Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932633AbbD0KxD (ORCPT ); Mon, 27 Apr 2015 06:53:03 -0400 Received: from e06smtp13.uk.ibm.com ([195.75.94.109]:33969 "EHLO e06smtp13.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932557AbbD0KxA (ORCPT ); Mon, 27 Apr 2015 06:53:00 -0400 Message-ID: <553E1506.5080206@de.ibm.com> Date: Mon, 27 Apr 2015 12:52:54 +0200 From: Christian Borntraeger User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: Michael Mueller CC: qemu-devel@nongnu.org, kvm@vger.kernel.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, Eduardo Habkost , Gleb Natapov , Alexander Graf , Daniel Hansel , "Jason J. Herne" , Cornelia Huck , Paolo Bonzini , Richard Henderson , Andreas Faerber Subject: Re: [Qemu-devel] [PATCH v5 11/17] target-s390x: Add KVM VM attribute interface for S390 CPU models References: <1428933396-37887-1-git-send-email-mimu@linux.vnet.ibm.com> <1428933396-37887-12-git-send-email-mimu@linux.vnet.ibm.com> <553DF033.1060405@de.ibm.com> <20150427114353.0386c3eb@bee> In-Reply-To: <20150427114353.0386c3eb@bee> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15042710-0013-0000-0000-000003CA7F82 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1456 Lines: 37 Am 27.04.2015 um 11:43 schrieb Michael Mueller: > On Mon, 27 Apr 2015 10:15:47 +0200 > Christian Borntraeger wrote: > >> Am 13.04.2015 um 15:56 schrieb Michael Mueller: >> [...] >>> +static int cpu_model_get(KVMState *s, uint64_t attr, uint64_t addr) >>> +{ >>> + int rc = -ENOSYS; >>> + struct kvm_device_attr dev_attr = { >>> + .group = KVM_S390_VM_CPU_MODEL, >>> + .attr = attr, >>> + .addr = addr, >> >> Would it make sense to do the cast here.... > > cpu_model_get/set() is used to handle both attributes, > KVM_S390_VM_CPU_MACHINE and KVM_S390_VM_CPU_PROCESSOR. > Both require a different type in the signature, (S390ProcessorProps*) > and (S390MachineProps*). Adding both as parameters seems to be odd > and would require additionally logic in the function. > Thus I think doing the cast outside is just the right thing to do. So what about a void pointer then as parameter? I prefer a pointer for qemu process memory over uint64_t as part of the function interface. This makes it somewhat clearer that this is an address within QEMU. Both ways will certainly work, though. Conny, I guess you will pick up the patches. Any preference? Christian -- 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/