Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755959AbXJ0Qbc (ORCPT ); Sat, 27 Oct 2007 12:31:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752998AbXJ0QbZ (ORCPT ); Sat, 27 Oct 2007 12:31:25 -0400 Received: from nat-132.atmel.no ([80.232.32.132]:62711 "EHLO relay.atmel.no" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752389AbXJ0QbY convert rfc822-to-8bit (ORCPT ); Sat, 27 Oct 2007 12:31:24 -0400 Date: Sat, 27 Oct 2007 18:31:30 +0200 From: Haavard Skinnemoen To: "Robert P. J. Day" Cc: Linux Kernel Mailing List Subject: Re: sg_next() for struct scatterlist is confusing Message-ID: <20071027183130.0215e355@siona> In-Reply-To: References: Organization: Atmel X-Mailer: Claws Mail 2.10.0 (GTK+ 2.12.0; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 853 Lines: 20 On Sat, 27 Oct 2007 07:39:40 -0400 (EDT) "Robert P. J. Day" wrote: > note how the comment says that the next entry will "usually" be > sg+1, "but" not if it's actually a pointer. > > however, as i read the code above, sg is *always* incremented before > that testing. is that correct? am i just misreading something? or > could the comment have been a bit clearer? If it increments sg and finds a "chain" entry, it will follow it to the next sg array instead of just returning it. Which makes sense because the chain entry itself isn't a valid entry in the sg list. Håvard - 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/