xref: /linux-6.15/include/linux/trace_seq.h (revision 36aabfff)
1 #ifndef _LINUX_TRACE_SEQ_H
2 #define _LINUX_TRACE_SEQ_H
3 
4 #include <linux/fs.h>
5 
6 #include <asm/page.h>
7 
8 /*
9  * Trace sequences are used to allow a function to call several other functions
10  * to create a string of data to use (up to a max of PAGE_SIZE).
11  */
12 
13 struct trace_seq {
14 	unsigned char		buffer[PAGE_SIZE];
15 	unsigned int		len;
16 	unsigned int		readpos;
17 	int			full;
18 };
19 
20 static inline void
21 trace_seq_init(struct trace_seq *s)
22 {
23 	s->len = 0;
24 	s->readpos = 0;
25 	s->full = 0;
26 }
27 
28 #define MAX_MEMHEX_BYTES	8
29 
30 /*
31  * Currently only defined when tracing is enabled.
32  */
33 #ifdef CONFIG_TRACING
34 extern __printf(2, 3)
35 int trace_seq_printf(struct trace_seq *s, const char *fmt, ...);
36 extern __printf(2, 0)
37 int trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args);
38 extern int
39 trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary);
40 extern int trace_print_seq(struct seq_file *m, struct trace_seq *s);
41 extern int trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
42 			     int cnt);
43 extern int trace_seq_puts(struct trace_seq *s, const char *str);
44 extern int trace_seq_putc(struct trace_seq *s, unsigned char c);
45 extern int trace_seq_putmem(struct trace_seq *s, const void *mem, unsigned int len);
46 extern int trace_seq_putmem_hex(struct trace_seq *s, const void *mem,
47 				unsigned int len);
48 extern void *trace_seq_reserve(struct trace_seq *s, unsigned int len);
49 extern int trace_seq_path(struct trace_seq *s, const struct path *path);
50 
51 extern int trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp,
52 			     int nmaskbits);
53 
54 #else /* CONFIG_TRACING */
55 static inline int trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
56 {
57 	return 0;
58 }
59 static inline int
60 trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
61 {
62 	return 0;
63 }
64 
65 static inline int
66 trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp,
67 		  int nmaskbits)
68 {
69 	return 0;
70 }
71 
72 static inline int trace_print_seq(struct seq_file *m, struct trace_seq *s)
73 {
74 	return 0;
75 }
76 static inline int trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
77 				    int cnt)
78 {
79 	return 0;
80 }
81 static inline int trace_seq_puts(struct trace_seq *s, const char *str)
82 {
83 	return 0;
84 }
85 static inline int trace_seq_putc(struct trace_seq *s, unsigned char c)
86 {
87 	return 0;
88 }
89 static inline int
90 trace_seq_putmem(struct trace_seq *s, const void *mem, unsigned int len)
91 {
92 	return 0;
93 }
94 static inline int trace_seq_putmem_hex(struct trace_seq *s, const void *mem,
95 				       unsigned int len)
96 {
97 	return 0;
98 }
99 static inline void *trace_seq_reserve(struct trace_seq *s, unsigned int len)
100 {
101 	return NULL;
102 }
103 static inline int trace_seq_path(struct trace_seq *s, const struct path *path)
104 {
105 	return 0;
106 }
107 #endif /* CONFIG_TRACING */
108 
109 #endif /* _LINUX_TRACE_SEQ_H */
110