tap: tap as an independent module

This patch makes tap a separate module for other types of virtual interfaces, for example,
ipvlan to use.

Signed-off-by: Sainath Grandhi <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/Kconfig

···
 	tristate "MAC-VLAN based tap driver"
 	depends on MACVLAN
 	depends on INET
+	select TAP
 	help
 	  This adds a specialized tap character device driver that is based
 	  on the MAC-VLAN network interface, called macvtap. A macvtap device
···
 	  will be called tun.
 
 	  If you don't know what to use this for, you don't need it.
+
+config TAP
+	tristate
+	---help---
+	  This option is selected by any driver implementing tap user space
+	  interface for a virtual interface to re-use core tap functionality.
 
 config TUN_VNET_CROSS_LE
 	bool "Support for cross-endian vnet headers on little-endian kernels"

drivers/net/Makefile

···
 obj-$(CONFIG_RIONET) += rionet.o
 obj-$(CONFIG_NET_TEAM) += team/
 obj-$(CONFIG_TUN) += tun.o
+obj-$(CONFIG_TAP) += tap.o
 obj-$(CONFIG_VETH) += veth.o
 obj-$(CONFIG_VIRTIO_NET) += virtio_net.o
 obj-$(CONFIG_VXLAN) += vxlan.o
···
 obj-$(CONFIG_GTP) += gtp.o
 obj-$(CONFIG_NLMON) += nlmon.o
 obj-$(CONFIG_NET_VRF) += vrf.o
-
-macvtap-objs := macvtap_main.o tap.o
 
 #
 # Networking Drivers

drivers/net/tap.c

···
 	/* guarantee that any future tap_set_queue will fail */
 	tap->numvtaps = MAX_TAP_QUEUES;
 }
+EXPORT_SYMBOL_GPL(tap_del_queues);
 
 rx_handler_result_t tap_handle_frame(struct sk_buff **pskb)
 {
···
 	kfree_skb(skb);
 	return RX_HANDLER_CONSUMED;
 }
+EXPORT_SYMBOL_GPL(tap_handle_frame);
 
 static struct major_info *tap_get_major(int major)
 {
···
 	rcu_read_unlock();
 	return retval < 0 ? retval : 0;
 }
+EXPORT_SYMBOL_GPL(tap_get_minor);
 
 void tap_free_minor(dev_t major, struct tap_dev *tap)
 {
···
 unlock:
 	rcu_read_unlock();
 }
+EXPORT_SYMBOL_GPL(tap_free_minor);
 
 static struct tap_dev *dev_get_by_tap_file(int major, int minor)
 {
···
 	kfree(arrays);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(tap_queue_resize);
 
 static int tap_list_add(dev_t major, const char *device_name)
 {
···
 out1:
 	return err;
 }
+EXPORT_SYMBOL_GPL(tap_create_cdev);
 
 void tap_destroy_cdev(dev_t major, struct cdev *tap_cdev)
 {
···
 		}
 	}
 }
+EXPORT_SYMBOL_GPL(tap_destroy_cdev);
+
+MODULE_AUTHOR("Arnd Bergmann <[e-mail]>");
+MODULE_AUTHOR("Sainath Grandhi <[e-mail]>");
+MODULE_LICENSE("GPL");

drivers/vhost/Kconfig

···
 config VHOST_NET
 	tristate "Host kernel accelerator for virtio net"
-	depends on NET && EVENTFD && (TUN || !TUN) && (MACVTAP || !MACVTAP)
+	depends on NET && EVENTFD && (TUN || !TUN) && (TAP || !TAP)
 	select VHOST
 	---help---
 	  This kernel module can be loaded in host kernel to accelerate

include/linux/if_tap.h

···
 #ifndef _LINUX_IF_TAP_H_
 #define _LINUX_IF_TAP_H_
 
-#if IS_ENABLED(CONFIG_MACVTAP)
+#if IS_ENABLED(CONFIG_TAP)
 struct socket *tap_get_socket(struct file *);
 #else
 #include <linux/err.h>
···
 {
 	return ERR_PTR(-EINVAL);
 }
-#endif /* CONFIG_MACVTAP */
+#endif /* CONFIG_TAP */
 
 #include <net/sock.h>
 #include <linux/skb_array.h>