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/*
* QEMU Block backends
*
* Copyright (C) 2014-2016 Red Hat, Inc.
*
* Authors:
* Markus Armbruster <armbru@redhat.com>,
*
* This work is licensed under the terms of the GNU LGPL, version 2.1
* or later. See the COPYING.LIB file in the top-level directory.
*/
#ifndef BLOCK_BACKEND_COMMON_H
#define BLOCK_BACKEND_COMMON_H
#include "qemu/iov.h"
#include "block/throttle-groups.h"
/*
* TODO Have to include block/block.h for a bunch of block layer
* types. Unfortunately, this pulls in the whole BlockDriverState
* API, which we don't want used by many BlockBackend users. Some of
* the types belong here, and the rest should be split into a common
* header and one for the BlockDriverState API.
*/
#include "block/block.h"
/* Callbacks for block device models */
typedef struct BlockDevOps {
/*
* Global state (GS) API. These functions run under the BQL.
*
* See include/block/block-global-state.h for more information about
* the GS API.
*/
/*
* Runs when virtual media changed (monitor commands eject, change)
* Argument load is true on load and false on eject.
* Beware: doesn't run when a host device's physical media
* changes. Sure would be useful if it did.
* Device models with removable media must implement this callback.
*/
void (*change_media_cb)(void *opaque, bool load, Error **errp);
/*
* Runs when an eject request is issued from the monitor, the tray
* is closed, and the medium is locked.
* Device models that do not implement is_medium_locked will not need
* this callback. Device models that can lock the medium or tray might
* want to implement the callback and unlock the tray when "force" is
* true, even if they do not support eject requests.
*/
void (*eject_request_cb)(void *opaque, bool force);
/*
* Is the virtual medium locked into the device?
* Device models implement this only when device has such a lock.
*/
bool (*is_medium_locked)(void *opaque);
/*
* Runs when the backend receives a drain request.
*/
void (*drained_begin)(void *opaque);
/*
* Runs when the backend's last drain request ends.
*/
void (*drained_end)(void *opaque);
/*
* Is the device still busy?
*/
bool (*drained_poll)(void *opaque);
/*
* I/O API functions. These functions are thread-safe.
*
* See include/block/block-io.h for more information about
* the I/O API.
*/
/*
* Is the virtual tray open?
* Device models implement this only when the device has a tray.
*/
bool (*is_tray_open)(void *opaque);
/*
* Runs when the size changed (e.g. monitor command block_resize)
*/
void (*resize_cb)(void *opaque);
} BlockDevOps;
/*
* This struct is embedded in (the private) BlockBackend struct and contains
* fields that must be public. This is in particular for QLIST_ENTRY() and
* friends so that BlockBackends can be kept in lists outside block-backend.c
*/
typedef struct BlockBackendPublic {
ThrottleGroupMember throttle_group_member;
} BlockBackendPublic;
#endif /* BLOCK_BACKEND_COMMON_H */
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