The patch titled
Subject: selftests/filesystems: add a vfat RENAME_EXCHANGE test
has been added to the -mm mm-nonmm-unstable branch. Its filename is
selftests-filesystems-add-a-vfat-rename_exchange-test.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-filesystems-add-a-vfat-rename_exchange-test.patch
This patch will later appear in the mm-nonmm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Javier Martinez Canillas <javierm@xxxxxxxxxx>
Subject: selftests/filesystems: add a vfat RENAME_EXCHANGE test
Date: Fri, 10 Jun 2022 09:57:21 +0200
Add a test for the renameat2 RENAME_EXCHANGE support in vfat, but split it
in a tool that just does the rename exchange and a script that is run by
the kselftests framework on `make TARGETS="filesystems/fat" kselftest`.
That way the script can be easily extended to test other file operations.
The script creates a 1 MiB disk image, that is then formated with a vfat
filesystem and mounted using a loop device. That way all file operations
are done on an ephemeral filesystem.
Link: https://lkml.kernel.org/r/20220610075721.1182745-5-javierm@xxxxxxxxxx
Signed-off-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>
Acked-by: Muhammad Usama Anjum <usama.anjum@xxxxxxxxxxxxx>
Acked-by: OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx>
Cc: Alexander Larsson <alexl@xxxxxxxxxx>
Cc: Christian Kellner <ckellner@xxxxxxxxxx>
Cc: Chung-Chiang Cheng <cccheng@xxxxxxxxxxxx>
Cc: Colin Walters <walters@xxxxxxxxxx>
Cc: Lennart Poettering <lennart@xxxxxxxxxxxxxx>
Cc: Peter Jones <pjones@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
MAINTAINERS | 1
tools/testing/selftests/Makefile | 1
tools/testing/selftests/filesystems/fat/.gitignore | 2
tools/testing/selftests/filesystems/fat/Makefile | 7
tools/testing/selftests/filesystems/fat/config | 2
tools/testing/selftests/filesystems/fat/rename_exchange.c | 37 ++++
tools/testing/selftests/filesystems/fat/run_fat_tests.sh | 82 ++++++++++
7 files changed, 132 insertions(+)
--- a/MAINTAINERS~selftests-filesystems-add-a-vfat-rename_exchange-test
+++ a/MAINTAINERS
@@ -20916,6 +20916,7 @@ M: OGAWA Hirofumi <hirofumi@mail.parknet
S: Maintained
F: Documentation/filesystems/vfat.rst
F: fs/fat/
+F: tools/testing/selftests/filesystems/fat/
VFIO DRIVER
M: Alex Williamson <alex.williamson@xxxxxxxxxx>
--- /dev/null
+++ a/tools/testing/selftests/filesystems/fat/config
@@ -0,0 +1,2 @@
+CONFIG_BLK_DEV_LOOP=y
+CONFIG_VFAT_FS=y
--- /dev/null
+++ a/tools/testing/selftests/filesystems/fat/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+rename_exchange
--- /dev/null
+++ a/tools/testing/selftests/filesystems/fat/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+
+TEST_PROGS := run_fat_tests.sh
+TEST_GEN_PROGS_EXTENDED := rename_exchange
+CFLAGS += -O2 -g -Wall $(KHDR_INCLUDES)
+
+include ../../lib.mk
--- /dev/null
+++ a/tools/testing/selftests/filesystems/fat/rename_exchange.c
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Program that atomically exchanges two paths using
+ * the renameat2() system call RENAME_EXCHANGE flag.
+ *
+ * Copyright 2022 Red Hat Inc.
+ * Author: Javier Martinez Canillas <javierm@xxxxxxxxxx>
+ */
+
+#define _GNU_SOURCE
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+void print_usage(const char *program)
+{
+ printf("Usage: %s [oldpath] [newpath]\n", program);
+ printf("Atomically exchange oldpath and newpath\n");
+}
+
+int main(int argc, char *argv[])
+{
+ int ret;
+
+ if (argc != 3) {
+ print_usage(argv[0]);
+ exit(EXIT_FAILURE);
+ }
+
+ ret = renameat2(AT_FDCWD, argv[1], AT_FDCWD, argv[2], RENAME_EXCHANGE);
+ if (ret) {
+ perror("rename exchange failed");
+ exit(EXIT_FAILURE);
+ }
+
+ exit(EXIT_SUCCESS);
+}
--- /dev/null
+++ a/tools/testing/selftests/filesystems/fat/run_fat_tests.sh
@@ -0,0 +1,82 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Run filesystem operations tests on an 1 MiB disk image that is formatted with
+# a vfat filesystem and mounted in a temporary directory using a loop device.
+#
+# Copyright 2022 Red Hat Inc.
+# Author: Javier Martinez Canillas <javierm@xxxxxxxxxx>
+
+set -e
+set -u
+set -o pipefail
+
+BASE_DIR="$(dirname $0)"
+TMP_DIR="$(mktemp -d /tmp/fat_tests_tmp.XXXX)"
+IMG_PATH="${TMP_DIR}/fat.img"
+MNT_PATH="${TMP_DIR}/mnt"
+
+cleanup()
+{
+ mountpoint -q "${MNT_PATH}" && unmount_image
+ rm -rf "${TMP_DIR}"
+}
+trap cleanup SIGINT SIGTERM EXIT
+
+create_loopback()
+{
+ touch "${IMG_PATH}"
+ chattr +C "${IMG_PATH}" >/dev/null 2>&1 || true
+
+ truncate -s 1M "${IMG_PATH}"
+ mkfs.vfat "${IMG_PATH}" >/dev/null 2>&1
+}
+
+mount_image()
+{
+ mkdir -p "${MNT_PATH}"
+ sudo mount -o loop "${IMG_PATH}" "${MNT_PATH}"
+}
+
+rename_exchange_test()
+{
+ local rename_exchange="${BASE_DIR}/rename_exchange"
+ local old_path="${MNT_PATH}/old_file"
+ local new_path="${MNT_PATH}/new_file"
+
+ echo old | sudo tee "${old_path}" >/dev/null 2>&1
+ echo new | sudo tee "${new_path}" >/dev/null 2>&1
+ sudo "${rename_exchange}" "${old_path}" "${new_path}" >/dev/null 2>&1
+ sudo sync -f "${MNT_PATH}"
+ grep new "${old_path}" >/dev/null 2>&1
+ grep old "${new_path}" >/dev/null 2>&1
+}
+
+rename_exchange_subdir_test()
+{
+ local rename_exchange="${BASE_DIR}/rename_exchange"
+ local dir_path="${MNT_PATH}/subdir"
+ local old_path="${MNT_PATH}/old_file"
+ local new_path="${dir_path}/new_file"
+
+ sudo mkdir -p "${dir_path}"
+ echo old | sudo tee "${old_path}" >/dev/null 2>&1
+ echo new | sudo tee "${new_path}" >/dev/null 2>&1
+ sudo "${rename_exchange}" "${old_path}" "${new_path}" >/dev/null 2>&1
+ sudo sync -f "${MNT_PATH}"
+ grep new "${old_path}" >/dev/null 2>&1
+ grep old "${new_path}" >/dev/null 2>&1
+}
+
+unmount_image()
+{
+ sudo umount "${MNT_PATH}" &> /dev/null
+}
+
+create_loopback
+mount_image
+rename_exchange_test
+rename_exchange_subdir_test
+unmount_image
+
+exit 0
--- a/tools/testing/selftests/Makefile~selftests-filesystems-add-a-vfat-rename_exchange-test
+++ a/tools/testing/selftests/Makefile
@@ -17,6 +17,7 @@ TARGETS += exec
TARGETS += filesystems
TARGETS += filesystems/binderfs
TARGETS += filesystems/epoll
+TARGETS += filesystems/fat
TARGETS += firmware
TARGETS += fpu
TARGETS += ftrace
_
Patches currently in -mm which might be from javierm@xxxxxxxxxx are
fat-add-a-vfat_rename2-and-make-existing-rename-callback-a-helper.patch
fat-add-renameat2-rename_exchange-flag-support.patch
selftests-filesystems-add-a-vfat-rename_exchange-test.patch
