qemu/block/backup-top.h
Vladimir Sementsov-Ogievskiy 7df7868b96 block: introduce backup-top filter driver
Backup-top filter caches write operations and does copy-before-write
operations.

The driver will be used in backup instead of write-notifiers.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20191001131409.14202-5-vsementsov@virtuozzo.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-10 10:56:18 +02:00

41 lines
1.6 KiB
C

/*
* backup-top filter driver
*
* The driver performs Copy-Before-Write (CBW) operation: it is injected above
* some node, and before each write it copies _old_ data to the target node.
*
* Copyright (c) 2018-2019 Virtuozzo International GmbH.
*
* Author:
* Sementsov-Ogievskiy Vladimir <vsementsov@virtuozzo.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef BACKUP_TOP_H
#define BACKUP_TOP_H
#include "block/block_int.h"
#include "block/block-copy.h"
BlockDriverState *bdrv_backup_top_append(BlockDriverState *source,
BlockDriverState *target,
const char *filter_node_name,
uint64_t cluster_size,
BdrvRequestFlags write_flags,
BlockCopyState **bcs,
Error **errp);
void bdrv_backup_top_drop(BlockDriverState *bs);
#endif /* BACKUP_TOP_H */