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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 17B1AC433E1 for ; Tue, 26 May 2020 10:59:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E327F2084C for ; Tue, 26 May 2020 10:59:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="FwnjV3qx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388811AbgEZK7d (ORCPT ); Tue, 26 May 2020 06:59:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42128 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388792AbgEZK7c (ORCPT ); Tue, 26 May 2020 06:59:32 -0400 Received: from mail-pf1-x442.google.com (mail-pf1-x442.google.com [IPv6:2607:f8b0:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D2451C08C5C1 for ; Tue, 26 May 2020 03:59:31 -0700 (PDT) Received: by mail-pf1-x442.google.com with SMTP id y18so10018018pfl.9 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=ZTbVU/n2X4aVlHVUHpPEm3SY1+esZZmltDl0GWy3uHXS1EDufLAfxOnsw69i5pyeCY 2qysKKl+wuVDQ6sc70QNx+Yn1YH7O/SmZwTm9v3FRglotFTVIVAOL1gbj+lVtax7nZUr 1og5hiMIlWQ8fA08yp+S/rLnAQDzgjbhLOnK/4I+V1OcrCFmV8DWzEmySfVessLqBfzD 5adEKkjnDORgTVmrQS/XrO96d5BVq8qYOd3KeKBbT/g4aG6pf7YCo5b33T3+2bmvllJB vAZdhuXTKFKaAB6qErUlyCsmj0Jo6iLwTm5dabbWdxPRI1YfRsP9n4zsjAdFN+cB5+sQ bfAg== X-Gm-Message-State: AOAM531exkmA1hU4lGKiJp8l0O0S1aoyFpqgBiaiiyDtrtEjCUjXTPaI oonzXUb/eIZ7Z5+0yuv7DXyl4w== 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 Cc: "Michael S . Tsirkin" , Jason Wang , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Stevens , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, virtualization@lists.linux-foundation.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org, virtio-dev@lists.oasis-open.org 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 Content-Transfer-Encoding: 8bit Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org 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 */ -- 2.27.0.rc0.183.gde8f92d652-goog