From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [patch][rfc] mm: new address space calls Date: Sat, 28 Feb 2009 18:19:56 -0500 Message-ID: <20090228231956.GA11191@infradead.org> References: <20090225104839.GG22785@wotan.suse.de> <1235595597.32346.77.camel@think.oraclecorp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Nick Piggin , Linux Memory Management List , linux-fsdevel@vger.kernel.org To: Chris Mason Return-path: Content-Disposition: inline In-Reply-To: <1235595597.32346.77.camel@think.oraclecorp.com> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org On Wed, Feb 25, 2009 at 03:59:57PM -0500, Chris Mason wrote: > One problem I have with the btrfs extent state code is that I might > choose to release the extent state in releasepage, but the VM might not > choose to free the page. So I've got an up to date page without any of > the rest of my state. > > Which of these ops covers that? ;) I'd love to help better document the > requirements for these callbacks, I find it confusing every time. releasepage has also another problem. It only gets called after discard_buffer discarded lots of valuable information from the buffers, which gets XFS into really bad trouble as that drops information if there is a delalloc extent. I'd really like to see some major overhaul in that area, and that also extende to documentation (or just naming, why is block_invalidatepage calling into a method called ->releasepage, but there also is a ->invalidatepage that gets called from truncate*page routines..) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org