From mboxrd@z Thu Jan 1 00:00:00 1970 In-reply-to: <20081022125140.GB826@shareable.org> (message from Jamie Lokier on Wed, 22 Oct 2008 13:51:40 +0100) Subject: Re: [patch] fs: improved handling of page and buffer IO errors References: <20081021112137.GB12329@wotan.suse.de> <20081021125915.GA26697@fogou.chygwyn.com> <20081021133814.GA26942@fogou.chygwyn.com> <20081021150948.GB28279@fogou.chygwyn.com> <20081022125140.GB826@shareable.org> Message-Id: From: Miklos Szeredi Date: Wed, 22 Oct 2008 16:08:56 +0200 Sender: owner-linux-mm@kvack.org Return-Path: To: jamie@shareable.org Cc: miklos@szeredi.hu, steve@chygwyn.com, npiggin@suse.de, akpm@linux-foundation.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org List-ID: On Wed, 22 Oct 2008, Jamie Lokier wrote: > So GFS goes to great lengths to ensure that read/write are coherent, > so are mmaps (writable or not), but _splice_ is not coherent in the > sense that it can send invalid but non-random data? :-) Spice is not coherent in any sense on any filesystem :) Your idea about COWing the page would be nice, and I think it may even be implementable. Currently the biggest problem with splice is the lack of users, we'd have to solve that first somehow. > Also, is there still a problem where the data is "valid" but part of > the page may have been zero'd by truncate, which is then transmitted > by splice? Yes. Miklos -- 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