The test helps to validate clamping and mount behaviors
according to supported file system timestamp ranges.
Note that the test can fail on 32-bit systems for a
few file systems. This will be corrected when vfs is
transitioned to use 64-bit timestamps.
Signed-off-by: Deepa Dinamani <deepa.kernel(a)gmail.com>
---
The branch of the kernel tree can be located at
https://github.com/deepa-hub/vfs refs/heads/vfs_timestamp_policy
The xfs_io patch to add utimes is at
https://www.spinics.net/lists/linux-xfs/msg02952.html
Changes since v2:
* Refactored notrun handling
* Updated comments
Changes since v1:
* Use xfs_io utimes command
* Updated error handling
* Reorganized code according to review comments
common/rc | 48 +++++++++++++
tests/generic/390 | 192 ++++++++++++++++++++++++++++++++++++++++++++++++++
tests/generic/390.out | 2 +
tests/generic/group | 1 +
4 files changed, 243 insertions(+)
create mode 100755 tests/generic/390
create mode 100644 tests/generic/390.out
diff --git a/common/rc b/common/rc
index e3b54ec..17f025e 100644
--- a/common/rc
+++ b/common/rc
@@ -1960,6 +1960,51 @@ _run_aiodio()
return $status
}
+# this test requires y2038 sysfs switch and filesystem
+# timestamp ranges support.
+_require_y2038()
+{
+ local device=${1:-$TEST_DEV}
+ local sysfsdir=/proc/sys/fs/fs-timestamp-check-on
+
+ if [ ! -e $sysfsdir ]; then
+ _notrun "no kernel support for y2038 sysfs switch"
+ fi
+
+ local tsmin tsmax
+ read tsmin tsmax <<<$(_filesystem_timestamp_range $device)
+ if [ $tsmin -eq -1 -a $tsmax -eq -1 ]; then
+ _notrun "filesystem $FSTYP timestamp bounds are unknown"
+ fi
+}
+
+_filesystem_timestamp_range()
+{
+ device=${1:-$TEST_DEV}
+ case $FSTYP in
+ ext4)
+ if [ $(dumpe2fs -h $device 2>/dev/null | grep "Inode size:" | cut -d: -f2) -gt 128 ]; then
+ echo "-2147483648 15032385535"
+ else
+ echo "-2147483648 2147483647"
+ fi
+ ;;
+
+ xfs)
+ echo "-2147483648 2147483647"
+ ;;
+ jfs)
+ echo "0 4294967295"
+ ;;
+ f2fs)
+ echo "-2147483648 2147483647"
+ ;;
+ *)
+ echo "-1 -1"
+ ;;
+ esac
+}
+
# indicate whether YP/NIS is active or not
#
_yp_active()
@@ -2070,6 +2115,9 @@ _require_xfs_io_command()
echo $testio | egrep -q "Inappropriate ioctl" && \
_notrun "xfs_io $command support is missing"
;;
+ "utimes" )
+ testio=`$XFS_IO_PROG -f -c "utimes" 0 0 0 0 $testfile 2>&1`
+ ;;
*)
testio=`$XFS_IO_PROG -c "$command help" 2>&1`
esac
diff --git a/tests/generic/390 b/tests/generic/390
new file mode 100755
index 0000000..f68b931
--- /dev/null
+++ b/tests/generic/390
@@ -0,0 +1,192 @@
+#! /bin/bash
+# FS QA Test 390
+#
+# Tests to verify policy for filesystem timestamps for
+# supported ranges:
+# 1. Verify filesystem rw mount according to sysctl
+# timestamp_supported.
+# 2. Verify timestamp clamping for timestamps beyond max
+# timestamp supported.
+#
+# Exit status 1: either or both tests above fail.
+# Exit status 0: both the above tests pass.
+#
+#-----------------------------------------------------------------------
+# Copyright (c) 2016 Deepa Dinamani. All Rights Reserved.
+#
+# 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 "exit \$status" 0 1 2 3 15
+
+# Get standard environment, filters and checks.
+. ./common/rc
+. ./common/filter
+. ./common/attr
+
+# remove previous $seqres.full before test
+rm -f $seqres.full
+
+# Prerequisites for the test run.
+_supported_fs generic
+_supported_os Linux
+_require_scratch
+_require_xfs_io_command utimes
+
+# Compare file timestamps obtained from stat
+# with a given timestamp.
+check_stat()
+{
+ file=$1
+ timestamp=$2
+
+ stat_timestamp=`stat -c"%X;%Y" $file`
+
+ prev_timestamp="$timestamp;$timestamp"
+ if [ $prev_timestamp != $stat_timestamp ]; then
+ echo "$prev_timestamp != $stat_timestamp" | tee -a $seqres.full
+ fi
+}
+
+run_test_individual()
+{
+ file=$1
+ timestamp=$2
+ update_time=$3
+
+ #check if the time needs update
+ if [ $update_time -eq 1 ]; then
+ echo "Updating file: $file to timestamp `date -d @$timestamp`" >> $seqres.full
+ $XFS_IO_PROG -f -c "utimes $timestamp 0 $timestamp 0" $file
+ if [ $? -ne 0 ]; then
+ echo "Failed to update times on $file" | tee -a $seqres.full
+ fi
+ fi
+
+ tsclamp=$(($timestamp>$tsmax?$tsmax:$timestamp))
+ echo "Checking file: $file Updated timestamp is `date -d @$tsclamp`" >> $seqres.full
+ check_stat $file $tsclamp
+}
+
+run_test()
+{
+ update_time=$1
+
+ n=1
+
+ for TIME in "${TIMESTAMPS[@]}"
+ do
+ #Run the test
+ run_test_individual ${SCRATCH_MNT}/test_$n $TIME $update_time
+
+ #update iterator
+ ((n++))
+ done
+}
+
+_scratch_mkfs &>> $seqres.full 2>&1 || _fail "mkfs failed"
+_require_y2038 $SCRATCH_DEV
+
+read tsmin tsmax <<<$(_filesystem_timestamp_range $SCRATCH_DEV)
+echo min supported timestamp $tsmin $(date --date=@$tsmin) >> $seqres.full
+echo max supported timestamp $tsmax $(date --date=@$tsmax) >> $seqres.full
+
+# Test timestamps array
+
+declare -a TIMESTAMPS=(
+ $tsmin
+ 0
+ $tsmax
+ $((tsmax+1))
+ 4294967295
+ 8589934591
+ 34359738367
+)
+
+# Max timestamp is hardcoded to Mon Jan 18 19:14:07 PST 2038
+sys_tsmax=2147483647
+echo "max timestamp that needs to be supported by fs for rw mount is" \
+ "$((sys_tsmax+1)) $(date --date=@$((sys_tsmax+1)))" >> $seqres.full
+
+read ts_check <<<$(cat /proc/sys/fs/fs-timestamp-check-on)
+
+_scratch_mount
+result=$?
+
+if [ $ts_check -ne 0 ]; then
+ echo "sysctl filesystem timestamp check is on" >> $seqres.full
+ # check for mount failure if the minimum requirement for max timestamp
+ # supported is not met.
+ if [ $sys_tsmax -ge $tsmax ]; then
+ if [ $result -eq 0 ]; then
+ echo "mount test failed" | tee -a $seqres.full
+ exit
+ fi
+ else
+ if [ $result -ne 0 ]; then
+ echo "failed to mount $SCRATCH_DEV" | tee -a $seqres.full
+ exit
+ fi
+ fi
+else
+ # if sysctl switch is off then mount should succeed always.
+ echo "sysctl filesystem timestamp check is off" >> $seqres.full
+ if [ $result -ne 0 ]; then
+ echo "failed to mount $SCRATCH_DEV and timestamp check is off" >> $seqres.full
+ exit
+ fi
+fi
+
+# Begin test case 1
+echo "In memory timestamps update test start" >> $seqres.full
+
+# update time on the file
+update_time=1
+
+run_test $update_time
+
+echo "In memory timestamps update complete" >> $seqres.full
+
+echo "Unmounting and mounting scratch $SCRATCH_MNT" >> $seqres.full
+
+# unmount and remount $SCRATCH_DEV
+_scratch_cycle_mount
+
+# Begin test case 2
+
+n=1
+
+# Do not update time on the file this time, just read from disk
+update_time=0
+
+echo "On disk timestamps update test start" >> $seqres.full
+
+# Re-run test
+run_test $update_time
+
+echo "On disk timestamps update test complete" >> $seqres.full
+
+echo "y2038 inode timestamp tests completed successfully"
+
+# success, all done
+status=0
+exit
diff --git a/tests/generic/390.out b/tests/generic/390.out
new file mode 100644
index 0000000..82bd4eb
--- /dev/null
+++ b/tests/generic/390.out
@@ -0,0 +1,2 @@
+QA output created by 390
+y2038 inode timestamp tests completed successfully
diff --git a/tests/generic/group b/tests/generic/group
index 08007d7..d137d01 100644
--- a/tests/generic/group
+++ b/tests/generic/group
@@ -392,3 +392,4 @@
387 auto clone
388 auto log metadata
389 auto quick acl
+390 auto quick rw
--
2.7.4
Hi everyone,
This is a conversion of all subsystem-wide v4l2 code to avoid the
use of types based on time_t. The first five patches should all
be harmless and obvious, so they can get applied for 4.3 after
normal review.
The last two patches are marked RFC for now because their possible
impact on the user space ABI and to decide if this is the best
approach or whether we should instead introduce extra code in
the kernel to handle modified user space.
There are a few device drivers beyond this series that rely on
time_t/timeval/timespec internally, but they are all easy to fix
and can be taken care of later.
Arnd
Arnd Bergmann (7):
[media] dvb: use ktime_t for internal timeout
[media] dvb: remove unused systime() function
[media] dvb: don't use 'time_t' in event ioctl
[media] exynos4-is: use monotonic timestamps as advertized
[media] use v4l2_get_timestamp where possible
[RFC] [media]: v4l2: introduce v4l2_timeval
[RFC] [media] introduce v4l2_timespec type for timestamps
drivers/media/dvb-core/demux.h | 2 +-
drivers/media/dvb-core/dmxdev.c | 2 +-
drivers/media/dvb-core/dvb_demux.c | 17 ++++++-----------
drivers/media/dvb-core/dvb_demux.h | 4 ++--
drivers/media/dvb-core/dvb_net.c | 2 +-
drivers/media/dvb-frontends/dibx000_common.c | 10 ----------
drivers/media/dvb-frontends/dibx000_common.h | 2 --
drivers/media/pci/bt8xx/bttv-driver.c | 7 ++-----
drivers/media/pci/cx18/cx18-mailbox.c | 2 +-
drivers/media/pci/meye/meye.h | 2 +-
drivers/media/pci/zoran/zoran.h | 2 +-
drivers/media/platform/coda/coda.h | 2 +-
drivers/media/platform/exynos4-is/fimc-capture.c | 8 +-------
drivers/media/platform/exynos4-is/fimc-lite.c | 7 +------
drivers/media/platform/omap/omap_vout.c | 4 ++--
drivers/media/platform/omap3isp/ispstat.c | 5 ++---
drivers/media/platform/omap3isp/ispstat.h | 2 +-
drivers/media/platform/s3c-camif/camif-capture.c | 8 +-------
drivers/media/platform/vim2m.c | 2 +-
drivers/media/platform/vivid/vivid-ctrls.c | 2 +-
drivers/media/usb/cpia2/cpia2.h | 2 +-
drivers/media/usb/cpia2/cpia2_v4l.c | 2 +-
drivers/media/usb/gspca/gspca.c | 6 +++---
drivers/media/usb/usbvision/usbvision.h | 2 +-
drivers/media/v4l2-core/v4l2-common.c | 6 +++---
drivers/media/v4l2-core/v4l2-event.c | 20 +++++++++++++-------
drivers/staging/media/omap4iss/iss_video.c | 5 +----
include/media/v4l2-common.h | 2 +-
include/media/videobuf-core.h | 2 +-
include/trace/events/v4l2.h | 12 ++++++++++--
include/uapi/linux/dvb/video.h | 3 ++-
include/uapi/linux/omap3isp.h | 2 +-
include/uapi/linux/videodev2.h | 16 ++++++++++++++--
33 files changed, 79 insertions(+), 93 deletions(-)
--
2.1.0.rc2
Dear Customer,
We can not deliver your parcel arrived at January 23.
You can find more details in this e-mail attachment!
With thanks and appreciation,
Jaime Solomon,
USPS Station Manager.
I would like to discuss approaches to finish preparing the kernel to
be y2038 ready.
Arnd started the effort a few years ago and I'm working on a few parts
of the problem.
Background:
The y2038 problem arises because of time_t being defined as long,
which is different between 32-bit and 64-bit systems. This leaves
insufficient bits to represent time on a 32-bit system from the year
2038. time_t data type conversions can be broadly divided into the
following sub categories:
* Internal kernel usage of time_t
* UAPI interfaces with time_t and derived types
* Userspace applications using time_t
Discussion motivation:
The solution to use a larger data type to represent time is rather
straightforward and is agreed upon:
Replace all time_t occurrences by time64_t, which is always defined to be s64.
The tricky part is how to reach the goal of this transition without
breaking backward compatibility of interfaces internal and external to
the kernel. This can be done in more than one way. After long
discussions, we have managed to get some initial clean up patches
merged. These will help the VFS transition to using time64_t. It is
now a good time to look at the remaining problems in changing time_t.
Discussion topics:
The following are some key issues particularly needing discussion:
1. Time types we plan to retain within the kernel and in system APIs.
We posted multiple series, there have been a few changes since then.
https://lkml.org/lkml/2014/5/30/669https://lkml.org/lkml/2016/1/7/20
2. Syscall transition: Arnd had posted a version of this. There are a
few updates here as well. I intend to post an update soon.
https://sourceware.org/ml/libc-alpha/2015-05/msg00070.html
3. Policy for filesystems that do not support a y2038 safe on-disk
representation: I posted a series and the initial xfstest patch.
https://lwn.net/Articles/705358/https://www.spinics.net/lists/y2038/msg01945.html
4. VFS transition to using struct timespec64: I posted a few revisions
and our approach has changed for the cleanup patches. A discussion
would help pick an approach.
https://lwn.net/Articles/675381/
-Deepa
Dear Customer,
We can not deliver your parcel arrived at January 01.
Download postal receipt attached to e-mail!
With sincere appreciation,
Chester Hendrix,
USPS Mail Delivery Agent.
CURRENT_TIME is not y2038 safe.
CURRENT_TIME macro is also not appropriate for filesystems
as it doesn't use the right granularity for filesystem
timestamps.
Logical Volume Integrity format is described to have the
same timestamp format for "Recording Date and time" as
the other [a,c,m]timestamps.
The function udf_time_to_disk_format() does this conversion.
Hence the timestamp is passed directly to the function and
not truncated. This is as per Arnd's suggestion on the
thread.
This is also in preparation for the patch that transitions
vfs timestamps to use 64 bit time and hence make them
y2038 safe. As part of the effort current_time() will be
extended to do range checks.
Signed-off-by: Deepa Dinamani <deepa.kernel(a)gmail.com>
Reviewed-by: Jan Kara <jack(a)suse.cz>
Reviewed-by: Arnd Bergmann <arnd(a)arndb.de>
---
fs/udf/super.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/fs/udf/super.c b/fs/udf/super.c
index 4942549..967ad87 100644
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -1986,6 +1986,7 @@ static void udf_open_lvid(struct super_block *sb)
struct buffer_head *bh = sbi->s_lvid_bh;
struct logicalVolIntegrityDesc *lvid;
struct logicalVolIntegrityDescImpUse *lvidiu;
+ struct timespec ts;
if (!bh)
return;
@@ -1997,8 +1998,8 @@ static void udf_open_lvid(struct super_block *sb)
mutex_lock(&sbi->s_alloc_mutex);
lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
- udf_time_to_disk_stamp(&lvid->recordingDateAndTime,
- CURRENT_TIME);
+ ktime_get_real_ts(&ts);
+ udf_time_to_disk_stamp(&lvid->recordingDateAndTime, ts);
lvid->integrityType = cpu_to_le32(LVID_INTEGRITY_TYPE_OPEN);
lvid->descTag.descCRC = cpu_to_le16(
@@ -2019,6 +2020,7 @@ static void udf_close_lvid(struct super_block *sb)
struct buffer_head *bh = sbi->s_lvid_bh;
struct logicalVolIntegrityDesc *lvid;
struct logicalVolIntegrityDescImpUse *lvidiu;
+ struct timespec ts;
if (!bh)
return;
@@ -2030,7 +2032,8 @@ static void udf_close_lvid(struct super_block *sb)
mutex_lock(&sbi->s_alloc_mutex);
lvidiu->impIdent.identSuffix[0] = UDF_OS_CLASS_UNIX;
lvidiu->impIdent.identSuffix[1] = UDF_OS_ID_LINUX;
- udf_time_to_disk_stamp(&lvid->recordingDateAndTime, CURRENT_TIME);
+ ktime_get_real_ts(&ts);
+ udf_time_to_disk_stamp(&lvid->recordingDateAndTime, ts);
if (UDF_MAX_WRITE_VERSION > le16_to_cpu(lvidiu->maxUDFWriteRev))
lvidiu->maxUDFWriteRev = cpu_to_le16(UDF_MAX_WRITE_VERSION);
if (sbi->s_udfrev > le16_to_cpu(lvidiu->minUDFReadRev))
--
2.7.4
Add the utimes command to provide a way to utilize
the futimens C library call. This is the
interface to the utimensat system call, which updates
the mtime and atime of a file.
Signed-off-by: Deepa Dinamani <deepa.kernel(a)gmail.com>
Reviewed-by: Eric Sandeen <sandeen(a)redhat.com>
---
Changes since v2:
* fixed file permissions
Changes since v1:
* changed error return values
* removed redundant roff formatting directive
* removed unneeded argument count check
include/input.h | 1 +
io/Makefile | 2 +-
io/init.c | 1 +
io/io.h | 1 +
io/utimes.c | 81 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
libxcmd/input.c | 22 +++++++++++++++
man/man8/xfs_io.8 | 11 ++++++++
7 files changed, 118 insertions(+), 1 deletion(-)
create mode 100644 io/utimes.c
diff --git a/include/input.h b/include/input.h
index d02170f..221678e 100644
--- a/include/input.h
+++ b/include/input.h
@@ -48,6 +48,7 @@ extern uid_t uid_from_string(char *user);
extern gid_t gid_from_string(char *group);
extern prid_t prid_from_string(char *project);
extern bool isdigits_only(const char *str);
+extern int timespec_from_string(const char *sec, const char *nsec, struct timespec *ts);
#define HAVE_FTW_H 1 /* TODO: configure me */
diff --git a/io/Makefile b/io/Makefile
index 62bc03b..392e02a 100644
--- a/io/Makefile
+++ b/io/Makefile
@@ -11,7 +11,7 @@ HFILES = init.h io.h
CFILES = init.c \
attr.c bmap.c file.c freeze.c fsync.c getrusage.c imap.c link.c \
mmap.c open.c parent.c pread.c prealloc.c pwrite.c seek.c shutdown.c \
- sync.c truncate.c reflink.c
+ sync.c truncate.c reflink.c utimes.c
LLDLIBS = $(LIBXCMD) $(LIBHANDLE)
LTDEPENDENCIES = $(LIBXCMD) $(LIBHANDLE)
diff --git a/io/init.c b/io/init.c
index efe7390..6319aeb 100644
--- a/io/init.c
+++ b/io/init.c
@@ -85,6 +85,7 @@ init_commands(void)
sync_range_init();
truncate_init();
reflink_init();
+ utimes_init();
}
static int
diff --git a/io/io.h b/io/io.h
index 2bc7ac4..fddd7a3 100644
--- a/io/io.h
+++ b/io/io.h
@@ -113,6 +113,7 @@ extern void seek_init(void);
extern void shutdown_init(void);
extern void sync_init(void);
extern void truncate_init(void);
+extern void utimes_init(void);
#ifdef HAVE_FADVISE
extern void fadvise_init(void);
diff --git a/io/utimes.c b/io/utimes.c
new file mode 100644
index 0000000..faf9b8d
--- /dev/null
+++ b/io/utimes.c
@@ -0,0 +1,81 @@
+/*
+ * Copyright (c) 2016 Deepa Dinamani
+ * All Rights Reserved.
+ *
+ * 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
+ */
+
+#include "command.h"
+#include "input.h"
+#include "init.h"
+#include "io.h"
+
+static cmdinfo_t utimes_cmd;
+
+static void
+utimes_help(void)
+{
+ printf(_(
+"\n"
+" Update file atime and mtime of the current file with nansecond precision.\n"
+"\n"
+" Usage: utimes atime_sec atime_nsec mtime_sec mtime_nsec.\n"
+" *_sec: Seconds elapsed since 1970-01-01 00:00:00 UTC.\n"
+" *_nsec: Nanoseconds since the corresponding *_sec.\n"
+"\n"));
+}
+
+static int
+utimes_f(
+ int argc,
+ char **argv)
+{
+ struct timespec t[2];
+ int result;
+
+ /* Get the timestamps */
+ result = timespec_from_string(argv[1], argv[2], &t[0]);
+ if (result) {
+ fprintf(stderr, "Bad value for atime\n");
+ return 0;
+ }
+ result = timespec_from_string(argv[3], argv[4], &t[1]);
+ if (result) {
+ fprintf(stderr, "Bad value for mtime\n");
+ return 0;
+ }
+
+ /* Call futimens to update time. */
+ if (futimens(file->fd, t)) {
+ perror("futimens");
+ return 0;
+ }
+
+ return 0;
+}
+
+void
+utimes_init(void)
+{
+ utimes_cmd.name = "utimes";
+ utimes_cmd.cfunc = utimes_f;
+ utimes_cmd.argmin = 4;
+ utimes_cmd.argmax = 4;
+ utimes_cmd.flags = CMD_NOMAP_OK | CMD_FOREIGN_OK;
+ utimes_cmd.args = _("atime_sec atime_nsec mtime_sec mtime_nsec");
+ utimes_cmd.oneline = _("Update file times of the current file");
+ utimes_cmd.help = utimes_help;
+
+ add_command(&utimes_cmd);
+}
diff --git a/libxcmd/input.c b/libxcmd/input.c
index 5a7dce3..8aeb3b0 100644
--- a/libxcmd/input.c
+++ b/libxcmd/input.c
@@ -327,6 +327,28 @@ timestr(
}
/*
+ * Convert from a pair of arbitrary user strings into a timespec.
+ */
+
+int
+timespec_from_string(
+ const char * secs,
+ const char * nsecs,
+ struct timespec * ts)
+{
+ char* p;
+ if (!secs || !nsecs || !ts)
+ return 1;
+ ts->tv_sec = strtoull(secs, &p, 0);
+ if (*p)
+ return 1;
+ ts->tv_nsec = strtoull(nsecs, &p, 0);
+ if (*p)
+ return 1;
+ return 0;
+}
+
+/*
* Convert from arbitrary user strings into a numeric ID.
* If it's all numeric, we convert that inplace, else we do
* the name lookup, and return the found identifier.
diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8
index 2c56f09..9efb7b2 100644
--- a/man/man8/xfs_io.8
+++ b/man/man8/xfs_io.8
@@ -589,6 +589,16 @@ Copy data into the open file beginning at
Copy up to
.I length
bytes of data.
+.RE
+.PD
+.TP
+.BI utimes " atime_sec atime_nsec mtime_sec mtime_nsec"
+The utimes command changes the atime and mtime of the current file.
+sec uses UNIX timestamp notation and is the seconds elapsed since
+1970-01-01 00:00:00 UTC.
+nsec is the nanoseconds since the sec. This value needs to be in
+the range 0-999999999 with UTIME_NOW and UTIME_OMIT being exceptions.
+Each (sec, nsec) pair constitutes a single timestamp value.
.SH MEMORY MAPPED I/O COMMANDS
.TP
@@ -875,6 +885,7 @@ verbose output will be printed.
.BR fstatfs (2),
.BR fsync (2),
.BR ftruncate (2),
+.BR futimens (3),
.BR mmap (2),
.BR msync (2),
.BR open (2),
--
2.7.4