bpf_link_info.iter is used by link_query to return bpf_iter_link_info
to user space. Fields may be different, e.g., map_fd vs. map_id, so
we cannot reuse the exact structure. But make them similar, e.g.,
struct bpf_link_info {
/* common fields */
union {
struct { ... } raw_tracepoint;
struct { ... } tracing;
...
struct {
/* common fields for iter */
union {
struct {
__u32 map_id;
} map;
/* other structs for other targets */
};
};
};
};
so the structure is extensible the same way as bpf_iter_link_info.
Fixes: 6b0a249a30 ("bpf: Implement link_query for bpf iterators")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200828051922.758950-1-yhs@fb.com