From: Neil Brown Subject: Re: Re: [PATCH] zerocopy NFS for 2.5.43 Date: Mon, 28 Oct 2002 09:46:53 +1100 Sender: nfs-admin@lists.sourceforge.net Message-ID: <15804.27869.374555.242999@notabene.cse.unsw.edu.au> References: <15797.63730.223181.75888@notabene.cse.unsw.edu.au> <20021025.185234.08315285.taka@valinux.co.jp> <15801.15328.866301.720864@notabene.cse.unsw.edu.au> <20021026.121150.74753877.taka@valinux.co.jp> <20021025234634.A26957@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Hirokazu Takahashi , nfs@lists.sourceforge.net Return-path: Received: from tone.orchestra.cse.unsw.edu.au ([129.94.242.28]) by usw-sf-list1.sourceforge.net with smtp (Exim 3.31-VA-mm2 #1 (Debian)) id 185wBX-00029s-00 for ; Sun, 27 Oct 2002 14:47:07 -0800 Received: From notabene.cse.unsw.edu.au ([129.94.233.204] == wireless-204.wireless.cse.unsw.EDU.AU) (for ) (for ) (for ) By tone With Smtp ; Mon, 28 Oct 2002 09:46:54 +1100 To: Benjamin LaHaise In-Reply-To: message from Benjamin LaHaise on Friday October 25 Errors-To: nfs-admin@lists.sourceforge.net List-Help: List-Post: List-Subscribe: , List-Id: Discussion of NFS under Linux development, interoperability, and testing. List-Unsubscribe: , List-Archive: On Friday October 25, bcrl@redhat.com wrote: > On Sat, Oct 26, 2002 at 12:11:50PM +0900, Hirokazu Takahashi wrote: > > OK. > > > > It's goot that you're implementing vfs_readv and vfs_writev which > > I've also realized it doesn't support aio yet. > > The aio methods are soon switching over to vectored operations for a > few reasons. It's likely that non-vectored methods will be gone soon. If you are introducing new 'vectored' operations, it would be nice if they work well for kernel-space as well as user-space. In the 'old days' before CONFIG_HIMEM, you could just oldfs = get_fs(); set_fs(KERNEL_DS); ...whatever.... set_fs(oldfs); to use kernel addresses. But with CONFIG_HIMEM the kernel often wants to work with "struct page *" instead of just a "void *", so this doesn't always work. It would be nice if you could pass in an 'actor' which for user-space access would call copy-to/from-user for kernel-space would do kmap/copy/kunmap Just a thought..... NeilBrown ------------------------------------------------------- This SF.net email is sponsored by: ApacheCon, November 18-21 in Las Vegas (supported by COMDEX), the only Apache event to be fully supported by the ASF. http://www.apachecon.com _______________________________________________ NFS maillist - NFS@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/nfs