perf probe: Fix to copy the type for raw parameters
[linux-2.6.git] / tools / perf / util / probe-finder.c
1 /*
2  * probe-finder.c : C expression to kprobe event 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 #include <sys/utsname.h>
23 #include <sys/types.h>
24 #include <sys/stat.h>
25 #include <fcntl.h>
26 #include <errno.h>
27 #include <stdio.h>
28 #include <unistd.h>
29 #include <getopt.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <stdarg.h>
33 #include <ctype.h>
34 #include <dwarf-regs.h>
35
36 #include "event.h"
37 #include "debug.h"
38 #include "util.h"
39 #include "symbol.h"
40 #include "probe-finder.h"
41
42 /* Kprobe tracer basic type is up to u64 */
43 #define MAX_BASIC_TYPE_BITS     64
44
45 /*
46  * Compare the tail of two strings.
47  * Return 0 if whole of either string is same as another's tail part.
48  */
49 static int strtailcmp(const char *s1, const char *s2)
50 {
51         int i1 = strlen(s1);
52         int i2 = strlen(s2);
53         while (--i1 >= 0 && --i2 >= 0) {
54                 if (s1[i1] != s2[i2])
55                         return s1[i1] - s2[i2];
56         }
57         return 0;
58 }
59
60 /* Line number list operations */
61
62 /* Add a line to line number list */
63 static int line_list__add_line(struct list_head *head, int line)
64 {
65         struct line_node *ln;
66         struct list_head *p;
67
68         /* Reverse search, because new line will be the last one */
69         list_for_each_entry_reverse(ln, head, list) {
70                 if (ln->line < line) {
71                         p = &ln->list;
72                         goto found;
73                 } else if (ln->line == line)    /* Already exist */
74                         return 1;
75         }
76         /* List is empty, or the smallest entry */
77         p = head;
78 found:
79         pr_debug("line list: add a line %u\n", line);
80         ln = zalloc(sizeof(struct line_node));
81         if (ln == NULL)
82                 return -ENOMEM;
83         ln->line = line;
84         INIT_LIST_HEAD(&ln->list);
85         list_add(&ln->list, p);
86         return 0;
87 }
88
89 /* Check if the line in line number list */
90 static int line_list__has_line(struct list_head *head, int line)
91 {
92         struct line_node *ln;
93
94         /* Reverse search, because new line will be the last one */
95         list_for_each_entry(ln, head, list)
96                 if (ln->line == line)
97                         return 1;
98
99         return 0;
100 }
101
102 /* Init line number list */
103 static void line_list__init(struct list_head *head)
104 {
105         INIT_LIST_HEAD(head);
106 }
107
108 /* Free line number list */
109 static void line_list__free(struct list_head *head)
110 {
111         struct line_node *ln;
112         while (!list_empty(head)) {
113                 ln = list_first_entry(head, struct line_node, list);
114                 list_del(&ln->list);
115                 free(ln);
116         }
117 }
118
119 /* Dwarf wrappers */
120
121 /* Find the realpath of the target file. */
122 static const char *cu_find_realpath(Dwarf_Die *cu_die, const char *fname)
123 {
124         Dwarf_Files *files;
125         size_t nfiles, i;
126         const char *src = NULL;
127         int ret;
128
129         if (!fname)
130                 return NULL;
131
132         ret = dwarf_getsrcfiles(cu_die, &files, &nfiles);
133         if (ret != 0)
134                 return NULL;
135
136         for (i = 0; i < nfiles; i++) {
137                 src = dwarf_filesrc(files, i, NULL, NULL);
138                 if (strtailcmp(src, fname) == 0)
139                         break;
140         }
141         if (i == nfiles)
142                 return NULL;
143         return src;
144 }
145
146 /* Get DW_AT_comp_dir (should be NULL with older gcc) */
147 static const char *cu_get_comp_dir(Dwarf_Die *cu_die)
148 {
149         Dwarf_Attribute attr;
150         if (dwarf_attr(cu_die, DW_AT_comp_dir, &attr) == NULL)
151                 return NULL;
152         return dwarf_formstring(&attr);
153 }
154
155 /* Compare diename and tname */
156 static bool die_compare_name(Dwarf_Die *dw_die, const char *tname)
157 {
158         const char *name;
159         name = dwarf_diename(dw_die);
160         return name ? (strcmp(tname, name) == 0) : false;
161 }
162
163 /* Get type die, but skip qualifiers and typedef */
164 static Dwarf_Die *die_get_real_type(Dwarf_Die *vr_die, Dwarf_Die *die_mem)
165 {
166         Dwarf_Attribute attr;
167         int tag;
168
169         do {
170                 if (dwarf_attr(vr_die, DW_AT_type, &attr) == NULL ||
171                     dwarf_formref_die(&attr, die_mem) == NULL)
172                         return NULL;
173
174                 tag = dwarf_tag(die_mem);
175                 vr_die = die_mem;
176         } while (tag == DW_TAG_const_type ||
177                  tag == DW_TAG_restrict_type ||
178                  tag == DW_TAG_volatile_type ||
179                  tag == DW_TAG_shared_type ||
180                  tag == DW_TAG_typedef);
181
182         return die_mem;
183 }
184
185 static bool die_is_signed_type(Dwarf_Die *tp_die)
186 {
187         Dwarf_Attribute attr;
188         Dwarf_Word ret;
189
190         if (dwarf_attr(tp_die, DW_AT_encoding, &attr) == NULL ||
191             dwarf_formudata(&attr, &ret) != 0)
192                 return false;
193
194         return (ret == DW_ATE_signed_char || ret == DW_ATE_signed ||
195                 ret == DW_ATE_signed_fixed);
196 }
197
198 static int die_get_byte_size(Dwarf_Die *tp_die)
199 {
200         Dwarf_Attribute attr;
201         Dwarf_Word ret;
202
203         if (dwarf_attr(tp_die, DW_AT_byte_size, &attr) == NULL ||
204             dwarf_formudata(&attr, &ret) != 0)
205                 return 0;
206
207         return (int)ret;
208 }
209
210 /* Get data_member_location offset */
211 static int die_get_data_member_location(Dwarf_Die *mb_die, Dwarf_Word *offs)
212 {
213         Dwarf_Attribute attr;
214         Dwarf_Op *expr;
215         size_t nexpr;
216         int ret;
217
218         if (dwarf_attr(mb_die, DW_AT_data_member_location, &attr) == NULL)
219                 return -ENOENT;
220
221         if (dwarf_formudata(&attr, offs) != 0) {
222                 /* DW_AT_data_member_location should be DW_OP_plus_uconst */
223                 ret = dwarf_getlocation(&attr, &expr, &nexpr);
224                 if (ret < 0 || nexpr == 0)
225                         return -ENOENT;
226
227                 if (expr[0].atom != DW_OP_plus_uconst || nexpr != 1) {
228                         pr_debug("Unable to get offset:Unexpected OP %x (%zd)\n",
229                                  expr[0].atom, nexpr);
230                         return -ENOTSUP;
231                 }
232                 *offs = (Dwarf_Word)expr[0].number;
233         }
234         return 0;
235 }
236
237 /* Return values for die_find callbacks */
238 enum {
239         DIE_FIND_CB_FOUND = 0,          /* End of Search */
240         DIE_FIND_CB_CHILD = 1,          /* Search only children */
241         DIE_FIND_CB_SIBLING = 2,        /* Search only siblings */
242         DIE_FIND_CB_CONTINUE = 3,       /* Search children and siblings */
243 };
244
245 /* Search a child die */
246 static Dwarf_Die *die_find_child(Dwarf_Die *rt_die,
247                                  int (*callback)(Dwarf_Die *, void *),
248                                  void *data, Dwarf_Die *die_mem)
249 {
250         Dwarf_Die child_die;
251         int ret;
252
253         ret = dwarf_child(rt_die, die_mem);
254         if (ret != 0)
255                 return NULL;
256
257         do {
258                 ret = callback(die_mem, data);
259                 if (ret == DIE_FIND_CB_FOUND)
260                         return die_mem;
261
262                 if ((ret & DIE_FIND_CB_CHILD) &&
263                     die_find_child(die_mem, callback, data, &child_die)) {
264                         memcpy(die_mem, &child_die, sizeof(Dwarf_Die));
265                         return die_mem;
266                 }
267         } while ((ret & DIE_FIND_CB_SIBLING) &&
268                  dwarf_siblingof(die_mem, die_mem) == 0);
269
270         return NULL;
271 }
272
273 struct __addr_die_search_param {
274         Dwarf_Addr      addr;
275         Dwarf_Die       *die_mem;
276 };
277
278 static int __die_search_func_cb(Dwarf_Die *fn_die, void *data)
279 {
280         struct __addr_die_search_param *ad = data;
281
282         if (dwarf_tag(fn_die) == DW_TAG_subprogram &&
283             dwarf_haspc(fn_die, ad->addr)) {
284                 memcpy(ad->die_mem, fn_die, sizeof(Dwarf_Die));
285                 return DWARF_CB_ABORT;
286         }
287         return DWARF_CB_OK;
288 }
289
290 /* Search a real subprogram including this line, */
291 static Dwarf_Die *die_find_real_subprogram(Dwarf_Die *cu_die, Dwarf_Addr addr,
292                                            Dwarf_Die *die_mem)
293 {
294         struct __addr_die_search_param ad;
295         ad.addr = addr;
296         ad.die_mem = die_mem;
297         /* dwarf_getscopes can't find subprogram. */
298         if (!dwarf_getfuncs(cu_die, __die_search_func_cb, &ad, 0))
299                 return NULL;
300         else
301                 return die_mem;
302 }
303
304 /* die_find callback for inline function search */
305 static int __die_find_inline_cb(Dwarf_Die *die_mem, void *data)
306 {
307         Dwarf_Addr *addr = data;
308
309         if (dwarf_tag(die_mem) == DW_TAG_inlined_subroutine &&
310             dwarf_haspc(die_mem, *addr))
311                 return DIE_FIND_CB_FOUND;
312
313         return DIE_FIND_CB_CONTINUE;
314 }
315
316 /* Similar to dwarf_getfuncs, but returns inlined_subroutine if exists. */
317 static Dwarf_Die *die_find_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
318                                       Dwarf_Die *die_mem)
319 {
320         return die_find_child(sp_die, __die_find_inline_cb, &addr, die_mem);
321 }
322
323 static int __die_find_variable_cb(Dwarf_Die *die_mem, void *data)
324 {
325         const char *name = data;
326         int tag;
327
328         tag = dwarf_tag(die_mem);
329         if ((tag == DW_TAG_formal_parameter ||
330              tag == DW_TAG_variable) &&
331             die_compare_name(die_mem, name))
332                 return DIE_FIND_CB_FOUND;
333
334         return DIE_FIND_CB_CONTINUE;
335 }
336
337 /* Find a variable called 'name' */
338 static Dwarf_Die *die_find_variable(Dwarf_Die *sp_die, const char *name,
339                                     Dwarf_Die *die_mem)
340 {
341         return die_find_child(sp_die, __die_find_variable_cb, (void *)name,
342                               die_mem);
343 }
344
345 static int __die_find_member_cb(Dwarf_Die *die_mem, void *data)
346 {
347         const char *name = data;
348
349         if ((dwarf_tag(die_mem) == DW_TAG_member) &&
350             die_compare_name(die_mem, name))
351                 return DIE_FIND_CB_FOUND;
352
353         return DIE_FIND_CB_SIBLING;
354 }
355
356 /* Find a member called 'name' */
357 static Dwarf_Die *die_find_member(Dwarf_Die *st_die, const char *name,
358                                   Dwarf_Die *die_mem)
359 {
360         return die_find_child(st_die, __die_find_member_cb, (void *)name,
361                               die_mem);
362 }
363
364 /*
365  * Probe finder related functions
366  */
367
368 static struct probe_trace_arg_ref *alloc_trace_arg_ref(long offs)
369 {
370         struct probe_trace_arg_ref *ref;
371         ref = zalloc(sizeof(struct probe_trace_arg_ref));
372         if (ref != NULL)
373                 ref->offset = offs;
374         return ref;
375 }
376
377 /* Show a location */
378 static int convert_variable_location(Dwarf_Die *vr_die, struct probe_finder *pf)
379 {
380         Dwarf_Attribute attr;
381         Dwarf_Op *op;
382         size_t nops;
383         unsigned int regn;
384         Dwarf_Word offs = 0;
385         bool ref = false;
386         const char *regs;
387         struct probe_trace_arg *tvar = pf->tvar;
388         int ret;
389
390         /* TODO: handle more than 1 exprs */
391         if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL ||
392             dwarf_getlocation_addr(&attr, pf->addr, &op, &nops, 1) <= 0 ||
393             nops == 0) {
394                 /* TODO: Support const_value */
395                 pr_err("Failed to find the location of %s at this address.\n"
396                        " Perhaps, it has been optimized out.\n", pf->pvar->var);
397                 return -ENOENT;
398         }
399
400         if (op->atom == DW_OP_addr) {
401                 /* Static variables on memory (not stack), make @varname */
402                 ret = strlen(dwarf_diename(vr_die));
403                 tvar->value = zalloc(ret + 2);
404                 if (tvar->value == NULL)
405                         return -ENOMEM;
406                 snprintf(tvar->value, ret + 2, "@%s", dwarf_diename(vr_die));
407                 tvar->ref = alloc_trace_arg_ref((long)offs);
408                 if (tvar->ref == NULL)
409                         return -ENOMEM;
410                 return 0;
411         }
412
413         /* If this is based on frame buffer, set the offset */
414         if (op->atom == DW_OP_fbreg) {
415                 if (pf->fb_ops == NULL) {
416                         pr_warning("The attribute of frame base is not "
417                                    "supported.\n");
418                         return -ENOTSUP;
419                 }
420                 ref = true;
421                 offs = op->number;
422                 op = &pf->fb_ops[0];
423         }
424
425         if (op->atom >= DW_OP_breg0 && op->atom <= DW_OP_breg31) {
426                 regn = op->atom - DW_OP_breg0;
427                 offs += op->number;
428                 ref = true;
429         } else if (op->atom >= DW_OP_reg0 && op->atom <= DW_OP_reg31) {
430                 regn = op->atom - DW_OP_reg0;
431         } else if (op->atom == DW_OP_bregx) {
432                 regn = op->number;
433                 offs += op->number2;
434                 ref = true;
435         } else if (op->atom == DW_OP_regx) {
436                 regn = op->number;
437         } else {
438                 pr_warning("DW_OP %x is not supported.\n", op->atom);
439                 return -ENOTSUP;
440         }
441
442         regs = get_arch_regstr(regn);
443         if (!regs) {
444                 pr_warning("Mapping for DWARF register number %u missing on this architecture.", regn);
445                 return -ERANGE;
446         }
447
448         tvar->value = strdup(regs);
449         if (tvar->value == NULL)
450                 return -ENOMEM;
451
452         if (ref) {
453                 tvar->ref = alloc_trace_arg_ref((long)offs);
454                 if (tvar->ref == NULL)
455                         return -ENOMEM;
456         }
457         return 0;
458 }
459
460 static int convert_variable_type(Dwarf_Die *vr_die,
461                                  struct probe_trace_arg *tvar,
462                                  const char *cast)
463 {
464         struct probe_trace_arg_ref **ref_ptr = &tvar->ref;
465         Dwarf_Die type;
466         char buf[16];
467         int ret;
468
469         /* TODO: check all types */
470         if (cast && strcmp(cast, "string") != 0) {
471                 /* Non string type is OK */
472                 tvar->type = strdup(cast);
473                 return (tvar->type == NULL) ? -ENOMEM : 0;
474         }
475
476         if (die_get_real_type(vr_die, &type) == NULL) {
477                 pr_warning("Failed to get a type information of %s.\n",
478                            dwarf_diename(vr_die));
479                 return -ENOENT;
480         }
481
482         pr_debug("%s type is %s.\n",
483                  dwarf_diename(vr_die), dwarf_diename(&type));
484
485         if (cast && strcmp(cast, "string") == 0) {      /* String type */
486                 ret = dwarf_tag(&type);
487                 if (ret != DW_TAG_pointer_type &&
488                     ret != DW_TAG_array_type) {
489                         pr_warning("Failed to cast into string: "
490                                    "%s(%s) is not a pointer nor array.",
491                                    dwarf_diename(vr_die), dwarf_diename(&type));
492                         return -EINVAL;
493                 }
494                 if (ret == DW_TAG_pointer_type) {
495                         if (die_get_real_type(&type, &type) == NULL) {
496                                 pr_warning("Failed to get a type information.");
497                                 return -ENOENT;
498                         }
499                         while (*ref_ptr)
500                                 ref_ptr = &(*ref_ptr)->next;
501                         /* Add new reference with offset +0 */
502                         *ref_ptr = zalloc(sizeof(struct probe_trace_arg_ref));
503                         if (*ref_ptr == NULL) {
504                                 pr_warning("Out of memory error\n");
505                                 return -ENOMEM;
506                         }
507                 }
508                 if (!die_compare_name(&type, "char") &&
509                     !die_compare_name(&type, "unsigned char")) {
510                         pr_warning("Failed to cast into string: "
511                                    "%s is not (unsigned) char *.",
512                                    dwarf_diename(vr_die));
513                         return -EINVAL;
514                 }
515                 tvar->type = strdup(cast);
516                 return (tvar->type == NULL) ? -ENOMEM : 0;
517         }
518
519         ret = die_get_byte_size(&type) * 8;
520         if (ret) {
521                 /* Check the bitwidth */
522                 if (ret > MAX_BASIC_TYPE_BITS) {
523                         pr_info("%s exceeds max-bitwidth."
524                                 " Cut down to %d bits.\n",
525                                 dwarf_diename(&type), MAX_BASIC_TYPE_BITS);
526                         ret = MAX_BASIC_TYPE_BITS;
527                 }
528
529                 ret = snprintf(buf, 16, "%c%d",
530                                die_is_signed_type(&type) ? 's' : 'u', ret);
531                 if (ret < 0 || ret >= 16) {
532                         if (ret >= 16)
533                                 ret = -E2BIG;
534                         pr_warning("Failed to convert variable type: %s\n",
535                                    strerror(-ret));
536                         return ret;
537                 }
538                 tvar->type = strdup(buf);
539                 if (tvar->type == NULL)
540                         return -ENOMEM;
541         }
542         return 0;
543 }
544
545 static int convert_variable_fields(Dwarf_Die *vr_die, const char *varname,
546                                     struct perf_probe_arg_field *field,
547                                     struct probe_trace_arg_ref **ref_ptr,
548                                     Dwarf_Die *die_mem)
549 {
550         struct probe_trace_arg_ref *ref = *ref_ptr;
551         Dwarf_Die type;
552         Dwarf_Word offs;
553         int ret, tag;
554
555         pr_debug("converting %s in %s\n", field->name, varname);
556         if (die_get_real_type(vr_die, &type) == NULL) {
557                 pr_warning("Failed to get the type of %s.\n", varname);
558                 return -ENOENT;
559         }
560         pr_debug2("Var real type: (%x)\n", (unsigned)dwarf_dieoffset(&type));
561         tag = dwarf_tag(&type);
562
563         if (field->name[0] == '[' &&
564             (tag == DW_TAG_array_type || tag == DW_TAG_pointer_type)) {
565                 if (field->next)
566                         /* Save original type for next field */
567                         memcpy(die_mem, &type, sizeof(*die_mem));
568                 /* Get the type of this array */
569                 if (die_get_real_type(&type, &type) == NULL) {
570                         pr_warning("Failed to get the type of %s.\n", varname);
571                         return -ENOENT;
572                 }
573                 pr_debug2("Array real type: (%x)\n",
574                          (unsigned)dwarf_dieoffset(&type));
575                 if (tag == DW_TAG_pointer_type) {
576                         ref = zalloc(sizeof(struct probe_trace_arg_ref));
577                         if (ref == NULL)
578                                 return -ENOMEM;
579                         if (*ref_ptr)
580                                 (*ref_ptr)->next = ref;
581                         else
582                                 *ref_ptr = ref;
583                 }
584                 ref->offset += die_get_byte_size(&type) * field->index;
585                 if (!field->next)
586                         /* Save vr_die for converting types */
587                         memcpy(die_mem, vr_die, sizeof(*die_mem));
588                 goto next;
589         } else if (tag == DW_TAG_pointer_type) {
590                 /* Check the pointer and dereference */
591                 if (!field->ref) {
592                         pr_err("Semantic error: %s must be referred by '->'\n",
593                                field->name);
594                         return -EINVAL;
595                 }
596                 /* Get the type pointed by this pointer */
597                 if (die_get_real_type(&type, &type) == NULL) {
598                         pr_warning("Failed to get the type of %s.\n", varname);
599                         return -ENOENT;
600                 }
601                 /* Verify it is a data structure  */
602                 if (dwarf_tag(&type) != DW_TAG_structure_type) {
603                         pr_warning("%s is not a data structure.\n", varname);
604                         return -EINVAL;
605                 }
606
607                 ref = zalloc(sizeof(struct probe_trace_arg_ref));
608                 if (ref == NULL)
609                         return -ENOMEM;
610                 if (*ref_ptr)
611                         (*ref_ptr)->next = ref;
612                 else
613                         *ref_ptr = ref;
614         } else {
615                 /* Verify it is a data structure  */
616                 if (tag != DW_TAG_structure_type) {
617                         pr_warning("%s is not a data structure.\n", varname);
618                         return -EINVAL;
619                 }
620                 if (field->name[0] == '[') {
621                         pr_err("Semantic error: %s is not a pointor nor array.",
622                                varname);
623                         return -EINVAL;
624                 }
625                 if (field->ref) {
626                         pr_err("Semantic error: %s must be referred by '.'\n",
627                                field->name);
628                         return -EINVAL;
629                 }
630                 if (!ref) {
631                         pr_warning("Structure on a register is not "
632                                    "supported yet.\n");
633                         return -ENOTSUP;
634                 }
635         }
636
637         if (die_find_member(&type, field->name, die_mem) == NULL) {
638                 pr_warning("%s(tyep:%s) has no member %s.\n", varname,
639                            dwarf_diename(&type), field->name);
640                 return -EINVAL;
641         }
642
643         /* Get the offset of the field */
644         ret = die_get_data_member_location(die_mem, &offs);
645         if (ret < 0) {
646                 pr_warning("Failed to get the offset of %s.\n", field->name);
647                 return ret;
648         }
649         ref->offset += (long)offs;
650
651 next:
652         /* Converting next field */
653         if (field->next)
654                 return convert_variable_fields(die_mem, field->name,
655                                         field->next, &ref, die_mem);
656         else
657                 return 0;
658 }
659
660 /* Show a variables in kprobe event format */
661 static int convert_variable(Dwarf_Die *vr_die, struct probe_finder *pf)
662 {
663         Dwarf_Die die_mem;
664         int ret;
665
666         pr_debug("Converting variable %s into trace event.\n",
667                  dwarf_diename(vr_die));
668
669         ret = convert_variable_location(vr_die, pf);
670         if (ret == 0 && pf->pvar->field) {
671                 ret = convert_variable_fields(vr_die, pf->pvar->var,
672                                               pf->pvar->field, &pf->tvar->ref,
673                                               &die_mem);
674                 vr_die = &die_mem;
675         }
676         if (ret == 0)
677                 ret = convert_variable_type(vr_die, pf->tvar, pf->pvar->type);
678         /* *expr will be cached in libdw. Don't free it. */
679         return ret;
680 }
681
682 /* Find a variable in a subprogram die */
683 static int find_variable(Dwarf_Die *sp_die, struct probe_finder *pf)
684 {
685         Dwarf_Die vr_die, *scopes;
686         char buf[32], *ptr;
687         int ret, nscopes;
688
689         if (pf->pvar->name)
690                 pf->tvar->name = strdup(pf->pvar->name);
691         else {
692                 ret = synthesize_perf_probe_arg(pf->pvar, buf, 32);
693                 if (ret < 0)
694                         return ret;
695                 ptr = strchr(buf, ':'); /* Change type separator to _ */
696                 if (ptr)
697                         *ptr = '_';
698                 pf->tvar->name = strdup(buf);
699         }
700         if (pf->tvar->name == NULL)
701                 return -ENOMEM;
702
703         if (!is_c_varname(pf->pvar->var)) {
704                 /* Copy raw parameters */
705                 pf->tvar->value = strdup(pf->pvar->var);
706                 if (pf->tvar->value == NULL)
707                         return -ENOMEM;
708                 if (pf->pvar->type) {
709                         pf->tvar->type = strdup(pf->pvar->type);
710                         if (pf->tvar->type == NULL)
711                                 return -ENOMEM;
712                 }
713                 return 0;
714         }
715
716         pr_debug("Searching '%s' variable in context.\n",
717                  pf->pvar->var);
718         /* Search child die for local variables and parameters. */
719         if (die_find_variable(sp_die, pf->pvar->var, &vr_die))
720                 ret = convert_variable(&vr_die, pf);
721         else {
722                 /* Search upper class */
723                 nscopes = dwarf_getscopes_die(sp_die, &scopes);
724                 if (nscopes > 0) {
725                         ret = dwarf_getscopevar(scopes, nscopes, pf->pvar->var,
726                                                 0, NULL, 0, 0, &vr_die);
727                         if (ret >= 0)
728                                 ret = convert_variable(&vr_die, pf);
729                         else
730                                 ret = -ENOENT;
731                         free(scopes);
732                 } else
733                         ret = -ENOENT;
734         }
735         if (ret < 0)
736                 pr_warning("Failed to find '%s' in this function.\n",
737                            pf->pvar->var);
738         return ret;
739 }
740
741 /* Show a probe point to output buffer */
742 static int convert_probe_point(Dwarf_Die *sp_die, struct probe_finder *pf)
743 {
744         struct probe_trace_event *tev;
745         Dwarf_Addr eaddr;
746         Dwarf_Die die_mem;
747         const char *name;
748         int ret, i;
749         Dwarf_Attribute fb_attr;
750         size_t nops;
751
752         if (pf->ntevs == pf->max_tevs) {
753                 pr_warning("Too many( > %d) probe point found.\n",
754                            pf->max_tevs);
755                 return -ERANGE;
756         }
757         tev = &pf->tevs[pf->ntevs++];
758
759         /* If no real subprogram, find a real one */
760         if (!sp_die || dwarf_tag(sp_die) != DW_TAG_subprogram) {
761                 sp_die = die_find_real_subprogram(&pf->cu_die,
762                                                  pf->addr, &die_mem);
763                 if (!sp_die) {
764                         pr_warning("Failed to find probe point in any "
765                                    "functions.\n");
766                         return -ENOENT;
767                 }
768         }
769
770         /* Copy the name of probe point */
771         name = dwarf_diename(sp_die);
772         if (name) {
773                 if (dwarf_entrypc(sp_die, &eaddr) != 0) {
774                         pr_warning("Failed to get entry pc of %s\n",
775                                    dwarf_diename(sp_die));
776                         return -ENOENT;
777                 }
778                 tev->point.symbol = strdup(name);
779                 if (tev->point.symbol == NULL)
780                         return -ENOMEM;
781                 tev->point.offset = (unsigned long)(pf->addr - eaddr);
782         } else
783                 /* This function has no name. */
784                 tev->point.offset = (unsigned long)pf->addr;
785
786         pr_debug("Probe point found: %s+%lu\n", tev->point.symbol,
787                  tev->point.offset);
788
789         /* Get the frame base attribute/ops */
790         dwarf_attr(sp_die, DW_AT_frame_base, &fb_attr);
791         ret = dwarf_getlocation_addr(&fb_attr, pf->addr, &pf->fb_ops, &nops, 1);
792         if (ret <= 0 || nops == 0) {
793                 pf->fb_ops = NULL;
794 #if _ELFUTILS_PREREQ(0, 142)
795         } else if (nops == 1 && pf->fb_ops[0].atom == DW_OP_call_frame_cfa &&
796                    pf->cfi != NULL) {
797                 Dwarf_Frame *frame;
798                 if (dwarf_cfi_addrframe(pf->cfi, pf->addr, &frame) != 0 ||
799                     dwarf_frame_cfa(frame, &pf->fb_ops, &nops) != 0) {
800                         pr_warning("Failed to get CFA on 0x%jx\n",
801                                    (uintmax_t)pf->addr);
802                         return -ENOENT;
803                 }
804 #endif
805         }
806
807         /* Find each argument */
808         tev->nargs = pf->pev->nargs;
809         tev->args = zalloc(sizeof(struct probe_trace_arg) * tev->nargs);
810         if (tev->args == NULL)
811                 return -ENOMEM;
812         for (i = 0; i < pf->pev->nargs; i++) {
813                 pf->pvar = &pf->pev->args[i];
814                 pf->tvar = &tev->args[i];
815                 ret = find_variable(sp_die, pf);
816                 if (ret != 0)
817                         return ret;
818         }
819
820         /* *pf->fb_ops will be cached in libdw. Don't free it. */
821         pf->fb_ops = NULL;
822         return 0;
823 }
824
825 /* Find probe point from its line number */
826 static int find_probe_point_by_line(struct probe_finder *pf)
827 {
828         Dwarf_Lines *lines;
829         Dwarf_Line *line;
830         size_t nlines, i;
831         Dwarf_Addr addr;
832         int lineno;
833         int ret = 0;
834
835         if (dwarf_getsrclines(&pf->cu_die, &lines, &nlines) != 0) {
836                 pr_warning("No source lines found in this CU.\n");
837                 return -ENOENT;
838         }
839
840         for (i = 0; i < nlines && ret == 0; i++) {
841                 line = dwarf_onesrcline(lines, i);
842                 if (dwarf_lineno(line, &lineno) != 0 ||
843                     lineno != pf->lno)
844                         continue;
845
846                 /* TODO: Get fileno from line, but how? */
847                 if (strtailcmp(dwarf_linesrc(line, NULL, NULL), pf->fname) != 0)
848                         continue;
849
850                 if (dwarf_lineaddr(line, &addr) != 0) {
851                         pr_warning("Failed to get the address of the line.\n");
852                         return -ENOENT;
853                 }
854                 pr_debug("Probe line found: line[%d]:%d addr:0x%jx\n",
855                          (int)i, lineno, (uintmax_t)addr);
856                 pf->addr = addr;
857
858                 ret = convert_probe_point(NULL, pf);
859                 /* Continuing, because target line might be inlined. */
860         }
861         return ret;
862 }
863
864 /* Find lines which match lazy pattern */
865 static int find_lazy_match_lines(struct list_head *head,
866                                  const char *fname, const char *pat)
867 {
868         char *fbuf, *p1, *p2;
869         int fd, line, nlines = -1;
870         struct stat st;
871
872         fd = open(fname, O_RDONLY);
873         if (fd < 0) {
874                 pr_warning("Failed to open %s: %s\n", fname, strerror(-fd));
875                 return -errno;
876         }
877
878         if (fstat(fd, &st) < 0) {
879                 pr_warning("Failed to get the size of %s: %s\n",
880                            fname, strerror(errno));
881                 nlines = -errno;
882                 goto out_close;
883         }
884
885         nlines = -ENOMEM;
886         fbuf = malloc(st.st_size + 2);
887         if (fbuf == NULL)
888                 goto out_close;
889         if (read(fd, fbuf, st.st_size) < 0) {
890                 pr_warning("Failed to read %s: %s\n", fname, strerror(errno));
891                 nlines = -errno;
892                 goto out_free_fbuf;
893         }
894         fbuf[st.st_size] = '\n';        /* Dummy line */
895         fbuf[st.st_size + 1] = '\0';
896         p1 = fbuf;
897         line = 1;
898         nlines = 0;
899         while ((p2 = strchr(p1, '\n')) != NULL) {
900                 *p2 = '\0';
901                 if (strlazymatch(p1, pat)) {
902                         line_list__add_line(head, line);
903                         nlines++;
904                 }
905                 line++;
906                 p1 = p2 + 1;
907         }
908 out_free_fbuf:
909         free(fbuf);
910 out_close:
911         close(fd);
912         return nlines;
913 }
914
915 /* Find probe points from lazy pattern  */
916 static int find_probe_point_lazy(Dwarf_Die *sp_die, struct probe_finder *pf)
917 {
918         Dwarf_Lines *lines;
919         Dwarf_Line *line;
920         size_t nlines, i;
921         Dwarf_Addr addr;
922         Dwarf_Die die_mem;
923         int lineno;
924         int ret = 0;
925
926         if (list_empty(&pf->lcache)) {
927                 /* Matching lazy line pattern */
928                 ret = find_lazy_match_lines(&pf->lcache, pf->fname,
929                                             pf->pev->point.lazy_line);
930                 if (ret == 0) {
931                         pr_debug("No matched lines found in %s.\n", pf->fname);
932                         return 0;
933                 } else if (ret < 0)
934                         return ret;
935         }
936
937         if (dwarf_getsrclines(&pf->cu_die, &lines, &nlines) != 0) {
938                 pr_warning("No source lines found in this CU.\n");
939                 return -ENOENT;
940         }
941
942         for (i = 0; i < nlines && ret >= 0; i++) {
943                 line = dwarf_onesrcline(lines, i);
944
945                 if (dwarf_lineno(line, &lineno) != 0 ||
946                     !line_list__has_line(&pf->lcache, lineno))
947                         continue;
948
949                 /* TODO: Get fileno from line, but how? */
950                 if (strtailcmp(dwarf_linesrc(line, NULL, NULL), pf->fname) != 0)
951                         continue;
952
953                 if (dwarf_lineaddr(line, &addr) != 0) {
954                         pr_debug("Failed to get the address of line %d.\n",
955                                  lineno);
956                         continue;
957                 }
958                 if (sp_die) {
959                         /* Address filtering 1: does sp_die include addr? */
960                         if (!dwarf_haspc(sp_die, addr))
961                                 continue;
962                         /* Address filtering 2: No child include addr? */
963                         if (die_find_inlinefunc(sp_die, addr, &die_mem))
964                                 continue;
965                 }
966
967                 pr_debug("Probe line found: line[%d]:%d addr:0x%llx\n",
968                          (int)i, lineno, (unsigned long long)addr);
969                 pf->addr = addr;
970
971                 ret = convert_probe_point(sp_die, pf);
972                 /* Continuing, because target line might be inlined. */
973         }
974         /* TODO: deallocate lines, but how? */
975         return ret;
976 }
977
978 /* Callback parameter with return value */
979 struct dwarf_callback_param {
980         void *data;
981         int retval;
982 };
983
984 static int probe_point_inline_cb(Dwarf_Die *in_die, void *data)
985 {
986         struct dwarf_callback_param *param = data;
987         struct probe_finder *pf = param->data;
988         struct perf_probe_point *pp = &pf->pev->point;
989         Dwarf_Addr addr;
990
991         if (pp->lazy_line)
992                 param->retval = find_probe_point_lazy(in_die, pf);
993         else {
994                 /* Get probe address */
995                 if (dwarf_entrypc(in_die, &addr) != 0) {
996                         pr_warning("Failed to get entry pc of %s.\n",
997                                    dwarf_diename(in_die));
998                         param->retval = -ENOENT;
999                         return DWARF_CB_ABORT;
1000                 }
1001                 pf->addr = addr;
1002                 pf->addr += pp->offset;
1003                 pr_debug("found inline addr: 0x%jx\n",
1004                          (uintmax_t)pf->addr);
1005
1006                 param->retval = convert_probe_point(in_die, pf);
1007                 if (param->retval < 0)
1008                         return DWARF_CB_ABORT;
1009         }
1010
1011         return DWARF_CB_OK;
1012 }
1013
1014 /* Search function from function name */
1015 static int probe_point_search_cb(Dwarf_Die *sp_die, void *data)
1016 {
1017         struct dwarf_callback_param *param = data;
1018         struct probe_finder *pf = param->data;
1019         struct perf_probe_point *pp = &pf->pev->point;
1020
1021         /* Check tag and diename */
1022         if (dwarf_tag(sp_die) != DW_TAG_subprogram ||
1023             !die_compare_name(sp_die, pp->function))
1024                 return DWARF_CB_OK;
1025
1026         pf->fname = dwarf_decl_file(sp_die);
1027         if (pp->line) { /* Function relative line */
1028                 dwarf_decl_line(sp_die, &pf->lno);
1029                 pf->lno += pp->line;
1030                 param->retval = find_probe_point_by_line(pf);
1031         } else if (!dwarf_func_inline(sp_die)) {
1032                 /* Real function */
1033                 if (pp->lazy_line)
1034                         param->retval = find_probe_point_lazy(sp_die, pf);
1035                 else {
1036                         if (dwarf_entrypc(sp_die, &pf->addr) != 0) {
1037                                 pr_warning("Failed to get entry pc of %s.\n",
1038                                            dwarf_diename(sp_die));
1039                                 param->retval = -ENOENT;
1040                                 return DWARF_CB_ABORT;
1041                         }
1042                         pf->addr += pp->offset;
1043                         /* TODO: Check the address in this function */
1044                         param->retval = convert_probe_point(sp_die, pf);
1045                 }
1046         } else {
1047                 struct dwarf_callback_param _param = {.data = (void *)pf,
1048                                                       .retval = 0};
1049                 /* Inlined function: search instances */
1050                 dwarf_func_inline_instances(sp_die, probe_point_inline_cb,
1051                                             &_param);
1052                 param->retval = _param.retval;
1053         }
1054
1055         return DWARF_CB_ABORT; /* Exit; no same symbol in this CU. */
1056 }
1057
1058 static int find_probe_point_by_func(struct probe_finder *pf)
1059 {
1060         struct dwarf_callback_param _param = {.data = (void *)pf,
1061                                               .retval = 0};
1062         dwarf_getfuncs(&pf->cu_die, probe_point_search_cb, &_param, 0);
1063         return _param.retval;
1064 }
1065
1066 /* Find probe_trace_events specified by perf_probe_event from debuginfo */
1067 int find_probe_trace_events(int fd, struct perf_probe_event *pev,
1068                              struct probe_trace_event **tevs, int max_tevs)
1069 {
1070         struct probe_finder pf = {.pev = pev, .max_tevs = max_tevs};
1071         struct perf_probe_point *pp = &pev->point;
1072         Dwarf_Off off, noff;
1073         size_t cuhl;
1074         Dwarf_Die *diep;
1075         Dwarf *dbg;
1076         int ret = 0;
1077
1078         pf.tevs = zalloc(sizeof(struct probe_trace_event) * max_tevs);
1079         if (pf.tevs == NULL)
1080                 return -ENOMEM;
1081         *tevs = pf.tevs;
1082         pf.ntevs = 0;
1083
1084         dbg = dwarf_begin(fd, DWARF_C_READ);
1085         if (!dbg) {
1086                 pr_warning("No dwarf info found in the vmlinux - "
1087                         "please rebuild with CONFIG_DEBUG_INFO=y.\n");
1088                 free(pf.tevs);
1089                 *tevs = NULL;
1090                 return -EBADF;
1091         }
1092
1093 #if _ELFUTILS_PREREQ(0, 142)
1094         /* Get the call frame information from this dwarf */
1095         pf.cfi = dwarf_getcfi(dbg);
1096 #endif
1097
1098         off = 0;
1099         line_list__init(&pf.lcache);
1100         /* Loop on CUs (Compilation Unit) */
1101         while (!dwarf_nextcu(dbg, off, &noff, &cuhl, NULL, NULL, NULL) &&
1102                ret >= 0) {
1103                 /* Get the DIE(Debugging Information Entry) of this CU */
1104                 diep = dwarf_offdie(dbg, off + cuhl, &pf.cu_die);
1105                 if (!diep)
1106                         continue;
1107
1108                 /* Check if target file is included. */
1109                 if (pp->file)
1110                         pf.fname = cu_find_realpath(&pf.cu_die, pp->file);
1111                 else
1112                         pf.fname = NULL;
1113
1114                 if (!pp->file || pf.fname) {
1115                         if (pp->function)
1116                                 ret = find_probe_point_by_func(&pf);
1117                         else if (pp->lazy_line)
1118                                 ret = find_probe_point_lazy(NULL, &pf);
1119                         else {
1120                                 pf.lno = pp->line;
1121                                 ret = find_probe_point_by_line(&pf);
1122                         }
1123                 }
1124                 off = noff;
1125         }
1126         line_list__free(&pf.lcache);
1127         dwarf_end(dbg);
1128
1129         return (ret < 0) ? ret : pf.ntevs;
1130 }
1131
1132 /* Reverse search */
1133 int find_perf_probe_point(int fd, unsigned long addr,
1134                           struct perf_probe_point *ppt)
1135 {
1136         Dwarf_Die cudie, spdie, indie;
1137         Dwarf *dbg;
1138         Dwarf_Line *line;
1139         Dwarf_Addr laddr, eaddr;
1140         const char *tmp;
1141         int lineno, ret = 0;
1142         bool found = false;
1143
1144         dbg = dwarf_begin(fd, DWARF_C_READ);
1145         if (!dbg)
1146                 return -EBADF;
1147
1148         /* Find cu die */
1149         if (!dwarf_addrdie(dbg, (Dwarf_Addr)addr, &cudie)) {
1150                 ret = -EINVAL;
1151                 goto end;
1152         }
1153
1154         /* Find a corresponding line */
1155         line = dwarf_getsrc_die(&cudie, (Dwarf_Addr)addr);
1156         if (line) {
1157                 if (dwarf_lineaddr(line, &laddr) == 0 &&
1158                     (Dwarf_Addr)addr == laddr &&
1159                     dwarf_lineno(line, &lineno) == 0) {
1160                         tmp = dwarf_linesrc(line, NULL, NULL);
1161                         if (tmp) {
1162                                 ppt->line = lineno;
1163                                 ppt->file = strdup(tmp);
1164                                 if (ppt->file == NULL) {
1165                                         ret = -ENOMEM;
1166                                         goto end;
1167                                 }
1168                                 found = true;
1169                         }
1170                 }
1171         }
1172
1173         /* Find a corresponding function */
1174         if (die_find_real_subprogram(&cudie, (Dwarf_Addr)addr, &spdie)) {
1175                 tmp = dwarf_diename(&spdie);
1176                 if (!tmp || dwarf_entrypc(&spdie, &eaddr) != 0)
1177                         goto end;
1178
1179                 if (ppt->line) {
1180                         if (die_find_inlinefunc(&spdie, (Dwarf_Addr)addr,
1181                                                 &indie)) {
1182                                 /* addr in an inline function */
1183                                 tmp = dwarf_diename(&indie);
1184                                 if (!tmp)
1185                                         goto end;
1186                                 ret = dwarf_decl_line(&indie, &lineno);
1187                         } else {
1188                                 if (eaddr == addr) {    /* Function entry */
1189                                         lineno = ppt->line;
1190                                         ret = 0;
1191                                 } else
1192                                         ret = dwarf_decl_line(&spdie, &lineno);
1193                         }
1194                         if (ret == 0) {
1195                                 /* Make a relative line number */
1196                                 ppt->line -= lineno;
1197                                 goto found;
1198                         }
1199                 }
1200                 /* We don't have a line number, let's use offset */
1201                 ppt->offset = addr - (unsigned long)eaddr;
1202 found:
1203                 ppt->function = strdup(tmp);
1204                 if (ppt->function == NULL) {
1205                         ret = -ENOMEM;
1206                         goto end;
1207                 }
1208                 found = true;
1209         }
1210
1211 end:
1212         dwarf_end(dbg);
1213         if (ret >= 0)
1214                 ret = found ? 1 : 0;
1215         return ret;
1216 }
1217
1218 /* Add a line and store the src path */
1219 static int line_range_add_line(const char *src, unsigned int lineno,
1220                                struct line_range *lr)
1221 {
1222         /* Copy source path */
1223         if (!lr->path) {
1224                 lr->path = strdup(src);
1225                 if (lr->path == NULL)
1226                         return -ENOMEM;
1227         }
1228         return line_list__add_line(&lr->line_list, lineno);
1229 }
1230
1231 /* Search function declaration lines */
1232 static int line_range_funcdecl_cb(Dwarf_Die *sp_die, void *data)
1233 {
1234         struct dwarf_callback_param *param = data;
1235         struct line_finder *lf = param->data;
1236         const char *src;
1237         int lineno;
1238
1239         src = dwarf_decl_file(sp_die);
1240         if (src && strtailcmp(src, lf->fname) != 0)
1241                 return DWARF_CB_OK;
1242
1243         if (dwarf_decl_line(sp_die, &lineno) != 0 ||
1244             (lf->lno_s > lineno || lf->lno_e < lineno))
1245                 return DWARF_CB_OK;
1246
1247         param->retval = line_range_add_line(src, lineno, lf->lr);
1248         if (param->retval < 0)
1249                 return DWARF_CB_ABORT;
1250         return DWARF_CB_OK;
1251 }
1252
1253 static int find_line_range_func_decl_lines(struct line_finder *lf)
1254 {
1255         struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
1256         dwarf_getfuncs(&lf->cu_die, line_range_funcdecl_cb, &param, 0);
1257         return param.retval;
1258 }
1259
1260 /* Find line range from its line number */
1261 static int find_line_range_by_line(Dwarf_Die *sp_die, struct line_finder *lf)
1262 {
1263         Dwarf_Lines *lines;
1264         Dwarf_Line *line;
1265         size_t nlines, i;
1266         Dwarf_Addr addr;
1267         int lineno, ret = 0;
1268         const char *src;
1269         Dwarf_Die die_mem;
1270
1271         line_list__init(&lf->lr->line_list);
1272         if (dwarf_getsrclines(&lf->cu_die, &lines, &nlines) != 0) {
1273                 pr_warning("No source lines found in this CU.\n");
1274                 return -ENOENT;
1275         }
1276
1277         /* Search probable lines on lines list */
1278         for (i = 0; i < nlines; i++) {
1279                 line = dwarf_onesrcline(lines, i);
1280                 if (dwarf_lineno(line, &lineno) != 0 ||
1281                     (lf->lno_s > lineno || lf->lno_e < lineno))
1282                         continue;
1283
1284                 if (sp_die) {
1285                         /* Address filtering 1: does sp_die include addr? */
1286                         if (dwarf_lineaddr(line, &addr) != 0 ||
1287                             !dwarf_haspc(sp_die, addr))
1288                                 continue;
1289
1290                         /* Address filtering 2: No child include addr? */
1291                         if (die_find_inlinefunc(sp_die, addr, &die_mem))
1292                                 continue;
1293                 }
1294
1295                 /* TODO: Get fileno from line, but how? */
1296                 src = dwarf_linesrc(line, NULL, NULL);
1297                 if (strtailcmp(src, lf->fname) != 0)
1298                         continue;
1299
1300                 ret = line_range_add_line(src, lineno, lf->lr);
1301                 if (ret < 0)
1302                         return ret;
1303         }
1304
1305         /*
1306          * Dwarf lines doesn't include function declarations. We have to
1307          * check functions list or given function.
1308          */
1309         if (sp_die) {
1310                 src = dwarf_decl_file(sp_die);
1311                 if (src && dwarf_decl_line(sp_die, &lineno) == 0 &&
1312                     (lf->lno_s <= lineno && lf->lno_e >= lineno))
1313                         ret = line_range_add_line(src, lineno, lf->lr);
1314         } else
1315                 ret = find_line_range_func_decl_lines(lf);
1316
1317         /* Update status */
1318         if (ret >= 0)
1319                 if (!list_empty(&lf->lr->line_list))
1320                         ret = lf->found = 1;
1321                 else
1322                         ret = 0;        /* Lines are not found */
1323         else {
1324                 free(lf->lr->path);
1325                 lf->lr->path = NULL;
1326         }
1327         return ret;
1328 }
1329
1330 static int line_range_inline_cb(Dwarf_Die *in_die, void *data)
1331 {
1332         struct dwarf_callback_param *param = data;
1333
1334         param->retval = find_line_range_by_line(in_die, param->data);
1335         return DWARF_CB_ABORT;  /* No need to find other instances */
1336 }
1337
1338 /* Search function from function name */
1339 static int line_range_search_cb(Dwarf_Die *sp_die, void *data)
1340 {
1341         struct dwarf_callback_param *param = data;
1342         struct line_finder *lf = param->data;
1343         struct line_range *lr = lf->lr;
1344
1345         if (dwarf_tag(sp_die) == DW_TAG_subprogram &&
1346             die_compare_name(sp_die, lr->function)) {
1347                 lf->fname = dwarf_decl_file(sp_die);
1348                 dwarf_decl_line(sp_die, &lr->offset);
1349                 pr_debug("fname: %s, lineno:%d\n", lf->fname, lr->offset);
1350                 lf->lno_s = lr->offset + lr->start;
1351                 if (lf->lno_s < 0)      /* Overflow */
1352                         lf->lno_s = INT_MAX;
1353                 lf->lno_e = lr->offset + lr->end;
1354                 if (lf->lno_e < 0)      /* Overflow */
1355                         lf->lno_e = INT_MAX;
1356                 pr_debug("New line range: %d to %d\n", lf->lno_s, lf->lno_e);
1357                 lr->start = lf->lno_s;
1358                 lr->end = lf->lno_e;
1359                 if (dwarf_func_inline(sp_die)) {
1360                         struct dwarf_callback_param _param;
1361                         _param.data = (void *)lf;
1362                         _param.retval = 0;
1363                         dwarf_func_inline_instances(sp_die,
1364                                                     line_range_inline_cb,
1365                                                     &_param);
1366                         param->retval = _param.retval;
1367                 } else
1368                         param->retval = find_line_range_by_line(sp_die, lf);
1369                 return DWARF_CB_ABORT;
1370         }
1371         return DWARF_CB_OK;
1372 }
1373
1374 static int find_line_range_by_func(struct line_finder *lf)
1375 {
1376         struct dwarf_callback_param param = {.data = (void *)lf, .retval = 0};
1377         dwarf_getfuncs(&lf->cu_die, line_range_search_cb, &param, 0);
1378         return param.retval;
1379 }
1380
1381 int find_line_range(int fd, struct line_range *lr)
1382 {
1383         struct line_finder lf = {.lr = lr, .found = 0};
1384         int ret = 0;
1385         Dwarf_Off off = 0, noff;
1386         size_t cuhl;
1387         Dwarf_Die *diep;
1388         Dwarf *dbg;
1389         const char *comp_dir;
1390
1391         dbg = dwarf_begin(fd, DWARF_C_READ);
1392         if (!dbg) {
1393                 pr_warning("No dwarf info found in the vmlinux - "
1394                         "please rebuild with CONFIG_DEBUG_INFO=y.\n");
1395                 return -EBADF;
1396         }
1397
1398         /* Loop on CUs (Compilation Unit) */
1399         while (!lf.found && ret >= 0) {
1400                 if (dwarf_nextcu(dbg, off, &noff, &cuhl, NULL, NULL, NULL) != 0)
1401                         break;
1402
1403                 /* Get the DIE(Debugging Information Entry) of this CU */
1404                 diep = dwarf_offdie(dbg, off + cuhl, &lf.cu_die);
1405                 if (!diep)
1406                         continue;
1407
1408                 /* Check if target file is included. */
1409                 if (lr->file)
1410                         lf.fname = cu_find_realpath(&lf.cu_die, lr->file);
1411                 else
1412                         lf.fname = 0;
1413
1414                 if (!lr->file || lf.fname) {
1415                         if (lr->function)
1416                                 ret = find_line_range_by_func(&lf);
1417                         else {
1418                                 lf.lno_s = lr->start;
1419                                 lf.lno_e = lr->end;
1420                                 ret = find_line_range_by_line(NULL, &lf);
1421                         }
1422                 }
1423                 off = noff;
1424         }
1425
1426         /* Store comp_dir */
1427         if (lf.found) {
1428                 comp_dir = cu_get_comp_dir(&lf.cu_die);
1429                 if (comp_dir) {
1430                         lr->comp_dir = strdup(comp_dir);
1431                         if (!lr->comp_dir)
1432                                 ret = -ENOMEM;
1433                 }
1434         }
1435
1436         pr_debug("path: %s\n", lr->path);
1437         dwarf_end(dbg);
1438
1439         return (ret < 0) ? ret : lf.found;
1440 }
1441