// SPDX-License-Identifier: GPL-2.0 /* * bpf-loader.c * * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com> * Copyright (C) 2015 Huawei Inc. */ #include <linux/bpf.h> #include <bpf/libbpf.h> #include <bpf/bpf.h> #include <linux/filter.h> #include <linux/err.h> #include <linux/kernel.h> #include <linux/string.h> #include <linux/zalloc.h> #include <errno.h> #include <stdlib.h> #include "debug.h" #include "evlist.h" #include "bpf-loader.h" #include "bpf-prologue.h" #include "probe-event.h" #include "probe-finder.h" // for MAX_PROBES #include "parse-events.h" #include "strfilter.h" #include "util.h" #include "llvm-utils.h" #include "c++/clang-c.h" #ifdef HAVE_LIBBPF_SUPPORT #include <bpf/hashmap.h> #else #include "util/hashmap.h" #endif #include "asm/bug.h" #include <internal/xyarray.h> #ifndef HAVE_LIBBPF_BPF_PROGRAM__SET_INSNS int bpf_program__set_insns(struct bpf_program *prog __maybe_unused, struct bpf_insn *new_insns __maybe_unused, size_t new_insn_cnt __maybe_unused) { pr_err("%s: not support, update libbpf\n", __func__); return -ENOTSUP; } int libbpf_register_prog_handler(const char *sec __maybe_unused, enum bpf_prog_type prog_type __maybe_unused, enum bpf_attach_type exp_attach_type __maybe_unused, const struct libbpf_prog_handler_opts *opts __maybe_unused) { pr_err("%s: not support, update libbpf\n", __func__); return -ENOTSUP; } #endif /* temporarily disable libbpf deprecation warnings */ #pragma GCC diagnostic ignored "-Wdeprecated-declarations" static int libbpf_perf_print(enum libbpf_print_level level __attribute__((unused)), const char *fmt, va_list args) { return veprintf(1, verbose, pr_fmt(fmt), args); } struct bpf_prog_priv { bool is_tp; char *sys_name; char *evt_name; struct perf_probe_event pev; bool need_prologue; struct bpf_insn *insns_buf; int nr_types; int *type_mapping; int *prologue_fds; }; struct bpf_perf_object { struct list_head list; struct bpf_object *obj; }; struct bpf_preproc_result { struct bpf_insn *new_insn_ptr; int new_insn_cnt; }; static LIST_HEAD(bpf_objects_list); static struct hashmap *bpf_program_hash; static struct hashmap *bpf_map_hash; static struct bpf_perf_object * bpf_perf_object__next(struct bpf_perf_object *prev) { if (!prev) { if (list_empty(&bpf_objects_list)) return NULL; return list_first_entry(&bpf_objects_list, struct bpf_perf_object, list); } if (list_is_last(&prev->list, &bpf_objects_list)) return NULL; return list_next_entry(prev, list); } #define bpf_perf_object__for_each(perf_obj, tmp) \ for ((perf_obj) = bpf_perf_object__next(NULL), \ (tmp) = bpf_perf_object__next(perf_obj); \ (perf_obj) != NULL; \ (perf_obj) = (tmp), (tmp) = bpf_perf_object__next(tmp)) static bool libbpf_initialized; static int libbpf_sec_handler; static int bpf_perf_object__add(struct bpf_object *obj) { struct bpf_perf_object *perf_obj = zalloc(sizeof(*perf_obj)); if (perf_obj) { INIT_LIST_HEAD(&perf_obj->list); perf_obj->obj = obj; list_add_tail(&perf_obj->list, &bpf_objects_list); } return perf_obj ? 0 : -ENOMEM; } static void *program_priv(const struct bpf_program *prog) { void *priv; if (IS_ERR_OR_NULL(bpf_program_hash)) return NULL; if (!hashmap__find(bpf_program_hash, prog, &priv)) return NULL; return priv; } static struct bpf_insn prologue_init_insn[] = { BPF_MOV64_IMM(BPF_REG_2, 0), BPF_MOV64_IMM(BPF_REG_3, 0), BPF_MOV64_IMM(BPF_REG_4, 0), BPF_MOV64_IMM(BPF_REG_5, 0), }; static int libbpf_prog_prepare_load_fn(struct bpf_program *prog, struct bpf_prog_load_opts *opts __maybe_unused, long cookie __maybe_unused) { size_t init_size_cnt = ARRAY_SIZE(prologue_init_insn); size_t orig_insn_cnt, insn_cnt, init_size, orig_size; struct bpf_prog_priv *priv = program_priv(prog); const struct bpf_insn *orig_insn; struct bpf_insn *insn; if (IS_ERR_OR_NULL(priv)) { pr_debug("bpf: failed to get private field\n"); return -BPF_LOADER_ERRNO__INTERNAL; } if (!priv->need_prologue) return 0; /* prepend initialization code to program instructions */ orig_insn = bpf_program__insns(prog); orig_insn_cnt = bpf_program__insn_cnt(prog); init_size = init_size_cnt * sizeof(*insn); orig_size = orig_insn_cnt * sizeof(*insn); insn_cnt = orig_insn_cnt + init_size_cnt; insn = malloc(insn_cnt * sizeof(*insn)); if (!insn) return -ENOMEM; memcpy(insn, prologue_init_insn, init_size); memcpy((char *) insn + init_size, orig_insn, orig_size); bpf_program__set_insns(prog, insn, insn_cnt); return 0; } static int libbpf_init(void) { LIBBPF_OPTS(libbpf_prog_handler_opts, handler_opts, .prog_prepare_load_fn = libbpf_prog_prepare_load_fn, ); if (libbpf_initialized) return 0; libbpf_set_print(libbpf_perf_print); libbpf_sec_handler = libbpf_register_prog_handler(NULL, BPF_PROG_TYPE_KPROBE, 0, &handler_opts); if (libbpf_sec_handler < 0) { pr_debug("bpf: failed to register libbpf section handler: %d\n", libbpf_sec_handler); return -BPF_LOADER_ERRNO__INTERNAL; } libbpf_initialized = true; return 0; } struct bpf_object * bpf__prepare_load_buffer(void *obj_buf, size_t obj_buf_sz, const char *name) { LIBBPF_OPTS(bpf_object_open_opts, opts, .object_name = name); struct bpf_object *obj; int err; err = libbpf_init(); if (err) return ERR_PTR(err); obj = bpf_object__open_mem(obj_buf, obj_buf_sz, &opts); if (IS_ERR_OR_NULL(obj)) { pr_debug("bpf: failed to load buffer\n"); return ERR_PTR(-EINVAL); } if (bpf_perf_object__add(obj)) { bpf_object__close(obj); return ERR_PTR(-ENOMEM); } return obj; } static void bpf_perf_object__close(struct bpf_perf_object *perf_obj) { list_del(&perf_obj->list); bpf_object__close(perf_obj->obj); free(perf_obj); } struct bpf_object *bpf__prepare_load(const char *filename, bool source) { LIBBPF_OPTS(bpf_object_open_opts, opts, .object_name = filename); struct bpf_object *obj; int err; err = libbpf_init(); if (err) return ERR_PTR(err); if (source) { void *obj_buf; size_t obj_buf_sz; perf_clang__init(); err = perf_clang__compile_bpf(filename, &obj_buf, &obj_buf_sz); perf_clang__cleanup(); if (err) { pr_debug("bpf: builtin compilation failed: %d, try external compiler\n", err); err = llvm__compile_bpf(filename, &obj_buf, &obj_buf_sz); if (err) return ERR_PTR(-BPF_LOADER_ERRNO__COMPILE); } else pr_debug("bpf: successful builtin compilation\n"); obj = bpf_object__open_mem(obj_buf, obj_buf_sz, &opts); if (!IS_ERR_OR_NULL(obj) && llvm_param.dump_obj) llvm__dump_obj(filename, obj_buf, obj_buf_sz); free(obj_buf); } else { obj = bpf_object__open(filename); } if (IS_ERR_OR_NULL(obj)) { pr_debug("bpf: failed to load %s\n", filename); return obj; } if (bpf_perf_object__add(obj)) { bpf_object__close(obj); return ERR_PTR(-BPF_LOADER_ERRNO__COMPILE); } return obj; } static void close_prologue_programs(struct bpf_prog_priv *priv) { struct perf_probe_event *pev; int i, fd; if (!priv->need_prologue) return; pev = &priv->pev; for (i = 0; i < pev->ntevs; i++) { fd = priv->prologue_fds[i]; if (fd != -1) close(fd); } } static void clear_prog_priv(const struct bpf_program *prog __maybe_unused, void *_priv) { struct bpf_prog_priv *priv = _priv; close_prologue_programs(priv); cleanup_perf_probe_events(&priv->pev, 1); zfree(&priv->insns_buf); zfree(&priv->prologue_fds); zfree(&priv->type_mapping); zfree(&priv->sys_name); zfree(&priv->evt_name); free(priv); } static void bpf_program_hash_free(void) { struct hashmap_entry *cur; size_t bkt; if (IS_ERR_OR_NULL(bpf_program_hash)) return; hashmap__for_each_entry(bpf_program_hash, cur, bkt) clear_prog_priv(cur->key, cur->value); hashmap__free(bpf_program_hash); bpf_program_hash = NULL; } static void bpf_map_hash_free(void); void bpf__clear(void) { struct bpf_perf_object *perf_obj, *tmp; bpf_perf_object__for_each(perf_obj, tmp) { bpf__unprobe(perf_obj->obj); bpf_perf_object__close(perf_obj); } bpf_program_hash_free(); bpf_map_hash_free(); } static size_t ptr_hash(const void *__key, void *ctx __maybe_unused) { return (size_t) __key; } static bool ptr_equal(const void *key1, const void *key2, void *ctx __maybe_unused) { return key1 == key2; } static int program_set_priv(struct bpf_program *prog, void *priv) { void *old_priv; /* * Should not happen, we warn about it in the * caller function - config_bpf_program */ if (IS_ERR(bpf_program_hash)) return PTR_ERR(bpf_program_hash); if (!bpf_program_hash) { bpf_program_hash = hashmap__new(ptr_hash, ptr_equal, NULL); if (IS_ERR(bpf_program_hash)) return PTR_ERR(bpf_program_hash); } old_priv = program_priv(prog); if (old_priv) { clear_prog_priv(prog, old_priv); return hashmap__set(bpf_program_hash, prog, priv, NULL, NULL); } return hashmap__add(bpf_program_hash, prog, priv); } static int prog_config__exec(const char *value, struct perf_probe_event *pev) { pev->uprobes = true; pev->target = strdup(value); if (!pev->target) return -ENOMEM; return 0; } static int prog_config__module(const char *value, struct perf_probe_event *pev) { pev->uprobes = false; pev->target = strdup(value); if (!pev->target) return -ENOMEM; return 0; } static int prog_config__bool(const char *value, bool *pbool, bool invert) { int err; bool bool_value; if (!pbool) return -EINVAL; err = strtobool(value, &bool_value); if (err) return err; *pbool = invert ? !bool_value : bool_value; return 0; } static int prog_config__inlines(const char *value, struct perf_probe_event *pev __maybe_unused) { return prog_config__bool(value, &probe_conf.no_inlines, true); } static int prog_config__force(const char *value, struct perf_probe_event *pev __maybe_unused) { return prog_config__bool(value, &probe_conf.force_add, false); } static struct { const char *key; const char *usage; const char *desc; int (*func)(const char *, struct perf_probe_event *); } bpf_prog_config_terms[] = { { .key = "exec", .usage = "exec=<full path of file>", .desc = "Set uprobe target", .func = prog_config__exec, }, { .key = "module", .usage = "module=<module name> ", .desc = "Set kprobe module", .func = prog_config__module, }, { .key = "inlines", .usage = "inlines=[yes|no] ", .desc = "Probe at inline symbol", .func = prog_config__inlines, }, { .key = "force", .usage = "force=[yes|no] ", .desc = "Forcibly add events with existing name", .func = prog_config__force, }, }; static int do_prog_config(const char *key, const char *value, struct perf_probe_event *pev) { unsigned int i; pr_debug("config bpf program: %s=%s\n", key, value); for (i = 0; i < ARRAY_SIZE(bpf_prog_config_terms); i++) if (strcmp(key, bpf_prog_config_terms[i].key) == 0) return bpf_prog_config_terms[i].func(value, pev); pr_debug("BPF: ERROR: invalid program config option: %s=%s\n", key, value); pr_debug("\nHint: Valid options are:\n"); for (i = 0; i < ARRAY_SIZE(bpf_prog_config_terms); i++) pr_debug("\t%s:\t%s\n", bpf_prog_config_terms[i].usage, bpf_prog_config_terms[i].desc); pr_debug("\n"); return -BPF_LOADER_ERRNO__PROGCONF_TERM; } static const char * parse_prog_config_kvpair(const char *config_str, struct perf_probe_event *pev) { char *text = strdup(config_str); char *sep, *line; const char *main_str = NULL; int err = 0; if (!text) { pr_debug("Not enough memory: dup config_str failed\n"); return ERR_PTR(-ENOMEM); } line = text; while ((sep = strchr(line, ';'))) { char *equ; *sep = '\0'; equ = strchr(line, '='); if (!equ) { pr_warning("WARNING: invalid config in BPF object: %s\n", line); pr_warning("\tShould be 'key=value'.\n"); goto nextline; } *equ = '\0'; err = do_prog_config(line, equ + 1, pev); if (err) break; nextline: line = sep + 1; } if (!err) main_str = config_str + (line - text); free(text); return err ? ERR_PTR(err) : main_str; } static int parse_prog_config(const char *config_str, const char **p_main_str, bool *is_tp, struct perf_probe_event *pev) { int err; const char *main_str = parse_prog_config_kvpair(config_str, pev); if (IS_ERR(main_str)) return PTR_ERR(main_str); *p_main_str = main_str; if (!strchr(main_str, '=')) { /* Is a tracepoint event? */ const char *s = strchr(main_str, ':'); if (!s) { pr_debug("bpf: '%s' is not a valid tracepoint\n", config_str); return -BPF_LOADER_ERRNO__CONFIG; } *is_tp = true; return 0; } *is_tp = false; err = parse_perf_probe_command(main_str, pev); if (err < 0) { pr_debug("bpf: '%s' is not a valid config string\n", config_str); /* parse failed, don't need clear pev. */ return -BPF_LOADER_ERRNO__CONFIG; } return 0; } static int config_bpf_program(struct bpf_program *prog) { struct perf_probe_event *pev = NULL; struct bpf_prog_priv *priv = NULL; const char *config_str, *main_str; bool is_tp = false; int err; /* Initialize per-program probing setting */ probe_conf.no_inlines = false; probe_conf.force_add = false; priv = calloc(sizeof(*priv), 1); if (!priv) { pr_debug("bpf: failed to alloc priv\n"); return -ENOMEM; } pev = &priv->pev; config_str = bpf_program__section_name(prog); pr_debug("bpf: config program '%s'\n", config_str); err = parse_prog_config(config_str, &main_str, &is_tp, pev); if (err) goto errout; if (is_tp) { char *s = strchr(main_str, ':'); priv->is_tp = true; priv->sys_name = strndup(main_str, s - main_str); priv->evt_name = strdup(s + 1); goto set_priv; } if (pev->group && strcmp(pev->group, PERF_BPF_PROBE_GROUP)) { pr_debug("bpf: '%s': group for event is set and not '%s'.\n", config_str, PERF_BPF_PROBE_GROUP); err = -BPF_LOADER_ERRNO__GROUP; goto errout; } else if (!pev->group) pev->group = strdup(PERF_BPF_PROBE_GROUP); if (!pev->group) { pr_debug("bpf: strdup failed\n"); err = -ENOMEM; goto errout; } if (!pev->event) { pr_debug("bpf: '%s': event name is missing. Section name should be 'key=value'\n", config_str); err = -BPF_LOADER_ERRNO__EVENTNAME; goto errout; } pr_debug("bpf: config '%s' is ok\n", config_str); set_priv: err = program_set_priv(prog, priv); if (err) { pr_debug("Failed to set priv for program '%s'\n", config_str); goto errout; } return 0; errout: if (pev) clear_perf_probe_event(pev); free(priv); return err; } static int bpf__prepare_probe(void) { static int err = 0; static bool initialized = false; /* * Make err static, so if init failed the first, bpf__prepare_probe() * fails each time without calling init_probe_symbol_maps multiple * times. */ if (initialized) return err; initialized = true; err = init_probe_symbol_maps(false); if (err < 0) pr_debug("Failed to init_probe_symbol_maps\n"); probe_conf.max_probes = MAX_PROBES; return err; } static int preproc_gen_prologue(struct bpf_program *prog, int n, const struct bpf_insn *orig_insns, int orig_insns_cnt, struct bpf_preproc_result *res) { struct bpf_prog_priv *priv = program_priv(prog); struct probe_trace_event *tev; struct perf_probe_event *pev; struct bpf_insn *buf; size_t prologue_cnt = 0; int i, err; if (IS_ERR_OR_NULL(priv) || priv->is_tp) goto errout; pev = &priv->pev; if (n < 0 || n >= priv->nr_types) goto errout; /* Find a tev belongs to that type */ for (i = 0; i < pev->ntevs; i++) { if (priv->type_mapping[i] == n) break; } if (i >= pev->ntevs) { pr_debug("Internal error: prologue type %d not found\n", n); return -BPF_LOADER_ERRNO__PROLOGUE; } tev = &pev->tevs[i]; buf = priv->insns_buf; err = bpf__gen_prologue(tev->args, tev->nargs, buf, &prologue_cnt, BPF_MAXINSNS - orig_insns_cnt); if (err) { const char *title; title = bpf_program__section_name(prog); pr_debug("Failed to generate prologue for program %s\n", title); return err; } memcpy(&buf[prologue_cnt], orig_insns, sizeof(struct bpf_insn) * orig_insns_cnt); res->new_insn_ptr = buf; res->new_insn_cnt = prologue_cnt + orig_insns_cnt; return 0; errout: pr_debug("Internal error in preproc_gen_prologue\n"); return -BPF_LOADER_ERRNO__PROLOGUE; } /* * compare_tev_args is reflexive, transitive and antisymmetric. * I can proof it but this margin is too narrow to contain. */ static int compare_tev_args(const void *ptev1, const void *ptev2) { int i, ret; const struct probe_trace_event *tev1 = *(const struct probe_trace_event **)ptev1; const struct probe_trace_event *tev2 = *(const struct probe_trace_event **)ptev2; ret = tev2->nargs - tev1->nargs; if (ret) return ret; for (i = 0; i < tev1->nargs; i++) { struct probe_trace_arg *arg1, *arg2; struct probe_trace_arg_ref *ref1, *ref2; arg1 = &tev1->args[i]; arg2 = &tev2->args[i]; ret = strcmp(arg1->value, arg2->value); if (ret) return ret; ref1 = arg1->ref; ref2 = arg2->ref; while (ref1 && ref2) { ret = ref2->offset - ref1->offset; if (ret) return ret; ref1 = ref1->next; ref2 = ref2->next; } if (ref1 || ref2) return ref2 ? 1 : -1; } return 0; } /* * Assign a type number to each tevs in a pev. * mapping is an array with same slots as tevs in that pev. * nr_types will be set to number of types. */ static int map_prologue(struct perf_probe_event *pev, int *mapping, int *nr_types) { int i, type = 0; struct probe_trace_event **ptevs; size_t array_sz = sizeof(*ptevs) * pev->ntevs; ptevs = malloc(array_sz); if (!ptevs) { pr_debug("Not enough memory: alloc ptevs failed\n"); return -ENOMEM; } pr_debug("In map_prologue, ntevs=%d\n", pev->ntevs); for (i = 0; i < pev->ntevs; i++) ptevs[i] = &pev->tevs[i]; qsort(ptevs, pev->ntevs, sizeof(*ptevs), compare_tev_args); for (i = 0; i < pev->ntevs; i++) { int n; n = ptevs[i] - pev->tevs; if (i == 0) { mapping[n] = type; pr_debug("mapping[%d]=%d\n", n, type); continue; } if (compare_tev_args(ptevs + i, ptevs + i - 1) == 0) mapping[n] = type; else mapping[n] = ++type; pr_debug("mapping[%d]=%d\n", n, mapping[n]); } free(ptevs); *nr_types = type + 1; return 0; } static int hook_load_preprocessor(struct bpf_program *prog) { struct bpf_prog_priv *priv = program_priv(prog); struct perf_probe_event *pev; bool need_prologue = false; int i; if (IS_ERR_OR_NULL(priv)) { pr_debug("Internal error when hook preprocessor\n"); return -BPF_LOADER_ERRNO__INTERNAL; } if (priv->is_tp) { priv->need_prologue = false; return 0; } pev = &priv->pev; for (i = 0; i < pev->ntevs; i++) { struct probe_trace_event *tev = &pev->tevs[i]; if (tev->nargs > 0) { need_prologue = true; break; } } /* * Since all tevs don't have argument, we don't need generate * prologue. */ if (!need_prologue) { priv->need_prologue = false; return 0; } priv->need_prologue = true; priv->insns_buf = malloc(sizeof(struct bpf_insn) * BPF_MAXINSNS); if (!priv->insns_buf) { pr_debug("Not enough memory: alloc insns_buf failed\n"); return -ENOMEM; } priv->prologue_fds = malloc(sizeof(int) * pev->ntevs); if (!priv->prologue_fds) { pr_debug("Not enough memory: alloc prologue fds failed\n"); return -ENOMEM; } memset(priv->prologue_fds, -1, sizeof(int) * pev->ntevs); priv->type_mapping = malloc(sizeof(int) * pev->ntevs); if (!priv->type_mapping) { pr_debug("Not enough memory: alloc type_mapping failed\n"); return -ENOMEM; } memset(priv->type_mapping, -1, sizeof(int) * pev->ntevs); return map_prologue(pev, priv->type_mapping, &priv->nr_types); } int bpf__probe(struct bpf_object *obj) { int err = 0; struct bpf_program *prog; struct bpf_prog_priv *priv; struct perf_probe_event *pev; err = bpf__prepare_probe(); if (err) { pr_debug("bpf__prepare_probe failed\n"); return err; } bpf_object__for_each_program(prog, obj) { err = config_bpf_program(prog); if (err) goto out; priv = program_priv(prog); if (IS_ERR_OR_NULL(priv)) { if (!priv) err = -BPF_LOADER_ERRNO__INTERNAL; else err = PTR_ERR(priv); goto out; } if (priv->is_tp) { bpf_program__set_type(prog, BPF_PROG_TYPE_TRACEPOINT); continue; } bpf_program__set_type(prog, BPF_PROG_TYPE_KPROBE); pev = &priv->pev; err = convert_perf_probe_events(pev, 1); if (err < 0) { pr_debug("bpf_probe: failed to convert perf probe events\n"); goto out; } err = apply_perf_probe_events(pev, 1); if (err < 0) { pr_debug("bpf_probe: failed to apply perf probe events\n"); goto out; } /* * After probing, let's consider prologue, which * adds program fetcher to BPF programs. * * hook_load_preprocessor() hooks pre-processor * to bpf_program, let it generate prologue * dynamically during loading. */ err = hook_load_preprocessor(prog); if (err) goto out; } out: return err < 0 ? err : 0; } #define EVENTS_WRITE_BUFSIZE 4096 int bpf__unprobe(struct bpf_object *obj) { int err, ret = 0; struct bpf_program *prog; bpf_object__for_each_program(prog, obj) { struct bpf_prog_priv *priv = program_priv(prog); int i; if (IS_ERR_OR_NULL(priv) || priv->is_tp) continue; for (i = 0; i < priv->pev.ntevs; i++) { struct probe_trace_event *tev = &priv->pev.tevs[i]; char name_buf[EVENTS_WRITE_BUFSIZE]; struct strfilter *delfilter; snprintf(name_buf, EVENTS_WRITE_BUFSIZE, "%s:%s", tev->group, tev->event); name_buf[EVENTS_WRITE_BUFSIZE - 1] = '\0'; delfilter = strfilter__new(name_buf, NULL); if (!delfilter) { pr_debug("Failed to create filter for unprobing\n"); ret = -ENOMEM; continue; } err = del_perf_probe_events(delfilter); strfilter__delete(delfilter); if (err) { pr_debug("Failed to delete %s\n", name_buf); ret = err; continue; } } } return ret; } static int bpf_object__load_prologue(struct bpf_object *obj) { int init_cnt = ARRAY_SIZE(prologue_init_insn); const struct bpf_insn *orig_insns; struct bpf_preproc_result res; struct perf_probe_event *pev; struct bpf_program *prog; int orig_insns_cnt; bpf_object__for_each_program(prog, obj) { struct bpf_prog_priv *priv = program_priv(prog); int err, i, fd; if (IS_ERR_OR_NULL(priv)) { pr_debug("bpf: failed to get private field\n"); return -BPF_LOADER_ERRNO__INTERNAL; } if (!priv->need_prologue) continue; /* * For each program that needs prologue we do following: * * - take its current instructions and use them * to generate the new code with prologue * - load new instructions with bpf_prog_load * and keep the fd in prologue_fds * - new fd will be used in bpf__foreach_event * to connect this program with perf evsel */ orig_insns = bpf_program__insns(prog); orig_insns_cnt = bpf_program__insn_cnt(prog); pev = &priv->pev; for (i = 0; i < pev->ntevs; i++) { /* * Skipping artificall prologue_init_insn instructions * (init_cnt), so the prologue can be generated instead * of them. */ err = preproc_gen_prologue(prog, i, orig_insns + init_cnt, orig_insns_cnt - init_cnt, &res); if (err) return err; fd = bpf_prog_load(bpf_program__get_type(prog), bpf_program__name(prog), "GPL", res.new_insn_ptr, res.new_insn_cnt, NULL); if (fd < 0) { char bf[128]; libbpf_strerror(-errno, bf, sizeof(bf)); pr_debug("bpf: load objects with prologue failed: err=%d: (%s)\n", -errno, bf); return -errno; } priv->prologue_fds[i] = fd; } /* * We no longer need the original program, * we can unload it. */ bpf_program__unload(prog); } return 0; } int bpf__load(struct bpf_object *obj) { int err; err = bpf_object__load(obj); if (err) { char bf[128]; libbpf_strerror(err, bf, sizeof(bf)); pr_debug("bpf: load objects failed: err=%d: (%s)\n", err, bf); return err; } return bpf_object__load_prologue(obj); } int bpf__foreach_event(struct bpf_object *obj, bpf_prog_iter_callback_t func, void *arg) { struct bpf_program *prog; int err; bpf_object__for_each_program(prog, obj) { struct bpf_prog_priv *priv = program_priv(prog); struct probe_trace_event *tev; struct perf_probe_event *pev; int i, fd; if (IS_ERR_OR_NULL(priv)) { pr_debug("bpf: failed to get private field\n"); return -BPF_LOADER_ERRNO__INTERNAL; } if (priv->is_tp) { fd = bpf_program__fd(prog); err = (*func)(priv->sys_name, priv->evt_name, fd, obj, arg); if (err) { pr_debug("bpf: tracepoint call back failed, stop iterate\n"); return err; } continue; } pev = &priv->pev; for (i = 0; i < pev->ntevs; i++) { tev = &pev->tevs[i]; if (priv->need_prologue) fd = priv->prologue_fds[i]; else fd = bpf_program__fd(prog); if (fd < 0) { pr_debug("bpf: failed to get file descriptor\n"); return fd; } err = (*func)(tev->group, tev->event, fd, obj, arg); if (err) { pr_debug("bpf: call back failed, stop iterate\n"); return err; } } } return 0; } enum bpf_map_op_type { BPF_MAP_OP_SET_VALUE, BPF_MAP_OP_SET_EVSEL, }; enum bpf_map_key_type { BPF_MAP_KEY_ALL, BPF_MAP_KEY_RANGES, }; struct bpf_map_op { struct list_head list; enum bpf_map_op_type op_type; enum bpf_map_key_type key_type; union { struct parse_events_array array; } k; union { u64 value; struct evsel *evsel; } v; }; struct bpf_map_priv { struct list_head ops_list; }; static void bpf_map_op__delete(struct bpf_map_op *op) { if (!list_empty(&op->list)) list_del_init(&op->list); if (op->key_type == BPF_MAP_KEY_RANGES) parse_events__clear_array(&op->k.array); free(op); } static void bpf_map_priv__purge(struct bpf_map_priv *priv) { struct bpf_map_op *pos, *n; list_for_each_entry_safe(pos, n, &priv->ops_list, list) { list_del_init(&pos->list); bpf_map_op__delete(pos); } } static void bpf_map_priv__clear(const struct bpf_map *map __maybe_unused, void *_priv) { struct bpf_map_priv *priv = _priv; bpf_map_priv__purge(priv); free(priv); } static void *map_priv(const struct bpf_map *map) { void *priv; if (IS_ERR_OR_NULL(bpf_map_hash)) return NULL; if (!hashmap__find(bpf_map_hash, map, &priv)) return NULL; return priv; } static void bpf_map_hash_free(void) { struct hashmap_entry *cur; size_t bkt; if (IS_ERR_OR_NULL(bpf_map_hash)) return; hashmap__for_each_entry(bpf_map_hash, cur, bkt) bpf_map_priv__clear(cur->key, cur->value); hashmap__free(bpf_map_hash); bpf_map_hash = NULL; } static int map_set_priv(struct bpf_map *map, void *priv) { void *old_priv; if (WARN_ON_ONCE(IS_ERR(bpf_map_hash))) return PTR_ERR(bpf_program_hash); if (!bpf_map_hash) { bpf_map_hash = hashmap__new(ptr_hash, ptr_equal, NULL); if (IS_ERR(bpf_map_hash)) return PTR_ERR(bpf_map_hash); } old_priv = map_priv(map); if (old_priv) { bpf_map_priv__clear(map, old_priv); return hashmap__set(bpf_map_hash, map, priv, NULL, NULL); } return hashmap__add(bpf_map_hash, map, priv); } static int bpf_map_op_setkey(struct bpf_map_op *op, struct parse_events_term *term) { op->key_type = BPF_MAP_KEY_ALL; if (!term) return 0; if (term->array.nr_ranges) { size_t memsz = term->array.nr_ranges * sizeof(op->k.array.ranges[0]); op->k.array.ranges = memdup(term->array.ranges, memsz); if (!op->k.array.ranges) { pr_debug("Not enough memory to alloc indices for map\n"); return -ENOMEM; } op->key_type = BPF_MAP_KEY_RANGES; op->k.array.nr_ranges = term->array.nr_ranges; } return 0; } static struct bpf_map_op * bpf_map_op__new(struct parse_events_term *term) { struct bpf_map_op *op; int err; op = zalloc(sizeof(*op)); if (!op) { pr_debug("Failed to alloc bpf_map_op\n"); return ERR_PTR(-ENOMEM); } INIT_LIST_HEAD(&op->list); err = bpf_map_op_setkey(op, term); if (err) { free(op); return ERR_PTR(err); } return op; } static struct bpf_map_op * bpf_map_op__clone(struct bpf_map_op *op) { struct bpf_map_op *newop; newop = memdup(op, sizeof(*op)); if (!newop) { pr_debug("Failed to alloc bpf_map_op\n"); return NULL; } INIT_LIST_HEAD(&newop->list); if (op->key_type == BPF_MAP_KEY_RANGES) { size_t memsz = op->k.array.nr_ranges * sizeof(op->k.array.ranges[0]); newop->k.array.ranges = memdup(op->k.array.ranges, memsz); if (!newop->k.array.ranges) { pr_debug("Failed to alloc indices for map\n"); free(newop); return NULL; } } return newop; } static struct bpf_map_priv * bpf_map_priv__clone(struct bpf_map_priv *priv) { struct bpf_map_priv *newpriv; struct bpf_map_op *pos, *newop; newpriv = zalloc(sizeof(*newpriv)); if (!newpriv) { pr_debug("Not enough memory to alloc map private\n"); return NULL; } INIT_LIST_HEAD(&newpriv->ops_list); list_for_each_entry(pos, &priv->ops_list, list) { newop = bpf_map_op__clone(pos); if (!newop) { bpf_map_priv__purge(newpriv); return NULL; } list_add_tail(&newop->list, &newpriv->ops_list); } return newpriv; } static int bpf_map__add_op(struct bpf_map *map, struct bpf_map_op *op) { const char *map_name = bpf_map__name(map); struct bpf_map_priv *priv = map_priv(map); if (IS_ERR(priv)) { pr_debug("Failed to get private from map %s\n", map_name); return PTR_ERR(priv); } if (!priv) { priv = zalloc(sizeof(*priv)); if (!priv) { pr_debug("Not enough memory to alloc map private\n"); return -ENOMEM; } INIT_LIST_HEAD(&priv->ops_list); if (map_set_priv(map, priv)) { free(priv); return -BPF_LOADER_ERRNO__INTERNAL; } } list_add_tail(&op->list, &priv->ops_list); return 0; } static struct bpf_map_op * bpf_map__add_newop(struct bpf_map *map, struct parse_events_term *term) { struct bpf_map_op *op; int err; op = bpf_map_op__new(term); if (IS_ERR(op)) return op; err = bpf_map__add_op(map, op); if (err) { bpf_map_op__delete(op); return ERR_PTR(err); } return op; } static int __bpf_map__config_value(struct bpf_map *map, struct parse_events_term *term) { struct bpf_map_op *op; const char *map_name = bpf_map__name(map); if (!map) { pr_debug("Map '%s' is invalid\n", map_name); return -BPF_LOADER_ERRNO__INTERNAL; } if (bpf_map__type(map) != BPF_MAP_TYPE_ARRAY) { pr_debug("Map %s type is not BPF_MAP_TYPE_ARRAY\n", map_name); return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE; } if (bpf_map__key_size(map) < sizeof(unsigned int)) { pr_debug("Map %s has incorrect key size\n", map_name); return -BPF_LOADER_ERRNO__OBJCONF_MAP_KEYSIZE; } switch (bpf_map__value_size(map)) { case 1: case 2: case 4: case 8: break; default: pr_debug("Map %s has incorrect value size\n", map_name); return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE; } op = bpf_map__add_newop(map, term); if (IS_ERR(op)) return PTR_ERR(op); op->op_type = BPF_MAP_OP_SET_VALUE; op->v.value = term->val.num; return 0; } static int bpf_map__config_value(struct bpf_map *map, struct parse_events_term *term, struct evlist *evlist __maybe_unused) { if (!term->err_val) { pr_debug("Config value not set\n"); return -BPF_LOADER_ERRNO__OBJCONF_CONF; } if (term->type_val != PARSE_EVENTS__TERM_TYPE_NUM) { pr_debug("ERROR: wrong value type for 'value'\n"); return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE; } return __bpf_map__config_value(map, term); } static int __bpf_map__config_event(struct bpf_map *map, struct parse_events_term *term, struct evlist *evlist) { struct bpf_map_op *op; const char *map_name = bpf_map__name(map); struct evsel *evsel = evlist__find_evsel_by_str(evlist, term->val.str); if (!evsel) { pr_debug("Event (for '%s') '%s' doesn't exist\n", map_name, term->val.str); return -BPF_LOADER_ERRNO__OBJCONF_MAP_NOEVT; } if (!map) { pr_debug("Map '%s' is invalid\n", map_name); return PTR_ERR(map); } /* * No need to check key_size and value_size: * kernel has already checked them. */ if (bpf_map__type(map) != BPF_MAP_TYPE_PERF_EVENT_ARRAY) { pr_debug("Map %s type is not BPF_MAP_TYPE_PERF_EVENT_ARRAY\n", map_name); return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE; } op = bpf_map__add_newop(map, term); if (IS_ERR(op)) return PTR_ERR(op); op->op_type = BPF_MAP_OP_SET_EVSEL; op->v.evsel = evsel; return 0; } static int bpf_map__config_event(struct bpf_map *map, struct parse_events_term *term, struct evlist *evlist) { if (!term->err_val) { pr_debug("Config value not set\n"); return -BPF_LOADER_ERRNO__OBJCONF_CONF; } if (term->type_val != PARSE_EVENTS__TERM_TYPE_STR) { pr_debug("ERROR: wrong value type for 'event'\n"); return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUE; } return __bpf_map__config_event(map, term, evlist); } struct bpf_obj_config__map_func { const char *config_opt; int (*config_func)(struct bpf_map *, struct parse_events_term *, struct evlist *); }; struct bpf_obj_config__map_func bpf_obj_config__map_funcs[] = { {"value", bpf_map__config_value}, {"event", bpf_map__config_event}, }; static int config_map_indices_range_check(struct parse_events_term *term, struct bpf_map *map, const char *map_name) { struct parse_events_array *array = &term->array; unsigned int i; if (!array->nr_ranges) return 0; if (!array->ranges) { pr_debug("ERROR: map %s: array->nr_ranges is %d but range array is NULL\n", map_name, (int)array->nr_ranges); return -BPF_LOADER_ERRNO__INTERNAL; } if (!map) { pr_debug("Map '%s' is invalid\n", map_name); return -BPF_LOADER_ERRNO__INTERNAL; } for (i = 0; i < array->nr_ranges; i++) { unsigned int start = array->ranges[i].start; size_t length = array->ranges[i].length; unsigned int idx = start + length - 1; if (idx >= bpf_map__max_entries(map)) { pr_debug("ERROR: index %d too large\n", idx); return -BPF_LOADER_ERRNO__OBJCONF_MAP_IDX2BIG; } } return 0; } static int bpf__obj_config_map(struct bpf_object *obj, struct parse_events_term *term, struct evlist *evlist, int *key_scan_pos) { /* key is "map:<mapname>.<config opt>" */ char *map_name = strdup(term->config + sizeof("map:") - 1); struct bpf_map *map; int err = -BPF_LOADER_ERRNO__OBJCONF_OPT; char *map_opt; size_t i; if (!map_name) return -ENOMEM; map_opt = strchr(map_name, '.'); if (!map_opt) { pr_debug("ERROR: Invalid map config: %s\n", map_name); goto out; } *map_opt++ = '\0'; if (*map_opt == '\0') { pr_debug("ERROR: Invalid map option: %s\n", term->config); goto out; } map = bpf_object__find_map_by_name(obj, map_name); if (!map) { pr_debug("ERROR: Map %s doesn't exist\n", map_name); err = -BPF_LOADER_ERRNO__OBJCONF_MAP_NOTEXIST; goto out; } *key_scan_pos += strlen(map_opt); err = config_map_indices_range_check(term, map, map_name); if (err) goto out; *key_scan_pos -= strlen(map_opt); for (i = 0; i < ARRAY_SIZE(bpf_obj_config__map_funcs); i++) { struct bpf_obj_config__map_func *func = &bpf_obj_config__map_funcs[i]; if (strcmp(map_opt, func->config_opt) == 0) { err = func->config_func(map, term, evlist); goto out; } } pr_debug("ERROR: Invalid map config option '%s'\n", map_opt); err = -BPF_LOADER_ERRNO__OBJCONF_MAP_OPT; out: if (!err) *key_scan_pos += strlen(map_opt); free(map_name); return err; } int bpf__config_obj(struct bpf_object *obj, struct parse_events_term *term, struct evlist *evlist, int *error_pos) { int key_scan_pos = 0; int err; if (!obj || !term || !term->config) return -EINVAL; if (strstarts(term->config, "map:")) { key_scan_pos = sizeof("map:") - 1; err = bpf__obj_config_map(obj, term, evlist, &key_scan_pos); goto out; } err = -BPF_LOADER_ERRNO__OBJCONF_OPT; out: if (error_pos) *error_pos = key_scan_pos; return err; } typedef int (*map_config_func_t)(const char *name, int map_fd, const struct bpf_map *map, struct bpf_map_op *op, void *pkey, void *arg); static int foreach_key_array_all(map_config_func_t func, void *arg, const char *name, int map_fd, const struct bpf_map *map, struct bpf_map_op *op) { unsigned int i; int err; for (i = 0; i < bpf_map__max_entries(map); i++) { err = func(name, map_fd, map, op, &i, arg); if (err) { pr_debug("ERROR: failed to insert value to %s[%u]\n", name, i); return err; } } return 0; } static int foreach_key_array_ranges(map_config_func_t func, void *arg, const char *name, int map_fd, const struct bpf_map *map, struct bpf_map_op *op) { unsigned int i, j; int err; for (i = 0; i < op->k.array.nr_ranges; i++) { unsigned int start = op->k.array.ranges[i].start; size_t length = op->k.array.ranges[i].length; for (j = 0; j < length; j++) { unsigned int idx = start + j; err = func(name, map_fd, map, op, &idx, arg); if (err) { pr_debug("ERROR: failed to insert value to %s[%u]\n", name, idx); return err; } } } return 0; } static int bpf_map_config_foreach_key(struct bpf_map *map, map_config_func_t func, void *arg) { int err, map_fd, type; struct bpf_map_op *op; const char *name = bpf_map__name(map); struct bpf_map_priv *priv = map_priv(map); if (IS_ERR(priv)) { pr_debug("ERROR: failed to get private from map %s\n", name); return -BPF_LOADER_ERRNO__INTERNAL; } if (!priv || list_empty(&priv->ops_list)) { pr_debug("INFO: nothing to config for map %s\n", name); return 0; } if (!map) { pr_debug("Map '%s' is invalid\n", name); return -BPF_LOADER_ERRNO__INTERNAL; } map_fd = bpf_map__fd(map); if (map_fd < 0) { pr_debug("ERROR: failed to get fd from map %s\n", name); return map_fd; } type = bpf_map__type(map); list_for_each_entry(op, &priv->ops_list, list) { switch (type) { case BPF_MAP_TYPE_ARRAY: case BPF_MAP_TYPE_PERF_EVENT_ARRAY: switch (op->key_type) { case BPF_MAP_KEY_ALL: err = foreach_key_array_all(func, arg, name, map_fd, map, op); break; case BPF_MAP_KEY_RANGES: err = foreach_key_array_ranges(func, arg, name, map_fd, map, op); break; default: pr_debug("ERROR: keytype for map '%s' invalid\n", name); return -BPF_LOADER_ERRNO__INTERNAL; } if (err) return err; break; default: pr_debug("ERROR: type of '%s' incorrect\n", name); return -BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE; } } return 0; } static int apply_config_value_for_key(int map_fd, void *pkey, size_t val_size, u64 val) { int err = 0; switch (val_size) { case 1: { u8 _val = (u8)(val); err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY); break; } case 2: { u16 _val = (u16)(val); err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY); break; } case 4: { u32 _val = (u32)(val); err = bpf_map_update_elem(map_fd, pkey, &_val, BPF_ANY); break; } case 8: { err = bpf_map_update_elem(map_fd, pkey, &val, BPF_ANY); break; } default: pr_debug("ERROR: invalid value size\n"); return -BPF_LOADER_ERRNO__OBJCONF_MAP_VALUESIZE; } if (err && errno) err = -errno; return err; } static int apply_config_evsel_for_key(const char *name, int map_fd, void *pkey, struct evsel *evsel) { struct xyarray *xy = evsel->core.fd; struct perf_event_attr *attr; unsigned int key, events; bool check_pass = false; int *evt_fd; int err; if (!xy) { pr_debug("ERROR: evsel not ready for map %s\n", name); return -BPF_LOADER_ERRNO__INTERNAL; } if (xy->row_size / xy->entry_size != 1) { pr_debug("ERROR: Dimension of target event is incorrect for map %s\n", name); return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTDIM; } attr = &evsel->core.attr; if (attr->inherit) { pr_debug("ERROR: Can't put inherit event into map %s\n", name); return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTINH; } if (evsel__is_bpf_output(evsel)) check_pass = true; if (attr->type == PERF_TYPE_RAW) check_pass = true; if (attr->type == PERF_TYPE_HARDWARE) check_pass = true; if (!check_pass) { pr_debug("ERROR: Event type is wrong for map %s\n", name); return -BPF_LOADER_ERRNO__OBJCONF_MAP_EVTTYPE; } events = xy->entries / (xy->row_size / xy->entry_size); key = *((unsigned int *)pkey); if (key >= events) { pr_debug("ERROR: there is no event %d for map %s\n", key, name); return -BPF_LOADER_ERRNO__OBJCONF_MAP_MAPSIZE; } evt_fd = xyarray__entry(xy, key, 0); err = bpf_map_update_elem(map_fd, pkey, evt_fd, BPF_ANY); if (err && errno) err = -errno; return err; } static int apply_obj_config_map_for_key(const char *name, int map_fd, const struct bpf_map *map, struct bpf_map_op *op, void *pkey, void *arg __maybe_unused) { int err; switch (op->op_type) { case BPF_MAP_OP_SET_VALUE: err = apply_config_value_for_key(map_fd, pkey, bpf_map__value_size(map), op->v.value); break; case BPF_MAP_OP_SET_EVSEL: err = apply_config_evsel_for_key(name, map_fd, pkey, op->v.evsel); break; default: pr_debug("ERROR: unknown value type for '%s'\n", name); err = -BPF_LOADER_ERRNO__INTERNAL; } return err; } static int apply_obj_config_map(struct bpf_map *map) { return bpf_map_config_foreach_key(map, apply_obj_config_map_for_key, NULL); } static int apply_obj_config_object(struct bpf_object *obj) { struct bpf_map *map; int err; bpf_object__for_each_map(map, obj) { err = apply_obj_config_map(map); if (err) return err; } return 0; } int bpf__apply_obj_config(void) { struct bpf_perf_object *perf_obj, *tmp; int err; bpf_perf_object__for_each(perf_obj, tmp) { err = apply_obj_config_object(perf_obj->obj); if (err) return err; } return 0; } #define bpf__perf_for_each_map(map, pobj, tmp) \ bpf_perf_object__for_each(pobj, tmp) \ bpf_object__for_each_map(map, pobj->obj) #define bpf__perf_for_each_map_named(map, pobj, pobjtmp, name) \ bpf__perf_for_each_map(map, pobj, pobjtmp) \ if (bpf_map__name(map) && (strcmp(name, bpf_map__name(map)) == 0)) struct evsel *bpf__setup_output_event(struct evlist *evlist, const char *name) { struct bpf_map_priv *tmpl_priv = NULL; struct bpf_perf_object *perf_obj, *tmp; struct evsel *evsel = NULL; struct bpf_map *map; int err; bool need_init = false; bpf__perf_for_each_map_named(map, perf_obj, tmp, name) { struct bpf_map_priv *priv = map_priv(map); if (IS_ERR(priv)) return ERR_PTR(-BPF_LOADER_ERRNO__INTERNAL); /* * No need to check map type: type should have been * verified by kernel. */ if (!need_init && !priv) need_init = !priv; if (!tmpl_priv && priv) tmpl_priv = priv; } if (!need_init) return NULL; if (!tmpl_priv) { char *event_definition = NULL; if (asprintf(&event_definition, "bpf-output/no-inherit=1,name=%s/", name) < 0) return ERR_PTR(-ENOMEM); err = parse_event(evlist, event_definition); free(event_definition); if (err) { pr_debug("ERROR: failed to create the \"%s\" bpf-output event\n", name); return ERR_PTR(-err); } evsel = evlist__last(evlist); } bpf__perf_for_each_map_named(map, perf_obj, tmp, name) { struct bpf_map_priv *priv = map_priv(map); if (IS_ERR(priv)) return ERR_PTR(-BPF_LOADER_ERRNO__INTERNAL); if (priv) continue; if (tmpl_priv) { priv = bpf_map_priv__clone(tmpl_priv); if (!priv) return ERR_PTR(-ENOMEM); err = map_set_priv(map, priv); if (err) { bpf_map_priv__clear(map, priv); return ERR_PTR(err); } } else if (evsel) { struct bpf_map_op *op; op = bpf_map__add_newop(map, NULL); if (IS_ERR(op)) return ERR_CAST(op); op->op_type = BPF_MAP_OP_SET_EVSEL; op->v.evsel = evsel; } } return evsel; } int bpf__setup_stdout(struct evlist *evlist) { struct evsel *evsel = bpf__setup_output_event(evlist, "__bpf_stdout__"); return PTR_ERR_OR_ZERO(evsel); } #define ERRNO_OFFSET(e) ((e) - __BPF_LOADER_ERRNO__START) #define ERRCODE_OFFSET(c) ERRNO_OFFSET(BPF_LOADER_ERRNO__##c) #define NR_ERRNO (__BPF_LOADER_ERRNO__END - __BPF_LOADER_ERRNO__START) static const char *bpf_loader_strerror_table[NR_ERRNO] = { [ERRCODE_OFFSET(CONFIG)] = "Invalid config string", [ERRCODE_OFFSET(GROUP)] = "Invalid group name", [ERRCODE_OFFSET(EVENTNAME)] = "No event name found in config string", [ERRCODE_OFFSET(INTERNAL)] = "BPF loader internal error", [ERRCODE_OFFSET(COMPILE)] = "Error when compiling BPF scriptlet", [ERRCODE_OFFSET(PROGCONF_TERM)] = "Invalid program config term in config string", [ERRCODE_OFFSET(PROLOGUE)] = "Failed to generate prologue", [ERRCODE_OFFSET(PROLOGUE2BIG)] = "Prologue too big for program", [ERRCODE_OFFSET(PROLOGUEOOB)] = "Offset out of bound for prologue", [ERRCODE_OFFSET(OBJCONF_OPT)] = "Invalid object config option", [ERRCODE_OFFSET(OBJCONF_CONF)] = "Config value not set (missing '=')", [ERRCODE_OFFSET(OBJCONF_MAP_OPT)] = "Invalid object map config option", [ERRCODE_OFFSET(OBJCONF_MAP_NOTEXIST)] = "Target map doesn't exist", [ERRCODE_OFFSET(OBJCONF_MAP_VALUE)] = "Incorrect value type for map", [ERRCODE_OFFSET(OBJCONF_MAP_TYPE)] = "Incorrect map type", [ERRCODE_OFFSET(OBJCONF_MAP_KEYSIZE)] = "Incorrect map key size", [ERRCODE_OFFSET(OBJCONF_MAP_VALUESIZE)] = "Incorrect map value size", [ERRCODE_OFFSET(OBJCONF_MAP_NOEVT)] = "Event not found for map setting", [ERRCODE_OFFSET(OBJCONF_MAP_MAPSIZE)] = "Invalid map size for event setting", [ERRCODE_OFFSET(OBJCONF_MAP_EVTDIM)] = "Event dimension too large", [ERRCODE_OFFSET(OBJCONF_MAP_EVTINH)] = "Doesn't support inherit event", [ERRCODE_OFFSET(OBJCONF_MAP_EVTTYPE)] = "Wrong event type for map", [ERRCODE_OFFSET(OBJCONF_MAP_IDX2BIG)] = "Index too large", }; static int bpf_loader_strerror(int err, char *buf, size_t size) { char sbuf[STRERR_BUFSIZE]; const char *msg; if (!buf || !size) return -1; err = err > 0 ? err : -err; if (err >= __LIBBPF_ERRNO__START) return libbpf_strerror(err, buf, size); if (err >= __BPF_LOADER_ERRNO__START && err < __BPF_LOADER_ERRNO__END) { msg = bpf_loader_strerror_table[ERRNO_OFFSET(err)]; snprintf(buf, size, "%s", msg); buf[size - 1] = '\0'; return 0; } if (err >= __BPF_LOADER_ERRNO__END) snprintf(buf, size, "Unknown bpf loader error %d", err); else snprintf(buf, size, "%s", str_error_r(err, sbuf, sizeof(sbuf))); buf[size - 1] = '\0'; return -1; } #define bpf__strerror_head(err, buf, size) \ char sbuf[STRERR_BUFSIZE], *emsg;\ if (!size)\ return 0;\ if (err < 0)\ err = -err;\ bpf_loader_strerror(err, sbuf, sizeof(sbuf));\ emsg = sbuf;\ switch (err) {\ default:\ scnprintf(buf, size, "%s", emsg);\ break; #define bpf__strerror_entry(val, fmt...)\ case val: {\ scnprintf(buf, size, fmt);\ break;\ } #define bpf__strerror_end(buf, size)\ }\ buf[size - 1] = '\0'; int bpf__strerror_prepare_load(const char *filename, bool source, int err, char *buf, size_t size) { size_t n; int ret; n = snprintf(buf, size, "Failed to load %s%s: ", filename, source ? " from source" : ""); if (n >= size) { buf[size - 1] = '\0'; return 0; } buf += n; size -= n; ret = bpf_loader_strerror(err, buf, size); buf[size - 1] = '\0'; return ret; } int bpf__strerror_probe(struct bpf_object *obj __maybe_unused, int err, char *buf, size_t size) { bpf__strerror_head(err, buf, size); case BPF_LOADER_ERRNO__PROGCONF_TERM: { scnprintf(buf, size, "%s (add -v to see detail)", emsg); break; } bpf__strerror_entry(EEXIST, "Probe point exist. Try 'perf probe -d \"*\"' and set 'force=yes'"); bpf__strerror_entry(EACCES, "You need to be root"); bpf__strerror_entry(EPERM, "You need to be root, and /proc/sys/kernel/kptr_restrict should be 0"); bpf__strerror_entry(ENOENT, "You need to check probing points in BPF file"); bpf__strerror_end(buf, size); return 0; } int bpf__strerror_load(struct bpf_object *obj, int err, char *buf, size_t size) { bpf__strerror_head(err, buf, size); case LIBBPF_ERRNO__KVER: { unsigned int obj_kver = bpf_object__kversion(obj); unsigned int real_kver; if (fetch_kernel_version(&real_kver, NULL, 0)) { scnprintf(buf, size, "Unable to fetch kernel version"); break; } if (obj_kver != real_kver) { scnprintf(buf, size, "'version' ("KVER_FMT") doesn't match running kernel ("KVER_FMT")", KVER_PARAM(obj_kver), KVER_PARAM(real_kver)); break; } scnprintf(buf, size, "Failed to load program for unknown reason"); break; } bpf__strerror_end(buf, size); return 0; } int bpf__strerror_config_obj(struct bpf_object *obj __maybe_unused, struct parse_events_term *term __maybe_unused, struct evlist *evlist __maybe_unused, int *error_pos __maybe_unused, int err, char *buf, size_t size) { bpf__strerror_head(err, buf, size); bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_TYPE, "Can't use this config term with this map type"); bpf__strerror_end(buf, size); return 0; } int bpf__strerror_apply_obj_config(int err, char *buf, size_t size) { bpf__strerror_head(err, buf, size); bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTDIM, "Cannot set event to BPF map in multi-thread tracing"); bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTINH, "%s (Hint: use -i to turn off inherit)", emsg); bpf__strerror_entry(BPF_LOADER_ERRNO__OBJCONF_MAP_EVTTYPE, "Can only put raw, hardware and BPF output event into a BPF map"); bpf__strerror_end(buf, size); return 0; } int bpf__strerror_setup_output_event(struct evlist *evlist __maybe_unused, int err, char *buf, size_t size) { bpf__strerror_head(err, buf, size); bpf__strerror_end(buf, size); return 0; }