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Commit | Line | Data |
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8ab83f56 SD |
1 | /* |
2 | * Common code for probe-based Dynamic events. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License version 2 as | |
6 | * published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
11 | * GNU General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public License | |
14 | * along with this program; if not, write to the Free Software | |
15 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
16 | * | |
17 | * This code was copied from kernel/trace/trace_kprobe.c written by | |
18 | * Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> | |
19 | * | |
20 | * Updates to make this generic: | |
21 | * Copyright (C) IBM Corporation, 2010-2011 | |
22 | * Author: Srikar Dronamraju | |
23 | */ | |
24 | ||
25 | #include "trace_probe.h" | |
26 | ||
27 | const char *reserved_field_names[] = { | |
28 | "common_type", | |
29 | "common_flags", | |
30 | "common_preempt_count", | |
31 | "common_pid", | |
32 | "common_tgid", | |
33 | FIELD_STRING_IP, | |
34 | FIELD_STRING_RETIP, | |
35 | FIELD_STRING_FUNC, | |
36 | }; | |
37 | ||
8ab83f56 | 38 | /* Printing in basic type function template */ |
17ce3dc7 MH |
39 | #define DEFINE_BASIC_PRINT_TYPE_FUNC(tname, type, fmt) \ |
40 | int PRINT_TYPE_FUNC_NAME(tname)(struct trace_seq *s, const char *name, \ | |
3da0f180 | 41 | void *data, void *ent) \ |
8ab83f56 | 42 | { \ |
d2b0191a SRRH |
43 | trace_seq_printf(s, " %s=" fmt, name, *(type *)data); \ |
44 | return !trace_seq_has_overflowed(s); \ | |
8ab83f56 | 45 | } \ |
17ce3dc7 MH |
46 | const char PRINT_TYPE_FMT_NAME(tname)[] = fmt; \ |
47 | NOKPROBE_SYMBOL(PRINT_TYPE_FUNC_NAME(tname)); | |
8ab83f56 | 48 | |
17ce3dc7 MH |
49 | DEFINE_BASIC_PRINT_TYPE_FUNC(u8, u8, "0x%x") |
50 | DEFINE_BASIC_PRINT_TYPE_FUNC(u16, u16, "0x%x") | |
51 | DEFINE_BASIC_PRINT_TYPE_FUNC(u32, u32, "0x%x") | |
52 | DEFINE_BASIC_PRINT_TYPE_FUNC(u64, u64, "0x%Lx") | |
53 | DEFINE_BASIC_PRINT_TYPE_FUNC(s8, s8, "%d") | |
54 | DEFINE_BASIC_PRINT_TYPE_FUNC(s16, s16, "%d") | |
55 | DEFINE_BASIC_PRINT_TYPE_FUNC(s32, s32, "%d") | |
56 | DEFINE_BASIC_PRINT_TYPE_FUNC(s64, s64, "%Ld") | |
57 | DEFINE_BASIC_PRINT_TYPE_FUNC(x8, u8, "0x%x") | |
58 | DEFINE_BASIC_PRINT_TYPE_FUNC(x16, u16, "0x%x") | |
59 | DEFINE_BASIC_PRINT_TYPE_FUNC(x32, u32, "0x%x") | |
60 | DEFINE_BASIC_PRINT_TYPE_FUNC(x64, u64, "0x%Lx") | |
8ab83f56 | 61 | |
8ab83f56 | 62 | /* Print type function for string type */ |
3da0f180 MH |
63 | int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, const char *name, |
64 | void *data, void *ent) | |
8ab83f56 SD |
65 | { |
66 | int len = *(u32 *)data >> 16; | |
67 | ||
68 | if (!len) | |
d2b0191a | 69 | trace_seq_printf(s, " %s=(fault)", name); |
8ab83f56 | 70 | else |
d2b0191a SRRH |
71 | trace_seq_printf(s, " %s=\"%s\"", name, |
72 | (const char *)get_loc_data(data, ent)); | |
73 | return !trace_seq_has_overflowed(s); | |
8ab83f56 | 74 | } |
3da0f180 | 75 | NOKPROBE_SYMBOL(PRINT_TYPE_FUNC_NAME(string)); |
8ab83f56 | 76 | |
b26c74e1 | 77 | const char PRINT_TYPE_FMT_NAME(string)[] = "\\\"%s\\\""; |
8ab83f56 | 78 | |
8ab83f56 SD |
79 | #define CHECK_FETCH_FUNCS(method, fn) \ |
80 | (((FETCH_FUNC_NAME(method, u8) == fn) || \ | |
81 | (FETCH_FUNC_NAME(method, u16) == fn) || \ | |
82 | (FETCH_FUNC_NAME(method, u32) == fn) || \ | |
83 | (FETCH_FUNC_NAME(method, u64) == fn) || \ | |
84 | (FETCH_FUNC_NAME(method, string) == fn) || \ | |
85 | (FETCH_FUNC_NAME(method, string_size) == fn)) \ | |
86 | && (fn != NULL)) | |
87 | ||
88 | /* Data fetch function templates */ | |
89 | #define DEFINE_FETCH_reg(type) \ | |
3da0f180 | 90 | void FETCH_FUNC_NAME(reg, type)(struct pt_regs *regs, void *offset, void *dest) \ |
8ab83f56 SD |
91 | { \ |
92 | *(type *)dest = (type)regs_get_register(regs, \ | |
93 | (unsigned int)((unsigned long)offset)); \ | |
3da0f180 MH |
94 | } \ |
95 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(reg, type)); | |
8ab83f56 SD |
96 | DEFINE_BASIC_FETCH_FUNCS(reg) |
97 | /* No string on the register */ | |
98 | #define fetch_reg_string NULL | |
99 | #define fetch_reg_string_size NULL | |
100 | ||
8ab83f56 | 101 | #define DEFINE_FETCH_retval(type) \ |
3da0f180 MH |
102 | void FETCH_FUNC_NAME(retval, type)(struct pt_regs *regs, \ |
103 | void *dummy, void *dest) \ | |
8ab83f56 SD |
104 | { \ |
105 | *(type *)dest = (type)regs_return_value(regs); \ | |
3da0f180 MH |
106 | } \ |
107 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(retval, type)); | |
8ab83f56 SD |
108 | DEFINE_BASIC_FETCH_FUNCS(retval) |
109 | /* No string on the retval */ | |
110 | #define fetch_retval_string NULL | |
111 | #define fetch_retval_string_size NULL | |
112 | ||
8ab83f56 SD |
113 | /* Dereference memory access function */ |
114 | struct deref_fetch_param { | |
115 | struct fetch_param orig; | |
116 | long offset; | |
3925f4a5 HL |
117 | fetch_func_t fetch; |
118 | fetch_func_t fetch_size; | |
8ab83f56 SD |
119 | }; |
120 | ||
121 | #define DEFINE_FETCH_deref(type) \ | |
3da0f180 MH |
122 | void FETCH_FUNC_NAME(deref, type)(struct pt_regs *regs, \ |
123 | void *data, void *dest) \ | |
8ab83f56 SD |
124 | { \ |
125 | struct deref_fetch_param *dprm = data; \ | |
126 | unsigned long addr; \ | |
127 | call_fetch(&dprm->orig, regs, &addr); \ | |
128 | if (addr) { \ | |
129 | addr += dprm->offset; \ | |
3925f4a5 | 130 | dprm->fetch(regs, (void *)addr, dest); \ |
8ab83f56 SD |
131 | } else \ |
132 | *(type *)dest = 0; \ | |
3da0f180 MH |
133 | } \ |
134 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(deref, type)); | |
8ab83f56 SD |
135 | DEFINE_BASIC_FETCH_FUNCS(deref) |
136 | DEFINE_FETCH_deref(string) | |
3925f4a5 | 137 | |
3da0f180 MH |
138 | void FETCH_FUNC_NAME(deref, string_size)(struct pt_regs *regs, |
139 | void *data, void *dest) | |
3925f4a5 HL |
140 | { |
141 | struct deref_fetch_param *dprm = data; | |
142 | unsigned long addr; | |
143 | ||
144 | call_fetch(&dprm->orig, regs, &addr); | |
145 | if (addr && dprm->fetch_size) { | |
146 | addr += dprm->offset; | |
147 | dprm->fetch_size(regs, (void *)addr, dest); | |
148 | } else | |
149 | *(string_size *)dest = 0; | |
150 | } | |
3da0f180 | 151 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(deref, string_size)); |
8ab83f56 | 152 | |
3da0f180 | 153 | static void update_deref_fetch_param(struct deref_fetch_param *data) |
8ab83f56 SD |
154 | { |
155 | if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) | |
156 | update_deref_fetch_param(data->orig.data); | |
157 | else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) | |
158 | update_symbol_cache(data->orig.data); | |
159 | } | |
3da0f180 | 160 | NOKPROBE_SYMBOL(update_deref_fetch_param); |
8ab83f56 | 161 | |
3da0f180 | 162 | static void free_deref_fetch_param(struct deref_fetch_param *data) |
8ab83f56 SD |
163 | { |
164 | if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) | |
165 | free_deref_fetch_param(data->orig.data); | |
166 | else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) | |
167 | free_symbol_cache(data->orig.data); | |
168 | kfree(data); | |
169 | } | |
3da0f180 | 170 | NOKPROBE_SYMBOL(free_deref_fetch_param); |
8ab83f56 SD |
171 | |
172 | /* Bitfield fetch function */ | |
173 | struct bitfield_fetch_param { | |
174 | struct fetch_param orig; | |
175 | unsigned char hi_shift; | |
176 | unsigned char low_shift; | |
177 | }; | |
178 | ||
179 | #define DEFINE_FETCH_bitfield(type) \ | |
3da0f180 MH |
180 | void FETCH_FUNC_NAME(bitfield, type)(struct pt_regs *regs, \ |
181 | void *data, void *dest) \ | |
8ab83f56 SD |
182 | { \ |
183 | struct bitfield_fetch_param *bprm = data; \ | |
184 | type buf = 0; \ | |
185 | call_fetch(&bprm->orig, regs, &buf); \ | |
186 | if (buf) { \ | |
187 | buf <<= bprm->hi_shift; \ | |
188 | buf >>= bprm->low_shift; \ | |
189 | } \ | |
190 | *(type *)dest = buf; \ | |
3da0f180 MH |
191 | } \ |
192 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(bitfield, type)); | |
8ab83f56 SD |
193 | DEFINE_BASIC_FETCH_FUNCS(bitfield) |
194 | #define fetch_bitfield_string NULL | |
195 | #define fetch_bitfield_string_size NULL | |
196 | ||
fbc1963d | 197 | static void |
8ab83f56 SD |
198 | update_bitfield_fetch_param(struct bitfield_fetch_param *data) |
199 | { | |
200 | /* | |
201 | * Don't check the bitfield itself, because this must be the | |
202 | * last fetch function. | |
203 | */ | |
204 | if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) | |
205 | update_deref_fetch_param(data->orig.data); | |
206 | else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) | |
207 | update_symbol_cache(data->orig.data); | |
208 | } | |
209 | ||
fbc1963d | 210 | static void |
8ab83f56 SD |
211 | free_bitfield_fetch_param(struct bitfield_fetch_param *data) |
212 | { | |
213 | /* | |
214 | * Don't check the bitfield itself, because this must be the | |
215 | * last fetch function. | |
216 | */ | |
217 | if (CHECK_FETCH_FUNCS(deref, data->orig.fn)) | |
218 | free_deref_fetch_param(data->orig.data); | |
219 | else if (CHECK_FETCH_FUNCS(symbol, data->orig.fn)) | |
220 | free_symbol_cache(data->orig.data); | |
221 | ||
222 | kfree(data); | |
223 | } | |
224 | ||
35abb67d OS |
225 | void FETCH_FUNC_NAME(comm, string)(struct pt_regs *regs, |
226 | void *data, void *dest) | |
227 | { | |
228 | int maxlen = get_rloc_len(*(u32 *)dest); | |
229 | u8 *dst = get_rloc_data(dest); | |
230 | long ret; | |
231 | ||
232 | if (!maxlen) | |
233 | return; | |
234 | ||
235 | ret = strlcpy(dst, current->comm, maxlen); | |
236 | *(u32 *)dest = make_data_rloc(ret, get_rloc_offs(*(u32 *)dest)); | |
237 | } | |
238 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(comm, string)); | |
239 | ||
240 | void FETCH_FUNC_NAME(comm, string_size)(struct pt_regs *regs, | |
241 | void *data, void *dest) | |
242 | { | |
243 | *(u32 *)dest = strlen(current->comm) + 1; | |
244 | } | |
245 | NOKPROBE_SYMBOL(FETCH_FUNC_NAME(comm, string_size)); | |
246 | ||
34fee3a1 NK |
247 | static const struct fetch_type *find_fetch_type(const char *type, |
248 | const struct fetch_type *ftbl) | |
8ab83f56 SD |
249 | { |
250 | int i; | |
251 | ||
252 | if (!type) | |
253 | type = DEFAULT_FETCH_TYPE_STR; | |
254 | ||
255 | /* Special case: bitfield */ | |
256 | if (*type == 'b') { | |
257 | unsigned long bs; | |
258 | ||
259 | type = strchr(type, '/'); | |
260 | if (!type) | |
261 | goto fail; | |
262 | ||
263 | type++; | |
bcd83ea6 | 264 | if (kstrtoul(type, 0, &bs)) |
8ab83f56 SD |
265 | goto fail; |
266 | ||
267 | switch (bs) { | |
268 | case 8: | |
34fee3a1 | 269 | return find_fetch_type("u8", ftbl); |
8ab83f56 | 270 | case 16: |
34fee3a1 | 271 | return find_fetch_type("u16", ftbl); |
8ab83f56 | 272 | case 32: |
34fee3a1 | 273 | return find_fetch_type("u32", ftbl); |
8ab83f56 | 274 | case 64: |
34fee3a1 | 275 | return find_fetch_type("u64", ftbl); |
8ab83f56 SD |
276 | default: |
277 | goto fail; | |
278 | } | |
279 | } | |
280 | ||
34fee3a1 NK |
281 | for (i = 0; ftbl[i].name; i++) { |
282 | if (strcmp(type, ftbl[i].name) == 0) | |
283 | return &ftbl[i]; | |
284 | } | |
8ab83f56 SD |
285 | |
286 | fail: | |
287 | return NULL; | |
288 | } | |
289 | ||
290 | /* Special function : only accept unsigned long */ | |
3da0f180 | 291 | static void fetch_kernel_stack_address(struct pt_regs *regs, void *dummy, void *dest) |
8ab83f56 SD |
292 | { |
293 | *(unsigned long *)dest = kernel_stack_pointer(regs); | |
294 | } | |
3da0f180 | 295 | NOKPROBE_SYMBOL(fetch_kernel_stack_address); |
8ab83f56 | 296 | |
3da0f180 | 297 | static void fetch_user_stack_address(struct pt_regs *regs, void *dummy, void *dest) |
b079d374 NK |
298 | { |
299 | *(unsigned long *)dest = user_stack_pointer(regs); | |
300 | } | |
3da0f180 | 301 | NOKPROBE_SYMBOL(fetch_user_stack_address); |
b079d374 | 302 | |
8ab83f56 | 303 | static fetch_func_t get_fetch_size_function(const struct fetch_type *type, |
34fee3a1 NK |
304 | fetch_func_t orig_fn, |
305 | const struct fetch_type *ftbl) | |
8ab83f56 SD |
306 | { |
307 | int i; | |
308 | ||
34fee3a1 | 309 | if (type != &ftbl[FETCH_TYPE_STRING]) |
8ab83f56 SD |
310 | return NULL; /* Only string type needs size function */ |
311 | ||
312 | for (i = 0; i < FETCH_MTD_END; i++) | |
313 | if (type->fetch[i] == orig_fn) | |
34fee3a1 | 314 | return ftbl[FETCH_TYPE_STRSIZE].fetch[i]; |
8ab83f56 SD |
315 | |
316 | WARN_ON(1); /* This should not happen */ | |
317 | ||
318 | return NULL; | |
319 | } | |
320 | ||
321 | /* Split symbol and offset. */ | |
322 | int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset) | |
323 | { | |
324 | char *tmp; | |
325 | int ret; | |
326 | ||
327 | if (!offset) | |
328 | return -EINVAL; | |
329 | ||
330 | tmp = strchr(symbol, '+'); | |
331 | if (tmp) { | |
bcd83ea6 DW |
332 | /* skip sign because kstrtoul doesn't accept '+' */ |
333 | ret = kstrtoul(tmp + 1, 0, offset); | |
8ab83f56 SD |
334 | if (ret) |
335 | return ret; | |
336 | ||
337 | *tmp = '\0'; | |
338 | } else | |
339 | *offset = 0; | |
340 | ||
341 | return 0; | |
342 | } | |
343 | ||
344 | #define PARAM_MAX_STACK (THREAD_SIZE / sizeof(unsigned long)) | |
345 | ||
346 | static int parse_probe_vars(char *arg, const struct fetch_type *t, | |
b079d374 NK |
347 | struct fetch_param *f, bool is_return, |
348 | bool is_kprobe) | |
8ab83f56 SD |
349 | { |
350 | int ret = 0; | |
351 | unsigned long param; | |
352 | ||
353 | if (strcmp(arg, "retval") == 0) { | |
354 | if (is_return) | |
355 | f->fn = t->fetch[FETCH_MTD_retval]; | |
356 | else | |
357 | ret = -EINVAL; | |
358 | } else if (strncmp(arg, "stack", 5) == 0) { | |
359 | if (arg[5] == '\0') { | |
b079d374 NK |
360 | if (strcmp(t->name, DEFAULT_FETCH_TYPE_STR)) |
361 | return -EINVAL; | |
362 | ||
363 | if (is_kprobe) | |
364 | f->fn = fetch_kernel_stack_address; | |
8ab83f56 | 365 | else |
b079d374 | 366 | f->fn = fetch_user_stack_address; |
8ab83f56 | 367 | } else if (isdigit(arg[5])) { |
bcd83ea6 | 368 | ret = kstrtoul(arg + 5, 10, ¶m); |
b079d374 | 369 | if (ret || (is_kprobe && param > PARAM_MAX_STACK)) |
8ab83f56 SD |
370 | ret = -EINVAL; |
371 | else { | |
372 | f->fn = t->fetch[FETCH_MTD_stack]; | |
373 | f->data = (void *)param; | |
374 | } | |
375 | } else | |
376 | ret = -EINVAL; | |
35abb67d OS |
377 | } else if (strcmp(arg, "comm") == 0) { |
378 | if (strcmp(t->name, "string") != 0 && | |
379 | strcmp(t->name, "string_size") != 0) | |
380 | return -EINVAL; | |
381 | f->fn = t->fetch[FETCH_MTD_comm]; | |
8ab83f56 SD |
382 | } else |
383 | ret = -EINVAL; | |
384 | ||
385 | return ret; | |
386 | } | |
387 | ||
388 | /* Recursive argument parser */ | |
389 | static int parse_probe_arg(char *arg, const struct fetch_type *t, | |
d9a16d3a SR |
390 | struct fetch_param *f, bool is_return, bool is_kprobe, |
391 | const struct fetch_type *ftbl) | |
8ab83f56 SD |
392 | { |
393 | unsigned long param; | |
394 | long offset; | |
395 | char *tmp; | |
34fee3a1 | 396 | int ret = 0; |
8ab83f56 | 397 | |
8ab83f56 SD |
398 | switch (arg[0]) { |
399 | case '$': | |
b079d374 | 400 | ret = parse_probe_vars(arg + 1, t, f, is_return, is_kprobe); |
8ab83f56 SD |
401 | break; |
402 | ||
403 | case '%': /* named register */ | |
404 | ret = regs_query_register_offset(arg + 1); | |
405 | if (ret >= 0) { | |
406 | f->fn = t->fetch[FETCH_MTD_reg]; | |
407 | f->data = (void *)(unsigned long)ret; | |
408 | ret = 0; | |
409 | } | |
410 | break; | |
411 | ||
b7e0bf34 | 412 | case '@': /* memory, file-offset or symbol */ |
8ab83f56 | 413 | if (isdigit(arg[1])) { |
bcd83ea6 | 414 | ret = kstrtoul(arg + 1, 0, ¶m); |
8ab83f56 SD |
415 | if (ret) |
416 | break; | |
417 | ||
418 | f->fn = t->fetch[FETCH_MTD_memory]; | |
419 | f->data = (void *)param; | |
b7e0bf34 NK |
420 | } else if (arg[1] == '+') { |
421 | /* kprobes don't support file offsets */ | |
422 | if (is_kprobe) | |
423 | return -EINVAL; | |
424 | ||
425 | ret = kstrtol(arg + 2, 0, &offset); | |
426 | if (ret) | |
427 | break; | |
428 | ||
429 | f->fn = t->fetch[FETCH_MTD_file_offset]; | |
430 | f->data = (void *)offset; | |
8ab83f56 | 431 | } else { |
b079d374 NK |
432 | /* uprobes don't support symbols */ |
433 | if (!is_kprobe) | |
434 | return -EINVAL; | |
435 | ||
8ab83f56 SD |
436 | ret = traceprobe_split_symbol_offset(arg + 1, &offset); |
437 | if (ret) | |
438 | break; | |
439 | ||
440 | f->data = alloc_symbol_cache(arg + 1, offset); | |
441 | if (f->data) | |
442 | f->fn = t->fetch[FETCH_MTD_symbol]; | |
443 | } | |
444 | break; | |
445 | ||
446 | case '+': /* deref memory */ | |
bcd83ea6 | 447 | arg++; /* Skip '+', because kstrtol() rejects it. */ |
8ab83f56 SD |
448 | case '-': |
449 | tmp = strchr(arg, '('); | |
450 | if (!tmp) | |
451 | break; | |
452 | ||
453 | *tmp = '\0'; | |
bcd83ea6 | 454 | ret = kstrtol(arg, 0, &offset); |
8ab83f56 SD |
455 | |
456 | if (ret) | |
457 | break; | |
458 | ||
459 | arg = tmp + 1; | |
460 | tmp = strrchr(arg, ')'); | |
461 | ||
462 | if (tmp) { | |
463 | struct deref_fetch_param *dprm; | |
464 | const struct fetch_type *t2; | |
465 | ||
34fee3a1 | 466 | t2 = find_fetch_type(NULL, ftbl); |
8ab83f56 SD |
467 | *tmp = '\0'; |
468 | dprm = kzalloc(sizeof(struct deref_fetch_param), GFP_KERNEL); | |
469 | ||
470 | if (!dprm) | |
471 | return -ENOMEM; | |
472 | ||
473 | dprm->offset = offset; | |
3925f4a5 HL |
474 | dprm->fetch = t->fetch[FETCH_MTD_memory]; |
475 | dprm->fetch_size = get_fetch_size_function(t, | |
476 | dprm->fetch, ftbl); | |
f3f096cf | 477 | ret = parse_probe_arg(arg, t2, &dprm->orig, is_return, |
d9a16d3a | 478 | is_kprobe, ftbl); |
8ab83f56 SD |
479 | if (ret) |
480 | kfree(dprm); | |
481 | else { | |
482 | f->fn = t->fetch[FETCH_MTD_deref]; | |
483 | f->data = (void *)dprm; | |
484 | } | |
485 | } | |
486 | break; | |
487 | } | |
488 | if (!ret && !f->fn) { /* Parsed, but do not find fetch method */ | |
489 | pr_info("%s type has no corresponding fetch method.\n", t->name); | |
490 | ret = -EINVAL; | |
491 | } | |
492 | ||
493 | return ret; | |
494 | } | |
495 | ||
496 | #define BYTES_TO_BITS(nb) ((BITS_PER_LONG * (nb)) / sizeof(long)) | |
497 | ||
498 | /* Bitfield type needs to be parsed into a fetch function */ | |
499 | static int __parse_bitfield_probe_arg(const char *bf, | |
500 | const struct fetch_type *t, | |
501 | struct fetch_param *f) | |
502 | { | |
503 | struct bitfield_fetch_param *bprm; | |
504 | unsigned long bw, bo; | |
505 | char *tail; | |
506 | ||
507 | if (*bf != 'b') | |
508 | return 0; | |
509 | ||
510 | bprm = kzalloc(sizeof(*bprm), GFP_KERNEL); | |
511 | if (!bprm) | |
512 | return -ENOMEM; | |
513 | ||
514 | bprm->orig = *f; | |
515 | f->fn = t->fetch[FETCH_MTD_bitfield]; | |
516 | f->data = (void *)bprm; | |
517 | bw = simple_strtoul(bf + 1, &tail, 0); /* Use simple one */ | |
518 | ||
519 | if (bw == 0 || *tail != '@') | |
520 | return -EINVAL; | |
521 | ||
522 | bf = tail + 1; | |
523 | bo = simple_strtoul(bf, &tail, 0); | |
524 | ||
525 | if (tail == bf || *tail != '/') | |
526 | return -EINVAL; | |
527 | ||
528 | bprm->hi_shift = BYTES_TO_BITS(t->size) - (bw + bo); | |
529 | bprm->low_shift = bprm->hi_shift + bo; | |
530 | ||
531 | return (BYTES_TO_BITS(t->size) < (bw + bo)) ? -EINVAL : 0; | |
532 | } | |
533 | ||
534 | /* String length checking wrapper */ | |
535 | int traceprobe_parse_probe_arg(char *arg, ssize_t *size, | |
d9a16d3a SR |
536 | struct probe_arg *parg, bool is_return, bool is_kprobe, |
537 | const struct fetch_type *ftbl) | |
8ab83f56 SD |
538 | { |
539 | const char *t; | |
540 | int ret; | |
541 | ||
542 | if (strlen(arg) > MAX_ARGSTR_LEN) { | |
543 | pr_info("Argument is too long.: %s\n", arg); | |
544 | return -ENOSPC; | |
545 | } | |
546 | parg->comm = kstrdup(arg, GFP_KERNEL); | |
547 | if (!parg->comm) { | |
548 | pr_info("Failed to allocate memory for command '%s'.\n", arg); | |
549 | return -ENOMEM; | |
550 | } | |
551 | t = strchr(parg->comm, ':'); | |
552 | if (t) { | |
553 | arg[t - parg->comm] = '\0'; | |
554 | t++; | |
555 | } | |
35abb67d OS |
556 | /* |
557 | * The default type of $comm should be "string", and it can't be | |
558 | * dereferenced. | |
559 | */ | |
560 | if (!t && strcmp(arg, "$comm") == 0) | |
561 | t = "string"; | |
34fee3a1 | 562 | parg->type = find_fetch_type(t, ftbl); |
8ab83f56 SD |
563 | if (!parg->type) { |
564 | pr_info("Unsupported type: %s\n", t); | |
565 | return -EINVAL; | |
566 | } | |
567 | parg->offset = *size; | |
568 | *size += parg->type->size; | |
d9a16d3a SR |
569 | ret = parse_probe_arg(arg, parg->type, &parg->fetch, is_return, |
570 | is_kprobe, ftbl); | |
8ab83f56 SD |
571 | |
572 | if (ret >= 0 && t != NULL) | |
573 | ret = __parse_bitfield_probe_arg(t, parg->type, &parg->fetch); | |
574 | ||
575 | if (ret >= 0) { | |
576 | parg->fetch_size.fn = get_fetch_size_function(parg->type, | |
34fee3a1 NK |
577 | parg->fetch.fn, |
578 | ftbl); | |
8ab83f56 SD |
579 | parg->fetch_size.data = parg->fetch.data; |
580 | } | |
581 | ||
582 | return ret; | |
583 | } | |
584 | ||
585 | /* Return 1 if name is reserved or already used by another argument */ | |
586 | int traceprobe_conflict_field_name(const char *name, | |
587 | struct probe_arg *args, int narg) | |
588 | { | |
589 | int i; | |
590 | ||
591 | for (i = 0; i < ARRAY_SIZE(reserved_field_names); i++) | |
592 | if (strcmp(reserved_field_names[i], name) == 0) | |
593 | return 1; | |
594 | ||
595 | for (i = 0; i < narg; i++) | |
596 | if (strcmp(args[i].name, name) == 0) | |
597 | return 1; | |
598 | ||
599 | return 0; | |
600 | } | |
601 | ||
602 | void traceprobe_update_arg(struct probe_arg *arg) | |
603 | { | |
604 | if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn)) | |
605 | update_bitfield_fetch_param(arg->fetch.data); | |
606 | else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn)) | |
607 | update_deref_fetch_param(arg->fetch.data); | |
608 | else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn)) | |
609 | update_symbol_cache(arg->fetch.data); | |
610 | } | |
611 | ||
612 | void traceprobe_free_probe_arg(struct probe_arg *arg) | |
613 | { | |
614 | if (CHECK_FETCH_FUNCS(bitfield, arg->fetch.fn)) | |
615 | free_bitfield_fetch_param(arg->fetch.data); | |
616 | else if (CHECK_FETCH_FUNCS(deref, arg->fetch.fn)) | |
617 | free_deref_fetch_param(arg->fetch.data); | |
618 | else if (CHECK_FETCH_FUNCS(symbol, arg->fetch.fn)) | |
619 | free_symbol_cache(arg->fetch.data); | |
620 | ||
621 | kfree(arg->name); | |
622 | kfree(arg->comm); | |
623 | } | |
624 | ||
625 | int traceprobe_command(const char *buf, int (*createfn)(int, char **)) | |
626 | { | |
627 | char **argv; | |
628 | int argc, ret; | |
629 | ||
630 | argc = 0; | |
631 | ret = 0; | |
632 | argv = argv_split(GFP_KERNEL, buf, &argc); | |
633 | if (!argv) | |
634 | return -ENOMEM; | |
635 | ||
636 | if (argc) | |
637 | ret = createfn(argc, argv); | |
638 | ||
639 | argv_free(argv); | |
640 | ||
641 | return ret; | |
642 | } | |
643 | ||
644 | #define WRITE_BUFSIZE 4096 | |
645 | ||
646 | ssize_t traceprobe_probes_write(struct file *file, const char __user *buffer, | |
647 | size_t count, loff_t *ppos, | |
648 | int (*createfn)(int, char **)) | |
649 | { | |
650 | char *kbuf, *tmp; | |
651 | int ret = 0; | |
652 | size_t done = 0; | |
653 | size_t size; | |
654 | ||
655 | kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL); | |
656 | if (!kbuf) | |
657 | return -ENOMEM; | |
658 | ||
659 | while (done < count) { | |
660 | size = count - done; | |
661 | ||
662 | if (size >= WRITE_BUFSIZE) | |
663 | size = WRITE_BUFSIZE - 1; | |
664 | ||
665 | if (copy_from_user(kbuf, buffer + done, size)) { | |
666 | ret = -EFAULT; | |
667 | goto out; | |
668 | } | |
669 | kbuf[size] = '\0'; | |
670 | tmp = strchr(kbuf, '\n'); | |
671 | ||
672 | if (tmp) { | |
673 | *tmp = '\0'; | |
674 | size = tmp - kbuf + 1; | |
675 | } else if (done + size < count) { | |
a395d6a7 JP |
676 | pr_warn("Line length is too long: Should be less than %d\n", |
677 | WRITE_BUFSIZE); | |
8ab83f56 SD |
678 | ret = -EINVAL; |
679 | goto out; | |
680 | } | |
681 | done += size; | |
682 | /* Remove comments */ | |
683 | tmp = strchr(kbuf, '#'); | |
684 | ||
685 | if (tmp) | |
686 | *tmp = '\0'; | |
687 | ||
688 | ret = traceprobe_command(kbuf, createfn); | |
689 | if (ret) | |
690 | goto out; | |
691 | } | |
692 | ret = done; | |
693 | ||
694 | out: | |
695 | kfree(kbuf); | |
696 | ||
697 | return ret; | |
698 | } | |
5bf652aa NK |
699 | |
700 | static int __set_print_fmt(struct trace_probe *tp, char *buf, int len, | |
701 | bool is_return) | |
702 | { | |
703 | int i; | |
704 | int pos = 0; | |
705 | ||
706 | const char *fmt, *arg; | |
707 | ||
708 | if (!is_return) { | |
709 | fmt = "(%lx)"; | |
710 | arg = "REC->" FIELD_STRING_IP; | |
711 | } else { | |
712 | fmt = "(%lx <- %lx)"; | |
713 | arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP; | |
714 | } | |
715 | ||
716 | /* When len=0, we just calculate the needed length */ | |
717 | #define LEN_OR_ZERO (len ? len - pos : 0) | |
718 | ||
719 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt); | |
720 | ||
721 | for (i = 0; i < tp->nr_args; i++) { | |
722 | pos += snprintf(buf + pos, LEN_OR_ZERO, " %s=%s", | |
723 | tp->args[i].name, tp->args[i].type->fmt); | |
724 | } | |
725 | ||
726 | pos += snprintf(buf + pos, LEN_OR_ZERO, "\", %s", arg); | |
727 | ||
728 | for (i = 0; i < tp->nr_args; i++) { | |
729 | if (strcmp(tp->args[i].type->name, "string") == 0) | |
730 | pos += snprintf(buf + pos, LEN_OR_ZERO, | |
731 | ", __get_str(%s)", | |
732 | tp->args[i].name); | |
733 | else | |
734 | pos += snprintf(buf + pos, LEN_OR_ZERO, ", REC->%s", | |
735 | tp->args[i].name); | |
736 | } | |
737 | ||
738 | #undef LEN_OR_ZERO | |
739 | ||
740 | /* return the length of print_fmt */ | |
741 | return pos; | |
742 | } | |
743 | ||
744 | int set_print_fmt(struct trace_probe *tp, bool is_return) | |
745 | { | |
746 | int len; | |
747 | char *print_fmt; | |
748 | ||
749 | /* First: called with 0 length to calculate the needed length */ | |
750 | len = __set_print_fmt(tp, NULL, 0, is_return); | |
751 | print_fmt = kmalloc(len + 1, GFP_KERNEL); | |
752 | if (!print_fmt) | |
753 | return -ENOMEM; | |
754 | ||
755 | /* Second: actually write the @print_fmt */ | |
756 | __set_print_fmt(tp, print_fmt, len + 1, is_return); | |
757 | tp->call.print_fmt = print_fmt; | |
758 | ||
759 | return 0; | |
760 | } |