65 lines
1.7 KiB
C
65 lines
1.7 KiB
C
/*
|
|
* QEMU System Emulator block write threshold notification
|
|
*
|
|
* Copyright Red Hat, Inc. 2014
|
|
*
|
|
* Authors:
|
|
* Francesco Romani <fromani@redhat.com>
|
|
*
|
|
* This work is licensed under the terms of the GNU LGPL, version 2 or later.
|
|
* See the COPYING.LIB file in the top-level directory.
|
|
*/
|
|
#ifndef BLOCK_WRITE_THRESHOLD_H
|
|
#define BLOCK_WRITE_THRESHOLD_H
|
|
|
|
#include <stdint.h>
|
|
|
|
#include "qemu/typedefs.h"
|
|
#include "qemu-common.h"
|
|
|
|
/*
|
|
* bdrv_write_threshold_set:
|
|
*
|
|
* Set the write threshold for block devices, in bytes.
|
|
* Notify when a write exceeds the threshold, meaning the device
|
|
* is becoming full, so it can be transparently resized.
|
|
* To be used with thin-provisioned block devices.
|
|
*
|
|
* Use threshold_bytes == 0 to disable.
|
|
*/
|
|
void bdrv_write_threshold_set(BlockDriverState *bs, uint64_t threshold_bytes);
|
|
|
|
/*
|
|
* bdrv_write_threshold_get
|
|
*
|
|
* Get the configured write threshold, in bytes.
|
|
* Zero means no threshold configured.
|
|
*/
|
|
uint64_t bdrv_write_threshold_get(const BlockDriverState *bs);
|
|
|
|
/*
|
|
* bdrv_write_threshold_is_set
|
|
*
|
|
* Tell if a write threshold is set for a given BDS.
|
|
*/
|
|
bool bdrv_write_threshold_is_set(const BlockDriverState *bs);
|
|
|
|
/*
|
|
* bdrv_write_threshold_exceeded
|
|
*
|
|
* Return the extent of a write request that exceeded the threshold,
|
|
* or zero if the request is below the threshold.
|
|
* Return zero also if the threshold was not set.
|
|
*
|
|
* NOTE: here we assume the following holds for each request this code
|
|
* deals with:
|
|
*
|
|
* assert((req->offset + req->bytes) <= UINT64_MAX)
|
|
*
|
|
* Please not there is *not* an actual C assert().
|
|
*/
|
|
uint64_t bdrv_write_threshold_exceeded(const BlockDriverState *bs,
|
|
const BdrvTrackedRequest *req);
|
|
|
|
#endif
|