LXR qemu/include/hw/virtio/vhost-user.h

   1/*
   2 * Copyright (c) 2017-2018 Intel Corporation
   3 *
   4 * This work is licensed under the terms of the GNU GPL, version 2.
   5 * See the COPYING file in the top-level directory.
   6 */
   7
   8#ifndef HW_VIRTIO_VHOST_USER_H
   9#define HW_VIRTIO_VHOST_USER_H
  10
  11#include "chardev/char-fe.h"
  12#include "hw/virtio/virtio.h"
  13
  14/**
  15 * VhostUserHostNotifier - notifier information for one queue
  16 * @rcu: rcu_head for cleanup
  17 * @mr: memory region of notifier
  18 * @addr: current mapped address
  19 * @unmap_addr: address to be un-mapped
  20 * @idx: virtioqueue index
  21 *
  22 * The VhostUserHostNotifier entries are re-used. When an old mapping
  23 * is to be released it is moved to @unmap_addr and @addr is replaced.
  24 * Once the RCU process has completed the unmap @unmap_addr is
  25 * cleared.
  26 */
  27typedef struct VhostUserHostNotifier {
  28    struct rcu_head rcu;
  29    MemoryRegion mr;
  30    void *addr;
  31    void *unmap_addr;
  32    int idx;
  33} VhostUserHostNotifier;
  34
  35/**
  36 * VhostUserState - shared state for all vhost-user devices
  37 * @chr: the character backend for the socket
  38 * @notifiers: GPtrArray of @VhostUserHostnotifier
  39 * @memory_slots:
  40 */
  41typedef struct VhostUserState {
  42    CharBackend *chr;
  43    GPtrArray *notifiers;
  44    int memory_slots;
  45    bool supports_config;
  46} VhostUserState;
  47
  48/**
  49 * vhost_user_init() - initialise shared vhost_user state
  50 * @user: allocated area for storing shared state
  51 * @chr: the chardev for the vhost socket
  52 * @errp: error handle
  53 *
  54 * User can either directly g_new() space for the state or embed
  55 * VhostUserState in their larger device structure and just point to
  56 * it.
  57 *
  58 * Return: true on success, false on error while setting errp.
  59 */
  60bool vhost_user_init(VhostUserState *user, CharBackend *chr, Error **errp);
  61
  62/**
  63 * vhost_user_cleanup() - cleanup state
  64 * @user: ptr to use state
  65 *
  66 * Cleans up shared state and notifiers, callee is responsible for
  67 * freeing the @VhostUserState memory itself.
  68 */
  69void vhost_user_cleanup(VhostUserState *user);
  70
  71/**
  72 * vhost_user_async_close() - cleanup vhost-user post connection drop
  73 * @d: DeviceState for the associated device (passed to callback)
  74 * @chardev: the CharBackend associated with the connection
  75 * @vhost: the common vhost device
  76 * @cb: the user callback function to complete the clean-up
  77 *
  78 * This function is used to handle the shutdown of a vhost-user
  79 * connection to a backend. We handle this centrally to make sure we
  80 * do all the steps and handle potential races due to VM shutdowns.
  81 * Once the connection is disabled we call a backhalf to ensure
  82 */
  83typedef void (*vu_async_close_fn)(DeviceState *cb);
  84
  85void vhost_user_async_close(DeviceState *d,
  86                            CharBackend *chardev, struct vhost_dev *vhost,
  87                            vu_async_close_fn cb);
  88
  89#endif
  90