sock_diag: add module pointer to "struct sock_diag_handler"

Following patch is going to use RCU instead of
sock_diag_table_mutex acquisition.

This patch is a preparation, no change of behavior yet.

Signed-off-by: Eric Dumazet <[e-mail]>
Reviewed-by: Guillaume Nault <[e-mail]>
Reviewed-by: Kuniyuki Iwashima <[e-mail]>
Reviewed-by: Willem de Bruijn <[e-mail]>
Signed-off-by: Paolo Abeni <[e-mail]>

include/linux/sock_diag.h

···
 struct sock;
 
 struct sock_diag_handler {
+	struct module *owner;
 	__u8 family;
 	int (*dump)(struct sk_buff *skb, struct nlmsghdr *nlh);
 	int (*get_info)(struct sk_buff *skb, struct sock *sk);

net/ipv4/inet_diag.c

···
 }
 
 static const struct sock_diag_handler inet_diag_handler = {
+	.owner = THIS_MODULE,
 	.family = AF_INET,
 	.dump = inet_diag_handler_cmd,
 	.get_info = inet_diag_handler_get_info,
···
 };
 
 static const struct sock_diag_handler inet6_diag_handler = {
+	.owner = THIS_MODULE,
 	.family = AF_INET6,
 	.dump = inet_diag_handler_cmd,
 	.get_info = inet_diag_handler_get_info,

net/netlink/diag.c

···
 }
 
 static const struct sock_diag_handler netlink_diag_handler = {
+	.owner = THIS_MODULE,
 	.family = AF_NETLINK,
 	.dump = netlink_diag_handler_dump,
 };

net/packet/diag.c

···
 }
 
 static const struct sock_diag_handler packet_diag_handler = {
+	.owner = THIS_MODULE,
 	.family = AF_PACKET,
 	.dump = packet_diag_handler_dump,
 };

net/smc/smc_diag.c

···
 }
 
 static const struct sock_diag_handler smc_diag_handler = {
+	.owner = THIS_MODULE,
 	.family = AF_SMC,
 	.dump = smc_diag_handler_dump,
 };

net/tipc/diag.c

···
 }
 
 static const struct sock_diag_handler tipc_sock_diag_handler = {
+	.owner = THIS_MODULE,
 	.family = AF_TIPC,
 	.dump = tipc_sock_diag_handler_dump,
 };

net/unix/diag.c

···
 }
 
 static const struct sock_diag_handler unix_diag_handler = {
+	.owner = THIS_MODULE,
 	.family = AF_UNIX,
 	.dump = unix_diag_handler_dump,
 };

net/vmw_vsock/diag.c

···
 }
 
 static const struct sock_diag_handler vsock_diag_handler = {
+	.owner = THIS_MODULE,
 	.family = AF_VSOCK,
 	.dump = vsock_diag_handler_dump,
 };

net/xdp/xsk_diag.c

···
 }
 
 static const struct sock_diag_handler xsk_diag_handler = {
+	.owner = THIS_MODULE,
 	.family = AF_XDP,
 	.dump = xsk_diag_handler_dump,
 };