystem_preds(struct event_subsystem *system)
	225	{
	226	struct ftrace_event_call *call = __start_ftrace_events;
	227	int i;
	228
0a19e53c TZ	229	if (system->n_preds) {
0a19e53c TZ	230	for (i = 0; i < system->n_preds; i++)
cfb180f3 TZ	231	filter_free_pred(system->preds[i]);
	232	kfree(system->preds);
	233	system->preds = NULL;
0a19e53c	234	system->n_preds = 0;
cfb180f3 TZ	235	}
	236
	237	events_for_each(call) {
e1112b4d	238	if (!call->define_fields)
cfb180f3 TZ	239	continue;
	240
	241	if (!strcmp(call->system, system->name))
0a19e53c	242	filter_disable_preds(call);
cfb180f3 TZ	243	}
	244	}
	245
7ce7e424	246	static int __filter_add_pred(struct ftrace_event_call *call,
0a19e53c TZ	247	struct filter_pred *pred,
0a19e53c TZ	248	filter_pred_fn_t fn)
7ce7e424	249	{
0a19e53c	250	int idx, err;
7ce7e424	251
0a19e53c TZ	252	if (call->n_preds && !pred->compound)
0a19e53c TZ	253	filter_disable_preds(call);
7ce7e424	254
0a19e53c TZ	255	if (call->n_preds == MAX_FILTER_PRED)
0a19e53c TZ	256	return -ENOSPC;
7ce7e424	257
0a19e53c TZ	258	idx = call->n_preds;
	259	filter_clear_pred(call->preds[idx]);
	260	err = filter_set_pred(call->preds[idx], pred, fn);
	261	if (err)
	262	return err;
	263
	264	call->n_preds++;
7ce7e424	265
0a19e53c	266	return 0;
7ce7e424 TZ	267	}
	268
	269	static int is_string_field(const char *type)
	270	{
	271	if (strchr(type, '[') && strstr(type, "char"))
	272	return 1;
	273
	274	return 0;
	275	}
	276
	277	int filter_add_pred(struct ftrace_event_call call, struct filter_pred pred)
	278	{
	279	struct ftrace_event_field *field;
0a19e53c	280	filter_pred_fn_t fn;
7ce7e424 TZ	281
	282	field = find_event_field(call, pred->field_name);
	283	if (!field)
	284	return -EINVAL;
	285
0a19e53c	286	pred->fn = filter_pred_none;
7ce7e424 TZ	287	pred->offset = field->offset;
	288
	289	if (is_string_field(field->type)) {
0a19e53c	290	if (!pred->str_len)
9f58a159	291	return -EINVAL;
0a19e53c	292	fn = filter_pred_string;
7ce7e424	293	pred->str_len = field->size;
0a19e53c	294	return __filter_add_pred(call, pred, fn);
9f58a159	295	} else {
0a19e53c	296	if (pred->str_len)
9f58a159	297	return -EINVAL;
7ce7e424 TZ	298	}
	299
	300	switch (field->size) {
	301	case 8:
0a19e53c	302	fn = filter_pred_64;
7ce7e424 TZ	303	break;
7ce7e424 TZ	304	case 4:
0a19e53c	305	fn = filter_pred_32;
7ce7e424 TZ	306	break;
7ce7e424 TZ	307	case 2:
0a19e53c	308	fn = filter_pred_16;
7ce7e424 TZ	309	break;
7ce7e424 TZ	310	case 1:
0a19e53c	311	fn = filter_pred_8;
7ce7e424 TZ	312	break;
	313	default:
	314	return -EINVAL;
	315	}
	316
0a19e53c	317	return __filter_add_pred(call, pred, fn);
cfb180f3 TZ	318	}
	319
	320	int filter_add_subsystem_pred(struct event_subsystem *system,
	321	struct filter_pred *pred)
	322	{
	323	struct ftrace_event_call *call = __start_ftrace_events;
cfb180f3	324
0a19e53c	325	if (system->n_preds && !pred->compound)
cfb180f3 TZ	326	filter_free_subsystem_preds(system);
cfb180f3 TZ	327
0a19e53c	328	if (!system->n_preds) {
cfb180f3 TZ	329	system->preds = kzalloc(MAX_FILTER_PRED * sizeof(pred),
	330	GFP_KERNEL);
	331	if (!system->preds)
	332	return -ENOMEM;
	333	}
	334
0a19e53c	335	if (system->n_preds == MAX_FILTER_PRED)
44e9c8b7	336	return -ENOSPC;
c4cff064	337
0a19e53c TZ	338	system->preds[system->n_preds] = pred;
0a19e53c TZ	339
cfb180f3	340	events_for_each(call) {
c4cff064 TZ	341	int err;
c4cff064 TZ	342
e1112b4d	343	if (!call->define_fields)
cfb180f3 TZ	344	continue;
cfb180f3 TZ	345
c4cff064 TZ	346	if (strcmp(call->system, system->name))
	347	continue;
	348
	349	if (!find_event_field(call, pred->field_name))
	350	continue;
	351
0a19e53c TZ	352	err = filter_add_pred(call, pred);
	353	if (err == -ENOMEM) {
	354	system->preds[system->n_preds] = NULL;
	355	return err;
	356	}
cfb180f3 TZ	357	}
cfb180f3 TZ	358
0a19e53c	359	system->n_preds++;
c4cff064	360
0a19e53c	361	return 0;
cfb180f3 TZ	362	}
cfb180f3 TZ	363
7ce7e424 TZ	364	int filter_parse(char *pbuf, struct filter_pred pred)
	365	{
	366	char tmp, tok, *val_str = NULL;
	367	int tok_n = 0;
	368
	369	/* field ==/!= number, or/and field ==/!= number, number */
	370	while ((tok = strsep(pbuf, " \n"))) {
	371	if (tok_n == 0) {
	372	if (!strcmp(tok, "0")) {
	373	pred->clear = 1;
	374	return 0;
	375	} else if (!strcmp(tok, "&&")) {
	376	pred->or = 0;
	377	pred->compound = 1;
	378	} else if (!strcmp(tok, "\|\|")) {
	379	pred->or = 1;
	380	pred->compound = 1;
	381	} else
	382	pred->field_name = tok;
	383	tok_n = 1;
	384	continue;
	385	}
	386	if (tok_n == 1) {
	387	if (!pred->field_name)
	388	pred->field_name = tok;
	389	else if (!strcmp(tok, "!="))
	390	pred->not = 1;
	391	else if (!strcmp(tok, "=="))
	392	pred->not = 0;
	393	else {
	394	pred->field_name = NULL;
	395	return -EINVAL;
	396	}
	397	tok_n = 2;
	398	continue;
	399	}
	400	if (tok_n == 2) {
	401	if (pred->compound) {
	402	if (!strcmp(tok, "!="))
	403	pred->not = 1;
	404	else if (!strcmp(tok, "=="))
	405	pred->not = 0;
	406	else {
	407	pred->field_name = NULL;
	408	return -EINVAL;
	409	}
	410	} else {
	411	val_str = tok;
	412	break; /* done */
	413	}
	414	tok_n = 3;
	415	continue;
	416	}
	417	if (tok_n == 3) {
	418	val_str = tok;
	419	break; /* done */
	420	}
	421	}
	422
0a19e53c TZ	423	if (!val_str \|\| !strlen(val_str)
0a19e53c TZ	424	\|\| strlen(val_str) >= MAX_FILTER_STR_VAL) {
bcabd91c LZ	425	pred->field_name = NULL;
	426	return -EINVAL;
	427	}
	428
7ce7e424 TZ	429	pred->field_name = kstrdup(pred->field_name, GFP_KERNEL);
	430	if (!pred->field_name)
	431	return -ENOMEM;
	432
0a19e53c	433	pred->str_len = 0;
a3e0ab05	434	pred->val = simple_strtoull(val_str, &tmp, 0);
7ce7e424	435	if (tmp == val_str) {
0a19e53c TZ	436	strncpy(pred->str_val, val_str, MAX_FILTER_STR_VAL);
	437	pred->str_len = strlen(val_str);
	438	pred->str_val[pred->str_len] = '\0';
a3e0ab05 LZ	439	} else if (*tmp != '\0')
a3e0ab05 LZ	440	return -EINVAL;
7ce7e424 TZ	441
	442	return 0;
	443	}
	444
	445