[linux-block.git] / include / trace / bpf_probe.h

/* SPDX-License-Identifier: GPL-2.0 */

#undef TRACE_SYSTEM_VAR

#ifdef CONFIG_BPF_EVENTS

#include "stages/stage6_event_callback.h"

#undef __perf_count
#define __perf_count(c)	(c)

#undef __perf_task
#define __perf_task(t)	(t)

/* cast any integer, pointer, or small struct to u64 */
#define UINTTYPE(size) \
	__typeof__(__builtin_choose_expr(size == 1,  (u8)1, \
		   __builtin_choose_expr(size == 2, (u16)2, \
		   __builtin_choose_expr(size == 4, (u32)3, \
		   __builtin_choose_expr(size == 8, (u64)4, \
					 (void)5)))))
#define __CAST_TO_U64(x) ({ \
	typeof(x) __src = (x); \
	UINTTYPE(sizeof(x)) __dst; \
	memcpy(&__dst, &__src, sizeof(__dst)); \
	(u64)__dst; })

#define __CAST1(a,...) __CAST_TO_U64(a)
#define __CAST2(a,...) __CAST_TO_U64(a), __CAST1(__VA_ARGS__)
#define __CAST3(a,...) __CAST_TO_U64(a), __CAST2(__VA_ARGS__)
#define __CAST4(a,...) __CAST_TO_U64(a), __CAST3(__VA_ARGS__)
#define __CAST5(a,...) __CAST_TO_U64(a), __CAST4(__VA_ARGS__)
#define __CAST6(a,...) __CAST_TO_U64(a), __CAST5(__VA_ARGS__)
#define __CAST7(a,...) __CAST_TO_U64(a), __CAST6(__VA_ARGS__)
#define __CAST8(a,...) __CAST_TO_U64(a), __CAST7(__VA_ARGS__)
#define __CAST9(a,...) __CAST_TO_U64(a), __CAST8(__VA_ARGS__)
#define __CAST10(a,...) __CAST_TO_U64(a), __CAST9(__VA_ARGS__)
#define __CAST11(a,...) __CAST_TO_U64(a), __CAST10(__VA_ARGS__)
#define __CAST12(a,...) __CAST_TO_U64(a), __CAST11(__VA_ARGS__)
/* tracepoints with more than 12 arguments will hit build error */
#define CAST_TO_U64(...) CONCATENATE(__CAST, COUNT_ARGS(__VA_ARGS__))(__VA_ARGS__)

#define __BPF_DECLARE_TRACE(call, proto, args)				\
static notrace void							\
__bpf_trace_##call(void *__data, proto)					\
{									\
	struct bpf_prog *prog = __data;					\
	CONCATENATE(bpf_trace_run, COUNT_ARGS(args))(prog, CAST_TO_U64(args));	\
}

#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
	__BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args))

/*
 * This part is compiled out, it is only here as a build time check
 * to make sure that if the tracepoint handling changes, the
 * bpf probe will fail to compile unless it too is updated.
 */
#define __DEFINE_EVENT(template, call, proto, args, size)		\
static inline void bpf_test_probe_##call(void)				\
{									\
	check_trace_callback_type_##call(__bpf_trace_##template);	\
}									\
typedef void (*btf_trace_##call)(void *__data, proto);			\
static union {								\
	struct bpf_raw_event_map event;					\
	btf_trace_##call handler;					\
} __bpf_trace_tp_map_##call __used					\
__section("__bpf_raw_tp_map") = {					\
	.event = {							\
		.tp		= &__tracepoint_##call,			\
		.bpf_func	= __bpf_trace_##template,		\
		.num_args	= COUNT_ARGS(args),			\
		.writable_size	= size,					\
	},								\
};

#define FIRST(x, ...) x

#define __CHECK_WRITABLE_BUF_SIZE(call, proto, args, size)		\
static inline void bpf_test_buffer_##call(void)				\
{									\
	/* BUILD_BUG_ON() is ignored if the code is completely eliminated, but \
	 * BUILD_BUG_ON_ZERO() uses a different mechanism that is not	\
	 * dead-code-eliminated.					\
	 */								\
	FIRST(proto);							\
	(void)BUILD_BUG_ON_ZERO(size != sizeof(*FIRST(args)));		\
}

#undef DEFINE_EVENT_WRITABLE
#define DEFINE_EVENT_WRITABLE(template, call, proto, args, size) \
	__CHECK_WRITABLE_BUF_SIZE(call, PARAMS(proto), PARAMS(args), size) \
	__DEFINE_EVENT(template, call, PARAMS(proto), PARAMS(args), size)

#undef DEFINE_EVENT
#define DEFINE_EVENT(template, call, proto, args)			\
	__DEFINE_EVENT(template, call, PARAMS(proto), PARAMS(args), 0)

#undef DEFINE_EVENT_PRINT
#define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))

#undef DECLARE_TRACE
#define DECLARE_TRACE(call, proto, args)				\
	__BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args))		\
	__DEFINE_EVENT(call, call, PARAMS(proto), PARAMS(args), 0)

#undef DECLARE_TRACE_WRITABLE
#define DECLARE_TRACE_WRITABLE(call, proto, args, size) \
	__CHECK_WRITABLE_BUF_SIZE(call, PARAMS(proto), PARAMS(args), size) \
	__BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args)) \
	__DEFINE_EVENT(call, call, PARAMS(proto), PARAMS(args), size)

#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

#undef DECLARE_TRACE_WRITABLE
#undef DEFINE_EVENT_WRITABLE
#undef __CHECK_WRITABLE_BUF_SIZE
#undef __DEFINE_EVENT
#undef FIRST

#endif /* CONFIG_BPF_EVENTS */
Commit	Line	Data
c4f6699d AS	1	/* SPDX-License-Identifier: GPL-2.0 */
	2
	3	#undef TRACE_SYSTEM_VAR
	4
	5	#ifdef CONFIG_BPF_EVENTS
	6
dc513fd5	7	#include "stages/stage6_event_callback.h"
d07c9ad6	8
c4f6699d AS	9	#undef __perf_count
	10	#define __perf_count(c) (c)
	11
	12	#undef __perf_task
	13	#define __perf_task(t) (t)
	14
	15	/* cast any integer, pointer, or small struct to u64 */
	16	#define UINTTYPE(size) \
	17	__typeof__(__builtin_choose_expr(size == 1, (u8)1, \
	18	__builtin_choose_expr(size == 2, (u16)2, \
	19	__builtin_choose_expr(size == 4, (u32)3, \
	20	__builtin_choose_expr(size == 8, (u64)4, \
	21	(void)5)))))
	22	#define __CAST_TO_U64(x) ({ \
	23	typeof(x) __src = (x); \
	24	UINTTYPE(sizeof(x)) __dst; \
	25	memcpy(&__dst, &__src, sizeof(__dst)); \
	26	(u64)__dst; })
	27
	28	#define __CAST1(a,...) __CAST_TO_U64(a)
	29	#define __CAST2(a,...) __CAST_TO_U64(a), __CAST1(__VA_ARGS__)
	30	#define __CAST3(a,...) __CAST_TO_U64(a), __CAST2(__VA_ARGS__)
	31	#define __CAST4(a,...) __CAST_TO_U64(a), __CAST3(__VA_ARGS__)
	32	#define __CAST5(a,...) __CAST_TO_U64(a), __CAST4(__VA_ARGS__)
	33	#define __CAST6(a,...) __CAST_TO_U64(a), __CAST5(__VA_ARGS__)
	34	#define __CAST7(a,...) __CAST_TO_U64(a), __CAST6(__VA_ARGS__)
	35	#define __CAST8(a,...) __CAST_TO_U64(a), __CAST7(__VA_ARGS__)
	36	#define __CAST9(a,...) __CAST_TO_U64(a), __CAST8(__VA_ARGS__)
	37	#define __CAST10(a,...) __CAST_TO_U64(a), __CAST9(__VA_ARGS__)
	38	#define __CAST11(a,...) __CAST_TO_U64(a), __CAST10(__VA_ARGS__)
	39	#define __CAST12(a,...) __CAST_TO_U64(a), __CAST11(__VA_ARGS__)
	40	/* tracepoints with more than 12 arguments will hit build error */
	41	#define CAST_TO_U64(...) CONCATENATE(__CAST, COUNT_ARGS(__VA_ARGS__))(__VA_ARGS__)
	42
6939f4ef	43	#define __BPF_DECLARE_TRACE(call, proto, args) \
c4f6699d AS	44	static notrace void \
	45	__bpf_trace_##call(void *__data, proto) \
	46	{ \
	47	struct bpf_prog *prog = __data; \
	48	CONCATENATE(bpf_trace_run, COUNT_ARGS(args))(prog, CAST_TO_U64(args)); \
	49	}
	50
6939f4ef QY	51	#undef DECLARE_EVENT_CLASS
	52	#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print) \
	53	__BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args))
	54
c4f6699d AS	55	/*
	56	* This part is compiled out, it is only here as a build time check
	57	* to make sure that if the tracepoint handling changes, the
	58	* bpf probe will fail to compile unless it too is updated.
	59	*/
9df1c28b	60	#define __DEFINE_EVENT(template, call, proto, args, size) \
c4f6699d AS	61	static inline void bpf_test_probe_##call(void) \
	62	{ \
	63	check_trace_callback_type_##call(__bpf_trace_##template); \
	64	} \
e8c423fb	65	typedef void (btf_trace_##call)(void __data, proto); \
441420a1 AN	66	static union { \
	67	struct bpf_raw_event_map event; \
	68	btf_trace_##call handler; \
	69	} __bpf_trace_tp_map_##call __used \
33def849	70	__section("__bpf_raw_tp_map") = { \
441420a1 AN	71	.event = { \
	72	.tp = &__tracepoint_##call, \
	73	.bpf_func = __bpf_trace_##template, \
	74	.num_args = COUNT_ARGS(args), \
	75	.writable_size = size, \
	76	}, \
c4f6699d AS	77	};
c4f6699d AS	78
9df1c28b MM	79	#define FIRST(x, ...) x
9df1c28b MM	80
65223741	81	#define __CHECK_WRITABLE_BUF_SIZE(call, proto, args, size) \
9df1c28b MM	82	static inline void bpf_test_buffer_##call(void) \
	83	{ \
	84	/* BUILD_BUG_ON() is ignored if the code is completely eliminated, but \
	85	* BUILD_BUG_ON_ZERO() uses a different mechanism that is not \
	86	* dead-code-eliminated. \
	87	*/ \
	88	FIRST(proto); \
	89	(void)BUILD_BUG_ON_ZERO(size != sizeof(*FIRST(args))); \
65223741 HT	90	}
	91
	92	#undef DEFINE_EVENT_WRITABLE
	93	#define DEFINE_EVENT_WRITABLE(template, call, proto, args, size) \
	94	__CHECK_WRITABLE_BUF_SIZE(call, PARAMS(proto), PARAMS(args), size) \
	95	__DEFINE_EVENT(template, call, PARAMS(proto), PARAMS(args), size)
9df1c28b MM	96
	97	#undef DEFINE_EVENT
	98	#define DEFINE_EVENT(template, call, proto, args) \
	99	__DEFINE_EVENT(template, call, PARAMS(proto), PARAMS(args), 0)
c4f6699d AS	100
	101	#undef DEFINE_EVENT_PRINT
	102	#define DEFINE_EVENT_PRINT(template, name, proto, args, print) \
	103	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))
	104
6939f4ef QY	105	#undef DECLARE_TRACE
	106	#define DECLARE_TRACE(call, proto, args) \
	107	__BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args)) \
	108	__DEFINE_EVENT(call, call, PARAMS(proto), PARAMS(args), 0)
	109
65223741 HT	110	#undef DECLARE_TRACE_WRITABLE
	111	#define DECLARE_TRACE_WRITABLE(call, proto, args, size) \
	112	__CHECK_WRITABLE_BUF_SIZE(call, PARAMS(proto), PARAMS(args), size) \
	113	__BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args)) \
	114	__DEFINE_EVENT(call, call, PARAMS(proto), PARAMS(args), size)
	115
c4f6699d	116	#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
9df1c28b	117
65223741	118	#undef DECLARE_TRACE_WRITABLE
9df1c28b	119	#undef DEFINE_EVENT_WRITABLE
65223741	120	#undef __CHECK_WRITABLE_BUF_SIZE
9df1c28b MM	121	#undef __DEFINE_EVENT
	122	#undef FIRST
	123
c4f6699d	124	#endif /* CONFIG_BPF_EVENTS */