Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * bpf-loader.c
4 *
5 * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
6 * Copyright (C) 2015 Huawei Inc.
7 */
8
9#include <linux/bpf.h>
10#include <bpf/libbpf.h>
11#include <bpf/bpf.h>
12#include <linux/filter.h>
13#include <linux/err.h>
14#include <linux/kernel.h>
15#include <linux/string.h>
16#include <linux/zalloc.h>
17#include <errno.h>
18#include <stdlib.h>
19#include "debug.h"
20#include "evlist.h"
21#include "bpf-loader.h"
22#include "bpf-prologue.h"
23#include "probe-event.h"
24#include "probe-finder.h" // for MAX_PROBES
25#include "parse-events.h"
26#include "strfilter.h"
27#include "util.h"
28#include "llvm-utils.h"
29#include "c++/clang-c.h"
30#include "util/hashmap.h"
31#include "asm/bug.h"
32
33#include <internal/xyarray.h>
34
35/* temporarily disable libbpf deprecation warnings */
36#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
37
38static int libbpf_perf_print(enum libbpf_print_level level __attribute__((unused)),
39 const char *fmt, va_list args)
40{
41 return veprintf(1, verbose, pr_fmt(fmt), args);
42}
43
44struct bpf_prog_priv {
45 bool is_tp;
46 char *sys_name;
47 char *evt_name;
48 struct perf_probe_event pev;
49 bool need_prologue;
50 struct bpf_insn *insns_buf;
51 int nr_types;
52 int *type_mapping;
53 int *prologue_fds;
54};
55
56struct bpf_perf_object {
57 struct list_head list;
58 struct bpf_object *obj;
59};
60
61struct bpf_preproc_result {
62 struct bpf_insn *new_insn_ptr;
63 int new_insn_cnt;
64};
65
66static LIST_HEAD(bpf_objects_list);
67static struct hashmap *bpf_program_hash;
68static struct hashmap *bpf_map_hash;
69
70static struct bpf_perf_object *
71bpf_perf_object__next(struct bpf_perf_object *prev)
72{
73 if (!prev) {
74 if (list_empty(&bpf_objects_list))
75 return NULL;
76
77 return list_first_entry(&bpf_objects_list, struct bpf_perf_object, list);
78 }
79 if (list_is_last(&prev->list, &bpf_objects_list))
80 return NULL;
81
82 return list_next_entry(prev, list);
83}
84
85#define bpf_perf_object__for_each(perf_obj, tmp) \
86 for ((perf_obj) = bpf_perf_object__next(NULL), \
87 (tmp) = bpf_perf_object__next(perf_obj); \
88 (perf_obj) != NULL; \
89 (perf_obj) = (tmp), (tmp) = bpf_perf_object__next(tmp))
90
91static bool libbpf_initialized;
92static int libbpf_sec_handler;
93
94static int bpf_perf_object__add(struct bpf_object *obj)
95{
96 struct bpf_perf_object *perf_obj = zalloc(sizeof(*perf_obj));
97
98 if (perf_obj) {
99 INIT_LIST_HEAD(&perf_obj->list);
100 perf_obj->obj = obj;
101 list_add_tail(&perf_obj->list, &bpf_objects_list);
102 }
103 return perf_obj ? 0 : -ENOMEM;
104}
105
106static void *program_priv(const struct bpf_program *prog)
107{
108 void *priv;
109
110 if (IS_ERR_OR_NULL(bpf_program_hash))
111 return NULL;
112 if (!hashmap__find(bpf_program_hash, prog, &priv))
113 return NULL;
114 return priv;
115}
116
117static struct bpf_insn prologue_init_insn[] = {
118 BPF_MOV64_IMM(BPF_REG_2, 0),
119 BPF_MOV64_IMM(BPF_REG_3, 0),
120 BPF_MOV64_IMM(BPF_REG_4, 0),
121 BPF_MOV64_IMM(BPF_REG_5, 0),
122};
123
124static int libbpf_prog_prepare_load_fn(struct bpf_program *prog,
125 struct bpf_prog_load_opts *opts __maybe_unused,
126 long cookie __maybe_unused)
127{
128 size_t init_size_cnt = ARRAY_SIZE(prologue_init_insn);
129 size_t orig_insn_cnt, insn_cnt, init_size, orig_size;
130 struct bpf_prog_priv *priv = program_priv(prog);
131 const struct bpf_insn *orig_insn;
132 struct bpf_insn *insn;
133
134 if (IS_ERR_OR_NULL(priv)) {
135 pr_debug("bpf: failed to get private field\n");
136 return -BPF_LOADER_ERRNO__INTERNAL;
137 }
138
139 if (!priv->need_prologue)
140 return 0;
141
142 /* prepend initialization code to program instructions */
143 orig_insn = bpf_program__insns(prog);
144 orig_insn_cnt = bpf_program__insn_cnt(prog);
145 init_size = init_size_cnt * sizeof(*insn);
146 orig_size = orig_insn_cnt * sizeof(*insn);
147
148 insn_cnt = orig_insn_cnt + init_size_cnt;
149 insn = malloc(insn_cnt * sizeof(*insn));
150 if (!insn)
151 return -ENOMEM;
152
153 memcpy(insn, prologue_init_insn, init_size);
154 memcpy((char *) insn + init_size, orig_insn, orig_size);
155 bpf_program__set_insns(prog, insn, insn_cnt);
156 return 0;
157}
158
159static int libbpf_init(void)
160{
161 LIBBPF_OPTS(libbpf_prog_handler_opts, handler_opts,
162 .prog_prepare_load_fn = libbpf_prog_prepare_load_fn,
163 );
164
165 if (libbpf_initialized)
166 return 0;
167
168 libbpf_set_print(libbpf_perf_print);
169 libbpf_sec_handler = libbpf_register_prog_handler(NULL, BPF_PROG_TYPE_KPROBE,
170 0, &handler_opts);
171 if (libbpf_sec_handler < 0) {
172 pr_debug("bpf: failed to register libbpf section handler: %d\n",
173 libbpf_sec_handler);
174 return -BPF_LOADER_ERRNO__INTERNAL;
175 }
176 libbpf_initialized = true;
177 return 0;
178}
179
180struct bpf_object *
181bpf__prepare_load_buffer(void *obj_buf, size_t obj_buf_sz, const char *name)
182{
183 LIBBPF_OPTS(bpf_object_open_opts, opts, .object_name = name);
184 struct bpf_object *obj;
185 int err;
186
187 err = libbpf_init();
188 if (err)
189 return ERR_PTR(err);
190
191 obj = bpf_object__open_mem(obj_buf, obj_buf_sz, &opts);
192 if (IS_ERR_OR_NULL(obj)) {
193 pr_debug("bpf: failed to load buffer\n");
194 return ERR_PTR(-EINVAL);
195 }
196
197 if (bpf_perf_object__add(obj)) {
198 bpf_object__close(obj);
199 return ERR_PTR(-ENOMEM);
200 }
201
202 return obj;
203}
204
205static void bpf_perf_object__close(struct bpf_perf_object *perf_obj)
206{
207 list_del(&perf_obj->list);
208 bpf_object__close(perf_obj->obj);
209 free(perf_obj);
210}
211
212struct bpf_object *bpf__prepare_load(const char *filename, bool source)
213{
214 LIBBPF_OPTS(bpf_object_open_opts, opts, .object_name = filename);
215 struct bpf_object *obj;
216 int err;
217
218 err = libbpf_init();
219 if (err)
220 return ERR_PTR(err);
221
222 if (source) {
223 void *obj_buf;
224 size_t obj_buf_sz;
225
226 perf_clang__init();
227 err = perf_clang__compile_bpf(filename, &obj_buf, &obj_buf_sz);
228 perf_clang__cleanup();
229 if (err) {
230 pr_debug("bpf: builtin compilation failed: %d, try external compiler\n", err);
231 err = llvm__compile_bpf(filename, &obj_buf, &obj_buf_sz);
232 if (err)
233 return ERR_PTR(-BPF_LOADER_ERRNO__COMPILE);
234 } else
235 pr_debug("bpf: successful builtin compilation\n");
236 obj = bpf_object__open_mem(obj_buf, obj_buf_sz, &opts);
237
238 if (!IS_ERR_OR_NULL(obj) && llvm_param.dump_obj)
239 llvm__dump_obj(filename, obj_buf, obj_buf_sz);
240
241 free(obj_buf);
242 } else {
243 obj = bpf_object__open(filename);
244 }
245
246 if (IS_ERR_OR_NULL(obj)) {
247 pr_debug("bpf: failed to load %s\n", filename);
248 return obj;
249 }
250
251 if (bpf_perf_object__add(obj)) {
252 bpf_object__close(obj);
253 return ERR_PTR(-BPF_LOADER_ERRNO__COMPILE);
254 }
255
256 return obj;
257}
258
259static void close_prologue_programs(struct bpf_prog_priv *priv)
260{
261 struct perf_probe_event *pev;
262 int i, fd;
263
264 if (!priv->need_prologue)
265 return;
266 pev = &priv->pev;
267 for (i = 0; i < pev->ntevs; i++) {
268 fd = priv->prologue_fds[i];
269 if (fd != -1)
270 close(fd);
271 }
272}
273
274static void
275clear_prog_priv(const struct bpf_program *prog __maybe_unused,
276 void *_priv)
277{
278 struct bpf_prog_priv *priv = _priv;
279
280 close_prologue_programs(priv);
281 cleanup_perf_probe_events(&priv->pev, 1);
282 zfree(&priv->insns_buf);
283 zfree(&priv->prologue_fds);
284 zfree(&priv->type_mapping);
285 zfree(&priv->sys_name);
286 zfree(&priv->evt_name);
287 free(priv);
288}
289
290static void bpf_program_hash_free(void)
291{
292 struct hashmap_entry *cur;
293 size_t bkt;
294
295 if (IS_ERR_OR_NULL(bpf_program_hash))
296 return;
297
298 hashmap__for_each_entry(bpf_program_hash, cur, bkt)
299 clear_prog_priv(cur->pkey, cur->pvalue);
300
301 hashmap__free(bpf_program_hash);
302 bpf_program_hash = NULL;
303}
304
305static void bpf_map_hash_free(void);
306
307void bpf__clear(void)
308{
309 struct bpf_perf_object *perf_obj, *tmp;
310
311 bpf_perf_object__for_each(perf_obj, tmp) {
312 bpf__unprobe(perf_obj->obj);
313 bpf_perf_object__close(perf_obj);
314 }
315
316 bpf_program_hash_free();
317 bpf_map_hash_free();
318}
319
320static size_t ptr_hash(const long __key, void *ctx __maybe_unused)
321{
322 return __key;
323}
324
325static bool ptr_equal(long key1, long key2, void *ctx __maybe_unused)
326{
327 return key1 == key2;
328}
329
330static int program_set_priv(struct bpf_program *prog, void *priv)
331{
332 void *old_priv;
333
334 /*
335 * Should not happen, we warn about it in the
336 * caller function - config_bpf_program
337 */
338 if (IS_ERR(bpf_program_hash))
339 return PTR_ERR(bpf_program_hash);
340
341 if (!bpf_program_hash) {
342 bpf_program_hash = hashmap__new(ptr_hash, ptr_equal, NULL);
343 if (IS_ERR(bpf_program_hash))
344 return PTR_ERR(bpf_program_hash);
345 }
346
347 old_priv = program_priv(prog);
348 if (old_priv) {
349 clear_prog_priv(prog, old_priv);
350 return hashmap__set(bpf_program_hash, prog, priv, NULL, NULL);
351 }
352 return hashmap__add(bpf_program_hash, prog, priv);
353}
354
355static int
356prog_config__exec(const char *value, struct perf_probe_event *pev)
357{
358 pev->uprobes = true;
359 pev->target = strdup(value);
360 if (!pev->target)
361 return -ENOMEM;
362 return 0;
363}
364
365static int
366prog_config__module(const char *value, struct perf_probe_event *pev)
367{
368 pev->uprobes = false;
369 pev->target = strdup(value);
370 if (!pev->target)
371 return -ENOMEM;
372 return 0;
373}
374
375static int
376prog_config__bool(const char *value, bool *pbool, bool invert)
377{
378 int err;
379 bool bool_value;
380
381 if (!pbool)
382 return -EINVAL;
383
384 err = strtobool(value, &bool_value);
385 if (err)
386 return err;
387
388 *pbool = invert ? !bool_value : bool_value;
389 return 0;
390}
391
392static int
393prog_config__inlines(const char *value,
394 struct perf_probe_event *pev __maybe_unused)
395{
396 return prog_config__bool(value, &probe_conf.no_inlines, true);
397}
398
399static int
400prog_config__force(const char *value,
401 struct perf_probe_event *pev __maybe_unused)
402{
403 return prog_config__bool(value, &probe_conf.force_add, false);
404}
405
406static struct {
407 const char *key;
408 const char *usage;
409 const char *desc;
410 int (*func)(const char *, struct perf_probe_event *);
411} bpf_prog_config_terms[] = {
412 {
413 .key = "exec",
414 .usage = "exec=<full path of file>",
415 .desc = "Set uprobe target",
416 .func = prog_config__exec,
417 },
418 {
419 .key = "module",
420 .usage = "module=<module name> ",
421 .desc = "Set kprobe module",
422 .func = prog_config__module,
423 },
424 {
425 .key = "inlines",
426 .usage = "inlines=[yes|no] ",
427 .desc = "Probe at inline symbol",
428 .func = prog_config__inlines,
429 },
430 {
431 .key = "force",
432 .usage = "force=[yes|no] ",
433 .desc = "Forcibly add events with existing name",
434 .func = prog_config__force,
435 },
436};
437
438static int
439do_prog_config(const char *key, const char *value,
440 struct perf_probe_event *pev)
441{
442 unsigned int i;
443
444 pr_debug("config bpf program: %s=%s\n", key, value);
445 for (i = 0; i < ARRAY_SIZE(bpf_prog_config_terms); i++)
446 if (strcmp(key, bpf_prog_config_terms[i].key) == 0)
447 return bpf_prog_config_terms[i].func(value, pev);
448
449 pr_debug("BPF: ERROR: invalid program config option: %s=%s\n",
450 key, value);
451
452 pr_debug("\nHint: Valid options are:\n");
453 for (i = 0; i < ARRAY_SIZE(bpf_prog_config_terms); i++)
454 pr_debug("\t%s:\t%s\n", bpf_prog_config_terms[i].usage,
455 bpf_prog_config_terms[i].desc);
456 pr_debug("\n");
457
458 return -BPF_LOADER_ERRNO__PROGCONF_TERM;
459}
460
461static const char *
462parse_prog_config_kvpair(const char *config_str, struct perf_probe_event *pev)
463{
464 char *text = strdup(config_str);
465 char *sep, *line;
466 const char *main_str = NULL;
467 int err = 0;
468
469 if (!text) {
470 pr_debug("Not enough memory: dup config_str failed\n");
471 return ERR_PTR(-ENOMEM);
472 }
473
474 line = text;
475 while ((sep = strchr(line, ';'))) {
476 char *equ;
477
478 *sep = '\0';
479 equ = strchr(line, '=');
480 if (!equ) {
481 pr_warning("WARNING: invalid config in BPF object: %s\n",
482 line);
483 pr_warning("\tShould be 'key=value'.\n");
484 goto nextline;
485 }
486 *equ = '\0';
487
488 err = do_prog_config(line, equ + 1, pev);
489 if (err)
490 break;
491nextline:
492 line = sep + 1;
493 }
494
495 if (!err)
496 main_str = config_str + (line - text);
497 free(text);
498
499 return err ? ERR_PTR(err) : main_str;
500}
501
502static int
503parse_prog_config(const char *config_str, const char **p_main_str,
504 bool *is_tp, struct perf_probe_event *pev)
505{
506 int err;
507 const char *main_str = parse_prog_config_kvpair(config_str, pev);
508
509 if (IS_ERR(main_str))
510 return PTR_ERR(main_str);
511
512 *p_main_str = main_str;
513 if (!strchr(main_str, '=')) {
514 /* Is a tracepoint event? */
515 const char *s = strchr(main_str, ':');
516
517 if (!s) {
518 pr_debug("bpf: '%s' is not a valid tracepoint\n",
519 config_str);
520 return -BPF_LOADER_ERRNO__CONFIG;
521 }
522
523 *is_tp = true;
524 return 0;
525 }
526
527 *is_tp = false;
528 err = parse_perf_probe_command(main_str, pev);
529 if (err < 0) {
530 pr_debug("bpf: '%s' is not a valid config string\n",
531 config_str);
532 /* parse failed, don't need clear pev. */
533 return -BPF_LOADER_ERRNO__CONFIG;
534 }
535 return 0;
536}
537
538static int
539config_bpf_program(struct bpf_program *prog)
540{
541 struct perf_probe_event *pev = NULL;
542 struct bpf_prog_priv *priv = NULL;
543 const char *config_str, *main_str;
544 bool is_tp = false;
545 int err;
546
547 /* Initialize per-program probing setting */
548 probe_conf.no_inlines = false;
549 probe_conf.force_add = false;
550
551 priv = calloc(sizeof(*priv), 1);
552 if (!priv) {
553 pr_debug("bpf: failed to alloc priv\n");
554 return -ENOMEM;
555 }
556 pev = &priv->pev;
557
558 config_str = bpf_program__section_name(prog);
559 pr_debug("bpf: config program '%s'\n", config_str);
560 err = parse_prog_config(config_str, &main_str, &is_tp, pev);
561 if (err)
562 goto errout;
563
564 if (is_tp) {
565 char *s = strchr(main_str, ':');
566
567 priv->is_tp = true;
568 priv->sys_name = strndup(main_str, s - main_str);
569 priv->evt_name = strdup(s + 1);
570 goto set_priv;
571 }
572
573 if (pev->group && strcmp(pev->group, PERF_BPF_PROBE_GROUP)) {
574 pr_debug("bpf: '%s': group for event is set and not '%s'.\n",
575 config_str, PERF_BPF_PROBE_GROUP);
576 err = -BPF_LOADER_ERRNO__GROUP;
577 goto errout;
578 } else if (!pev->group)
579 pev->group = strdup(PERF_BPF_PROBE_GROUP);
580
581 if (!pev->group) {
582 pr_debug("bpf: strdup failed\n");
583 err = -ENOMEM;
584 goto errout;
585 }
586
587 if (!pev->event) {
588 pr_debug("bpf: '%s': event name is missing. Section name should be 'key=value'\n",
589 config_str);
590 err = -BPF_LOADER_ERRNO__EVENTNAME;
591 goto errout;
592 }
593 pr_debug("bpf: config '%s' is ok\n", config_str);
594
595set_priv:
596 err = program_set_priv(prog, priv);
597 if (err) {
598 pr_debug("Failed to set priv for program '%s'\n", config_str);
599 goto errout;
600 }
601
602 return 0;
603
604errout:
605 if (pev)
606 clear_perf_probe_event(pev);
607 free(priv);
608 return err;
609}
610
611static int bpf__prepare_probe(void)
612{
613 static int err = 0;
614 static bool initialized = false;
615
616 /*
617 * Make err static, so if init failed the first, bpf__prepare_probe()
618 * fails each time without calling init_probe_symbol_maps multiple
619 * times.
620 */
621 if (initialized)
622 return err;
623
624 initialized = true;
625 err = init_probe_symbol_maps(false);
626 if (err < 0)
627 pr_debug("Failed to init_probe_symbol_maps\n");
628 probe_conf.max_probes = MAX_PROBES;
629 return err;
630}
631
632static int
633preproc_gen_prologue(struct bpf_program *prog, int n,
634 const struct bpf_insn *orig_insns, int orig_insns_cnt,
635 struct bpf_preproc_result *res)
636{
637 struct bpf_prog_priv *priv = program_priv(prog);
638 struct probe_trace_event *tev;
639 struct perf_probe_event *pev;
640 struct bpf_insn *buf;
641 size_t prologue_cnt = 0;
642 int i, err;
643
644 if (IS_ERR_OR_NULL(priv) || priv->is_tp)
645 goto errout;
646
647 pev = &priv->pev;
648
649 if (n < 0 || n >= priv->nr_types)
650 goto errout;
651
652 /* Find a tev belongs to that type */
653 for (i = 0; i < pev->ntevs; i++) {
654 if (priv->type_mapping[i] == n)
655 break;
656 }
657
658 if (i >= pev->ntevs) {
659 pr_debug("Internal error: prologue type %d not found\n", n);
660 return -BPF_LOADER_ERRNO__PROLOGUE;
661 }
662
663 tev = &pev->tevs[i];
664
665 buf = priv->insns_buf;
666 err = bpf__gen_prologue(tev->args, tev->nargs,
667 buf, &prologue_cnt,
668 BPF_MAXINSNS - orig_insns_cnt);
669 if (err) {
670 const char *title;
671
672 title = bpf_program__section_name(prog);
673 pr_debug("Failed to generate prologue for program %s\n",
674 title);
675 return err;
676 }
677
678 memcpy(&buf[prologue_cnt], orig_insns,
679 sizeof(struct bpf_insn) * orig_insns_cnt);
680
681 res->new_insn_ptr = buf;
682 res->new_insn_cnt = prologue_cnt + orig_insns_cnt;
683 return 0;
684
685errout:
686 pr_debug("Internal error in preproc_gen_prologue\n");
687 return -BPF_LOADER_ERRNO__PROLOGUE;
688}
689
690/*
691 * compare_tev_args is reflexive, transitive and antisymmetric.
692 * I can proof it but this margin is too narrow to contain.
693 */
694static int compare_tev_args(const void *ptev1, const void *ptev2)
695{
696 int i, ret;
697 const struct probe_trace_event *tev1 =
698 *(const struct probe_trace_event **)ptev1;
699 const struct probe_trace_event *tev2 =
700 *(const struct probe_trace_event **)ptev2;
701
702 ret = tev2->nargs - tev1->nargs;
703 if (ret)
704 return ret;
705
706 for (i = 0; i < tev1->nargs; i++) {
707 struct probe_trace_arg *arg1, *arg2;
708 struct probe_trace_arg_ref *ref1, *ref2;
709
710 arg1 = &tev1->args[i];
711 arg2 = &tev2->args[i];
712
713 ret = strcmp(arg1->value, arg2->value);
714 if (ret)
715 return ret;
716
717 ref1 = arg1->ref;
718 ref2 = arg2->ref;
719
720 while (ref1 && ref2) {
721 ret = ref2->offset - ref1->offset;
722 if (ret)
723 return ret;
724
725 ref1 = ref1->next;
726 ref2 = ref2->next;
727 }
728
729 if (ref1 || ref2)
730 return ref2 ? 1 : -1;
731 }
732
733 return 0;
734}
735
736/*
737 * Assign a type number to each tevs in a pev.
738 * mapping is an array with same slots as tevs in that pev.
739 * nr_types will be set to number of types.
740 */
741static int map_prologue(struct perf_probe_event *pev, int *mapping,
742 int *nr_types)
743{
744 int i, type = 0;
745 struct probe_trace_event **ptevs;
746
747 size_t array_sz = sizeof(*ptevs) * pev->ntevs;
748
749 ptevs = malloc(array_sz);
750 if (!ptevs) {
751 pr_debug("Not enough memory: alloc ptevs failed\n");
752 return -ENOMEM;
753 }
754
755 pr_debug("In map_prologue, ntevs=%d\n", pev->ntevs);
756 for (i = 0; i < pev->ntevs; i++)
757 ptevs[i] = &pev->tevs[i];
758
759 qsort(ptevs, pev->ntevs, sizeof(*ptevs),
760 compare_tev_args);
761
762 for (i = 0; i < pev->ntevs; i++) {
763 int n;
764
765 n = ptevs[i] - pev->tevs;
766 if (i == 0) {
767 mapping[n] = type;
768 pr_debug("mapping[%d]=%d\n", n, type);
769 continue;
770 }
771
772 if (compare_tev_args(ptevs + i, ptevs + i - 1) == 0)
773 mapping[n] = type;
774 else
775 mapping[n] = ++type;
776
777 pr_debug("mapping[%d]=%d\n", n, mapping[n]);
778 }
779 free(ptevs);
780 *nr_types = type + 1;
781
782 return 0;
783}
784
785static int hook_load_preprocessor(struct bpf_program *prog)
786{
787 struct bpf_prog_priv *priv = program_priv(prog);
788 struct perf_probe_event *pev;
789 bool need_prologue = false;
790 int i;
791
792 if (IS_ERR_OR_NULL(priv)) {
793 pr_debug("Internal error when hook preprocessor\n");
794 return -BPF_LOADER_ERRNO__INTERNAL;
795 }
796
797 if (priv->is_tp) {
798 priv->need_prologue = false;
799 return 0;
800 }
801
802 pev = &priv->pev;
803 for (i = 0; i < pev->ntevs; i++) {
804 struct probe_trace_event *tev = &pev->tevs[i];
805
806 if (tev->nargs > 0) {
807 need_prologue = true;
808 break;
809 }
810 }
811
812 /*
813 * Since all tevs don't have argument, we don't need generate
814 * prologue.
815 */
816 if (!need_prologue) {
817 priv->need_prologue = false;
818 return 0;
819 }
820
821 priv->need_prologue = true;
822 priv->insns_buf = malloc(sizeof(struct bpf_insn) * BPF_MAXINSNS);
823 if (!priv->insns_buf) {
824 pr_debug("Not enough memory: alloc insns_buf failed\n");
825 return -ENOMEM;
826 }
827
828 priv->prologue_fds = malloc(sizeof(int) * pev->ntevs);
829 if (!priv->prologue_fds) {
830 pr_debug("Not enough memory: alloc prologue fds failed\n");
831 return -ENOMEM;
832 }
833 memset(priv->prologue_fds, -1, sizeof(int) * pev->ntevs);
834
835 priv->type_mapping = malloc(sizeof(int) * pev->ntevs);
836 if (!priv->type_mapping) {
837 pr_debug("Not enough memory: alloc type_mapping failed\n");
838 return -ENOMEM;
839 }
840 memset(priv->type_mapping, -1,
841 sizeof(int) * pev->ntevs);
842
843 return map_prologue(pev, priv->type_mapping, &priv->nr_types);
844}
845
846int bpf__probe(struct bpf_object *obj)
847{
848 int err = 0;
849 struct bpf_program *prog;
850 struct bpf_prog_priv *priv;
851 struct perf_probe_event *pev;
852
853 err = bpf__prepare_probe();
854 if (err) {
855 pr_debug("bpf__prepare_probe failed\n");
856 return err;
857 }
858
859 bpf_object__for_each_program(prog, obj) {
860 err = config_bpf_program(prog);
861 if (err)
862 goto out;
863
864 priv = program_priv(prog);
865 if (IS_ERR_OR_NULL(priv)) {
866 if (!priv)
867 err = -BPF_LOADER_ERRNO__INTERNAL;
868 else
869 err = PTR_ERR(priv);
870 goto out;
871 }
872
873 if (priv->is_tp) {
874 bpf_program__set_type(prog, BPF_PROG_TYPE_TRACEPOINT);
875 continue;
876 }
877
878 bpf_program__set_type(prog, BPF_PROG_TYPE_KPROBE);
879 pev = &priv->pev;
880
881 err = convert_perf_probe_events(pev, 1);
882 if (err < 0) {
883 pr_debug("bpf_probe: failed to convert perf probe events\n");
884 goto out;
885 }
886
887 err = apply_perf_probe_events(pev, 1);
888 if (err < 0) {
889 pr_debug("bpf_probe: failed to apply perf probe events\n");
890 goto out;
891 }
892
893 /*
894 * After probing, let's consider prologue, which
895 * adds program fetcher to BPF programs.
896 *
897 * hook_load_preprocessor() hooks pre-processor
898 * to bpf_program, let it generate prologue
899 * dynamically during loading.
900 */
901 err = hook_load_preprocessor(prog);
902 if (err)
903 goto out;
904 }
905out:
906 return err < 0 ? err : 0;
907}
908
909#define EVENTS_WRITE_BUFSIZE 4096
910int bpf__unprobe(struct bpf_object *obj)
911{
912 int err, ret = 0;
913 struct bpf_program *prog;
914
915 bpf_object__for_each_program(prog, obj) {
916 struct bpf_prog_priv *priv = program_priv(prog);
917 int i;
918
919 if (IS_ERR_OR_NULL(priv) || priv->is_tp)
920 continue;
921
922 for (i = 0; i < priv->pev.ntevs; i++) {
923 struct probe_trace_event *tev = &priv->pev.tevs[i];
924 char name_buf[EVENTS_WRITE_BUFSIZE];
925 struct strfilter *delfilter;
926
927 snprintf(name_buf, EVENTS_WRITE_BUFSIZE,
928 "%s:%s", tev->group, tev->event);
929 name_buf[EVENTS_WRITE_BUFSIZE - 1] = '\0';
930
931 delfilter = strfilter__new(name_buf, NULL);
932 if (!delfilter) {
933 pr_debug("Failed to create filter for unprobing\n");
934 ret = -ENOMEM;
935 continue;
936 }
937
938 err = del_perf_probe_events(delfilter);
939 strfilter__delete(delfilter);
940 if (err) {
941 pr_debug("Failed to delete %s\n", name_buf);
942 ret = err;
943 continue;
944 }
945 }
946 }
947 return ret;
948}
949
950static int bpf_object__load_prologue(struct bpf_object *obj)
951{
952 int init_cnt = ARRAY_SIZE(prologue_init_insn);
953 const struct bpf_insn *orig_insns;
954 struct bpf_preproc_result res;
955 struct perf_probe_event *pev;
956 struct bpf_program *prog;
957 int orig_insns_cnt;
958
959 bpf_object__for_each_program(prog, obj) {
960 struct bpf_prog_priv *priv = program_priv(prog);
961 int err, i, fd;
962
963 if (IS_ERR_OR_NULL(priv)) {
964 pr_debug("bpf: failed to get private field\n");
965 return -BPF_LOADER_ERRNO__INTERNAL;
966 }
967
968 if (!priv->need_prologue)
969 continue;
970
971 /*
972 * For each program that needs prologue we do following:
973 *
974 * - take its current instructions and use them
975 * to generate the new code with prologue
976 * - load new instructions with bpf_prog_load
977 * and keep the fd in prologue_fds
978 * - new fd will be used in bpf__foreach_event
979 * to connect this program with perf evsel
980 */
981 orig_insns = bpf_program__insns(prog);
982 orig_insns_cnt = bpf_program__insn_cnt(prog);
983
984 pev = &priv->pev;
985 for (i = 0; i < pev->ntevs; i++) {
986 /*
987 * Skipping artificall prologue_init_insn instructions
988 * (init_cnt), so the prologue can be generated instead
989 * of them.
990 */
991 err = preproc_gen_prologue(prog, i,
992 orig_insns + init_cnt,
993 orig_insns_cnt - init_cnt,
994 &res);
995 if (err)
996 return err;
997
998 fd = bpf_prog_load(bpf_program__get_type(prog),
999 bpf_program__name(prog), "GPL",
1000 res.new_insn_ptr,
1001 res.new_insn_cnt, NULL);
1002 if (fd < 0) {
1003 char bf[128];
1004
1005 libbpf_strerror(-errno, bf, sizeof(bf));
1006 pr_debug("bpf: load objects with prologue failed: err=%d: (%s)\n",
1007 -errno, bf);
1008 return -errno;
1009 }
1010 priv->prologue_fds[i] = fd;
1011 }
1012 /*
1013 * We no longer need the original program,
1014 * we can unload it.
1015 */
1016 bpf_program__unload(prog);
1017 }
1018 return 0;
1019}
1020
1021int bpf__load(struct bpf_object *obj)
1022{
1023 int err;
1024
1025 err = bpf_object__load(obj);
1026 if (err) {
1027 char bf[128];
1028 libbpf_strerror(err, bf, sizeof(bf));
1029 pr_debug("bpf: load objects failed: err=%d: (%s)\n", err, bf);
1030 return err;
1031 }
1032 return bpf_object__load_prologue(obj);
1033}
1034
1035int bpf__foreach_event(struct bpf_object *obj,
1036 bpf_prog_iter_callback_t func,
1037 void *arg)
1038{
1039 struct bpf_program *prog;
1040 int err;
1041
1042 bpf_object__for_each_program(prog, obj) {
1043 struct bpf_prog_priv *priv = program_priv(prog);
1044 struct probe_trace_event *tev;
1045 struct perf_probe_event *pev;
1046 int i, fd;
1047
1048 if (IS_ERR_OR_NULL(priv)) {
1049 pr_debug("bpf: failed to get private field\n");
1050 return -BPF_LOADER_ERRNO__INTERNAL;
1051 }
1052
1053 if (priv->is_tp) {
1054 fd = bpf_program__fd(prog);
1055 err = (*func)(priv->sys_name, priv->evt_name, fd, obj, arg);
1056 if (err) {
1057 pr_debug("bpf: tracepoint call back failed, stop iterate\n");
1058 return err;
1059 }
1060 continue;
1061 }
1062
1063 pev = &priv->pev;
1064 for (i = 0; i < pev->ntevs; i++) {
1065 tev = &pev->tevs[i];
1066
1067 if (priv->need_prologue)
1068 fd = priv->prologue_fds[i];
1069 else
1070 fd = bpf_program__fd(prog);
1071
1072 if (fd < 0) {
1073 pr_debug("bpf: failed to get file descriptor\n");
1074 return fd;
1075 }
1076
1077 err = (*func)(tev->group, tev->event, fd, obj, arg);
1078 if (err) {
1079 pr_debug("bpf: call back failed, stop iterate\n");
1080 return err;
1081 }
1082 }
1083 }
1084 return 0;
1085}
1086
1087enum bpf_map_op_type {
1088 BPF_MAP_OP_SET_VALUE,
1089 BPF_MAP_OP_SET_EVSEL,
1090};
1091
1092enum bpf_map_key_type {
1093 BPF_MAP_KEY_ALL,
1094 BPF_MAP_KEY_RANGES,
1095};
1096
1097struct bpf_map_op {
1098 struct list_head list;
1099 enum bpf_map_op_type op_type;
1100 enum bpf_map_key_type key_type;
1101 union {
1102 struct parse_events_array array;
1103 } k;
1104 union {
1105 u64 value;
1106 struct evsel *evsel;
1107 } v;
1108};
1109
1110struct bpf_map_priv {
1111 struct list_head ops_list;
1112};
1113
1114static void
1115bpf_map_op__delete(struct bpf_map_op *op)
1116{
1117 if (!list_empty(&op->list))
1118 list_del_init(&op->list);
1119 if (op->key_type == BPF_MAP_KEY_RANGES)
1120 parse_events__clear_array(&op->k.array);
1121 free(op);
1122}
1123
1124static void
1125bpf_map_priv__purge(struct bpf_map_priv *priv)
1126{
1127 struct bpf_map_op *pos, *n;
1128
1129 list_for_each_entry_safe(pos, n, &priv->ops_list, list) {
1130 list_del_init(&pos->list);
1131 bpf_map_op__delete(pos);
1132 }
1133}
1134
1135static void
1136bpf_map_priv__clear(const struct bpf_map *map __maybe_unused,
1137 void *_priv)
1138{
1139 struct bpf_map_priv *priv = _priv;
1140
1141 bpf_map_priv__purge(priv);
1142 free(priv);
1143}
1144
1145static void *map_priv(const struct bpf_map *map)
1146{
1147 void *priv;
1148
1149 if (IS_ERR_OR_NULL(bpf_map_hash))
1150 return NULL;
1151 if (!hashmap__find(bpf_map_hash, map, &priv))
1152 return NULL;
1153 return priv;
1154}
1155
1156static void bpf_map_hash_free(void)
1157{
1158 struct hashmap_entry *cur;
1159 size_t bkt;
1160
1161 if (IS_ERR_OR_NULL(bpf_map_hash))
1162 return;
1163
1164 hashmap__for_each_entry(bpf_map_hash, cur, bkt)
1165 bpf_map_priv__clear(cur->pkey, cur->pvalue);
1166
1167 hashmap__free(bpf_map_hash);
1168 bpf_map_hash = NULL;
1169}
1170
1171static int map_set_priv(struct bpf_map *map, void *priv)
1172{
1173 void *old_priv;
1174
1175 if (WARN_ON_ONCE(IS_ERR(bpf_map_hash)))
1176 return PTR_ERR(bpf_program_hash);
1177
1178 if (!bpf_map_hash) {
1179 bpf_map_hash = hashmap__new(ptr_hash, ptr_equal, NULL);
1180 if (IS_ERR(bpf_map_hash))
1181 return PTR_ERR(bpf_map_hash);
1182 }
1183
1184 old_priv = map_priv(map);
1185 if (old_priv) {
1186 bpf_map_priv__clear(map, old_priv);
1187 return hashmap__set(bpf_map_hash, map, priv, NULL, NULL);
1188 }
1189 return hashmap__add(bpf_map_hash, map, priv);
1190}
1191
1192static int
1193bpf_map_op_setkey(struct bpf_map_op *op, struct parse_events_term *term)
1194{
1195 op->key_type = BPF_MAP_KEY_ALL;
1196 if (!term)
1197 return 0;
1198
1199 if (term->array.nr_ranges) {
1200 size_t memsz = term->array.nr_ranges *
1201 sizeof(op->k.array.ranges[0]);
1202
1203 op->k.array.ranges = memdup(term->array.ranges, memsz);
1204 if (!op->k.array.ranges) {
1205 pr_debug("Not enough memory to alloc indices for map\n");
1206 return -ENOMEM;
1207 }
1208 op->key_type = BPF_MAP_KEY_RANGES;
1209 op->k.array.nr_ranges = term->array.nr_ranges;
1210 }
1211 return 0;
1212}
1213
1214static struct bpf_map_op *
1215bpf_map_op__new(struct parse_events_term *term)
1216{
1217 struct bpf_map_op *op;
1218 int err;
1219
1220 op = zalloc(sizeof(*op));
1221 if (!op) {
1222 pr_debug("Failed to alloc bpf_map_op\n");
1223 return ERR_PTR(-ENOMEM);
1224 }
1225 INIT_LIST_HEAD(&op->list);
1226
1227 err = bpf_map_op_setkey(op, term);
1228 if (err) {
1229 free(op);
1230 return ERR_PTR(err);
1231 }
1232 return op;
1233}
1234
1235static struct bpf_map_op *
1236bpf_map_op__clone(struct bpf_map_op *op)
1237{
1238 struct bpf_map_op *newop;
1239
1240 newop = memdup(op, sizeof(*op));
1241 if (!newop) {
1242 pr_debug("Failed to alloc bpf_map_op\n");
1243 return NULL;
1244 }
1245
1246 INIT_LIST_HEAD(&newop->list);
1247 if (op->key_type == BPF_MAP_KEY_RANGES) {
1248 size_t memsz = op->k.array.nr_ranges *
1249 sizeof(op->k.array.ranges[0]);
1250
1251 newop->k.array.ranges = memdup(op->k.array.ranges, memsz);
1252 if (!newop->k.array.ranges) {
1253 pr_debug("Failed to alloc indices for map\n");
1254 free(newop);
1255 return NULL;
1256 }
1257 }
1258
1259 return newop;
1260}
1261
1262static struct bpf_map_priv *
1263bpf_map_priv__clone(struct bpf_map_priv *priv)
1264{
1265 struct bpf_map_priv *newpriv;
1266 struct bpf_map_op *pos, *newop;
1267
1268 newpriv = zalloc(sizeof(*newpriv));
1269 if (!newpriv) {
1270 pr_debug("Not enough memory to alloc map private\n");
1271 return NULL;
1272 }
1273 INIT_LIST_HEAD(&newpriv->ops_list);
1274
1275 list_for_each_entry(pos, &priv->ops_list, list) {
1276 newop = bpf_map_op__clone(pos);
1277 if (!newop) {
1278 bpf_map_priv__purge(newpriv);
1279 return NULL;
1280 }
1281 list_add_tail(&newop->list, &newpriv->ops_list);
1282 }
1283
1284 return newpriv;
1285}
1286
1287static int
1288bpf_map__add_op(struct bpf_map *map, struct bpf_map_op *op)
1289{
1290 const char *map_name = bpf_map__name(map);
1291 struct bpf_map_priv *priv = map_priv(map);
1292
1293 if (IS_ERR(priv)) {
1294 pr_debug("Failed to get private from map %s\n", map_name);
1295 return PTR_ERR(priv);
1296 }
1297
1298 if (!priv) {
1299 priv = zalloc(sizeof(*priv));
1300 if (!priv) {
1301 pr_debug("Not enough memory to alloc map private\n");
1302 return -ENOMEM;
1303 }
1304 INIT_LIST_HEAD(&priv->ops_list);
1305
1306 if (map_set_priv(map, priv)) {
1307 free(priv);
1308 return -BPF_LOADER_ERRNO__INTERNAL;
1309 }
1310 }
1311
1312 list_add_tail(&op->list, &priv->ops_list);
1313 return 0;
1314}
1315
1316static struct bpf_map_op *
1317bpf_map__add_newop(struct bpf_map *map, struct parse_events_term *term)
1318{
1319 struct bpf_map_op *op;
1320 int err;
1321
1322 op = bpf_map_op__new(term);
1323 if (IS_ERR(op))
1324 return op;
1325
1326 err = bpf_map__add_op(map, op);
1327 if (err) {
1328 bpf_map_op__delete(op);
1329 return ERR_PTR(err);
1330 }
1331 return op;
1332}
1333
1334static int
1335__bpf_map__config_value(struct bpf_map *map,
1336 struct parse_events_term *term)
1337{
1338 struct bpf_map_op *op;
1339 const char *map_name = bpf_map__name(map);
1340
1341 if (!map) {
1342 pr_debug("Map '%s' is invalid\n", map_name);
1343 return -BPF_LOADER_ERRNO__INTERNAL;
1344 }
1345
1346 if (bpf_map__type(map) != BPF_MAP_TYPE_ARRAY) {
1347 pr_debug("Map %s type is not BPF_MAP_TYPE_ARRAY\n",
1348 map_name);
1349 return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1350 }
1351 if (bpf_map__key_size(map) < sizeof(unsigned int)) {
1352 pr_debug("Map %s has incorrect key size\n", map_name);
1353 return -BPF_LOADER_ERRNO__OBJCONF_MAP_KEYSIZE;
1354 }
1355 switch (bpf_map__value_size(map)) {
1356 case 1:
1357 case 2:
1358 case 4:
1359 case 8:
1360 break;
1361 default:
1362 pr_debug("Map %s has incorrect value size\n", map_name);
1363 return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE;
1364 }
1365
1366 op = bpf_map__add_newop(map, term);
1367 if (IS_ERR(op))
1368 return PTR_ERR(op);
1369 op->op_type = BPF_MAP_OP_SET_VALUE;
1370 op->v.value = term->val.num;
1371 return 0;
1372}
1373
1374static int
1375bpf_map__config_value(struct bpf_map *map,
1376 struct parse_events_term *term,
1377 struct evlist *evlist __maybe_unused)
1378{
1379 if (!term->err_val) {
1380 pr_debug("Config value not set\n");
1381 return -BPF_LOADER_ERRNO__OBJCONF_CONF;
1382 }
1383
1384 if (term->type_val != PARSE_EVENTS__TERM_TYPE_NUM) {
1385 pr_debug("ERROR: wrong value type for 'value'\n");
1386 return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE;
1387 }
1388
1389 return __bpf_map__config_value(map, term);
1390}
1391
1392static int
1393__bpf_map__config_event(struct bpf_map *map,
1394 struct parse_events_term *term,
1395 struct evlist *evlist)
1396{
1397 struct bpf_map_op *op;
1398 const char *map_name = bpf_map__name(map);
1399 struct evsel *evsel = evlist__find_evsel_by_str(evlist, term->val.str);
1400
1401 if (!evsel) {
1402 pr_debug("Event (for '%s') '%s' doesn't exist\n",
1403 map_name, term->val.str);
1404 return -BPF_LOADER_ERRNO__OBJCONF_MAP_NOEVT;
1405 }
1406
1407 if (!map) {
1408 pr_debug("Map '%s' is invalid\n", map_name);
1409 return PTR_ERR(map);
1410 }
1411
1412 /*
1413 * No need to check key_size and value_size:
1414 * kernel has already checked them.
1415 */
1416 if (bpf_map__type(map) != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {
1417 pr_debug("Map %s type is not BPF_MAP_TYPE_PERF_EVENT_ARRAY\n",
1418 map_name);
1419 return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1420 }
1421
1422 op = bpf_map__add_newop(map, term);
1423 if (IS_ERR(op))
1424 return PTR_ERR(op);
1425 op->op_type = BPF_MAP_OP_SET_EVSEL;
1426 op->v.evsel = evsel;
1427 return 0;
1428}
1429
1430static int
1431bpf_map__config_event(struct bpf_map *map,
1432 struct parse_events_term *term,
1433 struct evlist *evlist)
1434{
1435 if (!term->err_val) {
1436 pr_debug("Config value not set\n");
1437 return -BPF_LOADER_ERRNO__OBJCONF_CONF;
1438 }
1439
1440 if (term->type_val != PARSE_EVENTS__TERM_TYPE_STR) {
1441 pr_debug("ERROR: wrong value type for 'event'\n");
1442 return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE;
1443 }
1444
1445 return __bpf_map__config_event(map, term, evlist);
1446}
1447
1448struct bpf_obj_config__map_func {
1449 const char *config_opt;
1450 int (*config_func)(struct bpf_map *, struct parse_events_term *,
1451 struct evlist *);
1452};
1453
1454struct bpf_obj_config__map_func bpf_obj_config__map_funcs[] = {
1455 {"value", bpf_map__config_value},
1456 {"event", bpf_map__config_event},
1457};
1458
1459static int
1460config_map_indices_range_check(struct parse_events_term *term,
1461 struct bpf_map *map,
1462 const char *map_name)
1463{
1464 struct parse_events_array *array = &term->array;
1465 unsigned int i;
1466
1467 if (!array->nr_ranges)
1468 return 0;
1469 if (!array->ranges) {
1470 pr_debug("ERROR: map %s: array->nr_ranges is %d but range array is NULL\n",
1471 map_name, (int)array->nr_ranges);
1472 return -BPF_LOADER_ERRNO__INTERNAL;
1473 }
1474
1475 if (!map) {
1476 pr_debug("Map '%s' is invalid\n", map_name);
1477 return -BPF_LOADER_ERRNO__INTERNAL;
1478 }
1479
1480 for (i = 0; i < array->nr_ranges; i++) {
1481 unsigned int start = array->ranges[i].start;
1482 size_t length = array->ranges[i].length;
1483 unsigned int idx = start + length - 1;
1484
1485 if (idx >= bpf_map__max_entries(map)) {
1486 pr_debug("ERROR: index %d too large\n", idx);
1487 return -BPF_LOADER_ERRNO__OBJCONF_MAP_IDX2BIG;
1488 }
1489 }
1490 return 0;
1491}
1492
1493static int
1494bpf__obj_config_map(struct bpf_object *obj,
1495 struct parse_events_term *term,
1496 struct evlist *evlist,
1497 int *key_scan_pos)
1498{
1499 /* key is "map:<mapname>.<config opt>" */
1500 char *map_name = strdup(term->config + sizeof("map:") - 1);
1501 struct bpf_map *map;
1502 int err = -BPF_LOADER_ERRNO__OBJCONF_OPT;
1503 char *map_opt;
1504 size_t i;
1505
1506 if (!map_name)
1507 return -ENOMEM;
1508
1509 map_opt = strchr(map_name, '.');
1510 if (!map_opt) {
1511 pr_debug("ERROR: Invalid map config: %s\n", map_name);
1512 goto out;
1513 }
1514
1515 *map_opt++ = '\0';
1516 if (*map_opt == '\0') {
1517 pr_debug("ERROR: Invalid map option: %s\n", term->config);
1518 goto out;
1519 }
1520
1521 map = bpf_object__find_map_by_name(obj, map_name);
1522 if (!map) {
1523 pr_debug("ERROR: Map %s doesn't exist\n", map_name);
1524 err = -BPF_LOADER_ERRNO__OBJCONF_MAP_NOTEXIST;
1525 goto out;
1526 }
1527
1528 *key_scan_pos += strlen(map_opt);
1529 err = config_map_indices_range_check(term, map, map_name);
1530 if (err)
1531 goto out;
1532 *key_scan_pos -= strlen(map_opt);
1533
1534 for (i = 0; i < ARRAY_SIZE(bpf_obj_config__map_funcs); i++) {
1535 struct bpf_obj_config__map_func *func =
1536 &bpf_obj_config__map_funcs[i];
1537
1538 if (strcmp(map_opt, func->config_opt) == 0) {
1539 err = func->config_func(map, term, evlist);
1540 goto out;
1541 }
1542 }
1543
1544 pr_debug("ERROR: Invalid map config option '%s'\n", map_opt);
1545 err = -BPF_LOADER_ERRNO__OBJCONF_MAP_OPT;
1546out:
1547 if (!err)
1548 *key_scan_pos += strlen(map_opt);
1549
1550 free(map_name);
1551 return err;
1552}
1553
1554int bpf__config_obj(struct bpf_object *obj,
1555 struct parse_events_term *term,
1556 struct evlist *evlist,
1557 int *error_pos)
1558{
1559 int key_scan_pos = 0;
1560 int err;
1561
1562 if (!obj || !term || !term->config)
1563 return -EINVAL;
1564
1565 if (strstarts(term->config, "map:")) {
1566 key_scan_pos = sizeof("map:") - 1;
1567 err = bpf__obj_config_map(obj, term, evlist, &key_scan_pos);
1568 goto out;
1569 }
1570 err = -BPF_LOADER_ERRNO__OBJCONF_OPT;
1571out:
1572 if (error_pos)
1573 *error_pos = key_scan_pos;
1574 return err;
1575
1576}
1577
1578typedef int (*map_config_func_t)(const char *name, int map_fd,
1579 const struct bpf_map *map,
1580 struct bpf_map_op *op,
1581 void *pkey, void *arg);
1582
1583static int
1584foreach_key_array_all(map_config_func_t func,
1585 void *arg, const char *name,
1586 int map_fd, const struct bpf_map *map,
1587 struct bpf_map_op *op)
1588{
1589 unsigned int i;
1590 int err;
1591
1592 for (i = 0; i < bpf_map__max_entries(map); i++) {
1593 err = func(name, map_fd, map, op, &i, arg);
1594 if (err) {
1595 pr_debug("ERROR: failed to insert value to %s[%u]\n",
1596 name, i);
1597 return err;
1598 }
1599 }
1600 return 0;
1601}
1602
1603static int
1604foreach_key_array_ranges(map_config_func_t func, void *arg,
1605 const char *name, int map_fd,
1606 const struct bpf_map *map,
1607 struct bpf_map_op *op)
1608{
1609 unsigned int i, j;
1610 int err;
1611
1612 for (i = 0; i < op->k.array.nr_ranges; i++) {
1613 unsigned int start = op->k.array.ranges[i].start;
1614 size_t length = op->k.array.ranges[i].length;
1615
1616 for (j = 0; j < length; j++) {
1617 unsigned int idx = start + j;
1618
1619 err = func(name, map_fd, map, op, &idx, arg);
1620 if (err) {
1621 pr_debug("ERROR: failed to insert value to %s[%u]\n",
1622 name, idx);
1623 return err;
1624 }
1625 }
1626 }
1627 return 0;
1628}
1629
1630static int
1631bpf_map_config_foreach_key(struct bpf_map *map,
1632 map_config_func_t func,
1633 void *arg)
1634{
1635 int err, map_fd, type;
1636 struct bpf_map_op *op;
1637 const char *name = bpf_map__name(map);
1638 struct bpf_map_priv *priv = map_priv(map);
1639
1640 if (IS_ERR(priv)) {
1641 pr_debug("ERROR: failed to get private from map %s\n", name);
1642 return -BPF_LOADER_ERRNO__INTERNAL;
1643 }
1644 if (!priv || list_empty(&priv->ops_list)) {
1645 pr_debug("INFO: nothing to config for map %s\n", name);
1646 return 0;
1647 }
1648
1649 if (!map) {
1650 pr_debug("Map '%s' is invalid\n", name);
1651 return -BPF_LOADER_ERRNO__INTERNAL;
1652 }
1653 map_fd = bpf_map__fd(map);
1654 if (map_fd < 0) {
1655 pr_debug("ERROR: failed to get fd from map %s\n", name);
1656 return map_fd;
1657 }
1658
1659 type = bpf_map__type(map);
1660 list_for_each_entry(op, &priv->ops_list, list) {
1661 switch (type) {
1662 case BPF_MAP_TYPE_ARRAY:
1663 case BPF_MAP_TYPE_PERF_EVENT_ARRAY:
1664 switch (op->key_type) {
1665 case BPF_MAP_KEY_ALL:
1666 err = foreach_key_array_all(func, arg, name,
1667 map_fd, map, op);
1668 break;
1669 case BPF_MAP_KEY_RANGES:
1670 err = foreach_key_array_ranges(func, arg, name,
1671 map_fd, map, op);
1672 break;
1673 default:
1674 pr_debug("ERROR: keytype for map '%s' invalid\n",
1675 name);
1676 return -BPF_LOADER_ERRNO__INTERNAL;
1677 }
1678 if (err)
1679 return err;
1680 break;
1681 default:
1682 pr_debug("ERROR: type of '%s' incorrect\n", name);
1683 return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1684 }
1685 }
1686
1687 return 0;
1688}
1689
1690static int
1691apply_config_value_for_key(int map_fd, void *pkey,
1692 size_t val_size, u64 val)
1693{
1694 int err = 0;
1695
1696 switch (val_size) {
1697 case 1: {
1698 u8 _val = (u8)(val);
1699 err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1700 break;
1701 }
1702 case 2: {
1703 u16 _val = (u16)(val);
1704 err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1705 break;
1706 }
1707 case 4: {
1708 u32 _val = (u32)(val);
1709 err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1710 break;
1711 }
1712 case 8: {
1713 err = bpf_map_update_elem(map_fd, pkey, &val, BPF_ANY);
1714 break;
1715 }
1716 default:
1717 pr_debug("ERROR: invalid value size\n");
1718 return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE;
1719 }
1720 if (err && errno)
1721 err = -errno;
1722 return err;
1723}
1724
1725static int
1726apply_config_evsel_for_key(const char *name, int map_fd, void *pkey,
1727 struct evsel *evsel)
1728{
1729 struct xyarray *xy = evsel->core.fd;
1730 struct perf_event_attr *attr;
1731 unsigned int key, events;
1732 bool check_pass = false;
1733 int *evt_fd;
1734 int err;
1735
1736 if (!xy) {
1737 pr_debug("ERROR: evsel not ready for map %s\n", name);
1738 return -BPF_LOADER_ERRNO__INTERNAL;
1739 }
1740
1741 if (xy->row_size / xy->entry_size != 1) {
1742 pr_debug("ERROR: Dimension of target event is incorrect for map %s\n",
1743 name);
1744 return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTDIM;
1745 }
1746
1747 attr = &evsel->core.attr;
1748 if (attr->inherit) {
1749 pr_debug("ERROR: Can't put inherit event into map %s\n", name);
1750 return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTINH;
1751 }
1752
1753 if (evsel__is_bpf_output(evsel))
1754 check_pass = true;
1755 if (attr->type == PERF_TYPE_RAW)
1756 check_pass = true;
1757 if (attr->type == PERF_TYPE_HARDWARE)
1758 check_pass = true;
1759 if (!check_pass) {
1760 pr_debug("ERROR: Event type is wrong for map %s\n", name);
1761 return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTTYPE;
1762 }
1763
1764 events = xy->entries / (xy->row_size / xy->entry_size);
1765 key = *((unsigned int *)pkey);
1766 if (key >= events) {
1767 pr_debug("ERROR: there is no event %d for map %s\n",
1768 key, name);
1769 return -BPF_LOADER_ERRNO__OBJCONF_MAP_MAPSIZE;
1770 }
1771 evt_fd = xyarray__entry(xy, key, 0);
1772 err = bpf_map_update_elem(map_fd, pkey, evt_fd, BPF_ANY);
1773 if (err && errno)
1774 err = -errno;
1775 return err;
1776}
1777
1778static int
1779apply_obj_config_map_for_key(const char *name, int map_fd,
1780 const struct bpf_map *map,
1781 struct bpf_map_op *op,
1782 void *pkey, void *arg __maybe_unused)
1783{
1784 int err;
1785
1786 switch (op->op_type) {
1787 case BPF_MAP_OP_SET_VALUE:
1788 err = apply_config_value_for_key(map_fd, pkey,
1789 bpf_map__value_size(map),
1790 op->v.value);
1791 break;
1792 case BPF_MAP_OP_SET_EVSEL:
1793 err = apply_config_evsel_for_key(name, map_fd, pkey,
1794 op->v.evsel);
1795 break;
1796 default:
1797 pr_debug("ERROR: unknown value type for '%s'\n", name);
1798 err = -BPF_LOADER_ERRNO__INTERNAL;
1799 }
1800 return err;
1801}
1802
1803static int
1804apply_obj_config_map(struct bpf_map *map)
1805{
1806 return bpf_map_config_foreach_key(map,
1807 apply_obj_config_map_for_key,
1808 NULL);
1809}
1810
1811static int
1812apply_obj_config_object(struct bpf_object *obj)
1813{
1814 struct bpf_map *map;
1815 int err;
1816
1817 bpf_object__for_each_map(map, obj) {
1818 err = apply_obj_config_map(map);
1819 if (err)
1820 return err;
1821 }
1822 return 0;
1823}
1824
1825int bpf__apply_obj_config(void)
1826{
1827 struct bpf_perf_object *perf_obj, *tmp;
1828 int err;
1829
1830 bpf_perf_object__for_each(perf_obj, tmp) {
1831 err = apply_obj_config_object(perf_obj->obj);
1832 if (err)
1833 return err;
1834 }
1835
1836 return 0;
1837}
1838
1839#define bpf__perf_for_each_map(map, pobj, tmp) \
1840 bpf_perf_object__for_each(pobj, tmp) \
1841 bpf_object__for_each_map(map, pobj->obj)
1842
1843#define bpf__perf_for_each_map_named(map, pobj, pobjtmp, name) \
1844 bpf__perf_for_each_map(map, pobj, pobjtmp) \
1845 if (bpf_map__name(map) && (strcmp(name, bpf_map__name(map)) == 0))
1846
1847struct evsel *bpf__setup_output_event(struct evlist *evlist, const char *name)
1848{
1849 struct bpf_map_priv *tmpl_priv = NULL;
1850 struct bpf_perf_object *perf_obj, *tmp;
1851 struct evsel *evsel = NULL;
1852 struct bpf_map *map;
1853 int err;
1854 bool need_init = false;
1855
1856 bpf__perf_for_each_map_named(map, perf_obj, tmp, name) {
1857 struct bpf_map_priv *priv = map_priv(map);
1858
1859 if (IS_ERR(priv))
1860 return ERR_PTR(-BPF_LOADER_ERRNO__INTERNAL);
1861
1862 /*
1863 * No need to check map type: type should have been
1864 * verified by kernel.
1865 */
1866 if (!need_init && !priv)
1867 need_init = !priv;
1868 if (!tmpl_priv && priv)
1869 tmpl_priv = priv;
1870 }
1871
1872 if (!need_init)
1873 return NULL;
1874
1875 if (!tmpl_priv) {
1876 char *event_definition = NULL;
1877
1878 if (asprintf(&event_definition, "bpf-output/no-inherit=1,name=%s/", name) < 0)
1879 return ERR_PTR(-ENOMEM);
1880
1881 err = parse_event(evlist, event_definition);
1882 free(event_definition);
1883
1884 if (err) {
1885 pr_debug("ERROR: failed to create the \"%s\" bpf-output event\n", name);
1886 return ERR_PTR(-err);
1887 }
1888
1889 evsel = evlist__last(evlist);
1890 }
1891
1892 bpf__perf_for_each_map_named(map, perf_obj, tmp, name) {
1893 struct bpf_map_priv *priv = map_priv(map);
1894
1895 if (IS_ERR(priv))
1896 return ERR_PTR(-BPF_LOADER_ERRNO__INTERNAL);
1897 if (priv)
1898 continue;
1899
1900 if (tmpl_priv) {
1901 priv = bpf_map_priv__clone(tmpl_priv);
1902 if (!priv)
1903 return ERR_PTR(-ENOMEM);
1904
1905 err = map_set_priv(map, priv);
1906 if (err) {
1907 bpf_map_priv__clear(map, priv);
1908 return ERR_PTR(err);
1909 }
1910 } else if (evsel) {
1911 struct bpf_map_op *op;
1912
1913 op = bpf_map__add_newop(map, NULL);
1914 if (IS_ERR(op))
1915 return ERR_CAST(op);
1916 op->op_type = BPF_MAP_OP_SET_EVSEL;
1917 op->v.evsel = evsel;
1918 }
1919 }
1920
1921 return evsel;
1922}
1923
1924int bpf__setup_stdout(struct evlist *evlist)
1925{
1926 struct evsel *evsel = bpf__setup_output_event(evlist, "__bpf_stdout__");
1927 return PTR_ERR_OR_ZERO(evsel);
1928}
1929
1930#define ERRNO_OFFSET(e) ((e) - __BPF_LOADER_ERRNO__START)
1931#define ERRCODE_OFFSET(c) ERRNO_OFFSET(BPF_LOADER_ERRNO__##c)
1932#define NR_ERRNO (__BPF_LOADER_ERRNO__END - __BPF_LOADER_ERRNO__START)
1933
1934static const char *bpf_loader_strerror_table[NR_ERRNO] = {
1935 [ERRCODE_OFFSET(CONFIG)] = "Invalid config string",
1936 [ERRCODE_OFFSET(GROUP)] = "Invalid group name",
1937 [ERRCODE_OFFSET(EVENTNAME)] = "No event name found in config string",
1938 [ERRCODE_OFFSET(INTERNAL)] = "BPF loader internal error",
1939 [ERRCODE_OFFSET(COMPILE)] = "Error when compiling BPF scriptlet",
1940 [ERRCODE_OFFSET(PROGCONF_TERM)] = "Invalid program config term in config string",
1941 [ERRCODE_OFFSET(PROLOGUE)] = "Failed to generate prologue",
1942 [ERRCODE_OFFSET(PROLOGUE2BIG)] = "Prologue too big for program",
1943 [ERRCODE_OFFSET(PROLOGUEOOB)] = "Offset out of bound for prologue",
1944 [ERRCODE_OFFSET(OBJCONF_OPT)] = "Invalid object config option",
1945 [ERRCODE_OFFSET(OBJCONF_CONF)] = "Config value not set (missing '=')",
1946 [ERRCODE_OFFSET(OBJCONF_MAP_OPT)] = "Invalid object map config option",
1947 [ERRCODE_OFFSET(OBJCONF_MAP_NOTEXIST)] = "Target map doesn't exist",
1948 [ERRCODE_OFFSET(OBJCONF_MAP_VALUE)] = "Incorrect value type for map",
1949 [ERRCODE_OFFSET(OBJCONF_MAP_TYPE)] = "Incorrect map type",
1950 [ERRCODE_OFFSET(OBJCONF_MAP_KEYSIZE)] = "Incorrect map key size",
1951 [ERRCODE_OFFSET(OBJCONF_MAP_VALUESIZE)] = "Incorrect map value size",
1952 [ERRCODE_OFFSET(OBJCONF_MAP_NOEVT)] = "Event not found for map setting",
1953 [ERRCODE_OFFSET(OBJCONF_MAP_MAPSIZE)] = "Invalid map size for event setting",
1954 [ERRCODE_OFFSET(OBJCONF_MAP_EVTDIM)] = "Event dimension too large",
1955 [ERRCODE_OFFSET(OBJCONF_MAP_EVTINH)] = "Doesn't support inherit event",
1956 [ERRCODE_OFFSET(OBJCONF_MAP_EVTTYPE)] = "Wrong event type for map",
1957 [ERRCODE_OFFSET(OBJCONF_MAP_IDX2BIG)] = "Index too large",
1958};
1959
1960static int
1961bpf_loader_strerror(int err, char *buf, size_t size)
1962{
1963 char sbuf[STRERR_BUFSIZE];
1964 const char *msg;
1965
1966 if (!buf || !size)
1967 return -1;
1968
1969 err = err > 0 ? err : -err;
1970
1971 if (err >= __LIBBPF_ERRNO__START)
1972 return libbpf_strerror(err, buf, size);
1973
1974 if (err >= __BPF_LOADER_ERRNO__START && err < __BPF_LOADER_ERRNO__END) {
1975 msg = bpf_loader_strerror_table[ERRNO_OFFSET(err)];
1976 snprintf(buf, size, "%s", msg);
1977 buf[size - 1] = '\0';
1978 return 0;
1979 }
1980
1981 if (err >= __BPF_LOADER_ERRNO__END)
1982 snprintf(buf, size, "Unknown bpf loader error %d", err);
1983 else
1984 snprintf(buf, size, "%s",
1985 str_error_r(err, sbuf, sizeof(sbuf)));
1986
1987 buf[size - 1] = '\0';
1988 return -1;
1989}
1990
1991#define bpf__strerror_head(err, buf, size) \
1992 char sbuf[STRERR_BUFSIZE], *emsg;\
1993 if (!size)\
1994 return 0;\
1995 if (err < 0)\
1996 err = -err;\
1997 bpf_loader_strerror(err, sbuf, sizeof(sbuf));\
1998 emsg = sbuf;\
1999 switch (err) {\
2000 default:\
2001 scnprintf(buf, size, "%s", emsg);\
2002 break;
2003
2004#define bpf__strerror_entry(val, fmt...)\
2005 case val: {\
2006 scnprintf(buf, size, fmt);\
2007 break;\
2008 }
2009
2010#define bpf__strerror_end(buf, size)\
2011 }\
2012 buf[size - 1] = '\0';
2013
2014int bpf__strerror_prepare_load(const char *filename, bool source,
2015 int err, char *buf, size_t size)
2016{
2017 size_t n;
2018 int ret;
2019
2020 n = snprintf(buf, size, "Failed to load %s%s: ",
2021 filename, source ? " from source" : "");
2022 if (n >= size) {
2023 buf[size - 1] = '\0';
2024 return 0;
2025 }
2026 buf += n;
2027 size -= n;
2028
2029 ret = bpf_loader_strerror(err, buf, size);
2030 buf[size - 1] = '\0';
2031 return ret;
2032}
2033
2034int bpf__strerror_probe(struct bpf_object *obj __maybe_unused,
2035 int err, char *buf, size_t size)
2036{
2037 bpf__strerror_head(err, buf, size);
2038 case BPF_LOADER_ERRNO__PROGCONF_TERM: {
2039 scnprintf(buf, size, "%s (add -v to see detail)", emsg);
2040 break;
2041 }
2042 bpf__strerror_entry(EEXIST, "Probe point exist. Try 'perf probe -d \"*\"' and set 'force=yes'");
2043 bpf__strerror_entry(EACCES, "You need to be root");
2044 bpf__strerror_entry(EPERM, "You need to be root, and /proc/sys/kernel/kptr_restrict should be 0");
2045 bpf__strerror_entry(ENOENT, "You need to check probing points in BPF file");
2046 bpf__strerror_end(buf, size);
2047 return 0;
2048}
2049
2050int bpf__strerror_load(struct bpf_object *obj,
2051 int err, char *buf, size_t size)
2052{
2053 bpf__strerror_head(err, buf, size);
2054 case LIBBPF_ERRNO__KVER: {
2055 unsigned int obj_kver = bpf_object__kversion(obj);
2056 unsigned int real_kver;
2057
2058 if (fetch_kernel_version(&real_kver, NULL, 0)) {
2059 scnprintf(buf, size, "Unable to fetch kernel version");
2060 break;
2061 }
2062
2063 if (obj_kver != real_kver) {
2064 scnprintf(buf, size,
2065 "'version' ("KVER_FMT") doesn't match running kernel ("KVER_FMT")",
2066 KVER_PARAM(obj_kver),
2067 KVER_PARAM(real_kver));
2068 break;
2069 }
2070
2071 scnprintf(buf, size, "Failed to load program for unknown reason");
2072 break;
2073 }
2074 bpf__strerror_end(buf, size);
2075 return 0;
2076}
2077
2078int bpf__strerror_config_obj(struct bpf_object *obj __maybe_unused,
2079 struct parse_events_term *term __maybe_unused,
2080 struct evlist *evlist __maybe_unused,
2081 int *error_pos __maybe_unused, int err,
2082 char *buf, size_t size)
2083{
2084 bpf__strerror_head(err, buf, size);
2085 bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE,
2086 "Can't use this config term with this map type");
2087 bpf__strerror_end(buf, size);
2088 return 0;
2089}
2090
2091int bpf__strerror_apply_obj_config(int err, char *buf, size_t size)
2092{
2093 bpf__strerror_head(err, buf, size);
2094 bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTDIM,
2095 "Cannot set event to BPF map in multi-thread tracing");
2096 bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTINH,
2097 "%s (Hint: use -i to turn off inherit)", emsg);
2098 bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTTYPE,
2099 "Can only put raw, hardware and BPF output event into a BPF map");
2100 bpf__strerror_end(buf, size);
2101 return 0;
2102}
2103
2104int bpf__strerror_setup_output_event(struct evlist *evlist __maybe_unused,
2105 int err, char *buf, size_t size)
2106{
2107 bpf__strerror_head(err, buf, size);
2108 bpf__strerror_end(buf, size);
2109 return 0;
2110}