From owner-freebsd-hackers Mon Aug 14 11:16:21 2000 Delivered-To: freebsd-hackers@freebsd.org Received: from hotmail.com (f89.pav1.hotmail.com [64.4.31.89]) by hub.freebsd.org (Postfix) with ESMTP id DD2E237BF3C for ; Mon, 14 Aug 2000 11:16:14 -0700 (PDT) (envelope-from biffey@hotmail.com) Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Mon, 14 Aug 2000 11:16:09 -0700 Received: from 209.213.222.214 by pv1fd.pav1.hotmail.msn.com with HTTP; Mon, 14 Aug 2000 GMT X-Originating-IP: [209.213.222.214] From: "Bill Clinton" To: freebsd-hackers@freebsd.org Subject: dma to userland address Date: Mon, 14 Aug 2000 18:16:09 GMT Mime-Version: 1.0 Content-Type: text/plain; format=flowed Message-ID: X-OriginalArrivalTime: 14 Aug 2000 18:16:09.0986 (UTC) FILETIME=[B8C02E20:01C0061B] Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG lets say, hypothetically, that i have an ioctl interface to my device driver that takes a buffer that looks something like: struct { int length; char *buf; } mystruct; and lets say, hypothetically, that i wanted to dma directly to/from 'buf'. how would i do that? i've tried doing vtophys on buf, but that doesn't seem to work. i've tried doing vtophys on a kernel-allocated block and the mmapping it through /dev/mem in userland, but that doesn't seem to work either (this may have a bug, though - it worked under linux, but was about 10x slower than just leaving the kernel/user copy in there). so what am i missing here? - j ________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message