bpf: revert report offload info to user space

This reverts commit bd601b6ada ("bpf: report offload info to user
space").  The ifindex by itself is not sufficient, we should provide
information on which network namespace this ifindex belongs to.
After considering some options we concluded that it's best to just
remove this API for now, and rework it in -next.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

include/linux/bpf.h

@@ -515,7 +515,6 @@ static inline struct bpf_prog *bpf_prog_get_type(u32 ufd,
 
 int bpf_prog_offload_compile(struct bpf_prog *prog);
 void bpf_prog_offload_destroy(struct bpf_prog *prog);
-u32 bpf_prog_offload_ifindex(struct bpf_prog *prog);
 
 #if defined(CONFIG_NET) && defined(CONFIG_BPF_SYSCALL)
 int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr);

include/uapi/linux/bpf.h

@@ -897,10 +897,6 @@ enum sk_action {
 
 #define BPF_TAG_SIZE	8
 
-enum bpf_prog_status {
-	BPF_PROG_STATUS_DEV_BOUND	= (1 << 0),
-};
-
 struct bpf_prog_info {
 	__u32 type;
 	__u32 id;
@@ -914,8 +910,6 @@ struct bpf_prog_info {
 	__u32 nr_map_ids;
 	__aligned_u64 map_ids;
 	char name[BPF_OBJ_NAME_LEN];
-	__u32 ifindex;
-	__u32 status;
 } __attribute__((aligned(8)));
 
 struct bpf_map_info {

kernel/bpf/offload.c

@@ -149,18 +149,6 @@ int bpf_prog_offload_compile(struct bpf_prog *prog)
 	return bpf_prog_offload_translate(prog);
 }
 
-u32 bpf_prog_offload_ifindex(struct bpf_prog *prog)
-{
-	struct bpf_dev_offload *offload = prog->aux->offload;
-	u32 ifindex;
-
-	rtnl_lock();
-	ifindex = offload->netdev ? offload->netdev->ifindex : 0;
-	rtnl_unlock();
-
-	return ifindex;
-}
-
 const struct bpf_prog_ops bpf_offload_prog_ops = {
 };
 

kernel/bpf/syscall.c

@@ -1616,11 +1616,6 @@ static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
 			return -EFAULT;
 	}
 
-	if (bpf_prog_is_dev_bound(prog->aux)) {
-		info.status |= BPF_PROG_STATUS_DEV_BOUND;
-		info.ifindex = bpf_prog_offload_ifindex(prog);
-	}
-
 done:
 	if (copy_to_user(uinfo, &info, info_len) ||
 	    put_user(info_len, &uattr->info.info_len))