LXR linux/drivers/hv/hv_utils

   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 * Kernel/userspace transport abstraction for Hyper-V util driver.
   4 *
   5 * Copyright (C) 2015, Vitaly Kuznetsov <vkuznets@redhat.com>
   6 */
   7
   8#ifndef _HV_UTILS_TRANSPORT_H
   9#define _HV_UTILS_TRANSPORT_H
  10
  11#include <linux/connector.h>
  12#include <linux/miscdevice.h>
  13
  14enum hvutil_transport_mode {
  15        HVUTIL_TRANSPORT_INIT = 0,
  16        HVUTIL_TRANSPORT_NETLINK,
  17        HVUTIL_TRANSPORT_CHARDEV,
  18        HVUTIL_TRANSPORT_DESTROY,
  19};
  20
  21struct hvutil_transport {
  22        int mode;                           /* hvutil_transport_mode */
  23        struct file_operations fops;        /* file operations */
  24        struct miscdevice mdev;             /* misc device */
  25        struct cb_id cn_id;                 /* CN_*_IDX/CN_*_VAL */
  26        struct list_head list;              /* hvt_list */
  27        int (*on_msg)(void *, int);         /* callback on new user message */
  28        void (*on_reset)(void);             /* callback when userspace drops */
  29        void (*on_read)(void);              /* callback on message read */
  30        u8 *outmsg;                         /* message to the userspace */
  31        int outmsg_len;                     /* its length */
  32        wait_queue_head_t outmsg_q;         /* poll/read wait queue */
  33        struct mutex lock;                  /* protects struct members */
  34        struct completion release;          /* synchronize with fd release */
  35};
  36
  37struct hvutil_transport *hvutil_transport_init(const char *name,
  38                                               u32 cn_idx, u32 cn_val,
  39                                               int (*on_msg)(void *, int),
  40                                               void (*on_reset)(void));
  41int hvutil_transport_send(struct hvutil_transport *hvt, void *msg, int len,
  42                          void (*on_read_cb)(void));
  43void hvutil_transport_destroy(struct hvutil_transport *hvt);
  44
  45#endif /* _HV_UTILS_TRANSPORT_H */
  46