From patchwork Mon May 17 09:55:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yongji Xie X-Patchwork-Id: 12261393 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=-16.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 2AA61C43460 for ; Mon, 17 May 2021 09:55:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F356D610FC for ; Mon, 17 May 2021 09:55:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229474AbhEQJ5N (ORCPT ); Mon, 17 May 2021 05:57:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35118 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230248AbhEQJ5M (ORCPT ); Mon, 17 May 2021 05:57:12 -0400 Received: from mail-pj1-x102d.google.com (mail-pj1-x102d.google.com [IPv6:2607:f8b0:4864:20::102d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E5F85C061573 for ; Mon, 17 May 2021 02:55:56 -0700 (PDT) Received: by mail-pj1-x102d.google.com with SMTP id q6so3376564pjj.2 for ; Mon, 17 May 2021 02:55:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=MouAXVU0J/gA4I5GTy8SeyqWRECXQkyC0TfR7o+Hz5c=; b=X0NTR58R14qMnCCKXWSzamLPSdg5ExgcnZ0DImKaOvMCmLt88fIAkwnd6J2goufzIn LZOX15kilgG1Dpn4/vP2PG+4Fhi9vZbkrEJqmJZewuKtHtv9oigd8ov8uQnpZhAzXzzZ HznvMz8uE0gElfCIgP2ZD95kpy/KRxDkVIqHHTv9FWNUnsQIHKAIXZ4iZfJ5B87lJ3EE ls2Ts5Iq15VVio05oK4AXMznPbS+avf5o5+LNh2/OC2v2z84gqMWLsSyQHn35jYspPDH Snhgb9KU1Bbc4vtTjC0l7f8i4UFqNtKCOGkMtTUJP80evpQj9KsuMqb0xS+rNEXU/L94 UBtg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=MouAXVU0J/gA4I5GTy8SeyqWRECXQkyC0TfR7o+Hz5c=; b=YEQ7J9/QpOq8BQP0pl4xv8kcLa3cQ5fu6F/JHiVHyMt33v66LLB4kjqI5ORWmeXd+M RNqHqWvCObPD2g/LNsvzlgyNO1VXDwNhC6kNZPA9sxz76qPg43kf5P/Q3UxcW0QkKOcV 4opXJwUARGAPs+DnFC6XonbzGZyc54UIHop/qeYaWryw65hE2uplso2K9SWZQWwhwfxA gfWkMCj1nIDeZ0TE+RcXDhFPn3LIvEVxFo3K2f6md5hEcYTuf9MC9dOBSWsgNrO4V0ht WpvFKqorrzxXdaaJi1PNUm3AhKIKUZLuWKdRk4Hrm9niod+db43tkNJhQkXczbfefSWG UJyA== X-Gm-Message-State: AOAM53193sGTzgMMSgPDPwbSkbeaYW+tPtR0OHZHgx9n/vafLC26kkwd U2a4MKpEjQw6giJh72eLpU8G X-Google-Smtp-Source: ABdhPJy1ehb6Kie4m4QxEvvF1uyhuUm0zgw7klsdTztxYar5dk7+iQLkZ++eK/Arz2ab9Zz4tUZOzQ== X-Received: by 2002:a17:90a:bc0c:: with SMTP id w12mr26427487pjr.213.1621245356449; Mon, 17 May 2021 02:55:56 -0700 (PDT) Received: from localhost ([139.177.225.253]) by smtp.gmail.com with ESMTPSA id h19sm10062442pgm.40.2021.05.17.02.55.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 May 2021 02:55:56 -0700 (PDT) From: Xie Yongji To: mst@redhat.com, jasowang@redhat.com, stefanha@redhat.com, sgarzare@redhat.com, parav@nvidia.com, hch@infradead.org, christian.brauner@canonical.com, rdunlap@infradead.org, willy@infradead.org, viro@zeniv.linux.org.uk, axboe@kernel.dk, bcrl@kvack.org, corbet@lwn.net, mika.penttila@nextfour.com, dan.carpenter@oracle.com, joro@8bytes.org Cc: virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, kvm@vger.kernel.org, linux-fsdevel@vger.kernel.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org Subject: [PATCH v7 00/12] Introduce VDUSE - vDPA Device in Userspace Date: Mon, 17 May 2021 17:55:01 +0800 Message-Id: <20210517095513.850-1-xieyongji@bytedance.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This series introduces a framework, which can be used to implement vDPA Devices in a userspace program. The work consist of two parts: control path forwarding and data path offloading. In the control path, the VDUSE driver will make use of message mechnism to forward the config operation from vdpa bus driver to userspace. Userspace can use read()/write() to receive/reply those control messages. In the data path, the core is mapping dma buffer into VDUSE daemon's address space, which can be implemented in different ways depending on the vdpa bus to which the vDPA device is attached. In virtio-vdpa case, we implements a MMU-based on-chip IOMMU driver with bounce-buffering mechanism to achieve that. And in vhost-vdpa case, the dma buffer is reside in a userspace memory region which can be shared to the VDUSE userspace processs via transferring the shmfd. The details and our user case is shown below: ------------------------ ------------------------- ---------------------------------------------- | Container | | QEMU(VM) | | VDUSE daemon | | --------- | | ------------------- | | ------------------------- ---------------- | | |dev/vdx| | | |/dev/vhost-vdpa-x| | | | vDPA device emulation | | block driver | | ------------+----------- -----------+------------ -------------+----------------------+--------- | | | | | | | | ------------+---------------------------+----------------------------+----------------------+--------- | | block device | | vhost device | | vduse driver | | TCP/IP | | | -------+-------- --------+-------- -------+-------- -----+---- | | | | | | | | ----------+---------- ----------+----------- -------+------- | | | | virtio-blk driver | | vhost-vdpa driver | | vdpa device | | | | ----------+---------- ----------+----------- -------+------- | | | | virtio bus | | | | | --------+----+----------- | | | | | | | | | | | ----------+---------- | | | | | | virtio-blk device | | | | | | ----------+---------- | | | | | | | | | | | -----------+----------- | | | | | | virtio-vdpa driver | | | | | | -----------+----------- | | | | | | | | vdpa bus | | | -----------+----------------------+---------------------------+------------ | | | ---+--- | -----------------------------------------------------------------------------------------| NIC |------ ---+--- | ---------+--------- | Remote Storages | ------------------- We make use of it to implement a block device connecting to our distributed storage, which can be used both in containers and VMs. Thus, we can have an unified technology stack in this two cases. To test it with null-blk: $ qemu-storage-daemon \ --chardev socket,id=charmonitor,path=/tmp/qmp.sock,server,nowait \ --monitor chardev=charmonitor \ --blockdev driver=host_device,cache.direct=on,aio=native,filename=/dev/nullb0,node-name=disk0 \ --export type=vduse-blk,id=test,node-name=disk0,writable=on,name=vduse-null,num-queues=16,queue-size=128 The qemu-storage-daemon can be found at https://github.com/bytedance/qemu/tree/vduse To make the userspace VDUSE processes such as qemu-storage-daemon able to run unprivileged. We did some works on virtio driver to avoid trusting device, including: - validating the device status: * https://lore.kernel.org/lkml/20210517093428.670-1-xieyongji@bytedance.com/ - validating the used length: * https://lore.kernel.org/lkml/20210517090836.533-1-xieyongji@bytedance.com/ - validating the device config: * patch 4 ("virtio-blk: Add validation for block size in config space") - validating the device response: * patch 5 ("virtio_scsi: Add validation for residual bytes from response") Since I'm not sure if I missing something during auditing, especially on some virtio device drivers that I'm not familiar with, now we only support emualting a few vDPA devices by default, including: virtio-net device, virtio-blk device, virtio-scsi device and virtio-fs device. This limitaion can help to reduce security risks. When a sysadmin trusts the userspace process enough, it can relax the limitation with a 'allow_unsafe_device_emulation' module parameter. Future work: - Improve performance - Userspace library (find a way to reuse device emulation code in qemu/rust-vmm) V6 to V7: - Export alloc_iova_fast() - Add get_config_size() callback - Add some patches to avoid trusting virtio devices - Add limited device emulation - Add some documents - Use workqueue to inject config irq - Add parameter on vq irq injecting - Rename vduse_domain_get_mapping_page() to vduse_domain_get_coherent_page() - Add WARN_ON() to catch message failure - Add some padding/reserved fields to uAPI structure - Fix some bugs - Rebase to vhost.git V5 to V6: - Export receive_fd() instead of __receive_fd() - Factor out the unmapping logic of pa and va separatedly - Remove the logic of bounce page allocation in page fault handler - Use PAGE_SIZE as IOVA allocation granule - Add EPOLLOUT support - Enable setting API version in userspace - Fix some bugs V4 to V5: - Remove the patch for irq binding - Use a single IOTLB for all types of mapping - Factor out vhost_vdpa_pa_map() - Add some sample codes in document - Use receice_fd_user() to pass file descriptor - Fix some bugs V3 to V4: - Rebase to vhost.git - Split some patches - Add some documents - Use ioctl to inject interrupt rather than eventfd - Enable config interrupt support - Support binding irq to the specified cpu - Add two module parameter to limit bounce/iova size - Create char device rather than anon inode per vduse - Reuse vhost IOTLB for iova domain - Rework the message mechnism in control path V2 to V3: - Rework the MMU-based IOMMU driver - Use the iova domain as iova allocator instead of genpool - Support transferring vma->vm_file in vhost-vdpa - Add SVA support in vhost-vdpa - Remove the patches on bounce pages reclaim V1 to V2: - Add vhost-vdpa support - Add some documents - Based on the vdpa management tool - Introduce a workqueue for irq injection - Replace interval tree with array map to store the iova_map Xie Yongji (12): iova: Export alloc_iova_fast() file: Export receive_fd() to modules eventfd: Increase the recursion depth of eventfd_signal() virtio-blk: Add validation for block size in config space virtio_scsi: Add validation for residual bytes from response vhost-iotlb: Add an opaque pointer for vhost IOTLB vdpa: Add an opaque pointer for vdpa_config_ops.dma_map() vdpa: factor out vhost_vdpa_pa_map() and vhost_vdpa_pa_unmap() vdpa: Support transferring virtual addressing during DMA mapping vduse: Implement an MMU-based IOMMU driver vduse: Introduce VDUSE - vDPA Device in Userspace Documentation: Add documentation for VDUSE Documentation/userspace-api/index.rst | 1 + Documentation/userspace-api/ioctl/ioctl-number.rst | 1 + Documentation/userspace-api/vduse.rst | 243 ++++ drivers/block/virtio_blk.c | 2 +- drivers/iommu/iova.c | 1 + drivers/scsi/virtio_scsi.c | 2 +- drivers/vdpa/Kconfig | 10 + drivers/vdpa/Makefile | 1 + drivers/vdpa/ifcvf/ifcvf_main.c | 2 +- drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 +- drivers/vdpa/vdpa.c | 9 +- drivers/vdpa/vdpa_sim/vdpa_sim.c | 8 +- drivers/vdpa/vdpa_user/Makefile | 5 + drivers/vdpa/vdpa_user/iova_domain.c | 531 +++++++ drivers/vdpa/vdpa_user/iova_domain.h | 70 + drivers/vdpa/vdpa_user/vduse_dev.c | 1453 ++++++++++++++++++++ drivers/vdpa/virtio_pci/vp_vdpa.c | 2 +- drivers/vhost/iotlb.c | 20 +- drivers/vhost/vdpa.c | 148 +- fs/eventfd.c | 2 +- fs/file.c | 6 + include/linux/eventfd.h | 5 +- include/linux/file.h | 7 +- include/linux/vdpa.h | 21 +- include/linux/vhost_iotlb.h | 3 + include/uapi/linux/vduse.h | 178 +++ 26 files changed, 2681 insertions(+), 52 deletions(-) create mode 100644 Documentation/userspace-api/vduse.rst create mode 100644 drivers/vdpa/vdpa_user/Makefile create mode 100644 drivers/vdpa/vdpa_user/iova_domain.c create mode 100644 drivers/vdpa/vdpa_user/iova_domain.h create mode 100644 drivers/vdpa/vdpa_user/vduse_dev.c create mode 100644 include/uapi/linux/vduse.h