From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35422) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dmMPn-0000Ab-N8 for qemu-devel@nongnu.org; Mon, 28 Aug 2017 11:57:28 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dmMPm-0001su-VP for qemu-devel@nongnu.org; Mon, 28 Aug 2017 11:57:27 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37514) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dmMPm-0001pm-Oq for qemu-devel@nongnu.org; Mon, 28 Aug 2017 11:57:26 -0400 Date: Mon, 28 Aug 2017 17:57:22 +0200 From: Cornelia Huck Message-ID: <20170828175722.0b54b59a.cohuck@redhat.com> In-Reply-To: <1503907487-2764-5-git-send-email-zyimin@linux.vnet.ibm.com> References: <1503907487-2764-1-git-send-email-zyimin@linux.vnet.ibm.com> <1503907487-2764-5-git-send-email-zyimin@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 4/4] s390x/pci: add iommu replay callback List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Yi Min Zhao Cc: qemu-devel@nongnu.org, borntraeger@de.ibm.com, pasic@linux.vnet.ibm.com, pmorel@linux.vnet.ibm.com, agraf@suse.de, richard.henderson@linaro.org On Mon, 28 Aug 2017 10:04:47 +0200 Yi Min Zhao wrote: > Let's introduce iommu replay callback for s390 pci iommu memory region. > Currently we don't need any dma mapping replay. So let it return > directly. This implementation will avoid meaningless loops calling > translation callback. > > Reviewed-by: Pierre Morel > Reviewed-by: Halil Pasic > Signed-off-by: Yi Min Zhao > --- > hw/s390x/s390-pci-bus.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c > index 9e1f7ff5c5..359509ccea 100644 > --- a/hw/s390x/s390-pci-bus.c > +++ b/hw/s390x/s390-pci-bus.c > @@ -407,6 +407,13 @@ static IOMMUTLBEntry s390_translate_iommu(IOMMUMemoryRegion *mr, hwaddr addr, > return ret; > } > > +static void s390_pci_iommu_replay(IOMMUMemoryRegion *iommu, > + IOMMUNotifier *notifier) > +{ > + /* we don't need iommu replay currently */ This really needs to be heavier on the _why_. My guess is that anything which would require replay goes through the rpcit instruction? > + return; > +} > + > static S390PCIIOMMU *s390_pci_get_iommu(S390pciState *s, PCIBus *bus, > int devfn) > { > @@ -1055,6 +1062,7 @@ static void s390_iommu_memory_region_class_init(ObjectClass *klass, void *data) > IOMMUMemoryRegionClass *imrc = IOMMU_MEMORY_REGION_CLASS(klass); > > imrc->translate = s390_translate_iommu; > + imrc->replay = s390_pci_iommu_replay; > } > > static const TypeInfo s390_iommu_memory_region_info = {