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
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
|
/*
* Common header file for probe-based Dynamic events.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* This code was copied from kernel/trace/trace_kprobe.h written by
* Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
*
* Updates to make this generic:
* Copyright (C) IBM Corporation, 2010-2011
* Author: Srikar Dronamraju
*/
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/smp.h>
#include <linux/debugfs.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/ptrace.h>
#include <linux/perf_event.h>
#include <linux/kprobes.h>
#include <linux/stringify.h>
#include <linux/limits.h>
#include <linux/uaccess.h>
#include <asm/bitsperlong.h>
#include "trace.h"
#include "trace_output.h"
#define MAX_TRACE_ARGS 128
#define MAX_ARGSTR_LEN 63
#define MAX_EVENT_NAME_LEN 64
#define MAX_STRING_SIZE PATH_MAX
/* Reserved field names */
#define FIELD_STRING_IP "__probe_ip"
#define FIELD_STRING_RETIP "__probe_ret_ip"
#define FIELD_STRING_FUNC "__probe_func"
#undef DEFINE_FIELD
#define DEFINE_FIELD(type, item, name, is_signed) \
do { \
ret = trace_define_field(event_call, #type, name, \
offsetof(typeof(field), item), \
sizeof(field.item), is_signed, \
FILTER_OTHER); \
if (ret) \
return ret; \
} while (0)
/* Flags for trace_probe */
#define TP_FLAG_TRACE 1
#define TP_FLAG_PROFILE 2
#define TP_FLAG_REGISTERED 4
/* data_rloc: data relative location, compatible with u32 */
#define make_data_rloc(len, roffs) \
(((u32)(len) << 16) | ((u32)(roffs) & 0xffff))
#define get_rloc_len(dl) ((u32)(dl) >> 16)
#define get_rloc_offs(dl) ((u32)(dl) & 0xffff)
/*
* Convert data_rloc to data_loc:
* data_rloc stores the offset from data_rloc itself, but data_loc
* stores the offset from event entry.
*/
#define convert_rloc_to_loc(dl, offs) ((u32)(dl) + (offs))
/* Data fetch function type */
typedef void (*fetch_func_t)(struct pt_regs *, void *, void *);
/* Printing function type */
typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *, void *);
/* Fetch types */
enum {
FETCH_MTD_reg = 0,
FETCH_MTD_stack,
FETCH_MTD_retval,
FETCH_MTD_memory,
FETCH_MTD_symbol,
FETCH_MTD_deref,
FETCH_MTD_bitfield,
FETCH_MTD_END,
};
/* Fetch type information table */
struct fetch_type {
const char *name; /* Name of type */
size_t size; /* Byte size of type */
int is_signed; /* Signed flag */
print_type_func_t print; /* Print functions */
const char *fmt; /* Fromat string */
const char *fmttype; /* Name in format file */
/* Fetch functions */
fetch_func_t fetch[FETCH_MTD_END];
};
struct fetch_param {
fetch_func_t fn;
void *data;
};
struct probe_arg {
struct fetch_param fetch;
struct fetch_param fetch_size;
unsigned int offset; /* Offset from argument entry */
const char *name; /* Name of this argument */
const char *comm; /* Command of this argument */
const struct fetch_type *type; /* Type of this argument */
};
struct trace_probe {
unsigned int flags; /* For TP_FLAG_* */
struct ftrace_event_class class;
struct ftrace_event_call call;
struct list_head files;
ssize_t size; /* trace entry size */
unsigned int nr_args;
struct probe_arg args[];
};
static inline bool trace_probe_is_enabled(struct trace_probe *tp)
{
return !!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE));
}
static inline bool trace_probe_is_registered(struct trace_probe *tp)
{
return !!(tp->flags & TP_FLAG_REGISTERED);
}
static inline __kprobes void call_fetch(struct fetch_param *fprm,
struct pt_regs *regs, void *dest)
{
return fprm->fn(regs, fprm->data, dest);
}
/* Check the name is good for event/group/fields */
static inline int is_good_name(const char *name)
{
if (!isalpha(*name) && *name != '_')
return 0;
while (*++name != '\0') {
if (!isalpha(*name) && !isdigit(*name) && *name != '_')
return 0;
}
return 1;
}
extern int traceprobe_parse_probe_arg(char *arg, ssize_t *size,
struct probe_arg *parg, bool is_return, bool is_kprobe);
extern int traceprobe_conflict_field_name(const char *name,
struct probe_arg *args, int narg);
extern void traceprobe_update_arg(struct probe_arg *arg);
extern void traceprobe_free_probe_arg(struct probe_arg *arg);
extern int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset);
extern ssize_t traceprobe_probes_write(struct file *file,
const char __user *buffer, size_t count, loff_t *ppos,
int (*createfn)(int, char**));
extern int traceprobe_command(const char *buf, int (*createfn)(int, char**));
/* Sum up total data length for dynamic arraies (strings) */
static inline __kprobes int
__get_data_size(struct trace_probe *tp, struct pt_regs *regs)
{
int i, ret = 0;
u32 len;
for (i = 0; i < tp->nr_args; i++)
if (unlikely(tp->args[i].fetch_size.fn)) {
call_fetch(&tp->args[i].fetch_size, regs, &len);
ret += len;
}
return ret;
}
/* Store the value of each argument */
static inline __kprobes void
store_trace_args(int ent_size, struct trace_probe *tp, struct pt_regs *regs,
u8 *data, int maxlen)
{
int i;
u32 end = tp->size;
u32 *dl; /* Data (relative) location */
for (i = 0; i < tp->nr_args; i++) {
if (unlikely(tp->args[i].fetch_size.fn)) {
/*
* First, we set the relative location and
* maximum data length to *dl
*/
dl = (u32 *)(data + tp->args[i].offset);
*dl = make_data_rloc(maxlen, end - tp->args[i].offset);
/* Then try to fetch string or dynamic array data */
call_fetch(&tp->args[i].fetch, regs, dl);
/* Reduce maximum length */
end += get_rloc_len(*dl);
maxlen -= get_rloc_len(*dl);
/* Trick here, convert data_rloc to data_loc */
*dl = convert_rloc_to_loc(*dl,
ent_size + tp->args[i].offset);
} else
/* Just fetching data normally */
call_fetch(&tp->args[i].fetch, regs,
data + tp->args[i].offset);
}
}
|
