[PATCHv5 6/7] tap: tap as an independent module

From: Sainath Grandhi
Date: Wed Feb 08 2017 - 16:38:28 EST


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

Signed-off-by: Sainath Grandhi <sainath.grandhi@xxxxxxxxx>
---
drivers/net/Kconfig | 7 +++++++
drivers/net/Makefile | 3 +--
drivers/net/{macvtap_main.c => macvtap.c} | 0
drivers/net/tap.c | 11 +++++++++++
drivers/vhost/Kconfig | 2 +-
include/linux/if_tap.h | 4 ++--
6 files changed, 22 insertions(+), 5 deletions(-)
rename drivers/net/{macvtap_main.c => macvtap.c} (100%)

diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 95c32f2..8f6d21b4 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -135,6 +135,7 @@ config MACVTAP
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
@@ -284,6 +285,12 @@ config 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"
default n
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 19b03a9..7dd86ca 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_PHYLIB) += phy/
obj-$(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
@@ -29,8 +30,6 @@ 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
#
diff --git a/drivers/net/macvtap_main.c b/drivers/net/macvtap.c
similarity index 100%
rename from drivers/net/macvtap_main.c
rename to drivers/net/macvtap.c
diff --git a/drivers/net/tap.c b/drivers/net/tap.c
index b7cdc90..a0ed508 100644
--- a/drivers/net/tap.c
+++ b/drivers/net/tap.c
@@ -312,6 +312,7 @@ void tap_del_queues(struct tap_dev *tap)
/* 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)
{
@@ -389,6 +390,7 @@ 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)
{
@@ -422,6 +424,7 @@ int tap_get_minor(dev_t major, struct tap_dev *tap)
mutex_unlock(&tap_major->minor_lock);
return retval < 0 ? retval : 0;
}
+EXPORT_SYMBOL_GPL(tap_get_minor);

void tap_free_minor(dev_t major, struct tap_dev *tap)
{
@@ -438,6 +441,7 @@ void tap_free_minor(dev_t major, struct tap_dev *tap)
}
mutex_unlock(&tap_major->minor_lock);
}
+EXPORT_SYMBOL_GPL(tap_free_minor);

static struct tap_dev *dev_get_by_tap_file(int major, int minor)
{
@@ -1193,6 +1197,7 @@ int tap_queue_resize(struct tap_dev *tap)
kfree(arrays);
return ret;
}
+EXPORT_SYMBOL_GPL(tap_queue_resize);

static int tap_list_add(dev_t major, const char *device_name)
{
@@ -1240,6 +1245,7 @@ int tap_create_cdev(struct cdev *tap_cdev,
out1:
return err;
}
+EXPORT_SYMBOL_GPL(tap_create_cdev);

void tap_destroy_cdev(dev_t major, struct cdev *tap_cdev)
{
@@ -1255,3 +1261,8 @@ void tap_destroy_cdev(dev_t major, struct cdev *tap_cdev)
list_del_rcu(&tap_major->next);
kfree_rcu(tap_major, rcu);
}
+EXPORT_SYMBOL_GPL(tap_destroy_cdev);
+
+MODULE_AUTHOR("Arnd Bergmann <arnd@xxxxxxxx>");
+MODULE_AUTHOR("Sainath Grandhi <sainath.grandhi@xxxxxxxxx>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/vhost/Kconfig b/drivers/vhost/Kconfig
index 40764ec..cfdecea 100644
--- a/drivers/vhost/Kconfig
+++ b/drivers/vhost/Kconfig
@@ -1,6 +1,6 @@
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
diff --git a/include/linux/if_tap.h b/include/linux/if_tap.h
index 362e71c..3482c3c 100644
--- a/include/linux/if_tap.h
+++ b/include/linux/if_tap.h
@@ -1,7 +1,7 @@
#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>
@@ -12,7 +12,7 @@ static inline struct socket *tap_get_socket(struct file *f)
{
return ERR_PTR(-EINVAL);
}
-#endif /* CONFIG_MACVTAP */
+#endif /* CONFIG_TAP */

#include <net/sock.h>
#include <linux/skb_array.h>
--
2.7.4