From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:50836 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726509AbfFUOeY (ORCPT ); Fri, 21 Jun 2019 10:34:24 -0400 From: Cornelia Huck Subject: [PULL 11/14] vfio-ccw: Skip second copy of guest cp to host Date: Fri, 21 Jun 2019 16:33:52 +0200 Message-Id: <20190621143355.29175-12-cohuck@redhat.com> In-Reply-To: <20190621143355.29175-1-cohuck@redhat.com> References: <20190621143355.29175-1-cohuck@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: Heiko Carstens , Vasily Gorbik , Christian Borntraeger Cc: Farhan Ali , Eric Farman , Halil Pasic , linux-s390@vger.kernel.org, kvm@vger.kernel.org, Cornelia Huck From: Eric Farman 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 Message-Id: <20190618202352.39702-3-farman@linux.ibm.com> Reviewed-by: Cornelia Huck Reviewed-by: Farhan Ali Signed-off-by: Cornelia Huck --- drivers/s390/cio/vfio_ccw_cp.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c index f358502376be..37d513e86530 100644 --- a/drivers/s390/cio/vfio_ccw_cp.c +++ b/drivers/s390/cio/vfio_ccw_cp.c @@ -444,7 +444,7 @@ static int ccwchain_loop_tic(struct ccwchain *chain, static int ccwchain_handle_ccw(u32 cda, struct channel_program *cp) { struct ccwchain *chain; - int len, ret; + int len; /* Copy the chain from cda to cp, and count the CCWs in it */ len = ccwchain_calc_length(cda, cp); @@ -457,12 +457,8 @@ static int ccwchain_handle_ccw(u32 cda, struct channel_program *cp) return -ENOMEM; chain->ch_iova = cda; - /* Copy the new chain from user. */ - ret = copy_ccw_from_iova(cp, chain->ch_ccw, cda, len); - if (ret) { - ccwchain_free(chain); - return ret; - } + /* Copy the actual CCWs into the new chain */ + memcpy(chain->ch_ccw, cp->guest_cp, len * sizeof(struct ccw1)); /* Loop for tics on this new chain. */ return ccwchain_loop_tic(chain, cp); -- 2.20.1