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 C429FC433FE for ; Fri, 4 Mar 2022 10:26:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234249AbiCDK07 (ORCPT ); Fri, 4 Mar 2022 05:26:59 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39730 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234093AbiCDK04 (ORCPT ); Fri, 4 Mar 2022 05:26:56 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 168EC1AA057 for ; Fri, 4 Mar 2022 02:26:09 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646389568; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=dg2DjhTzspXnkPdxQ4L1gE7F4LBl/cnUsJCfA7PY7HU=; b=GjoSA7vwD353jDcuo6/J4baUOGUFsWiJWlU5O4uhbcYZ9gygiUsD89AdCJVuORN35h31FH oEHsDAc3vdwRDhwYfx9QJwzbKacsPPOtejKQmI+9KO5Kj26HWG39VglhsEqmyV3CsGVLvQ fyF7+Yi8O1BUMOprDPF22CleNT+AB2A= Received: from mail-qk1-f199.google.com (mail-qk1-f199.google.com [209.85.222.199]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-222-IaUsO2SDMZi6fXPWBwozhA-1; Fri, 04 Mar 2022 05:26:05 -0500 X-MC-Unique: IaUsO2SDMZi6fXPWBwozhA-1 Received: by mail-qk1-f199.google.com with SMTP id a15-20020a05620a066f00b0060c66d84489so5182220qkh.19 for ; Fri, 04 Mar 2022 02:26:05 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=dg2DjhTzspXnkPdxQ4L1gE7F4LBl/cnUsJCfA7PY7HU=; b=TXNygLgpm95KenpF6bzSKqE91dwxVWKU+jOLnmmFx2yHCwICQK/fdGxPsl8YdxBJKC 5CTyE9KZzSSrYdwpjxgrasLGrKdNi6Ny7u0c5NhymVRkGDJuPsSTSzQ73oqM4+yZ+CIl Ywu10V6LO8rf+yF9SwyTvdMmuwbbO4+yUf1CazzD0Ihf/2hMFEfTe7uw9kaAdJbvJ3Aj k1UvV271+JMdokhGSbD/6IYB3IqtPlhMxXD5lUF0kQ+DSCYSOXRK2s4CEctkQAOGzqZ5 thq/3kKNpIPIpBPTiTyL66DS8hzA00GrbUG3dadDAjE/UKRtqxX9bbny+h+b1UxS9Bm+ qtEA== X-Gm-Message-State: AOAM533JTzPx+FDMSytVnxWKgIUmDM7nQXGT7QQEvhrGbo9B5BMYB1XS QRhcTppJWq2PrZagDEwSiw9R3szevwHIK/BoYIOrcEzS1n9BF4VPHPgju3xIV4RWY8uQg4uwbf3 J8RSh2cAKmqcWJtyTgYODYOz4EOdu9Utn5Nv74a9u X-Received: by 2002:a05:620a:22a6:b0:662:e97d:c7bc with SMTP id p6-20020a05620a22a600b00662e97dc7bcmr2045273qkh.486.1646389564504; Fri, 04 Mar 2022 02:26:04 -0800 (PST) X-Google-Smtp-Source: ABdhPJx1kvpYAW//FncPCrmWqRNA2ZHLRo4go2ItEjZkcWjMdDDeSf32X9DZm+GH63oF+p5dNcZRS3Kz9G/HtkiuCqU= X-Received: by 2002:a05:620a:22a6:b0:662:e97d:c7bc with SMTP id p6-20020a05620a22a600b00662e97dc7bcmr2045261qkh.486.1646389564236; Fri, 04 Mar 2022 02:26:04 -0800 (PST) MIME-Version: 1.0 References: <20201216064818.48239-1-jasowang@redhat.com> <20220224212314.1326-1-gdawar@xilinx.com> <20220224212314.1326-10-gdawar@xilinx.com> In-Reply-To: <20220224212314.1326-10-gdawar@xilinx.com> From: Eugenio Perez Martin Date: Fri, 4 Mar 2022 11:25:28 +0100 Message-ID: Subject: Re: [RFC PATCH v2 09/19] vhost: support ASID in IOTLB API To: Gautam Dawar Cc: Gautam Dawar , Martin Petrus Hubertus Habets , Harpreet Singh Anand , tanujk@xilinx.com, Jason Wang , "Michael S. Tsirkin" , Zhu Lingshan , Stefano Garzarella , Xie Yongji , Eli Cohen , Si-Wei Liu , Parav Pandit , Longpeng , virtualization , linux-kernel@vger.kernel.org, kvm list , netdev@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 24, 2022 at 10:26 PM Gautam Dawar wrote: > > This patches allows userspace to send ASID based IOTLB message to > vhost. This idea is to use the reserved u32 field in the existing V2 > IOTLB message. Vhost device should advertise this capability via > VHOST_BACKEND_F_IOTLB_ASID backend feature. > > Signed-off-by: Jason Wang > Signed-off-by: Gautam Dawar > --- > drivers/vhost/vdpa.c | 5 ++++- > drivers/vhost/vhost.c | 23 ++++++++++++++++++----- > drivers/vhost/vhost.h | 4 ++-- > include/uapi/linux/vhost_types.h | 6 +++++- > 4 files changed, 29 insertions(+), 9 deletions(-) > > diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c > index 6bf755f84d26..d0aacc0cc79a 100644 > --- a/drivers/vhost/vdpa.c > +++ b/drivers/vhost/vdpa.c > @@ -836,7 +836,7 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v, > msg->perm); > } > > -static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev, > +static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev, u32 asid, > struct vhost_iotlb_msg *msg) > { > struct vhost_vdpa *v = container_of(dev, struct vhost_vdpa, vdev); > @@ -847,6 +847,9 @@ static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev, > > mutex_lock(&dev->mutex); > > + if (asid != 0) > + return -EINVAL; > + Should we check for asid != 0 before acquiring the mutex? Otherwise the code never releases it. > r = vhost_dev_check_owner(dev); > if (r) > goto unlock; > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > index 59edb5a1ffe2..1f514d98f0de 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -468,7 +468,7 @@ void vhost_dev_init(struct vhost_dev *dev, > struct vhost_virtqueue **vqs, int nvqs, > int iov_limit, int weight, int byte_weight, > bool use_worker, > - int (*msg_handler)(struct vhost_dev *dev, > + int (*msg_handler)(struct vhost_dev *dev, u32 asid, > struct vhost_iotlb_msg *msg)) > { > struct vhost_virtqueue *vq; > @@ -1090,11 +1090,14 @@ static bool umem_access_ok(u64 uaddr, u64 size, int access) > return true; > } > > -static int vhost_process_iotlb_msg(struct vhost_dev *dev, > +static int vhost_process_iotlb_msg(struct vhost_dev *dev, u32 asid, > struct vhost_iotlb_msg *msg) > { > int ret = 0; > > + if (asid != 0) > + return -EINVAL; > + > mutex_lock(&dev->mutex); > vhost_dev_lock_vqs(dev); > switch (msg->type) { > @@ -1141,6 +1144,7 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev, > struct vhost_iotlb_msg msg; > size_t offset; > int type, ret; > + u32 asid = 0; > > ret = copy_from_iter(&type, sizeof(type), from); > if (ret != sizeof(type)) { > @@ -1156,7 +1160,16 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev, > offset = offsetof(struct vhost_msg, iotlb) - sizeof(int); > break; > case VHOST_IOTLB_MSG_V2: > - offset = sizeof(__u32); > + if (vhost_backend_has_feature(dev->vqs[0], > + VHOST_BACKEND_F_IOTLB_ASID)) { > + ret = copy_from_iter(&asid, sizeof(asid), from); > + if (ret != sizeof(asid)) { > + ret = -EINVAL; > + goto done; > + } > + offset = sizeof(__u16); > + } else > + offset = sizeof(__u32); > break; > default: > ret = -EINVAL; > @@ -1171,9 +1184,9 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev, > } > > if (dev->msg_handler) > - ret = dev->msg_handler(dev, &msg); > + ret = dev->msg_handler(dev, asid, &msg); > else > - ret = vhost_process_iotlb_msg(dev, &msg); > + ret = vhost_process_iotlb_msg(dev, asid, &msg); > if (ret) { > ret = -EFAULT; > goto done; > diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h > index 638bb640d6b4..9f238d6c7b58 100644 > --- a/drivers/vhost/vhost.h > +++ b/drivers/vhost/vhost.h > @@ -161,7 +161,7 @@ struct vhost_dev { > int byte_weight; > u64 kcov_handle; > bool use_worker; > - int (*msg_handler)(struct vhost_dev *dev, > + int (*msg_handler)(struct vhost_dev *dev, u32 asid, > struct vhost_iotlb_msg *msg); > }; > > @@ -169,7 +169,7 @@ bool vhost_exceeds_weight(struct vhost_virtqueue *vq, int pkts, int total_len); > void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs, > int nvqs, int iov_limit, int weight, int byte_weight, > bool use_worker, > - int (*msg_handler)(struct vhost_dev *dev, > + int (*msg_handler)(struct vhost_dev *dev, u32 asid, > struct vhost_iotlb_msg *msg)); > long vhost_dev_set_owner(struct vhost_dev *dev); > bool vhost_dev_has_owner(struct vhost_dev *dev); > diff --git a/include/uapi/linux/vhost_types.h b/include/uapi/linux/vhost_types.h > index 76ee7016c501..634cee485abb 100644 > --- a/include/uapi/linux/vhost_types.h > +++ b/include/uapi/linux/vhost_types.h > @@ -87,7 +87,7 @@ struct vhost_msg { > > struct vhost_msg_v2 { > __u32 type; > - __u32 reserved; > + __u32 asid; > union { > struct vhost_iotlb_msg iotlb; > __u8 padding[64]; > @@ -157,5 +157,9 @@ struct vhost_vdpa_iova_range { > #define VHOST_BACKEND_F_IOTLB_MSG_V2 0x1 > /* IOTLB can accept batching hints */ > #define VHOST_BACKEND_F_IOTLB_BATCH 0x2 > +/* IOTLB can accept address space identifier through V2 type of IOTLB > + * message > + */ > +#define VHOST_BACKEND_F_IOTLB_ASID 0x3 > > #endif > -- > 2.25.0 >