Commit | Line | Data |
---|---|---|
413d37d1 | 1 | /* |
77b44d1b | 2 | * Kprobes-based tracing events |
413d37d1 MH |
3 | * |
4 | * Created by Masami Hiramatsu <mhiramat@redhat.com> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
16 | * along with this program; if not, write to the Free Software | |
17 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
18 | */ | |
19 | ||
20 | #include <linux/module.h> | |
21 | #include <linux/uaccess.h> | |
22 | #include <linux/kprobes.h> | |
23 | #include <linux/seq_file.h> | |
24 | #include <linux/slab.h> | |
25 | #include <linux/smp.h> | |
26 | #include <linux/debugfs.h> | |
27 | #include <linux/types.h> | |
28 | #include <linux/string.h> | |
29 | #include <linux/ctype.h> | |
30 | #include <linux/ptrace.h> | |
d7a4b414 | 31 | #include <linux/perf_event.h> |
93ccae7a | 32 | #include <linux/stringify.h> |
e09c8614 MH |
33 | #include <linux/limits.h> |
34 | #include <linux/uaccess.h> | |
93ccae7a | 35 | #include <asm/bitsperlong.h> |
413d37d1 MH |
36 | |
37 | #include "trace.h" | |
38 | #include "trace_output.h" | |
39 | ||
a82378d8 | 40 | #define MAX_TRACE_ARGS 128 |
413d37d1 | 41 | #define MAX_ARGSTR_LEN 63 |
4263565d | 42 | #define MAX_EVENT_NAME_LEN 64 |
e09c8614 | 43 | #define MAX_STRING_SIZE PATH_MAX |
f52487e9 | 44 | #define KPROBE_EVENT_SYSTEM "kprobes" |
413d37d1 | 45 | |
a703d946 | 46 | /* Reserved field names */ |
e93f4d85 | 47 | #define FIELD_STRING_IP "__probe_ip" |
e93f4d85 MH |
48 | #define FIELD_STRING_RETIP "__probe_ret_ip" |
49 | #define FIELD_STRING_FUNC "__probe_func" | |
a703d946 MH |
50 | |
51 | const char *reserved_field_names[] = { | |
52 | "common_type", | |
53 | "common_flags", | |
54 | "common_preempt_count", | |
55 | "common_pid", | |
56 | "common_tgid", | |
57 | "common_lock_depth", | |
58 | FIELD_STRING_IP, | |
a703d946 MH |
59 | FIELD_STRING_RETIP, |
60 | FIELD_STRING_FUNC, | |
61 | }; | |
62 | ||
93ccae7a | 63 | /* Printing function type */ |
e09c8614 MH |
64 | typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *, |
65 | void *); | |
93ccae7a MH |
66 | #define PRINT_TYPE_FUNC_NAME(type) print_type_##type |
67 | #define PRINT_TYPE_FMT_NAME(type) print_type_format_##type | |
68 | ||
69 | /* Printing in basic type function template */ | |
70 | #define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt, cast) \ | |
71 | static __kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, \ | |
e09c8614 MH |
72 | const char *name, \ |
73 | void *data, void *ent)\ | |
93ccae7a MH |
74 | { \ |
75 | return trace_seq_printf(s, " %s=" fmt, name, (cast)*(type *)data);\ | |
76 | } \ | |
77 | static const char PRINT_TYPE_FMT_NAME(type)[] = fmt; | |
78 | ||
79 | DEFINE_BASIC_PRINT_TYPE_FUNC(u8, "%x", unsigned int) | |
80 | DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "%x", unsigned int) | |
81 | DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "%lx", unsigned long) | |
82 | DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "%llx", unsigned long long) | |
83 | DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d", int) | |
84 | DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d", int) | |
85 | DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%ld", long) | |
86 | DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%lld", long long) | |
87 | ||
e09c8614 MH |
88 | /* data_rloc: data relative location, compatible with u32 */ |
89 | #define make_data_rloc(len, roffs) \ | |
90 | (((u32)(len) << 16) | ((u32)(roffs) & 0xffff)) | |
91 | #define get_rloc_len(dl) ((u32)(dl) >> 16) | |
92 | #define get_rloc_offs(dl) ((u32)(dl) & 0xffff) | |
93 | ||
94 | static inline void *get_rloc_data(u32 *dl) | |
95 | { | |
96 | return (u8 *)dl + get_rloc_offs(*dl); | |
97 | } | |
98 | ||
99 | /* For data_loc conversion */ | |
100 | static inline void *get_loc_data(u32 *dl, void *ent) | |
101 | { | |
102 | return (u8 *)ent + get_rloc_offs(*dl); | |
103 | } | |
104 | ||
105 | /* | |
106 | * Convert data_rloc to data_loc: | |
107 | * data_rloc stores the offset from data_rloc itself, but data_loc | |
108 | * stores the offset from event entry. | |
109 | */ | |
110 | #define convert_rloc_to_loc(dl, offs) ((u32)(dl) + (offs)) | |
111 | ||
112 | /* For defining macros, define string/string_size types */ | |
113 | typedef u32 string; | |
114 | typedef u32 string_size; | |
115 | ||
116 | /* Print type function for string type */ | |
117 | static __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, | |
118 | const char *name, | |
119 | void *data, void *ent) | |
120 | { | |
121 | int len = *(u32 *)data >> 16; | |
122 | ||
123 | if (!len) | |
124 | return trace_seq_printf(s, " %s=(fault)", name); | |
125 | else | |
126 | return trace_seq_printf(s, " %s=\"%s\"", name, | |
127 | (const char *)get_loc_data(data, ent)); | |
128 | } | |
129 | static const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\""; | |
130 | ||
93ccae7a MH |
131 | /* Data fetch function type */ |
132 | typedef void (*fetch_func_t)(struct pt_regs *, void *, void *); | |
133 | ||
134 | struct fetch_param { | |
135 | fetch_func_t fn; | |
413d37d1 MH |
136 | void *data; |
137 | }; | |
138 | ||
93ccae7a MH |
139 | static __kprobes void call_fetch(struct fetch_param *fprm, |
140 | struct pt_regs *regs, void *dest) | |
413d37d1 | 141 | { |
93ccae7a | 142 | return fprm->fn(regs, fprm->data, dest); |
413d37d1 MH |
143 | } |
144 | ||
e09c8614 | 145 | #define FETCH_FUNC_NAME(method, type) fetch_##method##_##type |
93ccae7a MH |
146 | /* |
147 | * Define macro for basic types - we don't need to define s* types, because | |
148 | * we have to care only about bitwidth at recording time. | |
149 | */ | |
e09c8614 MH |
150 | #define DEFINE_BASIC_FETCH_FUNCS(method) \ |
151 | DEFINE_FETCH_##method(u8) \ | |
152 | DEFINE_FETCH_##method(u16) \ | |
153 | DEFINE_FETCH_##method(u32) \ | |
154 | DEFINE_FETCH_##method(u64) | |
155 | ||
156 | #define CHECK_FETCH_FUNCS(method, fn) \ | |
157 | (((FETCH_FUNC_NAME(method, u8) == fn) || \ | |
158 | (FETCH_FUNC_NAME(method, u16) == fn) || \ | |
159 | (FETCH_FUNC_NAME(method, u32) == fn) || \ | |
160 | (FETCH_FUNC_NAME(method, u64) == fn) || \ | |
161 | (FETCH_FUNC_NAME(method, string) == fn) || \ | |
162 | (FETCH_FUNC_NAME(method, string_size) == fn)) \ | |
163 | && (fn != NULL)) | |
93ccae7a MH |
164 | |
165 | /* Data fetch function templates */ | |
166 | #define DEFINE_FETCH_reg(type) \ | |
167 | static __kprobes void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs, \ | |
e09c8614 | 168 | void *offset, void *dest) \ |
93ccae7a MH |
169 | { \ |
170 | *(type *)dest = (type)regs_get_register(regs, \ | |
171 | (unsigned int)((unsigned long)offset)); \ | |
413d37d1 | 172 | } |
93ccae7a | 173 | DEFINE_BASIC_FETCH_FUNCS(reg) |
e09c8614 MH |
174 | /* No string on the register */ |
175 | #define fetch_reg_string NULL | |
176 | #define fetch_reg_string_size NULL | |
93ccae7a MH |
177 | |
178 | #define DEFINE_FETCH_stack(type) \ | |
179 | static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\ | |
180 | void *offset, void *dest) \ | |
181 | { \ | |
182 | *(type *)dest = (type)regs_get_kernel_stack_nth(regs, \ | |
183 | (unsigned int)((unsigned long)offset)); \ | |
413d37d1 | 184 | } |
93ccae7a | 185 | DEFINE_BASIC_FETCH_FUNCS(stack) |
e09c8614 MH |
186 | /* No string on the stack entry */ |
187 | #define fetch_stack_string NULL | |
188 | #define fetch_stack_string_size NULL | |
413d37d1 | 189 | |
93ccae7a MH |
190 | #define DEFINE_FETCH_retval(type) \ |
191 | static __kprobes void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs,\ | |
192 | void *dummy, void *dest) \ | |
193 | { \ | |
194 | *(type *)dest = (type)regs_return_value(regs); \ | |
413d37d1 | 195 | } |
93ccae7a | 196 | DEFINE_BASIC_FETCH_FUNCS(retval) |
e09c8614 MH |
197 | /* No string on the retval */ |
198 | #define fetch_retval_string NULL | |
199 | #define fetch_retval_string_size NULL | |
93ccae7a MH |
200 | |
201 | #define DEFINE_FETCH_memory(type) \ | |
202 | static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\ | |
203 | void *addr, void *dest) \ | |
204 | { \ | |
205 | type retval; \ | |
206 | if (probe_kernel_address(addr, retval)) \ | |
207 | *(type *)dest = 0; \ | |
208 | else \ | |
209 | *(type *)dest = retval; \ | |
413d37d1 | 210 | } |
93ccae7a | 211 | DEFINE_BASIC_FETCH_FUNCS(memory) |
e09c8614 MH |
212 | /* |
213 | * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max | |
214 | * length and relative data location. | |
215 | */ | |
216 | static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, | |
217 | void *addr, void *dest) | |
218 | { | |
219 | long ret; | |
220 | int maxlen = get_rloc_len(*(u32 *)dest); | |
221 | u8 *dst = get_rloc_data(dest); | |
222 | u8 *src = addr; | |
223 | mm_segment_t old_fs = get_fs(); | |
224 | if (!maxlen) | |
225 | return; | |
226 | /* | |
227 | * Try to get string again, since the string can be changed while | |
228 | * probing. | |
229 | */ | |
230 | set_fs(KERNEL_DS); | |
231 | pagefault_disable(); | |
232 | do | |
233 | ret = __copy_from_user_inatomic(dst++, src++, 1); | |
234 | while (dst[-1] && ret == 0 && src - (u8 *)addr < maxlen); | |
235 | dst[-1] = '\0'; | |
236 | pagefault_enable(); | |
237 | set_fs(old_fs); | |
238 | ||
239 | if (ret < 0) { /* Failed to fetch string */ | |
240 | ((u8 *)get_rloc_data(dest))[0] = '\0'; | |
241 | *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest)); | |
242 | } else | |
243 | *(u32 *)dest = make_data_rloc(src - (u8 *)addr, | |
244 | get_rloc_offs(*(u32 *)dest)); | |
245 | } | |
246 | /* Return the length of string -- including null terminal byte */ | |
247 | static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs, | |
248 | void *addr, void *dest) | |
249 | { | |
250 | int ret, len = 0; | |
251 | u8 c; | |
252 | mm_segment_t old_fs = get_fs(); | |
253 | ||
254 | set_fs(KERNEL_DS); | |
255 | pagefault_disable(); | |
256 | do { | |
257 | ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1); | |
258 | len++; | |
259 | } while (c && ret == 0 && len < MAX_STRING_SIZE); | |
260 | pagefault_enable(); | |
261 | set_fs(old_fs); | |
262 | ||
263 | if (ret < 0) /* Failed to check the length */ | |
264 | *(u32 *)dest = 0; | |
265 | else | |
266 | *(u32 *)dest = len; | |
267 | } | |
413d37d1 MH |
268 | |
269 | /* Memory fetching by symbol */ | |
270 | struct symbol_cache { | |
271 | char *symbol; | |
272 | long offset; | |
273 | unsigned long addr; | |
274 | }; | |
275 | ||
276 | static unsigned long update_symbol_cache(struct symbol_cache *sc) | |
277 | { | |
278 | sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol); | |
279 | if (sc->addr) | |
280 | sc->addr += sc->offset; | |
281 | return sc->addr; | |
282 | } | |
283 | ||
284 | static void free_symbol_cache(struct symbol_cache *sc) | |
285 | { | |
286 | kfree(sc->symbol); | |
287 | kfree(sc); | |
288 | } | |
289 | ||
290 | static struct symbol_cache *alloc_symbol_cache(const char *sym, long offset) | |
291 | { | |
292 | struct symbol_cache *sc; | |
293 | ||
294 | if (!sym || strlen(sym) == 0) | |
295 | return NULL; | |
296 | sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL); | |
297 | if (!sc) | |
298 | return NULL; | |
299 | ||
300 | sc->symbol = kstrdup(sym, GFP_KERNEL); | |
301 | if (!sc->symbol) { | |
302 | kfree(sc); | |
303 | return NULL; | |
304 | } | |
305 | sc->offset = offset; | |
306 | ||
307 | update_symbol_cache(sc); | |
308 | return sc; | |
309 | } | |
310 | ||
93ccae7a MH |
311 | #define DEFINE_FETCH_symbol(type) \ |
312 | static __kprobes void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs,\ | |
313 | void *data, void *dest) \ | |
314 | { \ | |
315 | struct symbol_cache *sc = data; \ | |
316 | if (sc->addr) \ | |
317 | fetch_memory_##type(regs, (void *)sc->addr, dest); \ | |
318 | else \ | |
319 | *(type *)dest = 0; \ | |
413d37d1 | 320 | } |
93ccae7a | 321 | DEFINE_BASIC_FETCH_FUNCS(symbol) |
e09c8614 MH |
322 | DEFINE_FETCH_symbol(string) |
323 | DEFINE_FETCH_symbol(string_size) | |
413d37d1 | 324 | |
93ccae7a MH |
325 | /* Dereference memory access function */ |
326 | struct deref_fetch_param { | |
327 | struct fetch_param orig; | |
413d37d1 MH |
328 | long offset; |
329 | }; | |
330 | ||
93ccae7a MH |
331 | #define DEFINE_FETCH_deref(type) \ |
332 | static __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs,\ | |
333 | void *data, void *dest) \ | |
334 | { \ | |
335 | struct deref_fetch_param *dprm = data; \ | |
336 | unsigned long addr; \ | |
337 | call_fetch(&dprm->orig, regs, &addr); \ | |
338 | if (addr) { \ | |
339 | addr += dprm->offset; \ | |
340 | fetch_memory_##type(regs, (void *)addr, dest); \ | |
341 | } else \ | |
342 | *(type *)dest = 0; \ | |
413d37d1 | 343 | } |
93ccae7a | 344 | DEFINE_BASIC_FETCH_FUNCS(deref) |
e09c8614 MH |
345 | DEFINE_FETCH_deref(string) |
346 | DEFINE_FETCH_deref(string_size) | |
413d37d1 | 347 | |
93ccae7a | 348 | static __kprobes void free_deref_fetch_param(struct deref_fetch_param *data) |
413d37d1 | 349 | { |
e09c8614 | 350 | if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) |
93ccae7a | 351 | free_deref_fetch_param(data->orig.data); |
e09c8614 | 352 | else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) |
413d37d1 MH |
353 | free_symbol_cache(data->orig.data); |
354 | kfree(data); | |
355 | } | |
356 | ||
93ccae7a MH |
357 | /* Default (unsigned long) fetch type */ |
358 | #define __DEFAULT_FETCH_TYPE(t) u##t | |
359 | #define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t) | |
360 | #define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG) | |
361 | #define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE) | |
362 | ||
e09c8614 MH |
363 | /* Fetch types */ |
364 | enum { | |
365 | FETCH_MTD_reg = 0, | |
366 | FETCH_MTD_stack, | |
367 | FETCH_MTD_retval, | |
368 | FETCH_MTD_memory, | |
369 | FETCH_MTD_symbol, | |
370 | FETCH_MTD_deref, | |
371 | FETCH_MTD_END, | |
372 | }; | |
373 | ||
374 | #define ASSIGN_FETCH_FUNC(method, type) \ | |
375 | [FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type) | |
376 | ||
377 | #define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \ | |
378 | {.name = _name, \ | |
379 | .size = _size, \ | |
380 | .is_signed = sign, \ | |
381 | .print = PRINT_TYPE_FUNC_NAME(ptype), \ | |
382 | .fmt = PRINT_TYPE_FMT_NAME(ptype), \ | |
383 | .fmttype = _fmttype, \ | |
384 | .fetch = { \ | |
385 | ASSIGN_FETCH_FUNC(reg, ftype), \ | |
386 | ASSIGN_FETCH_FUNC(stack, ftype), \ | |
387 | ASSIGN_FETCH_FUNC(retval, ftype), \ | |
388 | ASSIGN_FETCH_FUNC(memory, ftype), \ | |
389 | ASSIGN_FETCH_FUNC(symbol, ftype), \ | |
390 | ASSIGN_FETCH_FUNC(deref, ftype), \ | |
391 | } \ | |
93ccae7a MH |
392 | } |
393 | ||
e09c8614 MH |
394 | #define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \ |
395 | __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype) | |
396 | ||
397 | #define FETCH_TYPE_STRING 0 | |
398 | #define FETCH_TYPE_STRSIZE 1 | |
399 | ||
93ccae7a MH |
400 | /* Fetch type information table */ |
401 | static const struct fetch_type { | |
402 | const char *name; /* Name of type */ | |
403 | size_t size; /* Byte size of type */ | |
404 | int is_signed; /* Signed flag */ | |
405 | print_type_func_t print; /* Print functions */ | |
406 | const char *fmt; /* Fromat string */ | |
e09c8614 | 407 | const char *fmttype; /* Name in format file */ |
93ccae7a | 408 | /* Fetch functions */ |
e09c8614 | 409 | fetch_func_t fetch[FETCH_MTD_END]; |
93ccae7a | 410 | } fetch_type_table[] = { |
e09c8614 MH |
411 | /* Special types */ |
412 | [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string, | |
413 | sizeof(u32), 1, "__data_loc char[]"), | |
414 | [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32, | |
415 | string_size, sizeof(u32), 0, "u32"), | |
416 | /* Basic types */ | |
93ccae7a MH |
417 | ASSIGN_FETCH_TYPE(u8, u8, 0), |
418 | ASSIGN_FETCH_TYPE(u16, u16, 0), | |
419 | ASSIGN_FETCH_TYPE(u32, u32, 0), | |
420 | ASSIGN_FETCH_TYPE(u64, u64, 0), | |
421 | ASSIGN_FETCH_TYPE(s8, u8, 1), | |
422 | ASSIGN_FETCH_TYPE(s16, u16, 1), | |
423 | ASSIGN_FETCH_TYPE(s32, u32, 1), | |
424 | ASSIGN_FETCH_TYPE(s64, u64, 1), | |
425 | }; | |
426 | ||
427 | static const struct fetch_type *find_fetch_type(const char *type) | |
428 | { | |
429 | int i; | |
430 | ||
431 | if (!type) | |
432 | type = DEFAULT_FETCH_TYPE_STR; | |
433 | ||
434 | for (i = 0; i < ARRAY_SIZE(fetch_type_table); i++) | |
435 | if (strcmp(type, fetch_type_table[i].name) == 0) | |
436 | return &fetch_type_table[i]; | |
437 | return NULL; | |
438 | } | |
439 | ||
440 | /* Special function : only accept unsigned long */ | |
441 | static __kprobes void fetch_stack_address(struct pt_regs *regs, | |
442 | void *dummy, void *dest) | |
443 | { | |
444 | *(unsigned long *)dest = kernel_stack_pointer(regs); | |
445 | } | |
446 | ||
e09c8614 MH |
447 | static fetch_func_t get_fetch_size_function(const struct fetch_type *type, |
448 | fetch_func_t orig_fn) | |
449 | { | |
450 | int i; | |
451 | ||
452 | if (type != &fetch_type_table[FETCH_TYPE_STRING]) | |
453 | return NULL; /* Only string type needs size function */ | |
454 | for (i = 0; i < FETCH_MTD_END; i++) | |
455 | if (type->fetch[i] == orig_fn) | |
456 | return fetch_type_table[FETCH_TYPE_STRSIZE].fetch[i]; | |
457 | ||
458 | WARN_ON(1); /* This should not happen */ | |
459 | return NULL; | |
460 | } | |
461 | ||
413d37d1 | 462 | /** |
77b44d1b | 463 | * Kprobe event core functions |
413d37d1 MH |
464 | */ |
465 | ||
eca0d916 | 466 | struct probe_arg { |
93ccae7a | 467 | struct fetch_param fetch; |
e09c8614 | 468 | struct fetch_param fetch_size; |
93ccae7a MH |
469 | unsigned int offset; /* Offset from argument entry */ |
470 | const char *name; /* Name of this argument */ | |
471 | const char *comm; /* Command of this argument */ | |
472 | const struct fetch_type *type; /* Type of this argument */ | |
eca0d916 MH |
473 | }; |
474 | ||
50d78056 MH |
475 | /* Flags for trace_probe */ |
476 | #define TP_FLAG_TRACE 1 | |
477 | #define TP_FLAG_PROFILE 2 | |
478 | ||
413d37d1 MH |
479 | struct trace_probe { |
480 | struct list_head list; | |
4a846b44 | 481 | struct kretprobe rp; /* Use rp.kp for kprobe use */ |
cd7e7bd5 | 482 | unsigned long nhit; |
50d78056 | 483 | unsigned int flags; /* For TP_FLAG_* */ |
413d37d1 | 484 | const char *symbol; /* symbol name */ |
2239291a | 485 | struct ftrace_event_class class; |
413d37d1 | 486 | struct ftrace_event_call call; |
93ccae7a | 487 | ssize_t size; /* trace entry size */ |
a82378d8 | 488 | unsigned int nr_args; |
eca0d916 | 489 | struct probe_arg args[]; |
413d37d1 MH |
490 | }; |
491 | ||
a82378d8 MH |
492 | #define SIZEOF_TRACE_PROBE(n) \ |
493 | (offsetof(struct trace_probe, args) + \ | |
eca0d916 | 494 | (sizeof(struct probe_arg) * (n))) |
a82378d8 | 495 | |
93ccae7a | 496 | |
413d37d1 MH |
497 | static __kprobes int probe_is_return(struct trace_probe *tp) |
498 | { | |
4a846b44 | 499 | return tp->rp.handler != NULL; |
413d37d1 MH |
500 | } |
501 | ||
502 | static __kprobes const char *probe_symbol(struct trace_probe *tp) | |
503 | { | |
504 | return tp->symbol ? tp->symbol : "unknown"; | |
505 | } | |
506 | ||
413d37d1 MH |
507 | static int register_probe_event(struct trace_probe *tp); |
508 | static void unregister_probe_event(struct trace_probe *tp); | |
509 | ||
510 | static DEFINE_MUTEX(probe_lock); | |
511 | static LIST_HEAD(probe_list); | |
512 | ||
50d78056 MH |
513 | static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs); |
514 | static int kretprobe_dispatcher(struct kretprobe_instance *ri, | |
515 | struct pt_regs *regs); | |
516 | ||
6f3cf440 MH |
517 | /* Check the name is good for event/group */ |
518 | static int check_event_name(const char *name) | |
519 | { | |
520 | if (!isalpha(*name) && *name != '_') | |
521 | return 0; | |
522 | while (*++name != '\0') { | |
523 | if (!isalpha(*name) && !isdigit(*name) && *name != '_') | |
524 | return 0; | |
525 | } | |
526 | return 1; | |
527 | } | |
528 | ||
4a846b44 MH |
529 | /* |
530 | * Allocate new trace_probe and initialize it (including kprobes). | |
531 | */ | |
f52487e9 MH |
532 | static struct trace_probe *alloc_trace_probe(const char *group, |
533 | const char *event, | |
4a846b44 MH |
534 | void *addr, |
535 | const char *symbol, | |
536 | unsigned long offs, | |
537 | int nargs, int is_return) | |
413d37d1 MH |
538 | { |
539 | struct trace_probe *tp; | |
6f3cf440 | 540 | int ret = -ENOMEM; |
413d37d1 | 541 | |
a82378d8 | 542 | tp = kzalloc(SIZEOF_TRACE_PROBE(nargs), GFP_KERNEL); |
413d37d1 | 543 | if (!tp) |
6f3cf440 | 544 | return ERR_PTR(ret); |
413d37d1 MH |
545 | |
546 | if (symbol) { | |
547 | tp->symbol = kstrdup(symbol, GFP_KERNEL); | |
548 | if (!tp->symbol) | |
549 | goto error; | |
4a846b44 MH |
550 | tp->rp.kp.symbol_name = tp->symbol; |
551 | tp->rp.kp.offset = offs; | |
552 | } else | |
553 | tp->rp.kp.addr = addr; | |
554 | ||
555 | if (is_return) | |
50d78056 | 556 | tp->rp.handler = kretprobe_dispatcher; |
4a846b44 | 557 | else |
50d78056 | 558 | tp->rp.kp.pre_handler = kprobe_dispatcher; |
4a846b44 | 559 | |
6f3cf440 MH |
560 | if (!event || !check_event_name(event)) { |
561 | ret = -EINVAL; | |
4263565d | 562 | goto error; |
6f3cf440 MH |
563 | } |
564 | ||
2239291a | 565 | tp->call.class = &tp->class; |
4263565d MH |
566 | tp->call.name = kstrdup(event, GFP_KERNEL); |
567 | if (!tp->call.name) | |
568 | goto error; | |
413d37d1 | 569 | |
6f3cf440 MH |
570 | if (!group || !check_event_name(group)) { |
571 | ret = -EINVAL; | |
f52487e9 | 572 | goto error; |
6f3cf440 MH |
573 | } |
574 | ||
2239291a SR |
575 | tp->class.system = kstrdup(group, GFP_KERNEL); |
576 | if (!tp->class.system) | |
f52487e9 MH |
577 | goto error; |
578 | ||
413d37d1 MH |
579 | INIT_LIST_HEAD(&tp->list); |
580 | return tp; | |
581 | error: | |
f52487e9 | 582 | kfree(tp->call.name); |
413d37d1 MH |
583 | kfree(tp->symbol); |
584 | kfree(tp); | |
6f3cf440 | 585 | return ERR_PTR(ret); |
413d37d1 MH |
586 | } |
587 | ||
eca0d916 MH |
588 | static void free_probe_arg(struct probe_arg *arg) |
589 | { | |
e09c8614 | 590 | if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn)) |
93ccae7a | 591 | free_deref_fetch_param(arg->fetch.data); |
e09c8614 | 592 | else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn)) |
eca0d916 | 593 | free_symbol_cache(arg->fetch.data); |
eca0d916 | 594 | kfree(arg->name); |
93ccae7a | 595 | kfree(arg->comm); |
eca0d916 MH |
596 | } |
597 | ||
413d37d1 MH |
598 | static void free_trace_probe(struct trace_probe *tp) |
599 | { | |
600 | int i; | |
601 | ||
602 | for (i = 0; i < tp->nr_args; i++) | |
eca0d916 | 603 | free_probe_arg(&tp->args[i]); |
413d37d1 | 604 | |
8f082018 | 605 | kfree(tp->call.class->system); |
413d37d1 MH |
606 | kfree(tp->call.name); |
607 | kfree(tp->symbol); | |
608 | kfree(tp); | |
609 | } | |
610 | ||
dd004c47 MH |
611 | static struct trace_probe *find_probe_event(const char *event, |
612 | const char *group) | |
413d37d1 MH |
613 | { |
614 | struct trace_probe *tp; | |
615 | ||
616 | list_for_each_entry(tp, &probe_list, list) | |
dd004c47 | 617 | if (strcmp(tp->call.name, event) == 0 && |
8f082018 | 618 | strcmp(tp->call.class->system, group) == 0) |
413d37d1 MH |
619 | return tp; |
620 | return NULL; | |
621 | } | |
622 | ||
2d5e067e MH |
623 | /* Unregister a trace_probe and probe_event: call with locking probe_lock */ |
624 | static void unregister_trace_probe(struct trace_probe *tp) | |
413d37d1 MH |
625 | { |
626 | if (probe_is_return(tp)) | |
627 | unregister_kretprobe(&tp->rp); | |
628 | else | |
4a846b44 | 629 | unregister_kprobe(&tp->rp.kp); |
413d37d1 | 630 | list_del(&tp->list); |
2d5e067e | 631 | unregister_probe_event(tp); |
413d37d1 MH |
632 | } |
633 | ||
634 | /* Register a trace_probe and probe_event */ | |
635 | static int register_trace_probe(struct trace_probe *tp) | |
636 | { | |
637 | struct trace_probe *old_tp; | |
638 | int ret; | |
639 | ||
640 | mutex_lock(&probe_lock); | |
641 | ||
2d5e067e | 642 | /* register as an event */ |
8f082018 | 643 | old_tp = find_probe_event(tp->call.name, tp->call.class->system); |
2d5e067e MH |
644 | if (old_tp) { |
645 | /* delete old event */ | |
646 | unregister_trace_probe(old_tp); | |
647 | free_trace_probe(old_tp); | |
648 | } | |
649 | ret = register_probe_event(tp); | |
650 | if (ret) { | |
651 | pr_warning("Faild to register probe event(%d)\n", ret); | |
652 | goto end; | |
653 | } | |
654 | ||
5a0d9050 | 655 | tp->rp.kp.flags |= KPROBE_FLAG_DISABLED; |
413d37d1 MH |
656 | if (probe_is_return(tp)) |
657 | ret = register_kretprobe(&tp->rp); | |
658 | else | |
4a846b44 | 659 | ret = register_kprobe(&tp->rp.kp); |
413d37d1 MH |
660 | |
661 | if (ret) { | |
662 | pr_warning("Could not insert probe(%d)\n", ret); | |
663 | if (ret == -EILSEQ) { | |
664 | pr_warning("Probing address(0x%p) is not an " | |
665 | "instruction boundary.\n", | |
4a846b44 | 666 | tp->rp.kp.addr); |
413d37d1 MH |
667 | ret = -EINVAL; |
668 | } | |
2d5e067e MH |
669 | unregister_probe_event(tp); |
670 | } else | |
671 | list_add_tail(&tp->list, &probe_list); | |
413d37d1 MH |
672 | end: |
673 | mutex_unlock(&probe_lock); | |
674 | return ret; | |
675 | } | |
676 | ||
677 | /* Split symbol and offset. */ | |
2fba0c88 | 678 | static int split_symbol_offset(char *symbol, unsigned long *offset) |
413d37d1 MH |
679 | { |
680 | char *tmp; | |
681 | int ret; | |
682 | ||
683 | if (!offset) | |
684 | return -EINVAL; | |
685 | ||
686 | tmp = strchr(symbol, '+'); | |
413d37d1 MH |
687 | if (tmp) { |
688 | /* skip sign because strict_strtol doesn't accept '+' */ | |
2fba0c88 | 689 | ret = strict_strtoul(tmp + 1, 0, offset); |
413d37d1 MH |
690 | if (ret) |
691 | return ret; | |
413d37d1 MH |
692 | *tmp = '\0'; |
693 | } else | |
694 | *offset = 0; | |
695 | return 0; | |
696 | } | |
697 | ||
698 | #define PARAM_MAX_ARGS 16 | |
699 | #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) | |
700 | ||
93ccae7a MH |
701 | static int parse_probe_vars(char *arg, const struct fetch_type *t, |
702 | struct fetch_param *f, int is_return) | |
413d37d1 MH |
703 | { |
704 | int ret = 0; | |
705 | unsigned long param; | |
413d37d1 | 706 | |
2e06ff63 | 707 | if (strcmp(arg, "retval") == 0) { |
93ccae7a | 708 | if (is_return) |
e09c8614 | 709 | f->fn = t->fetch[FETCH_MTD_retval]; |
93ccae7a | 710 | else |
413d37d1 | 711 | ret = -EINVAL; |
2e06ff63 MH |
712 | } else if (strncmp(arg, "stack", 5) == 0) { |
713 | if (arg[5] == '\0') { | |
93ccae7a MH |
714 | if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0) |
715 | f->fn = fetch_stack_address; | |
716 | else | |
717 | ret = -EINVAL; | |
2e06ff63 MH |
718 | } else if (isdigit(arg[5])) { |
719 | ret = strict_strtoul(arg + 5, 10, ¶m); | |
413d37d1 MH |
720 | if (ret || param > PARAM_MAX_STACK) |
721 | ret = -EINVAL; | |
722 | else { | |
e09c8614 | 723 | f->fn = t->fetch[FETCH_MTD_stack]; |
93ccae7a | 724 | f->data = (void *)param; |
413d37d1 | 725 | } |
2e06ff63 MH |
726 | } else |
727 | ret = -EINVAL; | |
2e06ff63 | 728 | } else |
405b2651 | 729 | ret = -EINVAL; |
405b2651 MH |
730 | return ret; |
731 | } | |
732 | ||
ba8665d7 | 733 | /* Recursive argument parser */ |
93ccae7a MH |
734 | static int __parse_probe_arg(char *arg, const struct fetch_type *t, |
735 | struct fetch_param *f, int is_return) | |
405b2651 MH |
736 | { |
737 | int ret = 0; | |
738 | unsigned long param; | |
739 | long offset; | |
740 | char *tmp; | |
741 | ||
742 | switch (arg[0]) { | |
743 | case '$': | |
93ccae7a | 744 | ret = parse_probe_vars(arg + 1, t, f, is_return); |
405b2651 MH |
745 | break; |
746 | case '%': /* named register */ | |
747 | ret = regs_query_register_offset(arg + 1); | |
748 | if (ret >= 0) { | |
e09c8614 | 749 | f->fn = t->fetch[FETCH_MTD_reg]; |
93ccae7a | 750 | f->data = (void *)(unsigned long)ret; |
405b2651 MH |
751 | ret = 0; |
752 | } | |
753 | break; | |
413d37d1 MH |
754 | case '@': /* memory or symbol */ |
755 | if (isdigit(arg[1])) { | |
756 | ret = strict_strtoul(arg + 1, 0, ¶m); | |
757 | if (ret) | |
758 | break; | |
e09c8614 | 759 | f->fn = t->fetch[FETCH_MTD_memory]; |
93ccae7a | 760 | f->data = (void *)param; |
413d37d1 MH |
761 | } else { |
762 | ret = split_symbol_offset(arg + 1, &offset); | |
763 | if (ret) | |
764 | break; | |
93ccae7a MH |
765 | f->data = alloc_symbol_cache(arg + 1, offset); |
766 | if (f->data) | |
e09c8614 | 767 | f->fn = t->fetch[FETCH_MTD_symbol]; |
413d37d1 MH |
768 | } |
769 | break; | |
93ccae7a | 770 | case '+': /* deref memory */ |
413d37d1 MH |
771 | case '-': |
772 | tmp = strchr(arg, '('); | |
93ccae7a | 773 | if (!tmp) |
413d37d1 | 774 | break; |
413d37d1 MH |
775 | *tmp = '\0'; |
776 | ret = strict_strtol(arg + 1, 0, &offset); | |
777 | if (ret) | |
778 | break; | |
779 | if (arg[0] == '-') | |
780 | offset = -offset; | |
781 | arg = tmp + 1; | |
782 | tmp = strrchr(arg, ')'); | |
783 | if (tmp) { | |
93ccae7a MH |
784 | struct deref_fetch_param *dprm; |
785 | const struct fetch_type *t2 = find_fetch_type(NULL); | |
413d37d1 | 786 | *tmp = '\0'; |
93ccae7a MH |
787 | dprm = kzalloc(sizeof(struct deref_fetch_param), |
788 | GFP_KERNEL); | |
789 | if (!dprm) | |
413d37d1 | 790 | return -ENOMEM; |
93ccae7a MH |
791 | dprm->offset = offset; |
792 | ret = __parse_probe_arg(arg, t2, &dprm->orig, | |
793 | is_return); | |
413d37d1 | 794 | if (ret) |
93ccae7a | 795 | kfree(dprm); |
413d37d1 | 796 | else { |
e09c8614 | 797 | f->fn = t->fetch[FETCH_MTD_deref]; |
93ccae7a | 798 | f->data = (void *)dprm; |
413d37d1 | 799 | } |
93ccae7a | 800 | } |
413d37d1 | 801 | break; |
413d37d1 | 802 | } |
e09c8614 MH |
803 | if (!ret && !f->fn) { /* Parsed, but do not find fetch method */ |
804 | pr_info("%s type has no corresponding fetch method.\n", | |
805 | t->name); | |
93ccae7a | 806 | ret = -EINVAL; |
e09c8614 | 807 | } |
413d37d1 MH |
808 | return ret; |
809 | } | |
810 | ||
ba8665d7 | 811 | /* String length checking wrapper */ |
93ccae7a MH |
812 | static int parse_probe_arg(char *arg, struct trace_probe *tp, |
813 | struct probe_arg *parg, int is_return) | |
ba8665d7 | 814 | { |
93ccae7a | 815 | const char *t; |
e09c8614 | 816 | int ret; |
93ccae7a | 817 | |
ba8665d7 MH |
818 | if (strlen(arg) > MAX_ARGSTR_LEN) { |
819 | pr_info("Argument is too long.: %s\n", arg); | |
820 | return -ENOSPC; | |
821 | } | |
93ccae7a MH |
822 | parg->comm = kstrdup(arg, GFP_KERNEL); |
823 | if (!parg->comm) { | |
824 | pr_info("Failed to allocate memory for command '%s'.\n", arg); | |
825 | return -ENOMEM; | |
826 | } | |
827 | t = strchr(parg->comm, ':'); | |
828 | if (t) { | |
829 | arg[t - parg->comm] = '\0'; | |
830 | t++; | |
831 | } | |
832 | parg->type = find_fetch_type(t); | |
833 | if (!parg->type) { | |
834 | pr_info("Unsupported type: %s\n", t); | |
835 | return -EINVAL; | |
836 | } | |
837 | parg->offset = tp->size; | |
838 | tp->size += parg->type->size; | |
e09c8614 MH |
839 | ret = __parse_probe_arg(arg, parg->type, &parg->fetch, is_return); |
840 | if (ret >= 0) { | |
841 | parg->fetch_size.fn = get_fetch_size_function(parg->type, | |
842 | parg->fetch.fn); | |
843 | parg->fetch_size.data = parg->fetch.data; | |
844 | } | |
845 | return ret; | |
ba8665d7 MH |
846 | } |
847 | ||
a703d946 MH |
848 | /* Return 1 if name is reserved or already used by another argument */ |
849 | static int conflict_field_name(const char *name, | |
850 | struct probe_arg *args, int narg) | |
851 | { | |
852 | int i; | |
853 | for (i = 0; i < ARRAY_SIZE(reserved_field_names); i++) | |
854 | if (strcmp(reserved_field_names[i], name) == 0) | |
855 | return 1; | |
856 | for (i = 0; i < narg; i++) | |
857 | if (strcmp(args[i].name, name) == 0) | |
858 | return 1; | |
859 | return 0; | |
860 | } | |
861 | ||
413d37d1 MH |
862 | static int create_trace_probe(int argc, char **argv) |
863 | { | |
864 | /* | |
865 | * Argument syntax: | |
f52487e9 MH |
866 | * - Add kprobe: p[:[GRP/]EVENT] KSYM[+OFFS]|KADDR [FETCHARGS] |
867 | * - Add kretprobe: r[:[GRP/]EVENT] KSYM[+0] [FETCHARGS] | |
413d37d1 | 868 | * Fetch args: |
2e06ff63 MH |
869 | * $retval : fetch return value |
870 | * $stack : fetch stack address | |
871 | * $stackN : fetch Nth of stack (N:0-) | |
413d37d1 MH |
872 | * @ADDR : fetch memory at ADDR (ADDR should be in kernel) |
873 | * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol) | |
874 | * %REG : fetch register REG | |
93ccae7a | 875 | * Dereferencing memory fetch: |
413d37d1 | 876 | * +|-offs(ARG) : fetch memory at ARG +|- offs address. |
eca0d916 MH |
877 | * Alias name of args: |
878 | * NAME=FETCHARG : set NAME as alias of FETCHARG. | |
93ccae7a MH |
879 | * Type of args: |
880 | * FETCHARG:TYPE : use TYPE instead of unsigned long. | |
413d37d1 MH |
881 | */ |
882 | struct trace_probe *tp; | |
413d37d1 | 883 | int i, ret = 0; |
a7c312be | 884 | int is_return = 0, is_delete = 0; |
93ccae7a MH |
885 | char *symbol = NULL, *event = NULL, *group = NULL; |
886 | char *arg, *tmp; | |
2fba0c88 | 887 | unsigned long offset = 0; |
413d37d1 | 888 | void *addr = NULL; |
4a846b44 | 889 | char buf[MAX_EVENT_NAME_LEN]; |
413d37d1 | 890 | |
a7c312be | 891 | /* argc must be >= 1 */ |
413d37d1 MH |
892 | if (argv[0][0] == 'p') |
893 | is_return = 0; | |
894 | else if (argv[0][0] == 'r') | |
895 | is_return = 1; | |
a7c312be MH |
896 | else if (argv[0][0] == '-') |
897 | is_delete = 1; | |
e63cc239 | 898 | else { |
a7c312be MH |
899 | pr_info("Probe definition must be started with 'p', 'r' or" |
900 | " '-'.\n"); | |
413d37d1 | 901 | return -EINVAL; |
e63cc239 | 902 | } |
413d37d1 MH |
903 | |
904 | if (argv[0][1] == ':') { | |
905 | event = &argv[0][2]; | |
f52487e9 MH |
906 | if (strchr(event, '/')) { |
907 | group = event; | |
908 | event = strchr(group, '/') + 1; | |
909 | event[-1] = '\0'; | |
910 | if (strlen(group) == 0) { | |
a5efd925 | 911 | pr_info("Group name is not specified\n"); |
f52487e9 MH |
912 | return -EINVAL; |
913 | } | |
914 | } | |
413d37d1 | 915 | if (strlen(event) == 0) { |
a5efd925 | 916 | pr_info("Event name is not specified\n"); |
413d37d1 MH |
917 | return -EINVAL; |
918 | } | |
919 | } | |
a7c312be MH |
920 | if (!group) |
921 | group = KPROBE_EVENT_SYSTEM; | |
413d37d1 | 922 | |
a7c312be MH |
923 | if (is_delete) { |
924 | if (!event) { | |
925 | pr_info("Delete command needs an event name.\n"); | |
926 | return -EINVAL; | |
927 | } | |
928 | tp = find_probe_event(event, group); | |
929 | if (!tp) { | |
930 | pr_info("Event %s/%s doesn't exist.\n", group, event); | |
931 | return -ENOENT; | |
932 | } | |
933 | /* delete an event */ | |
934 | unregister_trace_probe(tp); | |
935 | free_trace_probe(tp); | |
936 | return 0; | |
937 | } | |
938 | ||
939 | if (argc < 2) { | |
940 | pr_info("Probe point is not specified.\n"); | |
941 | return -EINVAL; | |
942 | } | |
413d37d1 | 943 | if (isdigit(argv[1][0])) { |
e63cc239 MH |
944 | if (is_return) { |
945 | pr_info("Return probe point must be a symbol.\n"); | |
413d37d1 | 946 | return -EINVAL; |
e63cc239 | 947 | } |
413d37d1 | 948 | /* an address specified */ |
a9bb18f3 | 949 | ret = strict_strtoul(&argv[1][0], 0, (unsigned long *)&addr); |
e63cc239 MH |
950 | if (ret) { |
951 | pr_info("Failed to parse address.\n"); | |
413d37d1 | 952 | return ret; |
e63cc239 | 953 | } |
413d37d1 MH |
954 | } else { |
955 | /* a symbol specified */ | |
956 | symbol = argv[1]; | |
957 | /* TODO: support .init module functions */ | |
958 | ret = split_symbol_offset(symbol, &offset); | |
e63cc239 MH |
959 | if (ret) { |
960 | pr_info("Failed to parse symbol.\n"); | |
413d37d1 | 961 | return ret; |
e63cc239 MH |
962 | } |
963 | if (offset && is_return) { | |
964 | pr_info("Return probe must be used without offset.\n"); | |
413d37d1 | 965 | return -EINVAL; |
e63cc239 | 966 | } |
413d37d1 | 967 | } |
a82378d8 | 968 | argc -= 2; argv += 2; |
413d37d1 MH |
969 | |
970 | /* setup a probe */ | |
4263565d MH |
971 | if (!event) { |
972 | /* Make a new event name */ | |
4263565d | 973 | if (symbol) |
6f3cf440 | 974 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld", |
4263565d MH |
975 | is_return ? 'r' : 'p', symbol, offset); |
976 | else | |
6f3cf440 | 977 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p", |
4263565d | 978 | is_return ? 'r' : 'p', addr); |
4a846b44 MH |
979 | event = buf; |
980 | } | |
f52487e9 MH |
981 | tp = alloc_trace_probe(group, event, addr, symbol, offset, argc, |
982 | is_return); | |
e63cc239 MH |
983 | if (IS_ERR(tp)) { |
984 | pr_info("Failed to allocate trace_probe.(%d)\n", | |
985 | (int)PTR_ERR(tp)); | |
413d37d1 | 986 | return PTR_ERR(tp); |
e63cc239 | 987 | } |
413d37d1 | 988 | |
413d37d1 | 989 | /* parse arguments */ |
a82378d8 MH |
990 | ret = 0; |
991 | for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { | |
eca0d916 MH |
992 | /* Parse argument name */ |
993 | arg = strchr(argv[i], '='); | |
994 | if (arg) | |
995 | *arg++ = '\0'; | |
996 | else | |
997 | arg = argv[i]; | |
a703d946 | 998 | |
eca0d916 | 999 | tp->args[i].name = kstrdup(argv[i], GFP_KERNEL); |
ba8665d7 MH |
1000 | if (!tp->args[i].name) { |
1001 | pr_info("Failed to allocate argument%d name '%s'.\n", | |
1002 | i, argv[i]); | |
1003 | ret = -ENOMEM; | |
413d37d1 MH |
1004 | goto error; |
1005 | } | |
93ccae7a MH |
1006 | tmp = strchr(tp->args[i].name, ':'); |
1007 | if (tmp) | |
1008 | *tmp = '_'; /* convert : to _ */ | |
1009 | ||
1010 | if (conflict_field_name(tp->args[i].name, tp->args, i)) { | |
1011 | pr_info("Argument%d name '%s' conflicts with " | |
1012 | "another field.\n", i, argv[i]); | |
1013 | ret = -EINVAL; | |
1014 | goto error; | |
1015 | } | |
ba8665d7 MH |
1016 | |
1017 | /* Parse fetch argument */ | |
93ccae7a | 1018 | ret = parse_probe_arg(arg, tp, &tp->args[i], is_return); |
e63cc239 MH |
1019 | if (ret) { |
1020 | pr_info("Parse error at argument%d. (%d)\n", i, ret); | |
abab9d37 | 1021 | kfree(tp->args[i].name); |
413d37d1 | 1022 | goto error; |
e63cc239 | 1023 | } |
abab9d37 LJ |
1024 | |
1025 | tp->nr_args++; | |
413d37d1 | 1026 | } |
413d37d1 MH |
1027 | |
1028 | ret = register_trace_probe(tp); | |
1029 | if (ret) | |
1030 | goto error; | |
1031 | return 0; | |
1032 | ||
1033 | error: | |
1034 | free_trace_probe(tp); | |
1035 | return ret; | |
1036 | } | |
1037 | ||
1038 | static void cleanup_all_probes(void) | |
1039 | { | |
1040 | struct trace_probe *tp; | |
1041 | ||
1042 | mutex_lock(&probe_lock); | |
1043 | /* TODO: Use batch unregistration */ | |
1044 | while (!list_empty(&probe_list)) { | |
1045 | tp = list_entry(probe_list.next, struct trace_probe, list); | |
1046 | unregister_trace_probe(tp); | |
1047 | free_trace_probe(tp); | |
1048 | } | |
1049 | mutex_unlock(&probe_lock); | |
1050 | } | |
1051 | ||
1052 | ||
1053 | /* Probes listing interfaces */ | |
1054 | static void *probes_seq_start(struct seq_file *m, loff_t *pos) | |
1055 | { | |
1056 | mutex_lock(&probe_lock); | |
1057 | return seq_list_start(&probe_list, *pos); | |
1058 | } | |
1059 | ||
1060 | static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos) | |
1061 | { | |
1062 | return seq_list_next(v, &probe_list, pos); | |
1063 | } | |
1064 | ||
1065 | static void probes_seq_stop(struct seq_file *m, void *v) | |
1066 | { | |
1067 | mutex_unlock(&probe_lock); | |
1068 | } | |
1069 | ||
1070 | static int probes_seq_show(struct seq_file *m, void *v) | |
1071 | { | |
1072 | struct trace_probe *tp = v; | |
93ccae7a | 1073 | int i; |
413d37d1 MH |
1074 | |
1075 | seq_printf(m, "%c", probe_is_return(tp) ? 'r' : 'p'); | |
8f082018 | 1076 | seq_printf(m, ":%s/%s", tp->call.class->system, tp->call.name); |
413d37d1 | 1077 | |
52a11f35 LJ |
1078 | if (!tp->symbol) |
1079 | seq_printf(m, " 0x%p", tp->rp.kp.addr); | |
1080 | else if (tp->rp.kp.offset) | |
4a846b44 | 1081 | seq_printf(m, " %s+%u", probe_symbol(tp), tp->rp.kp.offset); |
413d37d1 | 1082 | else |
52a11f35 | 1083 | seq_printf(m, " %s", probe_symbol(tp)); |
413d37d1 | 1084 | |
93ccae7a MH |
1085 | for (i = 0; i < tp->nr_args; i++) |
1086 | seq_printf(m, " %s=%s", tp->args[i].name, tp->args[i].comm); | |
413d37d1 | 1087 | seq_printf(m, "\n"); |
93ccae7a | 1088 | |
413d37d1 MH |
1089 | return 0; |
1090 | } | |
1091 | ||
1092 | static const struct seq_operations probes_seq_op = { | |
1093 | .start = probes_seq_start, | |
1094 | .next = probes_seq_next, | |
1095 | .stop = probes_seq_stop, | |
1096 | .show = probes_seq_show | |
1097 | }; | |
1098 | ||
1099 | static int probes_open(struct inode *inode, struct file *file) | |
1100 | { | |
1101 | if ((file->f_mode & FMODE_WRITE) && | |
1102 | (file->f_flags & O_TRUNC)) | |
1103 | cleanup_all_probes(); | |
1104 | ||
1105 | return seq_open(file, &probes_seq_op); | |
1106 | } | |
1107 | ||
1108 | static int command_trace_probe(const char *buf) | |
1109 | { | |
1110 | char **argv; | |
1111 | int argc = 0, ret = 0; | |
1112 | ||
1113 | argv = argv_split(GFP_KERNEL, buf, &argc); | |
1114 | if (!argv) | |
1115 | return -ENOMEM; | |
1116 | ||
1117 | if (argc) | |
1118 | ret = create_trace_probe(argc, argv); | |
1119 | ||
1120 | argv_free(argv); | |
1121 | return ret; | |
1122 | } | |
1123 | ||
1124 | #define WRITE_BUFSIZE 128 | |
1125 | ||
1126 | static ssize_t probes_write(struct file *file, const char __user *buffer, | |
1127 | size_t count, loff_t *ppos) | |
1128 | { | |
1129 | char *kbuf, *tmp; | |
1130 | int ret; | |
1131 | size_t done; | |
1132 | size_t size; | |
1133 | ||
1134 | kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL); | |
1135 | if (!kbuf) | |
1136 | return -ENOMEM; | |
1137 | ||
1138 | ret = done = 0; | |
1139 | while (done < count) { | |
1140 | size = count - done; | |
1141 | if (size >= WRITE_BUFSIZE) | |
1142 | size = WRITE_BUFSIZE - 1; | |
1143 | if (copy_from_user(kbuf, buffer + done, size)) { | |
1144 | ret = -EFAULT; | |
1145 | goto out; | |
1146 | } | |
1147 | kbuf[size] = '\0'; | |
1148 | tmp = strchr(kbuf, '\n'); | |
1149 | if (tmp) { | |
1150 | *tmp = '\0'; | |
1151 | size = tmp - kbuf + 1; | |
1152 | } else if (done + size < count) { | |
1153 | pr_warning("Line length is too long: " | |
1154 | "Should be less than %d.", WRITE_BUFSIZE); | |
1155 | ret = -EINVAL; | |
1156 | goto out; | |
1157 | } | |
1158 | done += size; | |
1159 | /* Remove comments */ | |
1160 | tmp = strchr(kbuf, '#'); | |
1161 | if (tmp) | |
1162 | *tmp = '\0'; | |
1163 | ||
1164 | ret = command_trace_probe(kbuf); | |
1165 | if (ret) | |
1166 | goto out; | |
1167 | } | |
1168 | ret = done; | |
1169 | out: | |
1170 | kfree(kbuf); | |
1171 | return ret; | |
1172 | } | |
1173 | ||
1174 | static const struct file_operations kprobe_events_ops = { | |
1175 | .owner = THIS_MODULE, | |
1176 | .open = probes_open, | |
1177 | .read = seq_read, | |
1178 | .llseek = seq_lseek, | |
1179 | .release = seq_release, | |
1180 | .write = probes_write, | |
1181 | }; | |
1182 | ||
cd7e7bd5 MH |
1183 | /* Probes profiling interfaces */ |
1184 | static int probes_profile_seq_show(struct seq_file *m, void *v) | |
1185 | { | |
1186 | struct trace_probe *tp = v; | |
1187 | ||
1188 | seq_printf(m, " %-44s %15lu %15lu\n", tp->call.name, tp->nhit, | |
4a846b44 | 1189 | tp->rp.kp.nmissed); |
cd7e7bd5 MH |
1190 | |
1191 | return 0; | |
1192 | } | |
1193 | ||
1194 | static const struct seq_operations profile_seq_op = { | |
1195 | .start = probes_seq_start, | |
1196 | .next = probes_seq_next, | |
1197 | .stop = probes_seq_stop, | |
1198 | .show = probes_profile_seq_show | |
1199 | }; | |
1200 | ||
1201 | static int profile_open(struct inode *inode, struct file *file) | |
1202 | { | |
1203 | return seq_open(file, &profile_seq_op); | |
1204 | } | |
1205 | ||
1206 | static const struct file_operations kprobe_profile_ops = { | |
1207 | .owner = THIS_MODULE, | |
1208 | .open = profile_open, | |
1209 | .read = seq_read, | |
1210 | .llseek = seq_lseek, | |
1211 | .release = seq_release, | |
1212 | }; | |
1213 | ||
e09c8614 MH |
1214 | /* Sum up total data length for dynamic arraies (strings) */ |
1215 | static __kprobes int __get_data_size(struct trace_probe *tp, | |
1216 | struct pt_regs *regs) | |
1217 | { | |
1218 | int i, ret = 0; | |
1219 | u32 len; | |
1220 | ||
1221 | for (i = 0; i < tp->nr_args; i++) | |
1222 | if (unlikely(tp->args[i].fetch_size.fn)) { | |
1223 | call_fetch(&tp->args[i].fetch_size, regs, &len); | |
1224 | ret += len; | |
1225 | } | |
1226 | ||
1227 | return ret; | |
1228 | } | |
1229 | ||
1230 | /* Store the value of each argument */ | |
1231 | static __kprobes void store_trace_args(int ent_size, struct trace_probe *tp, | |
1232 | struct pt_regs *regs, | |
1233 | u8 *data, int maxlen) | |
1234 | { | |
1235 | int i; | |
1236 | u32 end = tp->size; | |
1237 | u32 *dl; /* Data (relative) location */ | |
1238 | ||
1239 | for (i = 0; i < tp->nr_args; i++) { | |
1240 | if (unlikely(tp->args[i].fetch_size.fn)) { | |
1241 | /* | |
1242 | * First, we set the relative location and | |
1243 | * maximum data length to *dl | |
1244 | */ | |
1245 | dl = (u32 *)(data + tp->args[i].offset); | |
1246 | *dl = make_data_rloc(maxlen, end - tp->args[i].offset); | |
1247 | /* Then try to fetch string or dynamic array data */ | |
1248 | call_fetch(&tp->args[i].fetch, regs, dl); | |
1249 | /* Reduce maximum length */ | |
1250 | end += get_rloc_len(*dl); | |
1251 | maxlen -= get_rloc_len(*dl); | |
1252 | /* Trick here, convert data_rloc to data_loc */ | |
1253 | *dl = convert_rloc_to_loc(*dl, | |
1254 | ent_size + tp->args[i].offset); | |
1255 | } else | |
1256 | /* Just fetching data normally */ | |
1257 | call_fetch(&tp->args[i].fetch, regs, | |
1258 | data + tp->args[i].offset); | |
1259 | } | |
1260 | } | |
1261 | ||
413d37d1 | 1262 | /* Kprobe handler */ |
1e12a4a7 | 1263 | static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs) |
413d37d1 | 1264 | { |
4a846b44 | 1265 | struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); |
93ccae7a | 1266 | struct kprobe_trace_entry_head *entry; |
413d37d1 | 1267 | struct ring_buffer_event *event; |
8f8ffe24 | 1268 | struct ring_buffer *buffer; |
e09c8614 | 1269 | int size, dsize, pc; |
413d37d1 | 1270 | unsigned long irq_flags; |
4263565d | 1271 | struct ftrace_event_call *call = &tp->call; |
413d37d1 | 1272 | |
cd7e7bd5 MH |
1273 | tp->nhit++; |
1274 | ||
413d37d1 MH |
1275 | local_save_flags(irq_flags); |
1276 | pc = preempt_count(); | |
1277 | ||
e09c8614 MH |
1278 | dsize = __get_data_size(tp, regs); |
1279 | size = sizeof(*entry) + tp->size + dsize; | |
413d37d1 | 1280 | |
32c0edae SR |
1281 | event = trace_current_buffer_lock_reserve(&buffer, call->event.type, |
1282 | size, irq_flags, pc); | |
413d37d1 | 1283 | if (!event) |
1e12a4a7 | 1284 | return; |
413d37d1 MH |
1285 | |
1286 | entry = ring_buffer_event_data(event); | |
413d37d1 | 1287 | entry->ip = (unsigned long)kp->addr; |
e09c8614 | 1288 | store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); |
413d37d1 | 1289 | |
8f8ffe24 FW |
1290 | if (!filter_current_check_discard(buffer, call, entry, event)) |
1291 | trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc); | |
413d37d1 MH |
1292 | } |
1293 | ||
1294 | /* Kretprobe handler */ | |
1e12a4a7 | 1295 | static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri, |
413d37d1 MH |
1296 | struct pt_regs *regs) |
1297 | { | |
1298 | struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); | |
93ccae7a | 1299 | struct kretprobe_trace_entry_head *entry; |
413d37d1 | 1300 | struct ring_buffer_event *event; |
8f8ffe24 | 1301 | struct ring_buffer *buffer; |
e09c8614 | 1302 | int size, pc, dsize; |
413d37d1 | 1303 | unsigned long irq_flags; |
4263565d | 1304 | struct ftrace_event_call *call = &tp->call; |
413d37d1 MH |
1305 | |
1306 | local_save_flags(irq_flags); | |
1307 | pc = preempt_count(); | |
1308 | ||
e09c8614 MH |
1309 | dsize = __get_data_size(tp, regs); |
1310 | size = sizeof(*entry) + tp->size + dsize; | |
413d37d1 | 1311 | |
32c0edae SR |
1312 | event = trace_current_buffer_lock_reserve(&buffer, call->event.type, |
1313 | size, irq_flags, pc); | |
413d37d1 | 1314 | if (!event) |
1e12a4a7 | 1315 | return; |
413d37d1 MH |
1316 | |
1317 | entry = ring_buffer_event_data(event); | |
4a846b44 | 1318 | entry->func = (unsigned long)tp->rp.kp.addr; |
413d37d1 | 1319 | entry->ret_ip = (unsigned long)ri->ret_addr; |
e09c8614 | 1320 | store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); |
413d37d1 | 1321 | |
8f8ffe24 FW |
1322 | if (!filter_current_check_discard(buffer, call, entry, event)) |
1323 | trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc); | |
413d37d1 MH |
1324 | } |
1325 | ||
1326 | /* Event entry printers */ | |
1327 | enum print_line_t | |
a9a57763 SR |
1328 | print_kprobe_event(struct trace_iterator *iter, int flags, |
1329 | struct trace_event *event) | |
413d37d1 | 1330 | { |
93ccae7a | 1331 | struct kprobe_trace_entry_head *field; |
413d37d1 | 1332 | struct trace_seq *s = &iter->seq; |
eca0d916 | 1333 | struct trace_probe *tp; |
93ccae7a | 1334 | u8 *data; |
413d37d1 MH |
1335 | int i; |
1336 | ||
93ccae7a | 1337 | field = (struct kprobe_trace_entry_head *)iter->ent; |
80decc70 | 1338 | tp = container_of(event, struct trace_probe, call.event); |
413d37d1 | 1339 | |
6e9f23d1 MH |
1340 | if (!trace_seq_printf(s, "%s: (", tp->call.name)) |
1341 | goto partial; | |
1342 | ||
413d37d1 MH |
1343 | if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET)) |
1344 | goto partial; | |
1345 | ||
6e9f23d1 | 1346 | if (!trace_seq_puts(s, ")")) |
413d37d1 MH |
1347 | goto partial; |
1348 | ||
93ccae7a MH |
1349 | data = (u8 *)&field[1]; |
1350 | for (i = 0; i < tp->nr_args; i++) | |
1351 | if (!tp->args[i].type->print(s, tp->args[i].name, | |
e09c8614 | 1352 | data + tp->args[i].offset, field)) |
413d37d1 MH |
1353 | goto partial; |
1354 | ||
1355 | if (!trace_seq_puts(s, "\n")) | |
1356 | goto partial; | |
1357 | ||
1358 | return TRACE_TYPE_HANDLED; | |
1359 | partial: | |
1360 | return TRACE_TYPE_PARTIAL_LINE; | |
1361 | } | |
1362 | ||
1363 | enum print_line_t | |
a9a57763 SR |
1364 | print_kretprobe_event(struct trace_iterator *iter, int flags, |
1365 | struct trace_event *event) | |
413d37d1 | 1366 | { |
93ccae7a | 1367 | struct kretprobe_trace_entry_head *field; |
413d37d1 | 1368 | struct trace_seq *s = &iter->seq; |
eca0d916 | 1369 | struct trace_probe *tp; |
93ccae7a | 1370 | u8 *data; |
413d37d1 MH |
1371 | int i; |
1372 | ||
93ccae7a | 1373 | field = (struct kretprobe_trace_entry_head *)iter->ent; |
80decc70 | 1374 | tp = container_of(event, struct trace_probe, call.event); |
413d37d1 | 1375 | |
6e9f23d1 MH |
1376 | if (!trace_seq_printf(s, "%s: (", tp->call.name)) |
1377 | goto partial; | |
1378 | ||
413d37d1 MH |
1379 | if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET)) |
1380 | goto partial; | |
1381 | ||
1382 | if (!trace_seq_puts(s, " <- ")) | |
1383 | goto partial; | |
1384 | ||
1385 | if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET)) | |
1386 | goto partial; | |
1387 | ||
6e9f23d1 | 1388 | if (!trace_seq_puts(s, ")")) |
413d37d1 MH |
1389 | goto partial; |
1390 | ||
93ccae7a MH |
1391 | data = (u8 *)&field[1]; |
1392 | for (i = 0; i < tp->nr_args; i++) | |
1393 | if (!tp->args[i].type->print(s, tp->args[i].name, | |
e09c8614 | 1394 | data + tp->args[i].offset, field)) |
413d37d1 MH |
1395 | goto partial; |
1396 | ||
1397 | if (!trace_seq_puts(s, "\n")) | |
1398 | goto partial; | |
1399 | ||
1400 | return TRACE_TYPE_HANDLED; | |
1401 | partial: | |
1402 | return TRACE_TYPE_PARTIAL_LINE; | |
1403 | } | |
1404 | ||
413d37d1 MH |
1405 | static int probe_event_enable(struct ftrace_event_call *call) |
1406 | { | |
1407 | struct trace_probe *tp = (struct trace_probe *)call->data; | |
1408 | ||
50d78056 MH |
1409 | tp->flags |= TP_FLAG_TRACE; |
1410 | if (probe_is_return(tp)) | |
413d37d1 | 1411 | return enable_kretprobe(&tp->rp); |
50d78056 | 1412 | else |
4a846b44 | 1413 | return enable_kprobe(&tp->rp.kp); |
413d37d1 MH |
1414 | } |
1415 | ||
1416 | static void probe_event_disable(struct ftrace_event_call *call) | |
1417 | { | |
1418 | struct trace_probe *tp = (struct trace_probe *)call->data; | |
1419 | ||
50d78056 MH |
1420 | tp->flags &= ~TP_FLAG_TRACE; |
1421 | if (!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE))) { | |
1422 | if (probe_is_return(tp)) | |
1423 | disable_kretprobe(&tp->rp); | |
1424 | else | |
1425 | disable_kprobe(&tp->rp.kp); | |
1426 | } | |
413d37d1 MH |
1427 | } |
1428 | ||
413d37d1 MH |
1429 | #undef DEFINE_FIELD |
1430 | #define DEFINE_FIELD(type, item, name, is_signed) \ | |
1431 | do { \ | |
1432 | ret = trace_define_field(event_call, #type, name, \ | |
1433 | offsetof(typeof(field), item), \ | |
1434 | sizeof(field.item), is_signed, \ | |
1435 | FILTER_OTHER); \ | |
1436 | if (ret) \ | |
1437 | return ret; \ | |
1438 | } while (0) | |
1439 | ||
1440 | static int kprobe_event_define_fields(struct ftrace_event_call *event_call) | |
1441 | { | |
1442 | int ret, i; | |
93ccae7a | 1443 | struct kprobe_trace_entry_head field; |
413d37d1 MH |
1444 | struct trace_probe *tp = (struct trace_probe *)event_call->data; |
1445 | ||
a703d946 | 1446 | DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0); |
eca0d916 | 1447 | /* Set argument names as fields */ |
93ccae7a | 1448 | for (i = 0; i < tp->nr_args; i++) { |
e09c8614 | 1449 | ret = trace_define_field(event_call, tp->args[i].type->fmttype, |
93ccae7a MH |
1450 | tp->args[i].name, |
1451 | sizeof(field) + tp->args[i].offset, | |
1452 | tp->args[i].type->size, | |
1453 | tp->args[i].type->is_signed, | |
1454 | FILTER_OTHER); | |
1455 | if (ret) | |
1456 | return ret; | |
1457 | } | |
413d37d1 MH |
1458 | return 0; |
1459 | } | |
1460 | ||
1461 | static int kretprobe_event_define_fields(struct ftrace_event_call *event_call) | |
1462 | { | |
1463 | int ret, i; | |
93ccae7a | 1464 | struct kretprobe_trace_entry_head field; |
413d37d1 MH |
1465 | struct trace_probe *tp = (struct trace_probe *)event_call->data; |
1466 | ||
a703d946 MH |
1467 | DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0); |
1468 | DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0); | |
eca0d916 | 1469 | /* Set argument names as fields */ |
93ccae7a | 1470 | for (i = 0; i < tp->nr_args; i++) { |
e09c8614 | 1471 | ret = trace_define_field(event_call, tp->args[i].type->fmttype, |
93ccae7a MH |
1472 | tp->args[i].name, |
1473 | sizeof(field) + tp->args[i].offset, | |
1474 | tp->args[i].type->size, | |
1475 | tp->args[i].type->is_signed, | |
1476 | FILTER_OTHER); | |
1477 | if (ret) | |
1478 | return ret; | |
1479 | } | |
413d37d1 MH |
1480 | return 0; |
1481 | } | |
1482 | ||
a342a028 LJ |
1483 | static int __set_print_fmt(struct trace_probe *tp, char *buf, int len) |
1484 | { | |
1485 | int i; | |
1486 | int pos = 0; | |
1487 | ||
1488 | const char *fmt, *arg; | |
1489 | ||
1490 | if (!probe_is_return(tp)) { | |
1491 | fmt = "(%lx)"; | |
1492 | arg = "REC->" FIELD_STRING_IP; | |
1493 | } else { | |
1494 | fmt = "(%lx <- %lx)"; | |
1495 | arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP; | |
1496 | } | |
1497 | ||
1498 | /* When len=0, we just calculate the needed length */ | |
1499 | #define LEN_OR_ZERO (len ? len - pos : 0) | |
1500 | ||
1501 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt); | |
1502 | ||
1503 | for (i = 0; i < tp->nr_args; i++) { | |
93ccae7a MH |
1504 | pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s", |
1505 | tp->args[i].name, tp->args[i].type->fmt); | |
a342a028 LJ |
1506 | } |
1507 | ||
1508 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg); | |
1509 | ||
1510 | for (i = 0; i < tp->nr_args; i++) { | |
e09c8614 MH |
1511 | if (strcmp(tp->args[i].type->name, "string") == 0) |
1512 | pos += snprintf(buf + pos, LEN_OR_ZERO, | |
1513 | ", __get_str(%s)", | |
1514 | tp->args[i].name); | |
1515 | else | |
1516 | pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s", | |
1517 | tp->args[i].name); | |
a342a028 LJ |
1518 | } |
1519 | ||
1520 | #undef LEN_OR_ZERO | |
1521 | ||
1522 | /* return the length of print_fmt */ | |
1523 | return pos; | |
1524 | } | |
1525 | ||
1526 | static int set_print_fmt(struct trace_probe *tp) | |
1527 | { | |
1528 | int len; | |
1529 | char *print_fmt; | |
1530 | ||
1531 | /* First: called with 0 length to calculate the needed length */ | |
1532 | len = __set_print_fmt(tp, NULL, 0); | |
1533 | print_fmt = kmalloc(len + 1, GFP_KERNEL); | |
1534 | if (!print_fmt) | |
1535 | return -ENOMEM; | |
1536 | ||
1537 | /* Second: actually write the @print_fmt */ | |
1538 | __set_print_fmt(tp, print_fmt, len + 1); | |
1539 | tp->call.print_fmt = print_fmt; | |
1540 | ||
1541 | return 0; | |
1542 | } | |
1543 | ||
07b139c8 | 1544 | #ifdef CONFIG_PERF_EVENTS |
e08d1c65 MH |
1545 | |
1546 | /* Kprobe profile handler */ | |
97d5a220 | 1547 | static __kprobes void kprobe_perf_func(struct kprobe *kp, |
e08d1c65 MH |
1548 | struct pt_regs *regs) |
1549 | { | |
1550 | struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); | |
1551 | struct ftrace_event_call *call = &tp->call; | |
93ccae7a | 1552 | struct kprobe_trace_entry_head *entry; |
1c024eca | 1553 | struct hlist_head *head; |
e09c8614 | 1554 | int size, __size, dsize; |
4ed7c92d | 1555 | int rctx; |
e08d1c65 | 1556 | |
e09c8614 MH |
1557 | dsize = __get_data_size(tp, regs); |
1558 | __size = sizeof(*entry) + tp->size + dsize; | |
74ebb63e MH |
1559 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
1560 | size -= sizeof(u32); | |
97d5a220 | 1561 | if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, |
a1a138d0 | 1562 | "profile buffer not large enough")) |
1e12a4a7 | 1563 | return; |
ce71b9df | 1564 | |
ff5f149b | 1565 | entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx); |
430ad5a6 | 1566 | if (!entry) |
1e12a4a7 | 1567 | return; |
a1a138d0 | 1568 | |
a1a138d0 | 1569 | entry->ip = (unsigned long)kp->addr; |
e09c8614 MH |
1570 | memset(&entry[1], 0, dsize); |
1571 | store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); | |
444a2a3b | 1572 | |
3771f077 | 1573 | head = this_cpu_ptr(call->perf_events); |
1c024eca | 1574 | perf_trace_buf_submit(entry, size, rctx, entry->ip, 1, regs, head); |
e08d1c65 MH |
1575 | } |
1576 | ||
1577 | /* Kretprobe profile handler */ | |
97d5a220 | 1578 | static __kprobes void kretprobe_perf_func(struct kretprobe_instance *ri, |
e08d1c65 MH |
1579 | struct pt_regs *regs) |
1580 | { | |
1581 | struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); | |
1582 | struct ftrace_event_call *call = &tp->call; | |
93ccae7a | 1583 | struct kretprobe_trace_entry_head *entry; |
1c024eca | 1584 | struct hlist_head *head; |
e09c8614 | 1585 | int size, __size, dsize; |
4ed7c92d | 1586 | int rctx; |
e08d1c65 | 1587 | |
e09c8614 MH |
1588 | dsize = __get_data_size(tp, regs); |
1589 | __size = sizeof(*entry) + tp->size + dsize; | |
74ebb63e MH |
1590 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
1591 | size -= sizeof(u32); | |
97d5a220 | 1592 | if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, |
a1a138d0 | 1593 | "profile buffer not large enough")) |
1e12a4a7 | 1594 | return; |
444a2a3b | 1595 | |
ff5f149b | 1596 | entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx); |
430ad5a6 | 1597 | if (!entry) |
1e12a4a7 | 1598 | return; |
e08d1c65 | 1599 | |
a1a138d0 MH |
1600 | entry->func = (unsigned long)tp->rp.kp.addr; |
1601 | entry->ret_ip = (unsigned long)ri->ret_addr; | |
e09c8614 | 1602 | store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); |
444a2a3b | 1603 | |
3771f077 | 1604 | head = this_cpu_ptr(call->perf_events); |
1c024eca | 1605 | perf_trace_buf_submit(entry, size, rctx, entry->ret_ip, 1, regs, head); |
e08d1c65 MH |
1606 | } |
1607 | ||
97d5a220 | 1608 | static int probe_perf_enable(struct ftrace_event_call *call) |
e08d1c65 MH |
1609 | { |
1610 | struct trace_probe *tp = (struct trace_probe *)call->data; | |
1611 | ||
50d78056 | 1612 | tp->flags |= TP_FLAG_PROFILE; |
d7a4b414 | 1613 | |
50d78056 | 1614 | if (probe_is_return(tp)) |
e08d1c65 | 1615 | return enable_kretprobe(&tp->rp); |
50d78056 | 1616 | else |
e08d1c65 | 1617 | return enable_kprobe(&tp->rp.kp); |
e08d1c65 MH |
1618 | } |
1619 | ||
97d5a220 | 1620 | static void probe_perf_disable(struct ftrace_event_call *call) |
e08d1c65 | 1621 | { |
50d78056 MH |
1622 | struct trace_probe *tp = (struct trace_probe *)call->data; |
1623 | ||
d7a4b414 | 1624 | tp->flags &= ~TP_FLAG_PROFILE; |
50d78056 | 1625 | |
d7a4b414 | 1626 | if (!(tp->flags & TP_FLAG_TRACE)) { |
50d78056 MH |
1627 | if (probe_is_return(tp)) |
1628 | disable_kretprobe(&tp->rp); | |
1629 | else | |
1630 | disable_kprobe(&tp->rp.kp); | |
1631 | } | |
e08d1c65 | 1632 | } |
07b139c8 | 1633 | #endif /* CONFIG_PERF_EVENTS */ |
50d78056 | 1634 | |
2239291a SR |
1635 | static __kprobes |
1636 | int kprobe_register(struct ftrace_event_call *event, enum trace_reg type) | |
1637 | { | |
1638 | switch (type) { | |
1639 | case TRACE_REG_REGISTER: | |
1640 | return probe_event_enable(event); | |
1641 | case TRACE_REG_UNREGISTER: | |
1642 | probe_event_disable(event); | |
1643 | return 0; | |
1644 | ||
1645 | #ifdef CONFIG_PERF_EVENTS | |
1646 | case TRACE_REG_PERF_REGISTER: | |
1647 | return probe_perf_enable(event); | |
1648 | case TRACE_REG_PERF_UNREGISTER: | |
1649 | probe_perf_disable(event); | |
1650 | return 0; | |
1651 | #endif | |
1652 | } | |
1653 | return 0; | |
1654 | } | |
50d78056 MH |
1655 | |
1656 | static __kprobes | |
1657 | int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) | |
1658 | { | |
1659 | struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); | |
e08d1c65 | 1660 | |
50d78056 MH |
1661 | if (tp->flags & TP_FLAG_TRACE) |
1662 | kprobe_trace_func(kp, regs); | |
07b139c8 | 1663 | #ifdef CONFIG_PERF_EVENTS |
50d78056 | 1664 | if (tp->flags & TP_FLAG_PROFILE) |
97d5a220 | 1665 | kprobe_perf_func(kp, regs); |
07b139c8 | 1666 | #endif |
50d78056 MH |
1667 | return 0; /* We don't tweek kernel, so just return 0 */ |
1668 | } | |
1669 | ||
1670 | static __kprobes | |
1671 | int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) | |
1672 | { | |
1673 | struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); | |
1674 | ||
1675 | if (tp->flags & TP_FLAG_TRACE) | |
1676 | kretprobe_trace_func(ri, regs); | |
07b139c8 | 1677 | #ifdef CONFIG_PERF_EVENTS |
50d78056 | 1678 | if (tp->flags & TP_FLAG_PROFILE) |
97d5a220 | 1679 | kretprobe_perf_func(ri, regs); |
07b139c8 | 1680 | #endif |
50d78056 MH |
1681 | return 0; /* We don't tweek kernel, so just return 0 */ |
1682 | } | |
e08d1c65 | 1683 | |
a9a57763 SR |
1684 | static struct trace_event_functions kretprobe_funcs = { |
1685 | .trace = print_kretprobe_event | |
1686 | }; | |
1687 | ||
1688 | static struct trace_event_functions kprobe_funcs = { | |
1689 | .trace = print_kprobe_event | |
1690 | }; | |
1691 | ||
413d37d1 MH |
1692 | static int register_probe_event(struct trace_probe *tp) |
1693 | { | |
1694 | struct ftrace_event_call *call = &tp->call; | |
1695 | int ret; | |
1696 | ||
1697 | /* Initialize ftrace_event_call */ | |
ffb9f995 | 1698 | INIT_LIST_HEAD(&call->class->fields); |
413d37d1 | 1699 | if (probe_is_return(tp)) { |
80decc70 | 1700 | call->event.funcs = &kretprobe_funcs; |
2e33af02 | 1701 | call->class->define_fields = kretprobe_event_define_fields; |
413d37d1 | 1702 | } else { |
80decc70 | 1703 | call->event.funcs = &kprobe_funcs; |
2e33af02 | 1704 | call->class->define_fields = kprobe_event_define_fields; |
413d37d1 | 1705 | } |
a342a028 LJ |
1706 | if (set_print_fmt(tp) < 0) |
1707 | return -ENOMEM; | |
32c0edae SR |
1708 | ret = register_ftrace_event(&call->event); |
1709 | if (!ret) { | |
a342a028 | 1710 | kfree(call->print_fmt); |
ff50d991 | 1711 | return -ENODEV; |
a342a028 | 1712 | } |
553552ce | 1713 | call->flags = 0; |
2239291a | 1714 | call->class->reg = kprobe_register; |
413d37d1 MH |
1715 | call->data = tp; |
1716 | ret = trace_add_event_call(call); | |
ff50d991 | 1717 | if (ret) { |
413d37d1 | 1718 | pr_info("Failed to register kprobe event: %s\n", call->name); |
a342a028 | 1719 | kfree(call->print_fmt); |
80decc70 | 1720 | unregister_ftrace_event(&call->event); |
ff50d991 | 1721 | } |
413d37d1 MH |
1722 | return ret; |
1723 | } | |
1724 | ||
1725 | static void unregister_probe_event(struct trace_probe *tp) | |
1726 | { | |
ff50d991 | 1727 | /* tp->event is unregistered in trace_remove_event_call() */ |
413d37d1 | 1728 | trace_remove_event_call(&tp->call); |
a342a028 | 1729 | kfree(tp->call.print_fmt); |
413d37d1 MH |
1730 | } |
1731 | ||
1732 | /* Make a debugfs interface for controling probe points */ | |
1733 | static __init int init_kprobe_trace(void) | |
1734 | { | |
1735 | struct dentry *d_tracer; | |
1736 | struct dentry *entry; | |
413d37d1 MH |
1737 | |
1738 | d_tracer = tracing_init_dentry(); | |
1739 | if (!d_tracer) | |
1740 | return 0; | |
1741 | ||
1742 | entry = debugfs_create_file("kprobe_events", 0644, d_tracer, | |
1743 | NULL, &kprobe_events_ops); | |
1744 | ||
cd7e7bd5 | 1745 | /* Event list interface */ |
413d37d1 MH |
1746 | if (!entry) |
1747 | pr_warning("Could not create debugfs " | |
1748 | "'kprobe_events' entry\n"); | |
cd7e7bd5 MH |
1749 | |
1750 | /* Profile interface */ | |
1751 | entry = debugfs_create_file("kprobe_profile", 0444, d_tracer, | |
1752 | NULL, &kprobe_profile_ops); | |
1753 | ||
1754 | if (!entry) | |
1755 | pr_warning("Could not create debugfs " | |
1756 | "'kprobe_profile' entry\n"); | |
413d37d1 MH |
1757 | return 0; |
1758 | } | |
1759 | fs_initcall(init_kprobe_trace); | |
1760 | ||
1761 | ||
1762 | #ifdef CONFIG_FTRACE_STARTUP_TEST | |
1763 | ||
1764 | static int kprobe_trace_selftest_target(int a1, int a2, int a3, | |
1765 | int a4, int a5, int a6) | |
1766 | { | |
1767 | return a1 + a2 + a3 + a4 + a5 + a6; | |
1768 | } | |
1769 | ||
1770 | static __init int kprobe_trace_self_tests_init(void) | |
1771 | { | |
231e36f4 | 1772 | int ret, warn = 0; |
413d37d1 | 1773 | int (*target)(int, int, int, int, int, int); |
231e36f4 | 1774 | struct trace_probe *tp; |
413d37d1 MH |
1775 | |
1776 | target = kprobe_trace_selftest_target; | |
1777 | ||
1778 | pr_info("Testing kprobe tracing: "); | |
1779 | ||
1780 | ret = command_trace_probe("p:testprobe kprobe_trace_selftest_target " | |
231e36f4 MH |
1781 | "$stack $stack0 +0($stack)"); |
1782 | if (WARN_ON_ONCE(ret)) { | |
1783 | pr_warning("error on probing function entry.\n"); | |
1784 | warn++; | |
1785 | } else { | |
1786 | /* Enable trace point */ | |
1787 | tp = find_probe_event("testprobe", KPROBE_EVENT_SYSTEM); | |
1788 | if (WARN_ON_ONCE(tp == NULL)) { | |
1789 | pr_warning("error on getting new probe.\n"); | |
1790 | warn++; | |
1791 | } else | |
1792 | probe_event_enable(&tp->call); | |
1793 | } | |
413d37d1 MH |
1794 | |
1795 | ret = command_trace_probe("r:testprobe2 kprobe_trace_selftest_target " | |
f397af06 | 1796 | "$retval"); |
231e36f4 MH |
1797 | if (WARN_ON_ONCE(ret)) { |
1798 | pr_warning("error on probing function return.\n"); | |
1799 | warn++; | |
1800 | } else { | |
1801 | /* Enable trace point */ | |
1802 | tp = find_probe_event("testprobe2", KPROBE_EVENT_SYSTEM); | |
1803 | if (WARN_ON_ONCE(tp == NULL)) { | |
1804 | pr_warning("error on getting new probe.\n"); | |
1805 | warn++; | |
1806 | } else | |
1807 | probe_event_enable(&tp->call); | |
1808 | } | |
1809 | ||
1810 | if (warn) | |
1811 | goto end; | |
413d37d1 MH |
1812 | |
1813 | ret = target(1, 2, 3, 4, 5, 6); | |
1814 | ||
231e36f4 MH |
1815 | ret = command_trace_probe("-:testprobe"); |
1816 | if (WARN_ON_ONCE(ret)) { | |
1817 | pr_warning("error on deleting a probe.\n"); | |
1818 | warn++; | |
1819 | } | |
1820 | ||
1821 | ret = command_trace_probe("-:testprobe2"); | |
1822 | if (WARN_ON_ONCE(ret)) { | |
1823 | pr_warning("error on deleting a probe.\n"); | |
1824 | warn++; | |
1825 | } | |
413d37d1 | 1826 | |
231e36f4 MH |
1827 | end: |
1828 | cleanup_all_probes(); | |
1829 | if (warn) | |
1830 | pr_cont("NG: Some tests are failed. Please check them.\n"); | |
1831 | else | |
1832 | pr_cont("OK\n"); | |
413d37d1 MH |
1833 | return 0; |
1834 | } | |
1835 | ||
1836 | late_initcall(kprobe_trace_self_tests_init); | |
1837 | ||
1838 | #endif |