Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753528AbaLAMVD (ORCPT ); Mon, 1 Dec 2014 07:21:03 -0500 Received: from e06smtp10.uk.ibm.com ([195.75.94.106]:42454 "EHLO e06smtp10.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753268AbaLAMVC (ORCPT ); Mon, 1 Dec 2014 07:21:02 -0500 Date: Mon, 1 Dec 2014 13:20:51 +0100 From: Cornelia Huck To: "Michael S. Tsirkin" Cc: linux-kernel@vger.kernel.org, David Miller , rusty@au1.ibm.com, nab@linux-iscsi.org, pbonzini@redhat.com, thuth@linux.vnet.ibm.com, dahi@linux.vnet.ibm.com, Jason Wang , kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org Subject: Re: [PATCH v7 30/46] vhost/net: force len for TX to host endian Message-ID: <20141201132051.4ab028d9.cornelia.huck@de.ibm.com> In-Reply-To: <1417359787-10138-31-git-send-email-mst@redhat.com> References: <1417359787-10138-1-git-send-email-mst@redhat.com> <1417359787-10138-31-git-send-email-mst@redhat.com> Organization: IBM Deutschland Research & Development GmbH Vorsitzende des Aufsichtsrats: Martina Koederitz =?UTF-8?B?R2VzY2jDpGZ0c2bDvGhydW5nOg==?= Dirk Wittkopp Sitz der Gesellschaft: =?UTF-8?B?QsO2Ymxpbmdlbg==?= Registergericht: Amtsgericht Stuttgart, HRB 243294 X-Mailer: Claws Mail 3.8.0 (GTK+ 2.24.10; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14120112-0041-0000-0000-00000250ED59 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 30 Nov 2014 17:11:44 +0200 "Michael S. Tsirkin" wrote: > vhost/net keeps a copy of some used ring but (ab)uses length > field for internal house-keeping. This works because > for tx used length is always 0. > Suppress sparse errors: we use native endian-ness internally but never > expose it to guest. I admit that I find this patch description hard to read :) "vhost/net keeps a copy of the used ring in host memory but (ab)uses the length field for internal house-keeping. This works because the length in the used ring for tx is always 0. In order to suppress sparse errors, we need to force native endianness." ? > > Signed-off-by: Michael S. Tsirkin > Reviewed-by: Jason Wang > --- > drivers/vhost/net.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c > index 8dae2f7..dce5c58 100644 > --- a/drivers/vhost/net.c > +++ b/drivers/vhost/net.c > @@ -48,15 +48,15 @@ MODULE_PARM_DESC(experimental_zcopytx, "Enable Zero Copy TX;" > * status internally; used for zerocopy tx only. > */ > /* Lower device DMA failed */ > -#define VHOST_DMA_FAILED_LEN 3 > +#define VHOST_DMA_FAILED_LEN ((__force __virtio32)3) > /* Lower device DMA done */ > -#define VHOST_DMA_DONE_LEN 2 > +#define VHOST_DMA_DONE_LEN ((__force __virtio32)2) > /* Lower device DMA in progress */ > -#define VHOST_DMA_IN_PROGRESS 1 > +#define VHOST_DMA_IN_PROGRESS ((__force __virtio32)1) > /* Buffer unused */ > -#define VHOST_DMA_CLEAR_LEN 0 > +#define VHOST_DMA_CLEAR_LEN ((__force __virtio32)0) > > -#define VHOST_DMA_IS_DONE(len) ((len) >= VHOST_DMA_DONE_LEN) > +#define VHOST_DMA_IS_DONE(len) ((__force u32)(len) >= (__force u32)VHOST_DMA_DONE_LEN) > > enum { > VHOST_NET_FEATURES = VHOST_FEATURES | -- 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/