1 files changed, 29 insertions, 7 deletions

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 846164c79df1..7be04e45d29c 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -6504,7 +6504,7 @@ void bpf_object__close(struct bpf_object *obj)
 {
 	size_t i;
 
-	if (!obj)
+	if (IS_ERR_OR_NULL(obj))
 		return;
 
 	if (obj->clear_priv)
@@ -6915,7 +6915,8 @@ static const struct bpf_sec_def section_defs[] = {
 						BPF_XDP_DEVMAP),
 	BPF_EAPROG_SEC("xdp_cpumap/",		BPF_PROG_TYPE_XDP,
 						BPF_XDP_CPUMAP),
-	BPF_PROG_SEC("xdp",			BPF_PROG_TYPE_XDP),
+	BPF_EAPROG_SEC("xdp",			BPF_PROG_TYPE_XDP,
+						BPF_XDP),
 	BPF_PROG_SEC("perf_event",		BPF_PROG_TYPE_PERF_EVENT),
 	BPF_PROG_SEC("lwt_in",			BPF_PROG_TYPE_LWT_IN),
 	BPF_PROG_SEC("lwt_out",			BPF_PROG_TYPE_LWT_OUT),
@@ -7689,7 +7690,7 @@ int bpf_link__destroy(struct bpf_link *link)
 {
 	int err = 0;
 
-	if (!link)
+	if (IS_ERR_OR_NULL(link))
 		return 0;
 
 	if (!link->disconnected && link->detach)
@@ -7747,6 +7748,11 @@ struct bpf_link *bpf_link__open(const char *path)
 	return link;
 }
 
+int bpf_link__detach(struct bpf_link *link)
+{
+	return bpf_link_detach(link->fd) ? -errno : 0;
+}
+
 int bpf_link__pin(struct bpf_link *link, const char *path)
 {
 	int err;
@@ -7833,6 +7839,9 @@ struct bpf_link *bpf_program__attach_perf_event(struct bpf_program *prog,
 		pr_warn("program '%s': failed to attach to pfd %d: %s\n",
 			bpf_program__title(prog, false), pfd,
 			   libbpf_strerror_r(err, errmsg, sizeof(errmsg)));
+		if (err == -EPROTO)
+			pr_warn("program '%s': try add PERF_SAMPLE_CALLCHAIN to or remove exclude_callchain_[kernel|user] from pfd %d\n",
+				bpf_program__title(prog, false), pfd);
 		return ERR_PTR(err);
 	}
 	if (ioctl(pfd, PERF_EVENT_IOC_ENABLE, 0) < 0) {
@@ -8278,17 +8287,30 @@ bpf_program__attach_netns(struct bpf_program *prog, int netns_fd)
 	return bpf_program__attach_fd(prog, netns_fd, "netns");
 }
 
+struct bpf_link *bpf_program__attach_xdp(struct bpf_program *prog, int ifindex)
+{
+	/* target_fd/target_ifindex use the same field in LINK_CREATE */
+	return bpf_program__attach_fd(prog, ifindex, "xdp");
+}
+
 struct bpf_link *
 bpf_program__attach_iter(struct bpf_program *prog,
 			 const struct bpf_iter_attach_opts *opts)
 {
+	DECLARE_LIBBPF_OPTS(bpf_link_create_opts, link_create_opts);
 	char errmsg[STRERR_BUFSIZE];
 	struct bpf_link *link;
 	int prog_fd, link_fd;
+	__u32 target_fd = 0;
 
 	if (!OPTS_VALID(opts, bpf_iter_attach_opts))
 		return ERR_PTR(-EINVAL);
 
+	if (OPTS_HAS(opts, map_fd)) {
+		target_fd = opts->map_fd;
+		link_create_opts.flags = BPF_ITER_LINK_MAP_FD;
+	}
+
 	prog_fd = bpf_program__fd(prog);
 	if (prog_fd < 0) {
 		pr_warn("program '%s': can't attach before loaded\n",
@@ -8301,7 +8323,8 @@ bpf_program__attach_iter(struct bpf_program *prog,
 		return ERR_PTR(-ENOMEM);
 	link->detach = &bpf_link__detach_fd;
 
-	link_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_ITER, NULL);
+	link_fd = bpf_link_create(prog_fd, target_fd, BPF_TRACE_ITER,
+				  &link_create_opts);
 	if (link_fd < 0) {
 		link_fd = -errno;
 		free(link);
@@ -8484,7 +8507,7 @@ void perf_buffer__free(struct perf_buffer *pb)
 {
 	int i;
 
-	if (!pb)
+	if (IS_ERR_OR_NULL(pb))
 		return;
 	if (pb->cpu_bufs) {
 		for (i = 0; i < pb->cpu_cnt; i++) {
@@ -9361,8 +9384,7 @@ void bpf_object__detach_skeleton(struct bpf_object_skeleton *s)
 	for (i = 0; i < s->prog_cnt; i++) {
 		struct bpf_link **link = s->progs[i].link;
 
-		if (!IS_ERR_OR_NULL(*link))
-			bpf_link__destroy(*link);
+		bpf_link__destroy(*link);
 		*link = NULL;
 	}
 }