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88 lines
2.2 KiB
88 lines
2.2 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
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/* |
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* dma-bufs for virtio exported objects |
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* |
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* Copyright (C) 2020 Google, Inc. |
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*/ |
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#include <linux/module.h> |
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#include <linux/virtio_dma_buf.h> |
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/** |
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* virtio_dma_buf_export - Creates a new dma-buf for a virtio exported object |
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* @exp_info: [in] see dma_buf_export(). ops MUST refer to a dma_buf_ops |
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* struct embedded in a virtio_dma_buf_ops. |
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* |
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* This wraps dma_buf_export() to allow virtio drivers to create a dma-buf |
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* for an virtio exported object that can be queried by other virtio drivers |
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* for the object's UUID. |
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*/ |
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struct dma_buf *virtio_dma_buf_export |
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(const struct dma_buf_export_info *exp_info) |
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{ |
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const struct virtio_dma_buf_ops *virtio_ops = |
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container_of(exp_info->ops, |
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const struct virtio_dma_buf_ops, ops); |
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if (!exp_info->ops || |
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exp_info->ops->attach != &virtio_dma_buf_attach || |
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!virtio_ops->get_uuid) { |
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return ERR_PTR(-EINVAL); |
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} |
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return dma_buf_export(exp_info); |
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} |
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EXPORT_SYMBOL(virtio_dma_buf_export); |
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/** |
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* virtio_dma_buf_attach - mandatory attach callback for virtio dma-bufs |
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*/ |
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int virtio_dma_buf_attach(struct dma_buf *dma_buf, |
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struct dma_buf_attachment *attach) |
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{ |
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int ret; |
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const struct virtio_dma_buf_ops *ops = |
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container_of(dma_buf->ops, |
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const struct virtio_dma_buf_ops, ops); |
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if (ops->device_attach) { |
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ret = ops->device_attach(dma_buf, attach); |
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if (ret) |
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return ret; |
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} |
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return 0; |
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} |
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EXPORT_SYMBOL(virtio_dma_buf_attach); |
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/** |
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* is_virtio_dma_buf - returns true if the given dma-buf is a virtio dma-buf |
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* @dma_buf: buffer to query |
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*/ |
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bool is_virtio_dma_buf(struct dma_buf *dma_buf) |
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{ |
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return dma_buf->ops->attach == &virtio_dma_buf_attach; |
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} |
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EXPORT_SYMBOL(is_virtio_dma_buf); |
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/** |
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* virtio_dma_buf_get_uuid - gets a virtio dma-buf's exported object's uuid |
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* @dma_buf: [in] buffer to query |
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* @uuid: [out] the uuid |
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* |
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* Returns: 0 on success, negative on failure. |
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*/ |
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int virtio_dma_buf_get_uuid(struct dma_buf *dma_buf, |
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uuid_t *uuid) |
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{ |
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const struct virtio_dma_buf_ops *ops = |
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container_of(dma_buf->ops, |
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const struct virtio_dma_buf_ops, ops); |
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if (!is_virtio_dma_buf(dma_buf)) |
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return -EINVAL; |
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return ops->get_uuid(dma_buf, uuid); |
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} |
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EXPORT_SYMBOL(virtio_dma_buf_get_uuid); |
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MODULE_LICENSE("GPL");
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