@@ -23,22 +23,25 @@ if [ $? -eq 0 ]; then
_notrun "Cannot run tests with DAX on dmerror devices"
fi
-_dmerror_init()
+_dmerror_setup()
{
local dm_backing_dev=$SCRATCH_DEV
- $DMSETUP_PROG remove error-test > /dev/null 2>&1
-
local blk_dev_size=`blockdev --getsz $dm_backing_dev`
DMERROR_DEV='/dev/mapper/error-test'
DMLINEAR_TABLE="0 $blk_dev_size linear $dm_backing_dev 0"
+ DMERROR_TABLE="0 $blk_dev_size error $dm_backing_dev 0"
+}
+
+_dmerror_init()
+{
+ _dmerror_setup
+ $DMSETUP_PROG remove error-test > /dev/null 2>&1
$DMSETUP_PROG create error-test --table "$DMLINEAR_TABLE" || \
_fatal "failed to create dm linear device"
-
- DMERROR_TABLE="0 $blk_dev_size error $dm_backing_dev 0"
}
_dmerror_mount()
@@ -12,7 +12,7 @@ TARGETS = dirstress fill fill2 getpagesize holes lstat64 \
godown resvtest writemod makeextents itrash rename \
multi_open_unlink dmiperf unwritten_sync genhashnames t_holes \
t_mmap_writev t_truncate_cmtime dirhash_collide t_rename_overwrite \
- holetest t_truncate_self t_mmap_dio af_unix
+ holetest t_truncate_self t_mmap_dio af_unix fsync-err
LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \
preallo_rw_pattern_writer ftrunc trunc fs_perms testx looptest \
new file mode 100644
@@ -0,0 +1,102 @@
+/*
+ * fsync-err.c: test whether writeback errors are reported to all open fds
+ * Copyright (c) 2017: Jeff Layton <jlayton@redhat.com>
+ *
+ * Open a file several times, write to it and then fsync. Flip dm_error over
+ * to make the backing device stop working. Overwrite the same section and
+ * call fsync on all fds and verify that we get errors on all of them. Then,
+ * fsync one more time on all of them and verify that they return 0.
+ */
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#define NUM_FDS 10
+
+static void usage() {
+ fprintf(stderr, "Usage: fsync-err <filename>\n");
+}
+
+int main(int argc, char **argv)
+{
+ int fd[NUM_FDS], ret, i;
+ char *fname, *buf;
+
+ if (argc < 1) {
+ usage();
+ return 1;
+ }
+
+ /* First argument is filename */
+ fname = argv[1];
+
+ for (i = 0; i < NUM_FDS; ++i) {
+ fd[i] = open(fname, O_WRONLY | O_CREAT | O_TRUNC, 0644);
+ if (fd[i] < 0) {
+ printf("open of fd[%d] failed: %m\n", i);
+ return 1;
+ }
+ }
+
+ buf = "foobar";
+ for (i = 0; i < NUM_FDS; ++i) {
+ ret = write(fd[i], buf, strlen(buf) + 1);
+ if (ret < 0) {
+ printf("First write on fd[%d] failed: %m\n", i);
+ return 1;
+ }
+ }
+
+ for (i = 0; i < NUM_FDS; ++i) {
+ ret = fsync(fd[i]);
+ if (ret < 0) {
+ printf("First fsync on fd[%d] failed: %m\n", i);
+ return 1;
+ }
+ }
+
+ /* flip the device to non-working mode */
+ ret = system("./tools/dmerror load_error_table");
+ if (ret) {
+ if (WIFEXITED(ret))
+ printf("system: program exited: %d\n",
+ WEXITSTATUS(ret));
+ else
+ printf("system: 0x%x\n", (int)ret);
+
+ return 1;
+ }
+
+ for (i = 0; i < NUM_FDS; ++i) {
+ ret = write(fd[i], buf, strlen(buf) + 1);
+ if (ret < 0) {
+ printf("Second write on fd[%d] failed: %m\n", i);
+ return 1;
+ }
+ }
+
+ for (i = 0; i < NUM_FDS; ++i) {
+ ret = fsync(fd[i]);
+ /* Now, we EXPECT the error! */
+ if (ret >= 0) {
+ printf("Success on second fsync on fd[%d]!\n", i);
+ return 1;
+ }
+ }
+
+ for (i = 0; i < NUM_FDS; ++i) {
+ ret = fsync(fd[i]);
+ if (ret < 0) {
+ /* Now the error should be clear */
+ printf("Third fsync on fd[%d] failed: %m\n", i);
+ return 1;
+ }
+ }
+ printf("Test passed!\n");
+ return 0;
+}
new file mode 100755
@@ -0,0 +1,74 @@
+#! /bin/bash
+# FS QA Test No. 999
+#
+# Open a file several times, write to it, fsync on all fds and make sure that
+# they all return 0. Change the device to start throwing errors. Write again
+# on all fds and fsync on all fds. Ensure that we get errors on all of them.
+# Then fsync on all one last time and verify that all return 0.
+#
+#-----------------------------------------------------------------------
+# Copyright (c) 2017, Jeff Layton <jlayton@redhat.com>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it would be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write the Free Software Foundation,
+# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+#-----------------------------------------------------------------------
+
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1 # failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+ cd /
+ rm -rf $tmp.* $testdir
+ _dmerror_cleanup
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+. ./common/dmerror
+
+# real QA test starts here
+_supported_os Linux
+_require_scratch
+_require_dm_target error
+
+rm -f $seqres.full
+
+echo "Format and mount"
+$XFS_IO_PROG -d -c "pwrite -S 0x7c -b 1048576 0 $((64 * 1048576))" $SCRATCH_DEV >> $seqres.full
+_scratch_mkfs_sized $((64 * 1048576)) > $seqres.full 2>&1
+_dmerror_init
+_dmerror_mount >> $seqres.full 2>&1
+_dmerror_unmount
+_dmerror_mount
+
+_require_fs_space $SCRATCH_MNT 8192
+
+testfile=$SCRATCH_MNT/fsync-err-test
+
+$here/src/fsync-err $testfile
+
+# success, all done
+_dmerror_load_working_table
+_dmerror_unmount
+_dmerror_cleanup
+_repair_scratch_fs >> $seqres.full
+status=0
+exit
new file mode 100644
@@ -0,0 +1,3 @@
+QA output created by 999
+Format and mount
+Test passed!
@@ -428,3 +428,4 @@
423 auto quick
424 auto quick
425 auto quick attr
+999 auto quick
new file mode 100755
@@ -0,0 +1,47 @@
+#!/bin/bash
+#-----------------------------------------------------------------------
+# Copyright (c) 2017, Jeff Layton <jlayton@redhat.com>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it would be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write the Free Software Foundation,
+# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+#-----------------------------------------------------------------------
+
+. ./common/rc
+. ./common/dmerror
+
+_dmerror_setup
+
+case $1 in
+cleanup)
+ _dmerror_cleanup
+ ;;
+init)
+ _dmerror_init
+ ;;
+load_error_table)
+ _dmerror_load_error_table
+ ;;
+load_working_table)
+ _dmerror_load_working_table
+ ;;
+mount)
+ _dmerror_mount
+ ;;
+*)
+ echo "Usage: $0 {load_error_table}"
+ exit 1
+ ;;
+esac
+
+status=0
+exit
This is just an RFC set for now. I've numbered it 999 for the moment so as not to collide with tests being added. I'm working on a set of kernel patches to change how writeback errors are handled and reported in the kernel. Instead of reporting a writeback error to only the first fsync caller on the file, I aim to make the kernel report them once on every file description: https://lkml.org/lkml/2017/4/24/438 This patch adds a test for the new behavior. Basically, open many fds to the same file, turn on dm_error, write to each of the fds, and then fsync them all to ensure that they all get an error back. With the patch series above, ext4 now passes. xfs and btrfs end up in r/o mode after the test. xfs returns -EIO at that point though, and btrfs returns -EROFS. What behavior we actually want there, I'm not certain. We might be able to mitigate that by putting the journals on a separate device? Signed-off-by: Jeff Layton <jlayton@redhat.com> --- common/dmerror | 13 ++++--- src/Makefile | 2 +- src/fsync-err.c | 102 ++++++++++++++++++++++++++++++++++++++++++++++++++ tests/generic/999 | 74 ++++++++++++++++++++++++++++++++++++ tests/generic/999.out | 3 ++ tests/generic/group | 1 + tools/dmerror | 47 +++++++++++++++++++++++ 7 files changed, 236 insertions(+), 6 deletions(-) create mode 100644 src/fsync-err.c create mode 100755 tests/generic/999 create mode 100644 tests/generic/999.out create mode 100755 tools/dmerror