From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rusty Russell Subject: Re: [RFC virtio-next 0/4] Introduce CAIF Virtio and reversed Vrings Date: Thu, 01 Nov 2012 18:11:35 +1030 Message-ID: <87wqy54vo0.fsf@rustcorp.com.au> References: <1351723614-4145-1-git-send-email-sjur@brendeland.net> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <1351723614-4145-1-git-send-email-sjur@brendeland.net> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org Cc: "Michael S. Tsirkin" , netdev@vger.kernel.org, Linus Walleij , dmitry.tarnyagin@stericsson.com, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, sjur@brendeland.net List-Id: virtualization@lists.linuxfoundation.org U2p1ciBCcsOmbmRlbGFuZCA8c2p1ckBicmVuZGVsYW5kLm5ldD4gd3JpdGVzOgo+IFplcm8tQ29w eSBkYXRhIHRyYW5zcG9ydCBvbiB0aGUgbW9kZW0gaXMgcHJpbWFyeSBnb2FsIGZvciBDQUlGIFZp cnRpby4KPiBJbiBvcmRlciB0byBhY2hpZXZlIFplcm8tQ29weSB0aGUgZGlyZWN0aW9uIG9mIHRo ZSBWaXJ0aW8gcmluZ3MgYXJlCj4gZmxpcHBlZCBpbiB0aGUgUlggZGlyZWN0aW9uLiBTbyB3ZSBo YXZlIGltcGxlbWVudGVkIHRoZSBWaXJ0aW8KPiBhY2Nlc3MtZnVuY3Rpb24gc2ltaWxhciB0byB3 aGF0IGlzIGZvdW5kIGluIHZob3N0LmMuCgpTbywgdGhpcyBhZGRzIGFub3RoZXIgaG9zdC1zaWRl IHZpcnRxdWV1ZSBpbXBsZW1lbnRhdGlvbi4KCkNhbiB3ZSBjb21iaW5lIHRoZW0gdG9nZXRoZXIg Y29udmVuaWVudGx5PyAgWW91IHB1bGxlZCBvdXQgbW9yZSBzdHVmZgppbnRvIHZyaW5nLmggd2hp Y2ggaXMgYSBzdGFydCwgYnV0IGl0J3MgYSBiaXQgb3ZlcmxvYWRlZC4KClBlcmhhcHMgd2Ugc2hv dWxkIHNlcGFyYXRlIHRoZSBjb21tb24gZmllbGRzIGludG8gc3RydWN0IHZyaW5nLCBhbmQgdXNl Cml0IHRvIGJ1aWxkOgoKICAgICAgICBzdHJ1Y3QgdnJpbmdfZ3Vlc3QgewogICAgICAgICAgICAg ICAgc3RydWN0IHZyaW5nIHZyOwogICAgICAgICAgICAgICAgdTE2IGxhc3RfdXNlZF9pZHg7CiAg ICAgICAgfTsKCiAgICAgICAgc3RydWN0IHZyaW5nX2hvc3QgewogICAgICAgICAgICAgICAgc3Ry dWN0IHZyaW5nIHZyOwogICAgICAgICAgICAgICAgdTE2IGxhc3RfYXZhaWxfaWR4OwogICAgICAg IH07CgpJIGhhdmVuJ3QgbG9va2VkIGNsb3NlbHkgYXQgdmhvc3QgdG8gc2VlIHdoYXQgaXQgd2Fu dHMsIGJ1dCBJIHdvdWxkCnRoaW5rIHdlIGNvdWxkIHNoYXJlIG1vcmUgY29kZS4KCkNoZWVycywK UnVzdHkuCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fClZp cnR1YWxpemF0aW9uIG1haWxpbmcgbGlzdApWaXJ0dWFsaXphdGlvbkBsaXN0cy5saW51eC1mb3Vu ZGF0aW9uLm9yZwpodHRwczovL2xpc3RzLmxpbnV4Zm91bmRhdGlvbi5vcmcvbWFpbG1hbi9saXN0 aW5mby92aXJ0dWFsaXphdGlvbg== From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754648Ab2KAHnM (ORCPT ); Thu, 1 Nov 2012 03:43:12 -0400 Received: from ozlabs.org ([203.10.76.45]:56908 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754212Ab2KAHnJ convert rfc822-to-8bit (ORCPT ); Thu, 1 Nov 2012 03:43:09 -0400 From: Rusty Russell To: Sjur =?utf-8?Q?Br=C3=A6ndeland?= Cc: "Michael S. Tsirkin" , Linus Walleij , Ohad Ben-Cohen , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, virtualization@lists.linux-foundation.org, sjur@brendeland.net, dmitry.tarnyagin@stericsson.com Subject: Re: [RFC virtio-next 0/4] Introduce CAIF Virtio and reversed Vrings In-Reply-To: <1351723614-4145-1-git-send-email-sjur@brendeland.net> References: <1351723614-4145-1-git-send-email-sjur@brendeland.net> User-Agent: Notmuch/0.14 (http://notmuchmail.org) Emacs/23.4.1 (i686-pc-linux-gnu) Date: Thu, 01 Nov 2012 18:11:35 +1030 Message-ID: <87wqy54vo0.fsf@rustcorp.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Sjur Brændeland writes: > Zero-Copy data transport on the modem is primary goal for CAIF Virtio. > In order to achieve Zero-Copy the direction of the Virtio rings are > flipped in the RX direction. So we have implemented the Virtio > access-function similar to what is found in vhost.c. So, this adds another host-side virtqueue implementation. Can we combine them together conveniently? You pulled out more stuff into vring.h which is a start, but it's a bit overloaded. Perhaps we should separate the common fields into struct vring, and use it to build: struct vring_guest { struct vring vr; u16 last_used_idx; }; struct vring_host { struct vring vr; u16 last_avail_idx; }; I haven't looked closely at vhost to see what it wants, but I would think we could share more code. Cheers, Rusty. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rusty Russell Subject: Re: [RFC virtio-next 0/4] Introduce CAIF Virtio and reversed Vrings Date: Thu, 01 Nov 2012 18:11:35 +1030 Message-ID: <87wqy54vo0.fsf@rustcorp.com.au> References: <1351723614-4145-1-git-send-email-sjur@brendeland.net> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Cc: "Michael S. Tsirkin" , netdev@vger.kernel.org, Linus Walleij , dmitry.tarnyagin@stericsson.com, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, sjur@brendeland.net To: Sjur =?utf-8?Q?Br=C3=A6ndeland?= Return-path: In-Reply-To: <1351723614-4145-1-git-send-email-sjur@brendeland.net> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org List-Id: netdev.vger.kernel.org U2p1ciBCcsOmbmRlbGFuZCA8c2p1ckBicmVuZGVsYW5kLm5ldD4gd3JpdGVzOgo+IFplcm8tQ29w eSBkYXRhIHRyYW5zcG9ydCBvbiB0aGUgbW9kZW0gaXMgcHJpbWFyeSBnb2FsIGZvciBDQUlGIFZp cnRpby4KPiBJbiBvcmRlciB0byBhY2hpZXZlIFplcm8tQ29weSB0aGUgZGlyZWN0aW9uIG9mIHRo ZSBWaXJ0aW8gcmluZ3MgYXJlCj4gZmxpcHBlZCBpbiB0aGUgUlggZGlyZWN0aW9uLiBTbyB3ZSBo YXZlIGltcGxlbWVudGVkIHRoZSBWaXJ0aW8KPiBhY2Nlc3MtZnVuY3Rpb24gc2ltaWxhciB0byB3 aGF0IGlzIGZvdW5kIGluIHZob3N0LmMuCgpTbywgdGhpcyBhZGRzIGFub3RoZXIgaG9zdC1zaWRl IHZpcnRxdWV1ZSBpbXBsZW1lbnRhdGlvbi4KCkNhbiB3ZSBjb21iaW5lIHRoZW0gdG9nZXRoZXIg Y29udmVuaWVudGx5PyAgWW91IHB1bGxlZCBvdXQgbW9yZSBzdHVmZgppbnRvIHZyaW5nLmggd2hp Y2ggaXMgYSBzdGFydCwgYnV0IGl0J3MgYSBiaXQgb3ZlcmxvYWRlZC4KClBlcmhhcHMgd2Ugc2hv dWxkIHNlcGFyYXRlIHRoZSBjb21tb24gZmllbGRzIGludG8gc3RydWN0IHZyaW5nLCBhbmQgdXNl Cml0IHRvIGJ1aWxkOgoKICAgICAgICBzdHJ1Y3QgdnJpbmdfZ3Vlc3QgewogICAgICAgICAgICAg ICAgc3RydWN0IHZyaW5nIHZyOwogICAgICAgICAgICAgICAgdTE2IGxhc3RfdXNlZF9pZHg7CiAg ICAgICAgfTsKCiAgICAgICAgc3RydWN0IHZyaW5nX2hvc3QgewogICAgICAgICAgICAgICAgc3Ry dWN0IHZyaW5nIHZyOwogICAgICAgICAgICAgICAgdTE2IGxhc3RfYXZhaWxfaWR4OwogICAgICAg IH07CgpJIGhhdmVuJ3QgbG9va2VkIGNsb3NlbHkgYXQgdmhvc3QgdG8gc2VlIHdoYXQgaXQgd2Fu dHMsIGJ1dCBJIHdvdWxkCnRoaW5rIHdlIGNvdWxkIHNoYXJlIG1vcmUgY29kZS4KCkNoZWVycywK UnVzdHkuCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fClZp cnR1YWxpemF0aW9uIG1haWxpbmcgbGlzdApWaXJ0dWFsaXphdGlvbkBsaXN0cy5saW51eC1mb3Vu ZGF0aW9uLm9yZwpodHRwczovL2xpc3RzLmxpbnV4Zm91bmRhdGlvbi5vcmcvbWFpbG1hbi9saXN0 aW5mby92aXJ0dWFsaXphdGlvbg==