From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:33740 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730783AbfFSIRM (ORCPT ); Wed, 19 Jun 2019 04:17:12 -0400 Date: Wed, 19 Jun 2019 10:17:09 +0200 From: Cornelia Huck Subject: Re: [RFC PATCH v1 2/5] vfio-ccw: Skip second copy of guest cp to host Message-ID: <20190619101709.2985e80e.cohuck@redhat.com> In-Reply-To: <20190618202352.39702-3-farman@linux.ibm.com> References: <20190618202352.39702-1-farman@linux.ibm.com> <20190618202352.39702-3-farman@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: Eric Farman Cc: Farhan Ali , Halil Pasic , linux-s390@vger.kernel.org, kvm@vger.kernel.org On Tue, 18 Jun 2019 22:23:49 +0200 Eric Farman wrote: > We already pinned/copied/unpinned 2K (256 CCWs) of guest memory > to the host space anchored off vfio_ccw_private. There's no need > to do that again once we have the length calculated, when we could > just copy the section we need to the "permanent" space for the I/O. > > Signed-off-by: Eric Farman > --- > drivers/s390/cio/vfio_ccw_cp.c | 10 +++------- > 1 file changed, 3 insertions(+), 7 deletions(-) Reviewed-by: Cornelia Huck