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13#include <linux/seq_file.h>
14#include <linux/slab.h>
15#include <linux/smp.h>
16#include <linux/tracefs.h>
17#include <linux/types.h>
18#include <linux/string.h>
19#include <linux/ctype.h>
20#include <linux/ptrace.h>
21#include <linux/perf_event.h>
22#include <linux/kprobes.h>
23#include <linux/stringify.h>
24#include <linux/limits.h>
25#include <linux/uaccess.h>
26#include <linux/bitops.h>
27#include <asm/bitsperlong.h>
28
29#include "trace.h"
30#include "trace_output.h"
31
32#define MAX_TRACE_ARGS 128
33#define MAX_ARGSTR_LEN 63
34#define MAX_ARRAY_LEN 64
35#define MAX_ARG_NAME_LEN 32
36#define MAX_STRING_SIZE PATH_MAX
37
38
39#define FIELD_STRING_IP "__probe_ip"
40#define FIELD_STRING_RETIP "__probe_ret_ip"
41#define FIELD_STRING_FUNC "__probe_func"
42
43#undef DEFINE_FIELD
44#define DEFINE_FIELD(type, item, name, is_signed) \
45 do { \
46 ret = trace_define_field(event_call, #type, name, \
47 offsetof(typeof(field), item), \
48 sizeof(field.item), is_signed, \
49 FILTER_OTHER); \
50 if (ret) \
51 return ret; \
52 } while (0)
53
54
55
56#define TP_FLAG_TRACE 1
57#define TP_FLAG_PROFILE 2
58
59
60#define make_data_loc(len, offs) \
61 (((u32)(len) << 16) | ((u32)(offs) & 0xffff))
62#define get_loc_len(dl) ((u32)(dl) >> 16)
63#define get_loc_offs(dl) ((u32)(dl) & 0xffff)
64
65static nokprobe_inline void *get_loc_data(u32 *dl, void *ent)
66{
67 return (u8 *)ent + get_loc_offs(*dl);
68}
69
70static nokprobe_inline u32 update_data_loc(u32 loc, int consumed)
71{
72 u32 maxlen = get_loc_len(loc);
73 u32 offset = get_loc_offs(loc);
74
75 return make_data_loc(maxlen - consumed, offset + consumed);
76}
77
78
79typedef int (*print_type_func_t)(struct trace_seq *, void *, void *);
80
81enum fetch_op {
82 FETCH_OP_NOP = 0,
83
84 FETCH_OP_REG,
85 FETCH_OP_STACK,
86 FETCH_OP_STACKP,
87 FETCH_OP_RETVAL,
88 FETCH_OP_IMM,
89 FETCH_OP_COMM,
90 FETCH_OP_ARG,
91 FETCH_OP_FOFFS,
92
93 FETCH_OP_DEREF,
94 FETCH_OP_UDEREF,
95
96 FETCH_OP_ST_RAW,
97 FETCH_OP_ST_MEM,
98 FETCH_OP_ST_UMEM,
99 FETCH_OP_ST_STRING,
100 FETCH_OP_ST_USTRING,
101
102 FETCH_OP_MOD_BF,
103
104 FETCH_OP_LP_ARRAY,
105 FETCH_OP_END,
106 FETCH_NOP_SYMBOL,
107};
108
109struct fetch_insn {
110 enum fetch_op op;
111 union {
112 unsigned int param;
113 struct {
114 unsigned int size;
115 int offset;
116 };
117 struct {
118 unsigned char basesize;
119 unsigned char lshift;
120 unsigned char rshift;
121 };
122 unsigned long immediate;
123 void *data;
124 };
125};
126
127
128#define FETCH_INSN_MAX 16
129#define FETCH_TOKEN_COMM (-ECOMM)
130
131
132struct fetch_type {
133 const char *name;
134 size_t size;
135 int is_signed;
136 print_type_func_t print;
137 const char *fmt;
138 const char *fmttype;
139};
140
141
142typedef u32 string;
143typedef u32 string_size;
144
145#define PRINT_TYPE_FUNC_NAME(type) print_type_##type
146#define PRINT_TYPE_FMT_NAME(type) print_type_format_##type
147
148
149#define DECLARE_BASIC_PRINT_TYPE_FUNC(type) \
150int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, void *data, void *ent);\
151extern const char PRINT_TYPE_FMT_NAME(type)[]
152
153DECLARE_BASIC_PRINT_TYPE_FUNC(u8);
154DECLARE_BASIC_PRINT_TYPE_FUNC(u16);
155DECLARE_BASIC_PRINT_TYPE_FUNC(u32);
156DECLARE_BASIC_PRINT_TYPE_FUNC(u64);
157DECLARE_BASIC_PRINT_TYPE_FUNC(s8);
158DECLARE_BASIC_PRINT_TYPE_FUNC(s16);
159DECLARE_BASIC_PRINT_TYPE_FUNC(s32);
160DECLARE_BASIC_PRINT_TYPE_FUNC(s64);
161DECLARE_BASIC_PRINT_TYPE_FUNC(x8);
162DECLARE_BASIC_PRINT_TYPE_FUNC(x16);
163DECLARE_BASIC_PRINT_TYPE_FUNC(x32);
164DECLARE_BASIC_PRINT_TYPE_FUNC(x64);
165
166DECLARE_BASIC_PRINT_TYPE_FUNC(string);
167DECLARE_BASIC_PRINT_TYPE_FUNC(symbol);
168
169
170#define __DEFAULT_FETCH_TYPE(t) x##t
171#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)
172#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG)
173#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE)
174
175#define __ADDR_FETCH_TYPE(t) u##t
176#define _ADDR_FETCH_TYPE(t) __ADDR_FETCH_TYPE(t)
177#define ADDR_FETCH_TYPE _ADDR_FETCH_TYPE(BITS_PER_LONG)
178
179#define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \
180 {.name = _name, \
181 .size = _size, \
182 .is_signed = sign, \
183 .print = PRINT_TYPE_FUNC_NAME(ptype), \
184 .fmt = PRINT_TYPE_FMT_NAME(ptype), \
185 .fmttype = _fmttype, \
186 }
187#define _ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \
188 __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, #_fmttype)
189#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \
190 _ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, ptype)
191
192
193#define ASSIGN_FETCH_TYPE_ALIAS(ptype, atype, ftype, sign) \
194 _ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, atype)
195
196#define ASSIGN_FETCH_TYPE_END {}
197#define MAX_ARRAY_LEN 64
198
199#ifdef CONFIG_KPROBE_EVENTS
200bool trace_kprobe_on_func_entry(struct trace_event_call *call);
201bool trace_kprobe_error_injectable(struct trace_event_call *call);
202#else
203static inline bool trace_kprobe_on_func_entry(struct trace_event_call *call)
204{
205 return false;
206}
207
208static inline bool trace_kprobe_error_injectable(struct trace_event_call *call)
209{
210 return false;
211}
212#endif
213
214struct probe_arg {
215 struct fetch_insn *code;
216 bool dynamic;
217 unsigned int offset;
218 unsigned int count;
219 const char *name;
220 const char *comm;
221 char *fmt;
222 const struct fetch_type *type;
223};
224
225struct trace_probe {
226 unsigned int flags;
227 struct trace_event_class class;
228 struct trace_event_call call;
229 struct list_head files;
230 ssize_t size;
231 unsigned int nr_args;
232 struct probe_arg args[];
233};
234
235struct event_file_link {
236 struct trace_event_file *file;
237 struct list_head list;
238};
239
240static inline bool trace_probe_test_flag(struct trace_probe *tp,
241 unsigned int flag)
242{
243 return !!(tp->flags & flag);
244}
245
246static inline void trace_probe_set_flag(struct trace_probe *tp,
247 unsigned int flag)
248{
249 tp->flags |= flag;
250}
251
252static inline void trace_probe_clear_flag(struct trace_probe *tp,
253 unsigned int flag)
254{
255 tp->flags &= ~flag;
256}
257
258static inline bool trace_probe_is_enabled(struct trace_probe *tp)
259{
260 return trace_probe_test_flag(tp, TP_FLAG_TRACE | TP_FLAG_PROFILE);
261}
262
263static inline const char *trace_probe_name(struct trace_probe *tp)
264{
265 return trace_event_name(&tp->call);
266}
267
268static inline const char *trace_probe_group_name(struct trace_probe *tp)
269{
270 return tp->call.class->system;
271}
272
273static inline struct trace_event_call *
274 trace_probe_event_call(struct trace_probe *tp)
275{
276 return &tp->call;
277}
278
279static inline int trace_probe_unregister_event_call(struct trace_probe *tp)
280{
281
282 return trace_remove_event_call(&tp->call);
283}
284
285static inline bool trace_probe_has_single_file(struct trace_probe *tp)
286{
287 return !!list_is_singular(&tp->files);
288}
289
290int trace_probe_init(struct trace_probe *tp, const char *event,
291 const char *group);
292void trace_probe_cleanup(struct trace_probe *tp);
293int trace_probe_register_event_call(struct trace_probe *tp);
294int trace_probe_add_file(struct trace_probe *tp, struct trace_event_file *file);
295int trace_probe_remove_file(struct trace_probe *tp,
296 struct trace_event_file *file);
297struct event_file_link *trace_probe_get_file_link(struct trace_probe *tp,
298 struct trace_event_file *file);
299
300#define trace_probe_for_each_link(pos, tp) \
301 list_for_each_entry(pos, &(tp)->files, list)
302#define trace_probe_for_each_link_rcu(pos, tp) \
303 list_for_each_entry_rcu(pos, &(tp)->files, list)
304
305
306static inline bool is_good_name(const char *name)
307{
308 if (!isalpha(*name) && *name != '_')
309 return false;
310 while (*++name != '\0') {
311 if (!isalpha(*name) && !isdigit(*name) && *name != '_')
312 return false;
313 }
314 return true;
315}
316
317#define TPARG_FL_RETURN BIT(0)
318#define TPARG_FL_KERNEL BIT(1)
319#define TPARG_FL_FENTRY BIT(2)
320#define TPARG_FL_MASK GENMASK(2, 0)
321
322extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i,
323 char *arg, unsigned int flags);
324
325extern int traceprobe_update_arg(struct probe_arg *arg);
326extern void traceprobe_free_probe_arg(struct probe_arg *arg);
327
328extern int traceprobe_split_symbol_offset(char *symbol, long *offset);
329int traceprobe_parse_event_name(const char **pevent, const char **pgroup,
330 char *buf, int offset);
331
332extern int traceprobe_set_print_fmt(struct trace_probe *tp, bool is_return);
333
334#ifdef CONFIG_PERF_EVENTS
335extern struct trace_event_call *
336create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
337 bool is_return);
338extern void destroy_local_trace_kprobe(struct trace_event_call *event_call);
339
340extern struct trace_event_call *
341create_local_trace_uprobe(char *name, unsigned long offs,
342 unsigned long ref_ctr_offset, bool is_return);
343extern void destroy_local_trace_uprobe(struct trace_event_call *event_call);
344#endif
345extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
346 size_t offset, struct trace_probe *tp);
347
348#undef ERRORS
349#define ERRORS \
350 C(FILE_NOT_FOUND, "Failed to find the given file"), \
351 C(NO_REGULAR_FILE, "Not a regular file"), \
352 C(BAD_REFCNT, "Invalid reference counter offset"), \
353 C(REFCNT_OPEN_BRACE, "Reference counter brace is not closed"), \
354 C(BAD_REFCNT_SUFFIX, "Reference counter has wrong suffix"), \
355 C(BAD_UPROBE_OFFS, "Invalid uprobe offset"), \
356 C(MAXACT_NO_KPROBE, "Maxactive is not for kprobe"), \
357 C(BAD_MAXACT, "Invalid maxactive number"), \
358 C(MAXACT_TOO_BIG, "Maxactive is too big"), \
359 C(BAD_PROBE_ADDR, "Invalid probed address or symbol"), \
360 C(BAD_RETPROBE, "Retprobe address must be an function entry"), \
361 C(NO_GROUP_NAME, "Group name is not specified"), \
362 C(GROUP_TOO_LONG, "Group name is too long"), \
363 C(BAD_GROUP_NAME, "Group name must follow the same rules as C identifiers"), \
364 C(NO_EVENT_NAME, "Event name is not specified"), \
365 C(EVENT_TOO_LONG, "Event name is too long"), \
366 C(BAD_EVENT_NAME, "Event name must follow the same rules as C identifiers"), \
367 C(RETVAL_ON_PROBE, "$retval is not available on probe"), \
368 C(BAD_STACK_NUM, "Invalid stack number"), \
369 C(BAD_ARG_NUM, "Invalid argument number"), \
370 C(BAD_VAR, "Invalid $-valiable specified"), \
371 C(BAD_REG_NAME, "Invalid register name"), \
372 C(BAD_MEM_ADDR, "Invalid memory address"), \
373 C(FILE_ON_KPROBE, "File offset is not available with kprobe"), \
374 C(BAD_FILE_OFFS, "Invalid file offset value"), \
375 C(SYM_ON_UPROBE, "Symbol is not available with uprobe"), \
376 C(TOO_MANY_OPS, "Dereference is too much nested"), \
377 C(DEREF_NEED_BRACE, "Dereference needs a brace"), \
378 C(BAD_DEREF_OFFS, "Invalid dereference offset"), \
379 C(DEREF_OPEN_BRACE, "Dereference brace is not closed"), \
380 C(COMM_CANT_DEREF, "$comm can not be dereferenced"), \
381 C(BAD_FETCH_ARG, "Invalid fetch argument"), \
382 C(ARRAY_NO_CLOSE, "Array is not closed"), \
383 C(BAD_ARRAY_SUFFIX, "Array has wrong suffix"), \
384 C(BAD_ARRAY_NUM, "Invalid array size"), \
385 C(ARRAY_TOO_BIG, "Array number is too big"), \
386 C(BAD_TYPE, "Unknown type is specified"), \
387 C(BAD_STRING, "String accepts only memory argument"), \
388 C(BAD_BITFIELD, "Invalid bitfield"), \
389 C(ARG_NAME_TOO_LONG, "Argument name is too long"), \
390 C(NO_ARG_NAME, "Argument name is not specified"), \
391 C(BAD_ARG_NAME, "Argument name must follow the same rules as C identifiers"), \
392 C(USED_ARG_NAME, "This argument name is already used"), \
393 C(ARG_TOO_LONG, "Argument expression is too long"), \
394 C(NO_ARG_BODY, "No argument expression"), \
395 C(BAD_INSN_BNDRY, "Probe point is not an instruction boundary"),\
396 C(FAIL_REG_PROBE, "Failed to register probe event"),
397
398#undef C
399#define C(a, b) TP_ERR_##a
400
401
402enum { ERRORS };
403
404
405
406struct trace_probe_log {
407 const char *subsystem;
408 const char **argv;
409 int argc;
410 int index;
411};
412
413void trace_probe_log_init(const char *subsystem, int argc, const char **argv);
414void trace_probe_log_set_index(int index);
415void trace_probe_log_clear(void);
416void __trace_probe_log_err(int offset, int err);
417
418#define trace_probe_log_err(offs, err) \
419 __trace_probe_log_err(offs, TP_ERR_##err)
420
