1
2
3
4
5
6
7
8#define pr_fmt(fmt) "trace_uprobe: " fmt
9
10#include <linux/security.h>
11#include <linux/ctype.h>
12#include <linux/module.h>
13#include <linux/uaccess.h>
14#include <linux/uprobes.h>
15#include <linux/namei.h>
16#include <linux/string.h>
17#include <linux/rculist.h>
18
19#include "trace_dynevent.h"
20#include "trace_probe.h"
21#include "trace_probe_tmpl.h"
22
23#define UPROBE_EVENT_SYSTEM "uprobes"
24
25struct uprobe_trace_entry_head {
26 struct trace_entry ent;
27 unsigned long vaddr[];
28};
29
30#define SIZEOF_TRACE_ENTRY(is_return) \
31 (sizeof(struct uprobe_trace_entry_head) + \
32 sizeof(unsigned long) * (is_return ? 2 : 1))
33
34#define DATAOF_TRACE_ENTRY(entry, is_return) \
35 ((void*)(entry) + SIZEOF_TRACE_ENTRY(is_return))
36
37static int trace_uprobe_create(const char *raw_command);
38static int trace_uprobe_show(struct seq_file *m, struct dyn_event *ev);
39static int trace_uprobe_release(struct dyn_event *ev);
40static bool trace_uprobe_is_busy(struct dyn_event *ev);
41static bool trace_uprobe_match(const char *system, const char *event,
42 int argc, const char **argv, struct dyn_event *ev);
43
44static struct dyn_event_operations trace_uprobe_ops = {
45 .create = trace_uprobe_create,
46 .show = trace_uprobe_show,
47 .is_busy = trace_uprobe_is_busy,
48 .free = trace_uprobe_release,
49 .match = trace_uprobe_match,
50};
51
52
53
54
55struct trace_uprobe {
56 struct dyn_event devent;
57 struct uprobe_consumer consumer;
58 struct path path;
59 struct inode *inode;
60 char *filename;
61 unsigned long offset;
62 unsigned long ref_ctr_offset;
63 unsigned long nhit;
64 struct trace_probe tp;
65};
66
67static bool is_trace_uprobe(struct dyn_event *ev)
68{
69 return ev->ops == &trace_uprobe_ops;
70}
71
72static struct trace_uprobe *to_trace_uprobe(struct dyn_event *ev)
73{
74 return container_of(ev, struct trace_uprobe, devent);
75}
76
77
78
79
80
81
82#define for_each_trace_uprobe(pos, dpos) \
83 for_each_dyn_event(dpos) \
84 if (is_trace_uprobe(dpos) && (pos = to_trace_uprobe(dpos)))
85
86#define SIZEOF_TRACE_UPROBE(n) \
87 (offsetof(struct trace_uprobe, tp.args) + \
88 (sizeof(struct probe_arg) * (n)))
89
90static int register_uprobe_event(struct trace_uprobe *tu);
91static int unregister_uprobe_event(struct trace_uprobe *tu);
92
93struct uprobe_dispatch_data {
94 struct trace_uprobe *tu;
95 unsigned long bp_addr;
96};
97
98static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs);
99static int uretprobe_dispatcher(struct uprobe_consumer *con,
100 unsigned long func, struct pt_regs *regs);
101
102#ifdef CONFIG_STACK_GROWSUP
103static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n)
104{
105 return addr - (n * sizeof(long));
106}
107#else
108static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n)
109{
110 return addr + (n * sizeof(long));
111}
112#endif
113
114static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n)
115{
116 unsigned long ret;
117 unsigned long addr = user_stack_pointer(regs);
118
119 addr = adjust_stack_addr(addr, n);
120
121 if (copy_from_user(&ret, (void __force __user *) addr, sizeof(ret)))
122 return 0;
123
124 return ret;
125}
126
127
128
129
130static nokprobe_inline int
131probe_mem_read(void *dest, void *src, size_t size)
132{
133 void __user *vaddr = (void __force __user *)src;
134
135 return copy_from_user(dest, vaddr, size) ? -EFAULT : 0;
136}
137
138static nokprobe_inline int
139probe_mem_read_user(void *dest, void *src, size_t size)
140{
141 return probe_mem_read(dest, src, size);
142}
143
144
145
146
147
148static nokprobe_inline int
149fetch_store_string(unsigned long addr, void *dest, void *base)
150{
151 long ret;
152 u32 loc = *(u32 *)dest;
153 int maxlen = get_loc_len(loc);
154 u8 *dst = get_loc_data(dest, base);
155 void __user *src = (void __force __user *) addr;
156
157 if (unlikely(!maxlen))
158 return -ENOMEM;
159
160 if (addr == FETCH_TOKEN_COMM)
161 ret = strlcpy(dst, current->comm, maxlen);
162 else
163 ret = strncpy_from_user(dst, src, maxlen);
164 if (ret >= 0) {
165 if (ret == maxlen)
166 dst[ret - 1] = '\0';
167 else
168
169
170
171
172
173 ret++;
174 *(u32 *)dest = make_data_loc(ret, (void *)dst - base);
175 }
176
177 return ret;
178}
179
180static nokprobe_inline int
181fetch_store_string_user(unsigned long addr, void *dest, void *base)
182{
183 return fetch_store_string(addr, dest, base);
184}
185
186
187static nokprobe_inline int
188fetch_store_strlen(unsigned long addr)
189{
190 int len;
191 void __user *vaddr = (void __force __user *) addr;
192
193 if (addr == FETCH_TOKEN_COMM)
194 len = strlen(current->comm) + 1;
195 else
196 len = strnlen_user(vaddr, MAX_STRING_SIZE);
197
198 return (len > MAX_STRING_SIZE) ? 0 : len;
199}
200
201static nokprobe_inline int
202fetch_store_strlen_user(unsigned long addr)
203{
204 return fetch_store_strlen(addr);
205}
206
207static unsigned long translate_user_vaddr(unsigned long file_offset)
208{
209 unsigned long base_addr;
210 struct uprobe_dispatch_data *udd;
211
212 udd = (void *) current->utask->vaddr;
213
214 base_addr = udd->bp_addr - udd->tu->offset;
215 return base_addr + file_offset;
216}
217
218
219static int
220process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest,
221 void *base)
222{
223 unsigned long val;
224
225
226 switch (code->op) {
227 case FETCH_OP_REG:
228 val = regs_get_register(regs, code->param);
229 break;
230 case FETCH_OP_STACK:
231 val = get_user_stack_nth(regs, code->param);
232 break;
233 case FETCH_OP_STACKP:
234 val = user_stack_pointer(regs);
235 break;
236 case FETCH_OP_RETVAL:
237 val = regs_return_value(regs);
238 break;
239 case FETCH_OP_IMM:
240 val = code->immediate;
241 break;
242 case FETCH_OP_COMM:
243 val = FETCH_TOKEN_COMM;
244 break;
245 case FETCH_OP_DATA:
246 val = (unsigned long)code->data;
247 break;
248 case FETCH_OP_FOFFS:
249 val = translate_user_vaddr(code->immediate);
250 break;
251 default:
252 return -EILSEQ;
253 }
254 code++;
255
256 return process_fetch_insn_bottom(code, val, dest, base);
257}
258NOKPROBE_SYMBOL(process_fetch_insn)
259
260static inline void init_trace_uprobe_filter(struct trace_uprobe_filter *filter)
261{
262 rwlock_init(&filter->rwlock);
263 filter->nr_systemwide = 0;
264 INIT_LIST_HEAD(&filter->perf_events);
265}
266
267static inline bool uprobe_filter_is_empty(struct trace_uprobe_filter *filter)
268{
269 return !filter->nr_systemwide && list_empty(&filter->perf_events);
270}
271
272static inline bool is_ret_probe(struct trace_uprobe *tu)
273{
274 return tu->consumer.ret_handler != NULL;
275}
276
277static bool trace_uprobe_is_busy(struct dyn_event *ev)
278{
279 struct trace_uprobe *tu = to_trace_uprobe(ev);
280
281 return trace_probe_is_enabled(&tu->tp);
282}
283
284static bool trace_uprobe_match_command_head(struct trace_uprobe *tu,
285 int argc, const char **argv)
286{
287 char buf[MAX_ARGSTR_LEN + 1];
288 int len;
289
290 if (!argc)
291 return true;
292
293 len = strlen(tu->filename);
294 if (strncmp(tu->filename, argv[0], len) || argv[0][len] != ':')
295 return false;
296
297 if (tu->ref_ctr_offset == 0)
298 snprintf(buf, sizeof(buf), "0x%0*lx",
299 (int)(sizeof(void *) * 2), tu->offset);
300 else
301 snprintf(buf, sizeof(buf), "0x%0*lx(0x%lx)",
302 (int)(sizeof(void *) * 2), tu->offset,
303 tu->ref_ctr_offset);
304 if (strcmp(buf, &argv[0][len + 1]))
305 return false;
306
307 argc--; argv++;
308
309 return trace_probe_match_command_args(&tu->tp, argc, argv);
310}
311
312static bool trace_uprobe_match(const char *system, const char *event,
313 int argc, const char **argv, struct dyn_event *ev)
314{
315 struct trace_uprobe *tu = to_trace_uprobe(ev);
316
317 return strcmp(trace_probe_name(&tu->tp), event) == 0 &&
318 (!system || strcmp(trace_probe_group_name(&tu->tp), system) == 0) &&
319 trace_uprobe_match_command_head(tu, argc, argv);
320}
321
322static nokprobe_inline struct trace_uprobe *
323trace_uprobe_primary_from_call(struct trace_event_call *call)
324{
325 struct trace_probe *tp;
326
327 tp = trace_probe_primary_from_call(call);
328 if (WARN_ON_ONCE(!tp))
329 return NULL;
330
331 return container_of(tp, struct trace_uprobe, tp);
332}
333
334
335
336
337static struct trace_uprobe *
338alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret)
339{
340 struct trace_uprobe *tu;
341 int ret;
342
343 tu = kzalloc(SIZEOF_TRACE_UPROBE(nargs), GFP_KERNEL);
344 if (!tu)
345 return ERR_PTR(-ENOMEM);
346
347 ret = trace_probe_init(&tu->tp, event, group, true);
348 if (ret < 0)
349 goto error;
350
351 dyn_event_init(&tu->devent, &trace_uprobe_ops);
352 tu->consumer.handler = uprobe_dispatcher;
353 if (is_ret)
354 tu->consumer.ret_handler = uretprobe_dispatcher;
355 init_trace_uprobe_filter(tu->tp.event->filter);
356 return tu;
357
358error:
359 kfree(tu);
360
361 return ERR_PTR(ret);
362}
363
364static void free_trace_uprobe(struct trace_uprobe *tu)
365{
366 if (!tu)
367 return;
368
369 path_put(&tu->path);
370 trace_probe_cleanup(&tu->tp);
371 kfree(tu->filename);
372 kfree(tu);
373}
374
375static struct trace_uprobe *find_probe_event(const char *event, const char *group)
376{
377 struct dyn_event *pos;
378 struct trace_uprobe *tu;
379
380 for_each_trace_uprobe(tu, pos)
381 if (strcmp(trace_probe_name(&tu->tp), event) == 0 &&
382 strcmp(trace_probe_group_name(&tu->tp), group) == 0)
383 return tu;
384
385 return NULL;
386}
387
388
389static int unregister_trace_uprobe(struct trace_uprobe *tu)
390{
391 int ret;
392
393 if (trace_probe_has_sibling(&tu->tp))
394 goto unreg;
395
396 ret = unregister_uprobe_event(tu);
397 if (ret)
398 return ret;
399
400unreg:
401 dyn_event_remove(&tu->devent);
402 trace_probe_unlink(&tu->tp);
403 free_trace_uprobe(tu);
404 return 0;
405}
406
407static bool trace_uprobe_has_same_uprobe(struct trace_uprobe *orig,
408 struct trace_uprobe *comp)
409{
410 struct trace_probe_event *tpe = orig->tp.event;
411 struct trace_probe *pos;
412 struct inode *comp_inode = d_real_inode(comp->path.dentry);
413 int i;
414
415 list_for_each_entry(pos, &tpe->probes, list) {
416 orig = container_of(pos, struct trace_uprobe, tp);
417 if (comp_inode != d_real_inode(orig->path.dentry) ||
418 comp->offset != orig->offset)
419 continue;
420
421
422
423
424
425 for (i = 0; i < orig->tp.nr_args; i++) {
426 if (strcmp(orig->tp.args[i].comm,
427 comp->tp.args[i].comm))
428 break;
429 }
430
431 if (i == orig->tp.nr_args)
432 return true;
433 }
434
435 return false;
436}
437
438static int append_trace_uprobe(struct trace_uprobe *tu, struct trace_uprobe *to)
439{
440 int ret;
441
442 ret = trace_probe_compare_arg_type(&tu->tp, &to->tp);
443 if (ret) {
444
445 trace_probe_log_set_index(ret + 1);
446 trace_probe_log_err(0, DIFF_ARG_TYPE);
447 return -EEXIST;
448 }
449 if (trace_uprobe_has_same_uprobe(to, tu)) {
450 trace_probe_log_set_index(0);
451 trace_probe_log_err(0, SAME_PROBE);
452 return -EEXIST;
453 }
454
455
456 ret = trace_probe_append(&tu->tp, &to->tp);
457 if (!ret)
458 dyn_event_add(&tu->devent);
459
460 return ret;
461}
462
463
464
465
466
467
468
469
470
471
472static int validate_ref_ctr_offset(struct trace_uprobe *new)
473{
474 struct dyn_event *pos;
475 struct trace_uprobe *tmp;
476 struct inode *new_inode = d_real_inode(new->path.dentry);
477
478 for_each_trace_uprobe(tmp, pos) {
479 if (new_inode == d_real_inode(tmp->path.dentry) &&
480 new->offset == tmp->offset &&
481 new->ref_ctr_offset != tmp->ref_ctr_offset) {
482 pr_warn("Reference counter offset mismatch.");
483 return -EINVAL;
484 }
485 }
486 return 0;
487}
488
489
490static int register_trace_uprobe(struct trace_uprobe *tu)
491{
492 struct trace_uprobe *old_tu;
493 int ret;
494
495 mutex_lock(&event_mutex);
496
497 ret = validate_ref_ctr_offset(tu);
498 if (ret)
499 goto end;
500
501
502 old_tu = find_probe_event(trace_probe_name(&tu->tp),
503 trace_probe_group_name(&tu->tp));
504 if (old_tu) {
505 if (is_ret_probe(tu) != is_ret_probe(old_tu)) {
506 trace_probe_log_set_index(0);
507 trace_probe_log_err(0, DIFF_PROBE_TYPE);
508 ret = -EEXIST;
509 } else {
510 ret = append_trace_uprobe(tu, old_tu);
511 }
512 goto end;
513 }
514
515 ret = register_uprobe_event(tu);
516 if (ret) {
517 pr_warn("Failed to register probe event(%d)\n", ret);
518 goto end;
519 }
520
521 dyn_event_add(&tu->devent);
522
523end:
524 mutex_unlock(&event_mutex);
525
526 return ret;
527}
528
529
530
531
532
533static int __trace_uprobe_create(int argc, const char **argv)
534{
535 struct trace_uprobe *tu;
536 const char *event = NULL, *group = UPROBE_EVENT_SYSTEM;
537 char *arg, *filename, *rctr, *rctr_end, *tmp;
538 char buf[MAX_EVENT_NAME_LEN];
539 struct path path;
540 unsigned long offset, ref_ctr_offset;
541 bool is_return = false;
542 int i, ret;
543
544 ret = 0;
545 ref_ctr_offset = 0;
546
547 switch (argv[0][0]) {
548 case 'r':
549 is_return = true;
550 break;
551 case 'p':
552 break;
553 default:
554 return -ECANCELED;
555 }
556
557 if (argc < 2)
558 return -ECANCELED;
559
560 if (argv[0][1] == ':')
561 event = &argv[0][2];
562
563 if (!strchr(argv[1], '/'))
564 return -ECANCELED;
565
566 filename = kstrdup(argv[1], GFP_KERNEL);
567 if (!filename)
568 return -ENOMEM;
569
570
571 arg = strrchr(filename, ':');
572 if (!arg || !isdigit(arg[1])) {
573 kfree(filename);
574 return -ECANCELED;
575 }
576
577 trace_probe_log_init("trace_uprobe", argc, argv);
578 trace_probe_log_set_index(1);
579
580 *arg++ = '\0';
581 ret = kern_path(filename, LOOKUP_FOLLOW, &path);
582 if (ret) {
583 trace_probe_log_err(0, FILE_NOT_FOUND);
584 kfree(filename);
585 trace_probe_log_clear();
586 return ret;
587 }
588 if (!d_is_reg(path.dentry)) {
589 trace_probe_log_err(0, NO_REGULAR_FILE);
590 ret = -EINVAL;
591 goto fail_address_parse;
592 }
593
594
595 rctr = strchr(arg, '(');
596 if (rctr) {
597 rctr_end = strchr(rctr, ')');
598 if (!rctr_end) {
599 ret = -EINVAL;
600 rctr_end = rctr + strlen(rctr);
601 trace_probe_log_err(rctr_end - filename,
602 REFCNT_OPEN_BRACE);
603 goto fail_address_parse;
604 } else if (rctr_end[1] != '\0') {
605 ret = -EINVAL;
606 trace_probe_log_err(rctr_end + 1 - filename,
607 BAD_REFCNT_SUFFIX);
608 goto fail_address_parse;
609 }
610
611 *rctr++ = '\0';
612 *rctr_end = '\0';
613 ret = kstrtoul(rctr, 0, &ref_ctr_offset);
614 if (ret) {
615 trace_probe_log_err(rctr - filename, BAD_REFCNT);
616 goto fail_address_parse;
617 }
618 }
619
620
621 tmp = strchr(arg, '%');
622 if (tmp) {
623 if (!strcmp(tmp, "%return")) {
624 *tmp = '\0';
625 is_return = true;
626 } else {
627 trace_probe_log_err(tmp - filename, BAD_ADDR_SUFFIX);
628 ret = -EINVAL;
629 goto fail_address_parse;
630 }
631 }
632
633
634 ret = kstrtoul(arg, 0, &offset);
635 if (ret) {
636 trace_probe_log_err(arg - filename, BAD_UPROBE_OFFS);
637 goto fail_address_parse;
638 }
639
640
641 trace_probe_log_set_index(0);
642 if (event) {
643 ret = traceprobe_parse_event_name(&event, &group, buf,
644 event - argv[0]);
645 if (ret)
646 goto fail_address_parse;
647 } else {
648 char *tail;
649 char *ptr;
650
651 tail = kstrdup(kbasename(filename), GFP_KERNEL);
652 if (!tail) {
653 ret = -ENOMEM;
654 goto fail_address_parse;
655 }
656
657 ptr = strpbrk(tail, ".-_");
658 if (ptr)
659 *ptr = '\0';
660
661 snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_0x%lx", 'p', tail, offset);
662 event = buf;
663 kfree(tail);
664 }
665
666 argc -= 2;
667 argv += 2;
668
669 tu = alloc_trace_uprobe(group, event, argc, is_return);
670 if (IS_ERR(tu)) {
671 ret = PTR_ERR(tu);
672
673 WARN_ON_ONCE(ret != -ENOMEM);
674 goto fail_address_parse;
675 }
676 tu->offset = offset;
677 tu->ref_ctr_offset = ref_ctr_offset;
678 tu->path = path;
679 tu->filename = filename;
680
681
682 for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
683 tmp = kstrdup(argv[i], GFP_KERNEL);
684 if (!tmp) {
685 ret = -ENOMEM;
686 goto error;
687 }
688
689 trace_probe_log_set_index(i + 2);
690 ret = traceprobe_parse_probe_arg(&tu->tp, i, tmp,
691 is_return ? TPARG_FL_RETURN : 0);
692 kfree(tmp);
693 if (ret)
694 goto error;
695 }
696
697 ret = traceprobe_set_print_fmt(&tu->tp, is_ret_probe(tu));
698 if (ret < 0)
699 goto error;
700
701 ret = register_trace_uprobe(tu);
702 if (!ret)
703 goto out;
704
705error:
706 free_trace_uprobe(tu);
707out:
708 trace_probe_log_clear();
709 return ret;
710
711fail_address_parse:
712 trace_probe_log_clear();
713 path_put(&path);
714 kfree(filename);
715
716 return ret;
717}
718
719int trace_uprobe_create(const char *raw_command)
720{
721 return trace_probe_create(raw_command, __trace_uprobe_create);
722}
723
724static int create_or_delete_trace_uprobe(const char *raw_command)
725{
726 int ret;
727
728 if (raw_command[0] == '-')
729 return dyn_event_release(raw_command, &trace_uprobe_ops);
730
731 ret = trace_uprobe_create(raw_command);
732 return ret == -ECANCELED ? -EINVAL : ret;
733}
734
735static int trace_uprobe_release(struct dyn_event *ev)
736{
737 struct trace_uprobe *tu = to_trace_uprobe(ev);
738
739 return unregister_trace_uprobe(tu);
740}
741
742
743static int trace_uprobe_show(struct seq_file *m, struct dyn_event *ev)
744{
745 struct trace_uprobe *tu = to_trace_uprobe(ev);
746 char c = is_ret_probe(tu) ? 'r' : 'p';
747 int i;
748
749 seq_printf(m, "%c:%s/%s %s:0x%0*lx", c, trace_probe_group_name(&tu->tp),
750 trace_probe_name(&tu->tp), tu->filename,
751 (int)(sizeof(void *) * 2), tu->offset);
752
753 if (tu->ref_ctr_offset)
754 seq_printf(m, "(0x%lx)", tu->ref_ctr_offset);
755
756 for (i = 0; i < tu->tp.nr_args; i++)
757 seq_printf(m, " %s=%s", tu->tp.args[i].name, tu->tp.args[i].comm);
758
759 seq_putc(m, '\n');
760 return 0;
761}
762
763static int probes_seq_show(struct seq_file *m, void *v)
764{
765 struct dyn_event *ev = v;
766
767 if (!is_trace_uprobe(ev))
768 return 0;
769
770 return trace_uprobe_show(m, ev);
771}
772
773static const struct seq_operations probes_seq_op = {
774 .start = dyn_event_seq_start,
775 .next = dyn_event_seq_next,
776 .stop = dyn_event_seq_stop,
777 .show = probes_seq_show
778};
779
780static int probes_open(struct inode *inode, struct file *file)
781{
782 int ret;
783
784 ret = security_locked_down(LOCKDOWN_TRACEFS);
785 if (ret)
786 return ret;
787
788 if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
789 ret = dyn_events_release_all(&trace_uprobe_ops);
790 if (ret)
791 return ret;
792 }
793
794 return seq_open(file, &probes_seq_op);
795}
796
797static ssize_t probes_write(struct file *file, const char __user *buffer,
798 size_t count, loff_t *ppos)
799{
800 return trace_parse_run_command(file, buffer, count, ppos,
801 create_or_delete_trace_uprobe);
802}
803
804static const struct file_operations uprobe_events_ops = {
805 .owner = THIS_MODULE,
806 .open = probes_open,
807 .read = seq_read,
808 .llseek = seq_lseek,
809 .release = seq_release,
810 .write = probes_write,
811};
812
813
814static int probes_profile_seq_show(struct seq_file *m, void *v)
815{
816 struct dyn_event *ev = v;
817 struct trace_uprobe *tu;
818
819 if (!is_trace_uprobe(ev))
820 return 0;
821
822 tu = to_trace_uprobe(ev);
823 seq_printf(m, " %s %-44s %15lu\n", tu->filename,
824 trace_probe_name(&tu->tp), tu->nhit);
825 return 0;
826}
827
828static const struct seq_operations profile_seq_op = {
829 .start = dyn_event_seq_start,
830 .next = dyn_event_seq_next,
831 .stop = dyn_event_seq_stop,
832 .show = probes_profile_seq_show
833};
834
835static int profile_open(struct inode *inode, struct file *file)
836{
837 int ret;
838
839 ret = security_locked_down(LOCKDOWN_TRACEFS);
840 if (ret)
841 return ret;
842
843 return seq_open(file, &profile_seq_op);
844}
845
846static const struct file_operations uprobe_profile_ops = {
847 .owner = THIS_MODULE,
848 .open = profile_open,
849 .read = seq_read,
850 .llseek = seq_lseek,
851 .release = seq_release,
852};
853
854struct uprobe_cpu_buffer {
855 struct mutex mutex;
856 void *buf;
857};
858static struct uprobe_cpu_buffer __percpu *uprobe_cpu_buffer;
859static int uprobe_buffer_refcnt;
860
861static int uprobe_buffer_init(void)
862{
863 int cpu, err_cpu;
864
865 uprobe_cpu_buffer = alloc_percpu(struct uprobe_cpu_buffer);
866 if (uprobe_cpu_buffer == NULL)
867 return -ENOMEM;
868
869 for_each_possible_cpu(cpu) {
870 struct page *p = alloc_pages_node(cpu_to_node(cpu),
871 GFP_KERNEL, 0);
872 if (p == NULL) {
873 err_cpu = cpu;
874 goto err;
875 }
876 per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf = page_address(p);
877 mutex_init(&per_cpu_ptr(uprobe_cpu_buffer, cpu)->mutex);
878 }
879
880 return 0;
881
882err:
883 for_each_possible_cpu(cpu) {
884 if (cpu == err_cpu)
885 break;
886 free_page((unsigned long)per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf);
887 }
888
889 free_percpu(uprobe_cpu_buffer);
890 return -ENOMEM;
891}
892
893static int uprobe_buffer_enable(void)
894{
895 int ret = 0;
896
897 BUG_ON(!mutex_is_locked(&event_mutex));
898
899 if (uprobe_buffer_refcnt++ == 0) {
900 ret = uprobe_buffer_init();
901 if (ret < 0)
902 uprobe_buffer_refcnt--;
903 }
904
905 return ret;
906}
907
908static void uprobe_buffer_disable(void)
909{
910 int cpu;
911
912 BUG_ON(!mutex_is_locked(&event_mutex));
913
914 if (--uprobe_buffer_refcnt == 0) {
915 for_each_possible_cpu(cpu)
916 free_page((unsigned long)per_cpu_ptr(uprobe_cpu_buffer,
917 cpu)->buf);
918
919 free_percpu(uprobe_cpu_buffer);
920 uprobe_cpu_buffer = NULL;
921 }
922}
923
924static struct uprobe_cpu_buffer *uprobe_buffer_get(void)
925{
926 struct uprobe_cpu_buffer *ucb;
927 int cpu;
928
929 cpu = raw_smp_processor_id();
930 ucb = per_cpu_ptr(uprobe_cpu_buffer, cpu);
931
932
933
934
935
936 mutex_lock(&ucb->mutex);
937
938 return ucb;
939}
940
941static void uprobe_buffer_put(struct uprobe_cpu_buffer *ucb)
942{
943 mutex_unlock(&ucb->mutex);
944}
945
946static void __uprobe_trace_func(struct trace_uprobe *tu,
947 unsigned long func, struct pt_regs *regs,
948 struct uprobe_cpu_buffer *ucb, int dsize,
949 struct trace_event_file *trace_file)
950{
951 struct uprobe_trace_entry_head *entry;
952 struct trace_buffer *buffer;
953 struct ring_buffer_event *event;
954 void *data;
955 int size, esize;
956 struct trace_event_call *call = trace_probe_event_call(&tu->tp);
957
958 WARN_ON(call != trace_file->event_call);
959
960 if (WARN_ON_ONCE(tu->tp.size + dsize > PAGE_SIZE))
961 return;
962
963 if (trace_trigger_soft_disabled(trace_file))
964 return;
965
966 esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
967 size = esize + tu->tp.size + dsize;
968 event = trace_event_buffer_lock_reserve(&buffer, trace_file,
969 call->event.type, size, 0);
970 if (!event)
971 return;
972
973 entry = ring_buffer_event_data(event);
974 if (is_ret_probe(tu)) {
975 entry->vaddr[0] = func;
976 entry->vaddr[1] = instruction_pointer(regs);
977 data = DATAOF_TRACE_ENTRY(entry, true);
978 } else {
979 entry->vaddr[0] = instruction_pointer(regs);
980 data = DATAOF_TRACE_ENTRY(entry, false);
981 }
982
983 memcpy(data, ucb->buf, tu->tp.size + dsize);
984
985 event_trigger_unlock_commit(trace_file, buffer, event, entry, 0);
986}
987
988
989static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs,
990 struct uprobe_cpu_buffer *ucb, int dsize)
991{
992 struct event_file_link *link;
993
994 if (is_ret_probe(tu))
995 return 0;
996
997 rcu_read_lock();
998 trace_probe_for_each_link_rcu(link, &tu->tp)
999 __uprobe_trace_func(tu, 0, regs, ucb, dsize, link->file);
1000 rcu_read_unlock();
1001
1002 return 0;
1003}
1004
1005static void uretprobe_trace_func(struct trace_uprobe *tu, unsigned long func,
1006 struct pt_regs *regs,
1007 struct uprobe_cpu_buffer *ucb, int dsize)
1008{
1009 struct event_file_link *link;
1010
1011 rcu_read_lock();
1012 trace_probe_for_each_link_rcu(link, &tu->tp)
1013 __uprobe_trace_func(tu, func, regs, ucb, dsize, link->file);
1014 rcu_read_unlock();
1015}
1016
1017
1018static enum print_line_t
1019print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *event)
1020{
1021 struct uprobe_trace_entry_head *entry;
1022 struct trace_seq *s = &iter->seq;
1023 struct trace_uprobe *tu;
1024 u8 *data;
1025
1026 entry = (struct uprobe_trace_entry_head *)iter->ent;
1027 tu = trace_uprobe_primary_from_call(
1028 container_of(event, struct trace_event_call, event));
1029 if (unlikely(!tu))
1030 goto out;
1031
1032 if (is_ret_probe(tu)) {
1033 trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)",
1034 trace_probe_name(&tu->tp),
1035 entry->vaddr[1], entry->vaddr[0]);
1036 data = DATAOF_TRACE_ENTRY(entry, true);
1037 } else {
1038 trace_seq_printf(s, "%s: (0x%lx)",
1039 trace_probe_name(&tu->tp),
1040 entry->vaddr[0]);
1041 data = DATAOF_TRACE_ENTRY(entry, false);
1042 }
1043
1044 if (print_probe_args(s, tu->tp.args, tu->tp.nr_args, data, entry) < 0)
1045 goto out;
1046
1047 trace_seq_putc(s, '\n');
1048
1049 out:
1050 return trace_handle_return(s);
1051}
1052
1053typedef bool (*filter_func_t)(struct uprobe_consumer *self,
1054 enum uprobe_filter_ctx ctx,
1055 struct mm_struct *mm);
1056
1057static int trace_uprobe_enable(struct trace_uprobe *tu, filter_func_t filter)
1058{
1059 int ret;
1060
1061 tu->consumer.filter = filter;
1062 tu->inode = d_real_inode(tu->path.dentry);
1063
1064 if (tu->ref_ctr_offset)
1065 ret = uprobe_register_refctr(tu->inode, tu->offset,
1066 tu->ref_ctr_offset, &tu->consumer);
1067 else
1068 ret = uprobe_register(tu->inode, tu->offset, &tu->consumer);
1069
1070 if (ret)
1071 tu->inode = NULL;
1072
1073 return ret;
1074}
1075
1076static void __probe_event_disable(struct trace_probe *tp)
1077{
1078 struct trace_probe *pos;
1079 struct trace_uprobe *tu;
1080
1081 tu = container_of(tp, struct trace_uprobe, tp);
1082 WARN_ON(!uprobe_filter_is_empty(tu->tp.event->filter));
1083
1084 list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
1085 tu = container_of(pos, struct trace_uprobe, tp);
1086 if (!tu->inode)
1087 continue;
1088
1089 uprobe_unregister(tu->inode, tu->offset, &tu->consumer);
1090 tu->inode = NULL;
1091 }
1092}
1093
1094static int probe_event_enable(struct trace_event_call *call,
1095 struct trace_event_file *file, filter_func_t filter)
1096{
1097 struct trace_probe *pos, *tp;
1098 struct trace_uprobe *tu;
1099 bool enabled;
1100 int ret;
1101
1102 tp = trace_probe_primary_from_call(call);
1103 if (WARN_ON_ONCE(!tp))
1104 return -ENODEV;
1105 enabled = trace_probe_is_enabled(tp);
1106
1107
1108 if (file) {
1109 if (trace_probe_test_flag(tp, TP_FLAG_PROFILE))
1110 return -EINTR;
1111
1112 ret = trace_probe_add_file(tp, file);
1113 if (ret < 0)
1114 return ret;
1115 } else {
1116 if (trace_probe_test_flag(tp, TP_FLAG_TRACE))
1117 return -EINTR;
1118
1119 trace_probe_set_flag(tp, TP_FLAG_PROFILE);
1120 }
1121
1122 tu = container_of(tp, struct trace_uprobe, tp);
1123 WARN_ON(!uprobe_filter_is_empty(tu->tp.event->filter));
1124
1125 if (enabled)
1126 return 0;
1127
1128 ret = uprobe_buffer_enable();
1129 if (ret)
1130 goto err_flags;
1131
1132 list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
1133 tu = container_of(pos, struct trace_uprobe, tp);
1134 ret = trace_uprobe_enable(tu, filter);
1135 if (ret) {
1136 __probe_event_disable(tp);
1137 goto err_buffer;
1138 }
1139 }
1140
1141 return 0;
1142
1143 err_buffer:
1144 uprobe_buffer_disable();
1145
1146 err_flags:
1147 if (file)
1148 trace_probe_remove_file(tp, file);
1149 else
1150 trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
1151
1152 return ret;
1153}
1154
1155static void probe_event_disable(struct trace_event_call *call,
1156 struct trace_event_file *file)
1157{
1158 struct trace_probe *tp;
1159
1160 tp = trace_probe_primary_from_call(call);
1161 if (WARN_ON_ONCE(!tp))
1162 return;
1163
1164 if (!trace_probe_is_enabled(tp))
1165 return;
1166
1167 if (file) {
1168 if (trace_probe_remove_file(tp, file) < 0)
1169 return;
1170
1171 if (trace_probe_is_enabled(tp))
1172 return;
1173 } else
1174 trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
1175
1176 __probe_event_disable(tp);
1177 uprobe_buffer_disable();
1178}
1179
1180static int uprobe_event_define_fields(struct trace_event_call *event_call)
1181{
1182 int ret, size;
1183 struct uprobe_trace_entry_head field;
1184 struct trace_uprobe *tu;
1185
1186 tu = trace_uprobe_primary_from_call(event_call);
1187 if (unlikely(!tu))
1188 return -ENODEV;
1189
1190 if (is_ret_probe(tu)) {
1191 DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_FUNC, 0);
1192 DEFINE_FIELD(unsigned long, vaddr[1], FIELD_STRING_RETIP, 0);
1193 size = SIZEOF_TRACE_ENTRY(true);
1194 } else {
1195 DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_IP, 0);
1196 size = SIZEOF_TRACE_ENTRY(false);
1197 }
1198
1199 return traceprobe_define_arg_fields(event_call, size, &tu->tp);
1200}
1201
1202#ifdef CONFIG_PERF_EVENTS
1203static bool
1204__uprobe_perf_filter(struct trace_uprobe_filter *filter, struct mm_struct *mm)
1205{
1206 struct perf_event *event;
1207
1208 if (filter->nr_systemwide)
1209 return true;
1210
1211 list_for_each_entry(event, &filter->perf_events, hw.tp_list) {
1212 if (event->hw.target->mm == mm)
1213 return true;
1214 }
1215
1216 return false;
1217}
1218
1219static inline bool
1220trace_uprobe_filter_event(struct trace_uprobe_filter *filter,
1221 struct perf_event *event)
1222{
1223 return __uprobe_perf_filter(filter, event->hw.target->mm);
1224}
1225
1226static bool trace_uprobe_filter_remove(struct trace_uprobe_filter *filter,
1227 struct perf_event *event)
1228{
1229 bool done;
1230
1231 write_lock(&filter->rwlock);
1232 if (event->hw.target) {
1233 list_del(&event->hw.tp_list);
1234 done = filter->nr_systemwide ||
1235 (event->hw.target->flags & PF_EXITING) ||
1236 trace_uprobe_filter_event(filter, event);
1237 } else {
1238 filter->nr_systemwide--;
1239 done = filter->nr_systemwide;
1240 }
1241 write_unlock(&filter->rwlock);
1242
1243 return done;
1244}
1245
1246
1247static bool trace_uprobe_filter_add(struct trace_uprobe_filter *filter,
1248 struct perf_event *event)
1249{
1250 bool done;
1251
1252 write_lock(&filter->rwlock);
1253 if (event->hw.target) {
1254
1255
1256
1257
1258
1259
1260
1261
1262 done = filter->nr_systemwide ||
1263 event->parent || event->attr.enable_on_exec ||
1264 trace_uprobe_filter_event(filter, event);
1265 list_add(&event->hw.tp_list, &filter->perf_events);
1266 } else {
1267 done = filter->nr_systemwide;
1268 filter->nr_systemwide++;
1269 }
1270 write_unlock(&filter->rwlock);
1271
1272 return done;
1273}
1274
1275static int uprobe_perf_close(struct trace_event_call *call,
1276 struct perf_event *event)
1277{
1278 struct trace_probe *pos, *tp;
1279 struct trace_uprobe *tu;
1280 int ret = 0;
1281
1282 tp = trace_probe_primary_from_call(call);
1283 if (WARN_ON_ONCE(!tp))
1284 return -ENODEV;
1285
1286 tu = container_of(tp, struct trace_uprobe, tp);
1287 if (trace_uprobe_filter_remove(tu->tp.event->filter, event))
1288 return 0;
1289
1290 list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
1291 tu = container_of(pos, struct trace_uprobe, tp);
1292 ret = uprobe_apply(tu->inode, tu->offset, &tu->consumer, false);
1293 if (ret)
1294 break;
1295 }
1296
1297 return ret;
1298}
1299
1300static int uprobe_perf_open(struct trace_event_call *call,
1301 struct perf_event *event)
1302{
1303 struct trace_probe *pos, *tp;
1304 struct trace_uprobe *tu;
1305 int err = 0;
1306
1307 tp = trace_probe_primary_from_call(call);
1308 if (WARN_ON_ONCE(!tp))
1309 return -ENODEV;
1310
1311 tu = container_of(tp, struct trace_uprobe, tp);
1312 if (trace_uprobe_filter_add(tu->tp.event->filter, event))
1313 return 0;
1314
1315 list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
1316 err = uprobe_apply(tu->inode, tu->offset, &tu->consumer, true);
1317 if (err) {
1318 uprobe_perf_close(call, event);
1319 break;
1320 }
1321 }
1322
1323 return err;
1324}
1325
1326static bool uprobe_perf_filter(struct uprobe_consumer *uc,
1327 enum uprobe_filter_ctx ctx, struct mm_struct *mm)
1328{
1329 struct trace_uprobe_filter *filter;
1330 struct trace_uprobe *tu;
1331 int ret;
1332
1333 tu = container_of(uc, struct trace_uprobe, consumer);
1334 filter = tu->tp.event->filter;
1335
1336 read_lock(&filter->rwlock);
1337 ret = __uprobe_perf_filter(filter, mm);
1338 read_unlock(&filter->rwlock);
1339
1340 return ret;
1341}
1342
1343static void __uprobe_perf_func(struct trace_uprobe *tu,
1344 unsigned long func, struct pt_regs *regs,
1345 struct uprobe_cpu_buffer *ucb, int dsize)
1346{
1347 struct trace_event_call *call = trace_probe_event_call(&tu->tp);
1348 struct uprobe_trace_entry_head *entry;
1349 struct hlist_head *head;
1350 void *data;
1351 int size, esize;
1352 int rctx;
1353
1354 if (bpf_prog_array_valid(call)) {
1355 u32 ret;
1356
1357 preempt_disable();
1358 ret = trace_call_bpf(call, regs);
1359 preempt_enable();
1360 if (!ret)
1361 return;
1362 }
1363
1364 esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
1365
1366 size = esize + tu->tp.size + dsize;
1367 size = ALIGN(size + sizeof(u32), sizeof(u64)) - sizeof(u32);
1368 if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough"))
1369 return;
1370
1371 preempt_disable();
1372 head = this_cpu_ptr(call->perf_events);
1373 if (hlist_empty(head))
1374 goto out;
1375
1376 entry = perf_trace_buf_alloc(size, NULL, &rctx);
1377 if (!entry)
1378 goto out;
1379
1380 if (is_ret_probe(tu)) {
1381 entry->vaddr[0] = func;
1382 entry->vaddr[1] = instruction_pointer(regs);
1383 data = DATAOF_TRACE_ENTRY(entry, true);
1384 } else {
1385 entry->vaddr[0] = instruction_pointer(regs);
1386 data = DATAOF_TRACE_ENTRY(entry, false);
1387 }
1388
1389 memcpy(data, ucb->buf, tu->tp.size + dsize);
1390
1391 if (size - esize > tu->tp.size + dsize) {
1392 int len = tu->tp.size + dsize;
1393
1394 memset(data + len, 0, size - esize - len);
1395 }
1396
1397 perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
1398 head, NULL);
1399 out:
1400 preempt_enable();
1401}
1402
1403
1404static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs,
1405 struct uprobe_cpu_buffer *ucb, int dsize)
1406{
1407 if (!uprobe_perf_filter(&tu->consumer, 0, current->mm))
1408 return UPROBE_HANDLER_REMOVE;
1409
1410 if (!is_ret_probe(tu))
1411 __uprobe_perf_func(tu, 0, regs, ucb, dsize);
1412 return 0;
1413}
1414
1415static void uretprobe_perf_func(struct trace_uprobe *tu, unsigned long func,
1416 struct pt_regs *regs,
1417 struct uprobe_cpu_buffer *ucb, int dsize)
1418{
1419 __uprobe_perf_func(tu, func, regs, ucb, dsize);
1420}
1421
1422int bpf_get_uprobe_info(const struct perf_event *event, u32 *fd_type,
1423 const char **filename, u64 *probe_offset,
1424 bool perf_type_tracepoint)
1425{
1426 const char *pevent = trace_event_name(event->tp_event);
1427 const char *group = event->tp_event->class->system;
1428 struct trace_uprobe *tu;
1429
1430 if (perf_type_tracepoint)
1431 tu = find_probe_event(pevent, group);
1432 else
1433 tu = trace_uprobe_primary_from_call(event->tp_event);
1434 if (!tu)
1435 return -EINVAL;
1436
1437 *fd_type = is_ret_probe(tu) ? BPF_FD_TYPE_URETPROBE
1438 : BPF_FD_TYPE_UPROBE;
1439 *filename = tu->filename;
1440 *probe_offset = tu->offset;
1441 return 0;
1442}
1443#endif
1444
1445static int
1446trace_uprobe_register(struct trace_event_call *event, enum trace_reg type,
1447 void *data)
1448{
1449 struct trace_event_file *file = data;
1450
1451 switch (type) {
1452 case TRACE_REG_REGISTER:
1453 return probe_event_enable(event, file, NULL);
1454
1455 case TRACE_REG_UNREGISTER:
1456 probe_event_disable(event, file);
1457 return 0;
1458
1459#ifdef CONFIG_PERF_EVENTS
1460 case TRACE_REG_PERF_REGISTER:
1461 return probe_event_enable(event, NULL, uprobe_perf_filter);
1462
1463 case TRACE_REG_PERF_UNREGISTER:
1464 probe_event_disable(event, NULL);
1465 return 0;
1466
1467 case TRACE_REG_PERF_OPEN:
1468 return uprobe_perf_open(event, data);
1469
1470 case TRACE_REG_PERF_CLOSE:
1471 return uprobe_perf_close(event, data);
1472
1473#endif
1474 default:
1475 return 0;
1476 }
1477}
1478
1479static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs)
1480{
1481 struct trace_uprobe *tu;
1482 struct uprobe_dispatch_data udd;
1483 struct uprobe_cpu_buffer *ucb;
1484 int dsize, esize;
1485 int ret = 0;
1486
1487
1488 tu = container_of(con, struct trace_uprobe, consumer);
1489 tu->nhit++;
1490
1491 udd.tu = tu;
1492 udd.bp_addr = instruction_pointer(regs);
1493
1494 current->utask->vaddr = (unsigned long) &udd;
1495
1496 if (WARN_ON_ONCE(!uprobe_cpu_buffer))
1497 return 0;
1498
1499 dsize = __get_data_size(&tu->tp, regs);
1500 esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
1501
1502 ucb = uprobe_buffer_get();
1503 store_trace_args(ucb->buf, &tu->tp, regs, esize, dsize);
1504
1505 if (trace_probe_test_flag(&tu->tp, TP_FLAG_TRACE))
1506 ret |= uprobe_trace_func(tu, regs, ucb, dsize);
1507
1508#ifdef CONFIG_PERF_EVENTS
1509 if (trace_probe_test_flag(&tu->tp, TP_FLAG_PROFILE))
1510 ret |= uprobe_perf_func(tu, regs, ucb, dsize);
1511#endif
1512 uprobe_buffer_put(ucb);
1513 return ret;
1514}
1515
1516static int uretprobe_dispatcher(struct uprobe_consumer *con,
1517 unsigned long func, struct pt_regs *regs)
1518{
1519 struct trace_uprobe *tu;
1520 struct uprobe_dispatch_data udd;
1521 struct uprobe_cpu_buffer *ucb;
1522 int dsize, esize;
1523
1524 tu = container_of(con, struct trace_uprobe, consumer);
1525
1526 udd.tu = tu;
1527 udd.bp_addr = func;
1528
1529 current->utask->vaddr = (unsigned long) &udd;
1530
1531 if (WARN_ON_ONCE(!uprobe_cpu_buffer))
1532 return 0;
1533
1534 dsize = __get_data_size(&tu->tp, regs);
1535 esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
1536
1537 ucb = uprobe_buffer_get();
1538 store_trace_args(ucb->buf, &tu->tp, regs, esize, dsize);
1539
1540 if (trace_probe_test_flag(&tu->tp, TP_FLAG_TRACE))
1541 uretprobe_trace_func(tu, func, regs, ucb, dsize);
1542
1543#ifdef CONFIG_PERF_EVENTS
1544 if (trace_probe_test_flag(&tu->tp, TP_FLAG_PROFILE))
1545 uretprobe_perf_func(tu, func, regs, ucb, dsize);
1546#endif
1547 uprobe_buffer_put(ucb);
1548 return 0;
1549}
1550
1551static struct trace_event_functions uprobe_funcs = {
1552 .trace = print_uprobe_event
1553};
1554
1555static struct trace_event_fields uprobe_fields_array[] = {
1556 { .type = TRACE_FUNCTION_TYPE,
1557 .define_fields = uprobe_event_define_fields },
1558 {}
1559};
1560
1561static inline void init_trace_event_call(struct trace_uprobe *tu)
1562{
1563 struct trace_event_call *call = trace_probe_event_call(&tu->tp);
1564 call->event.funcs = &uprobe_funcs;
1565 call->class->fields_array = uprobe_fields_array;
1566
1567 call->flags = TRACE_EVENT_FL_UPROBE | TRACE_EVENT_FL_CAP_ANY;
1568 call->class->reg = trace_uprobe_register;
1569}
1570
1571static int register_uprobe_event(struct trace_uprobe *tu)
1572{
1573 init_trace_event_call(tu);
1574
1575 return trace_probe_register_event_call(&tu->tp);
1576}
1577
1578static int unregister_uprobe_event(struct trace_uprobe *tu)
1579{
1580 return trace_probe_unregister_event_call(&tu->tp);
1581}
1582
1583#ifdef CONFIG_PERF_EVENTS
1584struct trace_event_call *
1585create_local_trace_uprobe(char *name, unsigned long offs,
1586 unsigned long ref_ctr_offset, bool is_return)
1587{
1588 struct trace_uprobe *tu;
1589 struct path path;
1590 int ret;
1591
1592 ret = kern_path(name, LOOKUP_FOLLOW, &path);
1593 if (ret)
1594 return ERR_PTR(ret);
1595
1596 if (!d_is_reg(path.dentry)) {
1597 path_put(&path);
1598 return ERR_PTR(-EINVAL);
1599 }
1600
1601
1602
1603
1604
1605
1606 tu = alloc_trace_uprobe(UPROBE_EVENT_SYSTEM, "DUMMY_EVENT", 0,
1607 is_return);
1608
1609 if (IS_ERR(tu)) {
1610 pr_info("Failed to allocate trace_uprobe.(%d)\n",
1611 (int)PTR_ERR(tu));
1612 path_put(&path);
1613 return ERR_CAST(tu);
1614 }
1615
1616 tu->offset = offs;
1617 tu->path = path;
1618 tu->ref_ctr_offset = ref_ctr_offset;
1619 tu->filename = kstrdup(name, GFP_KERNEL);
1620 init_trace_event_call(tu);
1621
1622 if (traceprobe_set_print_fmt(&tu->tp, is_ret_probe(tu)) < 0) {
1623 ret = -ENOMEM;
1624 goto error;
1625 }
1626
1627 return trace_probe_event_call(&tu->tp);
1628error:
1629 free_trace_uprobe(tu);
1630 return ERR_PTR(ret);
1631}
1632
1633void destroy_local_trace_uprobe(struct trace_event_call *event_call)
1634{
1635 struct trace_uprobe *tu;
1636
1637 tu = trace_uprobe_primary_from_call(event_call);
1638
1639 free_trace_uprobe(tu);
1640}
1641#endif
1642
1643
1644static __init int init_uprobe_trace(void)
1645{
1646 int ret;
1647
1648 ret = dyn_event_register(&trace_uprobe_ops);
1649 if (ret)
1650 return ret;
1651
1652 ret = tracing_init_dentry();
1653 if (ret)
1654 return 0;
1655
1656 trace_create_file("uprobe_events", 0644, NULL,
1657 NULL, &uprobe_events_ops);
1658
1659 trace_create_file("uprobe_profile", 0444, NULL,
1660 NULL, &uprobe_profile_ops);
1661 return 0;
1662}
1663
1664fs_initcall(init_uprobe_trace);
1665