Commit | Line | Data |
---|---|---|
f3f096cf SD |
1 | /* |
2 | * uprobes-based tracing 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 | * Copyright (C) IBM Corporation, 2010-2012 | |
18 | * Author: Srikar Dronamraju <srikar@linux.vnet.ibm.com> | |
19 | */ | |
20 | ||
21 | #include <linux/module.h> | |
22 | #include <linux/uaccess.h> | |
23 | #include <linux/uprobes.h> | |
24 | #include <linux/namei.h> | |
b2e902f0 | 25 | #include <linux/string.h> |
f3f096cf SD |
26 | |
27 | #include "trace_probe.h" | |
28 | ||
29 | #define UPROBE_EVENT_SYSTEM "uprobes" | |
30 | ||
457d1772 ON |
31 | struct uprobe_trace_entry_head { |
32 | struct trace_entry ent; | |
33 | unsigned long vaddr[]; | |
34 | }; | |
35 | ||
36 | #define SIZEOF_TRACE_ENTRY(is_return) \ | |
37 | (sizeof(struct uprobe_trace_entry_head) + \ | |
38 | sizeof(unsigned long) * (is_return ? 2 : 1)) | |
39 | ||
40 | #define DATAOF_TRACE_ENTRY(entry, is_return) \ | |
41 | ((void*)(entry) + SIZEOF_TRACE_ENTRY(is_return)) | |
42 | ||
736288ba ON |
43 | struct trace_uprobe_filter { |
44 | rwlock_t rwlock; | |
45 | int nr_systemwide; | |
46 | struct list_head perf_events; | |
47 | }; | |
48 | ||
f3f096cf SD |
49 | /* |
50 | * uprobe event core functions | |
51 | */ | |
f3f096cf SD |
52 | struct trace_uprobe { |
53 | struct list_head list; | |
736288ba | 54 | struct trace_uprobe_filter filter; |
a932b738 | 55 | struct uprobe_consumer consumer; |
f3f096cf SD |
56 | struct inode *inode; |
57 | char *filename; | |
58 | unsigned long offset; | |
59 | unsigned long nhit; | |
14577c39 | 60 | struct trace_probe tp; |
f3f096cf SD |
61 | }; |
62 | ||
14577c39 NK |
63 | #define SIZEOF_TRACE_UPROBE(n) \ |
64 | (offsetof(struct trace_uprobe, tp.args) + \ | |
f3f096cf SD |
65 | (sizeof(struct probe_arg) * (n))) |
66 | ||
67 | static int register_uprobe_event(struct trace_uprobe *tu); | |
c6c2401d | 68 | static int unregister_uprobe_event(struct trace_uprobe *tu); |
f3f096cf SD |
69 | |
70 | static DEFINE_MUTEX(uprobe_lock); | |
71 | static LIST_HEAD(uprobe_list); | |
72 | ||
b7e0bf34 NK |
73 | struct uprobe_dispatch_data { |
74 | struct trace_uprobe *tu; | |
75 | unsigned long bp_addr; | |
76 | }; | |
77 | ||
f3f096cf | 78 | static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs); |
c1ae5c75 ON |
79 | static int uretprobe_dispatcher(struct uprobe_consumer *con, |
80 | unsigned long func, struct pt_regs *regs); | |
f3f096cf | 81 | |
3fd996a2 NK |
82 | #ifdef CONFIG_STACK_GROWSUP |
83 | static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n) | |
84 | { | |
85 | return addr - (n * sizeof(long)); | |
86 | } | |
87 | #else | |
88 | static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n) | |
89 | { | |
90 | return addr + (n * sizeof(long)); | |
91 | } | |
92 | #endif | |
93 | ||
94 | static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n) | |
95 | { | |
96 | unsigned long ret; | |
97 | unsigned long addr = user_stack_pointer(regs); | |
98 | ||
99 | addr = adjust_stack_addr(addr, n); | |
100 | ||
101 | if (copy_from_user(&ret, (void __force __user *) addr, sizeof(ret))) | |
102 | return 0; | |
103 | ||
104 | return ret; | |
105 | } | |
106 | ||
107 | /* | |
108 | * Uprobes-specific fetch functions | |
109 | */ | |
110 | #define DEFINE_FETCH_stack(type) \ | |
111 | static __kprobes void FETCH_FUNC_NAME(stack, type)(struct pt_regs *regs,\ | |
112 | void *offset, void *dest) \ | |
113 | { \ | |
114 | *(type *)dest = (type)get_user_stack_nth(regs, \ | |
115 | ((unsigned long)offset)); \ | |
116 | } | |
117 | DEFINE_BASIC_FETCH_FUNCS(stack) | |
118 | /* No string on the stack entry */ | |
119 | #define fetch_stack_string NULL | |
120 | #define fetch_stack_string_size NULL | |
121 | ||
5baaa59e NK |
122 | #define DEFINE_FETCH_memory(type) \ |
123 | static __kprobes void FETCH_FUNC_NAME(memory, type)(struct pt_regs *regs,\ | |
124 | void *addr, void *dest) \ | |
125 | { \ | |
126 | type retval; \ | |
127 | void __user *vaddr = (void __force __user *) addr; \ | |
128 | \ | |
129 | if (copy_from_user(&retval, vaddr, sizeof(type))) \ | |
130 | *(type *)dest = 0; \ | |
131 | else \ | |
132 | *(type *) dest = retval; \ | |
133 | } | |
134 | DEFINE_BASIC_FETCH_FUNCS(memory) | |
135 | /* | |
136 | * Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max | |
137 | * length and relative data location. | |
138 | */ | |
139 | static __kprobes void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, | |
140 | void *addr, void *dest) | |
141 | { | |
142 | long ret; | |
143 | u32 rloc = *(u32 *)dest; | |
144 | int maxlen = get_rloc_len(rloc); | |
145 | u8 *dst = get_rloc_data(dest); | |
146 | void __user *src = (void __force __user *) addr; | |
147 | ||
148 | if (!maxlen) | |
149 | return; | |
150 | ||
151 | ret = strncpy_from_user(dst, src, maxlen); | |
152 | ||
153 | if (ret < 0) { /* Failed to fetch string */ | |
154 | ((u8 *)get_rloc_data(dest))[0] = '\0'; | |
155 | *(u32 *)dest = make_data_rloc(0, get_rloc_offs(rloc)); | |
156 | } else { | |
157 | *(u32 *)dest = make_data_rloc(ret, get_rloc_offs(rloc)); | |
158 | } | |
159 | } | |
160 | ||
161 | static __kprobes void FETCH_FUNC_NAME(memory, string_size)(struct pt_regs *regs, | |
162 | void *addr, void *dest) | |
163 | { | |
164 | int len; | |
165 | void __user *vaddr = (void __force __user *) addr; | |
166 | ||
167 | len = strnlen_user(vaddr, MAX_STRING_SIZE); | |
168 | ||
169 | if (len == 0 || len > MAX_STRING_SIZE) /* Failed to check length */ | |
170 | *(u32 *)dest = 0; | |
171 | else | |
172 | *(u32 *)dest = len; | |
173 | } | |
3fd996a2 | 174 | |
b7e0bf34 NK |
175 | static unsigned long translate_user_vaddr(void *file_offset) |
176 | { | |
177 | unsigned long base_addr; | |
178 | struct uprobe_dispatch_data *udd; | |
179 | ||
180 | udd = (void *) current->utask->vaddr; | |
181 | ||
182 | base_addr = udd->bp_addr - udd->tu->offset; | |
183 | return base_addr + (unsigned long)file_offset; | |
184 | } | |
185 | ||
186 | #define DEFINE_FETCH_file_offset(type) \ | |
187 | static __kprobes void FETCH_FUNC_NAME(file_offset, type)(struct pt_regs *regs,\ | |
188 | void *offset, void *dest) \ | |
189 | { \ | |
190 | void *vaddr = (void *)translate_user_vaddr(offset); \ | |
191 | \ | |
192 | FETCH_FUNC_NAME(memory, type)(regs, vaddr, dest); \ | |
193 | } | |
194 | DEFINE_BASIC_FETCH_FUNCS(file_offset) | |
195 | DEFINE_FETCH_file_offset(string) | |
196 | DEFINE_FETCH_file_offset(string_size) | |
197 | ||
34fee3a1 NK |
198 | /* Fetch type information table */ |
199 | const struct fetch_type uprobes_fetch_type_table[] = { | |
200 | /* Special types */ | |
201 | [FETCH_TYPE_STRING] = __ASSIGN_FETCH_TYPE("string", string, string, | |
202 | sizeof(u32), 1, "__data_loc char[]"), | |
203 | [FETCH_TYPE_STRSIZE] = __ASSIGN_FETCH_TYPE("string_size", u32, | |
204 | string_size, sizeof(u32), 0, "u32"), | |
205 | /* Basic types */ | |
206 | ASSIGN_FETCH_TYPE(u8, u8, 0), | |
207 | ASSIGN_FETCH_TYPE(u16, u16, 0), | |
208 | ASSIGN_FETCH_TYPE(u32, u32, 0), | |
209 | ASSIGN_FETCH_TYPE(u64, u64, 0), | |
210 | ASSIGN_FETCH_TYPE(s8, u8, 1), | |
211 | ASSIGN_FETCH_TYPE(s16, u16, 1), | |
212 | ASSIGN_FETCH_TYPE(s32, u32, 1), | |
213 | ASSIGN_FETCH_TYPE(s64, u64, 1), | |
214 | ||
215 | ASSIGN_FETCH_TYPE_END | |
216 | }; | |
217 | ||
736288ba ON |
218 | static inline void init_trace_uprobe_filter(struct trace_uprobe_filter *filter) |
219 | { | |
220 | rwlock_init(&filter->rwlock); | |
221 | filter->nr_systemwide = 0; | |
222 | INIT_LIST_HEAD(&filter->perf_events); | |
223 | } | |
224 | ||
225 | static inline bool uprobe_filter_is_empty(struct trace_uprobe_filter *filter) | |
226 | { | |
227 | return !filter->nr_systemwide && list_empty(&filter->perf_events); | |
228 | } | |
229 | ||
c1ae5c75 ON |
230 | static inline bool is_ret_probe(struct trace_uprobe *tu) |
231 | { | |
232 | return tu->consumer.ret_handler != NULL; | |
233 | } | |
234 | ||
f3f096cf SD |
235 | /* |
236 | * Allocate new trace_uprobe and initialize it (including uprobes). | |
237 | */ | |
238 | static struct trace_uprobe * | |
c1ae5c75 | 239 | alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret) |
f3f096cf SD |
240 | { |
241 | struct trace_uprobe *tu; | |
242 | ||
243 | if (!event || !is_good_name(event)) | |
244 | return ERR_PTR(-EINVAL); | |
245 | ||
246 | if (!group || !is_good_name(group)) | |
247 | return ERR_PTR(-EINVAL); | |
248 | ||
249 | tu = kzalloc(SIZEOF_TRACE_UPROBE(nargs), GFP_KERNEL); | |
250 | if (!tu) | |
251 | return ERR_PTR(-ENOMEM); | |
252 | ||
14577c39 NK |
253 | tu->tp.call.class = &tu->tp.class; |
254 | tu->tp.call.name = kstrdup(event, GFP_KERNEL); | |
255 | if (!tu->tp.call.name) | |
f3f096cf SD |
256 | goto error; |
257 | ||
14577c39 NK |
258 | tu->tp.class.system = kstrdup(group, GFP_KERNEL); |
259 | if (!tu->tp.class.system) | |
f3f096cf SD |
260 | goto error; |
261 | ||
262 | INIT_LIST_HEAD(&tu->list); | |
a932b738 | 263 | tu->consumer.handler = uprobe_dispatcher; |
c1ae5c75 ON |
264 | if (is_ret) |
265 | tu->consumer.ret_handler = uretprobe_dispatcher; | |
736288ba | 266 | init_trace_uprobe_filter(&tu->filter); |
14577c39 | 267 | tu->tp.call.flags |= TRACE_EVENT_FL_USE_CALL_FILTER; |
f3f096cf SD |
268 | return tu; |
269 | ||
270 | error: | |
14577c39 | 271 | kfree(tu->tp.call.name); |
f3f096cf SD |
272 | kfree(tu); |
273 | ||
274 | return ERR_PTR(-ENOMEM); | |
275 | } | |
276 | ||
277 | static void free_trace_uprobe(struct trace_uprobe *tu) | |
278 | { | |
279 | int i; | |
280 | ||
14577c39 NK |
281 | for (i = 0; i < tu->tp.nr_args; i++) |
282 | traceprobe_free_probe_arg(&tu->tp.args[i]); | |
f3f096cf SD |
283 | |
284 | iput(tu->inode); | |
14577c39 NK |
285 | kfree(tu->tp.call.class->system); |
286 | kfree(tu->tp.call.name); | |
f3f096cf SD |
287 | kfree(tu->filename); |
288 | kfree(tu); | |
289 | } | |
290 | ||
291 | static struct trace_uprobe *find_probe_event(const char *event, const char *group) | |
292 | { | |
293 | struct trace_uprobe *tu; | |
294 | ||
295 | list_for_each_entry(tu, &uprobe_list, list) | |
14577c39 NK |
296 | if (strcmp(tu->tp.call.name, event) == 0 && |
297 | strcmp(tu->tp.call.class->system, group) == 0) | |
f3f096cf SD |
298 | return tu; |
299 | ||
300 | return NULL; | |
301 | } | |
302 | ||
303 | /* Unregister a trace_uprobe and probe_event: call with locking uprobe_lock */ | |
c6c2401d | 304 | static int unregister_trace_uprobe(struct trace_uprobe *tu) |
f3f096cf | 305 | { |
c6c2401d SRRH |
306 | int ret; |
307 | ||
308 | ret = unregister_uprobe_event(tu); | |
309 | if (ret) | |
310 | return ret; | |
311 | ||
f3f096cf | 312 | list_del(&tu->list); |
f3f096cf | 313 | free_trace_uprobe(tu); |
c6c2401d | 314 | return 0; |
f3f096cf SD |
315 | } |
316 | ||
317 | /* Register a trace_uprobe and probe_event */ | |
318 | static int register_trace_uprobe(struct trace_uprobe *tu) | |
319 | { | |
14577c39 | 320 | struct trace_uprobe *old_tu; |
f3f096cf SD |
321 | int ret; |
322 | ||
323 | mutex_lock(&uprobe_lock); | |
324 | ||
325 | /* register as an event */ | |
14577c39 NK |
326 | old_tu = find_probe_event(tu->tp.call.name, tu->tp.call.class->system); |
327 | if (old_tu) { | |
f3f096cf | 328 | /* delete old event */ |
14577c39 | 329 | ret = unregister_trace_uprobe(old_tu); |
c6c2401d SRRH |
330 | if (ret) |
331 | goto end; | |
332 | } | |
f3f096cf SD |
333 | |
334 | ret = register_uprobe_event(tu); | |
335 | if (ret) { | |
336 | pr_warning("Failed to register probe event(%d)\n", ret); | |
337 | goto end; | |
338 | } | |
339 | ||
340 | list_add_tail(&tu->list, &uprobe_list); | |
341 | ||
342 | end: | |
343 | mutex_unlock(&uprobe_lock); | |
344 | ||
345 | return ret; | |
346 | } | |
347 | ||
348 | /* | |
349 | * Argument syntax: | |
306cfe20 | 350 | * - Add uprobe: p|r[:[GRP/]EVENT] PATH:OFFSET [FETCHARGS] |
f3f096cf SD |
351 | * |
352 | * - Remove uprobe: -:[GRP/]EVENT | |
353 | */ | |
354 | static int create_trace_uprobe(int argc, char **argv) | |
355 | { | |
356 | struct trace_uprobe *tu; | |
357 | struct inode *inode; | |
358 | char *arg, *event, *group, *filename; | |
359 | char buf[MAX_EVENT_NAME_LEN]; | |
360 | struct path path; | |
361 | unsigned long offset; | |
4ee5a52e | 362 | bool is_delete, is_return; |
f3f096cf SD |
363 | int i, ret; |
364 | ||
365 | inode = NULL; | |
366 | ret = 0; | |
367 | is_delete = false; | |
4ee5a52e | 368 | is_return = false; |
f3f096cf SD |
369 | event = NULL; |
370 | group = NULL; | |
371 | ||
372 | /* argc must be >= 1 */ | |
373 | if (argv[0][0] == '-') | |
374 | is_delete = true; | |
4ee5a52e ON |
375 | else if (argv[0][0] == 'r') |
376 | is_return = true; | |
f3f096cf | 377 | else if (argv[0][0] != 'p') { |
4ee5a52e | 378 | pr_info("Probe definition must be started with 'p', 'r' or '-'.\n"); |
f3f096cf SD |
379 | return -EINVAL; |
380 | } | |
381 | ||
382 | if (argv[0][1] == ':') { | |
383 | event = &argv[0][2]; | |
384 | arg = strchr(event, '/'); | |
385 | ||
386 | if (arg) { | |
387 | group = event; | |
388 | event = arg + 1; | |
389 | event[-1] = '\0'; | |
390 | ||
391 | if (strlen(group) == 0) { | |
392 | pr_info("Group name is not specified\n"); | |
393 | return -EINVAL; | |
394 | } | |
395 | } | |
396 | if (strlen(event) == 0) { | |
397 | pr_info("Event name is not specified\n"); | |
398 | return -EINVAL; | |
399 | } | |
400 | } | |
401 | if (!group) | |
402 | group = UPROBE_EVENT_SYSTEM; | |
403 | ||
404 | if (is_delete) { | |
c6c2401d SRRH |
405 | int ret; |
406 | ||
f3f096cf SD |
407 | if (!event) { |
408 | pr_info("Delete command needs an event name.\n"); | |
409 | return -EINVAL; | |
410 | } | |
411 | mutex_lock(&uprobe_lock); | |
412 | tu = find_probe_event(event, group); | |
413 | ||
414 | if (!tu) { | |
415 | mutex_unlock(&uprobe_lock); | |
416 | pr_info("Event %s/%s doesn't exist.\n", group, event); | |
417 | return -ENOENT; | |
418 | } | |
419 | /* delete an event */ | |
c6c2401d | 420 | ret = unregister_trace_uprobe(tu); |
f3f096cf | 421 | mutex_unlock(&uprobe_lock); |
c6c2401d | 422 | return ret; |
f3f096cf SD |
423 | } |
424 | ||
425 | if (argc < 2) { | |
426 | pr_info("Probe point is not specified.\n"); | |
427 | return -EINVAL; | |
428 | } | |
429 | if (isdigit(argv[1][0])) { | |
430 | pr_info("probe point must be have a filename.\n"); | |
431 | return -EINVAL; | |
432 | } | |
433 | arg = strchr(argv[1], ':'); | |
fa44063f J |
434 | if (!arg) { |
435 | ret = -EINVAL; | |
f3f096cf | 436 | goto fail_address_parse; |
fa44063f | 437 | } |
f3f096cf SD |
438 | |
439 | *arg++ = '\0'; | |
440 | filename = argv[1]; | |
441 | ret = kern_path(filename, LOOKUP_FOLLOW, &path); | |
442 | if (ret) | |
443 | goto fail_address_parse; | |
444 | ||
f3f096cf | 445 | inode = igrab(path.dentry->d_inode); |
84d7ed79 ON |
446 | path_put(&path); |
447 | ||
7e4e28c5 | 448 | if (!inode || !S_ISREG(inode->i_mode)) { |
d24d7dbf JZ |
449 | ret = -EINVAL; |
450 | goto fail_address_parse; | |
451 | } | |
f3f096cf | 452 | |
84d7ed79 ON |
453 | ret = kstrtoul(arg, 0, &offset); |
454 | if (ret) | |
455 | goto fail_address_parse; | |
456 | ||
f3f096cf SD |
457 | argc -= 2; |
458 | argv += 2; | |
459 | ||
460 | /* setup a probe */ | |
461 | if (!event) { | |
b2e902f0 | 462 | char *tail; |
f3f096cf SD |
463 | char *ptr; |
464 | ||
b2e902f0 AS |
465 | tail = kstrdup(kbasename(filename), GFP_KERNEL); |
466 | if (!tail) { | |
f3f096cf SD |
467 | ret = -ENOMEM; |
468 | goto fail_address_parse; | |
469 | } | |
470 | ||
f3f096cf SD |
471 | ptr = strpbrk(tail, ".-_"); |
472 | if (ptr) | |
473 | *ptr = '\0'; | |
474 | ||
475 | snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_0x%lx", 'p', tail, offset); | |
476 | event = buf; | |
477 | kfree(tail); | |
478 | } | |
479 | ||
4ee5a52e | 480 | tu = alloc_trace_uprobe(group, event, argc, is_return); |
f3f096cf SD |
481 | if (IS_ERR(tu)) { |
482 | pr_info("Failed to allocate trace_uprobe.(%d)\n", (int)PTR_ERR(tu)); | |
483 | ret = PTR_ERR(tu); | |
484 | goto fail_address_parse; | |
485 | } | |
486 | tu->offset = offset; | |
487 | tu->inode = inode; | |
488 | tu->filename = kstrdup(filename, GFP_KERNEL); | |
489 | ||
490 | if (!tu->filename) { | |
491 | pr_info("Failed to allocate filename.\n"); | |
492 | ret = -ENOMEM; | |
493 | goto error; | |
494 | } | |
495 | ||
496 | /* parse arguments */ | |
497 | ret = 0; | |
498 | for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { | |
14577c39 NK |
499 | struct probe_arg *parg = &tu->tp.args[i]; |
500 | ||
f3f096cf | 501 | /* Increment count for freeing args in error case */ |
14577c39 | 502 | tu->tp.nr_args++; |
f3f096cf SD |
503 | |
504 | /* Parse argument name */ | |
505 | arg = strchr(argv[i], '='); | |
506 | if (arg) { | |
507 | *arg++ = '\0'; | |
14577c39 | 508 | parg->name = kstrdup(argv[i], GFP_KERNEL); |
f3f096cf SD |
509 | } else { |
510 | arg = argv[i]; | |
511 | /* If argument name is omitted, set "argN" */ | |
512 | snprintf(buf, MAX_EVENT_NAME_LEN, "arg%d", i + 1); | |
14577c39 | 513 | parg->name = kstrdup(buf, GFP_KERNEL); |
f3f096cf SD |
514 | } |
515 | ||
14577c39 | 516 | if (!parg->name) { |
f3f096cf SD |
517 | pr_info("Failed to allocate argument[%d] name.\n", i); |
518 | ret = -ENOMEM; | |
519 | goto error; | |
520 | } | |
521 | ||
14577c39 NK |
522 | if (!is_good_name(parg->name)) { |
523 | pr_info("Invalid argument[%d] name: %s\n", i, parg->name); | |
f3f096cf SD |
524 | ret = -EINVAL; |
525 | goto error; | |
526 | } | |
527 | ||
14577c39 | 528 | if (traceprobe_conflict_field_name(parg->name, tu->tp.args, i)) { |
f3f096cf SD |
529 | pr_info("Argument[%d] name '%s' conflicts with " |
530 | "another field.\n", i, argv[i]); | |
531 | ret = -EINVAL; | |
532 | goto error; | |
533 | } | |
534 | ||
535 | /* Parse fetch argument */ | |
14577c39 | 536 | ret = traceprobe_parse_probe_arg(arg, &tu->tp.size, parg, |
a4734145 | 537 | is_return, false); |
f3f096cf SD |
538 | if (ret) { |
539 | pr_info("Parse error at argument[%d]. (%d)\n", i, ret); | |
540 | goto error; | |
541 | } | |
542 | } | |
543 | ||
544 | ret = register_trace_uprobe(tu); | |
545 | if (ret) | |
546 | goto error; | |
547 | return 0; | |
548 | ||
549 | error: | |
550 | free_trace_uprobe(tu); | |
551 | return ret; | |
552 | ||
553 | fail_address_parse: | |
554 | if (inode) | |
555 | iput(inode); | |
556 | ||
d24d7dbf | 557 | pr_info("Failed to parse address or file.\n"); |
f3f096cf SD |
558 | |
559 | return ret; | |
560 | } | |
561 | ||
c6c2401d | 562 | static int cleanup_all_probes(void) |
f3f096cf SD |
563 | { |
564 | struct trace_uprobe *tu; | |
c6c2401d | 565 | int ret = 0; |
f3f096cf SD |
566 | |
567 | mutex_lock(&uprobe_lock); | |
568 | while (!list_empty(&uprobe_list)) { | |
569 | tu = list_entry(uprobe_list.next, struct trace_uprobe, list); | |
c6c2401d SRRH |
570 | ret = unregister_trace_uprobe(tu); |
571 | if (ret) | |
572 | break; | |
f3f096cf SD |
573 | } |
574 | mutex_unlock(&uprobe_lock); | |
c6c2401d | 575 | return ret; |
f3f096cf SD |
576 | } |
577 | ||
578 | /* Probes listing interfaces */ | |
579 | static void *probes_seq_start(struct seq_file *m, loff_t *pos) | |
580 | { | |
581 | mutex_lock(&uprobe_lock); | |
582 | return seq_list_start(&uprobe_list, *pos); | |
583 | } | |
584 | ||
585 | static void *probes_seq_next(struct seq_file *m, void *v, loff_t *pos) | |
586 | { | |
587 | return seq_list_next(v, &uprobe_list, pos); | |
588 | } | |
589 | ||
590 | static void probes_seq_stop(struct seq_file *m, void *v) | |
591 | { | |
592 | mutex_unlock(&uprobe_lock); | |
593 | } | |
594 | ||
595 | static int probes_seq_show(struct seq_file *m, void *v) | |
596 | { | |
597 | struct trace_uprobe *tu = v; | |
3ede82dd | 598 | char c = is_ret_probe(tu) ? 'r' : 'p'; |
f3f096cf SD |
599 | int i; |
600 | ||
14577c39 | 601 | seq_printf(m, "%c:%s/%s", c, tu->tp.call.class->system, tu->tp.call.name); |
f3f096cf SD |
602 | seq_printf(m, " %s:0x%p", tu->filename, (void *)tu->offset); |
603 | ||
14577c39 NK |
604 | for (i = 0; i < tu->tp.nr_args; i++) |
605 | seq_printf(m, " %s=%s", tu->tp.args[i].name, tu->tp.args[i].comm); | |
f3f096cf SD |
606 | |
607 | seq_printf(m, "\n"); | |
608 | return 0; | |
609 | } | |
610 | ||
611 | static const struct seq_operations probes_seq_op = { | |
612 | .start = probes_seq_start, | |
613 | .next = probes_seq_next, | |
614 | .stop = probes_seq_stop, | |
615 | .show = probes_seq_show | |
616 | }; | |
617 | ||
618 | static int probes_open(struct inode *inode, struct file *file) | |
619 | { | |
c6c2401d SRRH |
620 | int ret; |
621 | ||
622 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { | |
623 | ret = cleanup_all_probes(); | |
624 | if (ret) | |
625 | return ret; | |
626 | } | |
f3f096cf SD |
627 | |
628 | return seq_open(file, &probes_seq_op); | |
629 | } | |
630 | ||
631 | static ssize_t probes_write(struct file *file, const char __user *buffer, | |
632 | size_t count, loff_t *ppos) | |
633 | { | |
634 | return traceprobe_probes_write(file, buffer, count, ppos, create_trace_uprobe); | |
635 | } | |
636 | ||
637 | static const struct file_operations uprobe_events_ops = { | |
638 | .owner = THIS_MODULE, | |
639 | .open = probes_open, | |
640 | .read = seq_read, | |
641 | .llseek = seq_lseek, | |
642 | .release = seq_release, | |
643 | .write = probes_write, | |
644 | }; | |
645 | ||
646 | /* Probes profiling interfaces */ | |
647 | static int probes_profile_seq_show(struct seq_file *m, void *v) | |
648 | { | |
649 | struct trace_uprobe *tu = v; | |
650 | ||
14577c39 | 651 | seq_printf(m, " %s %-44s %15lu\n", tu->filename, tu->tp.call.name, tu->nhit); |
f3f096cf SD |
652 | return 0; |
653 | } | |
654 | ||
655 | static const struct seq_operations profile_seq_op = { | |
656 | .start = probes_seq_start, | |
657 | .next = probes_seq_next, | |
658 | .stop = probes_seq_stop, | |
659 | .show = probes_profile_seq_show | |
660 | }; | |
661 | ||
662 | static int profile_open(struct inode *inode, struct file *file) | |
663 | { | |
664 | return seq_open(file, &profile_seq_op); | |
665 | } | |
666 | ||
667 | static const struct file_operations uprobe_profile_ops = { | |
668 | .owner = THIS_MODULE, | |
669 | .open = profile_open, | |
670 | .read = seq_read, | |
671 | .llseek = seq_lseek, | |
672 | .release = seq_release, | |
673 | }; | |
674 | ||
dcad1a20 NK |
675 | struct uprobe_cpu_buffer { |
676 | struct mutex mutex; | |
677 | void *buf; | |
678 | }; | |
679 | static struct uprobe_cpu_buffer __percpu *uprobe_cpu_buffer; | |
680 | static int uprobe_buffer_refcnt; | |
681 | ||
682 | static int uprobe_buffer_init(void) | |
683 | { | |
684 | int cpu, err_cpu; | |
685 | ||
686 | uprobe_cpu_buffer = alloc_percpu(struct uprobe_cpu_buffer); | |
687 | if (uprobe_cpu_buffer == NULL) | |
688 | return -ENOMEM; | |
689 | ||
690 | for_each_possible_cpu(cpu) { | |
691 | struct page *p = alloc_pages_node(cpu_to_node(cpu), | |
692 | GFP_KERNEL, 0); | |
693 | if (p == NULL) { | |
694 | err_cpu = cpu; | |
695 | goto err; | |
696 | } | |
697 | per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf = page_address(p); | |
698 | mutex_init(&per_cpu_ptr(uprobe_cpu_buffer, cpu)->mutex); | |
699 | } | |
700 | ||
701 | return 0; | |
702 | ||
703 | err: | |
704 | for_each_possible_cpu(cpu) { | |
705 | if (cpu == err_cpu) | |
706 | break; | |
707 | free_page((unsigned long)per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf); | |
708 | } | |
709 | ||
710 | free_percpu(uprobe_cpu_buffer); | |
711 | return -ENOMEM; | |
712 | } | |
713 | ||
714 | static int uprobe_buffer_enable(void) | |
715 | { | |
716 | int ret = 0; | |
717 | ||
718 | BUG_ON(!mutex_is_locked(&event_mutex)); | |
719 | ||
720 | if (uprobe_buffer_refcnt++ == 0) { | |
721 | ret = uprobe_buffer_init(); | |
722 | if (ret < 0) | |
723 | uprobe_buffer_refcnt--; | |
724 | } | |
725 | ||
726 | return ret; | |
727 | } | |
728 | ||
729 | static void uprobe_buffer_disable(void) | |
730 | { | |
731 | BUG_ON(!mutex_is_locked(&event_mutex)); | |
732 | ||
733 | if (--uprobe_buffer_refcnt == 0) { | |
734 | free_percpu(uprobe_cpu_buffer); | |
735 | uprobe_cpu_buffer = NULL; | |
736 | } | |
737 | } | |
738 | ||
739 | static struct uprobe_cpu_buffer *uprobe_buffer_get(void) | |
740 | { | |
741 | struct uprobe_cpu_buffer *ucb; | |
742 | int cpu; | |
743 | ||
744 | cpu = raw_smp_processor_id(); | |
745 | ucb = per_cpu_ptr(uprobe_cpu_buffer, cpu); | |
746 | ||
747 | /* | |
748 | * Use per-cpu buffers for fastest access, but we might migrate | |
749 | * so the mutex makes sure we have sole access to it. | |
750 | */ | |
751 | mutex_lock(&ucb->mutex); | |
752 | ||
753 | return ucb; | |
754 | } | |
755 | ||
756 | static void uprobe_buffer_put(struct uprobe_cpu_buffer *ucb) | |
757 | { | |
758 | mutex_unlock(&ucb->mutex); | |
759 | } | |
760 | ||
a51cc604 ON |
761 | static void uprobe_trace_print(struct trace_uprobe *tu, |
762 | unsigned long func, struct pt_regs *regs) | |
f3f096cf SD |
763 | { |
764 | struct uprobe_trace_entry_head *entry; | |
765 | struct ring_buffer_event *event; | |
766 | struct ring_buffer *buffer; | |
dcad1a20 | 767 | struct uprobe_cpu_buffer *ucb; |
457d1772 | 768 | void *data; |
dcad1a20 | 769 | int size, dsize, esize; |
14577c39 | 770 | struct ftrace_event_call *call = &tu->tp.call; |
f3f096cf | 771 | |
dcad1a20 NK |
772 | dsize = __get_data_size(&tu->tp, regs); |
773 | esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); | |
774 | ||
775 | if (WARN_ON_ONCE(!uprobe_cpu_buffer || tu->tp.size + dsize > PAGE_SIZE)) | |
776 | return; | |
777 | ||
778 | ucb = uprobe_buffer_get(); | |
779 | store_trace_args(esize, &tu->tp, regs, ucb->buf, dsize); | |
780 | ||
781 | size = esize + tu->tp.size + dsize; | |
f3f096cf | 782 | event = trace_current_buffer_lock_reserve(&buffer, call->event.type, |
dcad1a20 | 783 | size, 0, 0); |
f3f096cf | 784 | if (!event) |
dcad1a20 | 785 | goto out; |
f3f096cf SD |
786 | |
787 | entry = ring_buffer_event_data(event); | |
393a736c ON |
788 | if (is_ret_probe(tu)) { |
789 | entry->vaddr[0] = func; | |
790 | entry->vaddr[1] = instruction_pointer(regs); | |
791 | data = DATAOF_TRACE_ENTRY(entry, true); | |
792 | } else { | |
793 | entry->vaddr[0] = instruction_pointer(regs); | |
794 | data = DATAOF_TRACE_ENTRY(entry, false); | |
795 | } | |
796 | ||
dcad1a20 | 797 | memcpy(data, ucb->buf, tu->tp.size + dsize); |
f3f096cf | 798 | |
f306cc82 | 799 | if (!call_filter_check_discard(call, entry, buffer, event)) |
0e3853d2 | 800 | trace_buffer_unlock_commit(buffer, event, 0, 0); |
dcad1a20 NK |
801 | |
802 | out: | |
803 | uprobe_buffer_put(ucb); | |
a51cc604 | 804 | } |
f42d24a1 | 805 | |
a51cc604 ON |
806 | /* uprobe handler */ |
807 | static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs) | |
808 | { | |
393a736c ON |
809 | if (!is_ret_probe(tu)) |
810 | uprobe_trace_print(tu, 0, regs); | |
f42d24a1 | 811 | return 0; |
f3f096cf SD |
812 | } |
813 | ||
c1ae5c75 ON |
814 | static void uretprobe_trace_func(struct trace_uprobe *tu, unsigned long func, |
815 | struct pt_regs *regs) | |
816 | { | |
817 | uprobe_trace_print(tu, func, regs); | |
818 | } | |
819 | ||
f3f096cf SD |
820 | /* Event entry printers */ |
821 | static enum print_line_t | |
822 | print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *event) | |
823 | { | |
457d1772 | 824 | struct uprobe_trace_entry_head *entry; |
f3f096cf SD |
825 | struct trace_seq *s = &iter->seq; |
826 | struct trace_uprobe *tu; | |
827 | u8 *data; | |
828 | int i; | |
829 | ||
457d1772 | 830 | entry = (struct uprobe_trace_entry_head *)iter->ent; |
14577c39 | 831 | tu = container_of(event, struct trace_uprobe, tp.call.event); |
f3f096cf | 832 | |
3ede82dd | 833 | if (is_ret_probe(tu)) { |
14577c39 | 834 | if (!trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)", tu->tp.call.name, |
3ede82dd ON |
835 | entry->vaddr[1], entry->vaddr[0])) |
836 | goto partial; | |
837 | data = DATAOF_TRACE_ENTRY(entry, true); | |
838 | } else { | |
14577c39 | 839 | if (!trace_seq_printf(s, "%s: (0x%lx)", tu->tp.call.name, |
3ede82dd ON |
840 | entry->vaddr[0])) |
841 | goto partial; | |
842 | data = DATAOF_TRACE_ENTRY(entry, false); | |
843 | } | |
f3f096cf | 844 | |
14577c39 NK |
845 | for (i = 0; i < tu->tp.nr_args; i++) { |
846 | struct probe_arg *parg = &tu->tp.args[i]; | |
847 | ||
848 | if (!parg->type->print(s, parg->name, data + parg->offset, entry)) | |
f3f096cf SD |
849 | goto partial; |
850 | } | |
851 | ||
852 | if (trace_seq_puts(s, "\n")) | |
853 | return TRACE_TYPE_HANDLED; | |
854 | ||
855 | partial: | |
856 | return TRACE_TYPE_PARTIAL_LINE; | |
857 | } | |
858 | ||
31ba3348 ON |
859 | typedef bool (*filter_func_t)(struct uprobe_consumer *self, |
860 | enum uprobe_filter_ctx ctx, | |
861 | struct mm_struct *mm); | |
862 | ||
863 | static int | |
864 | probe_event_enable(struct trace_uprobe *tu, int flag, filter_func_t filter) | |
f3f096cf | 865 | { |
f3f096cf SD |
866 | int ret = 0; |
867 | ||
14577c39 | 868 | if (trace_probe_is_enabled(&tu->tp)) |
f3f096cf SD |
869 | return -EINTR; |
870 | ||
dcad1a20 NK |
871 | ret = uprobe_buffer_enable(); |
872 | if (ret < 0) | |
873 | return ret; | |
874 | ||
736288ba ON |
875 | WARN_ON(!uprobe_filter_is_empty(&tu->filter)); |
876 | ||
14577c39 | 877 | tu->tp.flags |= flag; |
31ba3348 | 878 | tu->consumer.filter = filter; |
a932b738 ON |
879 | ret = uprobe_register(tu->inode, tu->offset, &tu->consumer); |
880 | if (ret) | |
14577c39 | 881 | tu->tp.flags &= ~flag; |
f3f096cf | 882 | |
4161824f | 883 | return ret; |
f3f096cf SD |
884 | } |
885 | ||
886 | static void probe_event_disable(struct trace_uprobe *tu, int flag) | |
887 | { | |
14577c39 | 888 | if (!trace_probe_is_enabled(&tu->tp)) |
f3f096cf SD |
889 | return; |
890 | ||
736288ba ON |
891 | WARN_ON(!uprobe_filter_is_empty(&tu->filter)); |
892 | ||
a932b738 | 893 | uprobe_unregister(tu->inode, tu->offset, &tu->consumer); |
14577c39 | 894 | tu->tp.flags &= ~flag; |
dcad1a20 NK |
895 | |
896 | uprobe_buffer_disable(); | |
f3f096cf SD |
897 | } |
898 | ||
899 | static int uprobe_event_define_fields(struct ftrace_event_call *event_call) | |
900 | { | |
457d1772 | 901 | int ret, i, size; |
f3f096cf | 902 | struct uprobe_trace_entry_head field; |
457d1772 | 903 | struct trace_uprobe *tu = event_call->data; |
f3f096cf | 904 | |
4d1298e2 ON |
905 | if (is_ret_probe(tu)) { |
906 | DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_FUNC, 0); | |
907 | DEFINE_FIELD(unsigned long, vaddr[1], FIELD_STRING_RETIP, 0); | |
908 | size = SIZEOF_TRACE_ENTRY(true); | |
909 | } else { | |
910 | DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_IP, 0); | |
911 | size = SIZEOF_TRACE_ENTRY(false); | |
912 | } | |
f3f096cf | 913 | /* Set argument names as fields */ |
14577c39 NK |
914 | for (i = 0; i < tu->tp.nr_args; i++) { |
915 | struct probe_arg *parg = &tu->tp.args[i]; | |
916 | ||
917 | ret = trace_define_field(event_call, parg->type->fmttype, | |
918 | parg->name, size + parg->offset, | |
919 | parg->type->size, parg->type->is_signed, | |
f3f096cf SD |
920 | FILTER_OTHER); |
921 | ||
922 | if (ret) | |
923 | return ret; | |
924 | } | |
925 | return 0; | |
926 | } | |
927 | ||
f3f096cf | 928 | #ifdef CONFIG_PERF_EVENTS |
31ba3348 ON |
929 | static bool |
930 | __uprobe_perf_filter(struct trace_uprobe_filter *filter, struct mm_struct *mm) | |
931 | { | |
932 | struct perf_event *event; | |
933 | ||
934 | if (filter->nr_systemwide) | |
935 | return true; | |
936 | ||
937 | list_for_each_entry(event, &filter->perf_events, hw.tp_list) { | |
938 | if (event->hw.tp_target->mm == mm) | |
939 | return true; | |
940 | } | |
941 | ||
942 | return false; | |
943 | } | |
944 | ||
b2fe8ba6 ON |
945 | static inline bool |
946 | uprobe_filter_event(struct trace_uprobe *tu, struct perf_event *event) | |
947 | { | |
948 | return __uprobe_perf_filter(&tu->filter, event->hw.tp_target->mm); | |
949 | } | |
950 | ||
736288ba ON |
951 | static int uprobe_perf_open(struct trace_uprobe *tu, struct perf_event *event) |
952 | { | |
b2fe8ba6 ON |
953 | bool done; |
954 | ||
736288ba | 955 | write_lock(&tu->filter.rwlock); |
b2fe8ba6 ON |
956 | if (event->hw.tp_target) { |
957 | /* | |
958 | * event->parent != NULL means copy_process(), we can avoid | |
959 | * uprobe_apply(). current->mm must be probed and we can rely | |
960 | * on dup_mmap() which preserves the already installed bp's. | |
961 | * | |
962 | * attr.enable_on_exec means that exec/mmap will install the | |
963 | * breakpoints we need. | |
964 | */ | |
965 | done = tu->filter.nr_systemwide || | |
966 | event->parent || event->attr.enable_on_exec || | |
967 | uprobe_filter_event(tu, event); | |
736288ba | 968 | list_add(&event->hw.tp_list, &tu->filter.perf_events); |
b2fe8ba6 ON |
969 | } else { |
970 | done = tu->filter.nr_systemwide; | |
736288ba | 971 | tu->filter.nr_systemwide++; |
b2fe8ba6 | 972 | } |
736288ba ON |
973 | write_unlock(&tu->filter.rwlock); |
974 | ||
b2fe8ba6 ON |
975 | if (!done) |
976 | uprobe_apply(tu->inode, tu->offset, &tu->consumer, true); | |
31ba3348 | 977 | |
736288ba ON |
978 | return 0; |
979 | } | |
980 | ||
981 | static int uprobe_perf_close(struct trace_uprobe *tu, struct perf_event *event) | |
982 | { | |
b2fe8ba6 ON |
983 | bool done; |
984 | ||
736288ba | 985 | write_lock(&tu->filter.rwlock); |
b2fe8ba6 | 986 | if (event->hw.tp_target) { |
736288ba | 987 | list_del(&event->hw.tp_list); |
b2fe8ba6 ON |
988 | done = tu->filter.nr_systemwide || |
989 | (event->hw.tp_target->flags & PF_EXITING) || | |
990 | uprobe_filter_event(tu, event); | |
991 | } else { | |
736288ba | 992 | tu->filter.nr_systemwide--; |
b2fe8ba6 ON |
993 | done = tu->filter.nr_systemwide; |
994 | } | |
736288ba ON |
995 | write_unlock(&tu->filter.rwlock); |
996 | ||
b2fe8ba6 ON |
997 | if (!done) |
998 | uprobe_apply(tu->inode, tu->offset, &tu->consumer, false); | |
31ba3348 | 999 | |
736288ba ON |
1000 | return 0; |
1001 | } | |
1002 | ||
31ba3348 ON |
1003 | static bool uprobe_perf_filter(struct uprobe_consumer *uc, |
1004 | enum uprobe_filter_ctx ctx, struct mm_struct *mm) | |
1005 | { | |
1006 | struct trace_uprobe *tu; | |
1007 | int ret; | |
1008 | ||
1009 | tu = container_of(uc, struct trace_uprobe, consumer); | |
1010 | read_lock(&tu->filter.rwlock); | |
1011 | ret = __uprobe_perf_filter(&tu->filter, mm); | |
1012 | read_unlock(&tu->filter.rwlock); | |
1013 | ||
1014 | return ret; | |
1015 | } | |
1016 | ||
a51cc604 ON |
1017 | static void uprobe_perf_print(struct trace_uprobe *tu, |
1018 | unsigned long func, struct pt_regs *regs) | |
f3f096cf | 1019 | { |
14577c39 | 1020 | struct ftrace_event_call *call = &tu->tp.call; |
f3f096cf SD |
1021 | struct uprobe_trace_entry_head *entry; |
1022 | struct hlist_head *head; | |
dcad1a20 | 1023 | struct uprobe_cpu_buffer *ucb; |
457d1772 | 1024 | void *data; |
dcad1a20 NK |
1025 | int size, dsize, esize; |
1026 | int rctx; | |
1027 | ||
1028 | dsize = __get_data_size(&tu->tp, regs); | |
1029 | esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu)); | |
f3f096cf | 1030 | |
dcad1a20 NK |
1031 | if (WARN_ON_ONCE(!uprobe_cpu_buffer)) |
1032 | return; | |
1033 | ||
1034 | size = esize + tu->tp.size + dsize; | |
1035 | size = ALIGN(size + sizeof(u32), sizeof(u64)) - sizeof(u32); | |
1036 | if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough")) | |
1037 | return; | |
1038 | ||
1039 | ucb = uprobe_buffer_get(); | |
1040 | store_trace_args(esize, &tu->tp, regs, ucb->buf, dsize); | |
f3f096cf SD |
1041 | |
1042 | preempt_disable(); | |
515619f2 ON |
1043 | head = this_cpu_ptr(call->perf_events); |
1044 | if (hlist_empty(head)) | |
1045 | goto out; | |
1046 | ||
f3f096cf SD |
1047 | entry = perf_trace_buf_prepare(size, call->event.type, regs, &rctx); |
1048 | if (!entry) | |
1049 | goto out; | |
1050 | ||
393a736c ON |
1051 | if (is_ret_probe(tu)) { |
1052 | entry->vaddr[0] = func; | |
32520b2c | 1053 | entry->vaddr[1] = instruction_pointer(regs); |
393a736c ON |
1054 | data = DATAOF_TRACE_ENTRY(entry, true); |
1055 | } else { | |
32520b2c | 1056 | entry->vaddr[0] = instruction_pointer(regs); |
393a736c ON |
1057 | data = DATAOF_TRACE_ENTRY(entry, false); |
1058 | } | |
1059 | ||
dcad1a20 NK |
1060 | memcpy(data, ucb->buf, tu->tp.size + dsize); |
1061 | ||
1062 | if (size - esize > tu->tp.size + dsize) { | |
1063 | int len = tu->tp.size + dsize; | |
14577c39 | 1064 | |
dcad1a20 | 1065 | memset(data + len, 0, size - esize - len); |
14577c39 | 1066 | } |
f3f096cf | 1067 | |
32520b2c | 1068 | perf_trace_buf_submit(entry, size, rctx, 0, 1, regs, head, NULL); |
f3f096cf SD |
1069 | out: |
1070 | preempt_enable(); | |
dcad1a20 | 1071 | uprobe_buffer_put(ucb); |
a51cc604 ON |
1072 | } |
1073 | ||
1074 | /* uprobe profile handler */ | |
1075 | static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs) | |
1076 | { | |
1077 | if (!uprobe_perf_filter(&tu->consumer, 0, current->mm)) | |
1078 | return UPROBE_HANDLER_REMOVE; | |
1079 | ||
393a736c ON |
1080 | if (!is_ret_probe(tu)) |
1081 | uprobe_perf_print(tu, 0, regs); | |
f42d24a1 | 1082 | return 0; |
f3f096cf | 1083 | } |
c1ae5c75 ON |
1084 | |
1085 | static void uretprobe_perf_func(struct trace_uprobe *tu, unsigned long func, | |
1086 | struct pt_regs *regs) | |
1087 | { | |
1088 | uprobe_perf_print(tu, func, regs); | |
1089 | } | |
f3f096cf SD |
1090 | #endif /* CONFIG_PERF_EVENTS */ |
1091 | ||
1092 | static | |
1093 | int trace_uprobe_register(struct ftrace_event_call *event, enum trace_reg type, void *data) | |
1094 | { | |
457d1772 | 1095 | struct trace_uprobe *tu = event->data; |
f3f096cf SD |
1096 | |
1097 | switch (type) { | |
1098 | case TRACE_REG_REGISTER: | |
31ba3348 | 1099 | return probe_event_enable(tu, TP_FLAG_TRACE, NULL); |
f3f096cf SD |
1100 | |
1101 | case TRACE_REG_UNREGISTER: | |
1102 | probe_event_disable(tu, TP_FLAG_TRACE); | |
1103 | return 0; | |
1104 | ||
1105 | #ifdef CONFIG_PERF_EVENTS | |
1106 | case TRACE_REG_PERF_REGISTER: | |
31ba3348 | 1107 | return probe_event_enable(tu, TP_FLAG_PROFILE, uprobe_perf_filter); |
f3f096cf SD |
1108 | |
1109 | case TRACE_REG_PERF_UNREGISTER: | |
1110 | probe_event_disable(tu, TP_FLAG_PROFILE); | |
1111 | return 0; | |
736288ba ON |
1112 | |
1113 | case TRACE_REG_PERF_OPEN: | |
1114 | return uprobe_perf_open(tu, data); | |
1115 | ||
1116 | case TRACE_REG_PERF_CLOSE: | |
1117 | return uprobe_perf_close(tu, data); | |
1118 | ||
f3f096cf SD |
1119 | #endif |
1120 | default: | |
1121 | return 0; | |
1122 | } | |
1123 | return 0; | |
1124 | } | |
1125 | ||
1126 | static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs) | |
1127 | { | |
f3f096cf | 1128 | struct trace_uprobe *tu; |
b7e0bf34 | 1129 | struct uprobe_dispatch_data udd; |
f42d24a1 | 1130 | int ret = 0; |
f3f096cf | 1131 | |
a932b738 | 1132 | tu = container_of(con, struct trace_uprobe, consumer); |
1b47aefd | 1133 | tu->nhit++; |
f3f096cf | 1134 | |
b7e0bf34 NK |
1135 | udd.tu = tu; |
1136 | udd.bp_addr = instruction_pointer(regs); | |
1137 | ||
1138 | current->utask->vaddr = (unsigned long) &udd; | |
1139 | ||
14577c39 | 1140 | if (tu->tp.flags & TP_FLAG_TRACE) |
f42d24a1 | 1141 | ret |= uprobe_trace_func(tu, regs); |
f3f096cf SD |
1142 | |
1143 | #ifdef CONFIG_PERF_EVENTS | |
14577c39 | 1144 | if (tu->tp.flags & TP_FLAG_PROFILE) |
f42d24a1 | 1145 | ret |= uprobe_perf_func(tu, regs); |
f3f096cf | 1146 | #endif |
f42d24a1 | 1147 | return ret; |
f3f096cf SD |
1148 | } |
1149 | ||
c1ae5c75 ON |
1150 | static int uretprobe_dispatcher(struct uprobe_consumer *con, |
1151 | unsigned long func, struct pt_regs *regs) | |
1152 | { | |
1153 | struct trace_uprobe *tu; | |
b7e0bf34 | 1154 | struct uprobe_dispatch_data udd; |
c1ae5c75 ON |
1155 | |
1156 | tu = container_of(con, struct trace_uprobe, consumer); | |
1157 | ||
b7e0bf34 NK |
1158 | udd.tu = tu; |
1159 | udd.bp_addr = func; | |
1160 | ||
1161 | current->utask->vaddr = (unsigned long) &udd; | |
1162 | ||
14577c39 | 1163 | if (tu->tp.flags & TP_FLAG_TRACE) |
c1ae5c75 ON |
1164 | uretprobe_trace_func(tu, func, regs); |
1165 | ||
1166 | #ifdef CONFIG_PERF_EVENTS | |
14577c39 | 1167 | if (tu->tp.flags & TP_FLAG_PROFILE) |
c1ae5c75 ON |
1168 | uretprobe_perf_func(tu, func, regs); |
1169 | #endif | |
1170 | return 0; | |
1171 | } | |
1172 | ||
f3f096cf SD |
1173 | static struct trace_event_functions uprobe_funcs = { |
1174 | .trace = print_uprobe_event | |
1175 | }; | |
1176 | ||
1177 | static int register_uprobe_event(struct trace_uprobe *tu) | |
1178 | { | |
14577c39 | 1179 | struct ftrace_event_call *call = &tu->tp.call; |
f3f096cf SD |
1180 | int ret; |
1181 | ||
1182 | /* Initialize ftrace_event_call */ | |
1183 | INIT_LIST_HEAD(&call->class->fields); | |
1184 | call->event.funcs = &uprobe_funcs; | |
1185 | call->class->define_fields = uprobe_event_define_fields; | |
1186 | ||
5bf652aa | 1187 | if (set_print_fmt(&tu->tp, is_ret_probe(tu)) < 0) |
f3f096cf SD |
1188 | return -ENOMEM; |
1189 | ||
1190 | ret = register_ftrace_event(&call->event); | |
1191 | if (!ret) { | |
1192 | kfree(call->print_fmt); | |
1193 | return -ENODEV; | |
1194 | } | |
1195 | call->flags = 0; | |
1196 | call->class->reg = trace_uprobe_register; | |
1197 | call->data = tu; | |
1198 | ret = trace_add_event_call(call); | |
1199 | ||
1200 | if (ret) { | |
1201 | pr_info("Failed to register uprobe event: %s\n", call->name); | |
1202 | kfree(call->print_fmt); | |
1203 | unregister_ftrace_event(&call->event); | |
1204 | } | |
1205 | ||
1206 | return ret; | |
1207 | } | |
1208 | ||
c6c2401d | 1209 | static int unregister_uprobe_event(struct trace_uprobe *tu) |
f3f096cf | 1210 | { |
c6c2401d SRRH |
1211 | int ret; |
1212 | ||
f3f096cf | 1213 | /* tu->event is unregistered in trace_remove_event_call() */ |
14577c39 | 1214 | ret = trace_remove_event_call(&tu->tp.call); |
c6c2401d SRRH |
1215 | if (ret) |
1216 | return ret; | |
14577c39 NK |
1217 | kfree(tu->tp.call.print_fmt); |
1218 | tu->tp.call.print_fmt = NULL; | |
c6c2401d | 1219 | return 0; |
f3f096cf SD |
1220 | } |
1221 | ||
1222 | /* Make a trace interface for controling probe points */ | |
1223 | static __init int init_uprobe_trace(void) | |
1224 | { | |
1225 | struct dentry *d_tracer; | |
1226 | ||
1227 | d_tracer = tracing_init_dentry(); | |
1228 | if (!d_tracer) | |
1229 | return 0; | |
1230 | ||
1231 | trace_create_file("uprobe_events", 0644, d_tracer, | |
1232 | NULL, &uprobe_events_ops); | |
1233 | /* Profile interface */ | |
1234 | trace_create_file("uprobe_profile", 0444, d_tracer, | |
1235 | NULL, &uprobe_profile_ops); | |
1236 | return 0; | |
1237 | } | |
1238 | ||
1239 | fs_initcall(init_uprobe_trace); |