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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/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_STRING_SIZE PATH_MAX
46
47/* Reserved field names */
48#define FIELD_STRING_IP "__probe_ip"
49#define FIELD_STRING_RETIP "__probe_ret_ip"
50#define FIELD_STRING_FUNC "__probe_func"
51
52#undef DEFINE_FIELD
53#define DEFINE_FIELD(type, item, name, is_signed) \
54 do { \
55 ret = trace_define_field(event_call, #type, name, \
56 offsetof(typeof(field), item), \
57 sizeof(field.item), is_signed, \
58 FILTER_OTHER); \
59 if (ret) \
60 return ret; \
61 } while (0)
62
63
64/* Flags for trace_probe */
65#define TP_FLAG_TRACE 1
66#define TP_FLAG_PROFILE 2
67#define TP_FLAG_REGISTERED 4
68
69
70/* data_rloc: data relative location, compatible with u32 */
71#define make_data_rloc(len, roffs) \
72 (((u32)(len) << 16) | ((u32)(roffs) & 0xffff))
73#define get_rloc_len(dl) ((u32)(dl) >> 16)
74#define get_rloc_offs(dl) ((u32)(dl) & 0xffff)
75
76/*
77 * Convert data_rloc to data_loc:
78 * data_rloc stores the offset from data_rloc itself, but data_loc
79 * stores the offset from event entry.
80 */
81#define convert_rloc_to_loc(dl, offs) ((u32)(dl) + (offs))
82
83static nokprobe_inline void *get_rloc_data(u32 *dl)
84{
85 return (u8 *)dl + get_rloc_offs(*dl);
86}
87
88/* For data_loc conversion */
89static nokprobe_inline void *get_loc_data(u32 *dl, void *ent)
90{
91 return (u8 *)ent + get_rloc_offs(*dl);
92}
93
94/* Data fetch function type */
95typedef void (*fetch_func_t)(struct pt_regs *, void *, void *);
96/* Printing function type */
97typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *, void *);
98
99/* Fetch types */
100enum {
101 FETCH_MTD_reg = 0,
102 FETCH_MTD_stack,
103 FETCH_MTD_retval,
104 FETCH_MTD_comm,
105 FETCH_MTD_memory,
106 FETCH_MTD_symbol,
107 FETCH_MTD_deref,
108 FETCH_MTD_bitfield,
109 FETCH_MTD_file_offset,
110 FETCH_MTD_END,
111};
112
113/* Fetch type information table */
114struct fetch_type {
115 const char *name; /* Name of type */
116 size_t size; /* Byte size of type */
117 int is_signed; /* Signed flag */
118 print_type_func_t print; /* Print functions */
119 const char *fmt; /* Fromat string */
120 const char *fmttype; /* Name in format file */
121 /* Fetch functions */
122 fetch_func_t fetch[FETCH_MTD_END];
123};
124
125struct fetch_param {
126 fetch_func_t fn;
127 void *data;
128};
129
130/* For defining macros, define string/string_size types */
131typedef u32 string;
132typedef u32 string_size;
133
134#define PRINT_TYPE_FUNC_NAME(type) print_type_##type
135#define PRINT_TYPE_FMT_NAME(type) print_type_format_##type
136
137/* Printing in basic type function template */
138#define DECLARE_BASIC_PRINT_TYPE_FUNC(type) \
139int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, const char *name, \
140 void *data, void *ent); \
141extern const char PRINT_TYPE_FMT_NAME(type)[]
142
143DECLARE_BASIC_PRINT_TYPE_FUNC(u8);
144DECLARE_BASIC_PRINT_TYPE_FUNC(u16);
145DECLARE_BASIC_PRINT_TYPE_FUNC(u32);
146DECLARE_BASIC_PRINT_TYPE_FUNC(u64);
147DECLARE_BASIC_PRINT_TYPE_FUNC(s8);
148DECLARE_BASIC_PRINT_TYPE_FUNC(s16);
149DECLARE_BASIC_PRINT_TYPE_FUNC(s32);
150DECLARE_BASIC_PRINT_TYPE_FUNC(s64);
151DECLARE_BASIC_PRINT_TYPE_FUNC(x8);
152DECLARE_BASIC_PRINT_TYPE_FUNC(x16);
153DECLARE_BASIC_PRINT_TYPE_FUNC(x32);
154DECLARE_BASIC_PRINT_TYPE_FUNC(x64);
155
156DECLARE_BASIC_PRINT_TYPE_FUNC(string);
157
158#define FETCH_FUNC_NAME(method, type) fetch_##method##_##type
159
160/* Declare macro for basic types */
161#define DECLARE_FETCH_FUNC(method, type) \
162extern void FETCH_FUNC_NAME(method, type)(struct pt_regs *regs, \
163 void *data, void *dest)
164
165#define DECLARE_BASIC_FETCH_FUNCS(method) \
166DECLARE_FETCH_FUNC(method, u8); \
167DECLARE_FETCH_FUNC(method, u16); \
168DECLARE_FETCH_FUNC(method, u32); \
169DECLARE_FETCH_FUNC(method, u64)
170
171DECLARE_BASIC_FETCH_FUNCS(reg);
172#define fetch_reg_string NULL
173#define fetch_reg_string_size NULL
174
175DECLARE_BASIC_FETCH_FUNCS(retval);
176#define fetch_retval_string NULL
177#define fetch_retval_string_size NULL
178
179DECLARE_BASIC_FETCH_FUNCS(symbol);
180DECLARE_FETCH_FUNC(symbol, string);
181DECLARE_FETCH_FUNC(symbol, string_size);
182
183DECLARE_BASIC_FETCH_FUNCS(deref);
184DECLARE_FETCH_FUNC(deref, string);
185DECLARE_FETCH_FUNC(deref, string_size);
186
187DECLARE_BASIC_FETCH_FUNCS(bitfield);
188#define fetch_bitfield_string NULL
189#define fetch_bitfield_string_size NULL
190
191/* comm only makes sense as a string */
192#define fetch_comm_u8 NULL
193#define fetch_comm_u16 NULL
194#define fetch_comm_u32 NULL
195#define fetch_comm_u64 NULL
196DECLARE_FETCH_FUNC(comm, string);
197DECLARE_FETCH_FUNC(comm, string_size);
198
199/*
200 * Define macro for basic types - we don't need to define s* types, because
201 * we have to care only about bitwidth at recording time.
202 */
203#define DEFINE_BASIC_FETCH_FUNCS(method) \
204DEFINE_FETCH_##method(u8) \
205DEFINE_FETCH_##method(u16) \
206DEFINE_FETCH_##method(u32) \
207DEFINE_FETCH_##method(u64)
208
209/* Default (unsigned long) fetch type */
210#define __DEFAULT_FETCH_TYPE(t) x##t
211#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)
212#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG)
213#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE)
214
215#define ASSIGN_FETCH_FUNC(method, type) \
216 [FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type)
217
218#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \
219 {.name = _name, \
220 .size = _size, \
221 .is_signed = sign, \
222 .print = PRINT_TYPE_FUNC_NAME(ptype), \
223 .fmt = PRINT_TYPE_FMT_NAME(ptype), \
224 .fmttype = _fmttype, \
225 .fetch = { \
226ASSIGN_FETCH_FUNC(reg, ftype), \
227ASSIGN_FETCH_FUNC(stack, ftype), \
228ASSIGN_FETCH_FUNC(retval, ftype), \
229ASSIGN_FETCH_FUNC(comm, ftype), \
230ASSIGN_FETCH_FUNC(memory, ftype), \
231ASSIGN_FETCH_FUNC(symbol, ftype), \
232ASSIGN_FETCH_FUNC(deref, ftype), \
233ASSIGN_FETCH_FUNC(bitfield, ftype), \
234ASSIGN_FETCH_FUNC(file_offset, ftype), \
235 } \
236 }
237
238#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \
239 __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype)
240
241/* If ptype is an alias of atype, use this macro (show atype in format) */
242#define ASSIGN_FETCH_TYPE_ALIAS(ptype, atype, ftype, sign) \
243 __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #atype)
244
245#define ASSIGN_FETCH_TYPE_END {}
246
247#define FETCH_TYPE_STRING 0
248#define FETCH_TYPE_STRSIZE 1
249
250#ifdef CONFIG_KPROBE_EVENTS
251struct symbol_cache;
252unsigned long update_symbol_cache(struct symbol_cache *sc);
253void free_symbol_cache(struct symbol_cache *sc);
254struct symbol_cache *alloc_symbol_cache(const char *sym, long offset);
255bool trace_kprobe_on_func_entry(struct trace_event_call *call);
256bool trace_kprobe_error_injectable(struct trace_event_call *call);
257#else
258/* uprobes do not support symbol fetch methods */
259#define fetch_symbol_u8 NULL
260#define fetch_symbol_u16 NULL
261#define fetch_symbol_u32 NULL
262#define fetch_symbol_u64 NULL
263#define fetch_symbol_string NULL
264#define fetch_symbol_string_size NULL
265
266struct symbol_cache {
267};
268static inline unsigned long __used update_symbol_cache(struct symbol_cache *sc)
269{
270 return 0;
271}
272
273static inline void __used free_symbol_cache(struct symbol_cache *sc)
274{
275}
276
277static inline struct symbol_cache * __used
278alloc_symbol_cache(const char *sym, long offset)
279{
280 return NULL;
281}
282
283static inline bool trace_kprobe_on_func_entry(struct trace_event_call *call)
284{
285 return false;
286}
287
288static inline bool trace_kprobe_error_injectable(struct trace_event_call *call)
289{
290 return false;
291}
292#endif /* CONFIG_KPROBE_EVENTS */
293
294struct probe_arg {
295 struct fetch_param fetch;
296 struct fetch_param fetch_size;
297 unsigned int offset; /* Offset from argument entry */
298 const char *name; /* Name of this argument */
299 const char *comm; /* Command of this argument */
300 const struct fetch_type *type; /* Type of this argument */
301};
302
303struct trace_probe {
304 unsigned int flags; /* For TP_FLAG_* */
305 struct trace_event_class class;
306 struct trace_event_call call;
307 struct list_head files;
308 ssize_t size; /* trace entry size */
309 unsigned int nr_args;
310 struct probe_arg args[];
311};
312
313struct event_file_link {
314 struct trace_event_file *file;
315 struct list_head list;
316};
317
318static inline bool trace_probe_is_enabled(struct trace_probe *tp)
319{
320 return !!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE));
321}
322
323static inline bool trace_probe_is_registered(struct trace_probe *tp)
324{
325 return !!(tp->flags & TP_FLAG_REGISTERED);
326}
327
328static nokprobe_inline void call_fetch(struct fetch_param *fprm,
329 struct pt_regs *regs, void *dest)
330{
331 return fprm->fn(regs, fprm->data, dest);
332}
333
334/* Check the name is good for event/group/fields */
335static inline bool is_good_name(const char *name)
336{
337 if (!isalpha(*name) && *name != '_')
338 return false;
339 while (*++name != '\0') {
340 if (!isalpha(*name) && !isdigit(*name) && *name != '_')
341 return false;
342 }
343 return true;
344}
345
346static inline struct event_file_link *
347find_event_file_link(struct trace_probe *tp, struct trace_event_file *file)
348{
349 struct event_file_link *link;
350
351 list_for_each_entry(link, &tp->files, list)
352 if (link->file == file)
353 return link;
354
355 return NULL;
356}
357
358extern int traceprobe_parse_probe_arg(char *arg, ssize_t *size,
359 struct probe_arg *parg, bool is_return, bool is_kprobe,
360 const struct fetch_type *ftbl);
361
362extern int traceprobe_conflict_field_name(const char *name,
363 struct probe_arg *args, int narg);
364
365extern void traceprobe_update_arg(struct probe_arg *arg);
366extern void traceprobe_free_probe_arg(struct probe_arg *arg);
367
368extern int traceprobe_split_symbol_offset(char *symbol, long *offset);
369
370/* Sum up total data length for dynamic arraies (strings) */
371static nokprobe_inline int
372__get_data_size(struct trace_probe *tp, struct pt_regs *regs)
373{
374 int i, ret = 0;
375 u32 len;
376
377 for (i = 0; i < tp->nr_args; i++)
378 if (unlikely(tp->args[i].fetch_size.fn)) {
379 call_fetch(&tp->args[i].fetch_size, regs, &len);
380 ret += len;
381 }
382
383 return ret;
384}
385
386/* Store the value of each argument */
387static nokprobe_inline void
388store_trace_args(int ent_size, struct trace_probe *tp, struct pt_regs *regs,
389 u8 *data, int maxlen)
390{
391 int i;
392 u32 end = tp->size;
393 u32 *dl; /* Data (relative) location */
394
395 for (i = 0; i < tp->nr_args; i++) {
396 if (unlikely(tp->args[i].fetch_size.fn)) {
397 /*
398 * First, we set the relative location and
399 * maximum data length to *dl
400 */
401 dl = (u32 *)(data + tp->args[i].offset);
402 *dl = make_data_rloc(maxlen, end - tp->args[i].offset);
403 /* Then try to fetch string or dynamic array data */
404 call_fetch(&tp->args[i].fetch, regs, dl);
405 /* Reduce maximum length */
406 end += get_rloc_len(*dl);
407 maxlen -= get_rloc_len(*dl);
408 /* Trick here, convert data_rloc to data_loc */
409 *dl = convert_rloc_to_loc(*dl,
410 ent_size + tp->args[i].offset);
411 } else
412 /* Just fetching data normally */
413 call_fetch(&tp->args[i].fetch, regs,
414 data + tp->args[i].offset);
415 }
416}
417
418extern int set_print_fmt(struct trace_probe *tp, bool is_return);
419
420#ifdef CONFIG_PERF_EVENTS
421extern struct trace_event_call *
422create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
423 bool is_return);
424extern void destroy_local_trace_kprobe(struct trace_event_call *event_call);
425
426extern struct trace_event_call *
427create_local_trace_uprobe(char *name, unsigned long offs, bool is_return);
428extern void destroy_local_trace_uprobe(struct trace_event_call *event_call);
429#endif
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**));