From patchwork Tue May 26 10:58:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Stevens X-Patchwork-Id: 11572133 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4014E1392 for ; Wed, 27 May 2020 07:16:15 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1F69C20C56 for ; Wed, 27 May 2020 07:16:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="FwnjV3qx" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1F69C20C56 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 76EE56E2A3; Wed, 27 May 2020 07:16:14 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail-pg1-x542.google.com (mail-pg1-x542.google.com [IPv6:2607:f8b0:4864:20::542]) by gabe.freedesktop.org (Postfix) with ESMTPS id CAA9489D2F for ; Tue, 26 May 2020 10:59:31 +0000 (UTC) Received: by mail-pg1-x542.google.com with SMTP id m1so3681549pgk.1 for ; Tue, 26 May 2020 03:59:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=iAlP2BKBM2IVeAB4qz6cPqLCcfc3BaLSNbTl+NqVHeA=; b=FwnjV3qxAQJDFSBaCKgKOauyWGb9BLnlCccQ8tHbNsgb3J6GaeLQfssFiYN+verRCm NXVB2bgkz89CODukw+QFJv3fxo4JXPbVRJxYxa7Sy2ttfOOmnSuDxVpsGLJm3gXMlM6m eL/g9U43MLD1YrE/PXUmXaHOJtHP+bMRtLXTc= 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=iAlP2BKBM2IVeAB4qz6cPqLCcfc3BaLSNbTl+NqVHeA=; b=fQjIIMYsLmD5iAbtUyElbmnddIr+znmxWqaRwEeNuMh5sCA6cjiQINIzKQC3K+72a2 CahzifHRHFRzv/KWBgaGKG2qQmA4ymlpPhOuuz0omnaXchzK9hAxlUqLbatKHf7H26Ij tXTMbWREM7e/DdYMZV/qzYeXml3+IV8Uj34WWb/+r20kIT79t5x2PLV++mMvHhRn3O0g pw3TEpGUkId3vXsQmlwm82o7iO589v4cYNFRPTfhHbdYse0o/t2jOrYFJjfVrA2Iv4fq Sy2DggtjfN/FF8lWLJldZh5cR0E+S5sJgbKf3Ehav2phRpoV0MGRDA0QgzY9HyIQihkl tjZA== X-Gm-Message-State: AOAM532ooX0hjISJjfBaeEHe+6B0oykStZefsU3xW5a/ETtnAHMZkEvp ZY3QIB8FBbYNH+SpZQlzE03iVg== X-Google-Smtp-Source: ABdhPJyJ8CZrFBIlok90zHxbI0YlMit5hBKFtKth00t5BVi8PMAVMIMXqo1kGxqZEO/9QkQ4wJn8Qw== X-Received: by 2002:a65:67d3:: with SMTP id b19mr485969pgs.431.1590490771266; Tue, 26 May 2020 03:59:31 -0700 (PDT) Received: from localhost ([2401:fa00:8f:203:30f2:7a9c:387e:6c7]) by smtp.gmail.com with ESMTPSA id a16sm14773438pjs.23.2020.05.26.03.59.27 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 26 May 2020 03:59:30 -0700 (PDT) From: David Stevens To: Gerd Hoffmann , David Airlie , Daniel Vetter , Sumit Semwal Subject: [PATCH v4 1/3] virtio: add dma-buf support for exported objects Date: Tue, 26 May 2020 19:58:09 +0900 Message-Id: <20200526105811.30784-2-stevensd@chromium.org> X-Mailer: git-send-email 2.27.0.rc0.183.gde8f92d652-goog In-Reply-To: <20200526105811.30784-1-stevensd@chromium.org> References: <20200526105811.30784-1-stevensd@chromium.org> MIME-Version: 1.0 X-Mailman-Approved-At: Wed, 27 May 2020 07:15:42 +0000 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: virtio-dev@lists.oasis-open.org, dri-devel@lists.freedesktop.org, "Michael S . Tsirkin" , Jason Wang , linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, linaro-mm-sig@lists.linaro.org, David Stevens , Thomas Zimmermann , linux-media@vger.kernel.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" This change adds a new flavor of dma-bufs that can be used by virtio drivers to share exported objects. A virtio dma-buf can be queried by virtio drivers to obtain the UUID which identifies the underlying exported object. Signed-off-by: David Stevens --- drivers/virtio/Makefile | 2 +- drivers/virtio/virtio.c | 6 +++ drivers/virtio/virtio_dma_buf.c | 89 +++++++++++++++++++++++++++++++++ include/linux/virtio.h | 1 + include/linux/virtio_dma_buf.h | 58 +++++++++++++++++++++ 5 files changed, 155 insertions(+), 1 deletion(-) create mode 100644 drivers/virtio/virtio_dma_buf.c create mode 100644 include/linux/virtio_dma_buf.h diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile index 29a1386ecc03..ecdae5b596de 100644 --- a/drivers/virtio/Makefile +++ b/drivers/virtio/Makefile @@ -1,5 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 -obj-$(CONFIG_VIRTIO) += virtio.o virtio_ring.o +obj-$(CONFIG_VIRTIO) += virtio.o virtio_ring.o virtio_dma_buf.o obj-$(CONFIG_VIRTIO_MMIO) += virtio_mmio.o obj-$(CONFIG_VIRTIO_PCI) += virtio_pci.o virtio_pci-y := virtio_pci_modern.o virtio_pci_common.o diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c index a977e32a88f2..5d46f0ded92d 100644 --- a/drivers/virtio/virtio.c +++ b/drivers/virtio/virtio.c @@ -357,6 +357,12 @@ int register_virtio_device(struct virtio_device *dev) } EXPORT_SYMBOL_GPL(register_virtio_device); +bool is_virtio_device(struct device *dev) +{ + return dev->bus == &virtio_bus; +} +EXPORT_SYMBOL_GPL(is_virtio_device); + void unregister_virtio_device(struct virtio_device *dev) { int index = dev->index; /* save for after device release */ diff --git a/drivers/virtio/virtio_dma_buf.c b/drivers/virtio/virtio_dma_buf.c new file mode 100644 index 000000000000..23e3399b11ed --- /dev/null +++ b/drivers/virtio/virtio_dma_buf.c @@ -0,0 +1,89 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * dma-bufs for virtio exported objects + * + * Copyright (C) 2020 Google, Inc. + */ + +#include + +/** + * virtio_dma_buf_export - Creates a new dma-buf for a virtio exported object + * + * This wraps dma_buf_export() to allow virtio drivers to create a dma-buf + * for an virtio exported object that can be queried by other virtio drivers + * for the object's UUID. + */ +struct dma_buf *virtio_dma_buf_export( + const struct virtio_dma_buf_export_info *virtio_exp_info) +{ + struct dma_buf_export_info exp_info; + + if (!virtio_exp_info->ops + || virtio_exp_info->ops->ops.attach != &virtio_dma_buf_attach + || !virtio_exp_info->ops->get_uuid) { + return ERR_PTR(-EINVAL); + } + + exp_info.exp_name = virtio_exp_info->exp_name; + exp_info.owner = virtio_exp_info->owner; + exp_info.ops = &virtio_exp_info->ops->ops; + exp_info.size = virtio_exp_info->size; + exp_info.flags = virtio_exp_info->flags; + exp_info.resv = virtio_exp_info->resv; + exp_info.priv = virtio_exp_info->priv; + BUILD_BUG_ON(sizeof(struct virtio_dma_buf_export_info) + != sizeof(struct dma_buf_export_info)); + + return dma_buf_export(&exp_info); +} +EXPORT_SYMBOL(virtio_dma_buf_export); + +/** + * virtio_dma_buf_attach - mandatory attach callback for virtio dma-bufs + */ +int virtio_dma_buf_attach(struct dma_buf *dma_buf, + struct dma_buf_attachment *attach) +{ + int ret; + const struct virtio_dma_buf_ops *ops = container_of( + dma_buf->ops, const struct virtio_dma_buf_ops, ops); + + if (ops->device_attach) { + ret = ops->device_attach(dma_buf, attach); + if (ret) + return ret; + } + return 0; +} +EXPORT_SYMBOL(virtio_dma_buf_attach); + +/** + * is_virtio_dma_buf - returns true if the given dma-buf is a virtio dma-buf + * @dma_buf: buffer to query + */ +bool is_virtio_dma_buf(struct dma_buf *dma_buf) +{ + return dma_buf->ops->attach == &virtio_dma_buf_attach; +} +EXPORT_SYMBOL(is_virtio_dma_buf); + +/** + * virtio_dma_buf_get_uuid - gets the uuid of the virtio dma-buf's exported object + * @dma_buf: [in] buffer to query + * @uuid: [out] the uuid + * + * Returns: 0 on success, negative on failure. + */ +int virtio_dma_buf_get_uuid(struct dma_buf *dma_buf, + uuid_t *uuid) +{ + const struct virtio_dma_buf_ops *ops = container_of( + dma_buf->ops, const struct virtio_dma_buf_ops, ops); + + if (!is_virtio_dma_buf(dma_buf)) + return -EINVAL; + + return ops->get_uuid(dma_buf, uuid); +} +EXPORT_SYMBOL(virtio_dma_buf_get_uuid); diff --git a/include/linux/virtio.h b/include/linux/virtio.h index 15f906e4a748..9397e25616c4 100644 --- a/include/linux/virtio.h +++ b/include/linux/virtio.h @@ -128,6 +128,7 @@ static inline struct virtio_device *dev_to_virtio(struct device *_dev) void virtio_add_status(struct virtio_device *dev, unsigned int status); int register_virtio_device(struct virtio_device *dev); void unregister_virtio_device(struct virtio_device *dev); +bool is_virtio_device(struct device *dev); void virtio_break_device(struct virtio_device *dev); diff --git a/include/linux/virtio_dma_buf.h b/include/linux/virtio_dma_buf.h new file mode 100644 index 000000000000..29fee167afbd --- /dev/null +++ b/include/linux/virtio_dma_buf.h @@ -0,0 +1,58 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * dma-bufs for virtio exported objects + * + * Copyright (C) 2020 Google, Inc. + */ + +#ifndef _LINUX_VIRTIO_DMA_BUF_H +#define _LINUX_VIRTIO_DMA_BUF_H + +#include +#include +#include + +/** + * struct virtio_dma_buf_ops - operations possible on exported object dma-buf + * @ops: the base dma_buf_ops. ops.attach MUST be virtio_dma_buf_attach. + * @device_attach: [optional] callback invoked by virtio_dma_buf_attach during + * all attach operations. + * @get_uid: [required] callback to get the uuid of the exported object. + */ +struct virtio_dma_buf_ops { + struct dma_buf_ops ops; + int (*device_attach)(struct dma_buf *dma_buf, + struct dma_buf_attachment *attach); + int (*get_uuid)(struct dma_buf *dma_buf, uuid_t *uuid); +}; + +/** + * struct virtio_dma_buf_export_info - see struct dma_buf_export_info + */ +struct virtio_dma_buf_export_info { + const char *exp_name; + struct module *owner; + const struct virtio_dma_buf_ops *ops; + size_t size; + int flags; + struct dma_resv *resv; + void *priv; +}; + +/** + * DEFINE_VIRTIO_DMA_BUF_EXPORT_INFO - helper macro for exporters + */ +#define DEFINE_VIRTIO_DMA_BUF_EXPORT_INFO(name) \ + struct virtio_dma_buf_export_info name = { \ + .exp_name = KBUILD_MODNAME, \ + .owner = THIS_MODULE } + +int virtio_dma_buf_attach(struct dma_buf *dma_buf, + struct dma_buf_attachment *attach); + +struct dma_buf *virtio_dma_buf_export( + const struct virtio_dma_buf_export_info *virtio_exp_info); +bool is_virtio_dma_buf(struct dma_buf *dma_buf); +int virtio_dma_buf_get_uuid(struct dma_buf *dma_buf, uuid_t *uuid); + +#endif /* _LINUX_VIRTIO_DMA_BUF_H */