tools: libbpf: allow setting ifindex for programs and maps

Users of bpf_object__open()/bpf_object__load() APIs may want to
load the programs and maps onto a device for offload.  Allow
setting ifindex on those sub-objects.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

tools/lib/bpf/libbpf.c

@@ -1896,6 +1896,11 @@ void *bpf_program__priv(struct bpf_program *prog)
 	return prog ? prog->priv : ERR_PTR(-EINVAL);
 }
 
+void bpf_program__set_ifindex(struct bpf_program *prog, __u32 ifindex)
+{
+	prog->prog_ifindex = ifindex;
+}
+
 const char *bpf_program__title(struct bpf_program *prog, bool needs_copy)
 {
 	const char *title;
@@ -2122,6 +2127,11 @@ void *bpf_map__priv(struct bpf_map *map)
 	return map ? map->priv : ERR_PTR(-EINVAL);
 }
 
+void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex)
+{
+	map->map_ifindex = ifindex;
+}
+
 struct bpf_map *
 bpf_map__next(struct bpf_map *prev, struct bpf_object *obj)
 {

tools/lib/bpf/libbpf.h

@@ -109,6 +109,7 @@ int bpf_program__set_priv(struct bpf_program *prog, void *priv,
 			  bpf_program_clear_priv_t clear_priv);
 
 void *bpf_program__priv(struct bpf_program *prog);
+void bpf_program__set_ifindex(struct bpf_program *prog, __u32 ifindex);
 
 const char *bpf_program__title(struct bpf_program *prog, bool needs_copy);
 
@@ -251,6 +252,7 @@ typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *);
 int bpf_map__set_priv(struct bpf_map *map, void *priv,
 		      bpf_map_clear_priv_t clear_priv);
 void *bpf_map__priv(struct bpf_map *map);
+void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
 int bpf_map__pin(struct bpf_map *map, const char *path);
 
 long libbpf_get_error(const void *ptr);