On Sun, 11 Jun 2006, Robin H. Johnson wrote: > On Sun, Jun 11, 2006 at 07:10:31PM +0100, Hugh Dickins wrote: > > > Perhaps we could devise a debug WARN_ON somewhere to check consistent > > granularity; but I don't have the ingenuity right now, and would need > > an additional superblock field or flag to not spam the logs horribly. > > Perhaps it's easier just to delete CURRENT_TIME, converting its users. > Yes, I'd agree that replacing CURRENT_TIME in filesystems with > current_fs_time should be worthwhile for all filesystems - That, > combined with your patch below to ensure they all use s_time_gran, > should ensure safety. > > A total removal of CURRENT_TIME wouldn't work, there are a few other > users besides setting [acm]times - however as above, we should be able > to kill it for all filesystems. Well, with CURRENT_TIME defined, for some time to come we're likely to have new filesystems going into the tree, copying old filesystems, using CURRENT_TIME but not setting s_time_gran. Undefining CURRENT_TIME and updating all its users would prevent that; but I don't intend to do so myself, and it certainly wouldn't be a 2.6.17 thing. > However CURRENT_TIME_SEC looks safe to convert, all of it's users are > filesystems. There should be no need to change that one at all: it was introduced to match the default s_time_gran of one second, so filesystems using it are declaring that they understand all this. Except for that odd stray usage in JFS. > > Setting that safety aside, the patch below (against 2.6.17-rc6) looks > > to me like all that's currently needed in mainline - but ecryptfs and > > reiser4 in the mm tree will also want fixing, and more discrepancies > > are sure to trickle in later. > I checked at well, and this does cover every filesystem I see in the > mainline. Oh, thanks a lot for double checking, that's a great help. > > If anyone thinks tmpfs is the most important to fix (I would think > > that, wouldn't I?), I can forward your fix to Linus ahead of the rest. > > Or if people agree the patch below is good, I can sign it off and send; > > or FS maintainers extract their own little parts. > I'd appreciate it tmpfs either of the fixes actually making it to > 2.6.17, there are a reasonable number of Gentoo users that use tmpfs as > temporary storage to compile stuff, and there's a long-standing argument > that tmpfs wasn't safe for that, due to this bug ;-). Right, I don't want Gentoo user impugning the safety of tmpfs: I'll send just your patch on to Linus; but divide the rest up to send to maintainers later (some of my choices may be wrong). Hugh - 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
