bpf: Remove attach_type in bpf_netns_link

Use attach_type in bpf_link, and remove it in bpf_netns_link.
And move netns_type field to the end to fill the byte hole.

Signed-off-by: Tao Chen <chen.dylane@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20250710032038.888700-6-chen.dylane@linux.dev

diff --git a/kernel/bpf/net_namespace.c b/kernel/bpf/net_namespace.c
index 63702c8627573e510ed86d69afe4d90d63172148..8e88201c98bfed3ac77d5fd93fd2461a2facf30d 100644 (file)
--- a/kernel/bpf/net_namespace.c
+++ b/kernel/bpf/net_namespace.c
@@ -11,8 +11,6 @@
 
 struct bpf_netns_link {
        struct bpf_link link;
-       enum bpf_attach_type type;
-       enum netns_bpf_attach_type netns_type;
 
        /* We don't hold a ref to net in order to auto-detach the link
         * when netns is going away. Instead we rely on pernet
@@ -21,6 +19,7 @@ struct bpf_netns_link {
         */
        struct net *net;
        struct list_head node; /* node in list of links attached to net */
+       enum netns_bpf_attach_type netns_type;
 };
 
 /* Protects updates to netns_bpf */
@@ -216,7 +215,7 @@ static int bpf_netns_link_fill_info(const struct bpf_link *link,
        mutex_unlock(&netns_bpf_mutex);
 
        info->netns.netns_ino = inum;
-       info->netns.attach_type = net_link->type;
+       info->netns.attach_type = link->attach_type;
        return 0;
 }
 
@@ -230,7 +229,7 @@ static void bpf_netns_link_show_fdinfo(const struct bpf_link *link,
                   "netns_ino:\t%u\n"
                   "attach_type:\t%u\n",
                   info.netns.netns_ino,
-                  info.netns.attach_type);
+                  link->attach_type);
 }
 
 static const struct bpf_link_ops bpf_netns_link_ops = {
@@ -503,7 +502,6 @@ int netns_bpf_link_create(const union bpf_attr *attr, struct bpf_prog *prog)
        bpf_link_init(&net_link->link, BPF_LINK_TYPE_NETNS,
                      &bpf_netns_link_ops, prog, type);
        net_link->net = net;
-       net_link->type = type;
        net_link->netns_type = netns_type;
 
        err = bpf_link_prime(&net_link->link, &link_primer);