tap: Refactoring macvtap.c

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 <sainath.grandhi@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Sainath Grandhi 2017-02-10 16:03:46 -08:00 committed by David S. Miller
parent 35eeacf182
commit a8e0469873
4 changed files with 238 additions and 196 deletions

View File

@ -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
#

218
drivers/net/macvtap_main.c Normal file
View File

@ -0,0 +1,218 @@
#include <linux/etherdevice.h>
#include <linux/if_macvlan.h>
#include <linux/if_macvtap.h>
#include <linux/if_vlan.h>
#include <linux/interrupt.h>
#include <linux/nsproxy.h>
#include <linux/compat.h>
#include <linux/if_tun.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/cache.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/wait.h>
#include <linux/cdev.h>
#include <linux/idr.h>
#include <linux/fs.h>
#include <linux/uio.h>
#include <net/net_namespace.h>
#include <net/rtnetlink.h>
#include <net/sock.h>
#include <linux/virtio_net.h>
#include <linux/skb_array.h>
/*
* 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 = &net_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(&vlan->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 != &macvtap_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(&macvtap_class, &dev->dev, devt,
dev, tap_name);
if (IS_ERR(classdev)) {
macvtap_free_minor(vlan);
return notifier_from_errno(PTR_ERR(classdev));
}
err = sysfs_create_link(&dev->dev.kobj, &classdev->kobj,
tap_name);
if (err)
return notifier_from_errno(err);
break;
case NETDEV_UNREGISTER:
/* vlan->minor == 0 if NETDEV_REGISTER above failed */
if (vlan->minor == 0)
break;
sysfs_remove_link(&dev->dev.kobj, tap_name);
devt = MKDEV(MAJOR(macvtap_major), vlan->minor);
device_destroy(&macvtap_class, devt);
macvtap_free_minor(vlan);
break;
case NETDEV_CHANGE_TX_QUEUE_LEN:
if (macvtap_queue_resize(vlan))
return NOTIFY_BAD;
break;
}
return NOTIFY_DONE;
}
static struct notifier_block macvtap_notifier_block __read_mostly = {
.notifier_call = macvtap_device_event,
};
extern struct file_operations macvtap_fops;
static int macvtap_init(void)
{
int err;
err = alloc_chrdev_region(&macvtap_major, 0,
MACVTAP_NUM_DEVS, "macvtap");
if (err)
goto out1;
cdev_init(&macvtap_cdev, &macvtap_fops);
err = cdev_add(&macvtap_cdev, macvtap_major, MACVTAP_NUM_DEVS);
if (err)
goto out2;
err = class_register(&macvtap_class);
if (err)
goto out3;
err = register_netdevice_notifier(&macvtap_notifier_block);
if (err)
goto out4;
err = macvlan_link_register(&macvtap_link_ops);
if (err)
goto out5;
return 0;
out5:
unregister_netdevice_notifier(&macvtap_notifier_block);
out4:
class_unregister(&macvtap_class);
out3:
cdev_del(&macvtap_cdev);
out2:
unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
out1:
return err;
}
module_init(macvtap_init);
extern struct idr minor_idr;
static void macvtap_exit(void)
{
rtnl_link_unregister(&macvtap_link_ops);
unregister_netdevice_notifier(&macvtap_notifier_block);
class_unregister(&macvtap_class);
cdev_del(&macvtap_cdev);
unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
idr_destroy(&minor_idr);
}
module_exit(macvtap_exit);
MODULE_ALIAS_RTNL_LINK("macvtap");
MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
MODULE_LICENSE("GPL");

View File

@ -122,33 +122,14 @@ static struct proto macvtap_proto = {
.obj_size = sizeof (struct macvtap_queue),
};
/*
* Variables for dealing with macvtaps device numbers.
*/
static dev_t macvtap_major;
#define MACVTAP_NUM_DEVS (1U << MINORBITS)
static DEFINE_MUTEX(minor_lock);
static DEFINE_IDR(minor_idr);
DEFINE_IDR(minor_idr);
#define GOODCOPY_LEN 128
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 = &net_ns_type_operations,
.namespace = macvtap_net_namespace,
};
static struct cdev macvtap_cdev;
static const struct proto_ops macvtap_socket_ops;
#define TUN_OFFLOADS (NETIF_F_HW_CSUM | NETIF_F_TSO_ECN | NETIF_F_TSO | \
NETIF_F_TSO6 | NETIF_F_UFO)
#define RX_OFFLOADS (NETIF_F_GRO | NETIF_F_LRO)
#define TAP_FEATURES (NETIF_F_GSO | NETIF_F_SG | NETIF_F_FRAGLIST)
@ -332,7 +313,7 @@ out:
* that it holds on all queues and safely set the pointer
* from the queues to NULL.
*/
static void macvtap_del_queues(struct net_device *dev)
void macvtap_del_queues(struct net_device *dev)
{
struct macvlan_dev *vlan = netdev_priv(dev);
struct macvtap_queue *q, *tmp;
@ -352,7 +333,7 @@ static void macvtap_del_queues(struct net_device *dev)
vlan->numvtaps = MAX_MACVTAP_QUEUES;
}
static rx_handler_result_t macvtap_handle_frame(struct sk_buff **pskb)
rx_handler_result_t macvtap_handle_frame(struct sk_buff **pskb)
{
struct sk_buff *skb = *pskb;
struct net_device *dev = skb->dev;
@ -407,7 +388,7 @@ static rx_handler_result_t macvtap_handle_frame(struct sk_buff **pskb)
/* If we receive a partial checksum and the tap side
* doesn't support checksum offload, compute the checksum.
* Note: it doesn't matter which checksum feature to
* check, we either support them all or none.
* check, we either support them all or none.
*/
if (skb->ip_summed == CHECKSUM_PARTIAL &&
!(features & NETIF_F_CSUM_MASK) &&
@ -428,7 +409,7 @@ drop:
return RX_HANDLER_CONSUMED;
}
static int macvtap_get_minor(struct macvlan_dev *vlan)
int macvtap_get_minor(struct macvlan_dev *vlan)
{
int retval = -ENOMEM;
@ -444,7 +425,7 @@ static int macvtap_get_minor(struct macvlan_dev *vlan)
return retval < 0 ? retval : 0;
}
static void macvtap_free_minor(struct macvlan_dev *vlan)
void macvtap_free_minor(struct macvlan_dev *vlan)
{
mutex_lock(&minor_lock);
if (vlan->minor) {
@ -469,59 +450,6 @@ static struct net_device *dev_get_by_macvtap_minor(int minor)
return dev;
}
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(&vlan->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 void macvtap_sock_write_space(struct sock *sk)
{
wait_queue_head_t *wqueue;
@ -1169,7 +1097,7 @@ static long macvtap_compat_ioctl(struct file *file, unsigned int cmd,
}
#endif
static const struct file_operations macvtap_fops = {
const struct file_operations macvtap_fops = {
.owner = THIS_MODULE,
.open = macvtap_open,
.release = macvtap_release,
@ -1235,7 +1163,7 @@ struct socket *macvtap_get_socket(struct file *file)
}
EXPORT_SYMBOL_GPL(macvtap_get_socket);
static int macvtap_queue_resize(struct macvlan_dev *vlan)
int macvtap_queue_resize(struct macvlan_dev *vlan)
{
struct net_device *dev = vlan->dev;
struct macvtap_queue *q;
@ -1256,119 +1184,3 @@ static int macvtap_queue_resize(struct macvlan_dev *vlan)
kfree(arrays);
return ret;
}
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 != &macvtap_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(&macvtap_class, &dev->dev, devt,
dev, tap_name);
if (IS_ERR(classdev)) {
macvtap_free_minor(vlan);
return notifier_from_errno(PTR_ERR(classdev));
}
err = sysfs_create_link(&dev->dev.kobj, &classdev->kobj,
tap_name);
if (err)
return notifier_from_errno(err);
break;
case NETDEV_UNREGISTER:
/* vlan->minor == 0 if NETDEV_REGISTER above failed */
if (vlan->minor == 0)
break;
sysfs_remove_link(&dev->dev.kobj, tap_name);
devt = MKDEV(MAJOR(macvtap_major), vlan->minor);
device_destroy(&macvtap_class, devt);
macvtap_free_minor(vlan);
break;
case NETDEV_CHANGE_TX_QUEUE_LEN:
if (macvtap_queue_resize(vlan))
return NOTIFY_BAD;
break;
}
return NOTIFY_DONE;
}
static struct notifier_block macvtap_notifier_block __read_mostly = {
.notifier_call = macvtap_device_event,
};
static int macvtap_init(void)
{
int err;
err = alloc_chrdev_region(&macvtap_major, 0,
MACVTAP_NUM_DEVS, "macvtap");
if (err)
goto out1;
cdev_init(&macvtap_cdev, &macvtap_fops);
err = cdev_add(&macvtap_cdev, macvtap_major, MACVTAP_NUM_DEVS);
if (err)
goto out2;
err = class_register(&macvtap_class);
if (err)
goto out3;
err = register_netdevice_notifier(&macvtap_notifier_block);
if (err)
goto out4;
err = macvlan_link_register(&macvtap_link_ops);
if (err)
goto out5;
return 0;
out5:
unregister_netdevice_notifier(&macvtap_notifier_block);
out4:
class_unregister(&macvtap_class);
out3:
cdev_del(&macvtap_cdev);
out2:
unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
out1:
return err;
}
module_init(macvtap_init);
static void macvtap_exit(void)
{
rtnl_link_unregister(&macvtap_link_ops);
unregister_netdevice_notifier(&macvtap_notifier_block);
class_unregister(&macvtap_class);
cdev_del(&macvtap_cdev);
unregister_chrdev_region(macvtap_major, MACVTAP_NUM_DEVS);
idr_destroy(&minor_idr);
}
module_exit(macvtap_exit);
MODULE_ALIAS_RTNL_LINK("macvtap");
MODULE_AUTHOR("Arnd Bergmann <arnd@arndb.de>");
MODULE_LICENSE("GPL");

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@ -0,0 +1,10 @@
#ifndef _LINUX_IF_MACVTAP_H_
#define _LINUX_IF_MACVTAP_H_
rx_handler_result_t macvtap_handle_frame(struct sk_buff **pskb);
void macvtap_del_queues(struct net_device *dev);
int macvtap_get_minor(struct macvlan_dev *vlan);
void macvtap_free_minor(struct macvlan_dev *vlan);
int macvtap_queue_resize(struct macvlan_dev *vlan);
#endif /*_LINUX_IF_MACVTAP_H_*/