Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268564AbTGIThg (ORCPT ); Wed, 9 Jul 2003 15:37:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268566AbTGIThg (ORCPT ); Wed, 9 Jul 2003 15:37:36 -0400 Received: from pat.uio.no ([129.240.130.16]:38533 "EHLO pat.uio.no") by vger.kernel.org with ESMTP id S268564AbTGIThe (ORCPT ); Wed, 9 Jul 2003 15:37:34 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <16140.29271.365874.304823@charged.uio.no> Date: Wed, 9 Jul 2003 21:51:51 +0200 To: Jeff Garzik Cc: Trond Myklebust , Marc-Christian Petersen , Marcelo Tosatti , lkml Subject: Re: ->direct_IO API change in current 2.4 BK In-Reply-To: <20030709191739.GH15293@gtf.org> References: <20030709133109.A23587@infradead.org> <16140.24595.438954.609504@charged.uio.no> <200307092041.42608.m.c.p@wolk-project.de> <16140.25619.963866.474510@charged.uio.no> <20030709190531.GF15293@gtf.org> <16140.26693.72927.451259@charged.uio.no> <20030709191739.GH15293@gtf.org> X-Mailer: VM 7.07 under 21.4 (patch 8) "Honest Recruiter" XEmacs Lucid Reply-To: trond.myklebust@fys.uio.no From: Trond Myklebust X-MailScanner-Information: This message has been scanned for viruses/spam. Contact postmaster@uio.no if you have questions about this scanning. X-UiO-MailScanner: No virus found Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1350 Lines: 34 >>>>> " " == Jeff Garzik writes: > Having the stable API change, conditional on a define, is > really nasty and IMO will create maintenance and support > headaches down the line. I do not recall Linux VFS _ever_ > having a hook's definition conditional. We should not start > now... direct_IO() was precisely such a conditional hook definition. It appeared in 2.4.15, and anybody who does not check for KERNEL_HAS_O_DIRECT is not backward compatible. To comment further: There is at least one example I can think of which was exactly equivalent to the proposed change, namely the redefinition of the filldir_t type in 2.4.9. It was admittedly not documented using a define... Note: We could at the same time replace the name direct_IO() with direct_IO2() (that has several precedents). There are currently only a small number of filesystems that provide O_DIRECT, and converting them all is (as has been pointed out before) trivial... The problem with read_inode2() was rather that it overloaded the the existing iget4() interface... Cheers, Trond - 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/