Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 22 Jul 2002 23:02:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 22 Jul 2002 23:02:13 -0400 Received: from pizda.ninka.net ([216.101.162.242]:21930 "EHLO pizda.ninka.net") by vger.kernel.org with ESMTP id ; Mon, 22 Jul 2002 23:02:11 -0400 Date: Mon, 22 Jul 2002 19:54:26 -0700 (PDT) Message-Id: <20020722.195426.14578063.davem@redhat.com> To: thunder@ngforever.de Cc: linux-kernel@vger.kernel.org Subject: Re: Another DMA question From: "David S. Miller" In-Reply-To: References: X-Mailer: Mew version 2.1 on Emacs 21.1 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 931 Lines: 19 From: Thunder from the hill Date: Mon, 22 Jul 2002 20:38:51 -0600 (MDT) How can I get the _real_ address of a pci_map_single area, if needed? The thing bus_to_virt() did, basically. My problem is that I have code which changed the first byte of a buffer of stuff read via DMA, and I can't because the previous user did bus_to_virt() to get a pointer into that. I don't know how to get another pointer. After all the confusion, is the question clear? You need to keep track of the back translations yourself. See how the various net drivers do this by keeping a RX and TX ring of the SKB buffers mapped into the various rings. - 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/