4 * LTTng modules filter code.
6 * Copyright (C) 2010-2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
8 * Permission is hereby granted, free of charge, to any person obtaining a copy
9 * of this software and associated documentation files (the "Software"), to deal
10 * in the Software without restriction, including without limitation the rights
11 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 * copies of the Software, and to permit persons to whom the Software is
13 * furnished to do so, subject to the following conditions:
15 * The above copyright notice and this permission notice shall be included in
16 * all copies or substantial portions of the Software.
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
21 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
27 #include <linux/list.h>
28 #include <linux/slab.h>
30 #include <lttng-filter.h>
32 static const char *opnames
[] = {
33 [ FILTER_OP_UNKNOWN
] = "UNKNOWN",
35 [ FILTER_OP_RETURN
] = "RETURN",
38 [ FILTER_OP_MUL
] = "MUL",
39 [ FILTER_OP_DIV
] = "DIV",
40 [ FILTER_OP_MOD
] = "MOD",
41 [ FILTER_OP_PLUS
] = "PLUS",
42 [ FILTER_OP_MINUS
] = "MINUS",
43 [ FILTER_OP_RSHIFT
] = "RSHIFT",
44 [ FILTER_OP_LSHIFT
] = "LSHIFT",
45 [ FILTER_OP_BIT_AND
] = "BIT_AND",
46 [ FILTER_OP_BIT_OR
] = "BIT_OR",
47 [ FILTER_OP_BIT_XOR
] = "BIT_XOR",
49 /* binary comparators */
50 [ FILTER_OP_EQ
] = "EQ",
51 [ FILTER_OP_NE
] = "NE",
52 [ FILTER_OP_GT
] = "GT",
53 [ FILTER_OP_LT
] = "LT",
54 [ FILTER_OP_GE
] = "GE",
55 [ FILTER_OP_LE
] = "LE",
57 /* string binary comparators */
58 [ FILTER_OP_EQ_STRING
] = "EQ_STRING",
59 [ FILTER_OP_NE_STRING
] = "NE_STRING",
60 [ FILTER_OP_GT_STRING
] = "GT_STRING",
61 [ FILTER_OP_LT_STRING
] = "LT_STRING",
62 [ FILTER_OP_GE_STRING
] = "GE_STRING",
63 [ FILTER_OP_LE_STRING
] = "LE_STRING",
65 /* s64 binary comparators */
66 [ FILTER_OP_EQ_S64
] = "EQ_S64",
67 [ FILTER_OP_NE_S64
] = "NE_S64",
68 [ FILTER_OP_GT_S64
] = "GT_S64",
69 [ FILTER_OP_LT_S64
] = "LT_S64",
70 [ FILTER_OP_GE_S64
] = "GE_S64",
71 [ FILTER_OP_LE_S64
] = "LE_S64",
73 /* double binary comparators */
74 [ FILTER_OP_EQ_DOUBLE
] = "EQ_DOUBLE",
75 [ FILTER_OP_NE_DOUBLE
] = "NE_DOUBLE",
76 [ FILTER_OP_GT_DOUBLE
] = "GT_DOUBLE",
77 [ FILTER_OP_LT_DOUBLE
] = "LT_DOUBLE",
78 [ FILTER_OP_GE_DOUBLE
] = "GE_DOUBLE",
79 [ FILTER_OP_LE_DOUBLE
] = "LE_DOUBLE",
81 /* Mixed S64-double binary comparators */
82 [ FILTER_OP_EQ_DOUBLE_S64
] = "EQ_DOUBLE_S64",
83 [ FILTER_OP_NE_DOUBLE_S64
] = "NE_DOUBLE_S64",
84 [ FILTER_OP_GT_DOUBLE_S64
] = "GT_DOUBLE_S64",
85 [ FILTER_OP_LT_DOUBLE_S64
] = "LT_DOUBLE_S64",
86 [ FILTER_OP_GE_DOUBLE_S64
] = "GE_DOUBLE_S64",
87 [ FILTER_OP_LE_DOUBLE_S64
] = "LE_DOUBLE_S64",
89 [ FILTER_OP_EQ_S64_DOUBLE
] = "EQ_S64_DOUBLE",
90 [ FILTER_OP_NE_S64_DOUBLE
] = "NE_S64_DOUBLE",
91 [ FILTER_OP_GT_S64_DOUBLE
] = "GT_S64_DOUBLE",
92 [ FILTER_OP_LT_S64_DOUBLE
] = "LT_S64_DOUBLE",
93 [ FILTER_OP_GE_S64_DOUBLE
] = "GE_S64_DOUBLE",
94 [ FILTER_OP_LE_S64_DOUBLE
] = "LE_S64_DOUBLE",
97 [ FILTER_OP_UNARY_PLUS
] = "UNARY_PLUS",
98 [ FILTER_OP_UNARY_MINUS
] = "UNARY_MINUS",
99 [ FILTER_OP_UNARY_NOT
] = "UNARY_NOT",
100 [ FILTER_OP_UNARY_PLUS_S64
] = "UNARY_PLUS_S64",
101 [ FILTER_OP_UNARY_MINUS_S64
] = "UNARY_MINUS_S64",
102 [ FILTER_OP_UNARY_NOT_S64
] = "UNARY_NOT_S64",
103 [ FILTER_OP_UNARY_PLUS_DOUBLE
] = "UNARY_PLUS_DOUBLE",
104 [ FILTER_OP_UNARY_MINUS_DOUBLE
] = "UNARY_MINUS_DOUBLE",
105 [ FILTER_OP_UNARY_NOT_DOUBLE
] = "UNARY_NOT_DOUBLE",
108 [ FILTER_OP_AND
] = "AND",
109 [ FILTER_OP_OR
] = "OR",
112 [ FILTER_OP_LOAD_FIELD_REF
] = "LOAD_FIELD_REF",
113 [ FILTER_OP_LOAD_FIELD_REF_STRING
] = "LOAD_FIELD_REF_STRING",
114 [ FILTER_OP_LOAD_FIELD_REF_SEQUENCE
] = "LOAD_FIELD_REF_SEQUENCE",
115 [ FILTER_OP_LOAD_FIELD_REF_S64
] = "LOAD_FIELD_REF_S64",
116 [ FILTER_OP_LOAD_FIELD_REF_DOUBLE
] = "LOAD_FIELD_REF_DOUBLE",
118 /* load from immediate operand */
119 [ FILTER_OP_LOAD_STRING
] = "LOAD_STRING",
120 [ FILTER_OP_LOAD_S64
] = "LOAD_S64",
121 [ FILTER_OP_LOAD_DOUBLE
] = "LOAD_DOUBLE",
124 [ FILTER_OP_CAST_TO_S64
] = "CAST_TO_S64",
125 [ FILTER_OP_CAST_DOUBLE_TO_S64
] = "CAST_DOUBLE_TO_S64",
126 [ FILTER_OP_CAST_NOP
] = "CAST_NOP",
128 /* get context ref */
129 [ FILTER_OP_GET_CONTEXT_REF
] = "GET_CONTEXT_REF",
130 [ FILTER_OP_GET_CONTEXT_REF_STRING
] = "GET_CONTEXT_REF_STRING",
131 [ FILTER_OP_GET_CONTEXT_REF_S64
] = "GET_CONTEXT_REF_S64",
132 [ FILTER_OP_GET_CONTEXT_REF_DOUBLE
] = "GET_CONTEXT_REF_DOUBLE",
134 /* load userspace field ref */
135 [ FILTER_OP_LOAD_FIELD_REF_USER_STRING
] = "LOAD_FIELD_REF_USER_STRING",
136 [ FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE
] = "LOAD_FIELD_REF_USER_SEQUENCE",
139 * load immediate star globbing pattern (literal string)
142 [ FILTER_OP_LOAD_STAR_GLOB_STRING
] = "LOAD_STAR_GLOB_STRING",
144 /* globbing pattern binary operator: apply to */
145 [ FILTER_OP_EQ_STAR_GLOB_STRING
] = "EQ_STAR_GLOB_STRING",
146 [ FILTER_OP_NE_STAR_GLOB_STRING
] = "NE_STAR_GLOB_STRING",
149 * Instructions for recursive traversal through composed types.
151 [ FILTER_OP_GET_CONTEXT_ROOT
] = "GET_CONTEXT_ROOT",
152 [ FILTER_OP_GET_APP_CONTEXT_ROOT
] = "GET_APP_CONTEXT_ROOT",
153 [ FILTER_OP_GET_PAYLOAD_ROOT
] = "GET_PAYLOAD_ROOT",
155 [ FILTER_OP_GET_SYMBOL
] = "GET_SYMBOL",
156 [ FILTER_OP_GET_SYMBOL_FIELD
] = "GET_SYMBOL_FIELD",
157 [ FILTER_OP_GET_INDEX_U16
] = "GET_INDEX_U16",
158 [ FILTER_OP_GET_INDEX_U64
] = "GET_INDEX_U64",
160 [ FILTER_OP_LOAD_FIELD
] = "LOAD_FIELD",
161 [ FILTER_OP_LOAD_FIELD_S8
] = "LOAD_FIELD_S8",
162 [ FILTER_OP_LOAD_FIELD_S16
] = "LOAD_FIELD_S16",
163 [ FILTER_OP_LOAD_FIELD_S32
] = "LOAD_FIELD_S32",
164 [ FILTER_OP_LOAD_FIELD_S64
] = "LOAD_FIELD_S64",
165 [ FILTER_OP_LOAD_FIELD_U8
] = "LOAD_FIELD_U8",
166 [ FILTER_OP_LOAD_FIELD_U16
] = "LOAD_FIELD_U16",
167 [ FILTER_OP_LOAD_FIELD_U32
] = "LOAD_FIELD_U32",
168 [ FILTER_OP_LOAD_FIELD_U64
] = "LOAD_FIELD_U64",
169 [ FILTER_OP_LOAD_FIELD_STRING
] = "LOAD_FIELD_STRING",
170 [ FILTER_OP_LOAD_FIELD_SEQUENCE
] = "LOAD_FIELD_SEQUENCE",
171 [ FILTER_OP_LOAD_FIELD_DOUBLE
] = "LOAD_FIELD_DOUBLE",
174 const char *lttng_filter_print_op(enum filter_op op
)
176 if (op
>= NR_FILTER_OPS
)
183 int apply_field_reloc(struct lttng_event
*event
,
184 struct bytecode_runtime
*runtime
,
185 uint32_t runtime_len
,
186 uint32_t reloc_offset
,
187 const char *field_name
,
188 enum filter_op filter_op
)
190 const struct lttng_event_desc
*desc
;
191 const struct lttng_event_field
*fields
, *field
= NULL
;
192 unsigned int nr_fields
, i
;
194 uint32_t field_offset
= 0;
196 dbg_printk("Apply field reloc: %u %s\n", reloc_offset
, field_name
);
198 /* Lookup event by name */
202 fields
= desc
->fields
;
205 nr_fields
= desc
->nr_fields
;
206 for (i
= 0; i
< nr_fields
; i
++) {
207 if (!strcmp(fields
[i
].name
, field_name
)) {
211 /* compute field offset */
212 switch (fields
[i
].type
.atype
) {
215 field_offset
+= sizeof(int64_t);
219 case atype_array_bitfield
:
220 case atype_sequence_bitfield
:
221 field_offset
+= sizeof(unsigned long);
222 field_offset
+= sizeof(void *);
225 field_offset
+= sizeof(void *);
227 case atype_struct
: /* Unsupported. */
228 case atype_array_compound
: /* Unsupported. */
229 case atype_sequence_compound
: /* Unsupported. */
230 case atype_variant
: /* Unsupported. */
238 /* Check if field offset is too large for 16-bit offset */
239 if (field_offset
> LTTNG_KERNEL_FILTER_BYTECODE_MAX_LEN
- 1)
243 op
= (struct load_op
*) &runtime
->code
[reloc_offset
];
246 case FILTER_OP_LOAD_FIELD_REF
:
248 struct field_ref
*field_ref
;
250 field_ref
= (struct field_ref
*) op
->data
;
251 switch (field
->type
.atype
) {
254 op
->op
= FILTER_OP_LOAD_FIELD_REF_S64
;
259 op
->op
= FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE
;
261 op
->op
= FILTER_OP_LOAD_FIELD_REF_SEQUENCE
;
265 op
->op
= FILTER_OP_LOAD_FIELD_REF_USER_STRING
;
267 op
->op
= FILTER_OP_LOAD_FIELD_REF_STRING
;
269 case atype_struct
: /* Unsupported. */
270 case atype_array_compound
: /* Unsupported. */
271 case atype_sequence_compound
: /* Unsupported. */
272 case atype_variant
: /* Unsupported. */
273 case atype_array_bitfield
: /* Unsupported. */
274 case atype_sequence_bitfield
: /* Unsupported. */
279 field_ref
->offset
= (uint16_t) field_offset
;
289 int apply_context_reloc(struct lttng_event
*event
,
290 struct bytecode_runtime
*runtime
,
291 uint32_t runtime_len
,
292 uint32_t reloc_offset
,
293 const char *context_name
,
294 enum filter_op filter_op
)
297 struct lttng_ctx_field
*ctx_field
;
300 dbg_printk("Apply context reloc: %u %s\n", reloc_offset
, context_name
);
302 /* Get context index */
303 idx
= lttng_get_context_index(lttng_static_ctx
, context_name
);
307 /* Check if idx is too large for 16-bit offset */
308 if (idx
> LTTNG_KERNEL_FILTER_BYTECODE_MAX_LEN
- 1)
311 /* Get context return type */
312 ctx_field
= <tng_static_ctx
->fields
[idx
];
313 op
= (struct load_op
*) &runtime
->code
[reloc_offset
];
316 case FILTER_OP_GET_CONTEXT_REF
:
318 struct field_ref
*field_ref
;
320 field_ref
= (struct field_ref
*) op
->data
;
321 switch (ctx_field
->event_field
.type
.atype
) {
324 op
->op
= FILTER_OP_GET_CONTEXT_REF_S64
;
326 /* Sequence and array supported as string */
330 BUG_ON(ctx_field
->event_field
.user
);
331 op
->op
= FILTER_OP_GET_CONTEXT_REF_STRING
;
333 case atype_struct
: /* Unsupported. */
334 case atype_array_compound
: /* Unsupported. */
335 case atype_sequence_compound
: /* Unsupported. */
336 case atype_variant
: /* Unsupported. */
337 case atype_array_bitfield
: /* Unsupported. */
338 case atype_sequence_bitfield
: /* Unsupported. */
342 /* set offset to context index within channel contexts */
343 field_ref
->offset
= (uint16_t) idx
;
353 int apply_reloc(struct lttng_event
*event
,
354 struct bytecode_runtime
*runtime
,
355 uint32_t runtime_len
,
356 uint32_t reloc_offset
,
361 dbg_printk("Apply reloc: %u %s\n", reloc_offset
, name
);
363 /* Ensure that the reloc is within the code */
364 if (runtime_len
- reloc_offset
< sizeof(uint16_t))
367 op
= (struct load_op
*) &runtime
->code
[reloc_offset
];
369 case FILTER_OP_LOAD_FIELD_REF
:
370 return apply_field_reloc(event
, runtime
, runtime_len
,
371 reloc_offset
, name
, op
->op
);
372 case FILTER_OP_GET_CONTEXT_REF
:
373 return apply_context_reloc(event
, runtime
, runtime_len
,
374 reloc_offset
, name
, op
->op
);
375 case FILTER_OP_GET_SYMBOL
:
376 case FILTER_OP_GET_SYMBOL_FIELD
:
378 * Will be handled by load specialize phase or
379 * dynamically by interpreter.
383 printk(KERN_WARNING
"Unknown reloc op type %u\n", op
->op
);
390 int bytecode_is_linked(struct lttng_filter_bytecode_node
*filter_bytecode
,
391 struct lttng_event
*event
)
393 struct lttng_bytecode_runtime
*bc_runtime
;
395 list_for_each_entry(bc_runtime
,
396 &event
->bytecode_runtime_head
, node
) {
397 if (bc_runtime
->bc
== filter_bytecode
)
404 * Take a bytecode with reloc table and link it to an event to create a
408 int _lttng_filter_event_link_bytecode(struct lttng_event
*event
,
409 struct lttng_filter_bytecode_node
*filter_bytecode
,
410 struct list_head
*insert_loc
)
412 int ret
, offset
, next_offset
;
413 struct bytecode_runtime
*runtime
= NULL
;
414 size_t runtime_alloc_len
;
416 if (!filter_bytecode
)
418 /* Bytecode already linked */
419 if (bytecode_is_linked(filter_bytecode
, event
))
422 dbg_printk("Linking...\n");
424 /* We don't need the reloc table in the runtime */
425 runtime_alloc_len
= sizeof(*runtime
) + filter_bytecode
->bc
.reloc_offset
;
426 runtime
= kzalloc(runtime_alloc_len
, GFP_KERNEL
);
431 runtime
->p
.bc
= filter_bytecode
;
432 runtime
->p
.event
= event
;
433 runtime
->len
= filter_bytecode
->bc
.reloc_offset
;
434 /* copy original bytecode */
435 memcpy(runtime
->code
, filter_bytecode
->bc
.data
, runtime
->len
);
437 * apply relocs. Those are a uint16_t (offset in bytecode)
438 * followed by a string (field name).
440 for (offset
= filter_bytecode
->bc
.reloc_offset
;
441 offset
< filter_bytecode
->bc
.len
;
442 offset
= next_offset
) {
443 uint16_t reloc_offset
=
444 *(uint16_t *) &filter_bytecode
->bc
.data
[offset
];
446 (const char *) &filter_bytecode
->bc
.data
[offset
+ sizeof(uint16_t)];
448 ret
= apply_reloc(event
, runtime
, runtime
->len
, reloc_offset
, name
);
452 next_offset
= offset
+ sizeof(uint16_t) + strlen(name
) + 1;
454 /* Validate bytecode */
455 ret
= lttng_filter_validate_bytecode(runtime
);
459 /* Specialize bytecode */
460 ret
= lttng_filter_specialize_bytecode(event
, runtime
);
464 runtime
->p
.filter
= lttng_filter_interpret_bytecode
;
465 runtime
->p
.link_failed
= 0;
466 list_add_rcu(&runtime
->p
.node
, insert_loc
);
467 dbg_printk("Linking successful.\n");
471 runtime
->p
.filter
= lttng_filter_false
;
472 runtime
->p
.link_failed
= 1;
473 list_add_rcu(&runtime
->p
.node
, insert_loc
);
475 dbg_printk("Linking failed.\n");
479 void lttng_filter_sync_state(struct lttng_bytecode_runtime
*runtime
)
481 struct lttng_filter_bytecode_node
*bc
= runtime
->bc
;
483 if (!bc
->enabler
->enabled
|| runtime
->link_failed
)
484 runtime
->filter
= lttng_filter_false
;
486 runtime
->filter
= lttng_filter_interpret_bytecode
;
490 * Link bytecode for all enablers referenced by an event.
492 void lttng_enabler_event_link_bytecode(struct lttng_event
*event
,
493 struct lttng_enabler
*enabler
)
495 struct lttng_filter_bytecode_node
*bc
;
496 struct lttng_bytecode_runtime
*runtime
;
498 /* Can only be called for events with desc attached */
499 WARN_ON_ONCE(!event
->desc
);
501 /* Link each bytecode. */
502 list_for_each_entry(bc
, &enabler
->filter_bytecode_head
, node
) {
504 struct list_head
*insert_loc
;
506 list_for_each_entry(runtime
,
507 &event
->bytecode_runtime_head
, node
) {
508 if (runtime
->bc
== bc
) {
513 /* Skip bytecode already linked */
518 * Insert at specified priority (seqnum) in increasing
521 list_for_each_entry_reverse(runtime
,
522 &event
->bytecode_runtime_head
, node
) {
523 if (runtime
->bc
->bc
.seqnum
< bc
->bc
.seqnum
) {
525 insert_loc
= &runtime
->node
;
529 /* Add to head to list */
530 insert_loc
= &event
->bytecode_runtime_head
;
532 dbg_printk("linking bytecode\n");
533 ret
= _lttng_filter_event_link_bytecode(event
, bc
,
536 dbg_printk("[lttng filter] warning: cannot link event bytecode\n");
542 * We own the filter_bytecode if we return success.
544 int lttng_filter_enabler_attach_bytecode(struct lttng_enabler
*enabler
,
545 struct lttng_filter_bytecode_node
*filter_bytecode
)
547 list_add(&filter_bytecode
->node
, &enabler
->filter_bytecode_head
);
551 void lttng_free_enabler_filter_bytecode(struct lttng_enabler
*enabler
)
553 struct lttng_filter_bytecode_node
*filter_bytecode
, *tmp
;
555 list_for_each_entry_safe(filter_bytecode
, tmp
,
556 &enabler
->filter_bytecode_head
, node
) {
557 kfree(filter_bytecode
);
561 void lttng_free_event_filter_runtime(struct lttng_event
*event
)
563 struct bytecode_runtime
*runtime
, *tmp
;
565 list_for_each_entry_safe(runtime
, tmp
,
566 &event
->bytecode_runtime_head
, p
.node
) {
567 kfree(runtime
->data
);