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. One approach would be to use fsinfo, which David Howells had been working on, but which has been bike-shedded to death for the last n years, and I'd hate to block this patch series behind a proposed new fsinfo(2) system call. Alternatively, we can just create a specialized ioctl to return that information which is non-ideal in other dimensions. 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. 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. Does this make sense? Any objections? Cheers, - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
