scsi/008: Test SCSI disk data lifetime support

SCSI disk data lifetime support is available since kernel v6.9-rc1.
See also https://lore.kernel.org/linux-scsi/3b789eacddd6265921be9da6e15257908f29b186.camel@HansenPartnership.com/.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>

common/scsi_debug

@@ -25,6 +25,20 @@ _scsi_debug_key_path() {
 	echo "$path"
 }
 
+_have_scsi_debug_group_number_stats() {
+	local ret=0
+
+	modprobe -qr scsi_debug >&/dev/null
+	if ! modprobe -q scsi_debug delay=0 >&/dev/null ||
+		! [[ -e ${SD_PSEUDO_PATH}/group_number_stats ]]
+	then
+		SKIP_REASONS+=("scsi_debug does not support group number statistics")
+		ret=1
+	fi
+	modprobe -qr scsi_debug >&/dev/null
+	return ${ret}
+}
+
 declare -a SCSI_DEBUG_HOSTS
 declare -a SCSI_DEBUG_TARGETS
 declare -a SCSI_DEBUG_DEVICES

tests/scsi/008

@@ -0,0 +1,82 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-3.0+
+# Copyright (C) 2024 Google LLC
+
+. tests/scsi/rc
+. common/null_blk
+. common/scsi_debug
+
+DESCRIPTION="test block data lifetime support"
+QUICK=1
+
+requires() {
+	_have_fio
+	_have_scsi_debug_group_number_stats
+}
+
+submit_io() {
+	local stats_attr=/sys/bus/pseudo/drivers/scsi_debug/group_number_stats
+	echo "$1 ($3)"
+	echo "$*" >>"${FULL}"
+	local direct_io=$2
+	echo 0 > "${stats_attr}" &&
+	local fio_args wh &&
+	for wh in none short medium long extreme; do
+		if [ "${direct_io}" = 0 ]; then
+			sync
+			echo 1 > /proc/sys/vm/drop_caches
+		fi
+		fio_args=(
+			--bs=4K
+			--buffer_pattern='"'"$wh"'"'
+			--direct="${direct_io}"
+			--disable_clat=1
+			--disable_slat=1
+			--end_fsync=$((1 - direct_io))
+			--filename="${dev}"
+			--group_reporting=1
+			--gtod_reduce=1
+			--ioengine="$3"
+			--ioscheduler=none
+			--name=whint_"$wh"
+			--norandommap
+			--rw=randwrite
+			--size=4M
+			--thread=1
+			--write_hint="$wh"
+		)
+		echo "fio ${fio_args[*]}" >>"${FULL}" 2>&1
+		fio "${fio_args[@]}" >>"${FULL}" 2>&1 || return $?
+	done &&
+	grep -v ' 0$' "${stats_attr}" >> "${FULL}"
+	while read -r group count; do
+		if [ "$count" -gt 0 ]; then echo "$group"; fi
+	done < "${stats_attr}"
+}
+
+test() {
+	echo "Running ${TEST_NAME}"
+
+	local scsi_debug_params=(
+		delay=0
+		dev_size_mb=1024
+		sector_size=4096
+	)
+	_configure_scsi_debug "${scsi_debug_params[@]}" &&
+	local dev="/dev/${SCSI_DEBUG_DEVICES[0]}" fail &&
+	ls -ldi "${dev}" >>"${FULL}" &&
+	submit_io "Direct I/O" 1 pvsync &&
+	submit_io "Direct I/O" 1 libaio &&
+	submit_io "Direct I/O" 1 io_uring &&
+	submit_io "Buffered I/O" 0 pvsync ||
+	fail=true
+
+	_exit_scsi_debug
+
+	if [ -z "$fail" ]; then
+		echo "Test complete"
+	else
+		echo "Test failed"
+		return 1
+	fi
+}

tests/scsi/008.out

@@ -0,0 +1,26 @@
+Running scsi/008
+Direct I/O (pvsync)
+1
+2
+3
+4
+5
+Direct I/O (libaio)
+1
+2
+3
+4
+5
+Direct I/O (io_uring)
+1
+2
+3
+4
+5
+Buffered I/O (pvsync)
+1
+2
+3
+4
+5
+Test complete