qemu/include/hw/virtio/vhost-user.h
Hanna Czenczek cda83adc62 vhost-user: Interface for migration state transfer
Add the interface for transferring the back-end's state during migration
as defined previously in vhost-user.rst.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20231016134243.68248-6-hreitz@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2023-11-07 03:39:10 -05:00

115 lines
3.7 KiB
C

/*
* Copyright (c) 2017-2018 Intel Corporation
*
* This work is licensed under the terms of the GNU GPL, version 2.
* See the COPYING file in the top-level directory.
*/
#ifndef HW_VIRTIO_VHOST_USER_H
#define HW_VIRTIO_VHOST_USER_H
#include "chardev/char-fe.h"
#include "hw/virtio/virtio.h"
enum VhostUserProtocolFeature {
VHOST_USER_PROTOCOL_F_MQ = 0,
VHOST_USER_PROTOCOL_F_LOG_SHMFD = 1,
VHOST_USER_PROTOCOL_F_RARP = 2,
VHOST_USER_PROTOCOL_F_REPLY_ACK = 3,
VHOST_USER_PROTOCOL_F_NET_MTU = 4,
VHOST_USER_PROTOCOL_F_BACKEND_REQ = 5,
VHOST_USER_PROTOCOL_F_CROSS_ENDIAN = 6,
VHOST_USER_PROTOCOL_F_CRYPTO_SESSION = 7,
VHOST_USER_PROTOCOL_F_PAGEFAULT = 8,
VHOST_USER_PROTOCOL_F_CONFIG = 9,
VHOST_USER_PROTOCOL_F_BACKEND_SEND_FD = 10,
VHOST_USER_PROTOCOL_F_HOST_NOTIFIER = 11,
VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD = 12,
VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13,
VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS = 14,
VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS = 15,
VHOST_USER_PROTOCOL_F_STATUS = 16,
/* Feature 17 reserved for VHOST_USER_PROTOCOL_F_XEN_MMAP. */
VHOST_USER_PROTOCOL_F_SHARED_OBJECT = 18,
VHOST_USER_PROTOCOL_F_DEVICE_STATE = 19,
VHOST_USER_PROTOCOL_F_MAX
};
/**
* VhostUserHostNotifier - notifier information for one queue
* @rcu: rcu_head for cleanup
* @mr: memory region of notifier
* @addr: current mapped address
* @unmap_addr: address to be un-mapped
* @idx: virtioqueue index
*
* The VhostUserHostNotifier entries are re-used. When an old mapping
* is to be released it is moved to @unmap_addr and @addr is replaced.
* Once the RCU process has completed the unmap @unmap_addr is
* cleared.
*/
typedef struct VhostUserHostNotifier {
struct rcu_head rcu;
MemoryRegion mr;
void *addr;
void *unmap_addr;
int idx;
} VhostUserHostNotifier;
/**
* VhostUserState - shared state for all vhost-user devices
* @chr: the character backend for the socket
* @notifiers: GPtrArray of @VhostUserHostnotifier
* @memory_slots:
*/
typedef struct VhostUserState {
CharBackend *chr;
GPtrArray *notifiers;
int memory_slots;
bool supports_config;
} VhostUserState;
/**
* vhost_user_init() - initialise shared vhost_user state
* @user: allocated area for storing shared state
* @chr: the chardev for the vhost socket
* @errp: error handle
*
* User can either directly g_new() space for the state or embed
* VhostUserState in their larger device structure and just point to
* it.
*
* Return: true on success, false on error while setting errp.
*/
bool vhost_user_init(VhostUserState *user, CharBackend *chr, Error **errp);
/**
* vhost_user_cleanup() - cleanup state
* @user: ptr to use state
*
* Cleans up shared state and notifiers, callee is responsible for
* freeing the @VhostUserState memory itself.
*/
void vhost_user_cleanup(VhostUserState *user);
/**
* vhost_user_async_close() - cleanup vhost-user post connection drop
* @d: DeviceState for the associated device (passed to callback)
* @chardev: the CharBackend associated with the connection
* @vhost: the common vhost device
* @cb: the user callback function to complete the clean-up
*
* This function is used to handle the shutdown of a vhost-user
* connection to a backend. We handle this centrally to make sure we
* do all the steps and handle potential races due to VM shutdowns.
* Once the connection is disabled we call a backhalf to ensure
*/
typedef void (*vu_async_close_fn)(DeviceState *cb);
void vhost_user_async_close(DeviceState *d,
CharBackend *chardev, struct vhost_dev *vhost,
vu_async_close_fn cb,
IOEventHandler *event_cb);
#endif