[GENETLINK]: Move command capabilities to flags.

This patch moves command capabilities to command flags. Other than
being cleaner, saves several bytes.
We increment the nlctrl version so as to signal to user space that
to not expect the attributes. We will try to be careful
not to do this too often ;->
Signed-off-by: NJamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/linux/genetlink.h

@@ -17,6 +17,9 @@ struct genlmsghdr {
 #define GENL_HDRLEN	NLMSG_ALIGN(sizeof(struct genlmsghdr))
 
 #define GENL_ADMIN_PERM		0x01
+#define GENL_CMD_CAP_DO		0x02
+#define GENL_CMD_CAP_DUMP	0x04
+#define GENL_CMD_CAP_HASPOL	0x08
 
 /*
  * List of reserved static generic netlink identifiers:
@@ -58,9 +61,6 @@ enum {
 	CTRL_ATTR_OP_UNSPEC,
 	CTRL_ATTR_OP_ID,
 	CTRL_ATTR_OP_FLAGS,
-	CTRL_ATTR_OP_POLICY,
-	CTRL_ATTR_OP_DOIT,
-	CTRL_ATTR_OP_DUMPIT,
 	__CTRL_ATTR_OP_MAX,
 };
 

net/netlink/genetlink.c

@@ -143,6 +143,13 @@ int genl_register_ops(struct genl_family *family, struct genl_ops *ops)
 		goto errout;
 	}
 
+	if (ops->dumpit)
+		ops->flags |= GENL_CMD_CAP_DO;
+	if (ops->doit)
+		ops->flags |= GENL_CMD_CAP_DUMP;
+	if (ops->policy)
+		ops->flags |= GENL_CMD_CAP_HASPOL;
+
 	genl_lock();
 	list_add_tail(&ops->ops_list, &family->ops_list);
 	genl_unlock();
@@ -387,7 +394,7 @@ static void genl_rcv(struct sock *sk, int len)
 static struct genl_family genl_ctrl = {
 	.id = GENL_ID_CTRL,
 	.name = "nlctrl",
-	.version = 0x1,
+	.version = 0x2,
 	.maxattr = CTRL_ATTR_MAX,
 };
 
@@ -425,15 +432,6 @@ static int ctrl_fill_info(struct genl_family *family, u32 pid, u32 seq,
 			NLA_PUT_U32(skb, CTRL_ATTR_OP_ID, ops->cmd);
 			NLA_PUT_U32(skb, CTRL_ATTR_OP_FLAGS, ops->flags);
 
-			if (ops->policy)
-				NLA_PUT_FLAG(skb, CTRL_ATTR_OP_POLICY);
-
-			if (ops->doit)
-				NLA_PUT_FLAG(skb, CTRL_ATTR_OP_DOIT);
-
-			if (ops->dumpit)
-				NLA_PUT_FLAG(skb, CTRL_ATTR_OP_DUMPIT);
-
 			nla_nest_end(skb, nest);
 		}