LXR qemu/block/copy-before-write.h

   1/*
   2 * copy-before-write filter driver
   3 *
   4 * The driver performs Copy-Before-Write (CBW) operation: it is injected above
   5 * some node, and before each write it copies _old_ data to the target node.
   6 *
   7 * Copyright (c) 2018-2021 Virtuozzo International GmbH.
   8 *
   9 * Author:
  10 *  Sementsov-Ogievskiy Vladimir <vsementsov@virtuozzo.com>
  11 *
  12 * This program is free software; you can redistribute it and/or modify
  13 * it under the terms of the GNU General Public License as published by
  14 * the Free Software Foundation; either version 2 of the License, or
  15 * (at your option) any later version.
  16 *
  17 * This program is distributed in the hope that it will be useful,
  18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 * GNU General Public License for more details.
  21 *
  22 * You should have received a copy of the GNU General Public License
  23 * along with this program. If not, see <http://www.gnu.org/licenses/>.
  24 */
  25
  26#ifndef COPY_BEFORE_WRITE_H
  27#define COPY_BEFORE_WRITE_H
  28
  29#include "block/block_int.h"
  30#include "block/block-copy.h"
  31
  32/*
  33 * Global state (GS) API. These functions run under the BQL.
  34 *
  35 * See include/block/block-global-state.h for more information about
  36 * the GS API.
  37 */
  38
  39BlockDriverState *bdrv_cbw_append(BlockDriverState *source,
  40                                  BlockDriverState *target,
  41                                  const char *filter_node_name,
  42                                  BlockCopyState **bcs,
  43                                  Error **errp);
  44void bdrv_cbw_drop(BlockDriverState *bs);
  45
  46#endif /* COPY_BEFORE_WRITE_H */
  47