1 /* SPDX-License-Identifier: GPL-2.0 */
2 
3 #undef TRACE_SYSTEM_VAR
4 
5 #ifdef CONFIG_BPF_EVENTS
6 
7 #undef __entry
8 #define __entry entry
9 
10 #undef __get_dynamic_array
11 #define __get_dynamic_array(field)	\
12 		((void *)__entry + (__entry->__data_loc_##field & 0xffff))
13 
14 #undef __get_dynamic_array_len
15 #define __get_dynamic_array_len(field)	\
16 		((__entry->__data_loc_##field >> 16) & 0xffff)
17 
18 #undef __get_str
19 #define __get_str(field) ((char *)__get_dynamic_array(field))
20 
21 #undef __get_bitmask
22 #define __get_bitmask(field) (char *)__get_dynamic_array(field)
23 
24 #undef __get_sockaddr
25 #define __get_sockaddr(field) ((struct sockaddr *)__get_dynamic_array(field))
26 
27 #undef __get_rel_dynamic_array
28 #define __get_rel_dynamic_array(field)	\
29 		((void *)(&__entry->__rel_loc_##field) +	\
30 		 sizeof(__entry->__rel_loc_##field) +		\
31 		 (__entry->__rel_loc_##field & 0xffff))
32 
33 #undef __get_rel_dynamic_array_len
34 #define __get_rel_dynamic_array_len(field)	\
35 		((__entry->__rel_loc_##field >> 16) & 0xffff)
36 
37 #undef __get_rel_str
38 #define __get_rel_str(field) ((char *)__get_rel_dynamic_array(field))
39 
40 #undef __get_rel_bitmask
41 #define __get_rel_bitmask(field) (char *)__get_rel_dynamic_array(field)
42 
43 #undef __get_rel_sockaddr
44 #define __get_rel_sockaddr(field) ((struct sockaddr *)__get_rel_dynamic_array(field))
45 
46 #undef __perf_count
47 #define __perf_count(c)	(c)
48 
49 #undef __perf_task
50 #define __perf_task(t)	(t)
51 
52 /* cast any integer, pointer, or small struct to u64 */
53 #define UINTTYPE(size) \
54 	__typeof__(__builtin_choose_expr(size == 1,  (u8)1, \
55 		   __builtin_choose_expr(size == 2, (u16)2, \
56 		   __builtin_choose_expr(size == 4, (u32)3, \
57 		   __builtin_choose_expr(size == 8, (u64)4, \
58 					 (void)5)))))
59 #define __CAST_TO_U64(x) ({ \
60 	typeof(x) __src = (x); \
61 	UINTTYPE(sizeof(x)) __dst; \
62 	memcpy(&__dst, &__src, sizeof(__dst)); \
63 	(u64)__dst; })
64 
65 #define __CAST1(a,...) __CAST_TO_U64(a)
66 #define __CAST2(a,...) __CAST_TO_U64(a), __CAST1(__VA_ARGS__)
67 #define __CAST3(a,...) __CAST_TO_U64(a), __CAST2(__VA_ARGS__)
68 #define __CAST4(a,...) __CAST_TO_U64(a), __CAST3(__VA_ARGS__)
69 #define __CAST5(a,...) __CAST_TO_U64(a), __CAST4(__VA_ARGS__)
70 #define __CAST6(a,...) __CAST_TO_U64(a), __CAST5(__VA_ARGS__)
71 #define __CAST7(a,...) __CAST_TO_U64(a), __CAST6(__VA_ARGS__)
72 #define __CAST8(a,...) __CAST_TO_U64(a), __CAST7(__VA_ARGS__)
73 #define __CAST9(a,...) __CAST_TO_U64(a), __CAST8(__VA_ARGS__)
74 #define __CAST10(a,...) __CAST_TO_U64(a), __CAST9(__VA_ARGS__)
75 #define __CAST11(a,...) __CAST_TO_U64(a), __CAST10(__VA_ARGS__)
76 #define __CAST12(a,...) __CAST_TO_U64(a), __CAST11(__VA_ARGS__)
77 /* tracepoints with more than 12 arguments will hit build error */
78 #define CAST_TO_U64(...) CONCATENATE(__CAST, COUNT_ARGS(__VA_ARGS__))(__VA_ARGS__)
79 
80 #define __BPF_DECLARE_TRACE(call, proto, args)				\
81 static notrace void							\
82 __bpf_trace_##call(void *__data, proto)					\
83 {									\
84 	struct bpf_prog *prog = __data;					\
85 	CONCATENATE(bpf_trace_run, COUNT_ARGS(args))(prog, CAST_TO_U64(args));	\
86 }
87 
88 #undef DECLARE_EVENT_CLASS
89 #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
90 	__BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args))
91 
92 /*
93  * This part is compiled out, it is only here as a build time check
94  * to make sure that if the tracepoint handling changes, the
95  * bpf probe will fail to compile unless it too is updated.
96  */
97 #define __DEFINE_EVENT(template, call, proto, args, size)		\
98 static inline void bpf_test_probe_##call(void)				\
99 {									\
100 	check_trace_callback_type_##call(__bpf_trace_##template);	\
101 }									\
102 typedef void (*btf_trace_##call)(void *__data, proto);			\
103 static union {								\
104 	struct bpf_raw_event_map event;					\
105 	btf_trace_##call handler;					\
106 } __bpf_trace_tp_map_##call __used					\
107 __section("__bpf_raw_tp_map") = {					\
108 	.event = {							\
109 		.tp		= &__tracepoint_##call,			\
110 		.bpf_func	= __bpf_trace_##template,		\
111 		.num_args	= COUNT_ARGS(args),			\
112 		.writable_size	= size,					\
113 	},								\
114 };
115 
116 #define FIRST(x, ...) x
117 
118 #define __CHECK_WRITABLE_BUF_SIZE(call, proto, args, size)		\
119 static inline void bpf_test_buffer_##call(void)				\
120 {									\
121 	/* BUILD_BUG_ON() is ignored if the code is completely eliminated, but \
122 	 * BUILD_BUG_ON_ZERO() uses a different mechanism that is not	\
123 	 * dead-code-eliminated.					\
124 	 */								\
125 	FIRST(proto);							\
126 	(void)BUILD_BUG_ON_ZERO(size != sizeof(*FIRST(args)));		\
127 }
128 
129 #undef DEFINE_EVENT_WRITABLE
130 #define DEFINE_EVENT_WRITABLE(template, call, proto, args, size) \
131 	__CHECK_WRITABLE_BUF_SIZE(call, PARAMS(proto), PARAMS(args), size) \
132 	__DEFINE_EVENT(template, call, PARAMS(proto), PARAMS(args), size)
133 
134 #undef DEFINE_EVENT
135 #define DEFINE_EVENT(template, call, proto, args)			\
136 	__DEFINE_EVENT(template, call, PARAMS(proto), PARAMS(args), 0)
137 
138 #undef DEFINE_EVENT_PRINT
139 #define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
140 	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))
141 
142 #undef DECLARE_TRACE
143 #define DECLARE_TRACE(call, proto, args)				\
144 	__BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args))		\
145 	__DEFINE_EVENT(call, call, PARAMS(proto), PARAMS(args), 0)
146 
147 #undef DECLARE_TRACE_WRITABLE
148 #define DECLARE_TRACE_WRITABLE(call, proto, args, size) \
149 	__CHECK_WRITABLE_BUF_SIZE(call, PARAMS(proto), PARAMS(args), size) \
150 	__BPF_DECLARE_TRACE(call, PARAMS(proto), PARAMS(args)) \
151 	__DEFINE_EVENT(call, call, PARAMS(proto), PARAMS(args), size)
152 
153 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
154 
155 #undef DECLARE_TRACE_WRITABLE
156 #undef DEFINE_EVENT_WRITABLE
157 #undef __CHECK_WRITABLE_BUF_SIZE
158 #undef __DEFINE_EVENT
159 #undef FIRST
160 
161 #endif /* CONFIG_BPF_EVENTS */
162