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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 74BB0C433EF for ; Fri, 1 Jul 2022 06:43:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233418AbiGAGnk (ORCPT ); Fri, 1 Jul 2022 02:43:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44322 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229481AbiGAGnj (ORCPT ); Fri, 1 Jul 2022 02:43:39 -0400 Received: from out30-130.freemail.mail.aliyun.com (out30-130.freemail.mail.aliyun.com [115.124.30.130]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 88AB931913; Thu, 30 Jun 2022 23:43:36 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R801e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046049;MF=xuanzhuo@linux.alibaba.com;NM=1;PH=DS;RN=36;SR=0;TI=SMTPD_---0VHzJr.6_1656657809; Received: from localhost(mailfrom:xuanzhuo@linux.alibaba.com fp:SMTPD_---0VHzJr.6_1656657809) by smtp.aliyun-inc.com; Fri, 01 Jul 2022 14:43:30 +0800 Message-ID: <1656657725.7418885-1-xuanzhuo@linux.alibaba.com> Subject: Re: [PATCH v11 02/40] virtio: struct virtio_config_ops add callbacks for queue_reset Date: Fri, 1 Jul 2022 14:42:05 +0800 From: Xuan Zhuo To: "Michael S. Tsirkin" Cc: virtualization@lists.linux-foundation.org, Richard Weinberger , Anton Ivanov , Johannes Berg , Jason Wang , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Hans de Goede , Mark Gross , Vadim Pasternak , Bjorn Andersson , Mathieu Poirier , Cornelia Huck , Halil Pasic , Eric Farman , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Vincent Whitchurch , linux-um@lists.infradead.org, netdev@vger.kernel.org, platform-driver-x86@vger.kernel.org, linux-remoteproc@vger.kernel.org, linux-s390@vger.kernel.org, kvm@vger.kernel.org, bpf@vger.kernel.org, kangjie.xu@linux.alibaba.com References: <20220629065656.54420-1-xuanzhuo@linux.alibaba.com> <20220629065656.54420-3-xuanzhuo@linux.alibaba.com> <20220701022728-mutt-send-email-mst@kernel.org> In-Reply-To: <20220701022728-mutt-send-email-mst@kernel.org> Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Fri, 1 Jul 2022 02:28:46 -0400, "Michael S. Tsirkin" wrote: > On Wed, Jun 29, 2022 at 02:56:18PM +0800, Xuan Zhuo wrote: > > reset can be divided into the following four steps (example): > > 1. transport: notify the device to reset the queue > > 2. vring: recycle the buffer submitted > > 3. vring: reset/resize the vring (may re-alloc) > > 4. transport: mmap vring to device, and enable the queue > > > > In order to support queue reset, add two callbacks(reset_vq, > > enable_reset_vq) in struct virtio_config_ops to implement steps 1 and 4. > > > > Signed-off-by: Xuan Zhuo > > --- > > include/linux/virtio_config.h | 12 ++++++++++++ > > 1 file changed, 12 insertions(+) > > > > diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h > > index b47c2e7ed0ee..ded51b0d4823 100644 > > --- a/include/linux/virtio_config.h > > +++ b/include/linux/virtio_config.h > > @@ -78,6 +78,16 @@ struct virtio_shm_region { > > * @set_vq_affinity: set the affinity for a virtqueue (optional). > > * @get_vq_affinity: get the affinity for a virtqueue (optional). > > * @get_shm_region: get a shared memory region based on the index. > > + * @reset_vq: reset a queue individually (optional). > > + * vq: the virtqueue > > + * Returns 0 on success or error status > > + * reset_vq will guarantee that the callbacks are disabled and synchronized. > > + * Except for the callback, the caller should guarantee that the vring is > > + * not accessed by any functions of virtqueue. > > + * @enable_reset_vq: enable a reset queue > > + * vq: the virtqueue > > + * Returns 0 on success or error status > > + * If reset_vq is set, then enable_reset_vq must also be set. > > */ > > typedef void vq_callback_t(struct virtqueue *); > > struct virtio_config_ops { > > @@ -104,6 +114,8 @@ struct virtio_config_ops { > > int index); > > bool (*get_shm_region)(struct virtio_device *vdev, > > struct virtio_shm_region *region, u8 id); > > + int (*reset_vq)(struct virtqueue *vq); > > + int (*enable_reset_vq)(struct virtqueue *vq); > > }; > > The names need some tweaking. > I came up with > int (*disable_vq_and_reset)(struct virtqueue *vq); > int (*enable_vq_after_reset)(struct virtqueue *vq); OK, I will use these two names in the next version. Hope Jason likes it too. Thanks. > > > > /* If driver didn't advertise the feature, it will never appear. */ > > -- > > 2.31.0 >