[lttng-modules.git] / src / lttng-bytecode.c

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

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

#include <lttng/lttng-bytecode.h>

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

	[ BYTECODE_OP_RETURN ] = "RETURN",

	/* binary */
	[ BYTECODE_OP_MUL ] = "MUL",
	[ BYTECODE_OP_DIV ] = "DIV",
	[ BYTECODE_OP_MOD ] = "MOD",
	[ BYTECODE_OP_PLUS ] = "PLUS",
	[ BYTECODE_OP_MINUS ] = "MINUS",
	[ BYTECODE_OP_BIT_RSHIFT ] = "BIT_RSHIFT",
	[ BYTECODE_OP_BIT_LSHIFT ] = "BIT_LSHIFT",
	[ BYTECODE_OP_BIT_AND ] = "BIT_AND",
	[ BYTECODE_OP_BIT_OR ] = "BIT_OR",
	[ BYTECODE_OP_BIT_XOR ] = "BIT_XOR",

	/* binary comparators */
	[ BYTECODE_OP_EQ ] = "EQ",
	[ BYTECODE_OP_NE ] = "NE",
	[ BYTECODE_OP_GT ] = "GT",
	[ BYTECODE_OP_LT ] = "LT",
	[ BYTECODE_OP_GE ] = "GE",
	[ BYTECODE_OP_LE ] = "LE",

	/* string binary comparators */
	[ BYTECODE_OP_EQ_STRING ] = "EQ_STRING",
	[ BYTECODE_OP_NE_STRING ] = "NE_STRING",
	[ BYTECODE_OP_GT_STRING ] = "GT_STRING",
	[ BYTECODE_OP_LT_STRING ] = "LT_STRING",
	[ BYTECODE_OP_GE_STRING ] = "GE_STRING",
	[ BYTECODE_OP_LE_STRING ] = "LE_STRING",

	/* s64 binary comparators */
	[ BYTECODE_OP_EQ_S64 ] = "EQ_S64",
	[ BYTECODE_OP_NE_S64 ] = "NE_S64",
	[ BYTECODE_OP_GT_S64 ] = "GT_S64",
	[ BYTECODE_OP_LT_S64 ] = "LT_S64",
	[ BYTECODE_OP_GE_S64 ] = "GE_S64",
	[ BYTECODE_OP_LE_S64 ] = "LE_S64",

	/* double binary comparators */
	[ BYTECODE_OP_EQ_DOUBLE ] = "EQ_DOUBLE",
	[ BYTECODE_OP_NE_DOUBLE ] = "NE_DOUBLE",
	[ BYTECODE_OP_GT_DOUBLE ] = "GT_DOUBLE",
	[ BYTECODE_OP_LT_DOUBLE ] = "LT_DOUBLE",
	[ BYTECODE_OP_GE_DOUBLE ] = "GE_DOUBLE",
	[ BYTECODE_OP_LE_DOUBLE ] = "LE_DOUBLE",

	/* Mixed S64-double binary comparators */
	[ BYTECODE_OP_EQ_DOUBLE_S64 ] = "EQ_DOUBLE_S64",
	[ BYTECODE_OP_NE_DOUBLE_S64 ] = "NE_DOUBLE_S64",
	[ BYTECODE_OP_GT_DOUBLE_S64 ] = "GT_DOUBLE_S64",
	[ BYTECODE_OP_LT_DOUBLE_S64 ] = "LT_DOUBLE_S64",
	[ BYTECODE_OP_GE_DOUBLE_S64 ] = "GE_DOUBLE_S64",
	[ BYTECODE_OP_LE_DOUBLE_S64 ] = "LE_DOUBLE_S64",

	[ BYTECODE_OP_EQ_S64_DOUBLE ] = "EQ_S64_DOUBLE",
	[ BYTECODE_OP_NE_S64_DOUBLE ] = "NE_S64_DOUBLE",
	[ BYTECODE_OP_GT_S64_DOUBLE ] = "GT_S64_DOUBLE",
	[ BYTECODE_OP_LT_S64_DOUBLE ] = "LT_S64_DOUBLE",
	[ BYTECODE_OP_GE_S64_DOUBLE ] = "GE_S64_DOUBLE",
	[ BYTECODE_OP_LE_S64_DOUBLE ] = "LE_S64_DOUBLE",

	/* unary */
	[ BYTECODE_OP_UNARY_PLUS ] = "UNARY_PLUS",
	[ BYTECODE_OP_UNARY_MINUS ] = "UNARY_MINUS",
	[ BYTECODE_OP_UNARY_NOT ] = "UNARY_NOT",
	[ BYTECODE_OP_UNARY_PLUS_S64 ] = "UNARY_PLUS_S64",
	[ BYTECODE_OP_UNARY_MINUS_S64 ] = "UNARY_MINUS_S64",
	[ BYTECODE_OP_UNARY_NOT_S64 ] = "UNARY_NOT_S64",
	[ BYTECODE_OP_UNARY_PLUS_DOUBLE ] = "UNARY_PLUS_DOUBLE",
	[ BYTECODE_OP_UNARY_MINUS_DOUBLE ] = "UNARY_MINUS_DOUBLE",
	[ BYTECODE_OP_UNARY_NOT_DOUBLE ] = "UNARY_NOT_DOUBLE",

	/* logical */
	[ BYTECODE_OP_AND ] = "AND",
	[ BYTECODE_OP_OR ] = "OR",

	/* load field ref */
	[ BYTECODE_OP_LOAD_FIELD_REF ] = "LOAD_FIELD_REF",
	[ BYTECODE_OP_LOAD_FIELD_REF_STRING ] = "LOAD_FIELD_REF_STRING",
	[ BYTECODE_OP_LOAD_FIELD_REF_SEQUENCE ] = "LOAD_FIELD_REF_SEQUENCE",
	[ BYTECODE_OP_LOAD_FIELD_REF_S64 ] = "LOAD_FIELD_REF_S64",
	[ BYTECODE_OP_LOAD_FIELD_REF_DOUBLE ] = "LOAD_FIELD_REF_DOUBLE",

	/* load from immediate operand */
	[ BYTECODE_OP_LOAD_STRING ] = "LOAD_STRING",
	[ BYTECODE_OP_LOAD_S64 ] = "LOAD_S64",
	[ BYTECODE_OP_LOAD_DOUBLE ] = "LOAD_DOUBLE",

	/* cast */
	[ BYTECODE_OP_CAST_TO_S64 ] = "CAST_TO_S64",
	[ BYTECODE_OP_CAST_DOUBLE_TO_S64 ] = "CAST_DOUBLE_TO_S64",
	[ BYTECODE_OP_CAST_NOP ] = "CAST_NOP",

	/* get context ref */
	[ BYTECODE_OP_GET_CONTEXT_REF ] = "GET_CONTEXT_REF",
	[ BYTECODE_OP_GET_CONTEXT_REF_STRING ] = "GET_CONTEXT_REF_STRING",
	[ BYTECODE_OP_GET_CONTEXT_REF_S64 ] = "GET_CONTEXT_REF_S64",
	[ BYTECODE_OP_GET_CONTEXT_REF_DOUBLE ] = "GET_CONTEXT_REF_DOUBLE",

	/* load userspace field ref */
	[ BYTECODE_OP_LOAD_FIELD_REF_USER_STRING ] = "LOAD_FIELD_REF_USER_STRING",
	[ BYTECODE_OP_LOAD_FIELD_REF_USER_SEQUENCE ] = "LOAD_FIELD_REF_USER_SEQUENCE",

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

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

	/*
	 * Instructions for recursive traversal through composed types.
	 */
	[ BYTECODE_OP_GET_CONTEXT_ROOT ] = "GET_CONTEXT_ROOT",
	[ BYTECODE_OP_GET_APP_CONTEXT_ROOT ] = "GET_APP_CONTEXT_ROOT",
	[ BYTECODE_OP_GET_PAYLOAD_ROOT ] = "GET_PAYLOAD_ROOT",

	[ BYTECODE_OP_GET_SYMBOL ] = "GET_SYMBOL",
	[ BYTECODE_OP_GET_SYMBOL_FIELD ] = "GET_SYMBOL_FIELD",
	[ BYTECODE_OP_GET_INDEX_U16 ] = "GET_INDEX_U16",
	[ BYTECODE_OP_GET_INDEX_U64 ] = "GET_INDEX_U64",

	[ BYTECODE_OP_LOAD_FIELD ] = "LOAD_FIELD",
	[ BYTECODE_OP_LOAD_FIELD_S8 ] = "LOAD_FIELD_S8",
	[ BYTECODE_OP_LOAD_FIELD_S16 ] = "LOAD_FIELD_S16",
	[ BYTECODE_OP_LOAD_FIELD_S32 ] = "LOAD_FIELD_S32",
	[ BYTECODE_OP_LOAD_FIELD_S64 ] = "LOAD_FIELD_S64",
	[ BYTECODE_OP_LOAD_FIELD_U8 ] = "LOAD_FIELD_U8",
	[ BYTECODE_OP_LOAD_FIELD_U16 ] = "LOAD_FIELD_U16",
	[ BYTECODE_OP_LOAD_FIELD_U32 ] = "LOAD_FIELD_U32",
	[ BYTECODE_OP_LOAD_FIELD_U64 ] = "LOAD_FIELD_U64",
	[ BYTECODE_OP_LOAD_FIELD_STRING ] = "LOAD_FIELD_STRING",
	[ BYTECODE_OP_LOAD_FIELD_SEQUENCE ] = "LOAD_FIELD_SEQUENCE",
	[ BYTECODE_OP_LOAD_FIELD_DOUBLE ] = "LOAD_FIELD_DOUBLE",

	[ BYTECODE_OP_UNARY_BIT_NOT ] = "UNARY_BIT_NOT",

	[ BYTECODE_OP_RETURN_S64 ] = "RETURN_S64",
};

const char *lttng_bytecode_print_op(enum bytecode_op op)
{
	if (op >= NR_BYTECODE_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 bytecode_op bytecode_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 (fields[i].nofilter)
			continue;
		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_nestable:
			field_offset += sizeof(int64_t);
			break;
		case atype_array_nestable:
			if (!lttng_is_bytewise_integer(fields[i].type.u.array_nestable.elem_type))
				return -EINVAL;
			field_offset += sizeof(unsigned long);
			field_offset += sizeof(void *);
			break;
		case atype_sequence_nestable:
			if (!lttng_is_bytewise_integer(fields[i].type.u.sequence_nestable.elem_type))
				return -EINVAL;
			field_offset += sizeof(unsigned long);
			field_offset += sizeof(void *);
			break;
		case atype_string:
			field_offset += sizeof(void *);
			break;
		case atype_struct_nestable:	/* Unsupported. */
		case atype_variant_nestable:	/* 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 (bytecode_op) {
	case BYTECODE_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_nestable:
			op->op = BYTECODE_OP_LOAD_FIELD_REF_S64;
			break;
		case atype_array_nestable:
		case atype_sequence_nestable:
			if (field->user)
				op->op = BYTECODE_OP_LOAD_FIELD_REF_USER_SEQUENCE;
			else
				op->op = BYTECODE_OP_LOAD_FIELD_REF_SEQUENCE;
			break;
		case atype_string:
			if (field->user)
				op->op = BYTECODE_OP_LOAD_FIELD_REF_USER_STRING;
			else
				op->op = BYTECODE_OP_LOAD_FIELD_REF_STRING;
			break;
		case atype_struct_nestable:	/* Unsupported. */
		case atype_variant_nestable:	/* 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 bytecode_op bytecode_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 (bytecode_op) {
	case BYTECODE_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_nestable:
			op->op = BYTECODE_OP_GET_CONTEXT_REF_S64;
			break;
			/* Sequence and array supported as string */
		case atype_string:
			BUG_ON(ctx_field->event_field.user);
			op->op = BYTECODE_OP_GET_CONTEXT_REF_STRING;
			break;
		case atype_array_nestable:
			if (!lttng_is_bytewise_integer(ctx_field->event_field.type.u.array_nestable.elem_type))
				return -EINVAL;
			BUG_ON(ctx_field->event_field.user);
			op->op = BYTECODE_OP_GET_CONTEXT_REF_STRING;
			break;
		case atype_sequence_nestable:
			if (!lttng_is_bytewise_integer(ctx_field->event_field.type.u.sequence_nestable.elem_type))
				return -EINVAL;
			BUG_ON(ctx_field->event_field.user);
			op->op = BYTECODE_OP_GET_CONTEXT_REF_STRING;
			break;
		case atype_struct_nestable:	/* Unsupported. */
		case atype_variant_nestable:	/* 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 BYTECODE_OP_LOAD_FIELD_REF:
		return apply_field_reloc(event_desc, runtime, runtime_len,
			reloc_offset, name, op->op);
	case BYTECODE_OP_GET_CONTEXT_REF:
		return apply_context_reloc(runtime, runtime_len,
			reloc_offset, name, op->op);
	case BYTECODE_OP_GET_SYMBOL:
	case BYTECODE_OP_GET_SYMBOL_FIELD:
		/*
		 * Will be handled by load specialize phase or
		 * dynamically by interpreter.
		 */
		return 0;
	default:
		printk(KERN_WARNING "LTTng: filter: Unknown reloc op type %u\n", op->op);
		return -EINVAL;
	}
	return 0;
}

static
int bytecode_is_linked(struct lttng_bytecode_node *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 == bytecode)
			return 1;
	}
	return 0;
}

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

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

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

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

	switch (bytecode->type) {
	case LTTNG_BYTECODE_NODE_TYPE_FILTER:
		runtime->p.interpreter_funcs.filter = lttng_bytecode_filter_interpret;
		break;
	default:
		WARN_ON(1);
	}

	runtime->p.link_failed = 0;
	list_add_rcu(&runtime->p.node, insert_loc);
	dbg_printk("Linking successful.\n");
	return 0;

link_error:

	switch (bytecode->type) {
	case LTTNG_BYTECODE_NODE_TYPE_FILTER:
		runtime->p.interpreter_funcs.filter = lttng_bytecode_filter_interpret_false;
		break;
	default:
		WARN_ON(1);
	}
	runtime->p.link_failed = 1;
	list_add_rcu(&runtime->p.node, insert_loc);
alloc_error:
	dbg_printk("Linking failed.\n");
	return ret;
}

void lttng_bytecode_filter_sync_state(struct lttng_bytecode_runtime *runtime)
{
	struct lttng_bytecode_node *bc = runtime->bc;

	if (!bc->enabler->enabled || runtime->link_failed)
		runtime->interpreter_funcs.filter = lttng_bytecode_filter_interpret_false;
	else
		runtime->interpreter_funcs.filter = lttng_bytecode_filter_interpret;
}

/*
 * Given the lists of bytecode programs of an instance (trigger or event) and
 * of a matching enabler, try to link all the enabler's bytecode programs with
 * the instance.
 *
 * This function is called after we confirmed that name enabler and the
 * instance are matching names (or glob pattern matching).
 */
void lttng_enabler_link_bytecode(const struct lttng_event_desc *event_desc,
		struct lttng_ctx *ctx,
		struct list_head *instance_bytecode_head,
		struct list_head *enabler_bytecode_head)
{
	struct lttng_bytecode_node *enabler_bc;
	struct lttng_bytecode_runtime *runtime;

	WARN_ON_ONCE(!event_desc);

	/* Go over all the bytecode programs of the enabler.  */
	list_for_each_entry(enabler_bc, enabler_bytecode_head, node) {
		int found = 0, ret;
		struct list_head *insert_loc;

		/*
		 * Check if the current enabler bytecode program is already
		 * linked with the instance.
		 */
		list_for_each_entry(runtime, instance_bytecode_head, node) {
			if (runtime->bc == enabler_bc) {
				found = 1;
				break;
			}
		}

		/*
		 * Skip bytecode already linked, go to the next enabler
		 * bytecode program.
		 */
		if (found)
			continue;

		/*
		 * Insert at specified priority (seqnum) in increasing
		 * order. If there already is a bytecode of the same priority,
		 * insert the new bytecode right after it.
		 */
		list_for_each_entry_reverse(runtime,
				instance_bytecode_head, node) {
			if (runtime->bc->bc.seqnum <= enabler_bc->bc.seqnum) {
				/* insert here */
				insert_loc = &runtime->node;
				goto add_within;
			}
		}
		/* Add to head to list */
		insert_loc = instance_bytecode_head;
	add_within:
		dbg_printk("linking bytecode\n");
		ret = link_bytecode(event_desc, ctx, enabler_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_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_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->filter_bytecode_runtime_head, p.node) {
		kfree(runtime->data);
		kfree(runtime);
	}
}
Commit	Line	Data
9f36eaed MJ	1	/* SPDX-License-Identifier: MIT
9f36eaed MJ	2	*
80c2a69a	3	* lttng-bytecode.c
07dfc1d0	4	*
80c2a69a	5	* LTTng modules bytecode code.
07dfc1d0	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
80c2a69a	13	#include <lttng/lttng-bytecode.h>
07dfc1d0 MD	14
07dfc1d0 MD	15	static const char *opnames[] = {
80c2a69a	16	[ BYTECODE_OP_UNKNOWN ] = "UNKNOWN",
07dfc1d0	17
80c2a69a	18	[ BYTECODE_OP_RETURN ] = "RETURN",
07dfc1d0 MD	19
07dfc1d0 MD	20	/* binary */
80c2a69a FD	21	[ BYTECODE_OP_MUL ] = "MUL",
	22	[ BYTECODE_OP_DIV ] = "DIV",
	23	[ BYTECODE_OP_MOD ] = "MOD",
	24	[ BYTECODE_OP_PLUS ] = "PLUS",
	25	[ BYTECODE_OP_MINUS ] = "MINUS",
	26	[ BYTECODE_OP_BIT_RSHIFT ] = "BIT_RSHIFT",
	27	[ BYTECODE_OP_BIT_LSHIFT ] = "BIT_LSHIFT",
	28	[ BYTECODE_OP_BIT_AND ] = "BIT_AND",
	29	[ BYTECODE_OP_BIT_OR ] = "BIT_OR",
	30	[ BYTECODE_OP_BIT_XOR ] = "BIT_XOR",
07dfc1d0 MD	31
07dfc1d0 MD	32	/* binary comparators */
80c2a69a FD	33	[ BYTECODE_OP_EQ ] = "EQ",
	34	[ BYTECODE_OP_NE ] = "NE",
	35	[ BYTECODE_OP_GT ] = "GT",
	36	[ BYTECODE_OP_LT ] = "LT",
	37	[ BYTECODE_OP_GE ] = "GE",
	38	[ BYTECODE_OP_LE ] = "LE",
07dfc1d0 MD	39
07dfc1d0 MD	40	/* string binary comparators */
80c2a69a FD	41	[ BYTECODE_OP_EQ_STRING ] = "EQ_STRING",
	42	[ BYTECODE_OP_NE_STRING ] = "NE_STRING",
	43	[ BYTECODE_OP_GT_STRING ] = "GT_STRING",
	44	[ BYTECODE_OP_LT_STRING ] = "LT_STRING",
	45	[ BYTECODE_OP_GE_STRING ] = "GE_STRING",
	46	[ BYTECODE_OP_LE_STRING ] = "LE_STRING",
07dfc1d0 MD	47
07dfc1d0 MD	48	/* s64 binary comparators */
80c2a69a FD	49	[ BYTECODE_OP_EQ_S64 ] = "EQ_S64",
	50	[ BYTECODE_OP_NE_S64 ] = "NE_S64",
	51	[ BYTECODE_OP_GT_S64 ] = "GT_S64",
	52	[ BYTECODE_OP_LT_S64 ] = "LT_S64",
	53	[ BYTECODE_OP_GE_S64 ] = "GE_S64",
	54	[ BYTECODE_OP_LE_S64 ] = "LE_S64",
07dfc1d0 MD	55
07dfc1d0 MD	56	/* double binary comparators */
80c2a69a FD	57	[ BYTECODE_OP_EQ_DOUBLE ] = "EQ_DOUBLE",
	58	[ BYTECODE_OP_NE_DOUBLE ] = "NE_DOUBLE",
	59	[ BYTECODE_OP_GT_DOUBLE ] = "GT_DOUBLE",
	60	[ BYTECODE_OP_LT_DOUBLE ] = "LT_DOUBLE",
	61	[ BYTECODE_OP_GE_DOUBLE ] = "GE_DOUBLE",
	62	[ BYTECODE_OP_LE_DOUBLE ] = "LE_DOUBLE",
07dfc1d0 MD	63
07dfc1d0 MD	64	/* Mixed S64-double binary comparators */
80c2a69a FD	65	[ BYTECODE_OP_EQ_DOUBLE_S64 ] = "EQ_DOUBLE_S64",
	66	[ BYTECODE_OP_NE_DOUBLE_S64 ] = "NE_DOUBLE_S64",
	67	[ BYTECODE_OP_GT_DOUBLE_S64 ] = "GT_DOUBLE_S64",
	68	[ BYTECODE_OP_LT_DOUBLE_S64 ] = "LT_DOUBLE_S64",
	69	[ BYTECODE_OP_GE_DOUBLE_S64 ] = "GE_DOUBLE_S64",
	70	[ BYTECODE_OP_LE_DOUBLE_S64 ] = "LE_DOUBLE_S64",
	71
	72	[ BYTECODE_OP_EQ_S64_DOUBLE ] = "EQ_S64_DOUBLE",
	73	[ BYTECODE_OP_NE_S64_DOUBLE ] = "NE_S64_DOUBLE",
	74	[ BYTECODE_OP_GT_S64_DOUBLE ] = "GT_S64_DOUBLE",
	75	[ BYTECODE_OP_LT_S64_DOUBLE ] = "LT_S64_DOUBLE",
	76	[ BYTECODE_OP_GE_S64_DOUBLE ] = "GE_S64_DOUBLE",
	77	[ BYTECODE_OP_LE_S64_DOUBLE ] = "LE_S64_DOUBLE",
07dfc1d0 MD	78
07dfc1d0 MD	79	/* unary */
80c2a69a FD	80	[ BYTECODE_OP_UNARY_PLUS ] = "UNARY_PLUS",
	81	[ BYTECODE_OP_UNARY_MINUS ] = "UNARY_MINUS",
	82	[ BYTECODE_OP_UNARY_NOT ] = "UNARY_NOT",
	83	[ BYTECODE_OP_UNARY_PLUS_S64 ] = "UNARY_PLUS_S64",
	84	[ BYTECODE_OP_UNARY_MINUS_S64 ] = "UNARY_MINUS_S64",
	85	[ BYTECODE_OP_UNARY_NOT_S64 ] = "UNARY_NOT_S64",
	86	[ BYTECODE_OP_UNARY_PLUS_DOUBLE ] = "UNARY_PLUS_DOUBLE",
	87	[ BYTECODE_OP_UNARY_MINUS_DOUBLE ] = "UNARY_MINUS_DOUBLE",
	88	[ BYTECODE_OP_UNARY_NOT_DOUBLE ] = "UNARY_NOT_DOUBLE",
07dfc1d0 MD	89
07dfc1d0 MD	90	/* logical */
80c2a69a FD	91	[ BYTECODE_OP_AND ] = "AND",
80c2a69a FD	92	[ BYTECODE_OP_OR ] = "OR",
07dfc1d0 MD	93
07dfc1d0 MD	94	/* load field ref */
80c2a69a FD	95	[ BYTECODE_OP_LOAD_FIELD_REF ] = "LOAD_FIELD_REF",
	96	[ BYTECODE_OP_LOAD_FIELD_REF_STRING ] = "LOAD_FIELD_REF_STRING",
	97	[ BYTECODE_OP_LOAD_FIELD_REF_SEQUENCE ] = "LOAD_FIELD_REF_SEQUENCE",
	98	[ BYTECODE_OP_LOAD_FIELD_REF_S64 ] = "LOAD_FIELD_REF_S64",
	99	[ BYTECODE_OP_LOAD_FIELD_REF_DOUBLE ] = "LOAD_FIELD_REF_DOUBLE",
07dfc1d0 MD	100
07dfc1d0 MD	101	/* load from immediate operand */
80c2a69a FD	102	[ BYTECODE_OP_LOAD_STRING ] = "LOAD_STRING",
	103	[ BYTECODE_OP_LOAD_S64 ] = "LOAD_S64",
	104	[ BYTECODE_OP_LOAD_DOUBLE ] = "LOAD_DOUBLE",
07dfc1d0 MD	105
07dfc1d0 MD	106	/* cast */
80c2a69a FD	107	[ BYTECODE_OP_CAST_TO_S64 ] = "CAST_TO_S64",
	108	[ BYTECODE_OP_CAST_DOUBLE_TO_S64 ] = "CAST_DOUBLE_TO_S64",
	109	[ BYTECODE_OP_CAST_NOP ] = "CAST_NOP",
07dfc1d0 MD	110
07dfc1d0 MD	111	/* get context ref */
80c2a69a FD	112	[ BYTECODE_OP_GET_CONTEXT_REF ] = "GET_CONTEXT_REF",
	113	[ BYTECODE_OP_GET_CONTEXT_REF_STRING ] = "GET_CONTEXT_REF_STRING",
	114	[ BYTECODE_OP_GET_CONTEXT_REF_S64 ] = "GET_CONTEXT_REF_S64",
	115	[ BYTECODE_OP_GET_CONTEXT_REF_DOUBLE ] = "GET_CONTEXT_REF_DOUBLE",
f127e61e MD	116
f127e61e MD	117	/* load userspace field ref */
80c2a69a FD	118	[ BYTECODE_OP_LOAD_FIELD_REF_USER_STRING ] = "LOAD_FIELD_REF_USER_STRING",
80c2a69a FD	119	[ BYTECODE_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	*/
80c2a69a	125	[ BYTECODE_OP_LOAD_STAR_GLOB_STRING ] = "LOAD_STAR_GLOB_STRING",
83fb57ab MD	126
83fb57ab MD	127	/* globbing pattern binary operator: apply to */
80c2a69a FD	128	[ BYTECODE_OP_EQ_STAR_GLOB_STRING ] = "EQ_STAR_GLOB_STRING",
80c2a69a FD	129	[ BYTECODE_OP_NE_STAR_GLOB_STRING ] = "NE_STAR_GLOB_STRING",
3834b99f MD	130
	131	/*
	132	* Instructions for recursive traversal through composed types.
	133	*/
80c2a69a FD	134	[ BYTECODE_OP_GET_CONTEXT_ROOT ] = "GET_CONTEXT_ROOT",
	135	[ BYTECODE_OP_GET_APP_CONTEXT_ROOT ] = "GET_APP_CONTEXT_ROOT",
	136	[ BYTECODE_OP_GET_PAYLOAD_ROOT ] = "GET_PAYLOAD_ROOT",
	137
	138	[ BYTECODE_OP_GET_SYMBOL ] = "GET_SYMBOL",
	139	[ BYTECODE_OP_GET_SYMBOL_FIELD ] = "GET_SYMBOL_FIELD",
	140	[ BYTECODE_OP_GET_INDEX_U16 ] = "GET_INDEX_U16",
	141	[ BYTECODE_OP_GET_INDEX_U64 ] = "GET_INDEX_U64",
	142
	143	[ BYTECODE_OP_LOAD_FIELD ] = "LOAD_FIELD",
	144	[ BYTECODE_OP_LOAD_FIELD_S8 ] = "LOAD_FIELD_S8",
	145	[ BYTECODE_OP_LOAD_FIELD_S16 ] = "LOAD_FIELD_S16",
	146	[ BYTECODE_OP_LOAD_FIELD_S32 ] = "LOAD_FIELD_S32",
	147	[ BYTECODE_OP_LOAD_FIELD_S64 ] = "LOAD_FIELD_S64",
	148	[ BYTECODE_OP_LOAD_FIELD_U8 ] = "LOAD_FIELD_U8",
	149	[ BYTECODE_OP_LOAD_FIELD_U16 ] = "LOAD_FIELD_U16",
	150	[ BYTECODE_OP_LOAD_FIELD_U32 ] = "LOAD_FIELD_U32",
	151	[ BYTECODE_OP_LOAD_FIELD_U64 ] = "LOAD_FIELD_U64",
	152	[ BYTECODE_OP_LOAD_FIELD_STRING ] = "LOAD_FIELD_STRING",
	153	[ BYTECODE_OP_LOAD_FIELD_SEQUENCE ] = "LOAD_FIELD_SEQUENCE",
	154	[ BYTECODE_OP_LOAD_FIELD_DOUBLE ] = "LOAD_FIELD_DOUBLE",
	155
	156	[ BYTECODE_OP_UNARY_BIT_NOT ] = "UNARY_BIT_NOT",
	157
	158	[ BYTECODE_OP_RETURN_S64 ] = "RETURN_S64",
07dfc1d0 MD	159	};
07dfc1d0 MD	160
80c2a69a	161	const char *lttng_bytecode_print_op(enum bytecode_op op)
07dfc1d0	162	{
80c2a69a	163	if (op >= NR_BYTECODE_OPS)
07dfc1d0 MD	164	return "UNKNOWN";
	165	else
	166	return opnames[op];
	167	}
	168
	169	static
2dfda770	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	174	const char *field_name,
80c2a69a	175	enum bytecode_op bytecode_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 */
2dfda770	185	if (!event_desc)
07dfc1d0	186	return -EINVAL;
2dfda770	187	fields = event_desc->fields;
07dfc1d0 MD	188	if (!fields)
07dfc1d0 MD	189	return -EINVAL;
2dfda770	190	nr_fields = event_desc->nr_fields;
07dfc1d0	191	for (i = 0; i < nr_fields; i++) {
ceabb767 MD	192	if (fields[i].nofilter)
ceabb767 MD	193	continue;
07dfc1d0 MD	194	if (!strcmp(fields[i].name, field_name)) {
	195	field = &fields[i];
	196	break;
	197	}
	198	/* compute field offset */
	199	switch (fields[i].type.atype) {
	200	case atype_integer:
ceabb767	201	case atype_enum_nestable:
07dfc1d0 MD	202	field_offset += sizeof(int64_t);
07dfc1d0 MD	203	break;
ceabb767 MD	204	case atype_array_nestable:
	205	if (!lttng_is_bytewise_integer(fields[i].type.u.array_nestable.elem_type))
	206	return -EINVAL;
	207	field_offset += sizeof(unsigned long);
	208	field_offset += sizeof(void *);
	209	break;
	210	case atype_sequence_nestable:
	211	if (!lttng_is_bytewise_integer(fields[i].type.u.sequence_nestable.elem_type))
	212	return -EINVAL;
07dfc1d0 MD	213	field_offset += sizeof(unsigned long);
	214	field_offset += sizeof(void *);
	215	break;
	216	case atype_string:
	217	field_offset += sizeof(void *);
	218	break;
ceabb767 MD	219	case atype_struct_nestable: /* Unsupported. */
ceabb767 MD	220	case atype_variant_nestable: /* Unsupported. */
07dfc1d0 MD	221	default:
	222	return -EINVAL;
	223	}
	224	}
	225	if (!field)
	226	return -EINVAL;
	227
	228	/* Check if field offset is too large for 16-bit offset */
f127e61e	229	if (field_offset > LTTNG_KERNEL_FILTER_BYTECODE_MAX_LEN - 1)
07dfc1d0 MD	230	return -EINVAL;
	231
	232	/* set type */
3834b99f MD	233	op = (struct load_op *) &runtime->code[reloc_offset];
3834b99f MD	234
80c2a69a FD	235	switch (bytecode_op) {
80c2a69a FD	236	case BYTECODE_OP_LOAD_FIELD_REF:
3834b99f MD	237	{
	238	struct field_ref *field_ref;
	239
	240	field_ref = (struct field_ref *) op->data;
	241	switch (field->type.atype) {
	242	case atype_integer:
ceabb767	243	case atype_enum_nestable:
80c2a69a	244	op->op = BYTECODE_OP_LOAD_FIELD_REF_S64;
3834b99f	245	break;
ceabb767 MD	246	case atype_array_nestable:
ceabb767 MD	247	case atype_sequence_nestable:
3834b99f	248	if (field->user)
80c2a69a	249	op->op = BYTECODE_OP_LOAD_FIELD_REF_USER_SEQUENCE;
3834b99f	250	else
80c2a69a	251	op->op = BYTECODE_OP_LOAD_FIELD_REF_SEQUENCE;
3834b99f MD	252	break;
	253	case atype_string:
	254	if (field->user)
80c2a69a	255	op->op = BYTECODE_OP_LOAD_FIELD_REF_USER_STRING;
3834b99f	256	else
80c2a69a	257	op->op = BYTECODE_OP_LOAD_FIELD_REF_STRING;
3834b99f	258	break;
ceabb767 MD	259	case atype_struct_nestable: /* Unsupported. */
ceabb767 MD	260	case atype_variant_nestable: /* Unsupported. */
3834b99f MD	261	default:
	262	return -EINVAL;
	263	}
	264	/* set offset */
	265	field_ref->offset = (uint16_t) field_offset;
07dfc1d0	266	break;
3834b99f	267	}
07dfc1d0 MD	268	default:
	269	return -EINVAL;
	270	}
07dfc1d0 MD	271	return 0;
	272	}
	273
	274	static
2dfda770	275	int apply_context_reloc(struct bytecode_runtime *runtime,
07dfc1d0 MD	276	uint32_t runtime_len,
07dfc1d0 MD	277	uint32_t reloc_offset,
3834b99f	278	const char *context_name,
80c2a69a	279	enum bytecode_op bytecode_op)
07dfc1d0	280	{
07dfc1d0 MD	281	struct load_op *op;
	282	struct lttng_ctx_field *ctx_field;
	283	int idx;
	284
	285	dbg_printk("Apply context reloc: %u %s\n", reloc_offset, context_name);
	286
	287	/* Get context index */
	288	idx = lttng_get_context_index(lttng_static_ctx, context_name);
	289	if (idx < 0)
	290	return -ENOENT;
	291
	292	/* Check if idx is too large for 16-bit offset */
f127e61e	293	if (idx > LTTNG_KERNEL_FILTER_BYTECODE_MAX_LEN - 1)
07dfc1d0 MD	294	return -EINVAL;
	295
	296	/* Get context return type */
	297	ctx_field = &lttng_static_ctx->fields[idx];
3834b99f MD	298	op = (struct load_op *) &runtime->code[reloc_offset];
3834b99f MD	299
80c2a69a FD	300	switch (bytecode_op) {
80c2a69a FD	301	case BYTECODE_OP_GET_CONTEXT_REF:
3834b99f MD	302	{
	303	struct field_ref *field_ref;
	304
	305	field_ref = (struct field_ref *) op->data;
	306	switch (ctx_field->event_field.type.atype) {
	307	case atype_integer:
ceabb767	308	case atype_enum_nestable:
80c2a69a	309	op->op = BYTECODE_OP_GET_CONTEXT_REF_S64;
3834b99f MD	310	break;
	311	/* Sequence and array supported as string */
	312	case atype_string:
3834b99f	313	BUG_ON(ctx_field->event_field.user);
80c2a69a	314	op->op = BYTECODE_OP_GET_CONTEXT_REF_STRING;
3834b99f	315	break;
ceabb767 MD	316	case atype_array_nestable:
	317	if (!lttng_is_bytewise_integer(ctx_field->event_field.type.u.array_nestable.elem_type))
	318	return -EINVAL;
	319	BUG_ON(ctx_field->event_field.user);
80c2a69a	320	op->op = BYTECODE_OP_GET_CONTEXT_REF_STRING;
ceabb767 MD	321	break;
	322	case atype_sequence_nestable:
	323	if (!lttng_is_bytewise_integer(ctx_field->event_field.type.u.sequence_nestable.elem_type))
	324	return -EINVAL;
	325	BUG_ON(ctx_field->event_field.user);
80c2a69a	326	op->op = BYTECODE_OP_GET_CONTEXT_REF_STRING;
ceabb767 MD	327	break;
	328	case atype_struct_nestable: /* Unsupported. */
	329	case atype_variant_nestable: /* Unsupported. */
3834b99f MD	330	default:
	331	return -EINVAL;
	332	}
	333	/* set offset to context index within channel contexts */
	334	field_ref->offset = (uint16_t) idx;
07dfc1d0	335	break;
3834b99f	336	}
07dfc1d0 MD	337	default:
	338	return -EINVAL;
	339	}
07dfc1d0 MD	340	return 0;
	341	}
	342
	343	static
2dfda770	344	int apply_reloc(const struct lttng_event_desc *event_desc,
07dfc1d0 MD	345	struct bytecode_runtime *runtime,
	346	uint32_t runtime_len,
	347	uint32_t reloc_offset,
	348	const char *name)
	349	{
	350	struct load_op *op;
	351
	352	dbg_printk("Apply reloc: %u %s\n", reloc_offset, name);
	353
	354	/* Ensure that the reloc is within the code */
	355	if (runtime_len - reloc_offset < sizeof(uint16_t))
	356	return -EINVAL;
	357
3834b99f	358	op = (struct load_op *) &runtime->code[reloc_offset];
07dfc1d0	359	switch (op->op) {
80c2a69a	360	case BYTECODE_OP_LOAD_FIELD_REF:
2dfda770	361	return apply_field_reloc(event_desc, runtime, runtime_len,
3834b99f	362	reloc_offset, name, op->op);
80c2a69a	363	case BYTECODE_OP_GET_CONTEXT_REF:
2dfda770	364	return apply_context_reloc(runtime, runtime_len,
3834b99f	365	reloc_offset, name, op->op);
80c2a69a FD	366	case BYTECODE_OP_GET_SYMBOL:
80c2a69a FD	367	case BYTECODE_OP_GET_SYMBOL_FIELD:
3834b99f MD	368	/*
	369	* Will be handled by load specialize phase or
	370	* dynamically by interpreter.
	371	*/
	372	return 0;
07dfc1d0	373	default:
5a15f70c	374	printk(KERN_WARNING "LTTng: filter: Unknown reloc op type %u\n", op->op);
07dfc1d0 MD	375	return -EINVAL;
	376	}
	377	return 0;
	378	}
	379
	380	static
89ec2b91	381	int bytecode_is_linked(struct lttng_bytecode_node *bytecode,
2dfda770	382	struct list_head *bytecode_runtime_head)
07dfc1d0 MD	383	{
	384	struct lttng_bytecode_runtime *bc_runtime;
	385
2dfda770	386	list_for_each_entry(bc_runtime, bytecode_runtime_head, node) {
89ec2b91	387	if (bc_runtime->bc == bytecode)
07dfc1d0 MD	388	return 1;
	389	}
	390	return 0;
	391	}
	392
	393	/*
	394	* Take a bytecode with reloc table and link it to an event to create a
	395	* bytecode runtime.
	396	*/
	397	static
fdd179d7	398	int link_bytecode(const struct lttng_event_desc *event_desc,
2dfda770	399	struct lttng_ctx *ctx,
89ec2b91	400	struct lttng_bytecode_node *bytecode,
07dfc1d0 MD	401	struct list_head *insert_loc)
	402	{
	403	int ret, offset, next_offset;
	404	struct bytecode_runtime *runtime = NULL;
	405	size_t runtime_alloc_len;
	406
89ec2b91	407	if (!bytecode)
07dfc1d0 MD	408	return 0;
07dfc1d0 MD	409	/* Bytecode already linked */
89ec2b91	410	if (bytecode_is_linked(bytecode, insert_loc))
07dfc1d0 MD	411	return 0;
	412
	413	dbg_printk("Linking...\n");
	414
	415	/* We don't need the reloc table in the runtime */
89ec2b91	416	runtime_alloc_len = sizeof(*runtime) + bytecode->bc.reloc_offset;
07dfc1d0 MD	417	runtime = kzalloc(runtime_alloc_len, GFP_KERNEL);
	418	if (!runtime) {
	419	ret = -ENOMEM;
	420	goto alloc_error;
	421	}
89ec2b91	422	runtime->p.bc = bytecode;
2dfda770	423	runtime->p.ctx = ctx;
89ec2b91	424	runtime->len = bytecode->bc.reloc_offset;
07dfc1d0	425	/* copy original bytecode */
89ec2b91	426	memcpy(runtime->code, bytecode->bc.data, runtime->len);
07dfc1d0 MD	427	/*
	428	* apply relocs. Those are a uint16_t (offset in bytecode)
	429	* followed by a string (field name).
	430	*/
89ec2b91 FD	431	for (offset = bytecode->bc.reloc_offset;
89ec2b91 FD	432	offset < bytecode->bc.len;
07dfc1d0 MD	433	offset = next_offset) {
07dfc1d0 MD	434	uint16_t reloc_offset =
89ec2b91	435	(uint16_t ) &bytecode->bc.data[offset];
07dfc1d0	436	const char *name =
89ec2b91	437	(const char *) &bytecode->bc.data[offset + sizeof(uint16_t)];
07dfc1d0	438
2dfda770	439	ret = apply_reloc(event_desc, runtime, runtime->len, reloc_offset, name);
07dfc1d0 MD	440	if (ret) {
	441	goto link_error;
	442	}
	443	next_offset = offset + sizeof(uint16_t) + strlen(name) + 1;
	444	}
	445	/* Validate bytecode */
80c2a69a	446	ret = lttng_bytecode_validate(runtime);
07dfc1d0 MD	447	if (ret) {
	448	goto link_error;
	449	}
	450	/* Specialize bytecode */
80c2a69a	451	ret = lttng_bytecode_specialize(event_desc, runtime);
07dfc1d0 MD	452	if (ret) {
	453	goto link_error;
	454	}
3d650c7b FD	455
	456	switch (bytecode->type) {
	457	case LTTNG_BYTECODE_NODE_TYPE_FILTER:
	458	runtime->p.interpreter_funcs.filter = lttng_bytecode_filter_interpret;
	459	break;
	460	default:
	461	WARN_ON(1);
	462	}
	463
07dfc1d0 MD	464	runtime->p.link_failed = 0;
	465	list_add_rcu(&runtime->p.node, insert_loc);
	466	dbg_printk("Linking successful.\n");
	467	return 0;
	468
	469	link_error:
3d650c7b FD	470
	471	switch (bytecode->type) {
	472	case LTTNG_BYTECODE_NODE_TYPE_FILTER:
	473	runtime->p.interpreter_funcs.filter = lttng_bytecode_filter_interpret_false;
	474	break;
	475	default:
	476	WARN_ON(1);
	477	}
07dfc1d0 MD	478	runtime->p.link_failed = 1;
	479	list_add_rcu(&runtime->p.node, insert_loc);
	480	alloc_error:
	481	dbg_printk("Linking failed.\n");
	482	return ret;
	483	}
	484
0b365677	485	void lttng_bytecode_filter_sync_state(struct lttng_bytecode_runtime *runtime)
07dfc1d0	486	{
89ec2b91	487	struct lttng_bytecode_node *bc = runtime->bc;
07dfc1d0 MD	488
07dfc1d0 MD	489	if (!bc->enabler->enabled \|\| runtime->link_failed)
3d650c7b	490	runtime->interpreter_funcs.filter = lttng_bytecode_filter_interpret_false;
07dfc1d0	491	else
3d650c7b	492	runtime->interpreter_funcs.filter = lttng_bytecode_filter_interpret;
07dfc1d0 MD	493	}
	494
	495	/*
60206944 FD	496	* Given the lists of bytecode programs of an instance (trigger or event) and
	497	* of a matching enabler, try to link all the enabler's bytecode programs with
	498	* the instance.
	499	*
	500	* This function is called after we confirmed that name enabler and the
	501	* instance are matching names (or glob pattern matching).
07dfc1d0	502	*/
2dfda770 FD	503	void lttng_enabler_link_bytecode(const struct lttng_event_desc *event_desc,
2dfda770 FD	504	struct lttng_ctx *ctx,
60206944 FD	505	struct list_head *instance_bytecode_head,
60206944 FD	506	struct list_head *enabler_bytecode_head)
07dfc1d0	507	{
60206944	508	struct lttng_bytecode_node *enabler_bc;
07dfc1d0 MD	509	struct lttng_bytecode_runtime *runtime;
07dfc1d0 MD	510
2dfda770	511	WARN_ON_ONCE(!event_desc);
07dfc1d0	512
60206944 FD	513	/* Go over all the bytecode programs of the enabler. */
60206944 FD	514	list_for_each_entry(enabler_bc, enabler_bytecode_head, node) {
07dfc1d0 MD	515	int found = 0, ret;
	516	struct list_head *insert_loc;
	517
60206944 FD	518	/*
	519	* Check if the current enabler bytecode program is already
	520	* linked with the instance.
	521	*/
	522	list_for_each_entry(runtime, instance_bytecode_head, node) {
	523	if (runtime->bc == enabler_bc) {
07dfc1d0 MD	524	found = 1;
	525	break;
	526	}
	527	}
60206944 FD	528
	529	/*
	530	* Skip bytecode already linked, go to the next enabler
	531	* bytecode program.
	532	*/
07dfc1d0 MD	533	if (found)
	534	continue;
	535
	536	/*
	537	* Insert at specified priority (seqnum) in increasing
df9d0220 FD	538	* order. If there already is a bytecode of the same priority,
df9d0220 FD	539	* insert the new bytecode right after it.
07dfc1d0 MD	540	*/
07dfc1d0 MD	541	list_for_each_entry_reverse(runtime,
60206944 FD	542	instance_bytecode_head, node) {
60206944 FD	543	if (runtime->bc->bc.seqnum <= enabler_bc->bc.seqnum) {
07dfc1d0 MD	544	/* insert here */
	545	insert_loc = &runtime->node;
	546	goto add_within;
	547	}
	548	}
	549	/* Add to head to list */
60206944	550	insert_loc = instance_bytecode_head;
07dfc1d0 MD	551	add_within:
07dfc1d0 MD	552	dbg_printk("linking bytecode\n");
60206944	553	ret = link_bytecode(event_desc, ctx, enabler_bc, insert_loc);
07dfc1d0 MD	554	if (ret) {
	555	dbg_printk("[lttng filter] warning: cannot link event bytecode\n");
	556	}
	557	}
	558	}
	559
	560	/*
	561	* We own the filter_bytecode if we return success.
	562	*/
	563	int lttng_filter_enabler_attach_bytecode(struct lttng_enabler *enabler,
89ec2b91	564	struct lttng_bytecode_node *filter_bytecode)
07dfc1d0 MD	565	{
	566	list_add(&filter_bytecode->node, &enabler->filter_bytecode_head);
	567	return 0;
	568	}
	569
	570	void lttng_free_enabler_filter_bytecode(struct lttng_enabler *enabler)
	571	{
89ec2b91	572	struct lttng_bytecode_node filter_bytecode, tmp;
07dfc1d0 MD	573
	574	list_for_each_entry_safe(filter_bytecode, tmp,
	575	&enabler->filter_bytecode_head, node) {
	576	kfree(filter_bytecode);
	577	}
	578	}
	579
	580	void lttng_free_event_filter_runtime(struct lttng_event *event)
	581	{
	582	struct bytecode_runtime runtime, tmp;
	583
	584	list_for_each_entry_safe(runtime, tmp,
183e8b3a	585	&event->filter_bytecode_runtime_head, p.node) {
3834b99f	586	kfree(runtime->data);
07dfc1d0 MD	587	kfree(runtime);
	588	}
	589	}