netlink: add netlink_kernel_cfg parameter to netlink_kernel_create

This patch adds the following structure:

struct netlink_kernel_cfg {
        unsigned int    groups;
        void            (*input)(struct sk_buff *skb);
        struct mutex    *cb_mutex;
};

That can be passed to netlink_kernel_create to set optional configurations
for netlink kernel sockets.

I've populated this structure by looking for NULL and zero parameters at the
existing code. The remaining parameters that always need to be set are still
left in the original interface.

That includes optional parameters for the netlink socket creation. This allows
easy extensibility of this interface in the future.

This patch also adapts all callers to use this new interface.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 29 insertions, 13 deletions

diff --git a/drivers/connector/connector.c b/drivers/connector/connector.c
index 34e0e9e..116cf8d 100644
--- a/drivers/connector/connector.c
+++ b/drivers/connector/connector.c
@@ -251,15 +251,20 @@ static const struct file_operations cn_file_ops = {
 	.release = single_release
 };
 
+static struct cn_dev cdev = {
+	.input   = cn_rx_skb,
+};
+
 static int __devinit cn_init(void)
 {
 	struct cn_dev *dev = &cdev;
-
-	dev->input = cn_rx_skb;
+	struct netlink_kernel_cfg cfg = {
+		.groups	= CN_NETLINK_USERS + 0xf,
+		.input	= dev->input,
+	};
 
 	dev->nls = netlink_kernel_create(&init_net, NETLINK_CONNECTOR,
-					 CN_NETLINK_USERS + 0xf,
-					 dev->input, NULL, THIS_MODULE);
+					 THIS_MODULE, &cfg);
 	if (!dev->nls)
 		return -EIO;
 
diff --git a/drivers/infiniband/core/netlink.c b/drivers/infiniband/core/netlink.c
index 1e691dc..3ae2bfd 100644
--- a/drivers/infiniband/core/netlink.c
+++ b/drivers/infiniband/core/netlink.c
@@ -173,8 +173,11 @@ static void ibnl_rcv(struct sk_buff *skb)
 
 int __init ibnl_init(void)
 {
-	nls = netlink_kernel_create(&init_net, NETLINK_RDMA, 0, ibnl_rcv,
-				    NULL, THIS_MODULE);
+	struct netlink_kernel_cfg cfg = {
+		.input	= ibnl_rcv,
+	};
+
+	nls = netlink_kernel_create(&init_net, NETLINK_RDMA, THIS_MODULE, &cfg);
 	if (!nls) {
 		pr_warn("Failed to create netlink socket\n");
 		return -ENOMEM;
diff --git a/drivers/scsi/scsi_netlink.c b/drivers/scsi/scsi_netlink.c
index c77628a..8818dd6 100644
--- a/drivers/scsi/scsi_netlink.c
+++ b/drivers/scsi/scsi_netlink.c
@@ -486,6 +486,10 @@ void
 scsi_netlink_init(void)
 {
 	int error;
+	struct netlink_kernel_cfg cfg = {
+		.input	= scsi_nl_rcv_msg,
+		.groups	= SCSI_NL_GRP_CNT,
+	};
 
 	INIT_LIST_HEAD(&scsi_nl_drivers);
 
@@ -497,8 +501,7 @@ scsi_netlink_init(void)
 	}
 
 	scsi_nl_sock = netlink_kernel_create(&init_net, NETLINK_SCSITRANSPORT,
-				SCSI_NL_GRP_CNT, scsi_nl_rcv_msg, NULL,
-				THIS_MODULE);
+					     THIS_MODULE, &cfg);
 	if (!scsi_nl_sock) {
 		printk(KERN_ERR "%s: register of receive handler failed\n",
 				__func__);
diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 1cf640e..6042954 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -2936,7 +2936,10 @@ EXPORT_SYMBOL_GPL(iscsi_unregister_transport);
 static __init int iscsi_transport_init(void)
 {
 	int err;
-
+	struct netlink_kernel_cfg cfg = {
+		.groups	= 1,
+		.input	= iscsi_if_rx,
+	};
 	printk(KERN_INFO "Loading iSCSI transport class v%s.\n",
 		ISCSI_TRANSPORT_VERSION);
 
@@ -2966,8 +2969,8 @@ static __init int iscsi_transport_init(void)
 	if (err)
 		goto unregister_conn_class;
 
-	nls = netlink_kernel_create(&init_net, NETLINK_ISCSI, 1, iscsi_if_rx,
-				    NULL, THIS_MODULE);
+	nls = netlink_kernel_create(&init_net, NETLINK_ISCSI,
+				    THIS_MODULE, &cfg);
 	if (!nls) {
 		err = -ENOBUFS;
 		goto unregister_session_class;
diff --git a/drivers/staging/gdm72xx/netlink_k.c b/drivers/staging/gdm72xx/netlink_k.c
index 2489bb5..87c3a07 100644
--- a/drivers/staging/gdm72xx/netlink_k.c
+++ b/drivers/staging/gdm72xx/netlink_k.c
@@ -88,13 +88,15 @@ struct sock *netlink_init(int unit, void (*cb)(struct net_device *dev, u16 type,
 						void *msg, int len))
 {
 	struct sock *sock;
+	struct netlink_kernel_cfg cfg = {
+		.input  = netlink_rcv,
+	};
 
 #if !defined(DEFINE_MUTEX)
 	init_MUTEX(&netlink_mutex);
 #endif
 
-	sock = netlink_kernel_create(&init_net, unit, 0, netlink_rcv, NULL,
-					THIS_MODULE);
+	sock = netlink_kernel_create(&init_net, unit, THIS_MODULE, &cfg);
 
 	if (sock)
 		rcv_cb = cb;