1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
|
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_TRACE_SEQ_H
#define _LINUX_TRACE_SEQ_H
#include <linux/seq_buf.h>
#include <asm/page.h>
/*
* Trace sequences are used to allow a function to call several other functions
* to create a string of data to use (up to a max of PAGE_SIZE).
*/
struct trace_seq {
unsigned char buffer[PAGE_SIZE];
struct seq_buf seq;
int full;
};
static inline void
trace_seq_init(struct trace_seq *s)
{
seq_buf_init(&s->seq, s->buffer, PAGE_SIZE);
s->full = 0;
}
/**
* trace_seq_used - amount of actual data written to buffer
* @s: trace sequence descriptor
*
* Returns the amount of data written to the buffer.
*
* IMPORTANT!
*
* Use this instead of @s->seq.len if you need to pass the amount
* of data from the buffer to another buffer (userspace, or what not).
* The @s->seq.len on overflow is bigger than the buffer size and
* using it can cause access to undefined memory.
*/
static inline int trace_seq_used(struct trace_seq *s)
{
return seq_buf_used(&s->seq);
}
/**
* trace_seq_buffer_ptr - return pointer to next location in buffer
* @s: trace sequence descriptor
*
* Returns the pointer to the buffer where the next write to
* the buffer will happen. This is useful to save the location
* that is about to be written to and then return the result
* of that write.
*/
static inline unsigned char *
trace_seq_buffer_ptr(struct trace_seq *s)
{
return s->buffer + seq_buf_used(&s->seq);
}
/**
* trace_seq_has_overflowed - return true if the trace_seq took too much
* @s: trace sequence descriptor
*
* Returns true if too much data was added to the trace_seq and it is
* now full and will not take anymore.
*/
static inline bool trace_seq_has_overflowed(struct trace_seq *s)
{
return s->full || seq_buf_has_overflowed(&s->seq);
}
/*
* Currently only defined when tracing is enabled.
*/
#ifdef CONFIG_TRACING
extern __printf(2, 3)
void trace_seq_printf(struct trace_seq *s, const char *fmt, ...);
extern __printf(2, 0)
void trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args);
extern void
trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary);
extern int trace_print_seq(struct seq_file *m, struct trace_seq *s);
extern int trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
int cnt);
extern void trace_seq_puts(struct trace_seq *s, const char *str);
extern void trace_seq_putc(struct trace_seq *s, unsigned char c);
extern void trace_seq_putmem(struct trace_seq *s, const void *mem, unsigned int len);
extern void trace_seq_putmem_hex(struct trace_seq *s, const void *mem,
unsigned int len);
extern int trace_seq_path(struct trace_seq *s, const struct path *path);
extern void trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp,
int nmaskbits);
extern int trace_seq_hex_dump(struct trace_seq *s, const char *prefix_str,
int prefix_type, int rowsize, int groupsize,
const void *buf, size_t len, bool ascii);
#else /* CONFIG_TRACING */
static inline void trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
{
}
static inline void
trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
{
}
static inline void
trace_seq_bitmask(struct trace_seq *s, const unsigned long *maskp,
int nmaskbits)
{
}
static inline int trace_print_seq(struct seq_file *m, struct trace_seq *s)
{
return 0;
}
static inline int trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
int cnt)
{
return 0;
}
static inline void trace_seq_puts(struct trace_seq *s, const char *str)
{
}
static inline void trace_seq_putc(struct trace_seq *s, unsigned char c)
{
}
static inline void
trace_seq_putmem(struct trace_seq *s, const void *mem, unsigned int len)
{
}
static inline void trace_seq_putmem_hex(struct trace_seq *s, const void *mem,
unsigned int len)
{
}
static inline int trace_seq_path(struct trace_seq *s, const struct path *path)
{
return 0;
}
#endif /* CONFIG_TRACING */
#endif /* _LINUX_TRACE_SEQ_H */
|
