drivers/hv/hv_utils_transport.h

   1 /*
   2  * Kernel/userspace transport abstraction for Hyper-V util driver.
   3  *
   4  * Copyright (C) 2015, Vitaly Kuznetsov <vkuznets@redhat.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 as published
   8  * by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  13  * NON INFRINGEMENT.  See the GNU General Public License for more
  14  * details.
  15  *
  16  */
  17
  18 #ifndef _HV_UTILS_TRANSPORT_H
  19 #define _HV_UTILS_TRANSPORT_H
  20
  21 #include <linux/connector.h>
  22 #include <linux/miscdevice.h>
  23
  24 enum hvutil_transport_mode {
  25         HVUTIL_TRANSPORT_INIT = 0,
  26         HVUTIL_TRANSPORT_NETLINK,
  27         HVUTIL_TRANSPORT_CHARDEV,
  28         HVUTIL_TRANSPORT_DESTROY,
  29 };
  30
  31 struct hvutil_transport {
  32         int mode;                           /* hvutil_transport_mode */
  33         struct file_operations fops;        /* file operations */
  34         struct miscdevice mdev;             /* misc device */
  35         struct cb_id cn_id;                 /* CN_*_IDX/CN_*_VAL */
  36         struct list_head list;              /* hvt_list */
  37         int (*on_msg)(void *, int);         /* callback on new user message */
  38         void (*on_reset)(void);             /* callback when userspace drops */
  39         void (*on_read)(void);              /* callback on message read */
  40         u8 *outmsg;                         /* message to the userspace */
  41         int outmsg_len;                     /* its length */
  42         wait_queue_head_t outmsg_q;         /* poll/read wait queue */
  43         struct mutex lock;                  /* protects struct members */
  44         struct completion release;          /* synchronize with fd release */
  45 };
  46
  47 struct hvutil_transport *hvutil_transport_init(const char *name,
  48                                                u32 cn_idx, u32 cn_val,
  49                                                int (*on_msg)(void *, int),
  50                                                void (*on_reset)(void));
  51 int hvutil_transport_send(struct hvutil_transport *hvt, void *msg, int len,
  52                           void (*on_read_cb)(void));
  53 void hvutil_transport_destroy(struct hvutil_transport *hvt);
  54
  55 #endif /* _HV_UTILS_TRANSPORT_H */