1/*
2 * probe-event.c : perf-probe definition to probe_events format converter
3 *
4 * Written by Masami Hiramatsu <mhiramat@redhat.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 *
20 */
21
22#define _GNU_SOURCE
23#include <sys/utsname.h>
24#include <sys/types.h>
25#include <sys/stat.h>
26#include <fcntl.h>
27#include <errno.h>
28#include <stdio.h>
29#include <unistd.h>
30#include <stdlib.h>
31#include <string.h>
32#include <stdarg.h>
33#include <limits.h>
34#include <elf.h>
35
36#undef _GNU_SOURCE
37#include "util.h"
38#include "event.h"
39#include "string.h"
40#include "strlist.h"
41#include "debug.h"
42#include "cache.h"
43#include "color.h"
44#include "symbol.h"
45#include "thread.h"
46#include "debugfs.h"
47#include "trace-event.h"	/* For __unused */
48#include "probe-event.h"
49#include "probe-finder.h"
50
51#define MAX_CMDLEN 256
52#define MAX_PROBE_ARGS 128
53#define PERFPROBE_GROUP "probe"
54
55bool probe_event_dry_run;	/* Dry run flag */
56
57#define semantic_error(msg ...) pr_err("Semantic error :" msg)
58
59/* If there is no space to write, returns -E2BIG. */
60static int e_snprintf(char *str, size_t size, const char *format, ...)
61	__attribute__((format(printf, 3, 4)));
62
63static int e_snprintf(char *str, size_t size, const char *format, ...)
64{
65	int ret;
66	va_list ap;
67	va_start(ap, format);
68	ret = vsnprintf(str, size, format, ap);
69	va_end(ap);
70	if (ret >= (int)size)
71		ret = -E2BIG;
72	return ret;
73}
74
75static char *synthesize_perf_probe_point(struct perf_probe_point *pp);
76static struct machine machine;
77
78/* Initialize symbol maps and path of vmlinux/modules */
79static int init_vmlinux(void)
80{
81	int ret;
82
83	symbol_conf.sort_by_name = true;
84	if (symbol_conf.vmlinux_name == NULL)
85		symbol_conf.try_vmlinux_path = true;
86	else
87		pr_debug("Use vmlinux: %s\n", symbol_conf.vmlinux_name);
88	ret = symbol__init();
89	if (ret < 0) {
90		pr_debug("Failed to init symbol map.\n");
91		goto out;
92	}
93
94	ret = machine__init(&machine, "", HOST_KERNEL_ID);
95	if (ret < 0)
96		goto out;
97
98	if (machine__create_kernel_maps(&machine) < 0) {
99		pr_debug("machine__create_kernel_maps() failed.\n");
100		goto out;
101	}
102out:
103	if (ret < 0)
104		pr_warning("Failed to init vmlinux path.\n");
105	return ret;
106}
107
108static struct symbol *__find_kernel_function_by_name(const char *name,
109						     struct map **mapp)
110{
111	return machine__find_kernel_function_by_name(&machine, name, mapp,
112						     NULL);
113}
114
115static struct map *kernel_get_module_map(const char *module)
116{
117	struct rb_node *nd;
118	struct map_groups *grp = &machine.kmaps;
119
120	if (!module)
121		module = "kernel";
122
123	for (nd = rb_first(&grp->maps[MAP__FUNCTION]); nd; nd = rb_next(nd)) {
124		struct map *pos = rb_entry(nd, struct map, rb_node);
125		if (strncmp(pos->dso->short_name + 1, module,
126			    pos->dso->short_name_len - 2) == 0) {
127			return pos;
128		}
129	}
130	return NULL;
131}
132
133static struct dso *kernel_get_module_dso(const char *module)
134{
135	struct dso *dso;
136	struct map *map;
137	const char *vmlinux_name;
138
139	if (module) {
140		list_for_each_entry(dso, &machine.kernel_dsos, node) {
141			if (strncmp(dso->short_name + 1, module,
142				    dso->short_name_len - 2) == 0)
143				goto found;
144		}
145		pr_debug("Failed to find module %s.\n", module);
146		return NULL;
147	}
148
149	map = machine.vmlinux_maps[MAP__FUNCTION];
150	dso = map->dso;
151
152	vmlinux_name = symbol_conf.vmlinux_name;
153	if (vmlinux_name) {
154		if (dso__load_vmlinux(dso, map, vmlinux_name, NULL) <= 0)
155			return NULL;
156	} else {
157		if (dso__load_vmlinux_path(dso, map, NULL) <= 0) {
158			pr_debug("Failed to load kernel map.\n");
159			return NULL;
160		}
161	}
162found:
163	return dso;
164}
165
166const char *kernel_get_module_path(const char *module)
167{
168	struct dso *dso = kernel_get_module_dso(module);
169	return (dso) ? dso->long_name : NULL;
170}
171
172#ifdef DWARF_SUPPORT
173static int open_vmlinux(const char *module)
174{
175	const char *path = kernel_get_module_path(module);
176	if (!path) {
177		pr_err("Failed to find path of %s module.\n",
178		       module ?: "kernel");
179		return -ENOENT;
180	}
181	pr_debug("Try to open %s\n", path);
182	return open(path, O_RDONLY);
183}
184
185/*
186 * Convert trace point to probe point with debuginfo
187 * Currently only handles kprobes.
188 */
189static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
190					struct perf_probe_point *pp)
191{
192	struct symbol *sym;
193	struct map *map;
194	u64 addr;
195	int ret = -ENOENT;
196
197	sym = __find_kernel_function_by_name(tp->symbol, &map);
198	if (sym) {
199		addr = map->unmap_ip(map, sym->start + tp->offset);
200		pr_debug("try to find %s+%ld@%" PRIx64 "\n", tp->symbol,
201			 tp->offset, addr);
202		ret = find_perf_probe_point((unsigned long)addr, pp);
203	}
204	if (ret <= 0) {
205		pr_debug("Failed to find corresponding probes from "
206			 "debuginfo. Use kprobe event information.\n");
207		pp->function = strdup(tp->symbol);
208		if (pp->function == NULL)
209			return -ENOMEM;
210		pp->offset = tp->offset;
211	}
212	pp->retprobe = tp->retprobe;
213
214	return 0;
215}
216
217/* Try to find perf_probe_event with debuginfo */
218static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
219					   struct probe_trace_event **tevs,
220					   int max_tevs, const char *module)
221{
222	bool need_dwarf = perf_probe_event_need_dwarf(pev);
223	int fd, ntevs;
224
225	fd = open_vmlinux(module);
226	if (fd < 0) {
227		if (need_dwarf) {
228			pr_warning("Failed to open debuginfo file.\n");
229			return fd;
230		}
231		pr_debug("Could not open vmlinux. Try to use symbols.\n");
232		return 0;
233	}
234
235	/* Searching trace events corresponding to probe event */
236	ntevs = find_probe_trace_events(fd, pev, tevs, max_tevs);
237
238	if (ntevs > 0) {	/* Succeeded to find trace events */
239		pr_debug("find %d probe_trace_events.\n", ntevs);
240		return ntevs;
241	}
242
243	if (ntevs == 0)	{	/* No error but failed to find probe point. */
244		pr_warning("Probe point '%s' not found.\n",
245			   synthesize_perf_probe_point(&pev->point));
246		return -ENOENT;
247	}
248	/* Error path : ntevs < 0 */
249	pr_debug("An error occurred in debuginfo analysis (%d).\n", ntevs);
250	if (ntevs == -EBADF) {
251		pr_warning("Warning: No dwarf info found in the vmlinux - "
252			"please rebuild kernel with CONFIG_DEBUG_INFO=y.\n");
253		if (!need_dwarf) {
254			pr_debug("Trying to use symbols.\n");
255			return 0;
256		}
257	}
258	return ntevs;
259}
260
261/*
262 * Find a src file from a DWARF tag path. Prepend optional source path prefix
263 * and chop off leading directories that do not exist. Result is passed back as
264 * a newly allocated path on success.
265 * Return 0 if file was found and readable, -errno otherwise.
266 */
267static int get_real_path(const char *raw_path, const char *comp_dir,
268			 char **new_path)
269{
270	const char *prefix = symbol_conf.source_prefix;
271
272	if (!prefix) {
273		if (raw_path[0] != '/' && comp_dir)
274			/* If not an absolute path, try to use comp_dir */
275			prefix = comp_dir;
276		else {
277			if (access(raw_path, R_OK) == 0) {
278				*new_path = strdup(raw_path);
279				return 0;
280			} else
281				return -errno;
282		}
283	}
284
285	*new_path = malloc((strlen(prefix) + strlen(raw_path) + 2));
286	if (!*new_path)
287		return -ENOMEM;
288
289	for (;;) {
290		sprintf(*new_path, "%s/%s", prefix, raw_path);
291
292		if (access(*new_path, R_OK) == 0)
293			return 0;
294
295		if (!symbol_conf.source_prefix)
296			/* In case of searching comp_dir, don't retry */
297			return -errno;
298
299		switch (errno) {
300		case ENAMETOOLONG:
301		case ENOENT:
302		case EROFS:
303		case EFAULT:
304			raw_path = strchr(++raw_path, '/');
305			if (!raw_path) {
306				free(*new_path);
307				*new_path = NULL;
308				return -ENOENT;
309			}
310			continue;
311
312		default:
313			free(*new_path);
314			*new_path = NULL;
315			return -errno;
316		}
317	}
318}
319
320#define LINEBUF_SIZE 256
321#define NR_ADDITIONAL_LINES 2
322
323static int __show_one_line(FILE *fp, int l, bool skip, bool show_num)
324{
325	char buf[LINEBUF_SIZE];
326	const char *color = show_num ? "" : PERF_COLOR_BLUE;
327	const char *prefix = NULL;
328
329	do {
330		if (fgets(buf, LINEBUF_SIZE, fp) == NULL)
331			goto error;
332		if (skip)
333			continue;
334		if (!prefix) {
335			prefix = show_num ? "%7d  " : "         ";
336			color_fprintf(stdout, color, prefix, l);
337		}
338		color_fprintf(stdout, color, "%s", buf);
339
340	} while (strchr(buf, '\n') == NULL);
341
342	return 1;
343error:
344	if (ferror(fp)) {
345		pr_warning("File read error: %s\n", strerror(errno));
346		return -1;
347	}
348	return 0;
349}
350
351static int _show_one_line(FILE *fp, int l, bool skip, bool show_num)
352{
353	int rv = __show_one_line(fp, l, skip, show_num);
354	if (rv == 0) {
355		pr_warning("Source file is shorter than expected.\n");
356		rv = -1;
357	}
358	return rv;
359}
360
361#define show_one_line_with_num(f,l)	_show_one_line(f,l,false,true)
362#define show_one_line(f,l)		_show_one_line(f,l,false,false)
363#define skip_one_line(f,l)		_show_one_line(f,l,true,false)
364#define show_one_line_or_eof(f,l)	__show_one_line(f,l,false,false)
365
366/*
367 * Show line-range always requires debuginfo to find source file and
368 * line number.
369 */
370int show_line_range(struct line_range *lr, const char *module)
371{
372	int l = 1;
373	struct line_node *ln;
374	FILE *fp;
375	int fd, ret;
376	char *tmp;
377
378	/* Search a line range */
379	ret = init_vmlinux();
380	if (ret < 0)
381		return ret;
382
383	fd = open_vmlinux(module);
384	if (fd < 0) {
385		pr_warning("Failed to open debuginfo file.\n");
386		return fd;
387	}
388
389	ret = find_line_range(fd, lr);
390	if (ret == 0) {
391		pr_warning("Specified source line is not found.\n");
392		return -ENOENT;
393	} else if (ret < 0) {
394		pr_warning("Debuginfo analysis failed. (%d)\n", ret);
395		return ret;
396	}
397
398	/* Convert source file path */
399	tmp = lr->path;
400	ret = get_real_path(tmp, lr->comp_dir, &lr->path);
401	free(tmp);	/* Free old path */
402	if (ret < 0) {
403		pr_warning("Failed to find source file. (%d)\n", ret);
404		return ret;
405	}
406
407	setup_pager();
408
409	if (lr->function)
410		fprintf(stdout, "<%s@%s:%d>\n", lr->function, lr->path,
411			lr->start - lr->offset);
412	else
413		fprintf(stdout, "<%s:%d>\n", lr->path, lr->start);
414
415	fp = fopen(lr->path, "r");
416	if (fp == NULL) {
417		pr_warning("Failed to open %s: %s\n", lr->path,
418			   strerror(errno));
419		return -errno;
420	}
421	/* Skip to starting line number */
422	while (l < lr->start) {
423		ret = skip_one_line(fp, l++);
424		if (ret < 0)
425			goto end;
426	}
427
428	list_for_each_entry(ln, &lr->line_list, list) {
429		for (; ln->line > l; l++) {
430			ret = show_one_line(fp, l - lr->offset);
431			if (ret < 0)
432				goto end;
433		}
434		ret = show_one_line_with_num(fp, l++ - lr->offset);
435		if (ret < 0)
436			goto end;
437	}
438
439	if (lr->end == INT_MAX)
440		lr->end = l + NR_ADDITIONAL_LINES;
441	while (l <= lr->end) {
442		ret = show_one_line_or_eof(fp, l++ - lr->offset);
443		if (ret <= 0)
444			break;
445	}
446end:
447	fclose(fp);
448	return ret;
449}
450
451static int show_available_vars_at(int fd, struct perf_probe_event *pev,
452				  int max_vls, struct strfilter *_filter,
453				  bool externs)
454{
455	char *buf;
456	int ret, i, nvars;
457	struct str_node *node;
458	struct variable_list *vls = NULL, *vl;
459	const char *var;
460
461	buf = synthesize_perf_probe_point(&pev->point);
462	if (!buf)
463		return -EINVAL;
464	pr_debug("Searching variables at %s\n", buf);
465
466	ret = find_available_vars_at(fd, pev, &vls, max_vls, externs);
467	if (ret <= 0) {
468		pr_err("Failed to find variables at %s (%d)\n", buf, ret);
469		goto end;
470	}
471	/* Some variables are found */
472	fprintf(stdout, "Available variables at %s\n", buf);
473	for (i = 0; i < ret; i++) {
474		vl = &vls[i];
475		/*
476		 * A probe point might be converted to
477		 * several trace points.
478		 */
479		fprintf(stdout, "\t@<%s+%lu>\n", vl->point.symbol,
480			vl->point.offset);
481		free(vl->point.symbol);
482		nvars = 0;
483		if (vl->vars) {
484			strlist__for_each(node, vl->vars) {
485				var = strchr(node->s, '\t') + 1;
486				if (strfilter__compare(_filter, var)) {
487					fprintf(stdout, "\t\t%s\n", node->s);
488					nvars++;
489				}
490			}
491			strlist__delete(vl->vars);
492		}
493		if (nvars == 0)
494			fprintf(stdout, "\t\t(No matched variables)\n");
495	}
496	free(vls);
497end:
498	free(buf);
499	return ret;
500}
501
502/* Show available variables on given probe point */
503int show_available_vars(struct perf_probe_event *pevs, int npevs,
504			int max_vls, const char *module,
505			struct strfilter *_filter, bool externs)
506{
507	int i, fd, ret = 0;
508
509	ret = init_vmlinux();
510	if (ret < 0)
511		return ret;
512
513	setup_pager();
514
515	for (i = 0; i < npevs && ret >= 0; i++) {
516		fd = open_vmlinux(module);
517		if (fd < 0) {
518			pr_warning("Failed to open debug information file.\n");
519			ret = fd;
520			break;
521		}
522		ret = show_available_vars_at(fd, &pevs[i], max_vls, _filter,
523					     externs);
524	}
525	return ret;
526}
527
528#else	/* !DWARF_SUPPORT */
529
530static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
531					struct perf_probe_point *pp)
532{
533	struct symbol *sym;
534
535	sym = __find_kernel_function_by_name(tp->symbol, NULL);
536	if (!sym) {
537		pr_err("Failed to find symbol %s in kernel.\n", tp->symbol);
538		return -ENOENT;
539	}
540	pp->function = strdup(tp->symbol);
541	if (pp->function == NULL)
542		return -ENOMEM;
543	pp->offset = tp->offset;
544	pp->retprobe = tp->retprobe;
545
546	return 0;
547}
548
549static int try_to_find_probe_trace_events(struct perf_probe_event *pev,
550				struct probe_trace_event **tevs __unused,
551				int max_tevs __unused, const char *mod __unused)
552{
553	if (perf_probe_event_need_dwarf(pev)) {
554		pr_warning("Debuginfo-analysis is not supported.\n");
555		return -ENOSYS;
556	}
557	return 0;
558}
559
560int show_line_range(struct line_range *lr __unused, const char *module __unused)
561{
562	pr_warning("Debuginfo-analysis is not supported.\n");
563	return -ENOSYS;
564}
565
566int show_available_vars(struct perf_probe_event *pevs __unused,
567			int npevs __unused, int max_vls __unused,
568			const char *module __unused,
569			struct strfilter *filter __unused,
570			bool externs __unused)
571{
572	pr_warning("Debuginfo-analysis is not supported.\n");
573	return -ENOSYS;
574}
575#endif
576
577static int parse_line_num(char **ptr, int *val, const char *what)
578{
579	const char *start = *ptr;
580
581	errno = 0;
582	*val = strtol(*ptr, ptr, 0);
583	if (errno || *ptr == start) {
584		semantic_error("'%s' is not a valid number.\n", what);
585		return -EINVAL;
586	}
587	return 0;
588}
589
590/*
591 * Stuff 'lr' according to the line range described by 'arg'.
592 * The line range syntax is described by:
593 *
594 *         SRC[:SLN[+NUM|-ELN]]
595 *         FNC[@SRC][:SLN[+NUM|-ELN]]
596 */
597int parse_line_range_desc(const char *arg, struct line_range *lr)
598{
599	char *range, *file, *name = strdup(arg);
600	int err;
601
602	if (!name)
603		return -ENOMEM;
604
605	lr->start = 0;
606	lr->end = INT_MAX;
607
608	range = strchr(name, ':');
609	if (range) {
610		*range++ = '\0';
611
612		err = parse_line_num(&range, &lr->start, "start line");
613		if (err)
614			goto err;
615
616		if (*range == '+' || *range == '-') {
617			const char c = *range++;
618
619			err = parse_line_num(&range, &lr->end, "end line");
620			if (err)
621				goto err;
622
623			if (c == '+') {
624				lr->end += lr->start;
625				/*
626				 * Adjust the number of lines here.
627				 * If the number of lines == 1, the
628				 * the end of line should be equal to
629				 * the start of line.
630				 */
631				lr->end--;
632			}
633		}
634
635		pr_debug("Line range is %d to %d\n", lr->start, lr->end);
636
637		err = -EINVAL;
638		if (lr->start > lr->end) {
639			semantic_error("Start line must be smaller"
640				       " than end line.\n");
641			goto err;
642		}
643		if (*range != '\0') {
644			semantic_error("Tailing with invalid str '%s'.\n", range);
645			goto err;
646		}
647	}
648
649	file = strchr(name, '@');
650	if (file) {
651		*file = '\0';
652		lr->file = strdup(++file);
653		if (lr->file == NULL) {
654			err = -ENOMEM;
655			goto err;
656		}
657		lr->function = name;
658	} else if (strchr(name, '.'))
659		lr->file = name;
660	else
661		lr->function = name;
662
663	return 0;
664err:
665	free(name);
666	return err;
667}
668
669/* Check the name is good for event/group */
670static bool check_event_name(const char *name)
671{
672	if (!isalpha(*name) && *name != '_')
673		return false;
674	while (*++name != '\0') {
675		if (!isalpha(*name) && !isdigit(*name) && *name != '_')
676			return false;
677	}
678	return true;
679}
680
681/* Parse probepoint definition. */
682static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev)
683{
684	struct perf_probe_point *pp = &pev->point;
685	char *ptr, *tmp;
686	char c, nc = 0;
687	/*
688	 * <Syntax>
689	 * perf probe [EVENT=]SRC[:LN|;PTN]
690	 * perf probe [EVENT=]FUNC[@SRC][+OFFS|%return|:LN|;PAT]
691	 *
692	 * TODO:Group name support
693	 */
694
695	ptr = strpbrk(arg, ";=@+%");
696	if (ptr && *ptr == '=') {	/* Event name */
697		*ptr = '\0';
698		tmp = ptr + 1;
699		if (strchr(arg, ':')) {
700			semantic_error("Group name is not supported yet.\n");
701			return -ENOTSUP;
702		}
703		if (!check_event_name(arg)) {
704			semantic_error("%s is bad for event name -it must "
705				       "follow C symbol-naming rule.\n", arg);
706			return -EINVAL;
707		}
708		pev->event = strdup(arg);
709		if (pev->event == NULL)
710			return -ENOMEM;
711		pev->group = NULL;
712		arg = tmp;
713	}
714
715	ptr = strpbrk(arg, ";:+@%");
716	if (ptr) {
717		nc = *ptr;
718		*ptr++ = '\0';
719	}
720
721	tmp = strdup(arg);
722	if (tmp == NULL)
723		return -ENOMEM;
724
725	/* Check arg is function or file and copy it */
726	if (strchr(tmp, '.'))	/* File */
727		pp->file = tmp;
728	else			/* Function */
729		pp->function = tmp;
730
731	/* Parse other options */
732	while (ptr) {
733		arg = ptr;
734		c = nc;
735		if (c == ';') {	/* Lazy pattern must be the last part */
736			pp->lazy_line = strdup(arg);
737			if (pp->lazy_line == NULL)
738				return -ENOMEM;
739			break;
740		}
741		ptr = strpbrk(arg, ";:+@%");
742		if (ptr) {
743			nc = *ptr;
744			*ptr++ = '\0';
745		}
746		switch (c) {
747		case ':':	/* Line number */
748			pp->line = strtoul(arg, &tmp, 0);
749			if (*tmp != '\0') {
750				semantic_error("There is non-digit char"
751					       " in line number.\n");
752				return -EINVAL;
753			}
754			break;
755		case '+':	/* Byte offset from a symbol */
756			pp->offset = strtoul(arg, &tmp, 0);
757			if (*tmp != '\0') {
758				semantic_error("There is non-digit character"
759						" in offset.\n");
760				return -EINVAL;
761			}
762			break;
763		case '@':	/* File name */
764			if (pp->file) {
765				semantic_error("SRC@SRC is not allowed.\n");
766				return -EINVAL;
767			}
768			pp->file = strdup(arg);
769			if (pp->file == NULL)
770				return -ENOMEM;
771			break;
772		case '%':	/* Probe places */
773			if (strcmp(arg, "return") == 0) {
774				pp->retprobe = 1;
775			} else {	/* Others not supported yet */
776				semantic_error("%%%s is not supported.\n", arg);
777				return -ENOTSUP;
778			}
779			break;
780		default:	/* Buggy case */
781			pr_err("This program has a bug at %s:%d.\n",
782				__FILE__, __LINE__);
783			return -ENOTSUP;
784			break;
785		}
786	}
787
788	/* Exclusion check */
789	if (pp->lazy_line && pp->line) {
790		semantic_error("Lazy pattern can't be used with"
791			       " line number.\n");
792		return -EINVAL;
793	}
794
795	if (pp->lazy_line && pp->offset) {
796		semantic_error("Lazy pattern can't be used with offset.\n");
797		return -EINVAL;
798	}
799
800	if (pp->line && pp->offset) {
801		semantic_error("Offset can't be used with line number.\n");
802		return -EINVAL;
803	}
804
805	if (!pp->line && !pp->lazy_line && pp->file && !pp->function) {
806		semantic_error("File always requires line number or "
807			       "lazy pattern.\n");
808		return -EINVAL;
809	}
810
811	if (pp->offset && !pp->function) {
812		semantic_error("Offset requires an entry function.\n");
813		return -EINVAL;
814	}
815
816	if (pp->retprobe && !pp->function) {
817		semantic_error("Return probe requires an entry function.\n");
818		return -EINVAL;
819	}
820
821	if ((pp->offset || pp->line || pp->lazy_line) && pp->retprobe) {
822		semantic_error("Offset/Line/Lazy pattern can't be used with "
823			       "return probe.\n");
824		return -EINVAL;
825	}
826
827	pr_debug("symbol:%s file:%s line:%d offset:%lu return:%d lazy:%s\n",
828		 pp->function, pp->file, pp->line, pp->offset, pp->retprobe,
829		 pp->lazy_line);
830	return 0;
831}
832
833/* Parse perf-probe event argument */
834static int parse_perf_probe_arg(char *str, struct perf_probe_arg *arg)
835{
836	char *tmp, *goodname;
837	struct perf_probe_arg_field **fieldp;
838
839	pr_debug("parsing arg: %s into ", str);
840
841	tmp = strchr(str, '=');
842	if (tmp) {
843		arg->name = strndup(str, tmp - str);
844		if (arg->name == NULL)
845			return -ENOMEM;
846		pr_debug("name:%s ", arg->name);
847		str = tmp + 1;
848	}
849
850	tmp = strchr(str, ':');
851	if (tmp) {	/* Type setting */
852		*tmp = '\0';
853		arg->type = strdup(tmp + 1);
854		if (arg->type == NULL)
855			return -ENOMEM;
856		pr_debug("type:%s ", arg->type);
857	}
858
859	tmp = strpbrk(str, "-.[");
860	if (!is_c_varname(str) || !tmp) {
861		/* A variable, register, symbol or special value */
862		arg->var = strdup(str);
863		if (arg->var == NULL)
864			return -ENOMEM;
865		pr_debug("%s\n", arg->var);
866		return 0;
867	}
868
869	/* Structure fields or array element */
870	arg->var = strndup(str, tmp - str);
871	if (arg->var == NULL)
872		return -ENOMEM;
873	goodname = arg->var;
874	pr_debug("%s, ", arg->var);
875	fieldp = &arg->field;
876
877	do {
878		*fieldp = zalloc(sizeof(struct perf_probe_arg_field));
879		if (*fieldp == NULL)
880			return -ENOMEM;
881		if (*tmp == '[') {	/* Array */
882			str = tmp;
883			(*fieldp)->index = strtol(str + 1, &tmp, 0);
884			(*fieldp)->ref = true;
885			if (*tmp != ']' || tmp == str + 1) {
886				semantic_error("Array index must be a"
887						" number.\n");
888				return -EINVAL;
889			}
890			tmp++;
891			if (*tmp == '\0')
892				tmp = NULL;
893		} else {		/* Structure */
894			if (*tmp == '.') {
895				str = tmp + 1;
896				(*fieldp)->ref = false;
897			} else if (tmp[1] == '>') {
898				str = tmp + 2;
899				(*fieldp)->ref = true;
900			} else {
901				semantic_error("Argument parse error: %s\n",
902					       str);
903				return -EINVAL;
904			}
905			tmp = strpbrk(str, "-.[");
906		}
907		if (tmp) {
908			(*fieldp)->name = strndup(str, tmp - str);
909			if ((*fieldp)->name == NULL)
910				return -ENOMEM;
911			if (*str != '[')
912				goodname = (*fieldp)->name;
913			pr_debug("%s(%d), ", (*fieldp)->name, (*fieldp)->ref);
914			fieldp = &(*fieldp)->next;
915		}
916	} while (tmp);
917	(*fieldp)->name = strdup(str);
918	if ((*fieldp)->name == NULL)
919		return -ENOMEM;
920	if (*str != '[')
921		goodname = (*fieldp)->name;
922	pr_debug("%s(%d)\n", (*fieldp)->name, (*fieldp)->ref);
923
924	/* If no name is specified, set the last field name (not array index)*/
925	if (!arg->name) {
926		arg->name = strdup(goodname);
927		if (arg->name == NULL)
928			return -ENOMEM;
929	}
930	return 0;
931}
932
933/* Parse perf-probe event command */
934int parse_perf_probe_command(const char *cmd, struct perf_probe_event *pev)
935{
936	char **argv;
937	int argc, i, ret = 0;
938
939	argv = argv_split(cmd, &argc);
940	if (!argv) {
941		pr_debug("Failed to split arguments.\n");
942		return -ENOMEM;
943	}
944	if (argc - 1 > MAX_PROBE_ARGS) {
945		semantic_error("Too many probe arguments (%d).\n", argc - 1);
946		ret = -ERANGE;
947		goto out;
948	}
949	/* Parse probe point */
950	ret = parse_perf_probe_point(argv[0], pev);
951	if (ret < 0)
952		goto out;
953
954	/* Copy arguments and ensure return probe has no C argument */
955	pev->nargs = argc - 1;
956	pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
957	if (pev->args == NULL) {
958		ret = -ENOMEM;
959		goto out;
960	}
961	for (i = 0; i < pev->nargs && ret >= 0; i++) {
962		ret = parse_perf_probe_arg(argv[i + 1], &pev->args[i]);
963		if (ret >= 0 &&
964		    is_c_varname(pev->args[i].var) && pev->point.retprobe) {
965			semantic_error("You can't specify local variable for"
966				       " kretprobe.\n");
967			ret = -EINVAL;
968		}
969	}
970out:
971	argv_free(argv);
972
973	return ret;
974}
975
976/* Return true if this perf_probe_event requires debuginfo */
977bool perf_probe_event_need_dwarf(struct perf_probe_event *pev)
978{
979	int i;
980
981	if (pev->point.file || pev->point.line || pev->point.lazy_line)
982		return true;
983
984	for (i = 0; i < pev->nargs; i++)
985		if (is_c_varname(pev->args[i].var))
986			return true;
987
988	return false;
989}
990
991/* Parse probe_events event into struct probe_point */
992static int parse_probe_trace_command(const char *cmd,
993					struct probe_trace_event *tev)
994{
995	struct probe_trace_point *tp = &tev->point;
996	char pr;
997	char *p;
998	int ret, i, argc;
999	char **argv;
1000
1001	pr_debug("Parsing probe_events: %s\n", cmd);
1002	argv = argv_split(cmd, &argc);
1003	if (!argv) {
1004		pr_debug("Failed to split arguments.\n");
1005		return -ENOMEM;
1006	}
1007	if (argc < 2) {
1008		semantic_error("Too few probe arguments.\n");
1009		ret = -ERANGE;
1010		goto out;
1011	}
1012
1013	/* Scan event and group name. */
1014	ret = sscanf(argv[0], "%c:%a[^/ \t]/%a[^ \t]",
1015		     &pr, (float *)(void *)&tev->group,
1016		     (float *)(void *)&tev->event);
1017	if (ret != 3) {
1018		semantic_error("Failed to parse event name: %s\n", argv[0]);
1019		ret = -EINVAL;
1020		goto out;
1021	}
1022	pr_debug("Group:%s Event:%s probe:%c\n", tev->group, tev->event, pr);
1023
1024	tp->retprobe = (pr == 'r');
1025
1026	/* Scan function name and offset */
1027	ret = sscanf(argv[1], "%a[^+]+%lu", (float *)(void *)&tp->symbol,
1028		     &tp->offset);
1029	if (ret == 1)
1030		tp->offset = 0;
1031
1032	tev->nargs = argc - 2;
1033	tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
1034	if (tev->args == NULL) {
1035		ret = -ENOMEM;
1036		goto out;
1037	}
1038	for (i = 0; i < tev->nargs; i++) {
1039		p = strchr(argv[i + 2], '=');
1040		if (p)	/* We don't need which register is assigned. */
1041			*p++ = '\0';
1042		else
1043			p = argv[i + 2];
1044		tev->args[i].name = strdup(argv[i + 2]);
1045		/* TODO: parse regs and offset */
1046		tev->args[i].value = strdup(p);
1047		if (tev->args[i].name == NULL || tev->args[i].value == NULL) {
1048			ret = -ENOMEM;
1049			goto out;
1050		}
1051	}
1052	ret = 0;
1053out:
1054	argv_free(argv);
1055	return ret;
1056}
1057
1058/* Compose only probe arg */
1059int synthesize_perf_probe_arg(struct perf_probe_arg *pa, char *buf, size_t len)
1060{
1061	struct perf_probe_arg_field *field = pa->field;
1062	int ret;
1063	char *tmp = buf;
1064
1065	if (pa->name && pa->var)
1066		ret = e_snprintf(tmp, len, "%s=%s", pa->name, pa->var);
1067	else
1068		ret = e_snprintf(tmp, len, "%s", pa->name ? pa->name : pa->var);
1069	if (ret <= 0)
1070		goto error;
1071	tmp += ret;
1072	len -= ret;
1073
1074	while (field) {
1075		if (field->name[0] == '[')
1076			ret = e_snprintf(tmp, len, "%s", field->name);
1077		else
1078			ret = e_snprintf(tmp, len, "%s%s",
1079					 field->ref ? "->" : ".", field->name);
1080		if (ret <= 0)
1081			goto error;
1082		tmp += ret;
1083		len -= ret;
1084		field = field->next;
1085	}
1086
1087	if (pa->type) {
1088		ret = e_snprintf(tmp, len, ":%s", pa->type);
1089		if (ret <= 0)
1090			goto error;
1091		tmp += ret;
1092		len -= ret;
1093	}
1094
1095	return tmp - buf;
1096error:
1097	pr_debug("Failed to synthesize perf probe argument: %s\n",
1098		 strerror(-ret));
1099	return ret;
1100}
1101
1102/* Compose only probe point (not argument) */
1103static char *synthesize_perf_probe_point(struct perf_probe_point *pp)
1104{
1105	char *buf, *tmp;
1106	char offs[32] = "", line[32] = "", file[32] = "";
1107	int ret, len;
1108
1109	buf = zalloc(MAX_CMDLEN);
1110	if (buf == NULL) {
1111		ret = -ENOMEM;
1112		goto error;
1113	}
1114	if (pp->offset) {
1115		ret = e_snprintf(offs, 32, "+%lu", pp->offset);
1116		if (ret <= 0)
1117			goto error;
1118	}
1119	if (pp->line) {
1120		ret = e_snprintf(line, 32, ":%d", pp->line);
1121		if (ret <= 0)
1122			goto error;
1123	}
1124	if (pp->file) {
1125		tmp = pp->file;
1126		len = strlen(tmp);
1127		if (len > 30) {
1128			tmp = strchr(pp->file + len - 30, '/');
1129			tmp = tmp ? tmp + 1 : pp->file + len - 30;
1130		}
1131		ret = e_snprintf(file, 32, "@%s", tmp);
1132		if (ret <= 0)
1133			goto error;
1134	}
1135
1136	if (pp->function)
1137		ret = e_snprintf(buf, MAX_CMDLEN, "%s%s%s%s%s", pp->function,
1138				 offs, pp->retprobe ? "%return" : "", line,
1139				 file);
1140	else
1141		ret = e_snprintf(buf, MAX_CMDLEN, "%s%s", file, line);
1142	if (ret <= 0)
1143		goto error;
1144
1145	return buf;
1146error:
1147	pr_debug("Failed to synthesize perf probe point: %s\n",
1148		 strerror(-ret));
1149	if (buf)
1150		free(buf);
1151	return NULL;
1152}
1153
1154#if 0
1155char *synthesize_perf_probe_command(struct perf_probe_event *pev)
1156{
1157	char *buf;
1158	int i, len, ret;
1159
1160	buf = synthesize_perf_probe_point(&pev->point);
1161	if (!buf)
1162		return NULL;
1163
1164	len = strlen(buf);
1165	for (i = 0; i < pev->nargs; i++) {
1166		ret = e_snprintf(&buf[len], MAX_CMDLEN - len, " %s",
1167				 pev->args[i].name);
1168		if (ret <= 0) {
1169			free(buf);
1170			return NULL;
1171		}
1172		len += ret;
1173	}
1174
1175	return buf;
1176}
1177#endif
1178
1179static int __synthesize_probe_trace_arg_ref(struct probe_trace_arg_ref *ref,
1180					     char **buf, size_t *buflen,
1181					     int depth)
1182{
1183	int ret;
1184	if (ref->next) {
1185		depth = __synthesize_probe_trace_arg_ref(ref->next, buf,
1186							 buflen, depth + 1);
1187		if (depth < 0)
1188			goto out;
1189	}
1190
1191	ret = e_snprintf(*buf, *buflen, "%+ld(", ref->offset);
1192	if (ret < 0)
1193		depth = ret;
1194	else {
1195		*buf += ret;
1196		*buflen -= ret;
1197	}
1198out:
1199	return depth;
1200
1201}
1202
1203static int synthesize_probe_trace_arg(struct probe_trace_arg *arg,
1204				       char *buf, size_t buflen)
1205{
1206	struct probe_trace_arg_ref *ref = arg->ref;
1207	int ret, depth = 0;
1208	char *tmp = buf;
1209
1210	/* Argument name or separator */
1211	if (arg->name)
1212		ret = e_snprintf(buf, buflen, " %s=", arg->name);
1213	else
1214		ret = e_snprintf(buf, buflen, " ");
1215	if (ret < 0)
1216		return ret;
1217	buf += ret;
1218	buflen -= ret;
1219
1220	/* Special case: @XXX */
1221	if (arg->value[0] == '@' && arg->ref)
1222			ref = ref->next;
1223
1224	/* Dereferencing arguments */
1225	if (ref) {
1226		depth = __synthesize_probe_trace_arg_ref(ref, &buf,
1227							  &buflen, 1);
1228		if (depth < 0)
1229			return depth;
1230	}
1231
1232	/* Print argument value */
1233	if (arg->value[0] == '@' && arg->ref)
1234		ret = e_snprintf(buf, buflen, "%s%+ld", arg->value,
1235				 arg->ref->offset);
1236	else
1237		ret = e_snprintf(buf, buflen, "%s", arg->value);
1238	if (ret < 0)
1239		return ret;
1240	buf += ret;
1241	buflen -= ret;
1242
1243	/* Closing */
1244	while (depth--) {
1245		ret = e_snprintf(buf, buflen, ")");
1246		if (ret < 0)
1247			return ret;
1248		buf += ret;
1249		buflen -= ret;
1250	}
1251	/* Print argument type */
1252	if (arg->type) {
1253		ret = e_snprintf(buf, buflen, ":%s", arg->type);
1254		if (ret <= 0)
1255			return ret;
1256		buf += ret;
1257	}
1258
1259	return buf - tmp;
1260}
1261
1262char *synthesize_probe_trace_command(struct probe_trace_event *tev)
1263{
1264	struct probe_trace_point *tp = &tev->point;
1265	char *buf;
1266	int i, len, ret;
1267
1268	buf = zalloc(MAX_CMDLEN);
1269	if (buf == NULL)
1270		return NULL;
1271
1272	len = e_snprintf(buf, MAX_CMDLEN, "%c:%s/%s %s+%lu",
1273			 tp->retprobe ? 'r' : 'p',
1274			 tev->group, tev->event,
1275			 tp->symbol, tp->offset);
1276	if (len <= 0)
1277		goto error;
1278
1279	for (i = 0; i < tev->nargs; i++) {
1280		ret = synthesize_probe_trace_arg(&tev->args[i], buf + len,
1281						  MAX_CMDLEN - len);
1282		if (ret <= 0)
1283			goto error;
1284		len += ret;
1285	}
1286
1287	return buf;
1288error:
1289	free(buf);
1290	return NULL;
1291}
1292
1293static int convert_to_perf_probe_event(struct probe_trace_event *tev,
1294				       struct perf_probe_event *pev)
1295{
1296	char buf[64] = "";
1297	int i, ret;
1298
1299	/* Convert event/group name */
1300	pev->event = strdup(tev->event);
1301	pev->group = strdup(tev->group);
1302	if (pev->event == NULL || pev->group == NULL)
1303		return -ENOMEM;
1304
1305	/* Convert trace_point to probe_point */
1306	ret = kprobe_convert_to_perf_probe(&tev->point, &pev->point);
1307	if (ret < 0)
1308		return ret;
1309
1310	/* Convert trace_arg to probe_arg */
1311	pev->nargs = tev->nargs;
1312	pev->args = zalloc(sizeof(struct perf_probe_arg) * pev->nargs);
1313	if (pev->args == NULL)
1314		return -ENOMEM;
1315	for (i = 0; i < tev->nargs && ret >= 0; i++) {
1316		if (tev->args[i].name)
1317			pev->args[i].name = strdup(tev->args[i].name);
1318		else {
1319			ret = synthesize_probe_trace_arg(&tev->args[i],
1320							  buf, 64);
1321			pev->args[i].name = strdup(buf);
1322		}
1323		if (pev->args[i].name == NULL && ret >= 0)
1324			ret = -ENOMEM;
1325	}
1326
1327	if (ret < 0)
1328		clear_perf_probe_event(pev);
1329
1330	return ret;
1331}
1332
1333void clear_perf_probe_event(struct perf_probe_event *pev)
1334{
1335	struct perf_probe_point *pp = &pev->point;
1336	struct perf_probe_arg_field *field, *next;
1337	int i;
1338
1339	if (pev->event)
1340		free(pev->event);
1341	if (pev->group)
1342		free(pev->group);
1343	if (pp->file)
1344		free(pp->file);
1345	if (pp->function)
1346		free(pp->function);
1347	if (pp->lazy_line)
1348		free(pp->lazy_line);
1349	for (i = 0; i < pev->nargs; i++) {
1350		if (pev->args[i].name)
1351			free(pev->args[i].name);
1352		if (pev->args[i].var)
1353			free(pev->args[i].var);
1354		if (pev->args[i].type)
1355			free(pev->args[i].type);
1356		field = pev->args[i].field;
1357		while (field) {
1358			next = field->next;
1359			if (field->name)
1360				free(field->name);
1361			free(field);
1362			field = next;
1363		}
1364	}
1365	if (pev->args)
1366		free(pev->args);
1367	memset(pev, 0, sizeof(*pev));
1368}
1369
1370static void clear_probe_trace_event(struct probe_trace_event *tev)
1371{
1372	struct probe_trace_arg_ref *ref, *next;
1373	int i;
1374
1375	if (tev->event)
1376		free(tev->event);
1377	if (tev->group)
1378		free(tev->group);
1379	if (tev->point.symbol)
1380		free(tev->point.symbol);
1381	for (i = 0; i < tev->nargs; i++) {
1382		if (tev->args[i].name)
1383			free(tev->args[i].name);
1384		if (tev->args[i].value)
1385			free(tev->args[i].value);
1386		if (tev->args[i].type)
1387			free(tev->args[i].type);
1388		ref = tev->args[i].ref;
1389		while (ref) {
1390			next = ref->next;
1391			free(ref);
1392			ref = next;
1393		}
1394	}
1395	if (tev->args)
1396		free(tev->args);
1397	memset(tev, 0, sizeof(*tev));
1398}
1399
1400static int open_kprobe_events(bool readwrite)
1401{
1402	char buf[PATH_MAX];
1403	const char *__debugfs;
1404	int ret;
1405
1406	__debugfs = debugfs_find_mountpoint();
1407	if (__debugfs == NULL) {
1408		pr_warning("Debugfs is not mounted.\n");
1409		return -ENOENT;
1410	}
1411
1412	ret = e_snprintf(buf, PATH_MAX, "%stracing/kprobe_events", __debugfs);
1413	if (ret >= 0) {
1414		pr_debug("Opening %s write=%d\n", buf, readwrite);
1415		if (readwrite && !probe_event_dry_run)
1416			ret = open(buf, O_RDWR, O_APPEND);
1417		else
1418			ret = open(buf, O_RDONLY, 0);
1419	}
1420
1421	if (ret < 0) {
1422		if (errno == ENOENT)
1423			pr_warning("kprobe_events file does not exist - please"
1424				 " rebuild kernel with CONFIG_KPROBE_EVENT.\n");
1425		else
1426			pr_warning("Failed to open kprobe_events file: %s\n",
1427				   strerror(errno));
1428	}
1429	return ret;
1430}
1431
1432/* Get raw string list of current kprobe_events */
1433static struct strlist *get_probe_trace_command_rawlist(int fd)
1434{
1435	int ret, idx;
1436	FILE *fp;
1437	char buf[MAX_CMDLEN];
1438	char *p;
1439	struct strlist *sl;
1440
1441	sl = strlist__new(true, NULL);
1442
1443	fp = fdopen(dup(fd), "r");
1444	while (!feof(fp)) {
1445		p = fgets(buf, MAX_CMDLEN, fp);
1446		if (!p)
1447			break;
1448
1449		idx = strlen(p) - 1;
1450		if (p[idx] == '\n')
1451			p[idx] = '\0';
1452		ret = strlist__add(sl, buf);
1453		if (ret < 0) {
1454			pr_debug("strlist__add failed: %s\n", strerror(-ret));
1455			strlist__delete(sl);
1456			return NULL;
1457		}
1458	}
1459	fclose(fp);
1460
1461	return sl;
1462}
1463
1464/* Show an event */
1465static int show_perf_probe_event(struct perf_probe_event *pev)
1466{
1467	int i, ret;
1468	char buf[128];
1469	char *place;
1470
1471	/* Synthesize only event probe point */
1472	place = synthesize_perf_probe_point(&pev->point);
1473	if (!place)
1474		return -EINVAL;
1475
1476	ret = e_snprintf(buf, 128, "%s:%s", pev->group, pev->event);
1477	if (ret < 0)
1478		return ret;
1479
1480	printf("  %-20s (on %s", buf, place);
1481
1482	if (pev->nargs > 0) {
1483		printf(" with");
1484		for (i = 0; i < pev->nargs; i++) {
1485			ret = synthesize_perf_probe_arg(&pev->args[i],
1486							buf, 128);
1487			if (ret < 0)
1488				break;
1489			printf(" %s", buf);
1490		}
1491	}
1492	printf(")\n");
1493	free(place);
1494	return ret;
1495}
1496
1497/* List up current perf-probe events */
1498int show_perf_probe_events(void)
1499{
1500	int fd, ret;
1501	struct probe_trace_event tev;
1502	struct perf_probe_event pev;
1503	struct strlist *rawlist;
1504	struct str_node *ent;
1505
1506	setup_pager();
1507	ret = init_vmlinux();
1508	if (ret < 0)
1509		return ret;
1510
1511	memset(&tev, 0, sizeof(tev));
1512	memset(&pev, 0, sizeof(pev));
1513
1514	fd = open_kprobe_events(false);
1515	if (fd < 0)
1516		return fd;
1517
1518	rawlist = get_probe_trace_command_rawlist(fd);
1519	close(fd);
1520	if (!rawlist)
1521		return -ENOENT;
1522
1523	strlist__for_each(ent, rawlist) {
1524		ret = parse_probe_trace_command(ent->s, &tev);
1525		if (ret >= 0) {
1526			ret = convert_to_perf_probe_event(&tev, &pev);
1527			if (ret >= 0)
1528				ret = show_perf_probe_event(&pev);
1529		}
1530		clear_perf_probe_event(&pev);
1531		clear_probe_trace_event(&tev);
1532		if (ret < 0)
1533			break;
1534	}
1535	strlist__delete(rawlist);
1536
1537	return ret;
1538}
1539
1540/* Get current perf-probe event names */
1541static struct strlist *get_probe_trace_event_names(int fd, bool include_group)
1542{
1543	char buf[128];
1544	struct strlist *sl, *rawlist;
1545	struct str_node *ent;
1546	struct probe_trace_event tev;
1547	int ret = 0;
1548
1549	memset(&tev, 0, sizeof(tev));
1550	rawlist = get_probe_trace_command_rawlist(fd);
1551	sl = strlist__new(true, NULL);
1552	strlist__for_each(ent, rawlist) {
1553		ret = parse_probe_trace_command(ent->s, &tev);
1554		if (ret < 0)
1555			break;
1556		if (include_group) {
1557			ret = e_snprintf(buf, 128, "%s:%s", tev.group,
1558					tev.event);
1559			if (ret >= 0)
1560				ret = strlist__add(sl, buf);
1561		} else
1562			ret = strlist__add(sl, tev.event);
1563		clear_probe_trace_event(&tev);
1564		if (ret < 0)
1565			break;
1566	}
1567	strlist__delete(rawlist);
1568
1569	if (ret < 0) {
1570		strlist__delete(sl);
1571		return NULL;
1572	}
1573	return sl;
1574}
1575
1576static int write_probe_trace_event(int fd, struct probe_trace_event *tev)
1577{
1578	int ret = 0;
1579	char *buf = synthesize_probe_trace_command(tev);
1580
1581	if (!buf) {
1582		pr_debug("Failed to synthesize probe trace event.\n");
1583		return -EINVAL;
1584	}
1585
1586	pr_debug("Writing event: %s\n", buf);
1587	if (!probe_event_dry_run) {
1588		ret = write(fd, buf, strlen(buf));
1589		if (ret <= 0)
1590			pr_warning("Failed to write event: %s\n",
1591				   strerror(errno));
1592	}
1593	free(buf);
1594	return ret;
1595}
1596
1597static int get_new_event_name(char *buf, size_t len, const char *base,
1598			      struct strlist *namelist, bool allow_suffix)
1599{
1600	int i, ret;
1601
1602	/* Try no suffix */
1603	ret = e_snprintf(buf, len, "%s", base);
1604	if (ret < 0) {
1605		pr_debug("snprintf() failed: %s\n", strerror(-ret));
1606		return ret;
1607	}
1608	if (!strlist__has_entry(namelist, buf))
1609		return 0;
1610
1611	if (!allow_suffix) {
1612		pr_warning("Error: event \"%s\" already exists. "
1613			   "(Use -f to force duplicates.)\n", base);
1614		return -EEXIST;
1615	}
1616
1617	/* Try to add suffix */
1618	for (i = 1; i < MAX_EVENT_INDEX; i++) {
1619		ret = e_snprintf(buf, len, "%s_%d", base, i);
1620		if (ret < 0) {
1621			pr_debug("snprintf() failed: %s\n", strerror(-ret));
1622			return ret;
1623		}
1624		if (!strlist__has_entry(namelist, buf))
1625			break;
1626	}
1627	if (i == MAX_EVENT_INDEX) {
1628		pr_warning("Too many events are on the same function.\n");
1629		ret = -ERANGE;
1630	}
1631
1632	return ret;
1633}
1634
1635static int __add_probe_trace_events(struct perf_probe_event *pev,
1636				     struct probe_trace_event *tevs,
1637				     int ntevs, bool allow_suffix)
1638{
1639	int i, fd, ret;
1640	struct probe_trace_event *tev = NULL;
1641	char buf[64];
1642	const char *event, *group;
1643	struct strlist *namelist;
1644
1645	fd = open_kprobe_events(true);
1646	if (fd < 0)
1647		return fd;
1648	/* Get current event names */
1649	namelist = get_probe_trace_event_names(fd, false);
1650	if (!namelist) {
1651		pr_debug("Failed to get current event list.\n");
1652		return -EIO;
1653	}
1654
1655	ret = 0;
1656	printf("Add new event%s\n", (ntevs > 1) ? "s:" : ":");
1657	for (i = 0; i < ntevs; i++) {
1658		tev = &tevs[i];
1659		if (pev->event)
1660			event = pev->event;
1661		else
1662			if (pev->point.function)
1663				event = pev->point.function;
1664			else
1665				event = tev->point.symbol;
1666		if (pev->group)
1667			group = pev->group;
1668		else
1669			group = PERFPROBE_GROUP;
1670
1671		/* Get an unused new event name */
1672		ret = get_new_event_name(buf, 64, event,
1673					 namelist, allow_suffix);
1674		if (ret < 0)
1675			break;
1676		event = buf;
1677
1678		tev->event = strdup(event);
1679		tev->group = strdup(group);
1680		if (tev->event == NULL || tev->group == NULL) {
1681			ret = -ENOMEM;
1682			break;
1683		}
1684		ret = write_probe_trace_event(fd, tev);
1685		if (ret < 0)
1686			break;
1687		/* Add added event name to namelist */
1688		strlist__add(namelist, event);
1689
1690		/* Trick here - save current event/group */
1691		event = pev->event;
1692		group = pev->group;
1693		pev->event = tev->event;
1694		pev->group = tev->group;
1695		show_perf_probe_event(pev);
1696		/* Trick here - restore current event/group */
1697		pev->event = (char *)event;
1698		pev->group = (char *)group;
1699
1700		/*
1701		 * Probes after the first probe which comes from same
1702		 * user input are always allowed to add suffix, because
1703		 * there might be several addresses corresponding to
1704		 * one code line.
1705		 */
1706		allow_suffix = true;
1707	}
1708
1709	if (ret >= 0) {
1710		/* Show how to use the event. */
1711		printf("\nYou can now use it on all perf tools, such as:\n\n");
1712		printf("\tperf record -e %s:%s -aR sleep 1\n\n", tev->group,
1713			 tev->event);
1714	}
1715
1716	strlist__delete(namelist);
1717	close(fd);
1718	return ret;
1719}
1720
1721static int convert_to_probe_trace_events(struct perf_probe_event *pev,
1722					  struct probe_trace_event **tevs,
1723					  int max_tevs, const char *module)
1724{
1725	struct symbol *sym;
1726	int ret = 0, i;
1727	struct probe_trace_event *tev;
1728
1729	/* Convert perf_probe_event with debuginfo */
1730	ret = try_to_find_probe_trace_events(pev, tevs, max_tevs, module);
1731	if (ret != 0)
1732		return ret;
1733
1734	/* Allocate trace event buffer */
1735	tev = *tevs = zalloc(sizeof(struct probe_trace_event));
1736	if (tev == NULL)
1737		return -ENOMEM;
1738
1739	/* Copy parameters */
1740	tev->point.symbol = strdup(pev->point.function);
1741	if (tev->point.symbol == NULL) {
1742		ret = -ENOMEM;
1743		goto error;
1744	}
1745	tev->point.offset = pev->point.offset;
1746	tev->point.retprobe = pev->point.retprobe;
1747	tev->nargs = pev->nargs;
1748	if (tev->nargs) {
1749		tev->args = zalloc(sizeof(struct probe_trace_arg)
1750				   * tev->nargs);
1751		if (tev->args == NULL) {
1752			ret = -ENOMEM;
1753			goto error;
1754		}
1755		for (i = 0; i < tev->nargs; i++) {
1756			if (pev->args[i].name) {
1757				tev->args[i].name = strdup(pev->args[i].name);
1758				if (tev->args[i].name == NULL) {
1759					ret = -ENOMEM;
1760					goto error;
1761				}
1762			}
1763			tev->args[i].value = strdup(pev->args[i].var);
1764			if (tev->args[i].value == NULL) {
1765				ret = -ENOMEM;
1766				goto error;
1767			}
1768			if (pev->args[i].type) {
1769				tev->args[i].type = strdup(pev->args[i].type);
1770				if (tev->args[i].type == NULL) {
1771					ret = -ENOMEM;
1772					goto error;
1773				}
1774			}
1775		}
1776	}
1777
1778	/* Currently just checking function name from symbol map */
1779	sym = __find_kernel_function_by_name(tev->point.symbol, NULL);
1780	if (!sym) {
1781		pr_warning("Kernel symbol \'%s\' not found.\n",
1782			   tev->point.symbol);
1783		ret = -ENOENT;
1784		goto error;
1785	}
1786
1787	return 1;
1788error:
1789	clear_probe_trace_event(tev);
1790	free(tev);
1791	*tevs = NULL;
1792	return ret;
1793}
1794
1795struct __event_package {
1796	struct perf_probe_event		*pev;
1797	struct probe_trace_event	*tevs;
1798	int				ntevs;
1799};
1800
1801int add_perf_probe_events(struct perf_probe_event *pevs, int npevs,
1802			  int max_tevs, const char *module, bool force_add)
1803{
1804	int i, j, ret;
1805	struct __event_package *pkgs;
1806
1807	pkgs = zalloc(sizeof(struct __event_package) * npevs);
1808	if (pkgs == NULL)
1809		return -ENOMEM;
1810
1811	/* Init vmlinux path */
1812	ret = init_vmlinux();
1813	if (ret < 0) {
1814		free(pkgs);
1815		return ret;
1816	}
1817
1818	/* Loop 1: convert all events */
1819	for (i = 0; i < npevs; i++) {
1820		pkgs[i].pev = &pevs[i];
1821		/* Convert with or without debuginfo */
1822		ret  = convert_to_probe_trace_events(pkgs[i].pev,
1823						     &pkgs[i].tevs,
1824						     max_tevs,
1825						     module);
1826		if (ret < 0)
1827			goto end;
1828		pkgs[i].ntevs = ret;
1829	}
1830
1831	/* Loop 2: add all events */
1832	for (i = 0; i < npevs; i++) {
1833		ret = __add_probe_trace_events(pkgs[i].pev, pkgs[i].tevs,
1834						pkgs[i].ntevs, force_add);
1835		if (ret < 0)
1836			break;
1837	}
1838end:
1839	/* Loop 3: cleanup and free trace events  */
1840	for (i = 0; i < npevs; i++) {
1841		for (j = 0; j < pkgs[i].ntevs; j++)
1842			clear_probe_trace_event(&pkgs[i].tevs[j]);
1843		free(pkgs[i].tevs);
1844	}
1845	free(pkgs);
1846
1847	return ret;
1848}
1849
1850static int __del_trace_probe_event(int fd, struct str_node *ent)
1851{
1852	char *p;
1853	char buf[128];
1854	int ret;
1855
1856	/* Convert from perf-probe event to trace-probe event */
1857	ret = e_snprintf(buf, 128, "-:%s", ent->s);
1858	if (ret < 0)
1859		goto error;
1860
1861	p = strchr(buf + 2, ':');
1862	if (!p) {
1863		pr_debug("Internal error: %s should have ':' but not.\n",
1864			 ent->s);
1865		ret = -ENOTSUP;
1866		goto error;
1867	}
1868	*p = '/';
1869
1870	pr_debug("Writing event: %s\n", buf);
1871	ret = write(fd, buf, strlen(buf));
1872	if (ret < 0)
1873		goto error;
1874
1875	printf("Remove event: %s\n", ent->s);
1876	return 0;
1877error:
1878	pr_warning("Failed to delete event: %s\n", strerror(-ret));
1879	return ret;
1880}
1881
1882static int del_trace_probe_event(int fd, const char *group,
1883				  const char *event, struct strlist *namelist)
1884{
1885	char buf[128];
1886	struct str_node *ent, *n;
1887	int found = 0, ret = 0;
1888
1889	ret = e_snprintf(buf, 128, "%s:%s", group, event);
1890	if (ret < 0) {
1891		pr_err("Failed to copy event.\n");
1892		return ret;
1893	}
1894
1895	if (strpbrk(buf, "*?")) { /* Glob-exp */
1896		strlist__for_each_safe(ent, n, namelist)
1897			if (strglobmatch(ent->s, buf)) {
1898				found++;
1899				ret = __del_trace_probe_event(fd, ent);
1900				if (ret < 0)
1901					break;
1902				strlist__remove(namelist, ent);
1903			}
1904	} else {
1905		ent = strlist__find(namelist, buf);
1906		if (ent) {
1907			found++;
1908			ret = __del_trace_probe_event(fd, ent);
1909			if (ret >= 0)
1910				strlist__remove(namelist, ent);
1911		}
1912	}
1913	if (found == 0 && ret >= 0)
1914		pr_info("Info: Event \"%s\" does not exist.\n", buf);
1915
1916	return ret;
1917}
1918
1919int del_perf_probe_events(struct strlist *dellist)
1920{
1921	int fd, ret = 0;
1922	const char *group, *event;
1923	char *p, *str;
1924	struct str_node *ent;
1925	struct strlist *namelist;
1926
1927	fd = open_kprobe_events(true);
1928	if (fd < 0)
1929		return fd;
1930
1931	/* Get current event names */
1932	namelist = get_probe_trace_event_names(fd, true);
1933	if (namelist == NULL)
1934		return -EINVAL;
1935
1936	strlist__for_each(ent, dellist) {
1937		str = strdup(ent->s);
1938		if (str == NULL) {
1939			ret = -ENOMEM;
1940			break;
1941		}
1942		pr_debug("Parsing: %s\n", str);
1943		p = strchr(str, ':');
1944		if (p) {
1945			group = str;
1946			*p = '\0';
1947			event = p + 1;
1948		} else {
1949			group = "*";
1950			event = str;
1951		}
1952		pr_debug("Group: %s, Event: %s\n", group, event);
1953		ret = del_trace_probe_event(fd, group, event, namelist);
1954		free(str);
1955		if (ret < 0)
1956			break;
1957	}
1958	strlist__delete(namelist);
1959	close(fd);
1960
1961	return ret;
1962}
1963/* TODO: don't use a global variable for filter ... */
1964static struct strfilter *available_func_filter;
1965
1966/*
1967 * If a symbol corresponds to a function with global binding and
1968 * matches filter return 0. For all others return 1.
1969 */
1970static int filter_available_functions(struct map *map __unused,
1971				      struct symbol *sym)
1972{
1973	if (sym->binding == STB_GLOBAL &&
1974	    strfilter__compare(available_func_filter, sym->name))
1975		return 0;
1976	return 1;
1977}
1978
1979int show_available_funcs(const char *module, struct strfilter *_filter)
1980{
1981	struct map *map;
1982	int ret;
1983
1984	setup_pager();
1985
1986	ret = init_vmlinux();
1987	if (ret < 0)
1988		return ret;
1989
1990	map = kernel_get_module_map(module);
1991	if (!map) {
1992		pr_err("Failed to find %s map.\n", (module) ? : "kernel");
1993		return -EINVAL;
1994	}
1995	available_func_filter = _filter;
1996	if (map__load(map, filter_available_functions)) {
1997		pr_err("Failed to load map.\n");
1998		return -EINVAL;
1999	}
2000	if (!dso__sorted_by_name(map->dso, map->type))
2001		dso__sort_by_name(map->dso, map->type);
2002
2003	dso__fprintf_symbols_by_name(map->dso, map->type, stdout);
2004	return 0;
2005}
2006