From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4EBE3C10F05 for ; Wed, 20 Mar 2019 10:45:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 241A92184E for ; Wed, 20 Mar 2019 10:45:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727769AbfCTKph (ORCPT ); Wed, 20 Mar 2019 06:45:37 -0400 Received: from lb2-smtp-cloud8.xs4all.net ([194.109.24.25]:34017 "EHLO lb2-smtp-cloud8.xs4all.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725905AbfCTKph (ORCPT ); Wed, 20 Mar 2019 06:45:37 -0400 Received: from [IPv6:2001:983:e9a7:1:f1c5:c100:28a:d83e] ([IPv6:2001:983:e9a7:1:f1c5:c100:28a:d83e]) by smtp-cloud8.xs4all.net with ESMTPA id 6YizhA4Im4HFn6Yj0hy27k; Wed, 20 Mar 2019 11:45:34 +0100 Subject: Re: [PATCH v5 01/23] vb2: add requires_requests bit for stateless codecs To: Mauro Carvalho Chehab , Dafna Hirschfeld Cc: linux-media@vger.kernel.org, helen.koike@collabora.com, Hans Verkuil References: <20190306211343.15302-1-dafna3@gmail.com> <20190306211343.15302-2-dafna3@gmail.com> <20190320072124.675fd13b@coco.lan> From: Hans Verkuil Message-ID: Date: Wed, 20 Mar 2019 11:45:33 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.1 MIME-Version: 1.0 In-Reply-To: <20190320072124.675fd13b@coco.lan> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-CMAE-Envelope: MS4wfEDJhI+mh+VHBJvVfYzj3gilyuXTwRM+KXrPduecBMKxausAzLrjKvTgnGVKp+bjrT4RZotA5CKTu47quzDh9yNoV1d243qlqz5lVJ4yd3xyBEnTrYQP r0hT2hDjJ/SfedgRsZaGo9hxzezbQLNafNLaXKesPgB+8v/7ejm/D0TNAYFWHdiJzKoi8qotL+ThgRtBjnA4CEMST0qfEvJ0A6t1UmRxocenS9zFTriFEJFp bb8f3zB//XzoISGsa/K7GV4KnlQP4CoSrkS6oWXeV3YF56h36B+Wv4IVHuODL1eMWpE1ShjI5Y9dD4+lt5BYmpvthzbsBCFvz8NTkW6DXAH5dUMNJWj8tagG AGFTyIZ0PvWdNWZYU0ql4q/jncUuQL024NjneCGApP61rAo/ifibxa91Do8lS+Ajc8lXmX4t Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org On 3/20/19 11:21 AM, Mauro Carvalho Chehab wrote: > Em Wed, 6 Mar 2019 13:13:21 -0800 > Dafna Hirschfeld escreveu: > >> From: Hans Verkuil >> >> Stateless codecs require the use of the Request API as opposed of it >> being optional. >> >> So add a bit to indicate this and let vb2 check for this. >> >> Signed-off-by: Hans Verkuil >> --- >> drivers/media/common/videobuf2/videobuf2-core.c | 5 ++++- >> drivers/media/common/videobuf2/videobuf2-v4l2.c | 6 ++++++ >> include/media/videobuf2-core.h | 3 +++ >> 3 files changed, 13 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c >> index 15b6b9c0a2e4..d8cf9d3ec54d 100644 >> --- a/drivers/media/common/videobuf2/videobuf2-core.c >> +++ b/drivers/media/common/videobuf2/videobuf2-core.c >> @@ -1518,7 +1518,7 @@ int vb2_core_qbuf(struct vb2_queue *q, unsigned int index, void *pb, >> >> if ((req && q->uses_qbuf) || >> (!req && vb->state != VB2_BUF_STATE_IN_REQUEST && >> - q->uses_requests)) { >> + (q->uses_requests || q->requires_requests))) { >> dprintk(1, "queue in wrong mode (qbuf vs requests)\n"); >> return -EBUSY; > > Huh? -EBUSY doesn't seem the right error code to be issued if a driver > ignores V4L2_BUF_CAP_REQUIRES_REQUESTS. I agree. See my next comment below. > >> } >> @@ -2247,6 +2247,9 @@ int vb2_core_queue_init(struct vb2_queue *q) >> WARN_ON(!q->ops->buf_queue)) >> return -EINVAL; >> >> + if (WARN_ON(q->requires_requests && !q->supports_requests)) >> + return -EINVAL; >> + >> INIT_LIST_HEAD(&q->queued_list); >> INIT_LIST_HEAD(&q->done_list); >> spin_lock_init(&q->done_lock); >> diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c >> index d09dee20e421..4dc4855056f1 100644 >> --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c >> +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c >> @@ -385,6 +385,10 @@ static int vb2_queue_or_prepare_buf(struct vb2_queue *q, struct media_device *md >> dprintk(1, "%s: queue uses requests\n", opname); >> return -EBUSY; >> } >> + if (q->requires_requests) { >> + dprintk(1, "%s: queue requires requests\n", opname); >> + return -EACCES; > > I also don't think that -EACCES is the right error. This is not a matter of > wrong permissions. Running the app as root won't make it work. I believe EPERM is returned if you have the wrong permissions. EACCES is returned when you are in the wrong mode, e.g. when attempting to set a read-only control, or read from a write-only control. So I believe this is indeed the right error code. And I also agree that the core code above should return EACCES as well in this particular case instead of EBUSY. Regards, Hans > >> + } >> return 0; >> } else if (!q->supports_requests) { >> dprintk(1, "%s: queue does not support requests\n", opname); >> @@ -658,6 +662,8 @@ static void fill_buf_caps(struct vb2_queue *q, u32 *caps) >> #ifdef CONFIG_MEDIA_CONTROLLER_REQUEST_API >> if (q->supports_requests) >> *caps |= V4L2_BUF_CAP_SUPPORTS_REQUESTS; >> + if (q->requires_requests) >> + *caps |= V4L2_BUF_CAP_REQUIRES_REQUESTS; >> #endif >> } >> >> diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h >> index 910f3d469005..fbf8dbbcbc09 100644 >> --- a/include/media/videobuf2-core.h >> +++ b/include/media/videobuf2-core.h >> @@ -484,6 +484,8 @@ struct vb2_buf_ops { >> * has not been called. This is a vb1 idiom that has been adopted >> * also by vb2. >> * @supports_requests: this queue supports the Request API. >> + * @requires_requests: this queue requires the Request API. If this is set to 1, >> + * then supports_requests must be set to 1 as well. >> * @uses_qbuf: qbuf was used directly for this queue. Set to 1 the first >> * time this is called. Set to 0 when the queue is canceled. >> * If this is 1, then you cannot queue buffers from a request. >> @@ -558,6 +560,7 @@ struct vb2_queue { >> unsigned allow_zero_bytesused:1; >> unsigned quirk_poll_must_check_waiting_for_buffers:1; >> unsigned supports_requests:1; >> + unsigned requires_requests:1; >> unsigned uses_qbuf:1; >> unsigned uses_requests:1; >> > > > > Thanks, > Mauro >