Merge branch 'clean-up bpftool from legacy support'

Sahid Orentino Ferdjaoui says:

====================

As part of commit 93b8952d223a ("libbpf: deprecate legacy BPF map
definitions") and commit bd054102a8c7 ("libbpf: enforce strict libbpf
1.0 behaviors") The --legacy option is not relevant anymore. #1 is
removing it. #4 is cleaning the code from using libbpf_get_error().

About patches #2 and #3 They are changes discovered while working on
this series (credits to Quentin Monnet). #2 is cleaning-up usage of an
unnecessary PTR_ERR(NULL), finally #3 is fixing an invalid value
passed to strerror().

v1 -> v2:
   - Addressed review comments from Yonghong Song on patch #4
   - Added a patch #5 that removes unwanted function noticed by
     Yonghong Song
v2 -> v3
   - Addressed review comments from Andrii Nakryiko on patch #2, #3, #4
     * clean-up usage of libbpf_get_error() (#2, #3)
     * fix possible return of an uninitialized local variable err
     * fix returned errors using errno
v3 -> v4
   - Addressed review comments from Quentin Monnet
     * fix line moved from patch #2 to patch #3
     * fix missing returned errors using errno
     * fix some returned values to errno instead of -1
====================

Reviewed-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 9 insertions, 13 deletions

diff --git a/tools/bpf/bpftool/struct_ops.c b/tools/bpf/bpftool/struct_ops.c
index e08a6ff2866c..903b80ff4e9a 100644
--- a/tools/bpf/bpftool/struct_ops.c
+++ b/tools/bpf/bpftool/struct_ops.c
@@ -32,7 +32,7 @@ static const struct btf *get_btf_vmlinux(void)
 		return btf_vmlinux;
 
 	btf_vmlinux = libbpf_find_kernel_btf();
-	if (libbpf_get_error(btf_vmlinux))
+	if (!btf_vmlinux)
 		p_err("struct_ops requires kernel CONFIG_DEBUG_INFO_BTF=y");
 
 	return btf_vmlinux;
@@ -45,7 +45,7 @@ static const char *get_kern_struct_ops_name(const struct bpf_map_info *info)
 	const char *st_ops_name;
 
 	kern_btf = get_btf_vmlinux();
-	if (libbpf_get_error(kern_btf))
+	if (!kern_btf)
 		return "<btf_vmlinux_not_found>";
 
 	t = btf__type_by_id(kern_btf, info->btf_vmlinux_value_type_id);
@@ -63,10 +63,8 @@ static __s32 get_map_info_type_id(void)
 		return map_info_type_id;
 
 	kern_btf = get_btf_vmlinux();
-	if (libbpf_get_error(kern_btf)) {
-		map_info_type_id = PTR_ERR(kern_btf);
-		return map_info_type_id;
-	}
+	if (!kern_btf)
+		return 0;
 
 	map_info_type_id = btf__find_by_name_kind(kern_btf, "bpf_map_info",
 						  BTF_KIND_STRUCT);
@@ -415,7 +413,7 @@ static int do_dump(int argc, char **argv)
 	}
 
 	kern_btf = get_btf_vmlinux();
-	if (libbpf_get_error(kern_btf))
+	if (!kern_btf)
 		return -1;
 
 	if (!json_output) {
@@ -498,7 +496,7 @@ static int do_register(int argc, char **argv)
 		open_opts.kernel_log_level = 1 + 2 + 4;
 
 	obj = bpf_object__open_file(file, &open_opts);
-	if (libbpf_get_error(obj))
+	if (!obj)
 		return -1;
 
 	set_max_rlimit();
@@ -513,10 +511,9 @@ static int do_register(int argc, char **argv)
 			continue;
 
 		link = bpf_map__attach_struct_ops(map);
-		if (libbpf_get_error(link)) {
+		if (!link) {
 			p_err("can't register struct_ops %s: %s",
-			      bpf_map__name(map),
-			      strerror(-PTR_ERR(link)));
+			      bpf_map__name(map), strerror(errno));
 			nr_errs++;
 			continue;
 		}
@@ -593,8 +590,7 @@ int do_struct_ops(int argc, char **argv)
 
 	err = cmd_select(cmds, argc, argv, do_help);
 
-	if (!libbpf_get_error(btf_vmlinux))
-		btf__free(btf_vmlinux);
+	btf__free(btf_vmlinux);
 
 	return err;
 }