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1/*
2 * Common header file for probe-based Dynamic events.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software
15 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
16 *
17 * This code was copied from kernel/trace/trace_kprobe.h written by
18 * Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
19 *
20 * Updates to make this generic:
21 * Copyright (C) IBM Corporation, 2010-2011
22 * Author: Srikar Dronamraju
23 */
24
25#include <linux/seq_file.h>
26#include <linux/slab.h>
27#include <linux/smp.h>
28#include <linux/debugfs.h>
29#include <linux/types.h>
30#include <linux/string.h>
31#include <linux/ctype.h>
32#include <linux/ptrace.h>
33#include <linux/perf_event.h>
34#include <linux/kprobes.h>
35#include <linux/stringify.h>
36#include <linux/limits.h>
37#include <linux/uaccess.h>
38#include <asm/bitsperlong.h>
39
40#include "trace.h"
41#include "trace_output.h"
42
43#define MAX_TRACE_ARGS 128
44#define MAX_ARGSTR_LEN 63
45#define MAX_EVENT_NAME_LEN 64
46#define MAX_STRING_SIZE PATH_MAX
47
48/* Reserved field names */
49#define FIELD_STRING_IP "__probe_ip"
50#define FIELD_STRING_RETIP "__probe_ret_ip"
51#define FIELD_STRING_FUNC "__probe_func"
52
53#undef DEFINE_FIELD
54#define DEFINE_FIELD(type, item, name, is_signed) \
55 do { \
56 ret = trace_define_field(event_call, #type, name, \
57 offsetof(typeof(field), item), \
58 sizeof(field.item), is_signed, \
59 FILTER_OTHER); \
60 if (ret) \
61 return ret; \
62 } while (0)
63
64
65/* Flags for trace_probe */
66#define TP_FLAG_TRACE 1
67#define TP_FLAG_PROFILE 2
68#define TP_FLAG_REGISTERED 4
69#define TP_FLAG_UPROBE 8
70
71
72/* data_rloc: data relative location, compatible with u32 */
73#define make_data_rloc(len, roffs) \
74 (((u32)(len) << 16) | ((u32)(roffs) & 0xffff))
75#define get_rloc_len(dl) ((u32)(dl) >> 16)
76#define get_rloc_offs(dl) ((u32)(dl) & 0xffff)
77
78/*
79 * Convert data_rloc to data_loc:
80 * data_rloc stores the offset from data_rloc itself, but data_loc
81 * stores the offset from event entry.
82 */
83#define convert_rloc_to_loc(dl, offs) ((u32)(dl) + (offs))
84
85/* Data fetch function type */
86typedef void (*fetch_func_t)(struct pt_regs *, void *, void *);
87/* Printing function type */
88typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *, void *);
89
90/* Fetch types */
91enum {
92 FETCH_MTD_reg = 0,
93 FETCH_MTD_stack,
94 FETCH_MTD_retval,
95 FETCH_MTD_memory,
96 FETCH_MTD_symbol,
97 FETCH_MTD_deref,
98 FETCH_MTD_bitfield,
99 FETCH_MTD_END,
100};
101
102/* Fetch type information table */
103struct fetch_type {
104 const char *name; /* Name of type */
105 size_t size; /* Byte size of type */
106 int is_signed; /* Signed flag */
107 print_type_func_t print; /* Print functions */
108 const char *fmt; /* Fromat string */
109 const char *fmttype; /* Name in format file */
110 /* Fetch functions */
111 fetch_func_t fetch[FETCH_MTD_END];
112};
113
114struct fetch_param {
115 fetch_func_t fn;
116 void *data;
117};
118
119struct probe_arg {
120 struct fetch_param fetch;
121 struct fetch_param fetch_size;
122 unsigned int offset; /* Offset from argument entry */
123 const char *name; /* Name of this argument */
124 const char *comm; /* Command of this argument */
125 const struct fetch_type *type; /* Type of this argument */
126};
127
128static inline __kprobes void call_fetch(struct fetch_param *fprm,
129 struct pt_regs *regs, void *dest)
130{
131 return fprm->fn(regs, fprm->data, dest);
132}
133
134/* Check the name is good for event/group/fields */
135static inline int is_good_name(const char *name)
136{
137 if (!isalpha(*name) && *name != '_')
138 return 0;
139 while (*++name != '\0') {
140 if (!isalpha(*name) && !isdigit(*name) && *name != '_')
141 return 0;
142 }
143 return 1;
144}
145
146extern int traceprobe_parse_probe_arg(char *arg, ssize_t *size,
147 struct probe_arg *parg, bool is_return, bool is_kprobe);
148
149extern int traceprobe_conflict_field_name(const char *name,
150 struct probe_arg *args, int narg);
151
152extern void traceprobe_update_arg(struct probe_arg *arg);
153extern void traceprobe_free_probe_arg(struct probe_arg *arg);
154
155extern int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset);
156
157extern ssize_t traceprobe_probes_write(struct file *file,
158 const char __user *buffer, size_t count, loff_t *ppos,
159 int (*createfn)(int, char**));
160
161extern int traceprobe_command(const char *buf, int (*createfn)(int, char**));
1/*
2 * Common header file for probe-based Dynamic events.
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software
15 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
16 *
17 * This code was copied from kernel/trace/trace_kprobe.h written by
18 * Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
19 *
20 * Updates to make this generic:
21 * Copyright (C) IBM Corporation, 2010-2011
22 * Author: Srikar Dronamraju
23 */
24
25#include <linux/seq_file.h>
26#include <linux/slab.h>
27#include <linux/smp.h>
28#include <linux/tracefs.h>
29#include <linux/types.h>
30#include <linux/string.h>
31#include <linux/ctype.h>
32#include <linux/ptrace.h>
33#include <linux/perf_event.h>
34#include <linux/kprobes.h>
35#include <linux/stringify.h>
36#include <linux/limits.h>
37#include <linux/uaccess.h>
38#include <asm/bitsperlong.h>
39
40#include "trace.h"
41#include "trace_output.h"
42
43#define MAX_TRACE_ARGS 128
44#define MAX_ARGSTR_LEN 63
45#define MAX_EVENT_NAME_LEN 64
46#define MAX_STRING_SIZE PATH_MAX
47
48/* Reserved field names */
49#define FIELD_STRING_IP "__probe_ip"
50#define FIELD_STRING_RETIP "__probe_ret_ip"
51#define FIELD_STRING_FUNC "__probe_func"
52
53#undef DEFINE_FIELD
54#define DEFINE_FIELD(type, item, name, is_signed) \
55 do { \
56 ret = trace_define_field(event_call, #type, name, \
57 offsetof(typeof(field), item), \
58 sizeof(field.item), is_signed, \
59 FILTER_OTHER); \
60 if (ret) \
61 return ret; \
62 } while (0)
63
64
65/* Flags for trace_probe */
66#define TP_FLAG_TRACE 1
67#define TP_FLAG_PROFILE 2
68#define TP_FLAG_REGISTERED 4
69
70
71/* data_rloc: data relative location, compatible with u32 */
72#define make_data_rloc(len, roffs) \
73 (((u32)(len) << 16) | ((u32)(roffs) & 0xffff))
74#define get_rloc_len(dl) ((u32)(dl) >> 16)
75#define get_rloc_offs(dl) ((u32)(dl) & 0xffff)
76
77/*
78 * Convert data_rloc to data_loc:
79 * data_rloc stores the offset from data_rloc itself, but data_loc
80 * stores the offset from event entry.
81 */
82#define convert_rloc_to_loc(dl, offs) ((u32)(dl) + (offs))
83
84static nokprobe_inline void *get_rloc_data(u32 *dl)
85{
86 return (u8 *)dl + get_rloc_offs(*dl);
87}
88
89/* For data_loc conversion */
90static nokprobe_inline void *get_loc_data(u32 *dl, void *ent)
91{
92 return (u8 *)ent + get_rloc_offs(*dl);
93}
94
95/* Data fetch function type */
96typedef void (*fetch_func_t)(struct pt_regs *, void *, void *);
97/* Printing function type */
98typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *, void *);
99
100/* Fetch types */
101enum {
102 FETCH_MTD_reg = 0,
103 FETCH_MTD_stack,
104 FETCH_MTD_retval,
105 FETCH_MTD_comm,
106 FETCH_MTD_memory,
107 FETCH_MTD_symbol,
108 FETCH_MTD_deref,
109 FETCH_MTD_bitfield,
110 FETCH_MTD_file_offset,
111 FETCH_MTD_END,
112};
113
114/* Fetch type information table */
115struct fetch_type {
116 const char *name; /* Name of type */
117 size_t size; /* Byte size of type */
118 int is_signed; /* Signed flag */
119 print_type_func_t print; /* Print functions */
120 const char *fmt; /* Fromat string */
121 const char *fmttype; /* Name in format file */
122 /* Fetch functions */
123 fetch_func_t fetch[FETCH_MTD_END];
124};
125
126struct fetch_param {
127 fetch_func_t fn;
128 void *data;
129};
130
131/* For defining macros, define string/string_size types */
132typedef u32 string;
133typedef u32 string_size;
134
135#define PRINT_TYPE_FUNC_NAME(type) print_type_##type
136#define PRINT_TYPE_FMT_NAME(type) print_type_format_##type
137
138/* Printing in basic type function template */
139#define DECLARE_BASIC_PRINT_TYPE_FUNC(type) \
140int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, const char *name, \
141 void *data, void *ent); \
142extern const char PRINT_TYPE_FMT_NAME(type)[]
143
144DECLARE_BASIC_PRINT_TYPE_FUNC(u8);
145DECLARE_BASIC_PRINT_TYPE_FUNC(u16);
146DECLARE_BASIC_PRINT_TYPE_FUNC(u32);
147DECLARE_BASIC_PRINT_TYPE_FUNC(u64);
148DECLARE_BASIC_PRINT_TYPE_FUNC(s8);
149DECLARE_BASIC_PRINT_TYPE_FUNC(s16);
150DECLARE_BASIC_PRINT_TYPE_FUNC(s32);
151DECLARE_BASIC_PRINT_TYPE_FUNC(s64);
152DECLARE_BASIC_PRINT_TYPE_FUNC(x8);
153DECLARE_BASIC_PRINT_TYPE_FUNC(x16);
154DECLARE_BASIC_PRINT_TYPE_FUNC(x32);
155DECLARE_BASIC_PRINT_TYPE_FUNC(x64);
156
157DECLARE_BASIC_PRINT_TYPE_FUNC(string);
158
159#define FETCH_FUNC_NAME(method, type) fetch_##method##_##type
160
161/* Declare macro for basic types */
162#define DECLARE_FETCH_FUNC(method, type) \
163extern void FETCH_FUNC_NAME(method, type)(struct pt_regs *regs, \
164 void *data, void *dest)
165
166#define DECLARE_BASIC_FETCH_FUNCS(method) \
167DECLARE_FETCH_FUNC(method, u8); \
168DECLARE_FETCH_FUNC(method, u16); \
169DECLARE_FETCH_FUNC(method, u32); \
170DECLARE_FETCH_FUNC(method, u64)
171
172DECLARE_BASIC_FETCH_FUNCS(reg);
173#define fetch_reg_string NULL
174#define fetch_reg_string_size NULL
175
176DECLARE_BASIC_FETCH_FUNCS(retval);
177#define fetch_retval_string NULL
178#define fetch_retval_string_size NULL
179
180DECLARE_BASIC_FETCH_FUNCS(symbol);
181DECLARE_FETCH_FUNC(symbol, string);
182DECLARE_FETCH_FUNC(symbol, string_size);
183
184DECLARE_BASIC_FETCH_FUNCS(deref);
185DECLARE_FETCH_FUNC(deref, string);
186DECLARE_FETCH_FUNC(deref, string_size);
187
188DECLARE_BASIC_FETCH_FUNCS(bitfield);
189#define fetch_bitfield_string NULL
190#define fetch_bitfield_string_size NULL
191
192/* comm only makes sense as a string */
193#define fetch_comm_u8 NULL
194#define fetch_comm_u16 NULL
195#define fetch_comm_u32 NULL
196#define fetch_comm_u64 NULL
197DECLARE_FETCH_FUNC(comm, string);
198DECLARE_FETCH_FUNC(comm, string_size);
199
200/*
201 * Define macro for basic types - we don't need to define s* types, because
202 * we have to care only about bitwidth at recording time.
203 */
204#define DEFINE_BASIC_FETCH_FUNCS(method) \
205DEFINE_FETCH_##method(u8) \
206DEFINE_FETCH_##method(u16) \
207DEFINE_FETCH_##method(u32) \
208DEFINE_FETCH_##method(u64)
209
210/* Default (unsigned long) fetch type */
211#define __DEFAULT_FETCH_TYPE(t) x##t
212#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)
213#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG)
214#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE)
215
216#define ASSIGN_FETCH_FUNC(method, type) \
217 [FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type)
218
219#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \
220 {.name = _name, \
221 .size = _size, \
222 .is_signed = sign, \
223 .print = PRINT_TYPE_FUNC_NAME(ptype), \
224 .fmt = PRINT_TYPE_FMT_NAME(ptype), \
225 .fmttype = _fmttype, \
226 .fetch = { \
227ASSIGN_FETCH_FUNC(reg, ftype), \
228ASSIGN_FETCH_FUNC(stack, ftype), \
229ASSIGN_FETCH_FUNC(retval, ftype), \
230ASSIGN_FETCH_FUNC(comm, ftype), \
231ASSIGN_FETCH_FUNC(memory, ftype), \
232ASSIGN_FETCH_FUNC(symbol, ftype), \
233ASSIGN_FETCH_FUNC(deref, ftype), \
234ASSIGN_FETCH_FUNC(bitfield, ftype), \
235ASSIGN_FETCH_FUNC(file_offset, ftype), \
236 } \
237 }
238
239#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \
240 __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype)
241
242/* If ptype is an alias of atype, use this macro (show atype in format) */
243#define ASSIGN_FETCH_TYPE_ALIAS(ptype, atype, ftype, sign) \
244 __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #atype)
245
246#define ASSIGN_FETCH_TYPE_END {}
247
248#define FETCH_TYPE_STRING 0
249#define FETCH_TYPE_STRSIZE 1
250
251#ifdef CONFIG_KPROBE_EVENT
252struct symbol_cache;
253unsigned long update_symbol_cache(struct symbol_cache *sc);
254void free_symbol_cache(struct symbol_cache *sc);
255struct symbol_cache *alloc_symbol_cache(const char *sym, long offset);
256#else
257/* uprobes do not support symbol fetch methods */
258#define fetch_symbol_u8 NULL
259#define fetch_symbol_u16 NULL
260#define fetch_symbol_u32 NULL
261#define fetch_symbol_u64 NULL
262#define fetch_symbol_string NULL
263#define fetch_symbol_string_size NULL
264
265struct symbol_cache {
266};
267static inline unsigned long __used update_symbol_cache(struct symbol_cache *sc)
268{
269 return 0;
270}
271
272static inline void __used free_symbol_cache(struct symbol_cache *sc)
273{
274}
275
276static inline struct symbol_cache * __used
277alloc_symbol_cache(const char *sym, long offset)
278{
279 return NULL;
280}
281#endif /* CONFIG_KPROBE_EVENT */
282
283struct probe_arg {
284 struct fetch_param fetch;
285 struct fetch_param fetch_size;
286 unsigned int offset; /* Offset from argument entry */
287 const char *name; /* Name of this argument */
288 const char *comm; /* Command of this argument */
289 const struct fetch_type *type; /* Type of this argument */
290};
291
292struct trace_probe {
293 unsigned int flags; /* For TP_FLAG_* */
294 struct trace_event_class class;
295 struct trace_event_call call;
296 struct list_head files;
297 ssize_t size; /* trace entry size */
298 unsigned int nr_args;
299 struct probe_arg args[];
300};
301
302struct event_file_link {
303 struct trace_event_file *file;
304 struct list_head list;
305};
306
307static inline bool trace_probe_is_enabled(struct trace_probe *tp)
308{
309 return !!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE));
310}
311
312static inline bool trace_probe_is_registered(struct trace_probe *tp)
313{
314 return !!(tp->flags & TP_FLAG_REGISTERED);
315}
316
317static nokprobe_inline void call_fetch(struct fetch_param *fprm,
318 struct pt_regs *regs, void *dest)
319{
320 return fprm->fn(regs, fprm->data, dest);
321}
322
323/* Check the name is good for event/group/fields */
324static inline bool is_good_name(const char *name)
325{
326 if (!isalpha(*name) && *name != '_')
327 return false;
328 while (*++name != '\0') {
329 if (!isalpha(*name) && !isdigit(*name) && *name != '_')
330 return false;
331 }
332 return true;
333}
334
335static inline struct event_file_link *
336find_event_file_link(struct trace_probe *tp, struct trace_event_file *file)
337{
338 struct event_file_link *link;
339
340 list_for_each_entry(link, &tp->files, list)
341 if (link->file == file)
342 return link;
343
344 return NULL;
345}
346
347extern int traceprobe_parse_probe_arg(char *arg, ssize_t *size,
348 struct probe_arg *parg, bool is_return, bool is_kprobe,
349 const struct fetch_type *ftbl);
350
351extern int traceprobe_conflict_field_name(const char *name,
352 struct probe_arg *args, int narg);
353
354extern void traceprobe_update_arg(struct probe_arg *arg);
355extern void traceprobe_free_probe_arg(struct probe_arg *arg);
356
357extern int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset);
358
359extern ssize_t traceprobe_probes_write(struct file *file,
360 const char __user *buffer, size_t count, loff_t *ppos,
361 int (*createfn)(int, char**));
362
363extern int traceprobe_command(const char *buf, int (*createfn)(int, char**));
364
365/* Sum up total data length for dynamic arraies (strings) */
366static nokprobe_inline int
367__get_data_size(struct trace_probe *tp, struct pt_regs *regs)
368{
369 int i, ret = 0;
370 u32 len;
371
372 for (i = 0; i < tp->nr_args; i++)
373 if (unlikely(tp->args[i].fetch_size.fn)) {
374 call_fetch(&tp->args[i].fetch_size, regs, &len);
375 ret += len;
376 }
377
378 return ret;
379}
380
381/* Store the value of each argument */
382static nokprobe_inline void
383store_trace_args(int ent_size, struct trace_probe *tp, struct pt_regs *regs,
384 u8 *data, int maxlen)
385{
386 int i;
387 u32 end = tp->size;
388 u32 *dl; /* Data (relative) location */
389
390 for (i = 0; i < tp->nr_args; i++) {
391 if (unlikely(tp->args[i].fetch_size.fn)) {
392 /*
393 * First, we set the relative location and
394 * maximum data length to *dl
395 */
396 dl = (u32 *)(data + tp->args[i].offset);
397 *dl = make_data_rloc(maxlen, end - tp->args[i].offset);
398 /* Then try to fetch string or dynamic array data */
399 call_fetch(&tp->args[i].fetch, regs, dl);
400 /* Reduce maximum length */
401 end += get_rloc_len(*dl);
402 maxlen -= get_rloc_len(*dl);
403 /* Trick here, convert data_rloc to data_loc */
404 *dl = convert_rloc_to_loc(*dl,
405 ent_size + tp->args[i].offset);
406 } else
407 /* Just fetching data normally */
408 call_fetch(&tp->args[i].fetch, regs,
409 data + tp->args[i].offset);
410 }
411}
412
413extern int set_print_fmt(struct trace_probe *tp, bool is_return);