LOLi 99834d1950 Fix truncate(2) mtime and ctime handling ... On Linux, ftruncate(2) always changes the file timestamps, even if the file size is not changed. However, in case of a successfull truncate(2), the timestamps are updated only if the file size changes. This translates to the VFS calling the ZFS Posix Layer "setattr" function (zpl_setattr) with ATTR_MTIME and ATTR_CTIME unconditionally set on the iattr mask only when doing a ftruncate(2), while the truncate(2) is left to the filesystem implementation to be dealt with. This behaviour is consistent with POSIX:2004/SUSv3 specifications where there's no explicit requirement for file size changes to update the timestamps only for ftruncate(2): http://pubs.opengroup.org/onlinepubs/009695399/functions/truncate.html http://pubs.opengroup.org/onlinepubs/009695399/functions/ftruncate.html This has been later updated in POSIX:2008/SUSv4 where, for both truncate(2)/ftruncate(2), there's no mention of this size change requirement: http://austingroupbugs.net/view.php?id=489 http://pubs.opengroup.org/onlinepubs/9699919799/functions/truncate.html http://pubs.opengroup.org/onlinepubs/9699919799/functions/ftruncate.html Unfortunately the Linux VFS is still calling into the ZPL without ATTR_MTIME/ATTR_CTIME set in the truncate(2) case: we fix this by explicitly updating the timestamps when detecting the ATTR_SIZE bit, which is always set in do_truncate(), on the iattr mask. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: loli10K <ezomori.nozomu@gmail.com> Closes #6811 Closes #6819		2017-11-13 09:24:26 -08:00
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linux.run	Fix truncate(2) mtime and ctime handling	2017-11-13 09:24:26 -08:00
Makefile.am	Add the ZFS Test Suite	2016-03-16 13:46:16 -07:00
perf-regression.run	Provide tags in perf-regression.run	2017-11-07 15:06:27 -08:00