From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [RFC/PATCH 4/5] loop: execute in place (V2) Date: Wed, 18 May 2005 15:28:49 +0100 Message-ID: <20050518142849.GC23162@infradead.org> References: <1116422644.2202.1.camel@cotte.boeblingen.de.ibm.com> <1116424432.2202.19.camel@cotte.boeblingen.de.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, schwidefsky@de.ibm.com, akpm@osdl.org Return-path: To: cotte@freenet.de Content-Disposition: inline In-Reply-To: <1116424432.2202.19.camel@cotte.boeblingen.de.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Wed, May 18, 2005 at 03:53:52PM +0200, Carsten Otte wrote: > [RFC/PATCH 4/5] loop: execute in place (V2) > The old loop driver in 2.6.11. used the readpage/writepage aops to > transfer data. Now loop can also use read/write and direct_IO on the > file if readpage/writepage are not available. Unlike the old 2.6.11. > version, today's loop driver does work with files that do not have > readpage/writepage. Threrefore, this patch is optional. > This patch adds one more transport method to loop that uses the new > address space operation get_xip_page if available. > > This patch is unchanged from previous version. This should be ifdef'ed to avoid bloat for non-XIP builds. Or just be dropped completely. How much difference does it make over read/write and where does loop performance matter?