From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752746AbeDJLEu (ORCPT ); Tue, 10 Apr 2018 07:04:50 -0400 Received: from mail-lf0-f46.google.com ([209.85.215.46]:34354 "EHLO mail-lf0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751943AbeDJLEs (ORCPT ); Tue, 10 Apr 2018 07:04:48 -0400 X-Google-Smtp-Source: AIpwx48sCijvR45PolkiBuo1hu25sR6IRea7tBAo5KyGWIHDl+daoak8WhsCej7P0eyNxQbRgIZPig== Subject: Re: [Xen-devel] [RFC, v2, 1/9] hyper_dmabuf: initial upload of hyper_dmabuf drv core framework To: Julien Grall , Dongwon Kim , linux-kernel@vger.kernel.org, linaro-mm-sig@lists.linaro.org, xen-devel@lists.xenproject.org Cc: mateuszx.potrola@intel.com, dri-devel@lists.freedesktop.org References: <20180214015008.9513-2-dongwon.kim@intel.com> <7647f032-29ee-ef83-d0a6-b625cef00b72@gmail.com> <05859c14-e4a9-db9e-bb4c-35aa26d04c23@arm.com> From: Oleksandr Andrushchenko Message-ID: <2cc94762-d027-95bb-9e0d-c72e98da082c@gmail.com> Date: Tue, 10 Apr 2018 14:04:45 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <05859c14-e4a9-db9e-bb4c-35aa26d04c23@arm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/10/2018 01:47 PM, Julien Grall wrote: > Hi, > > On 04/10/2018 09:53 AM, Oleksandr Andrushchenko wrote: >> On 02/14/2018 03:50 AM, Dongwon Kim wrote: >>> diff --git a/drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_id.h > > [...] > >>> +#ifndef __HYPER_DMABUF_ID_H__ >>> +#define __HYPER_DMABUF_ID_H__ >>> + >>> +#define HYPER_DMABUF_ID_CREATE(domid, cnt) \ >>> +    ((((domid) & 0xFF) << 24) | ((cnt) & 0xFFFFFF)) >> I would define hyper_dmabuf_id_t.id as a union or 2 separate >> fields to avoid his magic > > I am not sure the union would be right here because the layout will > differs between big and little endian. Agree > So does that value will be passed to other guest? As per my understanding yes, with HYPER_DMABUF_EXPORT request > > Cheers, >