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v4.10.11
 
   1/*
   2 * bpf-loader.c
   3 *
   4 * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
   5 * Copyright (C) 2015 Huawei Inc.
   6 */
   7
   8#include <linux/bpf.h>
   9#include <bpf/libbpf.h>
  10#include <bpf/bpf.h>
  11#include <linux/err.h>
 
  12#include <linux/string.h>
  13#include "perf.h"
 
 
  14#include "debug.h"
 
  15#include "bpf-loader.h"
  16#include "bpf-prologue.h"
  17#include "probe-event.h"
  18#include "probe-finder.h" // for MAX_PROBES
  19#include "parse-events.h"
 
 
  20#include "llvm-utils.h"
  21#include "c++/clang-c.h"
  22
  23#define DEFINE_PRINT_FN(name, level) \
  24static int libbpf_##name(const char *fmt, ...)	\
  25{						\
  26	va_list args;				\
  27	int ret;				\
  28						\
  29	va_start(args, fmt);			\
  30	ret = veprintf(level, verbose, pr_fmt(fmt), args);\
  31	va_end(args);				\
  32	return ret;				\
  33}
  34
  35DEFINE_PRINT_FN(warning, 1)
  36DEFINE_PRINT_FN(info, 1)
  37DEFINE_PRINT_FN(debug, 1)
 
 
  38
  39struct bpf_prog_priv {
  40	bool is_tp;
  41	char *sys_name;
  42	char *evt_name;
  43	struct perf_probe_event pev;
  44	bool need_prologue;
  45	struct bpf_insn *insns_buf;
  46	int nr_types;
  47	int *type_mapping;
  48};
  49
  50static bool libbpf_initialized;
  51
  52struct bpf_object *
  53bpf__prepare_load_buffer(void *obj_buf, size_t obj_buf_sz, const char *name)
  54{
  55	struct bpf_object *obj;
  56
  57	if (!libbpf_initialized) {
  58		libbpf_set_print(libbpf_warning,
  59				 libbpf_info,
  60				 libbpf_debug);
  61		libbpf_initialized = true;
  62	}
  63
  64	obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, name);
  65	if (IS_ERR(obj)) {
  66		pr_debug("bpf: failed to load buffer\n");
  67		return ERR_PTR(-EINVAL);
  68	}
  69
  70	return obj;
  71}
  72
  73struct bpf_object *bpf__prepare_load(const char *filename, bool source)
  74{
  75	struct bpf_object *obj;
  76
  77	if (!libbpf_initialized) {
  78		libbpf_set_print(libbpf_warning,
  79				 libbpf_info,
  80				 libbpf_debug);
  81		libbpf_initialized = true;
  82	}
  83
  84	if (source) {
  85		int err;
  86		void *obj_buf;
  87		size_t obj_buf_sz;
  88
  89		perf_clang__init();
  90		err = perf_clang__compile_bpf(filename, &obj_buf, &obj_buf_sz);
  91		perf_clang__cleanup();
  92		if (err) {
  93			pr_warning("bpf: builtin compilation failed: %d, try external compiler\n", err);
  94			err = llvm__compile_bpf(filename, &obj_buf, &obj_buf_sz);
  95			if (err)
  96				return ERR_PTR(-BPF_LOADER_ERRNO__COMPILE);
  97		} else
  98			pr_debug("bpf: successfull builtin compilation\n");
  99		obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, filename);
 100
 101		if (!IS_ERR(obj) && llvm_param.dump_obj)
 102			llvm__dump_obj(filename, obj_buf, obj_buf_sz);
 103
 104		free(obj_buf);
 105	} else
 106		obj = bpf_object__open(filename);
 107
 108	if (IS_ERR(obj)) {
 109		pr_debug("bpf: failed to load %s\n", filename);
 110		return obj;
 111	}
 112
 113	return obj;
 114}
 115
 116void bpf__clear(void)
 117{
 118	struct bpf_object *obj, *tmp;
 119
 120	bpf_object__for_each_safe(obj, tmp) {
 121		bpf__unprobe(obj);
 122		bpf_object__close(obj);
 123	}
 124}
 125
 126static void
 127clear_prog_priv(struct bpf_program *prog __maybe_unused,
 128		void *_priv)
 129{
 130	struct bpf_prog_priv *priv = _priv;
 131
 132	cleanup_perf_probe_events(&priv->pev, 1);
 133	zfree(&priv->insns_buf);
 134	zfree(&priv->type_mapping);
 135	zfree(&priv->sys_name);
 136	zfree(&priv->evt_name);
 137	free(priv);
 138}
 139
 140static int
 141prog_config__exec(const char *value, struct perf_probe_event *pev)
 142{
 143	pev->uprobes = true;
 144	pev->target = strdup(value);
 145	if (!pev->target)
 146		return -ENOMEM;
 147	return 0;
 148}
 149
 150static int
 151prog_config__module(const char *value, struct perf_probe_event *pev)
 152{
 153	pev->uprobes = false;
 154	pev->target = strdup(value);
 155	if (!pev->target)
 156		return -ENOMEM;
 157	return 0;
 158}
 159
 160static int
 161prog_config__bool(const char *value, bool *pbool, bool invert)
 162{
 163	int err;
 164	bool bool_value;
 165
 166	if (!pbool)
 167		return -EINVAL;
 168
 169	err = strtobool(value, &bool_value);
 170	if (err)
 171		return err;
 172
 173	*pbool = invert ? !bool_value : bool_value;
 174	return 0;
 175}
 176
 177static int
 178prog_config__inlines(const char *value,
 179		     struct perf_probe_event *pev __maybe_unused)
 180{
 181	return prog_config__bool(value, &probe_conf.no_inlines, true);
 182}
 183
 184static int
 185prog_config__force(const char *value,
 186		   struct perf_probe_event *pev __maybe_unused)
 187{
 188	return prog_config__bool(value, &probe_conf.force_add, false);
 189}
 190
 191static struct {
 192	const char *key;
 193	const char *usage;
 194	const char *desc;
 195	int (*func)(const char *, struct perf_probe_event *);
 196} bpf_prog_config_terms[] = {
 197	{
 198		.key	= "exec",
 199		.usage	= "exec=<full path of file>",
 200		.desc	= "Set uprobe target",
 201		.func	= prog_config__exec,
 202	},
 203	{
 204		.key	= "module",
 205		.usage	= "module=<module name>    ",
 206		.desc	= "Set kprobe module",
 207		.func	= prog_config__module,
 208	},
 209	{
 210		.key	= "inlines",
 211		.usage	= "inlines=[yes|no]        ",
 212		.desc	= "Probe at inline symbol",
 213		.func	= prog_config__inlines,
 214	},
 215	{
 216		.key	= "force",
 217		.usage	= "force=[yes|no]          ",
 218		.desc	= "Forcibly add events with existing name",
 219		.func	= prog_config__force,
 220	},
 221};
 222
 223static int
 224do_prog_config(const char *key, const char *value,
 225	       struct perf_probe_event *pev)
 226{
 227	unsigned int i;
 228
 229	pr_debug("config bpf program: %s=%s\n", key, value);
 230	for (i = 0; i < ARRAY_SIZE(bpf_prog_config_terms); i++)
 231		if (strcmp(key, bpf_prog_config_terms[i].key) == 0)
 232			return bpf_prog_config_terms[i].func(value, pev);
 233
 234	pr_debug("BPF: ERROR: invalid program config option: %s=%s\n",
 235		 key, value);
 236
 237	pr_debug("\nHint: Valid options are:\n");
 238	for (i = 0; i < ARRAY_SIZE(bpf_prog_config_terms); i++)
 239		pr_debug("\t%s:\t%s\n", bpf_prog_config_terms[i].usage,
 240			 bpf_prog_config_terms[i].desc);
 241	pr_debug("\n");
 242
 243	return -BPF_LOADER_ERRNO__PROGCONF_TERM;
 244}
 245
 246static const char *
 247parse_prog_config_kvpair(const char *config_str, struct perf_probe_event *pev)
 248{
 249	char *text = strdup(config_str);
 250	char *sep, *line;
 251	const char *main_str = NULL;
 252	int err = 0;
 253
 254	if (!text) {
 255		pr_debug("Not enough memory: dup config_str failed\n");
 256		return ERR_PTR(-ENOMEM);
 257	}
 258
 259	line = text;
 260	while ((sep = strchr(line, ';'))) {
 261		char *equ;
 262
 263		*sep = '\0';
 264		equ = strchr(line, '=');
 265		if (!equ) {
 266			pr_warning("WARNING: invalid config in BPF object: %s\n",
 267				   line);
 268			pr_warning("\tShould be 'key=value'.\n");
 269			goto nextline;
 270		}
 271		*equ = '\0';
 272
 273		err = do_prog_config(line, equ + 1, pev);
 274		if (err)
 275			break;
 276nextline:
 277		line = sep + 1;
 278	}
 279
 280	if (!err)
 281		main_str = config_str + (line - text);
 282	free(text);
 283
 284	return err ? ERR_PTR(err) : main_str;
 285}
 286
 287static int
 288parse_prog_config(const char *config_str, const char **p_main_str,
 289		  bool *is_tp, struct perf_probe_event *pev)
 290{
 291	int err;
 292	const char *main_str = parse_prog_config_kvpair(config_str, pev);
 293
 294	if (IS_ERR(main_str))
 295		return PTR_ERR(main_str);
 296
 297	*p_main_str = main_str;
 298	if (!strchr(main_str, '=')) {
 299		/* Is a tracepoint event? */
 300		const char *s = strchr(main_str, ':');
 301
 302		if (!s) {
 303			pr_debug("bpf: '%s' is not a valid tracepoint\n",
 304				 config_str);
 305			return -BPF_LOADER_ERRNO__CONFIG;
 306		}
 307
 308		*is_tp = true;
 309		return 0;
 310	}
 311
 312	*is_tp = false;
 313	err = parse_perf_probe_command(main_str, pev);
 314	if (err < 0) {
 315		pr_debug("bpf: '%s' is not a valid config string\n",
 316			 config_str);
 317		/* parse failed, don't need clear pev. */
 318		return -BPF_LOADER_ERRNO__CONFIG;
 319	}
 320	return 0;
 321}
 322
 323static int
 324config_bpf_program(struct bpf_program *prog)
 325{
 326	struct perf_probe_event *pev = NULL;
 327	struct bpf_prog_priv *priv = NULL;
 328	const char *config_str, *main_str;
 329	bool is_tp = false;
 330	int err;
 331
 332	/* Initialize per-program probing setting */
 333	probe_conf.no_inlines = false;
 334	probe_conf.force_add = false;
 335
 336	config_str = bpf_program__title(prog, false);
 337	if (IS_ERR(config_str)) {
 338		pr_debug("bpf: unable to get title for program\n");
 339		return PTR_ERR(config_str);
 340	}
 341
 342	priv = calloc(sizeof(*priv), 1);
 343	if (!priv) {
 344		pr_debug("bpf: failed to alloc priv\n");
 345		return -ENOMEM;
 346	}
 347	pev = &priv->pev;
 348
 
 349	pr_debug("bpf: config program '%s'\n", config_str);
 350	err = parse_prog_config(config_str, &main_str, &is_tp, pev);
 351	if (err)
 352		goto errout;
 353
 354	if (is_tp) {
 355		char *s = strchr(main_str, ':');
 356
 357		priv->is_tp = true;
 358		priv->sys_name = strndup(main_str, s - main_str);
 359		priv->evt_name = strdup(s + 1);
 360		goto set_priv;
 361	}
 362
 363	if (pev->group && strcmp(pev->group, PERF_BPF_PROBE_GROUP)) {
 364		pr_debug("bpf: '%s': group for event is set and not '%s'.\n",
 365			 config_str, PERF_BPF_PROBE_GROUP);
 366		err = -BPF_LOADER_ERRNO__GROUP;
 367		goto errout;
 368	} else if (!pev->group)
 369		pev->group = strdup(PERF_BPF_PROBE_GROUP);
 370
 371	if (!pev->group) {
 372		pr_debug("bpf: strdup failed\n");
 373		err = -ENOMEM;
 374		goto errout;
 375	}
 376
 377	if (!pev->event) {
 378		pr_debug("bpf: '%s': event name is missing. Section name should be 'key=value'\n",
 379			 config_str);
 380		err = -BPF_LOADER_ERRNO__EVENTNAME;
 381		goto errout;
 382	}
 383	pr_debug("bpf: config '%s' is ok\n", config_str);
 384
 385set_priv:
 386	err = bpf_program__set_priv(prog, priv, clear_prog_priv);
 387	if (err) {
 388		pr_debug("Failed to set priv for program '%s'\n", config_str);
 389		goto errout;
 390	}
 391
 392	return 0;
 393
 394errout:
 395	if (pev)
 396		clear_perf_probe_event(pev);
 397	free(priv);
 398	return err;
 399}
 400
 401static int bpf__prepare_probe(void)
 402{
 403	static int err = 0;
 404	static bool initialized = false;
 405
 406	/*
 407	 * Make err static, so if init failed the first, bpf__prepare_probe()
 408	 * fails each time without calling init_probe_symbol_maps multiple
 409	 * times.
 410	 */
 411	if (initialized)
 412		return err;
 413
 414	initialized = true;
 415	err = init_probe_symbol_maps(false);
 416	if (err < 0)
 417		pr_debug("Failed to init_probe_symbol_maps\n");
 418	probe_conf.max_probes = MAX_PROBES;
 419	return err;
 420}
 421
 422static int
 423preproc_gen_prologue(struct bpf_program *prog, int n,
 424		     struct bpf_insn *orig_insns, int orig_insns_cnt,
 425		     struct bpf_prog_prep_result *res)
 426{
 427	struct bpf_prog_priv *priv = bpf_program__priv(prog);
 428	struct probe_trace_event *tev;
 429	struct perf_probe_event *pev;
 430	struct bpf_insn *buf;
 431	size_t prologue_cnt = 0;
 432	int i, err;
 433
 434	if (IS_ERR(priv) || !priv || priv->is_tp)
 435		goto errout;
 436
 437	pev = &priv->pev;
 438
 439	if (n < 0 || n >= priv->nr_types)
 440		goto errout;
 441
 442	/* Find a tev belongs to that type */
 443	for (i = 0; i < pev->ntevs; i++) {
 444		if (priv->type_mapping[i] == n)
 445			break;
 446	}
 447
 448	if (i >= pev->ntevs) {
 449		pr_debug("Internal error: prologue type %d not found\n", n);
 450		return -BPF_LOADER_ERRNO__PROLOGUE;
 451	}
 452
 453	tev = &pev->tevs[i];
 454
 455	buf = priv->insns_buf;
 456	err = bpf__gen_prologue(tev->args, tev->nargs,
 457				buf, &prologue_cnt,
 458				BPF_MAXINSNS - orig_insns_cnt);
 459	if (err) {
 460		const char *title;
 461
 462		title = bpf_program__title(prog, false);
 463		if (!title)
 464			title = "[unknown]";
 465
 466		pr_debug("Failed to generate prologue for program %s\n",
 467			 title);
 468		return err;
 469	}
 470
 471	memcpy(&buf[prologue_cnt], orig_insns,
 472	       sizeof(struct bpf_insn) * orig_insns_cnt);
 473
 474	res->new_insn_ptr = buf;
 475	res->new_insn_cnt = prologue_cnt + orig_insns_cnt;
 476	res->pfd = NULL;
 477	return 0;
 478
 479errout:
 480	pr_debug("Internal error in preproc_gen_prologue\n");
 481	return -BPF_LOADER_ERRNO__PROLOGUE;
 482}
 483
 484/*
 485 * compare_tev_args is reflexive, transitive and antisymmetric.
 486 * I can proof it but this margin is too narrow to contain.
 487 */
 488static int compare_tev_args(const void *ptev1, const void *ptev2)
 489{
 490	int i, ret;
 491	const struct probe_trace_event *tev1 =
 492		*(const struct probe_trace_event **)ptev1;
 493	const struct probe_trace_event *tev2 =
 494		*(const struct probe_trace_event **)ptev2;
 495
 496	ret = tev2->nargs - tev1->nargs;
 497	if (ret)
 498		return ret;
 499
 500	for (i = 0; i < tev1->nargs; i++) {
 501		struct probe_trace_arg *arg1, *arg2;
 502		struct probe_trace_arg_ref *ref1, *ref2;
 503
 504		arg1 = &tev1->args[i];
 505		arg2 = &tev2->args[i];
 506
 507		ret = strcmp(arg1->value, arg2->value);
 508		if (ret)
 509			return ret;
 510
 511		ref1 = arg1->ref;
 512		ref2 = arg2->ref;
 513
 514		while (ref1 && ref2) {
 515			ret = ref2->offset - ref1->offset;
 516			if (ret)
 517				return ret;
 518
 519			ref1 = ref1->next;
 520			ref2 = ref2->next;
 521		}
 522
 523		if (ref1 || ref2)
 524			return ref2 ? 1 : -1;
 525	}
 526
 527	return 0;
 528}
 529
 530/*
 531 * Assign a type number to each tevs in a pev.
 532 * mapping is an array with same slots as tevs in that pev.
 533 * nr_types will be set to number of types.
 534 */
 535static int map_prologue(struct perf_probe_event *pev, int *mapping,
 536			int *nr_types)
 537{
 538	int i, type = 0;
 539	struct probe_trace_event **ptevs;
 540
 541	size_t array_sz = sizeof(*ptevs) * pev->ntevs;
 542
 543	ptevs = malloc(array_sz);
 544	if (!ptevs) {
 545		pr_debug("Not enough memory: alloc ptevs failed\n");
 546		return -ENOMEM;
 547	}
 548
 549	pr_debug("In map_prologue, ntevs=%d\n", pev->ntevs);
 550	for (i = 0; i < pev->ntevs; i++)
 551		ptevs[i] = &pev->tevs[i];
 552
 553	qsort(ptevs, pev->ntevs, sizeof(*ptevs),
 554	      compare_tev_args);
 555
 556	for (i = 0; i < pev->ntevs; i++) {
 557		int n;
 558
 559		n = ptevs[i] - pev->tevs;
 560		if (i == 0) {
 561			mapping[n] = type;
 562			pr_debug("mapping[%d]=%d\n", n, type);
 563			continue;
 564		}
 565
 566		if (compare_tev_args(ptevs + i, ptevs + i - 1) == 0)
 567			mapping[n] = type;
 568		else
 569			mapping[n] = ++type;
 570
 571		pr_debug("mapping[%d]=%d\n", n, mapping[n]);
 572	}
 573	free(ptevs);
 574	*nr_types = type + 1;
 575
 576	return 0;
 577}
 578
 579static int hook_load_preprocessor(struct bpf_program *prog)
 580{
 581	struct bpf_prog_priv *priv = bpf_program__priv(prog);
 582	struct perf_probe_event *pev;
 583	bool need_prologue = false;
 584	int err, i;
 585
 586	if (IS_ERR(priv) || !priv) {
 587		pr_debug("Internal error when hook preprocessor\n");
 588		return -BPF_LOADER_ERRNO__INTERNAL;
 589	}
 590
 591	if (priv->is_tp) {
 592		priv->need_prologue = false;
 593		return 0;
 594	}
 595
 596	pev = &priv->pev;
 597	for (i = 0; i < pev->ntevs; i++) {
 598		struct probe_trace_event *tev = &pev->tevs[i];
 599
 600		if (tev->nargs > 0) {
 601			need_prologue = true;
 602			break;
 603		}
 604	}
 605
 606	/*
 607	 * Since all tevs don't have argument, we don't need generate
 608	 * prologue.
 609	 */
 610	if (!need_prologue) {
 611		priv->need_prologue = false;
 612		return 0;
 613	}
 614
 615	priv->need_prologue = true;
 616	priv->insns_buf = malloc(sizeof(struct bpf_insn) * BPF_MAXINSNS);
 617	if (!priv->insns_buf) {
 618		pr_debug("Not enough memory: alloc insns_buf failed\n");
 619		return -ENOMEM;
 620	}
 621
 622	priv->type_mapping = malloc(sizeof(int) * pev->ntevs);
 623	if (!priv->type_mapping) {
 624		pr_debug("Not enough memory: alloc type_mapping failed\n");
 625		return -ENOMEM;
 626	}
 627	memset(priv->type_mapping, -1,
 628	       sizeof(int) * pev->ntevs);
 629
 630	err = map_prologue(pev, priv->type_mapping, &priv->nr_types);
 631	if (err)
 632		return err;
 633
 634	err = bpf_program__set_prep(prog, priv->nr_types,
 635				    preproc_gen_prologue);
 636	return err;
 637}
 638
 639int bpf__probe(struct bpf_object *obj)
 640{
 641	int err = 0;
 642	struct bpf_program *prog;
 643	struct bpf_prog_priv *priv;
 644	struct perf_probe_event *pev;
 645
 646	err = bpf__prepare_probe();
 647	if (err) {
 648		pr_debug("bpf__prepare_probe failed\n");
 649		return err;
 650	}
 651
 652	bpf_object__for_each_program(prog, obj) {
 653		err = config_bpf_program(prog);
 654		if (err)
 655			goto out;
 656
 657		priv = bpf_program__priv(prog);
 658		if (IS_ERR(priv) || !priv) {
 659			err = PTR_ERR(priv);
 660			goto out;
 661		}
 662
 663		if (priv->is_tp) {
 664			bpf_program__set_tracepoint(prog);
 665			continue;
 666		}
 667
 668		bpf_program__set_kprobe(prog);
 669		pev = &priv->pev;
 670
 671		err = convert_perf_probe_events(pev, 1);
 672		if (err < 0) {
 673			pr_debug("bpf_probe: failed to convert perf probe events");
 674			goto out;
 675		}
 676
 677		err = apply_perf_probe_events(pev, 1);
 678		if (err < 0) {
 679			pr_debug("bpf_probe: failed to apply perf probe events");
 680			goto out;
 681		}
 682
 683		/*
 684		 * After probing, let's consider prologue, which
 685		 * adds program fetcher to BPF programs.
 686		 *
 687		 * hook_load_preprocessorr() hooks pre-processor
 688		 * to bpf_program, let it generate prologue
 689		 * dynamically during loading.
 690		 */
 691		err = hook_load_preprocessor(prog);
 692		if (err)
 693			goto out;
 694	}
 695out:
 696	return err < 0 ? err : 0;
 697}
 698
 699#define EVENTS_WRITE_BUFSIZE  4096
 700int bpf__unprobe(struct bpf_object *obj)
 701{
 702	int err, ret = 0;
 703	struct bpf_program *prog;
 704
 705	bpf_object__for_each_program(prog, obj) {
 706		struct bpf_prog_priv *priv = bpf_program__priv(prog);
 707		int i;
 708
 709		if (IS_ERR(priv) || !priv || priv->is_tp)
 710			continue;
 711
 712		for (i = 0; i < priv->pev.ntevs; i++) {
 713			struct probe_trace_event *tev = &priv->pev.tevs[i];
 714			char name_buf[EVENTS_WRITE_BUFSIZE];
 715			struct strfilter *delfilter;
 716
 717			snprintf(name_buf, EVENTS_WRITE_BUFSIZE,
 718				 "%s:%s", tev->group, tev->event);
 719			name_buf[EVENTS_WRITE_BUFSIZE - 1] = '\0';
 720
 721			delfilter = strfilter__new(name_buf, NULL);
 722			if (!delfilter) {
 723				pr_debug("Failed to create filter for unprobing\n");
 724				ret = -ENOMEM;
 725				continue;
 726			}
 727
 728			err = del_perf_probe_events(delfilter);
 729			strfilter__delete(delfilter);
 730			if (err) {
 731				pr_debug("Failed to delete %s\n", name_buf);
 732				ret = err;
 733				continue;
 734			}
 735		}
 736	}
 737	return ret;
 738}
 739
 740int bpf__load(struct bpf_object *obj)
 741{
 742	int err;
 743
 744	err = bpf_object__load(obj);
 745	if (err) {
 746		pr_debug("bpf: load objects failed\n");
 
 
 747		return err;
 748	}
 749	return 0;
 750}
 751
 752int bpf__foreach_event(struct bpf_object *obj,
 753		       bpf_prog_iter_callback_t func,
 754		       void *arg)
 755{
 756	struct bpf_program *prog;
 757	int err;
 758
 759	bpf_object__for_each_program(prog, obj) {
 760		struct bpf_prog_priv *priv = bpf_program__priv(prog);
 761		struct probe_trace_event *tev;
 762		struct perf_probe_event *pev;
 763		int i, fd;
 764
 765		if (IS_ERR(priv) || !priv) {
 766			pr_debug("bpf: failed to get private field\n");
 767			return -BPF_LOADER_ERRNO__INTERNAL;
 768		}
 769
 770		if (priv->is_tp) {
 771			fd = bpf_program__fd(prog);
 772			err = (*func)(priv->sys_name, priv->evt_name, fd, arg);
 773			if (err) {
 774				pr_debug("bpf: tracepoint call back failed, stop iterate\n");
 775				return err;
 776			}
 777			continue;
 778		}
 779
 780		pev = &priv->pev;
 781		for (i = 0; i < pev->ntevs; i++) {
 782			tev = &pev->tevs[i];
 783
 784			if (priv->need_prologue) {
 785				int type = priv->type_mapping[i];
 786
 787				fd = bpf_program__nth_fd(prog, type);
 788			} else {
 789				fd = bpf_program__fd(prog);
 790			}
 791
 792			if (fd < 0) {
 793				pr_debug("bpf: failed to get file descriptor\n");
 794				return fd;
 795			}
 796
 797			err = (*func)(tev->group, tev->event, fd, arg);
 798			if (err) {
 799				pr_debug("bpf: call back failed, stop iterate\n");
 800				return err;
 801			}
 802		}
 803	}
 804	return 0;
 805}
 806
 807enum bpf_map_op_type {
 808	BPF_MAP_OP_SET_VALUE,
 809	BPF_MAP_OP_SET_EVSEL,
 810};
 811
 812enum bpf_map_key_type {
 813	BPF_MAP_KEY_ALL,
 814	BPF_MAP_KEY_RANGES,
 815};
 816
 817struct bpf_map_op {
 818	struct list_head list;
 819	enum bpf_map_op_type op_type;
 820	enum bpf_map_key_type key_type;
 821	union {
 822		struct parse_events_array array;
 823	} k;
 824	union {
 825		u64 value;
 826		struct perf_evsel *evsel;
 827	} v;
 828};
 829
 830struct bpf_map_priv {
 831	struct list_head ops_list;
 832};
 833
 834static void
 835bpf_map_op__delete(struct bpf_map_op *op)
 836{
 837	if (!list_empty(&op->list))
 838		list_del(&op->list);
 839	if (op->key_type == BPF_MAP_KEY_RANGES)
 840		parse_events__clear_array(&op->k.array);
 841	free(op);
 842}
 843
 844static void
 845bpf_map_priv__purge(struct bpf_map_priv *priv)
 846{
 847	struct bpf_map_op *pos, *n;
 848
 849	list_for_each_entry_safe(pos, n, &priv->ops_list, list) {
 850		list_del_init(&pos->list);
 851		bpf_map_op__delete(pos);
 852	}
 853}
 854
 855static void
 856bpf_map_priv__clear(struct bpf_map *map __maybe_unused,
 857		    void *_priv)
 858{
 859	struct bpf_map_priv *priv = _priv;
 860
 861	bpf_map_priv__purge(priv);
 862	free(priv);
 863}
 864
 865static int
 866bpf_map_op_setkey(struct bpf_map_op *op, struct parse_events_term *term)
 867{
 868	op->key_type = BPF_MAP_KEY_ALL;
 869	if (!term)
 870		return 0;
 871
 872	if (term->array.nr_ranges) {
 873		size_t memsz = term->array.nr_ranges *
 874				sizeof(op->k.array.ranges[0]);
 875
 876		op->k.array.ranges = memdup(term->array.ranges, memsz);
 877		if (!op->k.array.ranges) {
 878			pr_debug("Not enough memory to alloc indices for map\n");
 879			return -ENOMEM;
 880		}
 881		op->key_type = BPF_MAP_KEY_RANGES;
 882		op->k.array.nr_ranges = term->array.nr_ranges;
 883	}
 884	return 0;
 885}
 886
 887static struct bpf_map_op *
 888bpf_map_op__new(struct parse_events_term *term)
 889{
 890	struct bpf_map_op *op;
 891	int err;
 892
 893	op = zalloc(sizeof(*op));
 894	if (!op) {
 895		pr_debug("Failed to alloc bpf_map_op\n");
 896		return ERR_PTR(-ENOMEM);
 897	}
 898	INIT_LIST_HEAD(&op->list);
 899
 900	err = bpf_map_op_setkey(op, term);
 901	if (err) {
 902		free(op);
 903		return ERR_PTR(err);
 904	}
 905	return op;
 906}
 907
 908static struct bpf_map_op *
 909bpf_map_op__clone(struct bpf_map_op *op)
 910{
 911	struct bpf_map_op *newop;
 912
 913	newop = memdup(op, sizeof(*op));
 914	if (!newop) {
 915		pr_debug("Failed to alloc bpf_map_op\n");
 916		return NULL;
 917	}
 918
 919	INIT_LIST_HEAD(&newop->list);
 920	if (op->key_type == BPF_MAP_KEY_RANGES) {
 921		size_t memsz = op->k.array.nr_ranges *
 922			       sizeof(op->k.array.ranges[0]);
 923
 924		newop->k.array.ranges = memdup(op->k.array.ranges, memsz);
 925		if (!newop->k.array.ranges) {
 926			pr_debug("Failed to alloc indices for map\n");
 927			free(newop);
 928			return NULL;
 929		}
 930	}
 931
 932	return newop;
 933}
 934
 935static struct bpf_map_priv *
 936bpf_map_priv__clone(struct bpf_map_priv *priv)
 937{
 938	struct bpf_map_priv *newpriv;
 939	struct bpf_map_op *pos, *newop;
 940
 941	newpriv = zalloc(sizeof(*newpriv));
 942	if (!newpriv) {
 943		pr_debug("Not enough memory to alloc map private\n");
 944		return NULL;
 945	}
 946	INIT_LIST_HEAD(&newpriv->ops_list);
 947
 948	list_for_each_entry(pos, &priv->ops_list, list) {
 949		newop = bpf_map_op__clone(pos);
 950		if (!newop) {
 951			bpf_map_priv__purge(newpriv);
 952			return NULL;
 953		}
 954		list_add_tail(&newop->list, &newpriv->ops_list);
 955	}
 956
 957	return newpriv;
 958}
 959
 960static int
 961bpf_map__add_op(struct bpf_map *map, struct bpf_map_op *op)
 962{
 963	const char *map_name = bpf_map__name(map);
 964	struct bpf_map_priv *priv = bpf_map__priv(map);
 965
 966	if (IS_ERR(priv)) {
 967		pr_debug("Failed to get private from map %s\n", map_name);
 968		return PTR_ERR(priv);
 969	}
 970
 971	if (!priv) {
 972		priv = zalloc(sizeof(*priv));
 973		if (!priv) {
 974			pr_debug("Not enough memory to alloc map private\n");
 975			return -ENOMEM;
 976		}
 977		INIT_LIST_HEAD(&priv->ops_list);
 978
 979		if (bpf_map__set_priv(map, priv, bpf_map_priv__clear)) {
 980			free(priv);
 981			return -BPF_LOADER_ERRNO__INTERNAL;
 982		}
 983	}
 984
 985	list_add_tail(&op->list, &priv->ops_list);
 986	return 0;
 987}
 988
 989static struct bpf_map_op *
 990bpf_map__add_newop(struct bpf_map *map, struct parse_events_term *term)
 991{
 992	struct bpf_map_op *op;
 993	int err;
 994
 995	op = bpf_map_op__new(term);
 996	if (IS_ERR(op))
 997		return op;
 998
 999	err = bpf_map__add_op(map, op);
1000	if (err) {
1001		bpf_map_op__delete(op);
1002		return ERR_PTR(err);
1003	}
1004	return op;
1005}
1006
1007static int
1008__bpf_map__config_value(struct bpf_map *map,
1009			struct parse_events_term *term)
1010{
1011	struct bpf_map_op *op;
1012	const char *map_name = bpf_map__name(map);
1013	const struct bpf_map_def *def = bpf_map__def(map);
1014
1015	if (IS_ERR(def)) {
1016		pr_debug("Unable to get map definition from '%s'\n",
1017			 map_name);
1018		return -BPF_LOADER_ERRNO__INTERNAL;
1019	}
1020
1021	if (def->type != BPF_MAP_TYPE_ARRAY) {
1022		pr_debug("Map %s type is not BPF_MAP_TYPE_ARRAY\n",
1023			 map_name);
1024		return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1025	}
1026	if (def->key_size < sizeof(unsigned int)) {
1027		pr_debug("Map %s has incorrect key size\n", map_name);
1028		return -BPF_LOADER_ERRNO__OBJCONF_MAP_KEYSIZE;
1029	}
1030	switch (def->value_size) {
1031	case 1:
1032	case 2:
1033	case 4:
1034	case 8:
1035		break;
1036	default:
1037		pr_debug("Map %s has incorrect value size\n", map_name);
1038		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE;
1039	}
1040
1041	op = bpf_map__add_newop(map, term);
1042	if (IS_ERR(op))
1043		return PTR_ERR(op);
1044	op->op_type = BPF_MAP_OP_SET_VALUE;
1045	op->v.value = term->val.num;
1046	return 0;
1047}
1048
1049static int
1050bpf_map__config_value(struct bpf_map *map,
1051		      struct parse_events_term *term,
1052		      struct perf_evlist *evlist __maybe_unused)
1053{
1054	if (!term->err_val) {
1055		pr_debug("Config value not set\n");
1056		return -BPF_LOADER_ERRNO__OBJCONF_CONF;
1057	}
1058
1059	if (term->type_val != PARSE_EVENTS__TERM_TYPE_NUM) {
1060		pr_debug("ERROR: wrong value type for 'value'\n");
1061		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE;
1062	}
1063
1064	return __bpf_map__config_value(map, term);
1065}
1066
1067static int
1068__bpf_map__config_event(struct bpf_map *map,
1069			struct parse_events_term *term,
1070			struct perf_evlist *evlist)
1071{
1072	struct perf_evsel *evsel;
1073	const struct bpf_map_def *def;
1074	struct bpf_map_op *op;
1075	const char *map_name = bpf_map__name(map);
 
1076
1077	evsel = perf_evlist__find_evsel_by_str(evlist, term->val.str);
1078	if (!evsel) {
1079		pr_debug("Event (for '%s') '%s' doesn't exist\n",
1080			 map_name, term->val.str);
1081		return -BPF_LOADER_ERRNO__OBJCONF_MAP_NOEVT;
1082	}
1083
1084	def = bpf_map__def(map);
1085	if (IS_ERR(def)) {
1086		pr_debug("Unable to get map definition from '%s'\n",
1087			 map_name);
1088		return PTR_ERR(def);
1089	}
1090
1091	/*
1092	 * No need to check key_size and value_size:
1093	 * kernel has already checked them.
1094	 */
1095	if (def->type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {
1096		pr_debug("Map %s type is not BPF_MAP_TYPE_PERF_EVENT_ARRAY\n",
1097			 map_name);
1098		return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1099	}
1100
1101	op = bpf_map__add_newop(map, term);
1102	if (IS_ERR(op))
1103		return PTR_ERR(op);
1104	op->op_type = BPF_MAP_OP_SET_EVSEL;
1105	op->v.evsel = evsel;
1106	return 0;
1107}
1108
1109static int
1110bpf_map__config_event(struct bpf_map *map,
1111		      struct parse_events_term *term,
1112		      struct perf_evlist *evlist)
1113{
1114	if (!term->err_val) {
1115		pr_debug("Config value not set\n");
1116		return -BPF_LOADER_ERRNO__OBJCONF_CONF;
1117	}
1118
1119	if (term->type_val != PARSE_EVENTS__TERM_TYPE_STR) {
1120		pr_debug("ERROR: wrong value type for 'event'\n");
1121		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE;
1122	}
1123
1124	return __bpf_map__config_event(map, term, evlist);
1125}
1126
1127struct bpf_obj_config__map_func {
1128	const char *config_opt;
1129	int (*config_func)(struct bpf_map *, struct parse_events_term *,
1130			   struct perf_evlist *);
1131};
1132
1133struct bpf_obj_config__map_func bpf_obj_config__map_funcs[] = {
1134	{"value", bpf_map__config_value},
1135	{"event", bpf_map__config_event},
1136};
1137
1138static int
1139config_map_indices_range_check(struct parse_events_term *term,
1140			       struct bpf_map *map,
1141			       const char *map_name)
1142{
1143	struct parse_events_array *array = &term->array;
1144	const struct bpf_map_def *def;
1145	unsigned int i;
1146
1147	if (!array->nr_ranges)
1148		return 0;
1149	if (!array->ranges) {
1150		pr_debug("ERROR: map %s: array->nr_ranges is %d but range array is NULL\n",
1151			 map_name, (int)array->nr_ranges);
1152		return -BPF_LOADER_ERRNO__INTERNAL;
1153	}
1154
1155	def = bpf_map__def(map);
1156	if (IS_ERR(def)) {
1157		pr_debug("ERROR: Unable to get map definition from '%s'\n",
1158			 map_name);
1159		return -BPF_LOADER_ERRNO__INTERNAL;
1160	}
1161
1162	for (i = 0; i < array->nr_ranges; i++) {
1163		unsigned int start = array->ranges[i].start;
1164		size_t length = array->ranges[i].length;
1165		unsigned int idx = start + length - 1;
1166
1167		if (idx >= def->max_entries) {
1168			pr_debug("ERROR: index %d too large\n", idx);
1169			return -BPF_LOADER_ERRNO__OBJCONF_MAP_IDX2BIG;
1170		}
1171	}
1172	return 0;
1173}
1174
1175static int
1176bpf__obj_config_map(struct bpf_object *obj,
1177		    struct parse_events_term *term,
1178		    struct perf_evlist *evlist,
1179		    int *key_scan_pos)
1180{
1181	/* key is "map:<mapname>.<config opt>" */
1182	char *map_name = strdup(term->config + sizeof("map:") - 1);
1183	struct bpf_map *map;
1184	int err = -BPF_LOADER_ERRNO__OBJCONF_OPT;
1185	char *map_opt;
1186	size_t i;
1187
1188	if (!map_name)
1189		return -ENOMEM;
1190
1191	map_opt = strchr(map_name, '.');
1192	if (!map_opt) {
1193		pr_debug("ERROR: Invalid map config: %s\n", map_name);
1194		goto out;
1195	}
1196
1197	*map_opt++ = '\0';
1198	if (*map_opt == '\0') {
1199		pr_debug("ERROR: Invalid map option: %s\n", term->config);
1200		goto out;
1201	}
1202
1203	map = bpf_object__find_map_by_name(obj, map_name);
1204	if (!map) {
1205		pr_debug("ERROR: Map %s doesn't exist\n", map_name);
1206		err = -BPF_LOADER_ERRNO__OBJCONF_MAP_NOTEXIST;
1207		goto out;
1208	}
1209
1210	*key_scan_pos += strlen(map_opt);
1211	err = config_map_indices_range_check(term, map, map_name);
1212	if (err)
1213		goto out;
1214	*key_scan_pos -= strlen(map_opt);
1215
1216	for (i = 0; i < ARRAY_SIZE(bpf_obj_config__map_funcs); i++) {
1217		struct bpf_obj_config__map_func *func =
1218				&bpf_obj_config__map_funcs[i];
1219
1220		if (strcmp(map_opt, func->config_opt) == 0) {
1221			err = func->config_func(map, term, evlist);
1222			goto out;
1223		}
1224	}
1225
1226	pr_debug("ERROR: Invalid map config option '%s'\n", map_opt);
1227	err = -BPF_LOADER_ERRNO__OBJCONF_MAP_OPT;
1228out:
1229	free(map_name);
1230	if (!err)
1231		key_scan_pos += strlen(map_opt);
1232	return err;
1233}
1234
1235int bpf__config_obj(struct bpf_object *obj,
1236		    struct parse_events_term *term,
1237		    struct perf_evlist *evlist,
1238		    int *error_pos)
1239{
1240	int key_scan_pos = 0;
1241	int err;
1242
1243	if (!obj || !term || !term->config)
1244		return -EINVAL;
1245
1246	if (!prefixcmp(term->config, "map:")) {
1247		key_scan_pos = sizeof("map:") - 1;
1248		err = bpf__obj_config_map(obj, term, evlist, &key_scan_pos);
1249		goto out;
1250	}
1251	err = -BPF_LOADER_ERRNO__OBJCONF_OPT;
1252out:
1253	if (error_pos)
1254		*error_pos = key_scan_pos;
1255	return err;
1256
1257}
1258
1259typedef int (*map_config_func_t)(const char *name, int map_fd,
1260				 const struct bpf_map_def *pdef,
1261				 struct bpf_map_op *op,
1262				 void *pkey, void *arg);
1263
1264static int
1265foreach_key_array_all(map_config_func_t func,
1266		      void *arg, const char *name,
1267		      int map_fd, const struct bpf_map_def *pdef,
1268		      struct bpf_map_op *op)
1269{
1270	unsigned int i;
1271	int err;
1272
1273	for (i = 0; i < pdef->max_entries; i++) {
1274		err = func(name, map_fd, pdef, op, &i, arg);
1275		if (err) {
1276			pr_debug("ERROR: failed to insert value to %s[%u]\n",
1277				 name, i);
1278			return err;
1279		}
1280	}
1281	return 0;
1282}
1283
1284static int
1285foreach_key_array_ranges(map_config_func_t func, void *arg,
1286			 const char *name, int map_fd,
1287			 const struct bpf_map_def *pdef,
1288			 struct bpf_map_op *op)
1289{
1290	unsigned int i, j;
1291	int err;
1292
1293	for (i = 0; i < op->k.array.nr_ranges; i++) {
1294		unsigned int start = op->k.array.ranges[i].start;
1295		size_t length = op->k.array.ranges[i].length;
1296
1297		for (j = 0; j < length; j++) {
1298			unsigned int idx = start + j;
1299
1300			err = func(name, map_fd, pdef, op, &idx, arg);
1301			if (err) {
1302				pr_debug("ERROR: failed to insert value to %s[%u]\n",
1303					 name, idx);
1304				return err;
1305			}
1306		}
1307	}
1308	return 0;
1309}
1310
1311static int
1312bpf_map_config_foreach_key(struct bpf_map *map,
1313			   map_config_func_t func,
1314			   void *arg)
1315{
1316	int err, map_fd;
1317	struct bpf_map_op *op;
1318	const struct bpf_map_def *def;
1319	const char *name = bpf_map__name(map);
1320	struct bpf_map_priv *priv = bpf_map__priv(map);
1321
1322	if (IS_ERR(priv)) {
1323		pr_debug("ERROR: failed to get private from map %s\n", name);
1324		return -BPF_LOADER_ERRNO__INTERNAL;
1325	}
1326	if (!priv || list_empty(&priv->ops_list)) {
1327		pr_debug("INFO: nothing to config for map %s\n", name);
1328		return 0;
1329	}
1330
1331	def = bpf_map__def(map);
1332	if (IS_ERR(def)) {
1333		pr_debug("ERROR: failed to get definition from map %s\n", name);
1334		return -BPF_LOADER_ERRNO__INTERNAL;
1335	}
1336	map_fd = bpf_map__fd(map);
1337	if (map_fd < 0) {
1338		pr_debug("ERROR: failed to get fd from map %s\n", name);
1339		return map_fd;
1340	}
1341
1342	list_for_each_entry(op, &priv->ops_list, list) {
1343		switch (def->type) {
1344		case BPF_MAP_TYPE_ARRAY:
1345		case BPF_MAP_TYPE_PERF_EVENT_ARRAY:
1346			switch (op->key_type) {
1347			case BPF_MAP_KEY_ALL:
1348				err = foreach_key_array_all(func, arg, name,
1349							    map_fd, def, op);
1350				break;
1351			case BPF_MAP_KEY_RANGES:
1352				err = foreach_key_array_ranges(func, arg, name,
1353							       map_fd, def,
1354							       op);
1355				break;
1356			default:
1357				pr_debug("ERROR: keytype for map '%s' invalid\n",
1358					 name);
1359				return -BPF_LOADER_ERRNO__INTERNAL;
1360			}
1361			if (err)
1362				return err;
1363			break;
1364		default:
1365			pr_debug("ERROR: type of '%s' incorrect\n", name);
1366			return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1367		}
1368	}
1369
1370	return 0;
1371}
1372
1373static int
1374apply_config_value_for_key(int map_fd, void *pkey,
1375			   size_t val_size, u64 val)
1376{
1377	int err = 0;
1378
1379	switch (val_size) {
1380	case 1: {
1381		u8 _val = (u8)(val);
1382		err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1383		break;
1384	}
1385	case 2: {
1386		u16 _val = (u16)(val);
1387		err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1388		break;
1389	}
1390	case 4: {
1391		u32 _val = (u32)(val);
1392		err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1393		break;
1394	}
1395	case 8: {
1396		err = bpf_map_update_elem(map_fd, pkey, &val, BPF_ANY);
1397		break;
1398	}
1399	default:
1400		pr_debug("ERROR: invalid value size\n");
1401		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE;
1402	}
1403	if (err && errno)
1404		err = -errno;
1405	return err;
1406}
1407
1408static int
1409apply_config_evsel_for_key(const char *name, int map_fd, void *pkey,
1410			   struct perf_evsel *evsel)
1411{
1412	struct xyarray *xy = evsel->fd;
1413	struct perf_event_attr *attr;
1414	unsigned int key, events;
1415	bool check_pass = false;
1416	int *evt_fd;
1417	int err;
1418
1419	if (!xy) {
1420		pr_debug("ERROR: evsel not ready for map %s\n", name);
1421		return -BPF_LOADER_ERRNO__INTERNAL;
1422	}
1423
1424	if (xy->row_size / xy->entry_size != 1) {
1425		pr_debug("ERROR: Dimension of target event is incorrect for map %s\n",
1426			 name);
1427		return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTDIM;
1428	}
1429
1430	attr = &evsel->attr;
1431	if (attr->inherit) {
1432		pr_debug("ERROR: Can't put inherit event into map %s\n", name);
1433		return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTINH;
1434	}
1435
1436	if (perf_evsel__is_bpf_output(evsel))
1437		check_pass = true;
1438	if (attr->type == PERF_TYPE_RAW)
1439		check_pass = true;
1440	if (attr->type == PERF_TYPE_HARDWARE)
1441		check_pass = true;
1442	if (!check_pass) {
1443		pr_debug("ERROR: Event type is wrong for map %s\n", name);
1444		return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTTYPE;
1445	}
1446
1447	events = xy->entries / (xy->row_size / xy->entry_size);
1448	key = *((unsigned int *)pkey);
1449	if (key >= events) {
1450		pr_debug("ERROR: there is no event %d for map %s\n",
1451			 key, name);
1452		return -BPF_LOADER_ERRNO__OBJCONF_MAP_MAPSIZE;
1453	}
1454	evt_fd = xyarray__entry(xy, key, 0);
1455	err = bpf_map_update_elem(map_fd, pkey, evt_fd, BPF_ANY);
1456	if (err && errno)
1457		err = -errno;
1458	return err;
1459}
1460
1461static int
1462apply_obj_config_map_for_key(const char *name, int map_fd,
1463			     const struct bpf_map_def *pdef,
1464			     struct bpf_map_op *op,
1465			     void *pkey, void *arg __maybe_unused)
1466{
1467	int err;
1468
1469	switch (op->op_type) {
1470	case BPF_MAP_OP_SET_VALUE:
1471		err = apply_config_value_for_key(map_fd, pkey,
1472						 pdef->value_size,
1473						 op->v.value);
1474		break;
1475	case BPF_MAP_OP_SET_EVSEL:
1476		err = apply_config_evsel_for_key(name, map_fd, pkey,
1477						 op->v.evsel);
1478		break;
1479	default:
1480		pr_debug("ERROR: unknown value type for '%s'\n", name);
1481		err = -BPF_LOADER_ERRNO__INTERNAL;
1482	}
1483	return err;
1484}
1485
1486static int
1487apply_obj_config_map(struct bpf_map *map)
1488{
1489	return bpf_map_config_foreach_key(map,
1490					  apply_obj_config_map_for_key,
1491					  NULL);
1492}
1493
1494static int
1495apply_obj_config_object(struct bpf_object *obj)
1496{
1497	struct bpf_map *map;
1498	int err;
1499
1500	bpf_map__for_each(map, obj) {
1501		err = apply_obj_config_map(map);
1502		if (err)
1503			return err;
1504	}
1505	return 0;
1506}
1507
1508int bpf__apply_obj_config(void)
1509{
1510	struct bpf_object *obj, *tmp;
1511	int err;
1512
1513	bpf_object__for_each_safe(obj, tmp) {
1514		err = apply_obj_config_object(obj);
1515		if (err)
1516			return err;
1517	}
1518
1519	return 0;
1520}
1521
1522#define bpf__for_each_map(pos, obj, objtmp)	\
1523	bpf_object__for_each_safe(obj, objtmp)	\
1524		bpf_map__for_each(pos, obj)
1525
1526#define bpf__for_each_stdout_map(pos, obj, objtmp)	\
1527	bpf__for_each_map(pos, obj, objtmp) 		\
1528		if (bpf_map__name(pos) && 		\
1529			(strcmp("__bpf_stdout__", 	\
1530				bpf_map__name(pos)) == 0))
1531
1532int bpf__setup_stdout(struct perf_evlist *evlist __maybe_unused)
1533{
1534	struct bpf_map_priv *tmpl_priv = NULL;
1535	struct bpf_object *obj, *tmp;
1536	struct perf_evsel *evsel = NULL;
1537	struct bpf_map *map;
1538	int err;
1539	bool need_init = false;
1540
1541	bpf__for_each_stdout_map(map, obj, tmp) {
1542		struct bpf_map_priv *priv = bpf_map__priv(map);
1543
1544		if (IS_ERR(priv))
1545			return -BPF_LOADER_ERRNO__INTERNAL;
1546
1547		/*
1548		 * No need to check map type: type should have been
1549		 * verified by kernel.
1550		 */
1551		if (!need_init && !priv)
1552			need_init = !priv;
1553		if (!tmpl_priv && priv)
1554			tmpl_priv = priv;
1555	}
1556
1557	if (!need_init)
1558		return 0;
1559
1560	if (!tmpl_priv) {
1561		err = parse_events(evlist, "bpf-output/no-inherit=1,name=__bpf_stdout__/",
1562				   NULL);
 
 
 
 
 
 
1563		if (err) {
1564			pr_debug("ERROR: failed to create bpf-output event\n");
1565			return -err;
1566		}
1567
1568		evsel = perf_evlist__last(evlist);
1569	}
1570
1571	bpf__for_each_stdout_map(map, obj, tmp) {
1572		struct bpf_map_priv *priv = bpf_map__priv(map);
1573
1574		if (IS_ERR(priv))
1575			return -BPF_LOADER_ERRNO__INTERNAL;
1576		if (priv)
1577			continue;
1578
1579		if (tmpl_priv) {
1580			priv = bpf_map_priv__clone(tmpl_priv);
1581			if (!priv)
1582				return -ENOMEM;
1583
1584			err = bpf_map__set_priv(map, priv, bpf_map_priv__clear);
1585			if (err) {
1586				bpf_map_priv__clear(map, priv);
1587				return err;
1588			}
1589		} else if (evsel) {
1590			struct bpf_map_op *op;
1591
1592			op = bpf_map__add_newop(map, NULL);
1593			if (IS_ERR(op))
1594				return PTR_ERR(op);
1595			op->op_type = BPF_MAP_OP_SET_EVSEL;
1596			op->v.evsel = evsel;
1597		}
1598	}
1599
1600	return 0;
 
 
 
 
 
 
1601}
1602
1603#define ERRNO_OFFSET(e)		((e) - __BPF_LOADER_ERRNO__START)
1604#define ERRCODE_OFFSET(c)	ERRNO_OFFSET(BPF_LOADER_ERRNO__##c)
1605#define NR_ERRNO	(__BPF_LOADER_ERRNO__END - __BPF_LOADER_ERRNO__START)
1606
1607static const char *bpf_loader_strerror_table[NR_ERRNO] = {
1608	[ERRCODE_OFFSET(CONFIG)]	= "Invalid config string",
1609	[ERRCODE_OFFSET(GROUP)]		= "Invalid group name",
1610	[ERRCODE_OFFSET(EVENTNAME)]	= "No event name found in config string",
1611	[ERRCODE_OFFSET(INTERNAL)]	= "BPF loader internal error",
1612	[ERRCODE_OFFSET(COMPILE)]	= "Error when compiling BPF scriptlet",
1613	[ERRCODE_OFFSET(PROGCONF_TERM)]	= "Invalid program config term in config string",
1614	[ERRCODE_OFFSET(PROLOGUE)]	= "Failed to generate prologue",
1615	[ERRCODE_OFFSET(PROLOGUE2BIG)]	= "Prologue too big for program",
1616	[ERRCODE_OFFSET(PROLOGUEOOB)]	= "Offset out of bound for prologue",
1617	[ERRCODE_OFFSET(OBJCONF_OPT)]	= "Invalid object config option",
1618	[ERRCODE_OFFSET(OBJCONF_CONF)]	= "Config value not set (missing '=')",
1619	[ERRCODE_OFFSET(OBJCONF_MAP_OPT)]	= "Invalid object map config option",
1620	[ERRCODE_OFFSET(OBJCONF_MAP_NOTEXIST)]	= "Target map doesn't exist",
1621	[ERRCODE_OFFSET(OBJCONF_MAP_VALUE)]	= "Incorrect value type for map",
1622	[ERRCODE_OFFSET(OBJCONF_MAP_TYPE)]	= "Incorrect map type",
1623	[ERRCODE_OFFSET(OBJCONF_MAP_KEYSIZE)]	= "Incorrect map key size",
1624	[ERRCODE_OFFSET(OBJCONF_MAP_VALUESIZE)]	= "Incorrect map value size",
1625	[ERRCODE_OFFSET(OBJCONF_MAP_NOEVT)]	= "Event not found for map setting",
1626	[ERRCODE_OFFSET(OBJCONF_MAP_MAPSIZE)]	= "Invalid map size for event setting",
1627	[ERRCODE_OFFSET(OBJCONF_MAP_EVTDIM)]	= "Event dimension too large",
1628	[ERRCODE_OFFSET(OBJCONF_MAP_EVTINH)]	= "Doesn't support inherit event",
1629	[ERRCODE_OFFSET(OBJCONF_MAP_EVTTYPE)]	= "Wrong event type for map",
1630	[ERRCODE_OFFSET(OBJCONF_MAP_IDX2BIG)]	= "Index too large",
1631};
1632
1633static int
1634bpf_loader_strerror(int err, char *buf, size_t size)
1635{
1636	char sbuf[STRERR_BUFSIZE];
1637	const char *msg;
1638
1639	if (!buf || !size)
1640		return -1;
1641
1642	err = err > 0 ? err : -err;
1643
1644	if (err >= __LIBBPF_ERRNO__START)
1645		return libbpf_strerror(err, buf, size);
1646
1647	if (err >= __BPF_LOADER_ERRNO__START && err < __BPF_LOADER_ERRNO__END) {
1648		msg = bpf_loader_strerror_table[ERRNO_OFFSET(err)];
1649		snprintf(buf, size, "%s", msg);
1650		buf[size - 1] = '\0';
1651		return 0;
1652	}
1653
1654	if (err >= __BPF_LOADER_ERRNO__END)
1655		snprintf(buf, size, "Unknown bpf loader error %d", err);
1656	else
1657		snprintf(buf, size, "%s",
1658			 str_error_r(err, sbuf, sizeof(sbuf)));
1659
1660	buf[size - 1] = '\0';
1661	return -1;
1662}
1663
1664#define bpf__strerror_head(err, buf, size) \
1665	char sbuf[STRERR_BUFSIZE], *emsg;\
1666	if (!size)\
1667		return 0;\
1668	if (err < 0)\
1669		err = -err;\
1670	bpf_loader_strerror(err, sbuf, sizeof(sbuf));\
1671	emsg = sbuf;\
1672	switch (err) {\
1673	default:\
1674		scnprintf(buf, size, "%s", emsg);\
1675		break;
1676
1677#define bpf__strerror_entry(val, fmt...)\
1678	case val: {\
1679		scnprintf(buf, size, fmt);\
1680		break;\
1681	}
1682
1683#define bpf__strerror_end(buf, size)\
1684	}\
1685	buf[size - 1] = '\0';
1686
1687int bpf__strerror_prepare_load(const char *filename, bool source,
1688			       int err, char *buf, size_t size)
1689{
1690	size_t n;
1691	int ret;
1692
1693	n = snprintf(buf, size, "Failed to load %s%s: ",
1694			 filename, source ? " from source" : "");
1695	if (n >= size) {
1696		buf[size - 1] = '\0';
1697		return 0;
1698	}
1699	buf += n;
1700	size -= n;
1701
1702	ret = bpf_loader_strerror(err, buf, size);
1703	buf[size - 1] = '\0';
1704	return ret;
1705}
1706
1707int bpf__strerror_probe(struct bpf_object *obj __maybe_unused,
1708			int err, char *buf, size_t size)
1709{
1710	bpf__strerror_head(err, buf, size);
1711	case BPF_LOADER_ERRNO__PROGCONF_TERM: {
1712		scnprintf(buf, size, "%s (add -v to see detail)", emsg);
1713		break;
1714	}
1715	bpf__strerror_entry(EEXIST, "Probe point exist. Try 'perf probe -d \"*\"' and set 'force=yes'");
1716	bpf__strerror_entry(EACCES, "You need to be root");
1717	bpf__strerror_entry(EPERM, "You need to be root, and /proc/sys/kernel/kptr_restrict should be 0");
1718	bpf__strerror_entry(ENOENT, "You need to check probing points in BPF file");
1719	bpf__strerror_end(buf, size);
1720	return 0;
1721}
1722
1723int bpf__strerror_load(struct bpf_object *obj,
1724		       int err, char *buf, size_t size)
1725{
1726	bpf__strerror_head(err, buf, size);
1727	case LIBBPF_ERRNO__KVER: {
1728		unsigned int obj_kver = bpf_object__kversion(obj);
1729		unsigned int real_kver;
1730
1731		if (fetch_kernel_version(&real_kver, NULL, 0)) {
1732			scnprintf(buf, size, "Unable to fetch kernel version");
1733			break;
1734		}
1735
1736		if (obj_kver != real_kver) {
1737			scnprintf(buf, size,
1738				  "'version' ("KVER_FMT") doesn't match running kernel ("KVER_FMT")",
1739				  KVER_PARAM(obj_kver),
1740				  KVER_PARAM(real_kver));
1741			break;
1742		}
1743
1744		scnprintf(buf, size, "Failed to load program for unknown reason");
1745		break;
1746	}
1747	bpf__strerror_end(buf, size);
1748	return 0;
1749}
1750
1751int bpf__strerror_config_obj(struct bpf_object *obj __maybe_unused,
1752			     struct parse_events_term *term __maybe_unused,
1753			     struct perf_evlist *evlist __maybe_unused,
1754			     int *error_pos __maybe_unused, int err,
1755			     char *buf, size_t size)
1756{
1757	bpf__strerror_head(err, buf, size);
1758	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE,
1759			    "Can't use this config term with this map type");
1760	bpf__strerror_end(buf, size);
1761	return 0;
1762}
1763
1764int bpf__strerror_apply_obj_config(int err, char *buf, size_t size)
1765{
1766	bpf__strerror_head(err, buf, size);
1767	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTDIM,
1768			    "Cannot set event to BPF map in multi-thread tracing");
1769	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTINH,
1770			    "%s (Hint: use -i to turn off inherit)", emsg);
1771	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTTYPE,
1772			    "Can only put raw, hardware and BPF output event into a BPF map");
1773	bpf__strerror_end(buf, size);
1774	return 0;
1775}
1776
1777int bpf__strerror_setup_stdout(struct perf_evlist *evlist __maybe_unused,
1778			       int err, char *buf, size_t size)
1779{
1780	bpf__strerror_head(err, buf, size);
1781	bpf__strerror_end(buf, size);
1782	return 0;
1783}
v5.14.15
   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/err.h>
  13#include <linux/kernel.h>
  14#include <linux/string.h>
  15#include <linux/zalloc.h>
  16#include <errno.h>
  17#include <stdlib.h>
  18#include "debug.h"
  19#include "evlist.h"
  20#include "bpf-loader.h"
  21#include "bpf-prologue.h"
  22#include "probe-event.h"
  23#include "probe-finder.h" // for MAX_PROBES
  24#include "parse-events.h"
  25#include "strfilter.h"
  26#include "util.h"
  27#include "llvm-utils.h"
  28#include "c++/clang-c.h"
  29
  30#include <internal/xyarray.h>
 
 
 
 
 
 
 
 
 
 
  31
  32static int libbpf_perf_print(enum libbpf_print_level level __attribute__((unused)),
  33			      const char *fmt, va_list args)
  34{
  35	return veprintf(1, verbose, pr_fmt(fmt), args);
  36}
  37
  38struct bpf_prog_priv {
  39	bool is_tp;
  40	char *sys_name;
  41	char *evt_name;
  42	struct perf_probe_event pev;
  43	bool need_prologue;
  44	struct bpf_insn *insns_buf;
  45	int nr_types;
  46	int *type_mapping;
  47};
  48
  49static bool libbpf_initialized;
  50
  51struct bpf_object *
  52bpf__prepare_load_buffer(void *obj_buf, size_t obj_buf_sz, const char *name)
  53{
  54	struct bpf_object *obj;
  55
  56	if (!libbpf_initialized) {
  57		libbpf_set_print(libbpf_perf_print);
 
 
  58		libbpf_initialized = true;
  59	}
  60
  61	obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, name);
  62	if (IS_ERR_OR_NULL(obj)) {
  63		pr_debug("bpf: failed to load buffer\n");
  64		return ERR_PTR(-EINVAL);
  65	}
  66
  67	return obj;
  68}
  69
  70struct bpf_object *bpf__prepare_load(const char *filename, bool source)
  71{
  72	struct bpf_object *obj;
  73
  74	if (!libbpf_initialized) {
  75		libbpf_set_print(libbpf_perf_print);
 
 
  76		libbpf_initialized = true;
  77	}
  78
  79	if (source) {
  80		int err;
  81		void *obj_buf;
  82		size_t obj_buf_sz;
  83
  84		perf_clang__init();
  85		err = perf_clang__compile_bpf(filename, &obj_buf, &obj_buf_sz);
  86		perf_clang__cleanup();
  87		if (err) {
  88			pr_debug("bpf: builtin compilation failed: %d, try external compiler\n", err);
  89			err = llvm__compile_bpf(filename, &obj_buf, &obj_buf_sz);
  90			if (err)
  91				return ERR_PTR(-BPF_LOADER_ERRNO__COMPILE);
  92		} else
  93			pr_debug("bpf: successful builtin compilation\n");
  94		obj = bpf_object__open_buffer(obj_buf, obj_buf_sz, filename);
  95
  96		if (!IS_ERR_OR_NULL(obj) && llvm_param.dump_obj)
  97			llvm__dump_obj(filename, obj_buf, obj_buf_sz);
  98
  99		free(obj_buf);
 100	} else
 101		obj = bpf_object__open(filename);
 102
 103	if (IS_ERR_OR_NULL(obj)) {
 104		pr_debug("bpf: failed to load %s\n", filename);
 105		return obj;
 106	}
 107
 108	return obj;
 109}
 110
 111void bpf__clear(void)
 112{
 113	struct bpf_object *obj, *tmp;
 114
 115	bpf_object__for_each_safe(obj, tmp) {
 116		bpf__unprobe(obj);
 117		bpf_object__close(obj);
 118	}
 119}
 120
 121static void
 122clear_prog_priv(struct bpf_program *prog __maybe_unused,
 123		void *_priv)
 124{
 125	struct bpf_prog_priv *priv = _priv;
 126
 127	cleanup_perf_probe_events(&priv->pev, 1);
 128	zfree(&priv->insns_buf);
 129	zfree(&priv->type_mapping);
 130	zfree(&priv->sys_name);
 131	zfree(&priv->evt_name);
 132	free(priv);
 133}
 134
 135static int
 136prog_config__exec(const char *value, struct perf_probe_event *pev)
 137{
 138	pev->uprobes = true;
 139	pev->target = strdup(value);
 140	if (!pev->target)
 141		return -ENOMEM;
 142	return 0;
 143}
 144
 145static int
 146prog_config__module(const char *value, struct perf_probe_event *pev)
 147{
 148	pev->uprobes = false;
 149	pev->target = strdup(value);
 150	if (!pev->target)
 151		return -ENOMEM;
 152	return 0;
 153}
 154
 155static int
 156prog_config__bool(const char *value, bool *pbool, bool invert)
 157{
 158	int err;
 159	bool bool_value;
 160
 161	if (!pbool)
 162		return -EINVAL;
 163
 164	err = strtobool(value, &bool_value);
 165	if (err)
 166		return err;
 167
 168	*pbool = invert ? !bool_value : bool_value;
 169	return 0;
 170}
 171
 172static int
 173prog_config__inlines(const char *value,
 174		     struct perf_probe_event *pev __maybe_unused)
 175{
 176	return prog_config__bool(value, &probe_conf.no_inlines, true);
 177}
 178
 179static int
 180prog_config__force(const char *value,
 181		   struct perf_probe_event *pev __maybe_unused)
 182{
 183	return prog_config__bool(value, &probe_conf.force_add, false);
 184}
 185
 186static struct {
 187	const char *key;
 188	const char *usage;
 189	const char *desc;
 190	int (*func)(const char *, struct perf_probe_event *);
 191} bpf_prog_config_terms[] = {
 192	{
 193		.key	= "exec",
 194		.usage	= "exec=<full path of file>",
 195		.desc	= "Set uprobe target",
 196		.func	= prog_config__exec,
 197	},
 198	{
 199		.key	= "module",
 200		.usage	= "module=<module name>    ",
 201		.desc	= "Set kprobe module",
 202		.func	= prog_config__module,
 203	},
 204	{
 205		.key	= "inlines",
 206		.usage	= "inlines=[yes|no]        ",
 207		.desc	= "Probe at inline symbol",
 208		.func	= prog_config__inlines,
 209	},
 210	{
 211		.key	= "force",
 212		.usage	= "force=[yes|no]          ",
 213		.desc	= "Forcibly add events with existing name",
 214		.func	= prog_config__force,
 215	},
 216};
 217
 218static int
 219do_prog_config(const char *key, const char *value,
 220	       struct perf_probe_event *pev)
 221{
 222	unsigned int i;
 223
 224	pr_debug("config bpf program: %s=%s\n", key, value);
 225	for (i = 0; i < ARRAY_SIZE(bpf_prog_config_terms); i++)
 226		if (strcmp(key, bpf_prog_config_terms[i].key) == 0)
 227			return bpf_prog_config_terms[i].func(value, pev);
 228
 229	pr_debug("BPF: ERROR: invalid program config option: %s=%s\n",
 230		 key, value);
 231
 232	pr_debug("\nHint: Valid options are:\n");
 233	for (i = 0; i < ARRAY_SIZE(bpf_prog_config_terms); i++)
 234		pr_debug("\t%s:\t%s\n", bpf_prog_config_terms[i].usage,
 235			 bpf_prog_config_terms[i].desc);
 236	pr_debug("\n");
 237
 238	return -BPF_LOADER_ERRNO__PROGCONF_TERM;
 239}
 240
 241static const char *
 242parse_prog_config_kvpair(const char *config_str, struct perf_probe_event *pev)
 243{
 244	char *text = strdup(config_str);
 245	char *sep, *line;
 246	const char *main_str = NULL;
 247	int err = 0;
 248
 249	if (!text) {
 250		pr_debug("Not enough memory: dup config_str failed\n");
 251		return ERR_PTR(-ENOMEM);
 252	}
 253
 254	line = text;
 255	while ((sep = strchr(line, ';'))) {
 256		char *equ;
 257
 258		*sep = '\0';
 259		equ = strchr(line, '=');
 260		if (!equ) {
 261			pr_warning("WARNING: invalid config in BPF object: %s\n",
 262				   line);
 263			pr_warning("\tShould be 'key=value'.\n");
 264			goto nextline;
 265		}
 266		*equ = '\0';
 267
 268		err = do_prog_config(line, equ + 1, pev);
 269		if (err)
 270			break;
 271nextline:
 272		line = sep + 1;
 273	}
 274
 275	if (!err)
 276		main_str = config_str + (line - text);
 277	free(text);
 278
 279	return err ? ERR_PTR(err) : main_str;
 280}
 281
 282static int
 283parse_prog_config(const char *config_str, const char **p_main_str,
 284		  bool *is_tp, struct perf_probe_event *pev)
 285{
 286	int err;
 287	const char *main_str = parse_prog_config_kvpair(config_str, pev);
 288
 289	if (IS_ERR(main_str))
 290		return PTR_ERR(main_str);
 291
 292	*p_main_str = main_str;
 293	if (!strchr(main_str, '=')) {
 294		/* Is a tracepoint event? */
 295		const char *s = strchr(main_str, ':');
 296
 297		if (!s) {
 298			pr_debug("bpf: '%s' is not a valid tracepoint\n",
 299				 config_str);
 300			return -BPF_LOADER_ERRNO__CONFIG;
 301		}
 302
 303		*is_tp = true;
 304		return 0;
 305	}
 306
 307	*is_tp = false;
 308	err = parse_perf_probe_command(main_str, pev);
 309	if (err < 0) {
 310		pr_debug("bpf: '%s' is not a valid config string\n",
 311			 config_str);
 312		/* parse failed, don't need clear pev. */
 313		return -BPF_LOADER_ERRNO__CONFIG;
 314	}
 315	return 0;
 316}
 317
 318static int
 319config_bpf_program(struct bpf_program *prog)
 320{
 321	struct perf_probe_event *pev = NULL;
 322	struct bpf_prog_priv *priv = NULL;
 323	const char *config_str, *main_str;
 324	bool is_tp = false;
 325	int err;
 326
 327	/* Initialize per-program probing setting */
 328	probe_conf.no_inlines = false;
 329	probe_conf.force_add = false;
 330
 
 
 
 
 
 
 331	priv = calloc(sizeof(*priv), 1);
 332	if (!priv) {
 333		pr_debug("bpf: failed to alloc priv\n");
 334		return -ENOMEM;
 335	}
 336	pev = &priv->pev;
 337
 338	config_str = bpf_program__section_name(prog);
 339	pr_debug("bpf: config program '%s'\n", config_str);
 340	err = parse_prog_config(config_str, &main_str, &is_tp, pev);
 341	if (err)
 342		goto errout;
 343
 344	if (is_tp) {
 345		char *s = strchr(main_str, ':');
 346
 347		priv->is_tp = true;
 348		priv->sys_name = strndup(main_str, s - main_str);
 349		priv->evt_name = strdup(s + 1);
 350		goto set_priv;
 351	}
 352
 353	if (pev->group && strcmp(pev->group, PERF_BPF_PROBE_GROUP)) {
 354		pr_debug("bpf: '%s': group for event is set and not '%s'.\n",
 355			 config_str, PERF_BPF_PROBE_GROUP);
 356		err = -BPF_LOADER_ERRNO__GROUP;
 357		goto errout;
 358	} else if (!pev->group)
 359		pev->group = strdup(PERF_BPF_PROBE_GROUP);
 360
 361	if (!pev->group) {
 362		pr_debug("bpf: strdup failed\n");
 363		err = -ENOMEM;
 364		goto errout;
 365	}
 366
 367	if (!pev->event) {
 368		pr_debug("bpf: '%s': event name is missing. Section name should be 'key=value'\n",
 369			 config_str);
 370		err = -BPF_LOADER_ERRNO__EVENTNAME;
 371		goto errout;
 372	}
 373	pr_debug("bpf: config '%s' is ok\n", config_str);
 374
 375set_priv:
 376	err = bpf_program__set_priv(prog, priv, clear_prog_priv);
 377	if (err) {
 378		pr_debug("Failed to set priv for program '%s'\n", config_str);
 379		goto errout;
 380	}
 381
 382	return 0;
 383
 384errout:
 385	if (pev)
 386		clear_perf_probe_event(pev);
 387	free(priv);
 388	return err;
 389}
 390
 391static int bpf__prepare_probe(void)
 392{
 393	static int err = 0;
 394	static bool initialized = false;
 395
 396	/*
 397	 * Make err static, so if init failed the first, bpf__prepare_probe()
 398	 * fails each time without calling init_probe_symbol_maps multiple
 399	 * times.
 400	 */
 401	if (initialized)
 402		return err;
 403
 404	initialized = true;
 405	err = init_probe_symbol_maps(false);
 406	if (err < 0)
 407		pr_debug("Failed to init_probe_symbol_maps\n");
 408	probe_conf.max_probes = MAX_PROBES;
 409	return err;
 410}
 411
 412static int
 413preproc_gen_prologue(struct bpf_program *prog, int n,
 414		     struct bpf_insn *orig_insns, int orig_insns_cnt,
 415		     struct bpf_prog_prep_result *res)
 416{
 417	struct bpf_prog_priv *priv = bpf_program__priv(prog);
 418	struct probe_trace_event *tev;
 419	struct perf_probe_event *pev;
 420	struct bpf_insn *buf;
 421	size_t prologue_cnt = 0;
 422	int i, err;
 423
 424	if (IS_ERR(priv) || !priv || priv->is_tp)
 425		goto errout;
 426
 427	pev = &priv->pev;
 428
 429	if (n < 0 || n >= priv->nr_types)
 430		goto errout;
 431
 432	/* Find a tev belongs to that type */
 433	for (i = 0; i < pev->ntevs; i++) {
 434		if (priv->type_mapping[i] == n)
 435			break;
 436	}
 437
 438	if (i >= pev->ntevs) {
 439		pr_debug("Internal error: prologue type %d not found\n", n);
 440		return -BPF_LOADER_ERRNO__PROLOGUE;
 441	}
 442
 443	tev = &pev->tevs[i];
 444
 445	buf = priv->insns_buf;
 446	err = bpf__gen_prologue(tev->args, tev->nargs,
 447				buf, &prologue_cnt,
 448				BPF_MAXINSNS - orig_insns_cnt);
 449	if (err) {
 450		const char *title;
 451
 452		title = bpf_program__section_name(prog);
 
 
 
 453		pr_debug("Failed to generate prologue for program %s\n",
 454			 title);
 455		return err;
 456	}
 457
 458	memcpy(&buf[prologue_cnt], orig_insns,
 459	       sizeof(struct bpf_insn) * orig_insns_cnt);
 460
 461	res->new_insn_ptr = buf;
 462	res->new_insn_cnt = prologue_cnt + orig_insns_cnt;
 463	res->pfd = NULL;
 464	return 0;
 465
 466errout:
 467	pr_debug("Internal error in preproc_gen_prologue\n");
 468	return -BPF_LOADER_ERRNO__PROLOGUE;
 469}
 470
 471/*
 472 * compare_tev_args is reflexive, transitive and antisymmetric.
 473 * I can proof it but this margin is too narrow to contain.
 474 */
 475static int compare_tev_args(const void *ptev1, const void *ptev2)
 476{
 477	int i, ret;
 478	const struct probe_trace_event *tev1 =
 479		*(const struct probe_trace_event **)ptev1;
 480	const struct probe_trace_event *tev2 =
 481		*(const struct probe_trace_event **)ptev2;
 482
 483	ret = tev2->nargs - tev1->nargs;
 484	if (ret)
 485		return ret;
 486
 487	for (i = 0; i < tev1->nargs; i++) {
 488		struct probe_trace_arg *arg1, *arg2;
 489		struct probe_trace_arg_ref *ref1, *ref2;
 490
 491		arg1 = &tev1->args[i];
 492		arg2 = &tev2->args[i];
 493
 494		ret = strcmp(arg1->value, arg2->value);
 495		if (ret)
 496			return ret;
 497
 498		ref1 = arg1->ref;
 499		ref2 = arg2->ref;
 500
 501		while (ref1 && ref2) {
 502			ret = ref2->offset - ref1->offset;
 503			if (ret)
 504				return ret;
 505
 506			ref1 = ref1->next;
 507			ref2 = ref2->next;
 508		}
 509
 510		if (ref1 || ref2)
 511			return ref2 ? 1 : -1;
 512	}
 513
 514	return 0;
 515}
 516
 517/*
 518 * Assign a type number to each tevs in a pev.
 519 * mapping is an array with same slots as tevs in that pev.
 520 * nr_types will be set to number of types.
 521 */
 522static int map_prologue(struct perf_probe_event *pev, int *mapping,
 523			int *nr_types)
 524{
 525	int i, type = 0;
 526	struct probe_trace_event **ptevs;
 527
 528	size_t array_sz = sizeof(*ptevs) * pev->ntevs;
 529
 530	ptevs = malloc(array_sz);
 531	if (!ptevs) {
 532		pr_debug("Not enough memory: alloc ptevs failed\n");
 533		return -ENOMEM;
 534	}
 535
 536	pr_debug("In map_prologue, ntevs=%d\n", pev->ntevs);
 537	for (i = 0; i < pev->ntevs; i++)
 538		ptevs[i] = &pev->tevs[i];
 539
 540	qsort(ptevs, pev->ntevs, sizeof(*ptevs),
 541	      compare_tev_args);
 542
 543	for (i = 0; i < pev->ntevs; i++) {
 544		int n;
 545
 546		n = ptevs[i] - pev->tevs;
 547		if (i == 0) {
 548			mapping[n] = type;
 549			pr_debug("mapping[%d]=%d\n", n, type);
 550			continue;
 551		}
 552
 553		if (compare_tev_args(ptevs + i, ptevs + i - 1) == 0)
 554			mapping[n] = type;
 555		else
 556			mapping[n] = ++type;
 557
 558		pr_debug("mapping[%d]=%d\n", n, mapping[n]);
 559	}
 560	free(ptevs);
 561	*nr_types = type + 1;
 562
 563	return 0;
 564}
 565
 566static int hook_load_preprocessor(struct bpf_program *prog)
 567{
 568	struct bpf_prog_priv *priv = bpf_program__priv(prog);
 569	struct perf_probe_event *pev;
 570	bool need_prologue = false;
 571	int err, i;
 572
 573	if (IS_ERR(priv) || !priv) {
 574		pr_debug("Internal error when hook preprocessor\n");
 575		return -BPF_LOADER_ERRNO__INTERNAL;
 576	}
 577
 578	if (priv->is_tp) {
 579		priv->need_prologue = false;
 580		return 0;
 581	}
 582
 583	pev = &priv->pev;
 584	for (i = 0; i < pev->ntevs; i++) {
 585		struct probe_trace_event *tev = &pev->tevs[i];
 586
 587		if (tev->nargs > 0) {
 588			need_prologue = true;
 589			break;
 590		}
 591	}
 592
 593	/*
 594	 * Since all tevs don't have argument, we don't need generate
 595	 * prologue.
 596	 */
 597	if (!need_prologue) {
 598		priv->need_prologue = false;
 599		return 0;
 600	}
 601
 602	priv->need_prologue = true;
 603	priv->insns_buf = malloc(sizeof(struct bpf_insn) * BPF_MAXINSNS);
 604	if (!priv->insns_buf) {
 605		pr_debug("Not enough memory: alloc insns_buf failed\n");
 606		return -ENOMEM;
 607	}
 608
 609	priv->type_mapping = malloc(sizeof(int) * pev->ntevs);
 610	if (!priv->type_mapping) {
 611		pr_debug("Not enough memory: alloc type_mapping failed\n");
 612		return -ENOMEM;
 613	}
 614	memset(priv->type_mapping, -1,
 615	       sizeof(int) * pev->ntevs);
 616
 617	err = map_prologue(pev, priv->type_mapping, &priv->nr_types);
 618	if (err)
 619		return err;
 620
 621	err = bpf_program__set_prep(prog, priv->nr_types,
 622				    preproc_gen_prologue);
 623	return err;
 624}
 625
 626int bpf__probe(struct bpf_object *obj)
 627{
 628	int err = 0;
 629	struct bpf_program *prog;
 630	struct bpf_prog_priv *priv;
 631	struct perf_probe_event *pev;
 632
 633	err = bpf__prepare_probe();
 634	if (err) {
 635		pr_debug("bpf__prepare_probe failed\n");
 636		return err;
 637	}
 638
 639	bpf_object__for_each_program(prog, obj) {
 640		err = config_bpf_program(prog);
 641		if (err)
 642			goto out;
 643
 644		priv = bpf_program__priv(prog);
 645		if (IS_ERR(priv) || !priv) {
 646			err = PTR_ERR(priv);
 647			goto out;
 648		}
 649
 650		if (priv->is_tp) {
 651			bpf_program__set_tracepoint(prog);
 652			continue;
 653		}
 654
 655		bpf_program__set_kprobe(prog);
 656		pev = &priv->pev;
 657
 658		err = convert_perf_probe_events(pev, 1);
 659		if (err < 0) {
 660			pr_debug("bpf_probe: failed to convert perf probe events\n");
 661			goto out;
 662		}
 663
 664		err = apply_perf_probe_events(pev, 1);
 665		if (err < 0) {
 666			pr_debug("bpf_probe: failed to apply perf probe events\n");
 667			goto out;
 668		}
 669
 670		/*
 671		 * After probing, let's consider prologue, which
 672		 * adds program fetcher to BPF programs.
 673		 *
 674		 * hook_load_preprocessor() hooks pre-processor
 675		 * to bpf_program, let it generate prologue
 676		 * dynamically during loading.
 677		 */
 678		err = hook_load_preprocessor(prog);
 679		if (err)
 680			goto out;
 681	}
 682out:
 683	return err < 0 ? err : 0;
 684}
 685
 686#define EVENTS_WRITE_BUFSIZE  4096
 687int bpf__unprobe(struct bpf_object *obj)
 688{
 689	int err, ret = 0;
 690	struct bpf_program *prog;
 691
 692	bpf_object__for_each_program(prog, obj) {
 693		struct bpf_prog_priv *priv = bpf_program__priv(prog);
 694		int i;
 695
 696		if (IS_ERR(priv) || !priv || priv->is_tp)
 697			continue;
 698
 699		for (i = 0; i < priv->pev.ntevs; i++) {
 700			struct probe_trace_event *tev = &priv->pev.tevs[i];
 701			char name_buf[EVENTS_WRITE_BUFSIZE];
 702			struct strfilter *delfilter;
 703
 704			snprintf(name_buf, EVENTS_WRITE_BUFSIZE,
 705				 "%s:%s", tev->group, tev->event);
 706			name_buf[EVENTS_WRITE_BUFSIZE - 1] = '\0';
 707
 708			delfilter = strfilter__new(name_buf, NULL);
 709			if (!delfilter) {
 710				pr_debug("Failed to create filter for unprobing\n");
 711				ret = -ENOMEM;
 712				continue;
 713			}
 714
 715			err = del_perf_probe_events(delfilter);
 716			strfilter__delete(delfilter);
 717			if (err) {
 718				pr_debug("Failed to delete %s\n", name_buf);
 719				ret = err;
 720				continue;
 721			}
 722		}
 723	}
 724	return ret;
 725}
 726
 727int bpf__load(struct bpf_object *obj)
 728{
 729	int err;
 730
 731	err = bpf_object__load(obj);
 732	if (err) {
 733		char bf[128];
 734		libbpf_strerror(err, bf, sizeof(bf));
 735		pr_debug("bpf: load objects failed: err=%d: (%s)\n", err, bf);
 736		return err;
 737	}
 738	return 0;
 739}
 740
 741int bpf__foreach_event(struct bpf_object *obj,
 742		       bpf_prog_iter_callback_t func,
 743		       void *arg)
 744{
 745	struct bpf_program *prog;
 746	int err;
 747
 748	bpf_object__for_each_program(prog, obj) {
 749		struct bpf_prog_priv *priv = bpf_program__priv(prog);
 750		struct probe_trace_event *tev;
 751		struct perf_probe_event *pev;
 752		int i, fd;
 753
 754		if (IS_ERR(priv) || !priv) {
 755			pr_debug("bpf: failed to get private field\n");
 756			return -BPF_LOADER_ERRNO__INTERNAL;
 757		}
 758
 759		if (priv->is_tp) {
 760			fd = bpf_program__fd(prog);
 761			err = (*func)(priv->sys_name, priv->evt_name, fd, obj, arg);
 762			if (err) {
 763				pr_debug("bpf: tracepoint call back failed, stop iterate\n");
 764				return err;
 765			}
 766			continue;
 767		}
 768
 769		pev = &priv->pev;
 770		for (i = 0; i < pev->ntevs; i++) {
 771			tev = &pev->tevs[i];
 772
 773			if (priv->need_prologue) {
 774				int type = priv->type_mapping[i];
 775
 776				fd = bpf_program__nth_fd(prog, type);
 777			} else {
 778				fd = bpf_program__fd(prog);
 779			}
 780
 781			if (fd < 0) {
 782				pr_debug("bpf: failed to get file descriptor\n");
 783				return fd;
 784			}
 785
 786			err = (*func)(tev->group, tev->event, fd, obj, arg);
 787			if (err) {
 788				pr_debug("bpf: call back failed, stop iterate\n");
 789				return err;
 790			}
 791		}
 792	}
 793	return 0;
 794}
 795
 796enum bpf_map_op_type {
 797	BPF_MAP_OP_SET_VALUE,
 798	BPF_MAP_OP_SET_EVSEL,
 799};
 800
 801enum bpf_map_key_type {
 802	BPF_MAP_KEY_ALL,
 803	BPF_MAP_KEY_RANGES,
 804};
 805
 806struct bpf_map_op {
 807	struct list_head list;
 808	enum bpf_map_op_type op_type;
 809	enum bpf_map_key_type key_type;
 810	union {
 811		struct parse_events_array array;
 812	} k;
 813	union {
 814		u64 value;
 815		struct evsel *evsel;
 816	} v;
 817};
 818
 819struct bpf_map_priv {
 820	struct list_head ops_list;
 821};
 822
 823static void
 824bpf_map_op__delete(struct bpf_map_op *op)
 825{
 826	if (!list_empty(&op->list))
 827		list_del_init(&op->list);
 828	if (op->key_type == BPF_MAP_KEY_RANGES)
 829		parse_events__clear_array(&op->k.array);
 830	free(op);
 831}
 832
 833static void
 834bpf_map_priv__purge(struct bpf_map_priv *priv)
 835{
 836	struct bpf_map_op *pos, *n;
 837
 838	list_for_each_entry_safe(pos, n, &priv->ops_list, list) {
 839		list_del_init(&pos->list);
 840		bpf_map_op__delete(pos);
 841	}
 842}
 843
 844static void
 845bpf_map_priv__clear(struct bpf_map *map __maybe_unused,
 846		    void *_priv)
 847{
 848	struct bpf_map_priv *priv = _priv;
 849
 850	bpf_map_priv__purge(priv);
 851	free(priv);
 852}
 853
 854static int
 855bpf_map_op_setkey(struct bpf_map_op *op, struct parse_events_term *term)
 856{
 857	op->key_type = BPF_MAP_KEY_ALL;
 858	if (!term)
 859		return 0;
 860
 861	if (term->array.nr_ranges) {
 862		size_t memsz = term->array.nr_ranges *
 863				sizeof(op->k.array.ranges[0]);
 864
 865		op->k.array.ranges = memdup(term->array.ranges, memsz);
 866		if (!op->k.array.ranges) {
 867			pr_debug("Not enough memory to alloc indices for map\n");
 868			return -ENOMEM;
 869		}
 870		op->key_type = BPF_MAP_KEY_RANGES;
 871		op->k.array.nr_ranges = term->array.nr_ranges;
 872	}
 873	return 0;
 874}
 875
 876static struct bpf_map_op *
 877bpf_map_op__new(struct parse_events_term *term)
 878{
 879	struct bpf_map_op *op;
 880	int err;
 881
 882	op = zalloc(sizeof(*op));
 883	if (!op) {
 884		pr_debug("Failed to alloc bpf_map_op\n");
 885		return ERR_PTR(-ENOMEM);
 886	}
 887	INIT_LIST_HEAD(&op->list);
 888
 889	err = bpf_map_op_setkey(op, term);
 890	if (err) {
 891		free(op);
 892		return ERR_PTR(err);
 893	}
 894	return op;
 895}
 896
 897static struct bpf_map_op *
 898bpf_map_op__clone(struct bpf_map_op *op)
 899{
 900	struct bpf_map_op *newop;
 901
 902	newop = memdup(op, sizeof(*op));
 903	if (!newop) {
 904		pr_debug("Failed to alloc bpf_map_op\n");
 905		return NULL;
 906	}
 907
 908	INIT_LIST_HEAD(&newop->list);
 909	if (op->key_type == BPF_MAP_KEY_RANGES) {
 910		size_t memsz = op->k.array.nr_ranges *
 911			       sizeof(op->k.array.ranges[0]);
 912
 913		newop->k.array.ranges = memdup(op->k.array.ranges, memsz);
 914		if (!newop->k.array.ranges) {
 915			pr_debug("Failed to alloc indices for map\n");
 916			free(newop);
 917			return NULL;
 918		}
 919	}
 920
 921	return newop;
 922}
 923
 924static struct bpf_map_priv *
 925bpf_map_priv__clone(struct bpf_map_priv *priv)
 926{
 927	struct bpf_map_priv *newpriv;
 928	struct bpf_map_op *pos, *newop;
 929
 930	newpriv = zalloc(sizeof(*newpriv));
 931	if (!newpriv) {
 932		pr_debug("Not enough memory to alloc map private\n");
 933		return NULL;
 934	}
 935	INIT_LIST_HEAD(&newpriv->ops_list);
 936
 937	list_for_each_entry(pos, &priv->ops_list, list) {
 938		newop = bpf_map_op__clone(pos);
 939		if (!newop) {
 940			bpf_map_priv__purge(newpriv);
 941			return NULL;
 942		}
 943		list_add_tail(&newop->list, &newpriv->ops_list);
 944	}
 945
 946	return newpriv;
 947}
 948
 949static int
 950bpf_map__add_op(struct bpf_map *map, struct bpf_map_op *op)
 951{
 952	const char *map_name = bpf_map__name(map);
 953	struct bpf_map_priv *priv = bpf_map__priv(map);
 954
 955	if (IS_ERR(priv)) {
 956		pr_debug("Failed to get private from map %s\n", map_name);
 957		return PTR_ERR(priv);
 958	}
 959
 960	if (!priv) {
 961		priv = zalloc(sizeof(*priv));
 962		if (!priv) {
 963			pr_debug("Not enough memory to alloc map private\n");
 964			return -ENOMEM;
 965		}
 966		INIT_LIST_HEAD(&priv->ops_list);
 967
 968		if (bpf_map__set_priv(map, priv, bpf_map_priv__clear)) {
 969			free(priv);
 970			return -BPF_LOADER_ERRNO__INTERNAL;
 971		}
 972	}
 973
 974	list_add_tail(&op->list, &priv->ops_list);
 975	return 0;
 976}
 977
 978static struct bpf_map_op *
 979bpf_map__add_newop(struct bpf_map *map, struct parse_events_term *term)
 980{
 981	struct bpf_map_op *op;
 982	int err;
 983
 984	op = bpf_map_op__new(term);
 985	if (IS_ERR(op))
 986		return op;
 987
 988	err = bpf_map__add_op(map, op);
 989	if (err) {
 990		bpf_map_op__delete(op);
 991		return ERR_PTR(err);
 992	}
 993	return op;
 994}
 995
 996static int
 997__bpf_map__config_value(struct bpf_map *map,
 998			struct parse_events_term *term)
 999{
1000	struct bpf_map_op *op;
1001	const char *map_name = bpf_map__name(map);
1002	const struct bpf_map_def *def = bpf_map__def(map);
1003
1004	if (IS_ERR(def)) {
1005		pr_debug("Unable to get map definition from '%s'\n",
1006			 map_name);
1007		return -BPF_LOADER_ERRNO__INTERNAL;
1008	}
1009
1010	if (def->type != BPF_MAP_TYPE_ARRAY) {
1011		pr_debug("Map %s type is not BPF_MAP_TYPE_ARRAY\n",
1012			 map_name);
1013		return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1014	}
1015	if (def->key_size < sizeof(unsigned int)) {
1016		pr_debug("Map %s has incorrect key size\n", map_name);
1017		return -BPF_LOADER_ERRNO__OBJCONF_MAP_KEYSIZE;
1018	}
1019	switch (def->value_size) {
1020	case 1:
1021	case 2:
1022	case 4:
1023	case 8:
1024		break;
1025	default:
1026		pr_debug("Map %s has incorrect value size\n", map_name);
1027		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE;
1028	}
1029
1030	op = bpf_map__add_newop(map, term);
1031	if (IS_ERR(op))
1032		return PTR_ERR(op);
1033	op->op_type = BPF_MAP_OP_SET_VALUE;
1034	op->v.value = term->val.num;
1035	return 0;
1036}
1037
1038static int
1039bpf_map__config_value(struct bpf_map *map,
1040		      struct parse_events_term *term,
1041		      struct evlist *evlist __maybe_unused)
1042{
1043	if (!term->err_val) {
1044		pr_debug("Config value not set\n");
1045		return -BPF_LOADER_ERRNO__OBJCONF_CONF;
1046	}
1047
1048	if (term->type_val != PARSE_EVENTS__TERM_TYPE_NUM) {
1049		pr_debug("ERROR: wrong value type for 'value'\n");
1050		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE;
1051	}
1052
1053	return __bpf_map__config_value(map, term);
1054}
1055
1056static int
1057__bpf_map__config_event(struct bpf_map *map,
1058			struct parse_events_term *term,
1059			struct evlist *evlist)
1060{
 
1061	const struct bpf_map_def *def;
1062	struct bpf_map_op *op;
1063	const char *map_name = bpf_map__name(map);
1064	struct evsel *evsel = evlist__find_evsel_by_str(evlist, term->val.str);
1065
 
1066	if (!evsel) {
1067		pr_debug("Event (for '%s') '%s' doesn't exist\n",
1068			 map_name, term->val.str);
1069		return -BPF_LOADER_ERRNO__OBJCONF_MAP_NOEVT;
1070	}
1071
1072	def = bpf_map__def(map);
1073	if (IS_ERR(def)) {
1074		pr_debug("Unable to get map definition from '%s'\n",
1075			 map_name);
1076		return PTR_ERR(def);
1077	}
1078
1079	/*
1080	 * No need to check key_size and value_size:
1081	 * kernel has already checked them.
1082	 */
1083	if (def->type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) {
1084		pr_debug("Map %s type is not BPF_MAP_TYPE_PERF_EVENT_ARRAY\n",
1085			 map_name);
1086		return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1087	}
1088
1089	op = bpf_map__add_newop(map, term);
1090	if (IS_ERR(op))
1091		return PTR_ERR(op);
1092	op->op_type = BPF_MAP_OP_SET_EVSEL;
1093	op->v.evsel = evsel;
1094	return 0;
1095}
1096
1097static int
1098bpf_map__config_event(struct bpf_map *map,
1099		      struct parse_events_term *term,
1100		      struct evlist *evlist)
1101{
1102	if (!term->err_val) {
1103		pr_debug("Config value not set\n");
1104		return -BPF_LOADER_ERRNO__OBJCONF_CONF;
1105	}
1106
1107	if (term->type_val != PARSE_EVENTS__TERM_TYPE_STR) {
1108		pr_debug("ERROR: wrong value type for 'event'\n");
1109		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE;
1110	}
1111
1112	return __bpf_map__config_event(map, term, evlist);
1113}
1114
1115struct bpf_obj_config__map_func {
1116	const char *config_opt;
1117	int (*config_func)(struct bpf_map *, struct parse_events_term *,
1118			   struct evlist *);
1119};
1120
1121struct bpf_obj_config__map_func bpf_obj_config__map_funcs[] = {
1122	{"value", bpf_map__config_value},
1123	{"event", bpf_map__config_event},
1124};
1125
1126static int
1127config_map_indices_range_check(struct parse_events_term *term,
1128			       struct bpf_map *map,
1129			       const char *map_name)
1130{
1131	struct parse_events_array *array = &term->array;
1132	const struct bpf_map_def *def;
1133	unsigned int i;
1134
1135	if (!array->nr_ranges)
1136		return 0;
1137	if (!array->ranges) {
1138		pr_debug("ERROR: map %s: array->nr_ranges is %d but range array is NULL\n",
1139			 map_name, (int)array->nr_ranges);
1140		return -BPF_LOADER_ERRNO__INTERNAL;
1141	}
1142
1143	def = bpf_map__def(map);
1144	if (IS_ERR(def)) {
1145		pr_debug("ERROR: Unable to get map definition from '%s'\n",
1146			 map_name);
1147		return -BPF_LOADER_ERRNO__INTERNAL;
1148	}
1149
1150	for (i = 0; i < array->nr_ranges; i++) {
1151		unsigned int start = array->ranges[i].start;
1152		size_t length = array->ranges[i].length;
1153		unsigned int idx = start + length - 1;
1154
1155		if (idx >= def->max_entries) {
1156			pr_debug("ERROR: index %d too large\n", idx);
1157			return -BPF_LOADER_ERRNO__OBJCONF_MAP_IDX2BIG;
1158		}
1159	}
1160	return 0;
1161}
1162
1163static int
1164bpf__obj_config_map(struct bpf_object *obj,
1165		    struct parse_events_term *term,
1166		    struct evlist *evlist,
1167		    int *key_scan_pos)
1168{
1169	/* key is "map:<mapname>.<config opt>" */
1170	char *map_name = strdup(term->config + sizeof("map:") - 1);
1171	struct bpf_map *map;
1172	int err = -BPF_LOADER_ERRNO__OBJCONF_OPT;
1173	char *map_opt;
1174	size_t i;
1175
1176	if (!map_name)
1177		return -ENOMEM;
1178
1179	map_opt = strchr(map_name, '.');
1180	if (!map_opt) {
1181		pr_debug("ERROR: Invalid map config: %s\n", map_name);
1182		goto out;
1183	}
1184
1185	*map_opt++ = '\0';
1186	if (*map_opt == '\0') {
1187		pr_debug("ERROR: Invalid map option: %s\n", term->config);
1188		goto out;
1189	}
1190
1191	map = bpf_object__find_map_by_name(obj, map_name);
1192	if (!map) {
1193		pr_debug("ERROR: Map %s doesn't exist\n", map_name);
1194		err = -BPF_LOADER_ERRNO__OBJCONF_MAP_NOTEXIST;
1195		goto out;
1196	}
1197
1198	*key_scan_pos += strlen(map_opt);
1199	err = config_map_indices_range_check(term, map, map_name);
1200	if (err)
1201		goto out;
1202	*key_scan_pos -= strlen(map_opt);
1203
1204	for (i = 0; i < ARRAY_SIZE(bpf_obj_config__map_funcs); i++) {
1205		struct bpf_obj_config__map_func *func =
1206				&bpf_obj_config__map_funcs[i];
1207
1208		if (strcmp(map_opt, func->config_opt) == 0) {
1209			err = func->config_func(map, term, evlist);
1210			goto out;
1211		}
1212	}
1213
1214	pr_debug("ERROR: Invalid map config option '%s'\n", map_opt);
1215	err = -BPF_LOADER_ERRNO__OBJCONF_MAP_OPT;
1216out:
1217	free(map_name);
1218	if (!err)
1219		*key_scan_pos += strlen(map_opt);
1220	return err;
1221}
1222
1223int bpf__config_obj(struct bpf_object *obj,
1224		    struct parse_events_term *term,
1225		    struct evlist *evlist,
1226		    int *error_pos)
1227{
1228	int key_scan_pos = 0;
1229	int err;
1230
1231	if (!obj || !term || !term->config)
1232		return -EINVAL;
1233
1234	if (strstarts(term->config, "map:")) {
1235		key_scan_pos = sizeof("map:") - 1;
1236		err = bpf__obj_config_map(obj, term, evlist, &key_scan_pos);
1237		goto out;
1238	}
1239	err = -BPF_LOADER_ERRNO__OBJCONF_OPT;
1240out:
1241	if (error_pos)
1242		*error_pos = key_scan_pos;
1243	return err;
1244
1245}
1246
1247typedef int (*map_config_func_t)(const char *name, int map_fd,
1248				 const struct bpf_map_def *pdef,
1249				 struct bpf_map_op *op,
1250				 void *pkey, void *arg);
1251
1252static int
1253foreach_key_array_all(map_config_func_t func,
1254		      void *arg, const char *name,
1255		      int map_fd, const struct bpf_map_def *pdef,
1256		      struct bpf_map_op *op)
1257{
1258	unsigned int i;
1259	int err;
1260
1261	for (i = 0; i < pdef->max_entries; i++) {
1262		err = func(name, map_fd, pdef, op, &i, arg);
1263		if (err) {
1264			pr_debug("ERROR: failed to insert value to %s[%u]\n",
1265				 name, i);
1266			return err;
1267		}
1268	}
1269	return 0;
1270}
1271
1272static int
1273foreach_key_array_ranges(map_config_func_t func, void *arg,
1274			 const char *name, int map_fd,
1275			 const struct bpf_map_def *pdef,
1276			 struct bpf_map_op *op)
1277{
1278	unsigned int i, j;
1279	int err;
1280
1281	for (i = 0; i < op->k.array.nr_ranges; i++) {
1282		unsigned int start = op->k.array.ranges[i].start;
1283		size_t length = op->k.array.ranges[i].length;
1284
1285		for (j = 0; j < length; j++) {
1286			unsigned int idx = start + j;
1287
1288			err = func(name, map_fd, pdef, op, &idx, arg);
1289			if (err) {
1290				pr_debug("ERROR: failed to insert value to %s[%u]\n",
1291					 name, idx);
1292				return err;
1293			}
1294		}
1295	}
1296	return 0;
1297}
1298
1299static int
1300bpf_map_config_foreach_key(struct bpf_map *map,
1301			   map_config_func_t func,
1302			   void *arg)
1303{
1304	int err, map_fd;
1305	struct bpf_map_op *op;
1306	const struct bpf_map_def *def;
1307	const char *name = bpf_map__name(map);
1308	struct bpf_map_priv *priv = bpf_map__priv(map);
1309
1310	if (IS_ERR(priv)) {
1311		pr_debug("ERROR: failed to get private from map %s\n", name);
1312		return -BPF_LOADER_ERRNO__INTERNAL;
1313	}
1314	if (!priv || list_empty(&priv->ops_list)) {
1315		pr_debug("INFO: nothing to config for map %s\n", name);
1316		return 0;
1317	}
1318
1319	def = bpf_map__def(map);
1320	if (IS_ERR(def)) {
1321		pr_debug("ERROR: failed to get definition from map %s\n", name);
1322		return -BPF_LOADER_ERRNO__INTERNAL;
1323	}
1324	map_fd = bpf_map__fd(map);
1325	if (map_fd < 0) {
1326		pr_debug("ERROR: failed to get fd from map %s\n", name);
1327		return map_fd;
1328	}
1329
1330	list_for_each_entry(op, &priv->ops_list, list) {
1331		switch (def->type) {
1332		case BPF_MAP_TYPE_ARRAY:
1333		case BPF_MAP_TYPE_PERF_EVENT_ARRAY:
1334			switch (op->key_type) {
1335			case BPF_MAP_KEY_ALL:
1336				err = foreach_key_array_all(func, arg, name,
1337							    map_fd, def, op);
1338				break;
1339			case BPF_MAP_KEY_RANGES:
1340				err = foreach_key_array_ranges(func, arg, name,
1341							       map_fd, def,
1342							       op);
1343				break;
1344			default:
1345				pr_debug("ERROR: keytype for map '%s' invalid\n",
1346					 name);
1347				return -BPF_LOADER_ERRNO__INTERNAL;
1348			}
1349			if (err)
1350				return err;
1351			break;
1352		default:
1353			pr_debug("ERROR: type of '%s' incorrect\n", name);
1354			return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE;
1355		}
1356	}
1357
1358	return 0;
1359}
1360
1361static int
1362apply_config_value_for_key(int map_fd, void *pkey,
1363			   size_t val_size, u64 val)
1364{
1365	int err = 0;
1366
1367	switch (val_size) {
1368	case 1: {
1369		u8 _val = (u8)(val);
1370		err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1371		break;
1372	}
1373	case 2: {
1374		u16 _val = (u16)(val);
1375		err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1376		break;
1377	}
1378	case 4: {
1379		u32 _val = (u32)(val);
1380		err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY);
1381		break;
1382	}
1383	case 8: {
1384		err = bpf_map_update_elem(map_fd, pkey, &val, BPF_ANY);
1385		break;
1386	}
1387	default:
1388		pr_debug("ERROR: invalid value size\n");
1389		return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE;
1390	}
1391	if (err && errno)
1392		err = -errno;
1393	return err;
1394}
1395
1396static int
1397apply_config_evsel_for_key(const char *name, int map_fd, void *pkey,
1398			   struct evsel *evsel)
1399{
1400	struct xyarray *xy = evsel->core.fd;
1401	struct perf_event_attr *attr;
1402	unsigned int key, events;
1403	bool check_pass = false;
1404	int *evt_fd;
1405	int err;
1406
1407	if (!xy) {
1408		pr_debug("ERROR: evsel not ready for map %s\n", name);
1409		return -BPF_LOADER_ERRNO__INTERNAL;
1410	}
1411
1412	if (xy->row_size / xy->entry_size != 1) {
1413		pr_debug("ERROR: Dimension of target event is incorrect for map %s\n",
1414			 name);
1415		return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTDIM;
1416	}
1417
1418	attr = &evsel->core.attr;
1419	if (attr->inherit) {
1420		pr_debug("ERROR: Can't put inherit event into map %s\n", name);
1421		return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTINH;
1422	}
1423
1424	if (evsel__is_bpf_output(evsel))
1425		check_pass = true;
1426	if (attr->type == PERF_TYPE_RAW)
1427		check_pass = true;
1428	if (attr->type == PERF_TYPE_HARDWARE)
1429		check_pass = true;
1430	if (!check_pass) {
1431		pr_debug("ERROR: Event type is wrong for map %s\n", name);
1432		return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTTYPE;
1433	}
1434
1435	events = xy->entries / (xy->row_size / xy->entry_size);
1436	key = *((unsigned int *)pkey);
1437	if (key >= events) {
1438		pr_debug("ERROR: there is no event %d for map %s\n",
1439			 key, name);
1440		return -BPF_LOADER_ERRNO__OBJCONF_MAP_MAPSIZE;
1441	}
1442	evt_fd = xyarray__entry(xy, key, 0);
1443	err = bpf_map_update_elem(map_fd, pkey, evt_fd, BPF_ANY);
1444	if (err && errno)
1445		err = -errno;
1446	return err;
1447}
1448
1449static int
1450apply_obj_config_map_for_key(const char *name, int map_fd,
1451			     const struct bpf_map_def *pdef,
1452			     struct bpf_map_op *op,
1453			     void *pkey, void *arg __maybe_unused)
1454{
1455	int err;
1456
1457	switch (op->op_type) {
1458	case BPF_MAP_OP_SET_VALUE:
1459		err = apply_config_value_for_key(map_fd, pkey,
1460						 pdef->value_size,
1461						 op->v.value);
1462		break;
1463	case BPF_MAP_OP_SET_EVSEL:
1464		err = apply_config_evsel_for_key(name, map_fd, pkey,
1465						 op->v.evsel);
1466		break;
1467	default:
1468		pr_debug("ERROR: unknown value type for '%s'\n", name);
1469		err = -BPF_LOADER_ERRNO__INTERNAL;
1470	}
1471	return err;
1472}
1473
1474static int
1475apply_obj_config_map(struct bpf_map *map)
1476{
1477	return bpf_map_config_foreach_key(map,
1478					  apply_obj_config_map_for_key,
1479					  NULL);
1480}
1481
1482static int
1483apply_obj_config_object(struct bpf_object *obj)
1484{
1485	struct bpf_map *map;
1486	int err;
1487
1488	bpf_object__for_each_map(map, obj) {
1489		err = apply_obj_config_map(map);
1490		if (err)
1491			return err;
1492	}
1493	return 0;
1494}
1495
1496int bpf__apply_obj_config(void)
1497{
1498	struct bpf_object *obj, *tmp;
1499	int err;
1500
1501	bpf_object__for_each_safe(obj, tmp) {
1502		err = apply_obj_config_object(obj);
1503		if (err)
1504			return err;
1505	}
1506
1507	return 0;
1508}
1509
1510#define bpf__for_each_map(pos, obj, objtmp)	\
1511	bpf_object__for_each_safe(obj, objtmp)	\
1512		bpf_object__for_each_map(pos, obj)
1513
1514#define bpf__for_each_map_named(pos, obj, objtmp, name)	\
1515	bpf__for_each_map(pos, obj, objtmp) 		\
1516		if (bpf_map__name(pos) && 		\
1517			(strcmp(name, 			\
1518				bpf_map__name(pos)) == 0))
1519
1520struct evsel *bpf__setup_output_event(struct evlist *evlist, const char *name)
1521{
1522	struct bpf_map_priv *tmpl_priv = NULL;
1523	struct bpf_object *obj, *tmp;
1524	struct evsel *evsel = NULL;
1525	struct bpf_map *map;
1526	int err;
1527	bool need_init = false;
1528
1529	bpf__for_each_map_named(map, obj, tmp, name) {
1530		struct bpf_map_priv *priv = bpf_map__priv(map);
1531
1532		if (IS_ERR(priv))
1533			return ERR_PTR(-BPF_LOADER_ERRNO__INTERNAL);
1534
1535		/*
1536		 * No need to check map type: type should have been
1537		 * verified by kernel.
1538		 */
1539		if (!need_init && !priv)
1540			need_init = !priv;
1541		if (!tmpl_priv && priv)
1542			tmpl_priv = priv;
1543	}
1544
1545	if (!need_init)
1546		return NULL;
1547
1548	if (!tmpl_priv) {
1549		char *event_definition = NULL;
1550
1551		if (asprintf(&event_definition, "bpf-output/no-inherit=1,name=%s/", name) < 0)
1552			return ERR_PTR(-ENOMEM);
1553
1554		err = parse_events(evlist, event_definition, NULL);
1555		free(event_definition);
1556
1557		if (err) {
1558			pr_debug("ERROR: failed to create the \"%s\" bpf-output event\n", name);
1559			return ERR_PTR(-err);
1560		}
1561
1562		evsel = evlist__last(evlist);
1563	}
1564
1565	bpf__for_each_map_named(map, obj, tmp, name) {
1566		struct bpf_map_priv *priv = bpf_map__priv(map);
1567
1568		if (IS_ERR(priv))
1569			return ERR_PTR(-BPF_LOADER_ERRNO__INTERNAL);
1570		if (priv)
1571			continue;
1572
1573		if (tmpl_priv) {
1574			priv = bpf_map_priv__clone(tmpl_priv);
1575			if (!priv)
1576				return ERR_PTR(-ENOMEM);
1577
1578			err = bpf_map__set_priv(map, priv, bpf_map_priv__clear);
1579			if (err) {
1580				bpf_map_priv__clear(map, priv);
1581				return ERR_PTR(err);
1582			}
1583		} else if (evsel) {
1584			struct bpf_map_op *op;
1585
1586			op = bpf_map__add_newop(map, NULL);
1587			if (IS_ERR(op))
1588				return ERR_CAST(op);
1589			op->op_type = BPF_MAP_OP_SET_EVSEL;
1590			op->v.evsel = evsel;
1591		}
1592	}
1593
1594	return evsel;
1595}
1596
1597int bpf__setup_stdout(struct evlist *evlist)
1598{
1599	struct evsel *evsel = bpf__setup_output_event(evlist, "__bpf_stdout__");
1600	return PTR_ERR_OR_ZERO(evsel);
1601}
1602
1603#define ERRNO_OFFSET(e)		((e) - __BPF_LOADER_ERRNO__START)
1604#define ERRCODE_OFFSET(c)	ERRNO_OFFSET(BPF_LOADER_ERRNO__##c)
1605#define NR_ERRNO	(__BPF_LOADER_ERRNO__END - __BPF_LOADER_ERRNO__START)
1606
1607static const char *bpf_loader_strerror_table[NR_ERRNO] = {
1608	[ERRCODE_OFFSET(CONFIG)]	= "Invalid config string",
1609	[ERRCODE_OFFSET(GROUP)]		= "Invalid group name",
1610	[ERRCODE_OFFSET(EVENTNAME)]	= "No event name found in config string",
1611	[ERRCODE_OFFSET(INTERNAL)]	= "BPF loader internal error",
1612	[ERRCODE_OFFSET(COMPILE)]	= "Error when compiling BPF scriptlet",
1613	[ERRCODE_OFFSET(PROGCONF_TERM)]	= "Invalid program config term in config string",
1614	[ERRCODE_OFFSET(PROLOGUE)]	= "Failed to generate prologue",
1615	[ERRCODE_OFFSET(PROLOGUE2BIG)]	= "Prologue too big for program",
1616	[ERRCODE_OFFSET(PROLOGUEOOB)]	= "Offset out of bound for prologue",
1617	[ERRCODE_OFFSET(OBJCONF_OPT)]	= "Invalid object config option",
1618	[ERRCODE_OFFSET(OBJCONF_CONF)]	= "Config value not set (missing '=')",
1619	[ERRCODE_OFFSET(OBJCONF_MAP_OPT)]	= "Invalid object map config option",
1620	[ERRCODE_OFFSET(OBJCONF_MAP_NOTEXIST)]	= "Target map doesn't exist",
1621	[ERRCODE_OFFSET(OBJCONF_MAP_VALUE)]	= "Incorrect value type for map",
1622	[ERRCODE_OFFSET(OBJCONF_MAP_TYPE)]	= "Incorrect map type",
1623	[ERRCODE_OFFSET(OBJCONF_MAP_KEYSIZE)]	= "Incorrect map key size",
1624	[ERRCODE_OFFSET(OBJCONF_MAP_VALUESIZE)]	= "Incorrect map value size",
1625	[ERRCODE_OFFSET(OBJCONF_MAP_NOEVT)]	= "Event not found for map setting",
1626	[ERRCODE_OFFSET(OBJCONF_MAP_MAPSIZE)]	= "Invalid map size for event setting",
1627	[ERRCODE_OFFSET(OBJCONF_MAP_EVTDIM)]	= "Event dimension too large",
1628	[ERRCODE_OFFSET(OBJCONF_MAP_EVTINH)]	= "Doesn't support inherit event",
1629	[ERRCODE_OFFSET(OBJCONF_MAP_EVTTYPE)]	= "Wrong event type for map",
1630	[ERRCODE_OFFSET(OBJCONF_MAP_IDX2BIG)]	= "Index too large",
1631};
1632
1633static int
1634bpf_loader_strerror(int err, char *buf, size_t size)
1635{
1636	char sbuf[STRERR_BUFSIZE];
1637	const char *msg;
1638
1639	if (!buf || !size)
1640		return -1;
1641
1642	err = err > 0 ? err : -err;
1643
1644	if (err >= __LIBBPF_ERRNO__START)
1645		return libbpf_strerror(err, buf, size);
1646
1647	if (err >= __BPF_LOADER_ERRNO__START && err < __BPF_LOADER_ERRNO__END) {
1648		msg = bpf_loader_strerror_table[ERRNO_OFFSET(err)];
1649		snprintf(buf, size, "%s", msg);
1650		buf[size - 1] = '\0';
1651		return 0;
1652	}
1653
1654	if (err >= __BPF_LOADER_ERRNO__END)
1655		snprintf(buf, size, "Unknown bpf loader error %d", err);
1656	else
1657		snprintf(buf, size, "%s",
1658			 str_error_r(err, sbuf, sizeof(sbuf)));
1659
1660	buf[size - 1] = '\0';
1661	return -1;
1662}
1663
1664#define bpf__strerror_head(err, buf, size) \
1665	char sbuf[STRERR_BUFSIZE], *emsg;\
1666	if (!size)\
1667		return 0;\
1668	if (err < 0)\
1669		err = -err;\
1670	bpf_loader_strerror(err, sbuf, sizeof(sbuf));\
1671	emsg = sbuf;\
1672	switch (err) {\
1673	default:\
1674		scnprintf(buf, size, "%s", emsg);\
1675		break;
1676
1677#define bpf__strerror_entry(val, fmt...)\
1678	case val: {\
1679		scnprintf(buf, size, fmt);\
1680		break;\
1681	}
1682
1683#define bpf__strerror_end(buf, size)\
1684	}\
1685	buf[size - 1] = '\0';
1686
1687int bpf__strerror_prepare_load(const char *filename, bool source,
1688			       int err, char *buf, size_t size)
1689{
1690	size_t n;
1691	int ret;
1692
1693	n = snprintf(buf, size, "Failed to load %s%s: ",
1694			 filename, source ? " from source" : "");
1695	if (n >= size) {
1696		buf[size - 1] = '\0';
1697		return 0;
1698	}
1699	buf += n;
1700	size -= n;
1701
1702	ret = bpf_loader_strerror(err, buf, size);
1703	buf[size - 1] = '\0';
1704	return ret;
1705}
1706
1707int bpf__strerror_probe(struct bpf_object *obj __maybe_unused,
1708			int err, char *buf, size_t size)
1709{
1710	bpf__strerror_head(err, buf, size);
1711	case BPF_LOADER_ERRNO__PROGCONF_TERM: {
1712		scnprintf(buf, size, "%s (add -v to see detail)", emsg);
1713		break;
1714	}
1715	bpf__strerror_entry(EEXIST, "Probe point exist. Try 'perf probe -d \"*\"' and set 'force=yes'");
1716	bpf__strerror_entry(EACCES, "You need to be root");
1717	bpf__strerror_entry(EPERM, "You need to be root, and /proc/sys/kernel/kptr_restrict should be 0");
1718	bpf__strerror_entry(ENOENT, "You need to check probing points in BPF file");
1719	bpf__strerror_end(buf, size);
1720	return 0;
1721}
1722
1723int bpf__strerror_load(struct bpf_object *obj,
1724		       int err, char *buf, size_t size)
1725{
1726	bpf__strerror_head(err, buf, size);
1727	case LIBBPF_ERRNO__KVER: {
1728		unsigned int obj_kver = bpf_object__kversion(obj);
1729		unsigned int real_kver;
1730
1731		if (fetch_kernel_version(&real_kver, NULL, 0)) {
1732			scnprintf(buf, size, "Unable to fetch kernel version");
1733			break;
1734		}
1735
1736		if (obj_kver != real_kver) {
1737			scnprintf(buf, size,
1738				  "'version' ("KVER_FMT") doesn't match running kernel ("KVER_FMT")",
1739				  KVER_PARAM(obj_kver),
1740				  KVER_PARAM(real_kver));
1741			break;
1742		}
1743
1744		scnprintf(buf, size, "Failed to load program for unknown reason");
1745		break;
1746	}
1747	bpf__strerror_end(buf, size);
1748	return 0;
1749}
1750
1751int bpf__strerror_config_obj(struct bpf_object *obj __maybe_unused,
1752			     struct parse_events_term *term __maybe_unused,
1753			     struct evlist *evlist __maybe_unused,
1754			     int *error_pos __maybe_unused, int err,
1755			     char *buf, size_t size)
1756{
1757	bpf__strerror_head(err, buf, size);
1758	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE,
1759			    "Can't use this config term with this map type");
1760	bpf__strerror_end(buf, size);
1761	return 0;
1762}
1763
1764int bpf__strerror_apply_obj_config(int err, char *buf, size_t size)
1765{
1766	bpf__strerror_head(err, buf, size);
1767	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTDIM,
1768			    "Cannot set event to BPF map in multi-thread tracing");
1769	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTINH,
1770			    "%s (Hint: use -i to turn off inherit)", emsg);
1771	bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTTYPE,
1772			    "Can only put raw, hardware and BPF output event into a BPF map");
1773	bpf__strerror_end(buf, size);
1774	return 0;
1775}
1776
1777int bpf__strerror_setup_output_event(struct evlist *evlist __maybe_unused,
1778				     int err, char *buf, size_t size)
1779{
1780	bpf__strerror_head(err, buf, size);
1781	bpf__strerror_end(buf, size);
1782	return 0;
1783}