diff options
Diffstat (limited to 'tools/lib/bpf/libbpf.c')
-rw-r--r-- | tools/lib/bpf/libbpf.c | 156 |
1 files changed, 124 insertions, 32 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index 996162801f7a..085e41f9b68e 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -2284,9 +2284,16 @@ static void bpf_object__sanitize_btf_ext(struct bpf_object *obj) } } -static bool bpf_object__is_btf_mandatory(const struct bpf_object *obj) +static bool libbpf_needs_btf(const struct bpf_object *obj) { - return obj->efile.st_ops_shndx >= 0 || obj->nr_extern > 0; + return obj->efile.btf_maps_shndx >= 0 || + obj->efile.st_ops_shndx >= 0 || + obj->nr_extern > 0; +} + +static bool kernel_needs_btf(const struct bpf_object *obj) +{ + return obj->efile.st_ops_shndx >= 0; } static int bpf_object__init_btf(struct bpf_object *obj, @@ -2322,7 +2329,7 @@ static int bpf_object__init_btf(struct bpf_object *obj, } } out: - if (err && bpf_object__is_btf_mandatory(obj)) { + if (err && libbpf_needs_btf(obj)) { pr_warn("BTF is required, but is missing or corrupted.\n"); return err; } @@ -2346,7 +2353,7 @@ static int bpf_object__finalize_btf(struct bpf_object *obj) btf_ext__free(obj->btf_ext); obj->btf_ext = NULL; - if (bpf_object__is_btf_mandatory(obj)) { + if (libbpf_needs_btf(obj)) { pr_warn("BTF is required, but is missing or corrupted.\n"); return -ENOENT; } @@ -2410,7 +2417,7 @@ static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj) obj->btf_ext = NULL; } - if (bpf_object__is_btf_mandatory(obj)) + if (kernel_needs_btf(obj)) return err; } return 0; @@ -3866,6 +3873,10 @@ static struct ids_vec *bpf_core_find_cands(const struct btf *local_btf, if (str_is_empty(targ_name)) continue; + t = skip_mods_and_typedefs(targ_btf, i, NULL); + if (!btf_is_composite(t) && !btf_is_array(t)) + continue; + targ_essent_len = bpf_core_essential_name_len(targ_name); if (targ_essent_len != local_essent_len) continue; @@ -6288,6 +6299,10 @@ static const struct bpf_sec_def section_defs[] = { .expected_attach_type = BPF_TRACE_FENTRY, .is_attach_btf = true, .attach_fn = attach_trace), + SEC_DEF("fmod_ret/", TRACING, + .expected_attach_type = BPF_MODIFY_RETURN, + .is_attach_btf = true, + .attach_fn = attach_trace), SEC_DEF("fexit/", TRACING, .expected_attach_type = BPF_TRACE_FEXIT, .is_attach_btf = true, @@ -6931,6 +6946,8 @@ int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr, struct bpf_link { int (*detach)(struct bpf_link *link); int (*destroy)(struct bpf_link *link); + char *pin_path; /* NULL, if not pinned */ + int fd; /* hook FD, -1 if not applicable */ bool disconnected; }; @@ -6960,26 +6977,109 @@ int bpf_link__destroy(struct bpf_link *link) err = link->detach(link); if (link->destroy) link->destroy(link); + if (link->pin_path) + free(link->pin_path); free(link); return err; } -struct bpf_link_fd { - struct bpf_link link; /* has to be at the top of struct */ - int fd; /* hook FD */ -}; +int bpf_link__fd(const struct bpf_link *link) +{ + return link->fd; +} + +const char *bpf_link__pin_path(const struct bpf_link *link) +{ + return link->pin_path; +} + +static int bpf_link__detach_fd(struct bpf_link *link) +{ + return close(link->fd); +} + +struct bpf_link *bpf_link__open(const char *path) +{ + struct bpf_link *link; + int fd; + + fd = bpf_obj_get(path); + if (fd < 0) { + fd = -errno; + pr_warn("failed to open link at %s: %d\n", path, fd); + return ERR_PTR(fd); + } + + link = calloc(1, sizeof(*link)); + if (!link) { + close(fd); + return ERR_PTR(-ENOMEM); + } + link->detach = &bpf_link__detach_fd; + link->fd = fd; + + link->pin_path = strdup(path); + if (!link->pin_path) { + bpf_link__destroy(link); + return ERR_PTR(-ENOMEM); + } + + return link; +} + +int bpf_link__pin(struct bpf_link *link, const char *path) +{ + int err; + + if (link->pin_path) + return -EBUSY; + err = make_parent_dir(path); + if (err) + return err; + err = check_path(path); + if (err) + return err; + + link->pin_path = strdup(path); + if (!link->pin_path) + return -ENOMEM; + + if (bpf_obj_pin(link->fd, link->pin_path)) { + err = -errno; + zfree(&link->pin_path); + return err; + } + + pr_debug("link fd=%d: pinned at %s\n", link->fd, link->pin_path); + return 0; +} + +int bpf_link__unpin(struct bpf_link *link) +{ + int err; + + if (!link->pin_path) + return -EINVAL; + + err = unlink(link->pin_path); + if (err != 0) + return -errno; + + pr_debug("link fd=%d: unpinned from %s\n", link->fd, link->pin_path); + zfree(&link->pin_path); + return 0; +} static int bpf_link__detach_perf_event(struct bpf_link *link) { - struct bpf_link_fd *l = (void *)link; int err; - err = ioctl(l->fd, PERF_EVENT_IOC_DISABLE, 0); + err = ioctl(link->fd, PERF_EVENT_IOC_DISABLE, 0); if (err) err = -errno; - close(l->fd); + close(link->fd); return err; } @@ -6987,7 +7087,7 @@ struct bpf_link *bpf_program__attach_perf_event(struct bpf_program *prog, int pfd) { char errmsg[STRERR_BUFSIZE]; - struct bpf_link_fd *link; + struct bpf_link *link; int prog_fd, err; if (pfd < 0) { @@ -7005,7 +7105,7 @@ struct bpf_link *bpf_program__attach_perf_event(struct bpf_program *prog, link = calloc(1, sizeof(*link)); if (!link) return ERR_PTR(-ENOMEM); - link->link.detach = &bpf_link__detach_perf_event; + link->detach = &bpf_link__detach_perf_event; link->fd = pfd; if (ioctl(pfd, PERF_EVENT_IOC_SET_BPF, prog_fd) < 0) { @@ -7024,7 +7124,7 @@ struct bpf_link *bpf_program__attach_perf_event(struct bpf_program *prog, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); return ERR_PTR(err); } - return (struct bpf_link *)link; + return link; } /* @@ -7312,18 +7412,11 @@ out: return link; } -static int bpf_link__detach_fd(struct bpf_link *link) -{ - struct bpf_link_fd *l = (void *)link; - - return close(l->fd); -} - struct bpf_link *bpf_program__attach_raw_tracepoint(struct bpf_program *prog, const char *tp_name) { char errmsg[STRERR_BUFSIZE]; - struct bpf_link_fd *link; + struct bpf_link *link; int prog_fd, pfd; prog_fd = bpf_program__fd(prog); @@ -7336,7 +7429,7 @@ struct bpf_link *bpf_program__attach_raw_tracepoint(struct bpf_program *prog, link = calloc(1, sizeof(*link)); if (!link) return ERR_PTR(-ENOMEM); - link->link.detach = &bpf_link__detach_fd; + link->detach = &bpf_link__detach_fd; pfd = bpf_raw_tracepoint_open(tp_name, prog_fd); if (pfd < 0) { @@ -7348,7 +7441,7 @@ struct bpf_link *bpf_program__attach_raw_tracepoint(struct bpf_program *prog, return ERR_PTR(pfd); } link->fd = pfd; - return (struct bpf_link *)link; + return link; } static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec, @@ -7362,7 +7455,7 @@ static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec, struct bpf_link *bpf_program__attach_trace(struct bpf_program *prog) { char errmsg[STRERR_BUFSIZE]; - struct bpf_link_fd *link; + struct bpf_link *link; int prog_fd, pfd; prog_fd = bpf_program__fd(prog); @@ -7375,7 +7468,7 @@ struct bpf_link *bpf_program__attach_trace(struct bpf_program *prog) link = calloc(1, sizeof(*link)); if (!link) return ERR_PTR(-ENOMEM); - link->link.detach = &bpf_link__detach_fd; + link->detach = &bpf_link__detach_fd; pfd = bpf_raw_tracepoint_open(NULL, prog_fd); if (pfd < 0) { @@ -7409,10 +7502,9 @@ struct bpf_link *bpf_program__attach(struct bpf_program *prog) static int bpf_link__detach_struct_ops(struct bpf_link *link) { - struct bpf_link_fd *l = (void *)link; __u32 zero = 0; - if (bpf_map_delete_elem(l->fd, &zero)) + if (bpf_map_delete_elem(link->fd, &zero)) return -errno; return 0; @@ -7421,7 +7513,7 @@ static int bpf_link__detach_struct_ops(struct bpf_link *link) struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map) { struct bpf_struct_ops *st_ops; - struct bpf_link_fd *link; + struct bpf_link *link; __u32 i, zero = 0; int err; @@ -7453,10 +7545,10 @@ struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map) return ERR_PTR(err); } - link->link.detach = bpf_link__detach_struct_ops; + link->detach = bpf_link__detach_struct_ops; link->fd = map->fd; - return (struct bpf_link *)link; + return link; } enum bpf_perf_event_ret |