Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933151AbYFTUpm (ORCPT ); Fri, 20 Jun 2008 16:45:42 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1764281AbYFTUa3 (ORCPT ); Fri, 20 Jun 2008 16:30:29 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:40595 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1764272AbYFTUa0 (ORCPT ); Fri, 20 Jun 2008 16:30:26 -0400 Date: Fri, 20 Jun 2008 16:30:25 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Kernel development list cc: AntonioLin , David Vrabel Subject: Scatter-gather list constraints Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 780 Lines: 19 Is there any way to express the constraint that for a particular request queue, all members of a scatter-gather list (except the last) must be a multiple of a particular length? This question arises in connection with wireless USB mass-storage devices. The controller driver requires that all DMA segments in a transfer, other than the last one, have a multiple of 1024 bytes. But we're sometimes getting s-g lists where an element contains an odd number of 512-byte sectors, and of course it doesn't work. Thanks, Alan Stern -- 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/