[PATCHv3 1/7] tap: Refactoring macvtap.c

[Sainath Grandhi]

macvtap module has code for tap/queue management and link management. This 
patch splits
the code into macvtap_main.c for link management and tap.c for tap/queue 
management.
Functionality in tap.c can be re-used for implementing tap on other virtual 
interfaces.

Signed-off-by: Sainath Grandhi 
---
 drivers/net/Makefile |   2 +
 drivers/net/macvtap_main.c   | 218 +++
 drivers/net/{macvtap.c => tap.c} | 204 ++--
 include/linux/if_macvtap.h   |  10 ++
 4 files changed, 238 insertions(+), 196 deletions(-)
 create mode 100644 drivers/net/macvtap_main.c
 rename drivers/net/{macvtap.c => tap.c} (84%)
 create mode 100644 include/linux/if_macvtap.h

diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 7336cbd..19b03a9 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -29,6 +29,8 @@ 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_main.c
new file mode 100644
index 000..96ffa60
--- /dev/null
+++ b/drivers/net/macvtap_main.c
@@ -0,0 +1,218 @@
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+#include 
+#include 
+#include 
+#include 
+#include 
+
+/*
+ * Variables for dealing with macvtaps device numbers.
+ */
+static dev_t macvtap_major;
+#define MACVTAP_NUM_DEVS (1U << MINORBITS)
+
+static const void *macvtap_net_namespace(struct device *d)
+{
+   struct net_device *dev = to_net_dev(d->parent);
+   return dev_net(dev);
+}
+
+static struct class macvtap_class = {
+   .name = "macvtap",
+   .owner = THIS_MODULE,
+   .ns_type = _ns_type_operations,
+   .namespace = macvtap_net_namespace,
+};
+static struct cdev macvtap_cdev;
+
+#define TUN_OFFLOADS (NETIF_F_HW_CSUM | NETIF_F_TSO_ECN | NETIF_F_TSO | \
+ NETIF_F_TSO6 | NETIF_F_UFO)
+
+static int macvtap_newlink(struct net *src_net,
+  struct net_device *dev,
+  struct nlattr *tb[],
+  struct nlattr *data[])
+{
+   struct macvlan_dev *vlan = netdev_priv(dev);
+   int err;
+
+   INIT_LIST_HEAD(>queue_list);
+
+   /* Since macvlan supports all offloads by default, make
+* tap support all offloads also.
+*/
+   vlan->tap_features = TUN_OFFLOADS;
+
+   err = netdev_rx_handler_register(dev, macvtap_handle_frame, vlan);
+   if (err)
+   return err;
+
+   /* Don't put anything that may fail after macvlan_common_newlink
+* because we can't undo what it does.
+*/
+   err = macvlan_common_newlink(src_net, dev, tb, data);
+   if (err) {
+   netdev_rx_handler_unregister(dev);
+   return err;
+   }
+
+   return 0;
+}
+
+static void macvtap_dellink(struct net_device *dev,
+   struct list_head *head)
+{
+   netdev_rx_handler_unregister(dev);
+   macvtap_del_queues(dev);
+   macvlan_dellink(dev, head);
+}
+
+static void macvtap_setup(struct net_device *dev)
+{
+   macvlan_common_setup(dev);
+   dev->tx_queue_len = TUN_READQ_SIZE;
+}
+
+static struct rtnl_link_ops macvtap_link_ops __read_mostly = {
+   .kind   = "macvtap",
+   .setup  = macvtap_setup,
+   .newlink= macvtap_newlink,
+   .dellink= macvtap_dellink,
+};
+
+static int macvtap_device_event(struct notifier_block *unused,
+   unsigned long event, void *ptr)
+{
+   struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+   struct macvlan_dev *vlan;
+   struct device *classdev;
+   dev_t devt;
+   int err;
+   char tap_name[IFNAMSIZ];
+
+   if (dev->rtnl_link_ops != _link_ops)
+   return NOTIFY_DONE;
+
+   snprintf(tap_name, IFNAMSIZ, "tap%d", dev->ifindex);
+   vlan = netdev_priv(dev);
+
+   switch (event) {
+   case NETDEV_REGISTER:
+   /* Create the device node here after the network device has
+* been registered but before register_netdevice has
+* finished running.
+*/
+   err = macvtap_get_minor(vlan);
+   if (err)
+   return notifier_from_errno(err);
+
+   devt = MKDEV(MAJOR(macvtap_major), vlan->minor);
+   classdev = device_create(_class, >dev, devt,
+dev, tap_name);
+   if (IS_ERR(classdev)) {
+   macvtap_free_minor(vlan);
+   return notifier_from_errno(PTR_ERR(classdev));
+   }
+   err = 

[PATCHv3 1/7] TAP: Refactoring macvtap.c

[Sainath Grandhi]

macvtap module has code for tap/queue management and link management. This 
patch splits
the code into macvtap_main.c for link management and tap.c for tap/queue 
management.
Functionality in tap.c can be re-used for implementing tap on other virtual 
interfaces.

Signed-off-by: Sainath Grandhi 
---
 drivers/net/Makefile |   2 +
 drivers/net/macvtap_main.c   | 218 +++
 drivers/net/{macvtap.c => tap.c} | 204 ++--
 include/linux/if_macvtap.h   |  10 ++
 4 files changed, 238 insertions(+), 196 deletions(-)
 create mode 100644 drivers/net/macvtap_main.c
 rename drivers/net/{macvtap.c => tap.c} (84%)
 create mode 100644 include/linux/if_macvtap.h

diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index 7336cbd..19b03a9 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -29,6 +29,8 @@ 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_main.c
new file mode 100644
index 000..96ffa60
--- /dev/null
+++ b/drivers/net/macvtap_main.c
@@ -0,0 +1,218 @@
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+#include 
+#include 
+#include 
+#include 
+#include 
+
+/*
+ * Variables for dealing with macvtaps device numbers.
+ */
+static dev_t macvtap_major;
+#define MACVTAP_NUM_DEVS (1U << MINORBITS)
+
+static const void *macvtap_net_namespace(struct device *d)
+{
+   struct net_device *dev = to_net_dev(d->parent);
+   return dev_net(dev);
+}
+
+static struct class macvtap_class = {
+   .name = "macvtap",
+   .owner = THIS_MODULE,
+   .ns_type = _ns_type_operations,
+   .namespace = macvtap_net_namespace,
+};
+static struct cdev macvtap_cdev;
+
+#define TUN_OFFLOADS (NETIF_F_HW_CSUM | NETIF_F_TSO_ECN | NETIF_F_TSO | \
+ NETIF_F_TSO6 | NETIF_F_UFO)
+
+static int macvtap_newlink(struct net *src_net,
+  struct net_device *dev,
+  struct nlattr *tb[],
+  struct nlattr *data[])
+{
+   struct macvlan_dev *vlan = netdev_priv(dev);
+   int err;
+
+   INIT_LIST_HEAD(>queue_list);
+
+   /* Since macvlan supports all offloads by default, make
+* tap support all offloads also.
+*/
+   vlan->tap_features = TUN_OFFLOADS;
+
+   err = netdev_rx_handler_register(dev, macvtap_handle_frame, vlan);
+   if (err)
+   return err;
+
+   /* Don't put anything that may fail after macvlan_common_newlink
+* because we can't undo what it does.
+*/
+   err = macvlan_common_newlink(src_net, dev, tb, data);
+   if (err) {
+   netdev_rx_handler_unregister(dev);
+   return err;
+   }
+
+   return 0;
+}
+
+static void macvtap_dellink(struct net_device *dev,
+   struct list_head *head)
+{
+   netdev_rx_handler_unregister(dev);
+   macvtap_del_queues(dev);
+   macvlan_dellink(dev, head);
+}
+
+static void macvtap_setup(struct net_device *dev)
+{
+   macvlan_common_setup(dev);
+   dev->tx_queue_len = TUN_READQ_SIZE;
+}
+
+static struct rtnl_link_ops macvtap_link_ops __read_mostly = {
+   .kind   = "macvtap",
+   .setup  = macvtap_setup,
+   .newlink= macvtap_newlink,
+   .dellink= macvtap_dellink,
+};
+
+static int macvtap_device_event(struct notifier_block *unused,
+   unsigned long event, void *ptr)
+{
+   struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+   struct macvlan_dev *vlan;
+   struct device *classdev;
+   dev_t devt;
+   int err;
+   char tap_name[IFNAMSIZ];
+
+   if (dev->rtnl_link_ops != _link_ops)
+   return NOTIFY_DONE;
+
+   snprintf(tap_name, IFNAMSIZ, "tap%d", dev->ifindex);
+   vlan = netdev_priv(dev);
+
+   switch (event) {
+   case NETDEV_REGISTER:
+   /* Create the device node here after the network device has
+* been registered but before register_netdevice has
+* finished running.
+*/
+   err = macvtap_get_minor(vlan);
+   if (err)
+   return notifier_from_errno(err);
+
+   devt = MKDEV(MAJOR(macvtap_major), vlan->minor);
+   classdev = device_create(_class, >dev, devt,
+dev, tap_name);
+   if (IS_ERR(classdev)) {
+   macvtap_free_minor(vlan);
+   return notifier_from_errno(PTR_ERR(classdev));
+   }
+   err =