include/linux/if_tap.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _LINUX_IF_TAP_H_
   3 #define _LINUX_IF_TAP_H_
   4
   5 #if IS_ENABLED(CONFIG_TAP)
   6 struct socket *tap_get_socket(struct file *);
   7 struct skb_array *tap_get_skb_array(struct file *file);
   8 #else
   9 #include <linux/err.h>
  10 #include <linux/errno.h>
  11 struct file;
  12 struct socket;
  13 static inline struct socket *tap_get_socket(struct file *f)
  14 {
  15         return ERR_PTR(-EINVAL);
  16 }
  17 static inline struct skb_array *tap_get_skb_array(struct file *f)
  18 {
  19         return ERR_PTR(-EINVAL);
  20 }
  21 #endif /* CONFIG_TAP */
  22
  23 #include <net/sock.h>
  24 #include <linux/skb_array.h>
  25
  26 #define MAX_TAP_QUEUES 256
  27
  28 struct tap_queue;
  29
  30 struct tap_dev {
  31         struct net_device       *dev;
  32         u16                     flags;
  33         /* This array tracks active taps. */
  34         struct tap_queue    __rcu *taps[MAX_TAP_QUEUES];
  35         /* This list tracks all taps (both enabled and disabled) */
  36         struct list_head        queue_list;
  37         int                     numvtaps;
  38         int                     numqueues;
  39         netdev_features_t       tap_features;
  40         int                     minor;
  41
  42         void (*update_features)(struct tap_dev *tap, netdev_features_t features);
  43         void (*count_tx_dropped)(struct tap_dev *tap);
  44         void (*count_rx_dropped)(struct tap_dev *tap);
  45 };
  46
  47 /*
  48  * A tap queue is the central object of tap module, it connects
  49  * an open character device to virtual interface. There can be
  50  * multiple queues on one interface, which map back to queues
  51  * implemented in hardware on the underlying device.
  52  *
  53  * tap_proto is used to allocate queues through the sock allocation
  54  * mechanism.
  55  *
  56  */
  57
  58 struct tap_queue {
  59         struct sock sk;
  60         struct socket sock;
  61         struct socket_wq wq;
  62         int vnet_hdr_sz;
  63         struct tap_dev __rcu *tap;
  64         struct file *file;
  65         unsigned int flags;
  66         u16 queue_index;
  67         bool enabled;
  68         struct list_head next;
  69         struct skb_array skb_array;
  70 };
  71
  72 rx_handler_result_t tap_handle_frame(struct sk_buff **pskb);
  73 void tap_del_queues(struct tap_dev *tap);
  74 int tap_get_minor(dev_t major, struct tap_dev *tap);
  75 void tap_free_minor(dev_t major, struct tap_dev *tap);
  76 int tap_queue_resize(struct tap_dev *tap);
  77 int tap_create_cdev(struct cdev *tap_cdev, dev_t *tap_major,
  78                     const char *device_name, struct module *module);
  79 void tap_destroy_cdev(dev_t major, struct cdev *tap_cdev);
  80
  81 #endif /*_LINUX_IF_TAP_H_*/