common/dmhugedisk

##/bin/bash
# SPDX-License-Identifier: GPL-2.0+
# Copyright (c) 2016 Oracle.  All Rights Reserved.
#
# Routines for creating huge (fake) disks

export DMHUGE_TEST="huge-test.$seq"
export DMHUGE_TEST_ZERO="huge-test-zero.$seq"

_require_dmhugedisk()
{
	_require_dm_target zero
	_require_dm_target snapshot
}

_dmhugedisk_init()
{
	test -z "$1" && _fatal "must specify sector count to _dmhugedisk_init"
	local dm_backing_dev=$SCRATCH_DEV
	local chunk_size="$2"

	if [ -z "$chunk_size" ]; then
		chunk_size=512
	fi

	_dmsetup_remove $DMHUGE_TEST
	_dmsetup_remove $DMHUGE_TEST_ZERO

	local blk_dev_size=$1

	DMHUGEDISK_ZERO="/dev/mapper/$DMHUGE_TEST_ZERO"
	DMHUGEDISK_DEV="/dev/mapper/$DMHUGE_TEST"

	DMHUGEDISK_ZERO_TABLE="0 $blk_dev_size zero"
	DMHUGEDISK_DEV_TABLE="0 $blk_dev_size snapshot $DMHUGEDISK_ZERO $SCRATCH_DEV N $chunk_size"

	_dmsetup_create $DMHUGE_TEST_ZERO --table "$DMHUGEDISK_ZERO_TABLE" || \
		_fatal "failed to create dm huge zero device"
	_dmsetup_create $DMHUGE_TEST --table "$DMHUGEDISK_DEV_TABLE" || \
		_fatal "failed to create dm huge device"
}

_dmhugedisk_cleanup()
{
	_unmount $SCRATCH_MNT > /dev/null 2>&1
	_dmsetup_remove $DMHUGE_TEST
	_dmsetup_remove $DMHUGE_TEST_ZERO
}