vfio: selftests: Split run.sh into separate scripts

Split run.sh into separate scripts (setup.sh, run.sh, cleanup.sh) to
enable multi-device testing, and prepare for VFIO selftests
automatically detecting which devices to use for testing by storing
device metadata on the filesystem.

 - setup.sh takes one or more BDFs as arguments and sets up each device.
   Metadata about each device is stored on the filesystem in the
   directory:

	   ${TMPDIR:-/tmp}/vfio-selftests-devices

   Within this directory is a directory for each BDF, and then files in
   those directories that cleanup.sh uses to cleanup the device.

 - run.sh runs a selftest by passing it the BDFs of all set up devices.

 - cleanup.sh takes zero or more BDFs as arguments and cleans up each
   device. If no BDFs are provided, it cleans up all devices.

This split enables multi-device testing by allowing multiple BDFs to be
set up and passed into tests:

For example:

  $ tools/testing/selftests/vfio/scripts/setup.sh <BDF1> <BDF2>
  $ tools/testing/selftests/vfio/scripts/setup.sh <BDF3>
  $ tools/testing/selftests/vfio/scripts/run.sh echo
  <BDF1> <BDF2> <BDF3>
  $ tools/testing/selftests/vfio/scripts/cleanup.sh

In the future, VFIO selftests can automatically detect set up devices by
inspecting ${TMPDIR:-/tmp}/vfio-selftests-devices. This will avoid the
need for the run.sh script.

Reviewed-by: Alex Mastro <amastro@fb.com>
Tested-by: Alex Mastro <amastro@fb.com>
Reviewed-by: Raghavendra Rao Ananta <rananta@google.com>
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20251126231733.3302983-3-dmatlack@google.com
Signed-off-by: Alex Williamson <alex@shazbot.org>

1 files changed, 48 insertions, 0 deletions

diff --git a/tools/testing/selftests/vfio/scripts/setup.sh b/tools/testing/selftests/vfio/scripts/setup.sh
new file mode 100755
index 000000000000..49a499e51cbe
--- /dev/null
+++ b/tools/testing/selftests/vfio/scripts/setup.sh
@@ -0,0 +1,48 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+set -e
+
+source $(dirname -- "${BASH_SOURCE[0]}")/lib.sh
+
+function main() {
+	local device_bdf
+	local device_dir
+	local numvfs
+	local driver
+
+	if [ $# = 0 ]; then
+		echo "usage: $0 segment:bus:device.function ..." >&2
+		exit 1
+	fi
+
+	for device_bdf in "$@"; do
+		test -d /sys/bus/pci/devices/${device_bdf}
+
+		device_dir=${DEVICES_DIR}/${device_bdf}
+		if [ -d "${device_dir}" ]; then
+			echo "${device_bdf} has already been set up, exiting."
+			exit 0
+		fi
+
+		mkdir -p ${device_dir}
+
+		numvfs=$(get_sriov_numvfs ${device_bdf})
+		if [ "${numvfs}" ]; then
+			set_sriov_numvfs ${device_bdf} 0
+			echo ${numvfs} > ${device_dir}/sriov_numvfs
+		fi
+
+		driver=$(get_driver ${device_bdf})
+		if [ "${driver}" ]; then
+			unbind ${device_bdf} ${driver}
+			echo ${driver} > ${device_dir}/driver
+		fi
+
+		set_driver_override ${device_bdf} vfio-pci
+		touch ${device_dir}/driver_override
+
+		bind ${device_bdf} vfio-pci
+		touch ${device_dir}/vfio-pci
+	done
+}
+
+main "$@"