On Thu, Nov 03, 2016 at 04:43:57PM -0400, Theodore Ts'o wrote: > On Thu, Nov 03, 2016 at 09:48:27AM +1100, Dave Chinner wrote: > > > > We're going to need regression tests for this to ensure that it > > works properly and that we don't inadvertantly break it in future. > > Can you write some xfstests that exercise this functionality and > > validate that the mount behaviour, clamping and range limiting is > > working as intended? > > In order to have automated regression tests which are file system > independent, we need a way to query what are the timestamps that a > particular mounted file systme supports. We don't need that - we simply code it directly into the test infrastructure, like we've done for things like the maximum number of ACLs a filesystem supports (common/attr::_acl_get_max()). > The last option, which is admittedly ugly, would be to create an shell > function which knows how to figure out the max_timestamp and > min_timestamp by using the file system name and querying the > superblock using dumpe2fs, xfs_db, etc. Yup, precisely that. We shouldn't trust the kernel to tell us the correct thing to enable the test that tells us that thing is working correctly or not... > I'd argue for the last option because once we do get a programmtic way > to get the information via a system call such as fsinfo(2), we can > convert xfstests to use it, where as if we add an ioctl to return this > information, we'll have to support the ioctl forever. We have to support kernels that won't ever have something like fsinfo, so it has to be done the "ugly way". Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
