Some Linux filesystems might not fully support 64 bit timestamps [1],
which make some Linux specific tests to fail when they check for the
functionality.
This patch adds a new libsupport function, support_path_support_time64,
that returns whether the target file supports or not 64 bit timestamps.
The support is checked by issuing a utimensat and verifying both the
last access and last modification time against a statx call.
The tests that might fail are also adjusted to check the file support
as well:
$ dd if=/dev/zero of=loopbackfile.img bs=100M count=1
1+0 records in
1+0 records out
104857600 bytes (105 MB, 100 MiB) copied, 0,0589568 s, 1,8 GB/s
$ sudo losetup -fP loopbackfile.img
$ mkfs.xfs loopbackfile.img
meta-data=loopbackfile.img isize=512 agcount=4, agsize=6400 blks
= sectsz=512 attr=2, projid32bit=1
= crc=1 finobt=1, sparse=1, rmapbt=0
= reflink=1
data = bsize=4096 blocks=25600, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0, ftype=1
log =internal log bsize=4096 blocks=1368, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0
$ mkdir loopfs
$ sudo mount -o loop /dev/loop0 loopfs/
$ sudo chown -R azanella:azanella loopfs
$ TMPDIR=loopfs/ ./testrun.sh misc/tst-utimes
error: ../sysdeps/unix/sysv/linux/tst-utimes.c:55: File loopfs//utimesfECsK1 does not support 64-bit timestamps
[1] https://bugzilla.redhat.com/show_bug.cgi?id=1795576
