[deliverable/lttng-modules.git] / lttng-filter.c

/* SPDX-License-Identifier: MIT
 *
 * lttng-filter.c
 *
 * LTTng modules filter code.
 *
 * Copyright (C) 2010-2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 */

#include <linux/list.h>
#include <linux/slab.h>

#include <lttng-filter.h>

static const char *opnames[] = {
	[ FILTER_OP_UNKNOWN ] = "UNKNOWN",

	[ FILTER_OP_RETURN ] = "RETURN",

	/* binary */
	[ FILTER_OP_MUL ] = "MUL",
	[ FILTER_OP_DIV ] = "DIV",
	[ FILTER_OP_MOD ] = "MOD",
	[ FILTER_OP_PLUS ] = "PLUS",
	[ FILTER_OP_MINUS ] = "MINUS",
	[ FILTER_OP_BIT_RSHIFT ] = "BIT_RSHIFT",
	[ FILTER_OP_BIT_LSHIFT ] = "BIT_LSHIFT",
	[ FILTER_OP_BIT_AND ] = "BIT_AND",
	[ FILTER_OP_BIT_OR ] = "BIT_OR",
	[ FILTER_OP_BIT_XOR ] = "BIT_XOR",

	/* binary comparators */
	[ FILTER_OP_EQ ] = "EQ",
	[ FILTER_OP_NE ] = "NE",
	[ FILTER_OP_GT ] = "GT",
	[ FILTER_OP_LT ] = "LT",
	[ FILTER_OP_GE ] = "GE",
	[ FILTER_OP_LE ] = "LE",

	/* string binary comparators */
	[ FILTER_OP_EQ_STRING ] = "EQ_STRING",
	[ FILTER_OP_NE_STRING ] = "NE_STRING",
	[ FILTER_OP_GT_STRING ] = "GT_STRING",
	[ FILTER_OP_LT_STRING ] = "LT_STRING",
	[ FILTER_OP_GE_STRING ] = "GE_STRING",
	[ FILTER_OP_LE_STRING ] = "LE_STRING",

	/* s64 binary comparators */
	[ FILTER_OP_EQ_S64 ] = "EQ_S64",
	[ FILTER_OP_NE_S64 ] = "NE_S64",
	[ FILTER_OP_GT_S64 ] = "GT_S64",
	[ FILTER_OP_LT_S64 ] = "LT_S64",
	[ FILTER_OP_GE_S64 ] = "GE_S64",
	[ FILTER_OP_LE_S64 ] = "LE_S64",

	/* double binary comparators */
	[ FILTER_OP_EQ_DOUBLE ] = "EQ_DOUBLE",
	[ FILTER_OP_NE_DOUBLE ] = "NE_DOUBLE",
	[ FILTER_OP_GT_DOUBLE ] = "GT_DOUBLE",
	[ FILTER_OP_LT_DOUBLE ] = "LT_DOUBLE",
	[ FILTER_OP_GE_DOUBLE ] = "GE_DOUBLE",
	[ FILTER_OP_LE_DOUBLE ] = "LE_DOUBLE",

	/* Mixed S64-double binary comparators */
	[ FILTER_OP_EQ_DOUBLE_S64 ] = "EQ_DOUBLE_S64",
	[ FILTER_OP_NE_DOUBLE_S64 ] = "NE_DOUBLE_S64",
	[ FILTER_OP_GT_DOUBLE_S64 ] = "GT_DOUBLE_S64",
	[ FILTER_OP_LT_DOUBLE_S64 ] = "LT_DOUBLE_S64",
	[ FILTER_OP_GE_DOUBLE_S64 ] = "GE_DOUBLE_S64",
	[ FILTER_OP_LE_DOUBLE_S64 ] = "LE_DOUBLE_S64",

	[ FILTER_OP_EQ_S64_DOUBLE ] = "EQ_S64_DOUBLE",
	[ FILTER_OP_NE_S64_DOUBLE ] = "NE_S64_DOUBLE",
	[ FILTER_OP_GT_S64_DOUBLE ] = "GT_S64_DOUBLE",
	[ FILTER_OP_LT_S64_DOUBLE ] = "LT_S64_DOUBLE",
	[ FILTER_OP_GE_S64_DOUBLE ] = "GE_S64_DOUBLE",
	[ FILTER_OP_LE_S64_DOUBLE ] = "LE_S64_DOUBLE",

	/* unary */
	[ FILTER_OP_UNARY_PLUS ] = "UNARY_PLUS",
	[ FILTER_OP_UNARY_MINUS ] = "UNARY_MINUS",
	[ FILTER_OP_UNARY_NOT ] = "UNARY_NOT",
	[ FILTER_OP_UNARY_PLUS_S64 ] = "UNARY_PLUS_S64",
	[ FILTER_OP_UNARY_MINUS_S64 ] = "UNARY_MINUS_S64",
	[ FILTER_OP_UNARY_NOT_S64 ] = "UNARY_NOT_S64",
	[ FILTER_OP_UNARY_PLUS_DOUBLE ] = "UNARY_PLUS_DOUBLE",
	[ FILTER_OP_UNARY_MINUS_DOUBLE ] = "UNARY_MINUS_DOUBLE",
	[ FILTER_OP_UNARY_NOT_DOUBLE ] = "UNARY_NOT_DOUBLE",

	/* logical */
	[ FILTER_OP_AND ] = "AND",
	[ FILTER_OP_OR ] = "OR",

	/* load field ref */
	[ FILTER_OP_LOAD_FIELD_REF ] = "LOAD_FIELD_REF",
	[ FILTER_OP_LOAD_FIELD_REF_STRING ] = "LOAD_FIELD_REF_STRING",
	[ FILTER_OP_LOAD_FIELD_REF_SEQUENCE ] = "LOAD_FIELD_REF_SEQUENCE",
	[ FILTER_OP_LOAD_FIELD_REF_S64 ] = "LOAD_FIELD_REF_S64",
	[ FILTER_OP_LOAD_FIELD_REF_DOUBLE ] = "LOAD_FIELD_REF_DOUBLE",

	/* load from immediate operand */
	[ FILTER_OP_LOAD_STRING ] = "LOAD_STRING",
	[ FILTER_OP_LOAD_S64 ] = "LOAD_S64",
	[ FILTER_OP_LOAD_DOUBLE ] = "LOAD_DOUBLE",

	/* cast */
	[ FILTER_OP_CAST_TO_S64 ] = "CAST_TO_S64",
	[ FILTER_OP_CAST_DOUBLE_TO_S64 ] = "CAST_DOUBLE_TO_S64",
	[ FILTER_OP_CAST_NOP ] = "CAST_NOP",

	/* get context ref */
	[ FILTER_OP_GET_CONTEXT_REF ] = "GET_CONTEXT_REF",
	[ FILTER_OP_GET_CONTEXT_REF_STRING ] = "GET_CONTEXT_REF_STRING",
	[ FILTER_OP_GET_CONTEXT_REF_S64 ] = "GET_CONTEXT_REF_S64",
	[ FILTER_OP_GET_CONTEXT_REF_DOUBLE ] = "GET_CONTEXT_REF_DOUBLE",

	/* load userspace field ref */
	[ FILTER_OP_LOAD_FIELD_REF_USER_STRING ] = "LOAD_FIELD_REF_USER_STRING",
	[ FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE ] = "LOAD_FIELD_REF_USER_SEQUENCE",

	/*
	 * load immediate star globbing pattern (literal string)
	 * from immediate.
	 */
	[ FILTER_OP_LOAD_STAR_GLOB_STRING ] = "LOAD_STAR_GLOB_STRING",

	/* globbing pattern binary operator: apply to */
	[ FILTER_OP_EQ_STAR_GLOB_STRING ] = "EQ_STAR_GLOB_STRING",
	[ FILTER_OP_NE_STAR_GLOB_STRING ] = "NE_STAR_GLOB_STRING",

	/*
	 * Instructions for recursive traversal through composed types.
	 */
	[ FILTER_OP_GET_CONTEXT_ROOT ] = "GET_CONTEXT_ROOT",
	[ FILTER_OP_GET_APP_CONTEXT_ROOT ] = "GET_APP_CONTEXT_ROOT",
	[ FILTER_OP_GET_PAYLOAD_ROOT ] = "GET_PAYLOAD_ROOT",

	[ FILTER_OP_GET_SYMBOL ] = "GET_SYMBOL",
	[ FILTER_OP_GET_SYMBOL_FIELD ] = "GET_SYMBOL_FIELD",
	[ FILTER_OP_GET_INDEX_U16 ] = "GET_INDEX_U16",
	[ FILTER_OP_GET_INDEX_U64 ] = "GET_INDEX_U64",

	[ FILTER_OP_LOAD_FIELD ] = "LOAD_FIELD",
	[ FILTER_OP_LOAD_FIELD_S8 ] = "LOAD_FIELD_S8",
	[ FILTER_OP_LOAD_FIELD_S16 ] = "LOAD_FIELD_S16",
	[ FILTER_OP_LOAD_FIELD_S32 ] = "LOAD_FIELD_S32",
	[ FILTER_OP_LOAD_FIELD_S64 ] = "LOAD_FIELD_S64",
	[ FILTER_OP_LOAD_FIELD_U8 ] = "LOAD_FIELD_U8",
	[ FILTER_OP_LOAD_FIELD_U16 ] = "LOAD_FIELD_U16",
	[ FILTER_OP_LOAD_FIELD_U32 ] = "LOAD_FIELD_U32",
	[ FILTER_OP_LOAD_FIELD_U64 ] = "LOAD_FIELD_U64",
	[ FILTER_OP_LOAD_FIELD_STRING ] = "LOAD_FIELD_STRING",
	[ FILTER_OP_LOAD_FIELD_SEQUENCE ] = "LOAD_FIELD_SEQUENCE",
	[ FILTER_OP_LOAD_FIELD_DOUBLE ] = "LOAD_FIELD_DOUBLE",

	[ FILTER_OP_UNARY_BIT_NOT ] = "UNARY_BIT_NOT",

	[ FILTER_OP_RETURN_S64 ] = "RETURN_S64",
};

const char *lttng_filter_print_op(enum filter_op op)
{
	if (op >= NR_FILTER_OPS)
		return "UNKNOWN";
	else
		return opnames[op];
}

static
int apply_field_reloc(const struct lttng_event_desc *event_desc,
		struct bytecode_runtime *runtime,
		uint32_t runtime_len,
		uint32_t reloc_offset,
		const char *field_name,
		enum filter_op filter_op)
{
	const struct lttng_event_field *fields, *field = NULL;
	unsigned int nr_fields, i;
	struct load_op *op;
	uint32_t field_offset = 0;

	dbg_printk("Apply field reloc: %u %s\n", reloc_offset, field_name);

	/* Lookup event by name */
	if (!event_desc)
		return -EINVAL;
	fields = event_desc->fields;
	if (!fields)
		return -EINVAL;
	nr_fields = event_desc->nr_fields;
	for (i = 0; i < nr_fields; i++) {
		if (!strcmp(fields[i].name, field_name)) {
			field = &fields[i];
			break;
		}
		/* compute field offset */
		switch (fields[i].type.atype) {
		case atype_integer:
		case atype_enum:
			field_offset += sizeof(int64_t);
			break;
		case atype_array:
		case atype_sequence:
		case atype_array_bitfield:
		case atype_sequence_bitfield:
			field_offset += sizeof(unsigned long);
			field_offset += sizeof(void *);
			break;
		case atype_string:
			field_offset += sizeof(void *);
			break;
		case atype_struct:		/* Unsupported. */
		case atype_array_compound:	/* Unsupported. */
		case atype_sequence_compound:	/* Unsupported. */
		case atype_variant:		/* Unsupported. */
		default:
			return -EINVAL;
		}
	}
	if (!field)
		return -EINVAL;

	/* Check if field offset is too large for 16-bit offset */
	if (field_offset > LTTNG_KERNEL_FILTER_BYTECODE_MAX_LEN - 1)
		return -EINVAL;

	/* set type */
	op = (struct load_op *) &runtime->code[reloc_offset];

	switch (filter_op) {
	case FILTER_OP_LOAD_FIELD_REF:
	{
		struct field_ref *field_ref;

		field_ref = (struct field_ref *) op->data;
		switch (field->type.atype) {
		case atype_integer:
		case atype_enum:
			op->op = FILTER_OP_LOAD_FIELD_REF_S64;
			break;
		case atype_array:
		case atype_sequence:
			if (field->user)
				op->op = FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE;
			else
				op->op = FILTER_OP_LOAD_FIELD_REF_SEQUENCE;
			break;
		case atype_string:
			if (field->user)
				op->op = FILTER_OP_LOAD_FIELD_REF_USER_STRING;
			else
				op->op = FILTER_OP_LOAD_FIELD_REF_STRING;
			break;
		case atype_struct:		/* Unsupported. */
		case atype_array_compound:	/* Unsupported. */
		case atype_sequence_compound:	/* Unsupported. */
		case atype_variant:		/* Unsupported. */
		case atype_array_bitfield:	/* Unsupported. */
		case atype_sequence_bitfield:	/* Unsupported. */
		default:
			return -EINVAL;
		}
		/* set offset */
		field_ref->offset = (uint16_t) field_offset;
		break;
	}
	default:
		return -EINVAL;
	}
	return 0;
}

static
int apply_context_reloc(struct bytecode_runtime *runtime,
		uint32_t runtime_len,
		uint32_t reloc_offset,
		const char *context_name,
		enum filter_op filter_op)
{
	struct load_op *op;
	struct lttng_ctx_field *ctx_field;
	int idx;

	dbg_printk("Apply context reloc: %u %s\n", reloc_offset, context_name);

	/* Get context index */
	idx = lttng_get_context_index(lttng_static_ctx, context_name);
	if (idx < 0)
		return -ENOENT;

	/* Check if idx is too large for 16-bit offset */
	if (idx > LTTNG_KERNEL_FILTER_BYTECODE_MAX_LEN - 1)
		return -EINVAL;

	/* Get context return type */
	ctx_field = &lttng_static_ctx->fields[idx];
	op = (struct load_op *) &runtime->code[reloc_offset];

	switch (filter_op) {
	case FILTER_OP_GET_CONTEXT_REF:
	{
		struct field_ref *field_ref;

		field_ref = (struct field_ref *) op->data;
		switch (ctx_field->event_field.type.atype) {
		case atype_integer:
		case atype_enum:
			op->op = FILTER_OP_GET_CONTEXT_REF_S64;
			break;
			/* Sequence and array supported as string */
		case atype_string:
		case atype_array:
		case atype_sequence:
			BUG_ON(ctx_field->event_field.user);
			op->op = FILTER_OP_GET_CONTEXT_REF_STRING;
			break;
		case atype_struct:	/* Unsupported. */
		case atype_array_compound:	/* Unsupported. */
		case atype_sequence_compound:	/* Unsupported. */
		case atype_variant:		/* Unsupported. */
		case atype_array_bitfield:	/* Unsupported. */
		case atype_sequence_bitfield:	/* Unsupported. */
		default:
			return -EINVAL;
		}
		/* set offset to context index within channel contexts */
		field_ref->offset = (uint16_t) idx;
		break;
	}
	default:
		return -EINVAL;
	}
	return 0;
}

static
int apply_reloc(const struct lttng_event_desc *event_desc,
		struct bytecode_runtime *runtime,
		uint32_t runtime_len,
		uint32_t reloc_offset,
		const char *name)
{
	struct load_op *op;

	dbg_printk("Apply reloc: %u %s\n", reloc_offset, name);

	/* Ensure that the reloc is within the code */
	if (runtime_len - reloc_offset < sizeof(uint16_t))
		return -EINVAL;

	op = (struct load_op *) &runtime->code[reloc_offset];
	switch (op->op) {
	case FILTER_OP_LOAD_FIELD_REF:
		return apply_field_reloc(event_desc, runtime, runtime_len,
			reloc_offset, name, op->op);
	case FILTER_OP_GET_CONTEXT_REF:
		return apply_context_reloc(runtime, runtime_len,
			reloc_offset, name, op->op);
	case FILTER_OP_GET_SYMBOL:
	case FILTER_OP_GET_SYMBOL_FIELD:
		/*
		 * Will be handled by load specialize phase or
		 * dynamically by interpreter.
		 */
		return 0;
	default:
		printk(KERN_WARNING "Unknown reloc op type %u\n", op->op);
		return -EINVAL;
	}
	return 0;
}

static
int bytecode_is_linked(struct lttng_filter_bytecode_node *filter_bytecode,
		struct list_head *bytecode_runtime_head)
{
	struct lttng_bytecode_runtime *bc_runtime;

	list_for_each_entry(bc_runtime, bytecode_runtime_head, node) {
		if (bc_runtime->bc == filter_bytecode)
			return 1;
	}
	return 0;
}

/*
 * Take a bytecode with reloc table and link it to an event to create a
 * bytecode runtime.
 */
static
int _lttng_filter_link_bytecode(const struct lttng_event_desc *event_desc,
		struct lttng_ctx *ctx,
		struct lttng_filter_bytecode_node *filter_bytecode,
		struct list_head *insert_loc)
{
	int ret, offset, next_offset;
	struct bytecode_runtime *runtime = NULL;
	size_t runtime_alloc_len;

	if (!filter_bytecode)
		return 0;
	/* Bytecode already linked */
	if (bytecode_is_linked(filter_bytecode, insert_loc))
		return 0;

	dbg_printk("Linking...\n");

	/* We don't need the reloc table in the runtime */
	runtime_alloc_len = sizeof(*runtime) + filter_bytecode->bc.reloc_offset;
	runtime = kzalloc(runtime_alloc_len, GFP_KERNEL);
	if (!runtime) {
		ret = -ENOMEM;
		goto alloc_error;
	}
	runtime->p.bc = filter_bytecode;
	runtime->p.ctx = ctx;
	runtime->len = filter_bytecode->bc.reloc_offset;
	/* copy original bytecode */
	memcpy(runtime->code, filter_bytecode->bc.data, runtime->len);
	/*
	 * apply relocs. Those are a uint16_t (offset in bytecode)
	 * followed by a string (field name).
	 */
	for (offset = filter_bytecode->bc.reloc_offset;
			offset < filter_bytecode->bc.len;
			offset = next_offset) {
		uint16_t reloc_offset =
			*(uint16_t *) &filter_bytecode->bc.data[offset];
		const char *name =
			(const char *) &filter_bytecode->bc.data[offset + sizeof(uint16_t)];

		ret = apply_reloc(event_desc, runtime, runtime->len, reloc_offset, name);
		if (ret) {
			goto link_error;
		}
		next_offset = offset + sizeof(uint16_t) + strlen(name) + 1;
	}
	/* Validate bytecode */
	ret = lttng_filter_validate_bytecode(runtime);
	if (ret) {
		goto link_error;
	}
	/* Specialize bytecode */
	ret = lttng_filter_specialize_bytecode(event_desc, runtime);
	if (ret) {
		goto link_error;
	}
	runtime->p.filter = lttng_filter_interpret_bytecode;
	runtime->p.link_failed = 0;
	list_add_rcu(&runtime->p.node, insert_loc);
	dbg_printk("Linking successful.\n");
	return 0;

link_error:
	runtime->p.filter = lttng_filter_false;
	runtime->p.link_failed = 1;
	list_add_rcu(&runtime->p.node, insert_loc);
alloc_error:
	dbg_printk("Linking failed.\n");
	return ret;
}

void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime)
{
	struct lttng_filter_bytecode_node *bc = runtime->bc;

	if (!bc->enabler->enabled || runtime->link_failed)
		runtime->filter = lttng_filter_false;
	else
		runtime->filter = lttng_filter_interpret_bytecode;
}

/*
 * Link bytecode for all enablers referenced by an event.
 */
void lttng_enabler_link_bytecode(const struct lttng_event_desc *event_desc,
		struct lttng_ctx *ctx,
		struct list_head *bytecode_runtime_head,
		struct lttng_enabler *enabler)
{
	struct lttng_filter_bytecode_node *bc;
	struct lttng_bytecode_runtime *runtime;

	/* Can only be called for events with desc attached */
	WARN_ON_ONCE(!event_desc);

	/* Link each bytecode. */
	list_for_each_entry(bc, &enabler->filter_bytecode_head, node) {
		int found = 0, ret;
		struct list_head *insert_loc;

		list_for_each_entry(runtime,
				bytecode_runtime_head, node) {
			if (runtime->bc == bc) {
				found = 1;
				break;
			}
		}
		/* Skip bytecode already linked */
		if (found)
			continue;

		/*
		 * Insert at specified priority (seqnum) in increasing
		 * order.
		 */
		list_for_each_entry_reverse(runtime,
				bytecode_runtime_head, node) {
			if (runtime->bc->bc.seqnum < bc->bc.seqnum) {
				/* insert here */
				insert_loc = &runtime->node;
				goto add_within;
			}
		}
		/* Add to head to list */
		insert_loc = bytecode_runtime_head;
	add_within:
		dbg_printk("linking bytecode\n");
		ret = _lttng_filter_link_bytecode(event_desc, ctx, bc,
			insert_loc);
		if (ret) {
			dbg_printk("[lttng filter] warning: cannot link event bytecode\n");
		}
	}
}

/*
 * We own the filter_bytecode if we return success.
 */
int lttng_filter_enabler_attach_bytecode(struct lttng_enabler *enabler,
		struct lttng_filter_bytecode_node *filter_bytecode)
{
	list_add(&filter_bytecode->node, &enabler->filter_bytecode_head);
	return 0;
}

void lttng_free_enabler_filter_bytecode(struct lttng_enabler *enabler)
{
	struct lttng_filter_bytecode_node *filter_bytecode, *tmp;

	list_for_each_entry_safe(filter_bytecode, tmp,
			&enabler->filter_bytecode_head, node) {
		kfree(filter_bytecode);
	}
}

void lttng_free_event_filter_runtime(struct lttng_event *event)
{
	struct bytecode_runtime *runtime, *tmp;

	list_for_each_entry_safe(runtime, tmp,
			&event->bytecode_runtime_head, p.node) {
		kfree(runtime->data);
		kfree(runtime);
	}
}
Commit	Line	Data
9f36eaed MJ	1	/* SPDX-License-Identifier: MIT
9f36eaed MJ	2	*
07dfc1d0 MD	3	* lttng-filter.c
	4	*
	5	* LTTng modules filter code.
	6	*
bbf3aef5	7	* Copyright (C) 2010-2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
07dfc1d0 MD	8	*/
	9
	10	#include <linux/list.h>
	11	#include <linux/slab.h>
	12
241ae9a8	13	#include <lttng-filter.h>
07dfc1d0 MD	14
	15	static const char *opnames[] = {
	16	[ FILTER_OP_UNKNOWN ] = "UNKNOWN",
	17
	18	[ FILTER_OP_RETURN ] = "RETURN",
	19
	20	/* binary */
	21	[ FILTER_OP_MUL ] = "MUL",
	22	[ FILTER_OP_DIV ] = "DIV",
	23	[ FILTER_OP_MOD ] = "MOD",
	24	[ FILTER_OP_PLUS ] = "PLUS",
	25	[ FILTER_OP_MINUS ] = "MINUS",
e16c054b MD	26	[ FILTER_OP_BIT_RSHIFT ] = "BIT_RSHIFT",
e16c054b MD	27	[ FILTER_OP_BIT_LSHIFT ] = "BIT_LSHIFT",
3834b99f MD	28	[ FILTER_OP_BIT_AND ] = "BIT_AND",
	29	[ FILTER_OP_BIT_OR ] = "BIT_OR",
	30	[ FILTER_OP_BIT_XOR ] = "BIT_XOR",
07dfc1d0 MD	31
	32	/* binary comparators */
	33	[ FILTER_OP_EQ ] = "EQ",
	34	[ FILTER_OP_NE ] = "NE",
	35	[ FILTER_OP_GT ] = "GT",
	36	[ FILTER_OP_LT ] = "LT",
	37	[ FILTER_OP_GE ] = "GE",
	38	[ FILTER_OP_LE ] = "LE",
	39
	40	/* string binary comparators */
	41	[ FILTER_OP_EQ_STRING ] = "EQ_STRING",
	42	[ FILTER_OP_NE_STRING ] = "NE_STRING",
	43	[ FILTER_OP_GT_STRING ] = "GT_STRING",
	44	[ FILTER_OP_LT_STRING ] = "LT_STRING",
	45	[ FILTER_OP_GE_STRING ] = "GE_STRING",
	46	[ FILTER_OP_LE_STRING ] = "LE_STRING",
	47
	48	/* s64 binary comparators */
	49	[ FILTER_OP_EQ_S64 ] = "EQ_S64",
	50	[ FILTER_OP_NE_S64 ] = "NE_S64",
	51	[ FILTER_OP_GT_S64 ] = "GT_S64",
	52	[ FILTER_OP_LT_S64 ] = "LT_S64",
	53	[ FILTER_OP_GE_S64 ] = "GE_S64",
	54	[ FILTER_OP_LE_S64 ] = "LE_S64",
	55
	56	/* double binary comparators */
	57	[ FILTER_OP_EQ_DOUBLE ] = "EQ_DOUBLE",
	58	[ FILTER_OP_NE_DOUBLE ] = "NE_DOUBLE",
	59	[ FILTER_OP_GT_DOUBLE ] = "GT_DOUBLE",
	60	[ FILTER_OP_LT_DOUBLE ] = "LT_DOUBLE",
	61	[ FILTER_OP_GE_DOUBLE ] = "GE_DOUBLE",
	62	[ FILTER_OP_LE_DOUBLE ] = "LE_DOUBLE",
	63
	64	/* Mixed S64-double binary comparators */
	65	[ FILTER_OP_EQ_DOUBLE_S64 ] = "EQ_DOUBLE_S64",
	66	[ FILTER_OP_NE_DOUBLE_S64 ] = "NE_DOUBLE_S64",
	67	[ FILTER_OP_GT_DOUBLE_S64 ] = "GT_DOUBLE_S64",
	68	[ FILTER_OP_LT_DOUBLE_S64 ] = "LT_DOUBLE_S64",
	69	[ FILTER_OP_GE_DOUBLE_S64 ] = "GE_DOUBLE_S64",
	70	[ FILTER_OP_LE_DOUBLE_S64 ] = "LE_DOUBLE_S64",
	71
	72	[ FILTER_OP_EQ_S64_DOUBLE ] = "EQ_S64_DOUBLE",
	73	[ FILTER_OP_NE_S64_DOUBLE ] = "NE_S64_DOUBLE",
	74	[ FILTER_OP_GT_S64_DOUBLE ] = "GT_S64_DOUBLE",
	75	[ FILTER_OP_LT_S64_DOUBLE ] = "LT_S64_DOUBLE",
	76	[ FILTER_OP_GE_S64_DOUBLE ] = "GE_S64_DOUBLE",
	77	[ FILTER_OP_LE_S64_DOUBLE ] = "LE_S64_DOUBLE",
	78
	79	/* unary */
	80	[ FILTER_OP_UNARY_PLUS ] = "UNARY_PLUS",
	81	[ FILTER_OP_UNARY_MINUS ] = "UNARY_MINUS",
	82	[ FILTER_OP_UNARY_NOT ] = "UNARY_NOT",
	83	[ FILTER_OP_UNARY_PLUS_S64 ] = "UNARY_PLUS_S64",
	84	[ FILTER_OP_UNARY_MINUS_S64 ] = "UNARY_MINUS_S64",
	85	[ FILTER_OP_UNARY_NOT_S64 ] = "UNARY_NOT_S64",
	86	[ FILTER_OP_UNARY_PLUS_DOUBLE ] = "UNARY_PLUS_DOUBLE",
	87	[ FILTER_OP_UNARY_MINUS_DOUBLE ] = "UNARY_MINUS_DOUBLE",
	88	[ FILTER_OP_UNARY_NOT_DOUBLE ] = "UNARY_NOT_DOUBLE",
	89
	90	/* logical */
	91	[ FILTER_OP_AND ] = "AND",
	92	[ FILTER_OP_OR ] = "OR",
	93
	94	/* load field ref */
95	[ FILTER_OP_LOAD_FIELD_REF ] = "LOAD_FIELD_REF",
96	[ FILTER_OP_LOAD_FIELD_REF_STRING ] = "LOAD_FIELD_REF_STRING",
97	[ FILTER_OP_LOAD_FIELD_REF_SEQUENCE ] = "LOAD_FIELD_REF_SEQUENCE",
98	[ FILTER_OP_LOAD_FIELD_REF_S64 ] = "LOAD_FIELD_REF_S64",
99	[ FILTER_OP_LOAD_FIELD_REF_DOUBLE ] = "LOAD_FIELD_REF_DOUBLE",
100
101	/* load from immediate operand */
102	[ FILTER_OP_LOAD_STRING ] = "LOAD_STRING",
103	[ FILTER_OP_LOAD_S64 ] = "LOAD_S64",
104	[ FILTER_OP_LOAD_DOUBLE ] = "LOAD_DOUBLE",
105
106	/* cast */
107	[ FILTER_OP_CAST_TO_S64 ] = "CAST_TO_S64",
108	[ FILTER_OP_CAST_DOUBLE_TO_S64 ] = "CAST_DOUBLE_TO_S64",
109	[ FILTER_OP_CAST_NOP ] = "CAST_NOP",
110
111	/* get context ref */
112	[ FILTER_OP_GET_CONTEXT_REF ] = "GET_CONTEXT_REF",
113	[ FILTER_OP_GET_CONTEXT_REF_STRING ] = "GET_CONTEXT_REF_STRING",
114	[ FILTER_OP_GET_CONTEXT_REF_S64 ] = "GET_CONTEXT_REF_S64",
115	[ FILTER_OP_GET_CONTEXT_REF_DOUBLE ] = "GET_CONTEXT_REF_DOUBLE",
f127e61e MD	116
	117	/* load userspace field ref */
	118	[ FILTER_OP_LOAD_FIELD_REF_USER_STRING ] = "LOAD_FIELD_REF_USER_STRING",
	119	[ FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE ] = "LOAD_FIELD_REF_USER_SEQUENCE",
83fb57ab MD	120
	121	/*
	122	* load immediate star globbing pattern (literal string)
	123	* from immediate.
	124	*/
	125	[ FILTER_OP_LOAD_STAR_GLOB_STRING ] = "LOAD_STAR_GLOB_STRING",
	126
	127	/* globbing pattern binary operator: apply to */
	128	[ FILTER_OP_EQ_STAR_GLOB_STRING ] = "EQ_STAR_GLOB_STRING",
	129	[ FILTER_OP_NE_STAR_GLOB_STRING ] = "NE_STAR_GLOB_STRING",
3834b99f MD	130
	131	/*
	132	* Instructions for recursive traversal through composed types.
	133	*/
	134	[ FILTER_OP_GET_CONTEXT_ROOT ] = "GET_CONTEXT_ROOT",
	135	[ FILTER_OP_GET_APP_CONTEXT_ROOT ] = "GET_APP_CONTEXT_ROOT",
	136	[ FILTER_OP_GET_PAYLOAD_ROOT ] = "GET_PAYLOAD_ROOT",
	137
	138	[ FILTER_OP_GET_SYMBOL ] = "GET_SYMBOL",
	139	[ FILTER_OP_GET_SYMBOL_FIELD ] = "GET_SYMBOL_FIELD",
	140	[ FILTER_OP_GET_INDEX_U16 ] = "GET_INDEX_U16",
	141	[ FILTER_OP_GET_INDEX_U64 ] = "GET_INDEX_U64",
	142
	143	[ FILTER_OP_LOAD_FIELD ] = "LOAD_FIELD",
	144	[ FILTER_OP_LOAD_FIELD_S8 ] = "LOAD_FIELD_S8",
	145	[ FILTER_OP_LOAD_FIELD_S16 ] = "LOAD_FIELD_S16",
	146	[ FILTER_OP_LOAD_FIELD_S32 ] = "LOAD_FIELD_S32",
	147	[ FILTER_OP_LOAD_FIELD_S64 ] = "LOAD_FIELD_S64",
	148	[ FILTER_OP_LOAD_FIELD_U8 ] = "LOAD_FIELD_U8",
	149	[ FILTER_OP_LOAD_FIELD_U16 ] = "LOAD_FIELD_U16",
	150	[ FILTER_OP_LOAD_FIELD_U32 ] = "LOAD_FIELD_U32",
	151	[ FILTER_OP_LOAD_FIELD_U64 ] = "LOAD_FIELD_U64",
	152	[ FILTER_OP_LOAD_FIELD_STRING ] = "LOAD_FIELD_STRING",
	153	[ FILTER_OP_LOAD_FIELD_SEQUENCE ] = "LOAD_FIELD_SEQUENCE",
	154	[ FILTER_OP_LOAD_FIELD_DOUBLE ] = "LOAD_FIELD_DOUBLE",
e16c054b MD	155
e16c054b MD	156	[ FILTER_OP_UNARY_BIT_NOT ] = "UNARY_BIT_NOT",
57ba4b41 MD	157
57ba4b41 MD	158	[ FILTER_OP_RETURN_S64 ] = "RETURN_S64",
07dfc1d0 MD	159	};
	160
	161	const char *lttng_filter_print_op(enum filter_op op)
	162	{
	163	if (op >= NR_FILTER_OPS)
	164	return "UNKNOWN";
	165	else
	166	return opnames[op];
	167	}
	168
	169	static
63629d86	170	int apply_field_reloc(const struct lttng_event_desc *event_desc,
07dfc1d0 MD	171	struct bytecode_runtime *runtime,
	172	uint32_t runtime_len,
	173	uint32_t reloc_offset,
3834b99f MD	174	const char *field_name,
3834b99f MD	175	enum filter_op filter_op)
07dfc1d0	176	{
07dfc1d0 MD	177	const struct lttng_event_field fields, field = NULL;
07dfc1d0 MD	178	unsigned int nr_fields, i;
07dfc1d0 MD	179	struct load_op *op;
	180	uint32_t field_offset = 0;
	181
	182	dbg_printk("Apply field reloc: %u %s\n", reloc_offset, field_name);
	183
	184	/* Lookup event by name */
63629d86	185	if (!event_desc)
07dfc1d0	186	return -EINVAL;
63629d86	187	fields = event_desc->fields;
07dfc1d0 MD	188	if (!fields)
07dfc1d0 MD	189	return -EINVAL;
63629d86	190	nr_fields = event_desc->nr_fields;
07dfc1d0 MD	191	for (i = 0; i < nr_fields; i++) {
	192	if (!strcmp(fields[i].name, field_name)) {
	193	field = &fields[i];
	194	break;
	195	}
	196	/* compute field offset */
	197	switch (fields[i].type.atype) {
	198	case atype_integer:
	199	case atype_enum:
	200	field_offset += sizeof(int64_t);
	201	break;
	202	case atype_array:
	203	case atype_sequence:
3834b99f MD	204	case atype_array_bitfield:
3834b99f MD	205	case atype_sequence_bitfield:
07dfc1d0 MD	206	field_offset += sizeof(unsigned long);
	207	field_offset += sizeof(void *);
	208	break;
	209	case atype_string:
	210	field_offset += sizeof(void *);
	211	break;
f513b2bf MD	212	case atype_struct: /* Unsupported. */
	213	case atype_array_compound: /* Unsupported. */
	214	case atype_sequence_compound: /* Unsupported. */
65c85aa6	215	case atype_variant: /* Unsupported. */
07dfc1d0 MD	216	default:
	217	return -EINVAL;
	218	}
	219	}
	220	if (!field)
	221	return -EINVAL;
	222
	223	/* Check if field offset is too large for 16-bit offset */
f127e61e	224	if (field_offset > LTTNG_KERNEL_FILTER_BYTECODE_MAX_LEN - 1)
07dfc1d0 MD	225	return -EINVAL;
	226
	227	/* set type */
3834b99f MD	228	op = (struct load_op *) &runtime->code[reloc_offset];
	229
	230	switch (filter_op) {
	231	case FILTER_OP_LOAD_FIELD_REF:
	232	{
	233	struct field_ref *field_ref;
	234
	235	field_ref = (struct field_ref *) op->data;
	236	switch (field->type.atype) {
	237	case atype_integer:
	238	case atype_enum:
	239	op->op = FILTER_OP_LOAD_FIELD_REF_S64;
	240	break;
	241	case atype_array:
	242	case atype_sequence:
	243	if (field->user)
	244	op->op = FILTER_OP_LOAD_FIELD_REF_USER_SEQUENCE;
	245	else
	246	op->op = FILTER_OP_LOAD_FIELD_REF_SEQUENCE;
	247	break;
	248	case atype_string:
	249	if (field->user)
	250	op->op = FILTER_OP_LOAD_FIELD_REF_USER_STRING;
	251	else
	252	op->op = FILTER_OP_LOAD_FIELD_REF_STRING;
	253	break;
	254	case atype_struct: /* Unsupported. */
	255	case atype_array_compound: /* Unsupported. */
	256	case atype_sequence_compound: /* Unsupported. */
	257	case atype_variant: /* Unsupported. */
	258	case atype_array_bitfield: /* Unsupported. */
	259	case atype_sequence_bitfield: /* Unsupported. */
	260	default:
	261	return -EINVAL;
	262	}
	263	/* set offset */
	264	field_ref->offset = (uint16_t) field_offset;
07dfc1d0	265	break;
3834b99f	266	}
07dfc1d0 MD	267	default:
	268	return -EINVAL;
	269	}
07dfc1d0 MD	270	return 0;
	271	}
	272
	273	static
63629d86	274	int apply_context_reloc(struct bytecode_runtime *runtime,
07dfc1d0 MD	275	uint32_t runtime_len,
07dfc1d0 MD	276	uint32_t reloc_offset,
3834b99f MD	277	const char *context_name,
3834b99f MD	278	enum filter_op filter_op)
07dfc1d0	279	{
07dfc1d0 MD	280	struct load_op *op;
	281	struct lttng_ctx_field *ctx_field;
	282	int idx;
	283
	284	dbg_printk("Apply context reloc: %u %s\n", reloc_offset, context_name);
	285
	286	/* Get context index */
	287	idx = lttng_get_context_index(lttng_static_ctx, context_name);
	288	if (idx < 0)
	289	return -ENOENT;
	290
	291	/* Check if idx is too large for 16-bit offset */
f127e61e	292	if (idx > LTTNG_KERNEL_FILTER_BYTECODE_MAX_LEN - 1)
07dfc1d0 MD	293	return -EINVAL;
	294
	295	/* Get context return type */
	296	ctx_field = &lttng_static_ctx->fields[idx];
3834b99f MD	297	op = (struct load_op *) &runtime->code[reloc_offset];
	298
	299	switch (filter_op) {
	300	case FILTER_OP_GET_CONTEXT_REF:
	301	{
	302	struct field_ref *field_ref;
	303
	304	field_ref = (struct field_ref *) op->data;
	305	switch (ctx_field->event_field.type.atype) {
	306	case atype_integer:
	307	case atype_enum:
	308	op->op = FILTER_OP_GET_CONTEXT_REF_S64;
	309	break;
	310	/* Sequence and array supported as string */
	311	case atype_string:
	312	case atype_array:
	313	case atype_sequence:
	314	BUG_ON(ctx_field->event_field.user);
	315	op->op = FILTER_OP_GET_CONTEXT_REF_STRING;
	316	break;
	317	case atype_struct: /* Unsupported. */
	318	case atype_array_compound: /* Unsupported. */
	319	case atype_sequence_compound: /* Unsupported. */
	320	case atype_variant: /* Unsupported. */
	321	case atype_array_bitfield: /* Unsupported. */
	322	case atype_sequence_bitfield: /* Unsupported. */
	323	default:
	324	return -EINVAL;
	325	}
	326	/* set offset to context index within channel contexts */
	327	field_ref->offset = (uint16_t) idx;
07dfc1d0	328	break;
3834b99f	329	}
07dfc1d0 MD	330	default:
	331	return -EINVAL;
	332	}
07dfc1d0 MD	333	return 0;
	334	}
	335
	336	static
63629d86	337	int apply_reloc(const struct lttng_event_desc *event_desc,
07dfc1d0 MD	338	struct bytecode_runtime *runtime,
	339	uint32_t runtime_len,
	340	uint32_t reloc_offset,
	341	const char *name)
	342	{
	343	struct load_op *op;
	344
	345	dbg_printk("Apply reloc: %u %s\n", reloc_offset, name);
	346
	347	/* Ensure that the reloc is within the code */
	348	if (runtime_len - reloc_offset < sizeof(uint16_t))
	349	return -EINVAL;
	350
3834b99f	351	op = (struct load_op *) &runtime->code[reloc_offset];
07dfc1d0 MD	352	switch (op->op) {
07dfc1d0 MD	353	case FILTER_OP_LOAD_FIELD_REF:
63629d86	354	return apply_field_reloc(event_desc, runtime, runtime_len,
3834b99f	355	reloc_offset, name, op->op);
07dfc1d0	356	case FILTER_OP_GET_CONTEXT_REF:
63629d86	357	return apply_context_reloc(runtime, runtime_len,
3834b99f MD	358	reloc_offset, name, op->op);
	359	case FILTER_OP_GET_SYMBOL:
	360	case FILTER_OP_GET_SYMBOL_FIELD:
	361	/*
	362	* Will be handled by load specialize phase or
	363	* dynamically by interpreter.
	364	*/
	365	return 0;
07dfc1d0 MD	366	default:
	367	printk(KERN_WARNING "Unknown reloc op type %u\n", op->op);
	368	return -EINVAL;
	369	}
	370	return 0;
	371	}
	372
	373	static
	374	int bytecode_is_linked(struct lttng_filter_bytecode_node *filter_bytecode,
63629d86	375	struct list_head *bytecode_runtime_head)
07dfc1d0 MD	376	{
	377	struct lttng_bytecode_runtime *bc_runtime;
	378
63629d86	379	list_for_each_entry(bc_runtime, bytecode_runtime_head, node) {
07dfc1d0 MD	380	if (bc_runtime->bc == filter_bytecode)
	381	return 1;
	382	}
	383	return 0;
	384	}
	385
	386	/*
	387	* Take a bytecode with reloc table and link it to an event to create a
	388	* bytecode runtime.
	389	*/
	390	static
63629d86 FD	391	int _lttng_filter_link_bytecode(const struct lttng_event_desc *event_desc,
63629d86 FD	392	struct lttng_ctx *ctx,
07dfc1d0 MD	393	struct lttng_filter_bytecode_node *filter_bytecode,
	394	struct list_head *insert_loc)
	395	{
	396	int ret, offset, next_offset;
	397	struct bytecode_runtime *runtime = NULL;
	398	size_t runtime_alloc_len;
	399
	400	if (!filter_bytecode)
	401	return 0;
	402	/* Bytecode already linked */
63629d86	403	if (bytecode_is_linked(filter_bytecode, insert_loc))
07dfc1d0 MD	404	return 0;
	405
	406	dbg_printk("Linking...\n");
	407
	408	/* We don't need the reloc table in the runtime */
	409	runtime_alloc_len = sizeof(*runtime) + filter_bytecode->bc.reloc_offset;
	410	runtime = kzalloc(runtime_alloc_len, GFP_KERNEL);
	411	if (!runtime) {
	412	ret = -ENOMEM;
	413	goto alloc_error;
	414	}
	415	runtime->p.bc = filter_bytecode;
63629d86	416	runtime->p.ctx = ctx;
07dfc1d0 MD	417	runtime->len = filter_bytecode->bc.reloc_offset;
07dfc1d0 MD	418	/* copy original bytecode */
3834b99f	419	memcpy(runtime->code, filter_bytecode->bc.data, runtime->len);
07dfc1d0 MD	420	/*
	421	* apply relocs. Those are a uint16_t (offset in bytecode)
	422	* followed by a string (field name).
	423	*/
	424	for (offset = filter_bytecode->bc.reloc_offset;
	425	offset < filter_bytecode->bc.len;
	426	offset = next_offset) {
	427	uint16_t reloc_offset =
	428	(uint16_t ) &filter_bytecode->bc.data[offset];
	429	const char *name =
	430	(const char *) &filter_bytecode->bc.data[offset + sizeof(uint16_t)];
	431
63629d86	432	ret = apply_reloc(event_desc, runtime, runtime->len, reloc_offset, name);
07dfc1d0 MD	433	if (ret) {
	434	goto link_error;
	435	}
	436	next_offset = offset + sizeof(uint16_t) + strlen(name) + 1;
	437	}
	438	/* Validate bytecode */
	439	ret = lttng_filter_validate_bytecode(runtime);
	440	if (ret) {
	441	goto link_error;
	442	}
	443	/* Specialize bytecode */
63629d86	444	ret = lttng_filter_specialize_bytecode(event_desc, runtime);
07dfc1d0 MD	445	if (ret) {
	446	goto link_error;
	447	}
	448	runtime->p.filter = lttng_filter_interpret_bytecode;
	449	runtime->p.link_failed = 0;
	450	list_add_rcu(&runtime->p.node, insert_loc);
	451	dbg_printk("Linking successful.\n");
	452	return 0;
	453
	454	link_error:
	455	runtime->p.filter = lttng_filter_false;
	456	runtime->p.link_failed = 1;
	457	list_add_rcu(&runtime->p.node, insert_loc);
	458	alloc_error:
	459	dbg_printk("Linking failed.\n");
	460	return ret;
	461	}
	462
	463	void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime)
	464	{
	465	struct lttng_filter_bytecode_node *bc = runtime->bc;
	466
	467	if (!bc->enabler->enabled \|\| runtime->link_failed)
	468	runtime->filter = lttng_filter_false;
	469	else
	470	runtime->filter = lttng_filter_interpret_bytecode;
	471	}
	472
	473	/*
	474	* Link bytecode for all enablers referenced by an event.
	475	*/
63629d86 FD	476	void lttng_enabler_link_bytecode(const struct lttng_event_desc *event_desc,
	477	struct lttng_ctx *ctx,
	478	struct list_head *bytecode_runtime_head,
07dfc1d0 MD	479	struct lttng_enabler *enabler)
	480	{
	481	struct lttng_filter_bytecode_node *bc;
	482	struct lttng_bytecode_runtime *runtime;
	483
	484	/* Can only be called for events with desc attached */
63629d86	485	WARN_ON_ONCE(!event_desc);
07dfc1d0 MD	486
	487	/* Link each bytecode. */
	488	list_for_each_entry(bc, &enabler->filter_bytecode_head, node) {
	489	int found = 0, ret;
	490	struct list_head *insert_loc;
	491
	492	list_for_each_entry(runtime,
63629d86	493	bytecode_runtime_head, node) {
07dfc1d0 MD	494	if (runtime->bc == bc) {
	495	found = 1;
	496	break;
	497	}
	498	}
	499	/* Skip bytecode already linked */
	500	if (found)
	501	continue;
	502
	503	/*
	504	* Insert at specified priority (seqnum) in increasing
	505	* order.
	506	*/
	507	list_for_each_entry_reverse(runtime,
63629d86	508	bytecode_runtime_head, node) {
07dfc1d0 MD	509	if (runtime->bc->bc.seqnum < bc->bc.seqnum) {
	510	/* insert here */
	511	insert_loc = &runtime->node;
	512	goto add_within;
	513	}
	514	}
	515	/* Add to head to list */
63629d86	516	insert_loc = bytecode_runtime_head;
07dfc1d0 MD	517	add_within:
07dfc1d0 MD	518	dbg_printk("linking bytecode\n");
63629d86 FD	519	ret = _lttng_filter_link_bytecode(event_desc, ctx, bc,
63629d86 FD	520	insert_loc);
07dfc1d0 MD	521	if (ret) {
	522	dbg_printk("[lttng filter] warning: cannot link event bytecode\n");
	523	}
	524	}
	525	}
	526
	527	/*
	528	* We own the filter_bytecode if we return success.
	529	*/
	530	int lttng_filter_enabler_attach_bytecode(struct lttng_enabler *enabler,
	531	struct lttng_filter_bytecode_node *filter_bytecode)
	532	{
	533	list_add(&filter_bytecode->node, &enabler->filter_bytecode_head);
	534	return 0;
	535	}
	536
	537	void lttng_free_enabler_filter_bytecode(struct lttng_enabler *enabler)
	538	{
	539	struct lttng_filter_bytecode_node filter_bytecode, tmp;
	540
	541	list_for_each_entry_safe(filter_bytecode, tmp,
	542	&enabler->filter_bytecode_head, node) {
	543	kfree(filter_bytecode);
	544	}
	545	}
	546
	547	void lttng_free_event_filter_runtime(struct lttng_event *event)
	548	{
	549	struct bytecode_runtime runtime, tmp;
	550
	551	list_for_each_entry_safe(runtime, tmp,
	552	&event->bytecode_runtime_head, p.node) {
3834b99f	553	kfree(runtime->data);
07dfc1d0 MD	554	kfree(runtime);
	555	}
	556	}