LXR qemu/include/block/write-threshold.h

   1/*
   2 * QEMU System Emulator block write threshold notification
   3 *
   4 * Copyright Red Hat, Inc. 2014
   5 *
   6 * Authors:
   7 *  Francesco Romani <fromani@redhat.com>
   8 *
   9 * This work is licensed under the terms of the GNU LGPL, version 2 or later.
  10 * See the COPYING.LIB file in the top-level directory.
  11 */
  12
  13#ifndef BLOCK_WRITE_THRESHOLD_H
  14#define BLOCK_WRITE_THRESHOLD_H
  15
  16#include "qemu/typedefs.h"
  17
  18/*
  19 * bdrv_write_threshold_set:
  20 *
  21 * Set the write threshold for block devices, in bytes.
  22 * Notify when a write exceeds the threshold, meaning the device
  23 * is becoming full, so it can be transparently resized.
  24 * To be used with thin-provisioned block devices.
  25 *
  26 * Use threshold_bytes == 0 to disable.
  27 */
  28void bdrv_write_threshold_set(BlockDriverState *bs, uint64_t threshold_bytes);
  29
  30/*
  31 * bdrv_write_threshold_get
  32 *
  33 * Get the configured write threshold, in bytes.
  34 * Zero means no threshold configured.
  35 */
  36uint64_t bdrv_write_threshold_get(const BlockDriverState *bs);
  37
  38/*
  39 * bdrv_write_threshold_check_write
  40 *
  41 * Check whether the specified request exceeds the write threshold.
  42 * If so, send a corresponding event and disable write threshold checking.
  43 */
  44void bdrv_write_threshold_check_write(BlockDriverState *bs, int64_t offset,
  45                                      int64_t bytes);
  46
  47#endif
  48