Messages in this thread | | | Date | Tue, 30 Jan 2007 14:58:50 +0000 (GMT) | From | Anton Altaparmakov <> | Subject | Re: page_mkwrite caller is racy? |
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On Mon, 29 Jan 2007, Mark Fasheh wrote: > On Tue, Jan 30, 2007 at 12:14:24PM +1100, Nick Piggin wrote: > > This is another discussion, but do we want the page locked here? Or > > are the filesystems happy to exclude truncate themselves? > > No page lock please. Generally, Ocfs2 wants to order cluster locks outside > of page locks. Also, the sparse b-tree support I'm working on right now will > need to be able to allocate in ->page_mkwrite() which would become very > nasty if we came in with the page lock - aside from the additional cluster > locks taken, ocfs2 will want to zero some adjacent pages (because we support > atomic allocation up to 1 meg).
Ditto for NTFS. I will need to lock pages on both sides of the page for large volume cluster sizes thus I will have to drop the page lock if it is already taken so it might as well not be... Although I do not feel strongly about it. If the page is locked I will just drop the lock and then take it again. If possible to not have the page locked that would make my code a little easier/more efficient I expect...
Best regards,
Anton -- Anton Altaparmakov <aia21 at cam.ac.uk> (replace at with @) Unix Support, Computing Service, University of Cambridge, CB2 3QH, UK Linux NTFS maintainer, http://www.linux-ntfs.org/ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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