1 files changed, 35 insertions, 8 deletions

diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c
index e5bc97b71ceb..b3745ed711ba 100644
--- a/tools/bpf/bpftool/btf.c
+++ b/tools/bpf/bpftool/btf.c
@@ -8,15 +8,15 @@
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
-#include <bpf.h>
-#include <libbpf.h>
+#include <bpf/bpf.h>
+#include <bpf/btf.h>
+#include <bpf/libbpf.h>
 #include <linux/btf.h>
 #include <linux/hashtable.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <unistd.h>
 
-#include "btf.h"
 #include "json_writer.h"
 #include "main.h"
 
@@ -77,6 +77,20 @@ static const char *btf_var_linkage_str(__u32 linkage)
 	}
 }
 
+static const char *btf_func_linkage_str(const struct btf_type *t)
+{
+	switch (btf_vlen(t)) {
+	case BTF_FUNC_STATIC:
+		return "static";
+	case BTF_FUNC_GLOBAL:
+		return "global";
+	case BTF_FUNC_EXTERN:
+		return "extern";
+	default:
+		return "(unknown)";
+	}
+}
+
 static const char *btf_str(const struct btf *btf, __u32 off)
 {
 	if (!off)
@@ -231,12 +245,17 @@ static int dump_btf_type(const struct btf *btf, __u32 id,
 			printf(" fwd_kind=%s", fwd_kind);
 		break;
 	}
-	case BTF_KIND_FUNC:
-		if (json_output)
+	case BTF_KIND_FUNC: {
+		const char *linkage = btf_func_linkage_str(t);
+
+		if (json_output) {
 			jsonw_uint_field(w, "type_id", t->type);
-		else
-			printf(" type_id=%u", t->type);
+			jsonw_string_field(w, "linkage", linkage);
+		} else {
+			printf(" type_id=%u linkage=%s", t->type, linkage);
+		}
 		break;
+	}
 	case BTF_KIND_FUNC_PROTO: {
 		const struct btf_param *p = (const void *)(t + 1);
 		__u16 vlen = BTF_INFO_VLEN(t->info);
@@ -370,6 +389,10 @@ static int dump_btf_c(const struct btf *btf,
 	if (IS_ERR(d))
 		return PTR_ERR(d);
 
+	printf("#ifndef BPF_NO_PRESERVE_ACCESS_INDEX\n");
+	printf("#pragma clang attribute push (__attribute__((preserve_access_index)), apply_to = record)\n");
+	printf("#endif\n\n");
+
 	if (root_type_cnt) {
 		for (i = 0; i < root_type_cnt; i++) {
 			err = btf_dump__dump_type(d, root_type_ids[i]);
@@ -386,6 +409,10 @@ static int dump_btf_c(const struct btf *btf,
 		}
 	}
 
+	printf("#ifndef BPF_NO_PRESERVE_ACCESS_INDEX\n");
+	printf("#pragma clang attribute pop\n");
+	printf("#endif\n");
+
 done:
 	btf_dump__free(d);
 	return err;
@@ -524,7 +551,7 @@ static int do_dump(int argc, char **argv)
 		if (IS_ERR(btf)) {
 			err = PTR_ERR(btf);
 			btf = NULL;
-			p_err("failed to load BTF from %s: %s", 
+			p_err("failed to load BTF from %s: %s",
 			      *argv, strerror(err));
 			goto done;
 		}