1/* SPDX-License-Identifier: GPL-2.0 */
2
3#undef TRACE_SYSTEM_VAR
4
5#ifdef CONFIG_BPF_EVENTS
6
7#include "stages/stage6_event_callback.h"
8
9#undef __perf_count
10#define __perf_count(c)	(c)
11
12#undef __perf_task
13#define __perf_task(t)	(t)
14
15#include <linux/args.h>
16
17/* cast any integer, pointer, or small struct to u64 */
18#define UINTTYPE(size) \
19	__typeof__(__builtin_choose_expr(size == 1,  (u8)1, \
20		   __builtin_choose_expr(size == 2, (u16)2, \
21		   __builtin_choose_expr(size == 4, (u32)3, \
22		   __builtin_choose_expr(size == 8, (u64)4, \
23					 (void)5)))))
24#define __CAST_TO_U64(x) ({ \
25	typeof(x) __src = (x); \
26	UINTTYPE(sizeof(x)) __dst; \
27	memcpy(&__dst, &__src, sizeof(__dst)); \
28	(u64)__dst; })
29
30#define __CAST1(a,...) __CAST_TO_U64(a)
31#define __CAST2(a,...) __CAST_TO_U64(a), __CAST1(__VA_ARGS__)
32#define __CAST3(a,...) __CAST_TO_U64(a), __CAST2(__VA_ARGS__)
33#define __CAST4(a,...) __CAST_TO_U64(a), __CAST3(__VA_ARGS__)
34#define __CAST5(a,...) __CAST_TO_U64(a), __CAST4(__VA_ARGS__)
35#define __CAST6(a,...) __CAST_TO_U64(a), __CAST5(__VA_ARGS__)
36#define __CAST7(a,...) __CAST_TO_U64(a), __CAST6(__VA_ARGS__)
37#define __CAST8(a,...) __CAST_TO_U64(a), __CAST7(__VA_ARGS__)
38#define __CAST9(a,...) __CAST_TO_U64(a), __CAST8(__VA_ARGS__)
39#define __CAST10(a,...) __CAST_TO_U64(a), __CAST9(__VA_ARGS__)
40#define __CAST11(a,...) __CAST_TO_U64(a), __CAST10(__VA_ARGS__)
41#define __CAST12(a,...) __CAST_TO_U64(a), __CAST11(__VA_ARGS__)
42/* tracepoints with more than 12 arguments will hit build error */
43#define CAST_TO_U64(...) CONCATENATE(__CAST, COUNT_ARGS(__VA_ARGS__))(__VA_ARGS__)
44
45#define __BPF_DECLARE_TRACE(call, proto, args)				\
46static notrace void							\
47__bpf_trace_##call(void *__data, proto)					\
48{									\
49	struct bpf_prog *prog = __data;					\
50	CONCATENATE(bpf_trace_run, COUNT_ARGS(args))(prog, CAST_TO_U64(args));	\
51}
52
53#undef DECLARE_EVENT_CLASS
54#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
55	__BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args))
56
57/*
58 * This part is compiled out, it is only here as a build time check
59 * to make sure that if the tracepoint handling changes, the
60 * bpf probe will fail to compile unless it too is updated.
61 */
62#define __DEFINE_EVENT(template, call, proto, args, size)		\
63static inline void bpf_test_probe_##call(void)				\
64{									\
65	check_trace_callback_type_##call(__bpf_trace_##template);	\
66}									\
67typedef void (*btf_trace_##call)(void *__data, proto);			\
68static union {								\
69	struct bpf_raw_event_map event;					\
70	btf_trace_##call handler;					\
71} __bpf_trace_tp_map_##call __used					\
72__section("__bpf_raw_tp_map") = {					\
73	.event = {							\
74		.tp		= &__tracepoint_##call,			\
75		.bpf_func	= __bpf_trace_##template,		\
76		.num_args	= COUNT_ARGS(args),			\
77		.writable_size	= size,					\
78	},								\
79};
80
81#define FIRST(x, ...) x
82
83#define __CHECK_WRITABLE_BUF_SIZE(call, proto, args, size)		\
84static inline void bpf_test_buffer_##call(void)				\
85{									\
86	/* BUILD_BUG_ON() is ignored if the code is completely eliminated, but \
87	 * BUILD_BUG_ON_ZERO() uses a different mechanism that is not	\
88	 * dead-code-eliminated.					\
89	 */								\
90	FIRST(proto);							\
91	(void)BUILD_BUG_ON_ZERO(size != sizeof(*FIRST(args)));		\
92}
93
94#undef DEFINE_EVENT_WRITABLE
95#define DEFINE_EVENT_WRITABLE(template, call, proto, args, size) \
96	__CHECK_WRITABLE_BUF_SIZE(call, PARAMS(proto), PARAMS(args), size) \
97	__DEFINE_EVENT(template, call, PARAMS(proto), PARAMS(args), size)
98
99#undef DEFINE_EVENT
100#define DEFINE_EVENT(template, call, proto, args)			\
101	__DEFINE_EVENT(template, call, PARAMS(proto), PARAMS(args), 0)
102
103#undef DEFINE_EVENT_PRINT
104#define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
105	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))
106
107#undef DECLARE_TRACE
108#define DECLARE_TRACE(call, proto, args)				\
109	__BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args))		\
110	__DEFINE_EVENT(call, call, PARAMS(proto), PARAMS(args), 0)
111
112#undef DECLARE_TRACE_WRITABLE
113#define DECLARE_TRACE_WRITABLE(call, proto, args, size) \
114	__CHECK_WRITABLE_BUF_SIZE(call, PARAMS(proto), PARAMS(args), size) \
115	__BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args)) \
116	__DEFINE_EVENT(call, call, PARAMS(proto), PARAMS(args), size)
117
118#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
119
120#undef DECLARE_TRACE_WRITABLE
121#undef DEFINE_EVENT_WRITABLE
122#undef __CHECK_WRITABLE_BUF_SIZE
123#undef __DEFINE_EVENT
124#undef FIRST
125
126#endif /* CONFIG_BPF_EVENTS */
127