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Commit | Line | Data |
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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 | 33 | #include <linux/limits.h> |
93ccae7a | 34 | #include <asm/bitsperlong.h> |
413d37d1 MH |
35 | |
36 | #include "trace.h" | |
37 | #include "trace_output.h" | |
38 | ||
a82378d8 | 39 | #define MAX_TRACE_ARGS 128 |
413d37d1 | 40 | #define MAX_ARGSTR_LEN 63 |
4263565d | 41 | #define MAX_EVENT_NAME_LEN 64 |
e09c8614 | 42 | #define MAX_STRING_SIZE PATH_MAX |
f52487e9 | 43 | #define KPROBE_EVENT_SYSTEM "kprobes" |
413d37d1 | 44 | |
a703d946 | 45 | /* Reserved field names */ |
e93f4d85 | 46 | #define FIELD_STRING_IP "__probe_ip" |
e93f4d85 MH |
47 | #define FIELD_STRING_RETIP "__probe_ret_ip" |
48 | #define FIELD_STRING_FUNC "__probe_func" | |
a703d946 MH |
49 | |
50 | const char *reserved_field_names[] = { | |
51 | "common_type", | |
52 | "common_flags", | |
53 | "common_preempt_count", | |
54 | "common_pid", | |
55 | "common_tgid", | |
a703d946 | 56 | FIELD_STRING_IP, |
a703d946 MH |
57 | FIELD_STRING_RETIP, |
58 | FIELD_STRING_FUNC, | |
59 | }; | |
60 | ||
93ccae7a | 61 | /* Printing function type */ |
e09c8614 MH |
62 | typedef int (*print_type_func_t)(struct trace_seq *, const char *, void *, |
63 | void *); | |
93ccae7a MH |
64 | #define PRINT_TYPE_FUNC_NAME(type) print_type_##type |
65 | #define PRINT_TYPE_FMT_NAME(type) print_type_format_##type | |
66 | ||
67 | /* Printing in basic type function template */ | |
68 | #define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt, cast) \ | |
69 | static __kprobes int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, \ | |
e09c8614 MH |
70 | const char *name, \ |
71 | void *data, void *ent)\ | |
93ccae7a MH |
72 | { \ |
73 | return trace_seq_printf(s, " %s=" fmt, name, (cast)*(type *)data);\ | |
74 | } \ | |
75 | static const char PRINT_TYPE_FMT_NAME(type)[] = fmt; | |
76 | ||
77 | DEFINE_BASIC_PRINT_TYPE_FUNC(u8, "%x", unsigned int) | |
78 | DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "%x", unsigned int) | |
79 | DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "%lx", unsigned long) | |
80 | DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "%llx", unsigned long long) | |
81 | DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d", int) | |
82 | DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d", int) | |
83 | DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%ld", long) | |
84 | DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%lld", long long) | |
85 | ||
e09c8614 MH |
86 | /* data_rloc: data relative location, compatible with u32 */ |
87 | #define make_data_rloc(len, roffs) \ | |
88 | (((u32)(len) << 16) | ((u32)(roffs) & 0xffff)) | |
89 | #define get_rloc_len(dl) ((u32)(dl) >> 16) | |
90 | #define get_rloc_offs(dl) ((u32)(dl) & 0xffff) | |
91 | ||
92 | static inline void *get_rloc_data(u32 *dl) | |
93 | { | |
94 | return (u8 *)dl + get_rloc_offs(*dl); | |
95 | } | |
96 | ||
97 | /* For data_loc conversion */ | |
98 | static inline void *get_loc_data(u32 *dl, void *ent) | |
99 | { | |
100 | return (u8 *)ent + get_rloc_offs(*dl); | |
101 | } | |
102 | ||
103 | /* | |
104 | * Convert data_rloc to data_loc: | |
105 | * data_rloc stores the offset from data_rloc itself, but data_loc | |
106 | * stores the offset from event entry. | |
107 | */ | |
108 | #define convert_rloc_to_loc(dl, offs) ((u32)(dl) + (offs)) | |
109 | ||
110 | /* For defining macros, define string/string_size types */ | |
111 | typedef u32 string; | |
112 | typedef u32 string_size; | |
113 | ||
114 | /* Print type function for string type */ | |
115 | static __kprobes int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, | |
116 | const char *name, | |
117 | void *data, void *ent) | |
118 | { | |
119 | int len = *(u32 *)data >> 16; | |
120 | ||
121 | if (!len) | |
122 | return trace_seq_printf(s, " %s=(fault)", name); | |
123 | else | |
124 | return trace_seq_printf(s, " %s=\"%s\"", name, | |
125 | (const char *)get_loc_data(data, ent)); | |
126 | } | |
127 | static const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\""; | |
128 | ||
93ccae7a MH |
129 | /* Data fetch function type */ |
130 | typedef void (*fetch_func_t)(struct pt_regs *, void *, void *); | |
131 | ||
132 | struct fetch_param { | |
133 | fetch_func_t fn; | |
413d37d1 MH |
134 | void *data; |
135 | }; | |
136 | ||
93ccae7a MH |
137 | static __kprobes void call_fetch(struct fetch_param *fprm, |
138 | struct pt_regs *regs, void *dest) | |
413d37d1 | 139 | { |
93ccae7a | 140 | return fprm->fn(regs, fprm->data, dest); |
413d37d1 MH |
141 | } |
142 | ||
e09c8614 | 143 | #define FETCH_FUNC_NAME(method, type) fetch_##method##_##type |
93ccae7a MH |
144 | /* |
145 | * Define macro for basic types - we don't need to define s* types, because | |
146 | * we have to care only about bitwidth at recording time. | |
147 | */ | |
e09c8614 MH |
148 | #define DEFINE_BASIC_FETCH_FUNCS(method) \ |
149 | DEFINE_FETCH_##method(u8) \ | |
150 | DEFINE_FETCH_##method(u16) \ | |
151 | DEFINE_FETCH_##method(u32) \ | |
152 | DEFINE_FETCH_##method(u64) | |
153 | ||
154 | #define CHECK_FETCH_FUNCS(method, fn) \ | |
155 | (((FETCH_FUNC_NAME(method, u8) == fn) || \ | |
156 | (FETCH_FUNC_NAME(method, u16) == fn) || \ | |
157 | (FETCH_FUNC_NAME(method, u32) == fn) || \ | |
158 | (FETCH_FUNC_NAME(method, u64) == fn) || \ | |
159 | (FETCH_FUNC_NAME(method, string) == fn) || \ | |
160 | (FETCH_FUNC_NAME(method, string_size) == fn)) \ | |
161 | && (fn != NULL)) | |
93ccae7a MH |
162 | |
163 | /* Data fetch function templates */ | |
164 | #define DEFINE_FETCH_reg(type) \ | |
165 | static __kprobes void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs, \ | |
e09c8614 | 166 | void *offset, void *dest) \ |
93ccae7a MH |
167 | { \ |
168 | *(type *)dest = (type)regs_get_register(regs, \ | |
169 | (unsigned int)((unsigned long)offset)); \ | |
413d37d1 | 170 | } |
93ccae7a | 171 | DEFINE_BASIC_FETCH_FUNCS(reg) |
e09c8614 MH |
172 | /* No string on the register */ |
173 | #define fetch_reg_string NULL | |
174 | #define fetch_reg_string_size NULL | |
93ccae7a MH |
175 | |
176 | #define DEFINE_FETCH_stack(type) \ | |
177 | static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\ | |
178 | void *offset, void *dest) \ | |
179 | { \ | |
180 | *(type *)dest = (type)regs_get_kernel_stack_nth(regs, \ | |
181 | (unsigned int)((unsigned long)offset)); \ | |
413d37d1 | 182 | } |
93ccae7a | 183 | DEFINE_BASIC_FETCH_FUNCS(stack) |
e09c8614 MH |
184 | /* No string on the stack entry */ |
185 | #define fetch_stack_string NULL | |
186 | #define fetch_stack_string_size NULL | |
413d37d1 | 187 | |
93ccae7a MH |
188 | #define DEFINE_FETCH_retval(type) \ |
189 | static __kprobes void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs,\ | |
190 | void *dummy, void *dest) \ | |
191 | { \ | |
192 | *(type *)dest = (type)regs_return_value(regs); \ | |
413d37d1 | 193 | } |
93ccae7a | 194 | DEFINE_BASIC_FETCH_FUNCS(retval) |
e09c8614 MH |
195 | /* No string on the retval */ |
196 | #define fetch_retval_string NULL | |
197 | #define fetch_retval_string_size NULL | |
93ccae7a MH |
198 | |
199 | #define DEFINE_FETCH_memory(type) \ | |
200 | static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\ | |
201 | void *addr, void *dest) \ | |
202 | { \ | |
203 | type retval; \ | |
204 | if (probe_kernel_address(addr, retval)) \ | |
205 | *(type *)dest = 0; \ | |
206 | else \ | |
207 | *(type *)dest = retval; \ | |
413d37d1 | 208 | } |
93ccae7a | 209 | DEFINE_BASIC_FETCH_FUNCS(memory) |
e09c8614 MH |
210 | /* |
211 | * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max | |
212 | * length and relative data location. | |
213 | */ | |
214 | static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, | |
215 | void *addr, void *dest) | |
216 | { | |
217 | long ret; | |
218 | int maxlen = get_rloc_len(*(u32 *)dest); | |
219 | u8 *dst = get_rloc_data(dest); | |
220 | u8 *src = addr; | |
221 | mm_segment_t old_fs = get_fs(); | |
222 | if (!maxlen) | |
223 | return; | |
224 | /* | |
225 | * Try to get string again, since the string can be changed while | |
226 | * probing. | |
227 | */ | |
228 | set_fs(KERNEL_DS); | |
229 | pagefault_disable(); | |
230 | do | |
231 | ret = __copy_from_user_inatomic(dst++, src++, 1); | |
232 | while (dst[-1] && ret == 0 && src - (u8 *)addr < maxlen); | |
233 | dst[-1] = '\0'; | |
234 | pagefault_enable(); | |
235 | set_fs(old_fs); | |
236 | ||
237 | if (ret < 0) { /* Failed to fetch string */ | |
238 | ((u8 *)get_rloc_data(dest))[0] = '\0'; | |
239 | *(u32 *)dest = make_data_rloc(0, get_rloc_offs(*(u32 *)dest)); | |
240 | } else | |
241 | *(u32 *)dest = make_data_rloc(src - (u8 *)addr, | |
242 | get_rloc_offs(*(u32 *)dest)); | |
243 | } | |
244 | /* Return the length of string -- including null terminal byte */ | |
245 | static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs, | |
246 | void *addr, void *dest) | |
247 | { | |
248 | int ret, len = 0; | |
249 | u8 c; | |
250 | mm_segment_t old_fs = get_fs(); | |
251 | ||
252 | set_fs(KERNEL_DS); | |
253 | pagefault_disable(); | |
254 | do { | |
255 | ret = __copy_from_user_inatomic(&c, (u8 *)addr + len, 1); | |
256 | len++; | |
257 | } while (c && ret == 0 && len < MAX_STRING_SIZE); | |
258 | pagefault_enable(); | |
259 | set_fs(old_fs); | |
260 | ||
261 | if (ret < 0) /* Failed to check the length */ | |
262 | *(u32 *)dest = 0; | |
263 | else | |
264 | *(u32 *)dest = len; | |
265 | } | |
413d37d1 MH |
266 | |
267 | /* Memory fetching by symbol */ | |
268 | struct symbol_cache { | |
269 | char *symbol; | |
270 | long offset; | |
271 | unsigned long addr; | |
272 | }; | |
273 | ||
274 | static unsigned long update_symbol_cache(struct symbol_cache *sc) | |
275 | { | |
276 | sc->addr = (unsigned long)kallsyms_lookup_name(sc->symbol); | |
277 | if (sc->addr) | |
278 | sc->addr += sc->offset; | |
279 | return sc->addr; | |
280 | } | |
281 | ||
282 | static void free_symbol_cache(struct symbol_cache *sc) | |
283 | { | |
284 | kfree(sc->symbol); | |
285 | kfree(sc); | |
286 | } | |
287 | ||
288 | static struct symbol_cache *alloc_symbol_cache(const char *sym, long offset) | |
289 | { | |
290 | struct symbol_cache *sc; | |
291 | ||
292 | if (!sym || strlen(sym) == 0) | |
293 | return NULL; | |
294 | sc = kzalloc(sizeof(struct symbol_cache), GFP_KERNEL); | |
295 | if (!sc) | |
296 | return NULL; | |
297 | ||
298 | sc->symbol = kstrdup(sym, GFP_KERNEL); | |
299 | if (!sc->symbol) { | |
300 | kfree(sc); | |
301 | return NULL; | |
302 | } | |
303 | sc->offset = offset; | |
304 | ||
305 | update_symbol_cache(sc); | |
306 | return sc; | |
307 | } | |
308 | ||
93ccae7a MH |
309 | #define DEFINE_FETCH_symbol(type) \ |
310 | static __kprobes void FETCH_FUNC_NAME(symbol, type)(struct pt_regs *regs,\ | |
311 | void *data, void *dest) \ | |
312 | { \ | |
313 | struct symbol_cache *sc = data; \ | |
314 | if (sc->addr) \ | |
315 | fetch_memory_##type(regs, (void *)sc->addr, dest); \ | |
316 | else \ | |
317 | *(type *)dest = 0; \ | |
413d37d1 | 318 | } |
93ccae7a | 319 | DEFINE_BASIC_FETCH_FUNCS(symbol) |
e09c8614 MH |
320 | DEFINE_FETCH_symbol(string) |
321 | DEFINE_FETCH_symbol(string_size) | |
413d37d1 | 322 | |
93ccae7a MH |
323 | /* Dereference memory access function */ |
324 | struct deref_fetch_param { | |
325 | struct fetch_param orig; | |
413d37d1 MH |
326 | long offset; |
327 | }; | |
328 | ||
93ccae7a MH |
329 | #define DEFINE_FETCH_deref(type) \ |
330 | static __kprobes void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs,\ | |
331 | void *data, void *dest) \ | |
332 | { \ | |
333 | struct deref_fetch_param *dprm = data; \ | |
334 | unsigned long addr; \ | |
335 | call_fetch(&dprm->orig, regs, &addr); \ | |
336 | if (addr) { \ | |
337 | addr += dprm->offset; \ | |
338 | fetch_memory_##type(regs, (void *)addr, dest); \ | |
339 | } else \ | |
340 | *(type *)dest = 0; \ | |
413d37d1 | 341 | } |
93ccae7a | 342 | DEFINE_BASIC_FETCH_FUNCS(deref) |
e09c8614 MH |
343 | DEFINE_FETCH_deref(string) |
344 | DEFINE_FETCH_deref(string_size) | |
413d37d1 | 345 | |
7f6878a3 MH |
346 | static __kprobes void update_deref_fetch_param(struct deref_fetch_param *data) |
347 | { | |
348 | if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) | |
349 | update_deref_fetch_param(data->orig.data); | |
350 | else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) | |
351 | update_symbol_cache(data->orig.data); | |
352 | } | |
353 | ||
93ccae7a | 354 | static __kprobes void free_deref_fetch_param(struct deref_fetch_param *data) |
413d37d1 | 355 | { |
e09c8614 | 356 | if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) |
93ccae7a | 357 | free_deref_fetch_param(data->orig.data); |
e09c8614 | 358 | else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) |
413d37d1 MH |
359 | free_symbol_cache(data->orig.data); |
360 | kfree(data); | |
361 | } | |
362 | ||
1ff511e3 MH |
363 | /* Bitfield fetch function */ |
364 | struct bitfield_fetch_param { | |
365 | struct fetch_param orig; | |
366 | unsigned char hi_shift; | |
367 | unsigned char low_shift; | |
368 | }; | |
369 | ||
370 | #define DEFINE_FETCH_bitfield(type) \ | |
371 | static __kprobes void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs,\ | |
372 | void *data, void *dest) \ | |
373 | { \ | |
374 | struct bitfield_fetch_param *bprm = data; \ | |
375 | type buf = 0; \ | |
376 | call_fetch(&bprm->orig, regs, &buf); \ | |
377 | if (buf) { \ | |
378 | buf <<= bprm->hi_shift; \ | |
379 | buf >>= bprm->low_shift; \ | |
380 | } \ | |
381 | *(type *)dest = buf; \ | |
382 | } | |
383 | DEFINE_BASIC_FETCH_FUNCS(bitfield) | |
384 | #define fetch_bitfield_string NULL | |
385 | #define fetch_bitfield_string_size NULL | |
386 | ||
7f6878a3 MH |
387 | static __kprobes void |
388 | update_bitfield_fetch_param(struct bitfield_fetch_param *data) | |
389 | { | |
390 | /* | |
391 | * Don't check the bitfield itself, because this must be the | |
392 | * last fetch function. | |
393 | */ | |
394 | if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) | |
395 | update_deref_fetch_param(data->orig.data); | |
396 | else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) | |
397 | update_symbol_cache(data->orig.data); | |
398 | } | |
399 | ||
1ff511e3 MH |
400 | static __kprobes void |
401 | free_bitfield_fetch_param(struct bitfield_fetch_param *data) | |
402 | { | |
403 | /* | |
404 | * Don't check the bitfield itself, because this must be the | |
405 | * last fetch function. | |
406 | */ | |
407 | if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) | |
408 | free_deref_fetch_param(data->orig.data); | |
409 | else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) | |
410 | free_symbol_cache(data->orig.data); | |
411 | kfree(data); | |
412 | } | |
7f6878a3 | 413 | |
93ccae7a MH |
414 | /* Default (unsigned long) fetch type */ |
415 | #define __DEFAULT_FETCH_TYPE(t) u##t | |
416 | #define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t) | |
417 | #define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG) | |
418 | #define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE) | |
419 | ||
e09c8614 MH |
420 | /* Fetch types */ |
421 | enum { | |
422 | FETCH_MTD_reg = 0, | |
423 | FETCH_MTD_stack, | |
424 | FETCH_MTD_retval, | |
425 | FETCH_MTD_memory, | |
426 | FETCH_MTD_symbol, | |
427 | FETCH_MTD_deref, | |
1ff511e3 | 428 | FETCH_MTD_bitfield, |
e09c8614 MH |
429 | FETCH_MTD_END, |
430 | }; | |
431 | ||
432 | #define ASSIGN_FETCH_FUNC(method, type) \ | |
433 | [FETCH_MTD_##method] = FETCH_FUNC_NAME(method, type) | |
434 | ||
435 | #define __ASSIGN_FETCH_TYPE(_name, ptype, ftype, _size, sign, _fmttype) \ | |
436 | {.name = _name, \ | |
437 | .size = _size, \ | |
438 | .is_signed = sign, \ | |
439 | .print = PRINT_TYPE_FUNC_NAME(ptype), \ | |
440 | .fmt = PRINT_TYPE_FMT_NAME(ptype), \ | |
441 | .fmttype = _fmttype, \ | |
442 | .fetch = { \ | |
443 | ASSIGN_FETCH_FUNC(reg, ftype), \ | |
444 | ASSIGN_FETCH_FUNC(stack, ftype), \ | |
445 | ASSIGN_FETCH_FUNC(retval, ftype), \ | |
446 | ASSIGN_FETCH_FUNC(memory, ftype), \ | |
447 | ASSIGN_FETCH_FUNC(symbol, ftype), \ | |
448 | ASSIGN_FETCH_FUNC(deref, ftype), \ | |
1ff511e3 | 449 | ASSIGN_FETCH_FUNC(bitfield, ftype), \ |
e09c8614 | 450 | } \ |
93ccae7a MH |
451 | } |
452 | ||
e09c8614 MH |
453 | #define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \ |
454 | __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype) | |
455 | ||
456 | #define FETCH_TYPE_STRING 0 | |
457 | #define FETCH_TYPE_STRSIZE 1 | |
458 | ||
93ccae7a MH |
459 | /* Fetch type information table */ |
460 | static const struct fetch_type { | |
461 | const char *name; /* Name of type */ | |
462 | size_t size; /* Byte size of type */ | |
463 | int is_signed; /* Signed flag */ | |
464 | print_type_func_t print; /* Print functions */ | |
465 | const char *fmt; /* Fromat string */ | |
e09c8614 | 466 | const char *fmttype; /* Name in format file */ |
93ccae7a | 467 | /* Fetch functions */ |
e09c8614 | 468 | fetch_func_t fetch[FETCH_MTD_END]; |
93ccae7a | 469 | } fetch_type_table[] = { |
e09c8614 MH |
470 | /* Special types */ |
471 | [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string, | |
472 | sizeof(u32), 1, "__data_loc char[]"), | |
473 | [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32, | |
474 | string_size, sizeof(u32), 0, "u32"), | |
475 | /* Basic types */ | |
93ccae7a MH |
476 | ASSIGN_FETCH_TYPE(u8, u8, 0), |
477 | ASSIGN_FETCH_TYPE(u16, u16, 0), | |
478 | ASSIGN_FETCH_TYPE(u32, u32, 0), | |
479 | ASSIGN_FETCH_TYPE(u64, u64, 0), | |
480 | ASSIGN_FETCH_TYPE(s8, u8, 1), | |
481 | ASSIGN_FETCH_TYPE(s16, u16, 1), | |
482 | ASSIGN_FETCH_TYPE(s32, u32, 1), | |
483 | ASSIGN_FETCH_TYPE(s64, u64, 1), | |
484 | }; | |
485 | ||
486 | static const struct fetch_type *find_fetch_type(const char *type) | |
487 | { | |
488 | int i; | |
489 | ||
490 | if (!type) | |
491 | type = DEFAULT_FETCH_TYPE_STR; | |
492 | ||
1ff511e3 MH |
493 | /* Special case: bitfield */ |
494 | if (*type == 'b') { | |
495 | unsigned long bs; | |
496 | type = strchr(type, '/'); | |
497 | if (!type) | |
498 | goto fail; | |
499 | type++; | |
500 | if (strict_strtoul(type, 0, &bs)) | |
501 | goto fail; | |
502 | switch (bs) { | |
503 | case 8: | |
504 | return find_fetch_type("u8"); | |
505 | case 16: | |
506 | return find_fetch_type("u16"); | |
507 | case 32: | |
508 | return find_fetch_type("u32"); | |
509 | case 64: | |
510 | return find_fetch_type("u64"); | |
511 | default: | |
512 | goto fail; | |
513 | } | |
514 | } | |
515 | ||
93ccae7a MH |
516 | for (i = 0; i < ARRAY_SIZE(fetch_type_table); i++) |
517 | if (strcmp(type, fetch_type_table[i].name) == 0) | |
518 | return &fetch_type_table[i]; | |
1ff511e3 | 519 | fail: |
93ccae7a MH |
520 | return NULL; |
521 | } | |
522 | ||
523 | /* Special function : only accept unsigned long */ | |
524 | static __kprobes void fetch_stack_address(struct pt_regs *regs, | |
525 | void *dummy, void *dest) | |
526 | { | |
527 | *(unsigned long *)dest = kernel_stack_pointer(regs); | |
528 | } | |
529 | ||
e09c8614 MH |
530 | static fetch_func_t get_fetch_size_function(const struct fetch_type *type, |
531 | fetch_func_t orig_fn) | |
532 | { | |
533 | int i; | |
534 | ||
535 | if (type != &fetch_type_table[FETCH_TYPE_STRING]) | |
536 | return NULL; /* Only string type needs size function */ | |
537 | for (i = 0; i < FETCH_MTD_END; i++) | |
538 | if (type->fetch[i] == orig_fn) | |
539 | return fetch_type_table[FETCH_TYPE_STRSIZE].fetch[i]; | |
540 | ||
541 | WARN_ON(1); /* This should not happen */ | |
542 | return NULL; | |
543 | } | |
544 | ||
413d37d1 | 545 | /** |
77b44d1b | 546 | * Kprobe event core functions |
413d37d1 MH |
547 | */ |
548 | ||
eca0d916 | 549 | struct probe_arg { |
93ccae7a | 550 | struct fetch_param fetch; |
e09c8614 | 551 | struct fetch_param fetch_size; |
93ccae7a MH |
552 | unsigned int offset; /* Offset from argument entry */ |
553 | const char *name; /* Name of this argument */ | |
554 | const char *comm; /* Command of this argument */ | |
555 | const struct fetch_type *type; /* Type of this argument */ | |
eca0d916 MH |
556 | }; |
557 | ||
50d78056 MH |
558 | /* Flags for trace_probe */ |
559 | #define TP_FLAG_TRACE 1 | |
560 | #define TP_FLAG_PROFILE 2 | |
61424318 | 561 | #define TP_FLAG_REGISTERED 4 |
50d78056 | 562 | |
413d37d1 MH |
563 | struct trace_probe { |
564 | struct list_head list; | |
4a846b44 | 565 | struct kretprobe rp; /* Use rp.kp for kprobe use */ |
cd7e7bd5 | 566 | unsigned long nhit; |
50d78056 | 567 | unsigned int flags; /* For TP_FLAG_* */ |
413d37d1 | 568 | const char *symbol; /* symbol name */ |
2239291a | 569 | struct ftrace_event_class class; |
413d37d1 | 570 | struct ftrace_event_call call; |
93ccae7a | 571 | ssize_t size; /* trace entry size */ |
a82378d8 | 572 | unsigned int nr_args; |
eca0d916 | 573 | struct probe_arg args[]; |
413d37d1 MH |
574 | }; |
575 | ||
a82378d8 MH |
576 | #define SIZEOF_TRACE_PROBE(n) \ |
577 | (offsetof(struct trace_probe, args) + \ | |
eca0d916 | 578 | (sizeof(struct probe_arg) * (n))) |
a82378d8 | 579 | |
93ccae7a | 580 | |
7143f168 | 581 | static __kprobes int trace_probe_is_return(struct trace_probe *tp) |
413d37d1 | 582 | { |
4a846b44 | 583 | return tp->rp.handler != NULL; |
413d37d1 MH |
584 | } |
585 | ||
7143f168 | 586 | static __kprobes const char *trace_probe_symbol(struct trace_probe *tp) |
413d37d1 MH |
587 | { |
588 | return tp->symbol ? tp->symbol : "unknown"; | |
589 | } | |
590 | ||
61424318 MH |
591 | static __kprobes unsigned long trace_probe_offset(struct trace_probe *tp) |
592 | { | |
593 | return tp->rp.kp.offset; | |
594 | } | |
595 | ||
596 | static __kprobes bool trace_probe_is_enabled(struct trace_probe *tp) | |
597 | { | |
598 | return !!(tp->flags & (TP_FLAG_TRACE | TP_FLAG_PROFILE)); | |
599 | } | |
600 | ||
601 | static __kprobes bool trace_probe_is_registered(struct trace_probe *tp) | |
602 | { | |
603 | return !!(tp->flags & TP_FLAG_REGISTERED); | |
604 | } | |
605 | ||
606 | static __kprobes bool trace_probe_has_gone(struct trace_probe *tp) | |
607 | { | |
608 | return !!(kprobe_gone(&tp->rp.kp)); | |
609 | } | |
610 | ||
611 | static __kprobes bool trace_probe_within_module(struct trace_probe *tp, | |
612 | struct module *mod) | |
613 | { | |
614 | int len = strlen(mod->name); | |
615 | const char *name = trace_probe_symbol(tp); | |
616 | return strncmp(mod->name, name, len) == 0 && name[len] == ':'; | |
617 | } | |
618 | ||
619 | static __kprobes bool trace_probe_is_on_module(struct trace_probe *tp) | |
620 | { | |
621 | return !!strchr(trace_probe_symbol(tp), ':'); | |
622 | } | |
623 | ||
413d37d1 MH |
624 | static int register_probe_event(struct trace_probe *tp); |
625 | static void unregister_probe_event(struct trace_probe *tp); | |
626 | ||
627 | static DEFINE_MUTEX(probe_lock); | |
628 | static LIST_HEAD(probe_list); | |
629 | ||
50d78056 MH |
630 | static int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs); |
631 | static int kretprobe_dispatcher(struct kretprobe_instance *ri, | |
632 | struct pt_regs *regs); | |
633 | ||
da34634f MH |
634 | /* Check the name is good for event/group/fields */ |
635 | static int is_good_name(const char *name) | |
6f3cf440 MH |
636 | { |
637 | if (!isalpha(*name) && *name != '_') | |
638 | return 0; | |
639 | while (*++name != '\0') { | |
640 | if (!isalpha(*name) && !isdigit(*name) && *name != '_') | |
641 | return 0; | |
642 | } | |
643 | return 1; | |
644 | } | |
645 | ||
4a846b44 MH |
646 | /* |
647 | * Allocate new trace_probe and initialize it (including kprobes). | |
648 | */ | |
f52487e9 MH |
649 | static struct trace_probe *alloc_trace_probe(const char *group, |
650 | const char *event, | |
4a846b44 MH |
651 | void *addr, |
652 | const char *symbol, | |
653 | unsigned long offs, | |
3a6b7666 | 654 | int nargs, bool is_return) |
413d37d1 MH |
655 | { |
656 | struct trace_probe *tp; | |
6f3cf440 | 657 | int ret = -ENOMEM; |
413d37d1 | 658 | |
a82378d8 | 659 | tp = kzalloc(SIZEOF_TRACE_PROBE(nargs), GFP_KERNEL); |
413d37d1 | 660 | if (!tp) |
6f3cf440 | 661 | return ERR_PTR(ret); |
413d37d1 MH |
662 | |
663 | if (symbol) { | |
664 | tp->symbol = kstrdup(symbol, GFP_KERNEL); | |
665 | if (!tp->symbol) | |
666 | goto error; | |
4a846b44 MH |
667 | tp->rp.kp.symbol_name = tp->symbol; |
668 | tp->rp.kp.offset = offs; | |
669 | } else | |
670 | tp->rp.kp.addr = addr; | |
671 | ||
672 | if (is_return) | |
50d78056 | 673 | tp->rp.handler = kretprobe_dispatcher; |
4a846b44 | 674 | else |
50d78056 | 675 | tp->rp.kp.pre_handler = kprobe_dispatcher; |
4a846b44 | 676 | |
da34634f | 677 | if (!event || !is_good_name(event)) { |
6f3cf440 | 678 | ret = -EINVAL; |
4263565d | 679 | goto error; |
6f3cf440 MH |
680 | } |
681 | ||
2239291a | 682 | tp->call.class = &tp->class; |
4263565d MH |
683 | tp->call.name = kstrdup(event, GFP_KERNEL); |
684 | if (!tp->call.name) | |
685 | goto error; | |
413d37d1 | 686 | |
da34634f | 687 | if (!group || !is_good_name(group)) { |
6f3cf440 | 688 | ret = -EINVAL; |
f52487e9 | 689 | goto error; |
6f3cf440 MH |
690 | } |
691 | ||
2239291a SR |
692 | tp->class.system = kstrdup(group, GFP_KERNEL); |
693 | if (!tp->class.system) | |
f52487e9 MH |
694 | goto error; |
695 | ||
413d37d1 MH |
696 | INIT_LIST_HEAD(&tp->list); |
697 | return tp; | |
698 | error: | |
f52487e9 | 699 | kfree(tp->call.name); |
413d37d1 MH |
700 | kfree(tp->symbol); |
701 | kfree(tp); | |
6f3cf440 | 702 | return ERR_PTR(ret); |
413d37d1 MH |
703 | } |
704 | ||
7f6878a3 MH |
705 | static void update_probe_arg(struct probe_arg *arg) |
706 | { | |
707 | if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn)) | |
708 | update_bitfield_fetch_param(arg->fetch.data); | |
709 | else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn)) | |
710 | update_deref_fetch_param(arg->fetch.data); | |
711 | else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn)) | |
712 | update_symbol_cache(arg->fetch.data); | |
713 | } | |
714 | ||
eca0d916 MH |
715 | static void free_probe_arg(struct probe_arg *arg) |
716 | { | |
1ff511e3 MH |
717 | if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn)) |
718 | free_bitfield_fetch_param(arg->fetch.data); | |
719 | else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn)) | |
93ccae7a | 720 | free_deref_fetch_param(arg->fetch.data); |
e09c8614 | 721 | else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn)) |
eca0d916 | 722 | free_symbol_cache(arg->fetch.data); |
eca0d916 | 723 | kfree(arg->name); |
93ccae7a | 724 | kfree(arg->comm); |
eca0d916 MH |
725 | } |
726 | ||
413d37d1 MH |
727 | static void free_trace_probe(struct trace_probe *tp) |
728 | { | |
729 | int i; | |
730 | ||
731 | for (i = 0; i < tp->nr_args; i++) | |
eca0d916 | 732 | free_probe_arg(&tp->args[i]); |
413d37d1 | 733 | |
8f082018 | 734 | kfree(tp->call.class->system); |
413d37d1 MH |
735 | kfree(tp->call.name); |
736 | kfree(tp->symbol); | |
737 | kfree(tp); | |
738 | } | |
739 | ||
7143f168 | 740 | static struct trace_probe *find_trace_probe(const char *event, |
dd004c47 | 741 | const char *group) |
413d37d1 MH |
742 | { |
743 | struct trace_probe *tp; | |
744 | ||
745 | list_for_each_entry(tp, &probe_list, list) | |
dd004c47 | 746 | if (strcmp(tp->call.name, event) == 0 && |
8f082018 | 747 | strcmp(tp->call.class->system, group) == 0) |
413d37d1 MH |
748 | return tp; |
749 | return NULL; | |
750 | } | |
751 | ||
1538f888 MH |
752 | /* Enable trace_probe - @flag must be TP_FLAG_TRACE or TP_FLAG_PROFILE */ |
753 | static int enable_trace_probe(struct trace_probe *tp, int flag) | |
754 | { | |
755 | int ret = 0; | |
756 | ||
757 | tp->flags |= flag; | |
61424318 MH |
758 | if (trace_probe_is_enabled(tp) && trace_probe_is_registered(tp) && |
759 | !trace_probe_has_gone(tp)) { | |
1538f888 MH |
760 | if (trace_probe_is_return(tp)) |
761 | ret = enable_kretprobe(&tp->rp); | |
762 | else | |
763 | ret = enable_kprobe(&tp->rp.kp); | |
764 | } | |
765 | ||
766 | return ret; | |
767 | } | |
768 | ||
769 | /* Disable trace_probe - @flag must be TP_FLAG_TRACE or TP_FLAG_PROFILE */ | |
770 | static void disable_trace_probe(struct trace_probe *tp, int flag) | |
771 | { | |
772 | tp->flags &= ~flag; | |
61424318 | 773 | if (!trace_probe_is_enabled(tp) && trace_probe_is_registered(tp)) { |
1538f888 MH |
774 | if (trace_probe_is_return(tp)) |
775 | disable_kretprobe(&tp->rp); | |
776 | else | |
777 | disable_kprobe(&tp->rp.kp); | |
778 | } | |
779 | } | |
780 | ||
61424318 MH |
781 | /* Internal register function - just handle k*probes and flags */ |
782 | static int __register_trace_probe(struct trace_probe *tp) | |
413d37d1 | 783 | { |
7f6878a3 | 784 | int i, ret; |
61424318 MH |
785 | |
786 | if (trace_probe_is_registered(tp)) | |
787 | return -EINVAL; | |
788 | ||
7f6878a3 MH |
789 | for (i = 0; i < tp->nr_args; i++) |
790 | update_probe_arg(&tp->args[i]); | |
791 | ||
61424318 MH |
792 | /* Set/clear disabled flag according to tp->flag */ |
793 | if (trace_probe_is_enabled(tp)) | |
794 | tp->rp.kp.flags &= ~KPROBE_FLAG_DISABLED; | |
795 | else | |
796 | tp->rp.kp.flags |= KPROBE_FLAG_DISABLED; | |
797 | ||
7143f168 | 798 | if (trace_probe_is_return(tp)) |
61424318 | 799 | ret = register_kretprobe(&tp->rp); |
413d37d1 | 800 | else |
61424318 MH |
801 | ret = register_kprobe(&tp->rp.kp); |
802 | ||
803 | if (ret == 0) | |
804 | tp->flags |= TP_FLAG_REGISTERED; | |
805 | else { | |
806 | pr_warning("Could not insert probe at %s+%lu: %d\n", | |
807 | trace_probe_symbol(tp), trace_probe_offset(tp), ret); | |
808 | if (ret == -ENOENT && trace_probe_is_on_module(tp)) { | |
809 | pr_warning("This probe might be able to register after" | |
810 | "target module is loaded. Continue.\n"); | |
811 | ret = 0; | |
812 | } else if (ret == -EILSEQ) { | |
813 | pr_warning("Probing address(0x%p) is not an " | |
814 | "instruction boundary.\n", | |
815 | tp->rp.kp.addr); | |
816 | ret = -EINVAL; | |
817 | } | |
818 | } | |
819 | ||
820 | return ret; | |
821 | } | |
822 | ||
823 | /* Internal unregister function - just handle k*probes and flags */ | |
824 | static void __unregister_trace_probe(struct trace_probe *tp) | |
825 | { | |
826 | if (trace_probe_is_registered(tp)) { | |
827 | if (trace_probe_is_return(tp)) | |
828 | unregister_kretprobe(&tp->rp); | |
829 | else | |
830 | unregister_kprobe(&tp->rp.kp); | |
831 | tp->flags &= ~TP_FLAG_REGISTERED; | |
832 | /* Cleanup kprobe for reuse */ | |
833 | if (tp->rp.kp.symbol_name) | |
834 | tp->rp.kp.addr = NULL; | |
835 | } | |
836 | } | |
837 | ||
838 | /* Unregister a trace_probe and probe_event: call with locking probe_lock */ | |
02ca1521 | 839 | static int unregister_trace_probe(struct trace_probe *tp) |
61424318 | 840 | { |
02ca1521 MH |
841 | /* Enabled event can not be unregistered */ |
842 | if (trace_probe_is_enabled(tp)) | |
843 | return -EBUSY; | |
844 | ||
61424318 | 845 | __unregister_trace_probe(tp); |
413d37d1 | 846 | list_del(&tp->list); |
2d5e067e | 847 | unregister_probe_event(tp); |
02ca1521 MH |
848 | |
849 | return 0; | |
413d37d1 MH |
850 | } |
851 | ||
852 | /* Register a trace_probe and probe_event */ | |
853 | static int register_trace_probe(struct trace_probe *tp) | |
854 | { | |
855 | struct trace_probe *old_tp; | |
856 | int ret; | |
857 | ||
858 | mutex_lock(&probe_lock); | |
859 | ||
61424318 | 860 | /* Delete old (same name) event if exist */ |
7143f168 | 861 | old_tp = find_trace_probe(tp->call.name, tp->call.class->system); |
2d5e067e | 862 | if (old_tp) { |
02ca1521 MH |
863 | ret = unregister_trace_probe(old_tp); |
864 | if (ret < 0) | |
865 | goto end; | |
2d5e067e MH |
866 | free_trace_probe(old_tp); |
867 | } | |
61424318 MH |
868 | |
869 | /* Register new event */ | |
2d5e067e MH |
870 | ret = register_probe_event(tp); |
871 | if (ret) { | |
426d3107 | 872 | pr_warning("Failed to register probe event(%d)\n", ret); |
2d5e067e MH |
873 | goto end; |
874 | } | |
875 | ||
61424318 MH |
876 | /* Register k*probe */ |
877 | ret = __register_trace_probe(tp); | |
878 | if (ret < 0) | |
2d5e067e | 879 | unregister_probe_event(tp); |
61424318 | 880 | else |
2d5e067e | 881 | list_add_tail(&tp->list, &probe_list); |
61424318 | 882 | |
413d37d1 MH |
883 | end: |
884 | mutex_unlock(&probe_lock); | |
885 | return ret; | |
886 | } | |
887 | ||
61424318 MH |
888 | /* Module notifier call back, checking event on the module */ |
889 | static int trace_probe_module_callback(struct notifier_block *nb, | |
890 | unsigned long val, void *data) | |
891 | { | |
892 | struct module *mod = data; | |
893 | struct trace_probe *tp; | |
894 | int ret; | |
895 | ||
896 | if (val != MODULE_STATE_COMING) | |
897 | return NOTIFY_DONE; | |
898 | ||
899 | /* Update probes on coming module */ | |
900 | mutex_lock(&probe_lock); | |
901 | list_for_each_entry(tp, &probe_list, list) { | |
902 | if (trace_probe_within_module(tp, mod)) { | |
02ca1521 | 903 | /* Don't need to check busy - this should have gone. */ |
61424318 MH |
904 | __unregister_trace_probe(tp); |
905 | ret = __register_trace_probe(tp); | |
906 | if (ret) | |
907 | pr_warning("Failed to re-register probe %s on" | |
908 | "%s: %d\n", | |
909 | tp->call.name, mod->name, ret); | |
910 | } | |
911 | } | |
912 | mutex_unlock(&probe_lock); | |
913 | ||
914 | return NOTIFY_DONE; | |
915 | } | |
916 | ||
917 | static struct notifier_block trace_probe_module_nb = { | |
918 | .notifier_call = trace_probe_module_callback, | |
919 | .priority = 1 /* Invoked after kprobe module callback */ | |
920 | }; | |
921 | ||
413d37d1 | 922 | /* Split symbol and offset. */ |
2fba0c88 | 923 | static int split_symbol_offset(char *symbol, unsigned long *offset) |
413d37d1 MH |
924 | { |
925 | char *tmp; | |
926 | int ret; | |
927 | ||
928 | if (!offset) | |
929 | return -EINVAL; | |
930 | ||
931 | tmp = strchr(symbol, '+'); | |
413d37d1 MH |
932 | if (tmp) { |
933 | /* skip sign because strict_strtol doesn't accept '+' */ | |
2fba0c88 | 934 | ret = strict_strtoul(tmp + 1, 0, offset); |
413d37d1 MH |
935 | if (ret) |
936 | return ret; | |
413d37d1 MH |
937 | *tmp = '\0'; |
938 | } else | |
939 | *offset = 0; | |
940 | return 0; | |
941 | } | |
942 | ||
943 | #define PARAM_MAX_ARGS 16 | |
944 | #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) | |
945 | ||
93ccae7a | 946 | static int parse_probe_vars(char *arg, const struct fetch_type *t, |
3a6b7666 | 947 | struct fetch_param *f, bool is_return) |
413d37d1 MH |
948 | { |
949 | int ret = 0; | |
950 | unsigned long param; | |
413d37d1 | 951 | |
2e06ff63 | 952 | if (strcmp(arg, "retval") == 0) { |
93ccae7a | 953 | if (is_return) |
e09c8614 | 954 | f->fn = t->fetch[FETCH_MTD_retval]; |
93ccae7a | 955 | else |
413d37d1 | 956 | ret = -EINVAL; |
2e06ff63 MH |
957 | } else if (strncmp(arg, "stack", 5) == 0) { |
958 | if (arg[5] == '\0') { | |
93ccae7a MH |
959 | if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR) == 0) |
960 | f->fn = fetch_stack_address; | |
961 | else | |
962 | ret = -EINVAL; | |
2e06ff63 MH |
963 | } else if (isdigit(arg[5])) { |
964 | ret = strict_strtoul(arg + 5, 10, ¶m); | |
413d37d1 MH |
965 | if (ret || param > PARAM_MAX_STACK) |
966 | ret = -EINVAL; | |
967 | else { | |
e09c8614 | 968 | f->fn = t->fetch[FETCH_MTD_stack]; |
93ccae7a | 969 | f->data = (void *)param; |
413d37d1 | 970 | } |
2e06ff63 MH |
971 | } else |
972 | ret = -EINVAL; | |
2e06ff63 | 973 | } else |
405b2651 | 974 | ret = -EINVAL; |
405b2651 MH |
975 | return ret; |
976 | } | |
977 | ||
ba8665d7 | 978 | /* Recursive argument parser */ |
93ccae7a | 979 | static int __parse_probe_arg(char *arg, const struct fetch_type *t, |
3a6b7666 | 980 | struct fetch_param *f, bool is_return) |
405b2651 MH |
981 | { |
982 | int ret = 0; | |
983 | unsigned long param; | |
984 | long offset; | |
985 | char *tmp; | |
986 | ||
987 | switch (arg[0]) { | |
988 | case '$': | |
93ccae7a | 989 | ret = parse_probe_vars(arg + 1, t, f, is_return); |
405b2651 MH |
990 | break; |
991 | case '%': /* named register */ | |
992 | ret = regs_query_register_offset(arg + 1); | |
993 | if (ret >= 0) { | |
e09c8614 | 994 | f->fn = t->fetch[FETCH_MTD_reg]; |
93ccae7a | 995 | f->data = (void *)(unsigned long)ret; |
405b2651 MH |
996 | ret = 0; |
997 | } | |
998 | break; | |
413d37d1 MH |
999 | case '@': /* memory or symbol */ |
1000 | if (isdigit(arg[1])) { | |
1001 | ret = strict_strtoul(arg + 1, 0, ¶m); | |
1002 | if (ret) | |
1003 | break; | |
e09c8614 | 1004 | f->fn = t->fetch[FETCH_MTD_memory]; |
93ccae7a | 1005 | f->data = (void *)param; |
413d37d1 MH |
1006 | } else { |
1007 | ret = split_symbol_offset(arg + 1, &offset); | |
1008 | if (ret) | |
1009 | break; | |
93ccae7a MH |
1010 | f->data = alloc_symbol_cache(arg + 1, offset); |
1011 | if (f->data) | |
e09c8614 | 1012 | f->fn = t->fetch[FETCH_MTD_symbol]; |
413d37d1 MH |
1013 | } |
1014 | break; | |
93ccae7a | 1015 | case '+': /* deref memory */ |
76022db3 | 1016 | arg++; /* Skip '+', because strict_strtol() rejects it. */ |
413d37d1 MH |
1017 | case '-': |
1018 | tmp = strchr(arg, '('); | |
93ccae7a | 1019 | if (!tmp) |
413d37d1 | 1020 | break; |
413d37d1 | 1021 | *tmp = '\0'; |
76022db3 | 1022 | ret = strict_strtol(arg, 0, &offset); |
413d37d1 MH |
1023 | if (ret) |
1024 | break; | |
413d37d1 MH |
1025 | arg = tmp + 1; |
1026 | tmp = strrchr(arg, ')'); | |
1027 | if (tmp) { | |
93ccae7a MH |
1028 | struct deref_fetch_param *dprm; |
1029 | const struct fetch_type *t2 = find_fetch_type(NULL); | |
413d37d1 | 1030 | *tmp = '\0'; |
93ccae7a MH |
1031 | dprm = kzalloc(sizeof(struct deref_fetch_param), |
1032 | GFP_KERNEL); | |
1033 | if (!dprm) | |
413d37d1 | 1034 | return -ENOMEM; |
93ccae7a MH |
1035 | dprm->offset = offset; |
1036 | ret = __parse_probe_arg(arg, t2, &dprm->orig, | |
1037 | is_return); | |
413d37d1 | 1038 | if (ret) |
93ccae7a | 1039 | kfree(dprm); |
413d37d1 | 1040 | else { |
e09c8614 | 1041 | f->fn = t->fetch[FETCH_MTD_deref]; |
93ccae7a | 1042 | f->data = (void *)dprm; |
413d37d1 | 1043 | } |
93ccae7a | 1044 | } |
413d37d1 | 1045 | break; |
413d37d1 | 1046 | } |
e09c8614 MH |
1047 | if (!ret && !f->fn) { /* Parsed, but do not find fetch method */ |
1048 | pr_info("%s type has no corresponding fetch method.\n", | |
1049 | t->name); | |
93ccae7a | 1050 | ret = -EINVAL; |
e09c8614 | 1051 | } |
413d37d1 MH |
1052 | return ret; |
1053 | } | |
1054 | ||
1ff511e3 MH |
1055 | #define BYTES_TO_BITS(nb) ((BITS_PER_LONG * (nb)) / sizeof(long)) |
1056 | ||
1057 | /* Bitfield type needs to be parsed into a fetch function */ | |
1058 | static int __parse_bitfield_probe_arg(const char *bf, | |
1059 | const struct fetch_type *t, | |
1060 | struct fetch_param *f) | |
1061 | { | |
1062 | struct bitfield_fetch_param *bprm; | |
1063 | unsigned long bw, bo; | |
1064 | char *tail; | |
1065 | ||
1066 | if (*bf != 'b') | |
1067 | return 0; | |
1068 | ||
1069 | bprm = kzalloc(sizeof(*bprm), GFP_KERNEL); | |
1070 | if (!bprm) | |
1071 | return -ENOMEM; | |
1072 | bprm->orig = *f; | |
1073 | f->fn = t->fetch[FETCH_MTD_bitfield]; | |
1074 | f->data = (void *)bprm; | |
1075 | ||
1076 | bw = simple_strtoul(bf + 1, &tail, 0); /* Use simple one */ | |
1077 | if (bw == 0 || *tail != '@') | |
1078 | return -EINVAL; | |
1079 | ||
1080 | bf = tail + 1; | |
1081 | bo = simple_strtoul(bf, &tail, 0); | |
1082 | if (tail == bf || *tail != '/') | |
1083 | return -EINVAL; | |
1084 | ||
1085 | bprm->hi_shift = BYTES_TO_BITS(t->size) - (bw + bo); | |
1086 | bprm->low_shift = bprm->hi_shift + bo; | |
1087 | return (BYTES_TO_BITS(t->size) < (bw + bo)) ? -EINVAL : 0; | |
1088 | } | |
1089 | ||
ba8665d7 | 1090 | /* String length checking wrapper */ |
93ccae7a | 1091 | static int parse_probe_arg(char *arg, struct trace_probe *tp, |
3a6b7666 | 1092 | struct probe_arg *parg, bool is_return) |
ba8665d7 | 1093 | { |
93ccae7a | 1094 | const char *t; |
e09c8614 | 1095 | int ret; |
93ccae7a | 1096 | |
ba8665d7 MH |
1097 | if (strlen(arg) > MAX_ARGSTR_LEN) { |
1098 | pr_info("Argument is too long.: %s\n", arg); | |
1099 | return -ENOSPC; | |
1100 | } | |
93ccae7a MH |
1101 | parg->comm = kstrdup(arg, GFP_KERNEL); |
1102 | if (!parg->comm) { | |
1103 | pr_info("Failed to allocate memory for command '%s'.\n", arg); | |
1104 | return -ENOMEM; | |
1105 | } | |
1106 | t = strchr(parg->comm, ':'); | |
1107 | if (t) { | |
1108 | arg[t - parg->comm] = '\0'; | |
1109 | t++; | |
1110 | } | |
1111 | parg->type = find_fetch_type(t); | |
1112 | if (!parg->type) { | |
1113 | pr_info("Unsupported type: %s\n", t); | |
1114 | return -EINVAL; | |
1115 | } | |
1116 | parg->offset = tp->size; | |
1117 | tp->size += parg->type->size; | |
e09c8614 | 1118 | ret = __parse_probe_arg(arg, parg->type, &parg->fetch, is_return); |
0de4b34d | 1119 | if (ret >= 0 && t != NULL) |
1ff511e3 | 1120 | ret = __parse_bitfield_probe_arg(t, parg->type, &parg->fetch); |
e09c8614 MH |
1121 | if (ret >= 0) { |
1122 | parg->fetch_size.fn = get_fetch_size_function(parg->type, | |
1123 | parg->fetch.fn); | |
1124 | parg->fetch_size.data = parg->fetch.data; | |
1125 | } | |
1126 | return ret; | |
ba8665d7 MH |
1127 | } |
1128 | ||
a703d946 MH |
1129 | /* Return 1 if name is reserved or already used by another argument */ |
1130 | static int conflict_field_name(const char *name, | |
1131 | struct probe_arg *args, int narg) | |
1132 | { | |
1133 | int i; | |
1134 | for (i = 0; i < ARRAY_SIZE(reserved_field_names); i++) | |
1135 | if (strcmp(reserved_field_names[i], name) == 0) | |
1136 | return 1; | |
1137 | for (i = 0; i < narg; i++) | |
1138 | if (strcmp(args[i].name, name) == 0) | |
1139 | return 1; | |
1140 | return 0; | |
1141 | } | |
1142 | ||
413d37d1 MH |
1143 | static int create_trace_probe(int argc, char **argv) |
1144 | { | |
1145 | /* | |
1146 | * Argument syntax: | |
61424318 MH |
1147 | * - Add kprobe: p[:[GRP/]EVENT] [MOD:]KSYM[+OFFS]|KADDR [FETCHARGS] |
1148 | * - Add kretprobe: r[:[GRP/]EVENT] [MOD:]KSYM[+0] [FETCHARGS] | |
413d37d1 | 1149 | * Fetch args: |
2e06ff63 MH |
1150 | * $retval : fetch return value |
1151 | * $stack : fetch stack address | |
1152 | * $stackN : fetch Nth of stack (N:0-) | |
413d37d1 MH |
1153 | * @ADDR : fetch memory at ADDR (ADDR should be in kernel) |
1154 | * @SYM[+|-offs] : fetch memory at SYM +|- offs (SYM is a data symbol) | |
1155 | * %REG : fetch register REG | |
93ccae7a | 1156 | * Dereferencing memory fetch: |
413d37d1 | 1157 | * +|-offs(ARG) : fetch memory at ARG +|- offs address. |
eca0d916 MH |
1158 | * Alias name of args: |
1159 | * NAME=FETCHARG : set NAME as alias of FETCHARG. | |
93ccae7a MH |
1160 | * Type of args: |
1161 | * FETCHARG:TYPE : use TYPE instead of unsigned long. | |
413d37d1 MH |
1162 | */ |
1163 | struct trace_probe *tp; | |
413d37d1 | 1164 | int i, ret = 0; |
3a6b7666 | 1165 | bool is_return = false, is_delete = false; |
93ccae7a | 1166 | char *symbol = NULL, *event = NULL, *group = NULL; |
da34634f | 1167 | char *arg; |
2fba0c88 | 1168 | unsigned long offset = 0; |
413d37d1 | 1169 | void *addr = NULL; |
4a846b44 | 1170 | char buf[MAX_EVENT_NAME_LEN]; |
413d37d1 | 1171 | |
a7c312be | 1172 | /* argc must be >= 1 */ |
413d37d1 | 1173 | if (argv[0][0] == 'p') |
3a6b7666 | 1174 | is_return = false; |
413d37d1 | 1175 | else if (argv[0][0] == 'r') |
3a6b7666 | 1176 | is_return = true; |
a7c312be | 1177 | else if (argv[0][0] == '-') |
3a6b7666 | 1178 | is_delete = true; |
e63cc239 | 1179 | else { |
a7c312be MH |
1180 | pr_info("Probe definition must be started with 'p', 'r' or" |
1181 | " '-'.\n"); | |
413d37d1 | 1182 | return -EINVAL; |
e63cc239 | 1183 | } |
413d37d1 MH |
1184 | |
1185 | if (argv[0][1] == ':') { | |
1186 | event = &argv[0][2]; | |
f52487e9 MH |
1187 | if (strchr(event, '/')) { |
1188 | group = event; | |
1189 | event = strchr(group, '/') + 1; | |
1190 | event[-1] = '\0'; | |
1191 | if (strlen(group) == 0) { | |
a5efd925 | 1192 | pr_info("Group name is not specified\n"); |
f52487e9 MH |
1193 | return -EINVAL; |
1194 | } | |
1195 | } | |
413d37d1 | 1196 | if (strlen(event) == 0) { |
a5efd925 | 1197 | pr_info("Event name is not specified\n"); |
413d37d1 MH |
1198 | return -EINVAL; |
1199 | } | |
1200 | } | |
a7c312be MH |
1201 | if (!group) |
1202 | group = KPROBE_EVENT_SYSTEM; | |
413d37d1 | 1203 | |
a7c312be MH |
1204 | if (is_delete) { |
1205 | if (!event) { | |
1206 | pr_info("Delete command needs an event name.\n"); | |
1207 | return -EINVAL; | |
1208 | } | |
9da79ab8 | 1209 | mutex_lock(&probe_lock); |
7143f168 | 1210 | tp = find_trace_probe(event, group); |
a7c312be | 1211 | if (!tp) { |
9da79ab8 | 1212 | mutex_unlock(&probe_lock); |
a7c312be MH |
1213 | pr_info("Event %s/%s doesn't exist.\n", group, event); |
1214 | return -ENOENT; | |
1215 | } | |
1216 | /* delete an event */ | |
02ca1521 MH |
1217 | ret = unregister_trace_probe(tp); |
1218 | if (ret == 0) | |
1219 | free_trace_probe(tp); | |
9da79ab8 | 1220 | mutex_unlock(&probe_lock); |
02ca1521 | 1221 | return ret; |
a7c312be MH |
1222 | } |
1223 | ||
1224 | if (argc < 2) { | |
1225 | pr_info("Probe point is not specified.\n"); | |
1226 | return -EINVAL; | |
1227 | } | |
413d37d1 | 1228 | if (isdigit(argv[1][0])) { |
e63cc239 MH |
1229 | if (is_return) { |
1230 | pr_info("Return probe point must be a symbol.\n"); | |
413d37d1 | 1231 | return -EINVAL; |
e63cc239 | 1232 | } |
413d37d1 | 1233 | /* an address specified */ |
a9bb18f3 | 1234 | ret = strict_strtoul(&argv[1][0], 0, (unsigned long *)&addr); |
e63cc239 MH |
1235 | if (ret) { |
1236 | pr_info("Failed to parse address.\n"); | |
413d37d1 | 1237 | return ret; |
e63cc239 | 1238 | } |
413d37d1 MH |
1239 | } else { |
1240 | /* a symbol specified */ | |
1241 | symbol = argv[1]; | |
1242 | /* TODO: support .init module functions */ | |
1243 | ret = split_symbol_offset(symbol, &offset); | |
e63cc239 MH |
1244 | if (ret) { |
1245 | pr_info("Failed to parse symbol.\n"); | |
413d37d1 | 1246 | return ret; |
e63cc239 MH |
1247 | } |
1248 | if (offset && is_return) { | |
1249 | pr_info("Return probe must be used without offset.\n"); | |
413d37d1 | 1250 | return -EINVAL; |
e63cc239 | 1251 | } |
413d37d1 | 1252 | } |
a82378d8 | 1253 | argc -= 2; argv += 2; |
413d37d1 MH |
1254 | |
1255 | /* setup a probe */ | |
4263565d MH |
1256 | if (!event) { |
1257 | /* Make a new event name */ | |
4263565d | 1258 | if (symbol) |
6f3cf440 | 1259 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_%ld", |
4263565d MH |
1260 | is_return ? 'r' : 'p', symbol, offset); |
1261 | else | |
6f3cf440 | 1262 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_0x%p", |
4263565d | 1263 | is_return ? 'r' : 'p', addr); |
4a846b44 MH |
1264 | event = buf; |
1265 | } | |
f52487e9 MH |
1266 | tp = alloc_trace_probe(group, event, addr, symbol, offset, argc, |
1267 | is_return); | |
e63cc239 MH |
1268 | if (IS_ERR(tp)) { |
1269 | pr_info("Failed to allocate trace_probe.(%d)\n", | |
1270 | (int)PTR_ERR(tp)); | |
413d37d1 | 1271 | return PTR_ERR(tp); |
e63cc239 | 1272 | } |
413d37d1 | 1273 | |
413d37d1 | 1274 | /* parse arguments */ |
a82378d8 MH |
1275 | ret = 0; |
1276 | for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { | |
61a52736 MH |
1277 | /* Increment count for freeing args in error case */ |
1278 | tp->nr_args++; | |
1279 | ||
eca0d916 MH |
1280 | /* Parse argument name */ |
1281 | arg = strchr(argv[i], '='); | |
aba91595 | 1282 | if (arg) { |
eca0d916 | 1283 | *arg++ = '\0'; |
aba91595 MH |
1284 | tp->args[i].name = kstrdup(argv[i], GFP_KERNEL); |
1285 | } else { | |
eca0d916 | 1286 | arg = argv[i]; |
aba91595 MH |
1287 | /* If argument name is omitted, set "argN" */ |
1288 | snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1); | |
1289 | tp->args[i].name = kstrdup(buf, GFP_KERNEL); | |
1290 | } | |
a703d946 | 1291 | |
ba8665d7 | 1292 | if (!tp->args[i].name) { |
aba91595 | 1293 | pr_info("Failed to allocate argument[%d] name.\n", i); |
ba8665d7 | 1294 | ret = -ENOMEM; |
413d37d1 MH |
1295 | goto error; |
1296 | } | |
da34634f MH |
1297 | |
1298 | if (!is_good_name(tp->args[i].name)) { | |
1299 | pr_info("Invalid argument[%d] name: %s\n", | |
1300 | i, tp->args[i].name); | |
1301 | ret = -EINVAL; | |
1302 | goto error; | |
1303 | } | |
93ccae7a MH |
1304 | |
1305 | if (conflict_field_name(tp->args[i].name, tp->args, i)) { | |
aba91595 | 1306 | pr_info("Argument[%d] name '%s' conflicts with " |
93ccae7a MH |
1307 | "another field.\n", i, argv[i]); |
1308 | ret = -EINVAL; | |
1309 | goto error; | |
1310 | } | |
ba8665d7 MH |
1311 | |
1312 | /* Parse fetch argument */ | |
93ccae7a | 1313 | ret = parse_probe_arg(arg, tp, &tp->args[i], is_return); |
e63cc239 | 1314 | if (ret) { |
aba91595 | 1315 | pr_info("Parse error at argument[%d]. (%d)\n", i, ret); |
413d37d1 | 1316 | goto error; |
e63cc239 | 1317 | } |
413d37d1 | 1318 | } |
413d37d1 MH |
1319 | |
1320 | ret = register_trace_probe(tp); | |
1321 | if (ret) | |
1322 | goto error; | |
1323 | return 0; | |
1324 | ||
1325 | error: | |
1326 | free_trace_probe(tp); | |
1327 | return ret; | |
1328 | } | |
1329 | ||
02ca1521 | 1330 | static int release_all_trace_probes(void) |
413d37d1 MH |
1331 | { |
1332 | struct trace_probe *tp; | |
02ca1521 | 1333 | int ret = 0; |
413d37d1 MH |
1334 | |
1335 | mutex_lock(&probe_lock); | |
02ca1521 MH |
1336 | /* Ensure no probe is in use. */ |
1337 | list_for_each_entry(tp, &probe_list, list) | |
1338 | if (trace_probe_is_enabled(tp)) { | |
1339 | ret = -EBUSY; | |
1340 | goto end; | |
1341 | } | |
413d37d1 MH |
1342 | /* TODO: Use batch unregistration */ |
1343 | while (!list_empty(&probe_list)) { | |
1344 | tp = list_entry(probe_list.next, struct trace_probe, list); | |
1345 | unregister_trace_probe(tp); | |
1346 | free_trace_probe(tp); | |
1347 | } | |
02ca1521 MH |
1348 | |
1349 | end: | |
413d37d1 | 1350 | mutex_unlock(&probe_lock); |
02ca1521 MH |
1351 | |
1352 | return ret; | |
413d37d1 MH |
1353 | } |
1354 | ||
413d37d1 MH |
1355 | /* Probes listing interfaces */ |
1356 | static void *probes_seq_start(struct seq_file *m, loff_t *pos) | |
1357 | { | |
1358 | mutex_lock(&probe_lock); | |
1359 | return seq_list_start(&probe_list, *pos); | |
1360 | } | |
1361 | ||
1362 | static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos) | |
1363 | { | |
1364 | return seq_list_next(v, &probe_list, pos); | |
1365 | } | |
1366 | ||
1367 | static void probes_seq_stop(struct seq_file *m, void *v) | |
1368 | { | |
1369 | mutex_unlock(&probe_lock); | |
1370 | } | |
1371 | ||
1372 | static int probes_seq_show(struct seq_file *m, void *v) | |
1373 | { | |
1374 | struct trace_probe *tp = v; | |
93ccae7a | 1375 | int i; |
413d37d1 | 1376 | |
7143f168 | 1377 | seq_printf(m, "%c", trace_probe_is_return(tp) ? 'r' : 'p'); |
8f082018 | 1378 | seq_printf(m, ":%s/%s", tp->call.class->system, tp->call.name); |
413d37d1 | 1379 | |
52a11f35 LJ |
1380 | if (!tp->symbol) |
1381 | seq_printf(m, " 0x%p", tp->rp.kp.addr); | |
1382 | else if (tp->rp.kp.offset) | |
7143f168 MH |
1383 | seq_printf(m, " %s+%u", trace_probe_symbol(tp), |
1384 | tp->rp.kp.offset); | |
413d37d1 | 1385 | else |
7143f168 | 1386 | seq_printf(m, " %s", trace_probe_symbol(tp)); |
413d37d1 | 1387 | |
93ccae7a MH |
1388 | for (i = 0; i < tp->nr_args; i++) |
1389 | seq_printf(m, " %s=%s", tp->args[i].name, tp->args[i].comm); | |
413d37d1 | 1390 | seq_printf(m, "\n"); |
93ccae7a | 1391 | |
413d37d1 MH |
1392 | return 0; |
1393 | } | |
1394 | ||
1395 | static const struct seq_operations probes_seq_op = { | |
1396 | .start = probes_seq_start, | |
1397 | .next = probes_seq_next, | |
1398 | .stop = probes_seq_stop, | |
1399 | .show = probes_seq_show | |
1400 | }; | |
1401 | ||
1402 | static int probes_open(struct inode *inode, struct file *file) | |
1403 | { | |
02ca1521 MH |
1404 | int ret; |
1405 | ||
1406 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { | |
1407 | ret = release_all_trace_probes(); | |
1408 | if (ret < 0) | |
1409 | return ret; | |
1410 | } | |
413d37d1 MH |
1411 | |
1412 | return seq_open(file, &probes_seq_op); | |
1413 | } | |
1414 | ||
1415 | static int command_trace_probe(const char *buf) | |
1416 | { | |
1417 | char **argv; | |
1418 | int argc = 0, ret = 0; | |
1419 | ||
1420 | argv = argv_split(GFP_KERNEL, buf, &argc); | |
1421 | if (!argv) | |
1422 | return -ENOMEM; | |
1423 | ||
1424 | if (argc) | |
1425 | ret = create_trace_probe(argc, argv); | |
1426 | ||
1427 | argv_free(argv); | |
1428 | return ret; | |
1429 | } | |
1430 | ||
e3745369 | 1431 | #define WRITE_BUFSIZE 4096 |
413d37d1 MH |
1432 | |
1433 | static ssize_t probes_write(struct file *file, const char __user *buffer, | |
1434 | size_t count, loff_t *ppos) | |
1435 | { | |
1436 | char *kbuf, *tmp; | |
1437 | int ret; | |
1438 | size_t done; | |
1439 | size_t size; | |
1440 | ||
1441 | kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL); | |
1442 | if (!kbuf) | |
1443 | return -ENOMEM; | |
1444 | ||
1445 | ret = done = 0; | |
1446 | while (done < count) { | |
1447 | size = count - done; | |
1448 | if (size >= WRITE_BUFSIZE) | |
1449 | size = WRITE_BUFSIZE - 1; | |
1450 | if (copy_from_user(kbuf, buffer + done, size)) { | |
1451 | ret = -EFAULT; | |
1452 | goto out; | |
1453 | } | |
1454 | kbuf[size] = '\0'; | |
1455 | tmp = strchr(kbuf, '\n'); | |
1456 | if (tmp) { | |
1457 | *tmp = '\0'; | |
1458 | size = tmp - kbuf + 1; | |
1459 | } else if (done + size < count) { | |
1460 | pr_warning("Line length is too long: " | |
1461 | "Should be less than %d.", WRITE_BUFSIZE); | |
1462 | ret = -EINVAL; | |
1463 | goto out; | |
1464 | } | |
1465 | done += size; | |
1466 | /* Remove comments */ | |
1467 | tmp = strchr(kbuf, '#'); | |
1468 | if (tmp) | |
1469 | *tmp = '\0'; | |
1470 | ||
1471 | ret = command_trace_probe(kbuf); | |
1472 | if (ret) | |
1473 | goto out; | |
1474 | } | |
1475 | ret = done; | |
1476 | out: | |
1477 | kfree(kbuf); | |
1478 | return ret; | |
1479 | } | |
1480 | ||
1481 | static const struct file_operations kprobe_events_ops = { | |
1482 | .owner = THIS_MODULE, | |
1483 | .open = probes_open, | |
1484 | .read = seq_read, | |
1485 | .llseek = seq_lseek, | |
1486 | .release = seq_release, | |
1487 | .write = probes_write, | |
1488 | }; | |
1489 | ||
cd7e7bd5 MH |
1490 | /* Probes profiling interfaces */ |
1491 | static int probes_profile_seq_show(struct seq_file *m, void *v) | |
1492 | { | |
1493 | struct trace_probe *tp = v; | |
1494 | ||
1495 | seq_printf(m, " %-44s %15lu %15lu\n", tp->call.name, tp->nhit, | |
4a846b44 | 1496 | tp->rp.kp.nmissed); |
cd7e7bd5 MH |
1497 | |
1498 | return 0; | |
1499 | } | |
1500 | ||
1501 | static const struct seq_operations profile_seq_op = { | |
1502 | .start = probes_seq_start, | |
1503 | .next = probes_seq_next, | |
1504 | .stop = probes_seq_stop, | |
1505 | .show = probes_profile_seq_show | |
1506 | }; | |
1507 | ||
1508 | static int profile_open(struct inode *inode, struct file *file) | |
1509 | { | |
1510 | return seq_open(file, &profile_seq_op); | |
1511 | } | |
1512 | ||
1513 | static const struct file_operations kprobe_profile_ops = { | |
1514 | .owner = THIS_MODULE, | |
1515 | .open = profile_open, | |
1516 | .read = seq_read, | |
1517 | .llseek = seq_lseek, | |
1518 | .release = seq_release, | |
1519 | }; | |
1520 | ||
e09c8614 MH |
1521 | /* Sum up total data length for dynamic arraies (strings) */ |
1522 | static __kprobes int __get_data_size(struct trace_probe *tp, | |
1523 | struct pt_regs *regs) | |
1524 | { | |
1525 | int i, ret = 0; | |
1526 | u32 len; | |
1527 | ||
1528 | for (i = 0; i < tp->nr_args; i++) | |
1529 | if (unlikely(tp->args[i].fetch_size.fn)) { | |
1530 | call_fetch(&tp->args[i].fetch_size, regs, &len); | |
1531 | ret += len; | |
1532 | } | |
1533 | ||
1534 | return ret; | |
1535 | } | |
1536 | ||
1537 | /* Store the value of each argument */ | |
1538 | static __kprobes void store_trace_args(int ent_size, struct trace_probe *tp, | |
1539 | struct pt_regs *regs, | |
1540 | u8 *data, int maxlen) | |
1541 | { | |
1542 | int i; | |
1543 | u32 end = tp->size; | |
1544 | u32 *dl; /* Data (relative) location */ | |
1545 | ||
1546 | for (i = 0; i < tp->nr_args; i++) { | |
1547 | if (unlikely(tp->args[i].fetch_size.fn)) { | |
1548 | /* | |
1549 | * First, we set the relative location and | |
1550 | * maximum data length to *dl | |
1551 | */ | |
1552 | dl = (u32 *)(data + tp->args[i].offset); | |
1553 | *dl = make_data_rloc(maxlen, end - tp->args[i].offset); | |
1554 | /* Then try to fetch string or dynamic array data */ | |
1555 | call_fetch(&tp->args[i].fetch, regs, dl); | |
1556 | /* Reduce maximum length */ | |
1557 | end += get_rloc_len(*dl); | |
1558 | maxlen -= get_rloc_len(*dl); | |
1559 | /* Trick here, convert data_rloc to data_loc */ | |
1560 | *dl = convert_rloc_to_loc(*dl, | |
1561 | ent_size + tp->args[i].offset); | |
1562 | } else | |
1563 | /* Just fetching data normally */ | |
1564 | call_fetch(&tp->args[i].fetch, regs, | |
1565 | data + tp->args[i].offset); | |
1566 | } | |
1567 | } | |
1568 | ||
413d37d1 | 1569 | /* Kprobe handler */ |
1e12a4a7 | 1570 | static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs) |
413d37d1 | 1571 | { |
4a846b44 | 1572 | struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); |
93ccae7a | 1573 | struct kprobe_trace_entry_head *entry; |
413d37d1 | 1574 | struct ring_buffer_event *event; |
8f8ffe24 | 1575 | struct ring_buffer *buffer; |
e09c8614 | 1576 | int size, dsize, pc; |
413d37d1 | 1577 | unsigned long irq_flags; |
4263565d | 1578 | struct ftrace_event_call *call = &tp->call; |
413d37d1 | 1579 | |
cd7e7bd5 MH |
1580 | tp->nhit++; |
1581 | ||
413d37d1 MH |
1582 | local_save_flags(irq_flags); |
1583 | pc = preempt_count(); | |
1584 | ||
e09c8614 MH |
1585 | dsize = __get_data_size(tp, regs); |
1586 | size = sizeof(*entry) + tp->size + dsize; | |
413d37d1 | 1587 | |
32c0edae SR |
1588 | event = trace_current_buffer_lock_reserve(&buffer, call->event.type, |
1589 | size, irq_flags, pc); | |
413d37d1 | 1590 | if (!event) |
1e12a4a7 | 1591 | return; |
413d37d1 MH |
1592 | |
1593 | entry = ring_buffer_event_data(event); | |
413d37d1 | 1594 | entry->ip = (unsigned long)kp->addr; |
e09c8614 | 1595 | store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); |
413d37d1 | 1596 | |
8f8ffe24 | 1597 | if (!filter_current_check_discard(buffer, call, entry, event)) |
1fd8df2c MH |
1598 | trace_nowake_buffer_unlock_commit_regs(buffer, event, |
1599 | irq_flags, pc, regs); | |
413d37d1 MH |
1600 | } |
1601 | ||
1602 | /* Kretprobe handler */ | |
1e12a4a7 | 1603 | static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri, |
413d37d1 MH |
1604 | struct pt_regs *regs) |
1605 | { | |
1606 | struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); | |
93ccae7a | 1607 | struct kretprobe_trace_entry_head *entry; |
413d37d1 | 1608 | struct ring_buffer_event *event; |
8f8ffe24 | 1609 | struct ring_buffer *buffer; |
e09c8614 | 1610 | int size, pc, dsize; |
413d37d1 | 1611 | unsigned long irq_flags; |
4263565d | 1612 | struct ftrace_event_call *call = &tp->call; |
413d37d1 MH |
1613 | |
1614 | local_save_flags(irq_flags); | |
1615 | pc = preempt_count(); | |
1616 | ||
e09c8614 MH |
1617 | dsize = __get_data_size(tp, regs); |
1618 | size = sizeof(*entry) + tp->size + dsize; | |
413d37d1 | 1619 | |
32c0edae SR |
1620 | event = trace_current_buffer_lock_reserve(&buffer, call->event.type, |
1621 | size, irq_flags, pc); | |
413d37d1 | 1622 | if (!event) |
1e12a4a7 | 1623 | return; |
413d37d1 MH |
1624 | |
1625 | entry = ring_buffer_event_data(event); | |
4a846b44 | 1626 | entry->func = (unsigned long)tp->rp.kp.addr; |
413d37d1 | 1627 | entry->ret_ip = (unsigned long)ri->ret_addr; |
e09c8614 | 1628 | store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); |
413d37d1 | 1629 | |
8f8ffe24 | 1630 | if (!filter_current_check_discard(buffer, call, entry, event)) |
1fd8df2c MH |
1631 | trace_nowake_buffer_unlock_commit_regs(buffer, event, |
1632 | irq_flags, pc, regs); | |
413d37d1 MH |
1633 | } |
1634 | ||
1635 | /* Event entry printers */ | |
1636 | enum print_line_t | |
a9a57763 SR |
1637 | print_kprobe_event(struct trace_iterator *iter, int flags, |
1638 | struct trace_event *event) | |
413d37d1 | 1639 | { |
93ccae7a | 1640 | struct kprobe_trace_entry_head *field; |
413d37d1 | 1641 | struct trace_seq *s = &iter->seq; |
eca0d916 | 1642 | struct trace_probe *tp; |
93ccae7a | 1643 | u8 *data; |
413d37d1 MH |
1644 | int i; |
1645 | ||
93ccae7a | 1646 | field = (struct kprobe_trace_entry_head *)iter->ent; |
80decc70 | 1647 | tp = container_of(event, struct trace_probe, call.event); |
413d37d1 | 1648 | |
6e9f23d1 MH |
1649 | if (!trace_seq_printf(s, "%s: (", tp->call.name)) |
1650 | goto partial; | |
1651 | ||
413d37d1 MH |
1652 | if (!seq_print_ip_sym(s, field->ip, flags | TRACE_ITER_SYM_OFFSET)) |
1653 | goto partial; | |
1654 | ||
6e9f23d1 | 1655 | if (!trace_seq_puts(s, ")")) |
413d37d1 MH |
1656 | goto partial; |
1657 | ||
93ccae7a MH |
1658 | data = (u8 *)&field[1]; |
1659 | for (i = 0; i < tp->nr_args; i++) | |
1660 | if (!tp->args[i].type->print(s, tp->args[i].name, | |
e09c8614 | 1661 | data + tp->args[i].offset, field)) |
413d37d1 MH |
1662 | goto partial; |
1663 | ||
1664 | if (!trace_seq_puts(s, "\n")) | |
1665 | goto partial; | |
1666 | ||
1667 | return TRACE_TYPE_HANDLED; | |
1668 | partial: | |
1669 | return TRACE_TYPE_PARTIAL_LINE; | |
1670 | } | |
1671 | ||
1672 | enum print_line_t | |
a9a57763 SR |
1673 | print_kretprobe_event(struct trace_iterator *iter, int flags, |
1674 | struct trace_event *event) | |
413d37d1 | 1675 | { |
93ccae7a | 1676 | struct kretprobe_trace_entry_head *field; |
413d37d1 | 1677 | struct trace_seq *s = &iter->seq; |
eca0d916 | 1678 | struct trace_probe *tp; |
93ccae7a | 1679 | u8 *data; |
413d37d1 MH |
1680 | int i; |
1681 | ||
93ccae7a | 1682 | field = (struct kretprobe_trace_entry_head *)iter->ent; |
80decc70 | 1683 | tp = container_of(event, struct trace_probe, call.event); |
413d37d1 | 1684 | |
6e9f23d1 MH |
1685 | if (!trace_seq_printf(s, "%s: (", tp->call.name)) |
1686 | goto partial; | |
1687 | ||
413d37d1 MH |
1688 | if (!seq_print_ip_sym(s, field->ret_ip, flags | TRACE_ITER_SYM_OFFSET)) |
1689 | goto partial; | |
1690 | ||
1691 | if (!trace_seq_puts(s, " <- ")) | |
1692 | goto partial; | |
1693 | ||
1694 | if (!seq_print_ip_sym(s, field->func, flags & ~TRACE_ITER_SYM_OFFSET)) | |
1695 | goto partial; | |
1696 | ||
6e9f23d1 | 1697 | if (!trace_seq_puts(s, ")")) |
413d37d1 MH |
1698 | goto partial; |
1699 | ||
93ccae7a MH |
1700 | data = (u8 *)&field[1]; |
1701 | for (i = 0; i < tp->nr_args; i++) | |
1702 | if (!tp->args[i].type->print(s, tp->args[i].name, | |
e09c8614 | 1703 | data + tp->args[i].offset, field)) |
413d37d1 MH |
1704 | goto partial; |
1705 | ||
1706 | if (!trace_seq_puts(s, "\n")) | |
1707 | goto partial; | |
1708 | ||
1709 | return TRACE_TYPE_HANDLED; | |
1710 | partial: | |
1711 | return TRACE_TYPE_PARTIAL_LINE; | |
1712 | } | |
1713 | ||
413d37d1 MH |
1714 | #undef DEFINE_FIELD |
1715 | #define DEFINE_FIELD(type, item, name, is_signed) \ | |
1716 | do { \ | |
1717 | ret = trace_define_field(event_call, #type, name, \ | |
1718 | offsetof(typeof(field), item), \ | |
1719 | sizeof(field.item), is_signed, \ | |
1720 | FILTER_OTHER); \ | |
1721 | if (ret) \ | |
1722 | return ret; \ | |
1723 | } while (0) | |
1724 | ||
1725 | static int kprobe_event_define_fields(struct ftrace_event_call *event_call) | |
1726 | { | |
1727 | int ret, i; | |
93ccae7a | 1728 | struct kprobe_trace_entry_head field; |
413d37d1 MH |
1729 | struct trace_probe *tp = (struct trace_probe *)event_call->data; |
1730 | ||
a703d946 | 1731 | DEFINE_FIELD(unsigned long, ip, FIELD_STRING_IP, 0); |
eca0d916 | 1732 | /* Set argument names as fields */ |
93ccae7a | 1733 | for (i = 0; i < tp->nr_args; i++) { |
e09c8614 | 1734 | ret = trace_define_field(event_call, tp->args[i].type->fmttype, |
93ccae7a MH |
1735 | tp->args[i].name, |
1736 | sizeof(field) + tp->args[i].offset, | |
1737 | tp->args[i].type->size, | |
1738 | tp->args[i].type->is_signed, | |
1739 | FILTER_OTHER); | |
1740 | if (ret) | |
1741 | return ret; | |
1742 | } | |
413d37d1 MH |
1743 | return 0; |
1744 | } | |
1745 | ||
1746 | static int kretprobe_event_define_fields(struct ftrace_event_call *event_call) | |
1747 | { | |
1748 | int ret, i; | |
93ccae7a | 1749 | struct kretprobe_trace_entry_head field; |
413d37d1 MH |
1750 | struct trace_probe *tp = (struct trace_probe *)event_call->data; |
1751 | ||
a703d946 MH |
1752 | DEFINE_FIELD(unsigned long, func, FIELD_STRING_FUNC, 0); |
1753 | DEFINE_FIELD(unsigned long, ret_ip, FIELD_STRING_RETIP, 0); | |
eca0d916 | 1754 | /* Set argument names as fields */ |
93ccae7a | 1755 | for (i = 0; i < tp->nr_args; i++) { |
e09c8614 | 1756 | ret = trace_define_field(event_call, tp->args[i].type->fmttype, |
93ccae7a MH |
1757 | tp->args[i].name, |
1758 | sizeof(field) + tp->args[i].offset, | |
1759 | tp->args[i].type->size, | |
1760 | tp->args[i].type->is_signed, | |
1761 | FILTER_OTHER); | |
1762 | if (ret) | |
1763 | return ret; | |
1764 | } | |
413d37d1 MH |
1765 | return 0; |
1766 | } | |
1767 | ||
a342a028 LJ |
1768 | static int __set_print_fmt(struct trace_probe *tp, char *buf, int len) |
1769 | { | |
1770 | int i; | |
1771 | int pos = 0; | |
1772 | ||
1773 | const char *fmt, *arg; | |
1774 | ||
7143f168 | 1775 | if (!trace_probe_is_return(tp)) { |
a342a028 LJ |
1776 | fmt = "(%lx)"; |
1777 | arg = "REC->" FIELD_STRING_IP; | |
1778 | } else { | |
1779 | fmt = "(%lx <- %lx)"; | |
1780 | arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP; | |
1781 | } | |
1782 | ||
1783 | /* When len=0, we just calculate the needed length */ | |
1784 | #define LEN_OR_ZERO (len ? len - pos : 0) | |
1785 | ||
1786 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt); | |
1787 | ||
1788 | for (i = 0; i < tp->nr_args; i++) { | |
93ccae7a MH |
1789 | pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s", |
1790 | tp->args[i].name, tp->args[i].type->fmt); | |
a342a028 LJ |
1791 | } |
1792 | ||
1793 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg); | |
1794 | ||
1795 | for (i = 0; i < tp->nr_args; i++) { | |
e09c8614 MH |
1796 | if (strcmp(tp->args[i].type->name, "string") == 0) |
1797 | pos += snprintf(buf + pos, LEN_OR_ZERO, | |
1798 | ", __get_str(%s)", | |
1799 | tp->args[i].name); | |
1800 | else | |
1801 | pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s", | |
1802 | tp->args[i].name); | |
a342a028 LJ |
1803 | } |
1804 | ||
1805 | #undef LEN_OR_ZERO | |
1806 | ||
1807 | /* return the length of print_fmt */ | |
1808 | return pos; | |
1809 | } | |
1810 | ||
1811 | static int set_print_fmt(struct trace_probe *tp) | |
1812 | { | |
1813 | int len; | |
1814 | char *print_fmt; | |
1815 | ||
1816 | /* First: called with 0 length to calculate the needed length */ | |
1817 | len = __set_print_fmt(tp, NULL, 0); | |
1818 | print_fmt = kmalloc(len + 1, GFP_KERNEL); | |
1819 | if (!print_fmt) | |
1820 | return -ENOMEM; | |
1821 | ||
1822 | /* Second: actually write the @print_fmt */ | |
1823 | __set_print_fmt(tp, print_fmt, len + 1); | |
1824 | tp->call.print_fmt = print_fmt; | |
1825 | ||
1826 | return 0; | |
1827 | } | |
1828 | ||
07b139c8 | 1829 | #ifdef CONFIG_PERF_EVENTS |
e08d1c65 MH |
1830 | |
1831 | /* Kprobe profile handler */ | |
97d5a220 | 1832 | static __kprobes void kprobe_perf_func(struct kprobe *kp, |
e08d1c65 MH |
1833 | struct pt_regs *regs) |
1834 | { | |
1835 | struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); | |
1836 | struct ftrace_event_call *call = &tp->call; | |
93ccae7a | 1837 | struct kprobe_trace_entry_head *entry; |
1c024eca | 1838 | struct hlist_head *head; |
e09c8614 | 1839 | int size, __size, dsize; |
4ed7c92d | 1840 | int rctx; |
e08d1c65 | 1841 | |
e09c8614 MH |
1842 | dsize = __get_data_size(tp, regs); |
1843 | __size = sizeof(*entry) + tp->size + dsize; | |
74ebb63e MH |
1844 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
1845 | size -= sizeof(u32); | |
97d5a220 | 1846 | if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, |
a1a138d0 | 1847 | "profile buffer not large enough")) |
1e12a4a7 | 1848 | return; |
ce71b9df | 1849 | |
ff5f149b | 1850 | entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx); |
430ad5a6 | 1851 | if (!entry) |
1e12a4a7 | 1852 | return; |
a1a138d0 | 1853 | |
a1a138d0 | 1854 | entry->ip = (unsigned long)kp->addr; |
e09c8614 MH |
1855 | memset(&entry[1], 0, dsize); |
1856 | store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); | |
444a2a3b | 1857 | |
3771f077 | 1858 | head = this_cpu_ptr(call->perf_events); |
1c024eca | 1859 | perf_trace_buf_submit(entry, size, rctx, entry->ip, 1, regs, head); |
e08d1c65 MH |
1860 | } |
1861 | ||
1862 | /* Kretprobe profile handler */ | |
97d5a220 | 1863 | static __kprobes void kretprobe_perf_func(struct kretprobe_instance *ri, |
e08d1c65 MH |
1864 | struct pt_regs *regs) |
1865 | { | |
1866 | struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); | |
1867 | struct ftrace_event_call *call = &tp->call; | |
93ccae7a | 1868 | struct kretprobe_trace_entry_head *entry; |
1c024eca | 1869 | struct hlist_head *head; |
e09c8614 | 1870 | int size, __size, dsize; |
4ed7c92d | 1871 | int rctx; |
e08d1c65 | 1872 | |
e09c8614 MH |
1873 | dsize = __get_data_size(tp, regs); |
1874 | __size = sizeof(*entry) + tp->size + dsize; | |
74ebb63e MH |
1875 | size = ALIGN(__size + sizeof(u32), sizeof(u64)); |
1876 | size -= sizeof(u32); | |
97d5a220 | 1877 | if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, |
a1a138d0 | 1878 | "profile buffer not large enough")) |
1e12a4a7 | 1879 | return; |
444a2a3b | 1880 | |
ff5f149b | 1881 | entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx); |
430ad5a6 | 1882 | if (!entry) |
1e12a4a7 | 1883 | return; |
e08d1c65 | 1884 | |
a1a138d0 MH |
1885 | entry->func = (unsigned long)tp->rp.kp.addr; |
1886 | entry->ret_ip = (unsigned long)ri->ret_addr; | |
e09c8614 | 1887 | store_trace_args(sizeof(*entry), tp, regs, (u8 *)&entry[1], dsize); |
444a2a3b | 1888 | |
3771f077 | 1889 | head = this_cpu_ptr(call->perf_events); |
1c024eca | 1890 | perf_trace_buf_submit(entry, size, rctx, entry->ret_ip, 1, regs, head); |
e08d1c65 | 1891 | } |
07b139c8 | 1892 | #endif /* CONFIG_PERF_EVENTS */ |
50d78056 | 1893 | |
2239291a | 1894 | static __kprobes |
ceec0b6f JO |
1895 | int kprobe_register(struct ftrace_event_call *event, |
1896 | enum trace_reg type, void *data) | |
2239291a | 1897 | { |
1538f888 MH |
1898 | struct trace_probe *tp = (struct trace_probe *)event->data; |
1899 | ||
2239291a SR |
1900 | switch (type) { |
1901 | case TRACE_REG_REGISTER: | |
1538f888 | 1902 | return enable_trace_probe(tp, TP_FLAG_TRACE); |
2239291a | 1903 | case TRACE_REG_UNREGISTER: |
1538f888 | 1904 | disable_trace_probe(tp, TP_FLAG_TRACE); |
2239291a SR |
1905 | return 0; |
1906 | ||
1907 | #ifdef CONFIG_PERF_EVENTS | |
1908 | case TRACE_REG_PERF_REGISTER: | |
1538f888 | 1909 | return enable_trace_probe(tp, TP_FLAG_PROFILE); |
2239291a | 1910 | case TRACE_REG_PERF_UNREGISTER: |
1538f888 | 1911 | disable_trace_probe(tp, TP_FLAG_PROFILE); |
2239291a | 1912 | return 0; |
ceec0b6f JO |
1913 | case TRACE_REG_PERF_OPEN: |
1914 | case TRACE_REG_PERF_CLOSE: | |
489c75c3 JO |
1915 | case TRACE_REG_PERF_ADD: |
1916 | case TRACE_REG_PERF_DEL: | |
ceec0b6f | 1917 | return 0; |
2239291a SR |
1918 | #endif |
1919 | } | |
1920 | return 0; | |
1921 | } | |
50d78056 MH |
1922 | |
1923 | static __kprobes | |
1924 | int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) | |
1925 | { | |
1926 | struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); | |
e08d1c65 | 1927 | |
50d78056 MH |
1928 | if (tp->flags & TP_FLAG_TRACE) |
1929 | kprobe_trace_func(kp, regs); | |
07b139c8 | 1930 | #ifdef CONFIG_PERF_EVENTS |
50d78056 | 1931 | if (tp->flags & TP_FLAG_PROFILE) |
97d5a220 | 1932 | kprobe_perf_func(kp, regs); |
07b139c8 | 1933 | #endif |
50d78056 MH |
1934 | return 0; /* We don't tweek kernel, so just return 0 */ |
1935 | } | |
1936 | ||
1937 | static __kprobes | |
1938 | int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) | |
1939 | { | |
1940 | struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); | |
1941 | ||
1942 | if (tp->flags & TP_FLAG_TRACE) | |
1943 | kretprobe_trace_func(ri, regs); | |
07b139c8 | 1944 | #ifdef CONFIG_PERF_EVENTS |
50d78056 | 1945 | if (tp->flags & TP_FLAG_PROFILE) |
97d5a220 | 1946 | kretprobe_perf_func(ri, regs); |
07b139c8 | 1947 | #endif |
50d78056 MH |
1948 | return 0; /* We don't tweek kernel, so just return 0 */ |
1949 | } | |
e08d1c65 | 1950 | |
a9a57763 SR |
1951 | static struct trace_event_functions kretprobe_funcs = { |
1952 | .trace = print_kretprobe_event | |
1953 | }; | |
1954 | ||
1955 | static struct trace_event_functions kprobe_funcs = { | |
1956 | .trace = print_kprobe_event | |
1957 | }; | |
1958 | ||
413d37d1 MH |
1959 | static int register_probe_event(struct trace_probe *tp) |
1960 | { | |
1961 | struct ftrace_event_call *call = &tp->call; | |
1962 | int ret; | |
1963 | ||
1964 | /* Initialize ftrace_event_call */ | |
ffb9f995 | 1965 | INIT_LIST_HEAD(&call->class->fields); |
7143f168 | 1966 | if (trace_probe_is_return(tp)) { |
80decc70 | 1967 | call->event.funcs = &kretprobe_funcs; |
2e33af02 | 1968 | call->class->define_fields = kretprobe_event_define_fields; |
413d37d1 | 1969 | } else { |
80decc70 | 1970 | call->event.funcs = &kprobe_funcs; |
2e33af02 | 1971 | call->class->define_fields = kprobe_event_define_fields; |
413d37d1 | 1972 | } |
a342a028 LJ |
1973 | if (set_print_fmt(tp) < 0) |
1974 | return -ENOMEM; | |
32c0edae SR |
1975 | ret = register_ftrace_event(&call->event); |
1976 | if (!ret) { | |
a342a028 | 1977 | kfree(call->print_fmt); |
ff50d991 | 1978 | return -ENODEV; |
a342a028 | 1979 | } |
553552ce | 1980 | call->flags = 0; |
2239291a | 1981 | call->class->reg = kprobe_register; |
413d37d1 MH |
1982 | call->data = tp; |
1983 | ret = trace_add_event_call(call); | |
ff50d991 | 1984 | if (ret) { |
413d37d1 | 1985 | pr_info("Failed to register kprobe event: %s\n", call->name); |
a342a028 | 1986 | kfree(call->print_fmt); |
80decc70 | 1987 | unregister_ftrace_event(&call->event); |
ff50d991 | 1988 | } |
413d37d1 MH |
1989 | return ret; |
1990 | } | |
1991 | ||
1992 | static void unregister_probe_event(struct trace_probe *tp) | |
1993 | { | |
ff50d991 | 1994 | /* tp->event is unregistered in trace_remove_event_call() */ |
413d37d1 | 1995 | trace_remove_event_call(&tp->call); |
a342a028 | 1996 | kfree(tp->call.print_fmt); |
413d37d1 MH |
1997 | } |
1998 | ||
25985edc | 1999 | /* Make a debugfs interface for controlling probe points */ |
413d37d1 MH |
2000 | static __init int init_kprobe_trace(void) |
2001 | { | |
2002 | struct dentry *d_tracer; | |
2003 | struct dentry *entry; | |
413d37d1 | 2004 | |
61424318 MH |
2005 | if (register_module_notifier(&trace_probe_module_nb)) |
2006 | return -EINVAL; | |
2007 | ||
413d37d1 MH |
2008 | d_tracer = tracing_init_dentry(); |
2009 | if (!d_tracer) | |
2010 | return 0; | |
2011 | ||
2012 | entry = debugfs_create_file("kprobe_events", 0644, d_tracer, | |
2013 | NULL, &kprobe_events_ops); | |
2014 | ||
cd7e7bd5 | 2015 | /* Event list interface */ |
413d37d1 MH |
2016 | if (!entry) |
2017 | pr_warning("Could not create debugfs " | |
2018 | "'kprobe_events' entry\n"); | |
cd7e7bd5 MH |
2019 | |
2020 | /* Profile interface */ | |
2021 | entry = debugfs_create_file("kprobe_profile", 0444, d_tracer, | |
2022 | NULL, &kprobe_profile_ops); | |
2023 | ||
2024 | if (!entry) | |
2025 | pr_warning("Could not create debugfs " | |
2026 | "'kprobe_profile' entry\n"); | |
413d37d1 MH |
2027 | return 0; |
2028 | } | |
2029 | fs_initcall(init_kprobe_trace); | |
2030 | ||
2031 | ||
2032 | #ifdef CONFIG_FTRACE_STARTUP_TEST | |
2033 | ||
265a5b7e SR |
2034 | /* |
2035 | * The "__used" keeps gcc from removing the function symbol | |
2036 | * from the kallsyms table. | |
2037 | */ | |
2038 | static __used int kprobe_trace_selftest_target(int a1, int a2, int a3, | |
2039 | int a4, int a5, int a6) | |
413d37d1 MH |
2040 | { |
2041 | return a1 + a2 + a3 + a4 + a5 + a6; | |
2042 | } | |
2043 | ||
2044 | static __init int kprobe_trace_self_tests_init(void) | |
2045 | { | |
231e36f4 | 2046 | int ret, warn = 0; |
413d37d1 | 2047 | int (*target)(int, int, int, int, int, int); |
231e36f4 | 2048 | struct trace_probe *tp; |
413d37d1 MH |
2049 | |
2050 | target = kprobe_trace_selftest_target; | |
2051 | ||
2052 | pr_info("Testing kprobe tracing: "); | |
2053 | ||
2054 | ret = command_trace_probe("p:testprobe kprobe_trace_selftest_target " | |
231e36f4 MH |
2055 | "$stack $stack0 +0($stack)"); |
2056 | if (WARN_ON_ONCE(ret)) { | |
2057 | pr_warning("error on probing function entry.\n"); | |
2058 | warn++; | |
2059 | } else { | |
2060 | /* Enable trace point */ | |
7143f168 | 2061 | tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM); |
231e36f4 MH |
2062 | if (WARN_ON_ONCE(tp == NULL)) { |
2063 | pr_warning("error on getting new probe.\n"); | |
2064 | warn++; | |
2065 | } else | |
1538f888 | 2066 | enable_trace_probe(tp, TP_FLAG_TRACE); |
231e36f4 | 2067 | } |
413d37d1 MH |
2068 | |
2069 | ret = command_trace_probe("r:testprobe2 kprobe_trace_selftest_target " | |
f397af06 | 2070 | "$retval"); |
231e36f4 MH |
2071 | if (WARN_ON_ONCE(ret)) { |
2072 | pr_warning("error on probing function return.\n"); | |
2073 | warn++; | |
2074 | } else { | |
2075 | /* Enable trace point */ | |
7143f168 | 2076 | tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM); |
231e36f4 MH |
2077 | if (WARN_ON_ONCE(tp == NULL)) { |
2078 | pr_warning("error on getting new probe.\n"); | |
2079 | warn++; | |
2080 | } else | |
1538f888 | 2081 | enable_trace_probe(tp, TP_FLAG_TRACE); |
231e36f4 MH |
2082 | } |
2083 | ||
2084 | if (warn) | |
2085 | goto end; | |
413d37d1 MH |
2086 | |
2087 | ret = target(1, 2, 3, 4, 5, 6); | |
2088 | ||
02ca1521 MH |
2089 | /* Disable trace points before removing it */ |
2090 | tp = find_trace_probe("testprobe", KPROBE_EVENT_SYSTEM); | |
2091 | if (WARN_ON_ONCE(tp == NULL)) { | |
2092 | pr_warning("error on getting test probe.\n"); | |
2093 | warn++; | |
2094 | } else | |
2095 | disable_trace_probe(tp, TP_FLAG_TRACE); | |
2096 | ||
2097 | tp = find_trace_probe("testprobe2", KPROBE_EVENT_SYSTEM); | |
2098 | if (WARN_ON_ONCE(tp == NULL)) { | |
2099 | pr_warning("error on getting 2nd test probe.\n"); | |
2100 | warn++; | |
2101 | } else | |
2102 | disable_trace_probe(tp, TP_FLAG_TRACE); | |
2103 | ||
231e36f4 MH |
2104 | ret = command_trace_probe("-:testprobe"); |
2105 | if (WARN_ON_ONCE(ret)) { | |
2106 | pr_warning("error on deleting a probe.\n"); | |
2107 | warn++; | |
2108 | } | |
2109 | ||
2110 | ret = command_trace_probe("-:testprobe2"); | |
2111 | if (WARN_ON_ONCE(ret)) { | |
2112 | pr_warning("error on deleting a probe.\n"); | |
2113 | warn++; | |
2114 | } | |
413d37d1 | 2115 | |
231e36f4 | 2116 | end: |
7143f168 | 2117 | release_all_trace_probes(); |
231e36f4 MH |
2118 | if (warn) |
2119 | pr_cont("NG: Some tests are failed. Please check them.\n"); | |
2120 | else | |
2121 | pr_cont("OK\n"); | |
413d37d1 MH |
2122 | return 0; |
2123 | } | |
2124 | ||
2125 | late_initcall(kprobe_trace_self_tests_init); | |
2126 | ||
2127 | #endif |