From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 41kw9R2Jr1zDqCD for ; Tue, 7 Aug 2018 10:18:51 +1000 (AEST) Message-ID: <53554e339b334b47d5822fb5219d5c878674b33c.camel@kernel.crashing.org> Subject: Re: [RFC 0/4] Virtio uses DMA API for all devices From: Benjamin Herrenschmidt To: "Michael S. Tsirkin" Cc: Christoph Hellwig , Will Deacon , Anshuman Khandual , virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, aik@ozlabs.ru, robh@kernel.org, joe@perches.com, elfring@users.sourceforge.net, david@gibson.dropbear.id.au, jasowang@redhat.com, mpe@ellerman.id.au, linuxram@us.ibm.com, haren@linux.vnet.ibm.com, paulus@samba.org, srikar@linux.vnet.ibm.com, robin.murphy@arm.com, jean-philippe.brucker@arm.com, marc.zyngier@arm.com Date: Tue, 07 Aug 2018 10:18:07 +1000 In-Reply-To: <20180807024503-mutt-send-email-mst@kernel.org> References: <20180803220443-mutt-send-email-mst@kernel.org> <051fd78e15595b414839fa8f9d445b9f4d7576c6.camel@kernel.crashing.org> <20180805031046-mutt-send-email-mst@kernel.org> <20180806164106-mutt-send-email-mst@kernel.org> <20180806233024-mutt-send-email-mst@kernel.org> <0967fc30001323e6e38ed12c8dba8ee3d1aa13f5.camel@kernel.crashing.org> <20180807002857-mutt-send-email-mst@kernel.org> <93518075238a07e9f011774d89bdc652c083f1ba.camel@kernel.crashing.org> <20180807024503-mutt-send-email-mst@kernel.org> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, 2018-08-07 at 02:45 +0300, Michael S. Tsirkin wrote: > > OK well, assuming Christoph can solve the direct case in a way that > > also work for the virtio !iommu case, we still want some bit of logic > > somewhere that will "switch" to swiotlb based ops if the DMA mask is > > limited. > > > > You mentioned an RFC for that ? Do you happen to have a link ? > > No but Christoph did I think. Ok I missed that, sorry, I'll dig it out. Thanks. Cheers, Ben.