[PATCH v2 2/9] libbpf: Introduce bpf_obj_get_flags()

[Roberto Sassu <roberto.sassu@huawei.com>]

Introduce the bpf_obj_get_flags() function, so that it is possible to
specify the needed permissions for obtaining a file descriptor from a
pinned object.

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
---
 tools/lib/bpf/bpf.c      | 8 +++++++-
 tools/lib/bpf/bpf.h      | 1 +
 tools/lib/bpf/libbpf.map | 1 +
 3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 33bac2006043..a5fc40f6ce13 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -670,18 +670,24 @@ int bpf_obj_pin(int fd, const char *pathname)
 	return libbpf_err_errno(ret);
 }
 
-int bpf_obj_get(const char *pathname)
+int bpf_obj_get_flags(const char *pathname, __u32 flags)
 {
 	union bpf_attr attr;
 	int fd;
 
 	memset(&attr, 0, sizeof(attr));
 	attr.pathname = ptr_to_u64((void *)pathname);
+	attr.file_flags = flags;
 
 	fd = sys_bpf_fd(BPF_OBJ_GET, &attr, sizeof(attr));
 	return libbpf_err_errno(fd);
 }
 
+int bpf_obj_get(const char *pathname)
+{
+	return bpf_obj_get_flags(pathname, 0);
+}
+
 int bpf_prog_attach(int prog_fd, int target_fd, enum bpf_attach_type type,
 		    unsigned int flags)
 {
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 20e4c852362d..6d0ceb2e90c4 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -339,6 +339,7 @@ LIBBPF_API int bpf_map_update_batch(int fd, const void *keys, const void *values
 				    const struct bpf_map_batch_opts *opts);
 
 LIBBPF_API int bpf_obj_pin(int fd, const char *pathname);
+LIBBPF_API int bpf_obj_get_flags(const char *pathname, __u32 flags);
 LIBBPF_API int bpf_obj_get(const char *pathname);
 
 struct bpf_prog_attach_opts {
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index 019278e66836..6c3ace12b27b 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -467,6 +467,7 @@ LIBBPF_1.0.0 {
 		libbpf_bpf_map_type_str;
 		libbpf_bpf_prog_type_str;
 		bpf_map_get_fd_by_id_flags;
+		bpf_obj_get_flags;
 
 	local: *;
 };
-- 
2.25.1