From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by dpdk.org (Postfix) with ESMTP id ECD4B8E01; Mon, 8 Jan 2018 17:48:53 +0100 (CET) Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 143FA7EBD5; Mon, 8 Jan 2018 16:48:53 +0000 (UTC) Received: from [10.36.112.43] (ovpn-112-43.ams2.redhat.com [10.36.112.43]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0F9E05D6A2; Mon, 8 Jan 2018 16:48:47 +0000 (UTC) From: Maxime Coquelin To: Stephen Hemminger Cc: dev@dpdk.org, stable@dpdk.org, jianfeng.tan@intel.com, santosh.shukla@caviumnetworks.com, anatoly.burakov@intel.com, thomas@monjalon.net, peterx@redhat.com References: <20180108135127.25869-1-maxime.coquelin@redhat.com> <20180108073841.43c15072@xeon-e3> <62b32cc7-68a8-806c-d4fb-e15addbeabfb@redhat.com> Message-ID: <2ee389ac-1915-d9dd-01aa-0447b4f0008f@redhat.com> Date: Mon, 8 Jan 2018 17:48:46 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.5.0 MIME-Version: 1.0 In-Reply-To: <62b32cc7-68a8-806c-d4fb-e15addbeabfb@redhat.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Mon, 08 Jan 2018 16:48:53 +0000 (UTC) Subject: Re: [dpdk-dev] [PATCH] bus/pci: forbid VA as IOVA mode if IOMMU address width too small X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 08 Jan 2018 16:48:54 -0000 On 01/08/2018 04:54 PM, Maxime Coquelin wrote: > > > On 01/08/2018 04:38 PM, Stephen Hemminger wrote: >> On Mon,  8 Jan 2018 14:51:27 +0100 >> Maxime Coquelin wrote: >> >>> +static inline bool >>> +pci_one_device_iommu_support_va(struct rte_pci_device *dev) >>> +{ >>> +#if defined(RTE_ARCH_PPC_64) >>> +    return false; >>> +#elif defined(RTE_ARCH_X86) >>> + >> >> The cleaner way to handle this kind of ifdef is: >> >> #ifdef RTE_ARCH_X86 >> static bool >> pci_one_device_iommu_support_va(struct rte_pci_device *dev) >> { >> .... >> } >> #elif defined(RTE_ARCH_PPC_64) >> static inline bool >> pci_one_device_iommu_support_va(struct rte_pci_device *dev) >> { >>     return false; >> } >> #endif > > Ok, thanks. I do this in v2. > >> What about AMD64? > > I haven't checked AMD64 spec yet. From AMD IOMMU spec (see [0], page 178), the only supported Guest Virtual Address size is 48bits, so above the 47 bits of user VA on x86. So in this regard, AMD IOMMU is compatible with using VA as IOVA. Cheers, Maxime [0]: https://support.amd.com/TechDocs/48882_IOMMU.pdf