From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753163AbcBAQLq (ORCPT ); Mon, 1 Feb 2016 11:11:46 -0500 Received: from bombadil.infradead.org ([198.137.202.9]:42524 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752019AbcBAQLo (ORCPT ); Mon, 1 Feb 2016 11:11:44 -0500 Message-ID: <1454343091.4788.0.camel@infradead.org> Subject: Re: [PATCH v5 04/10] vring: Introduce vring_use_dma_api() From: David Woodhouse To: Andy Lutomirski , "Michael S. Tsirkin" Cc: Andy Lutomirski , Benjamin Herrenschmidt , "linux-kernel@vger.kernel.org" , "David S. Miller" , sparclinux@vger.kernel.org, Joerg Roedel , Christian Borntraeger , Cornelia Huck , Sebastian Ott , Paolo Bonzini , Christoph Hellwig , KVM , Martin Schwidefsky , linux-s390 , Linux Virtualization , David Vrabel , Stefano Stabellini , "xen-devel@lists.xenproject.org" Date: Mon, 01 Feb 2016 16:11:31 +0000 In-Reply-To: References: <1454325723.133285.285.camel@infradead.org> <20160201133556-mutt-send-email-mst@redhat.com> Content-Type: multipart/signed; micalg="sha-1"; protocol="application/x-pkcs7-signature"; boundary="=-GLlXc2CFQ6OlAfw9L6e0" X-Mailer: Evolution 3.18.3 (3.18.3-1.fc23) Mime-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-GLlXc2CFQ6OlAfw9L6e0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, 2016-02-01 at 07:39 -0800, Andy Lutomirski wrote: >=20 > >> Could we have an arch_vring_eschew_dma_api(dev) function which the > >> affected architectures could provide (as a prelude to fixing it so tha= t > >> the DMA API does the right thing for *itself*)? > > > > I'm fine with this. >=20 > I modified vring_use_dma_api to take a vring_virtqueue* parameter to > make this easier. >=20 > I'm a bit torn here.=C2=A0 I want to get the mechanism and the Xen part i= n, > and there's unlikely to be much debate on those as a matter of > principle.=C2=A0 I'd also like to flip as many arches over as possible, b= ut > that could be trickier.=C2=A0 Let me mull over this. Let's queue the arch_vring_eschew_dma_api() thing up after this first batch, and not hold it up any further. --=20 David Woodhouse Open Source Technology Centre David.Woodhouse@intel.com Intel Corporation --=-GLlXc2CFQ6OlAfw9L6e0 Content-Type: application/x-pkcs7-signature; name="smime.p7s" Content-Disposition: attachment; filename="smime.p7s" Content-Transfer-Encoding: base64 MIAGCSqGSIb3DQEHAqCAMIACAQExCzAJBgUrDgMCGgUAMIAGCSqGSIb3DQEHAQAAoIISjjCCBicw ggUPoAMCAQICAw3vNzANBgkqhkiG9w0BAQUFADCBjDELMAkGA1UEBhMCSUwxFjAUBgNVBAoTDVN0 YXJ0Q29tIEx0ZC4xKzApBgNVBAsTIlNlY3VyZSBEaWdpdGFsIENlcnRpZmljYXRlIFNpZ25pbmcx ODA2BgNVBAMTL1N0YXJ0Q29tIENsYXNzIDEgUHJpbWFyeSBJbnRlcm1lZGlhdGUgQ2xpZW50IENB MB4XDTE1MDUwNTA5NDM0MVoXDTE2MDUwNTA5NTMzNlowQjEcMBoGA1UEAwwTZHdtdzJAaW5mcmFk ZWFkLm9yZzEiMCAGCSqGSIb3DQEJARYTZHdtdzJAaW5mcmFkZWFkLm9yZzCCASIwDQYJKoZIhvcN AQEBBQADggEPADCCAQoCggEBAMkbm9kPbx1j/X4RVyf/pPKSYwelcco69TvnQQbKM8m8xkWjXJI1 jpJ1jMaGUZGFToINMSZi7lZawUozudWbXSKy1SikENSTJHffsdRAIlsp+hR8vWvjsKUry6sEdqPG 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