// SPDX-License-Identifier: GPL-2.0-or-later
|
/*
|
* dma-bufs for virtio exported objects
|
*
|
* Copyright (C) 2020 Google, Inc.
|
*/
|
|
#include <linux/module.h>
|
#include <linux/virtio_dma_buf.h>
|
|
/**
|
* virtio_dma_buf_export - Creates a new dma-buf for a virtio exported object
|
* @exp_info: [in] see dma_buf_export(). ops MUST refer to a dma_buf_ops
|
* struct embedded in a virtio_dma_buf_ops.
|
*
|
* 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 dma_buf_export_info *exp_info)
|
{
|
const struct virtio_dma_buf_ops *virtio_ops =
|
container_of(exp_info->ops,
|
const struct virtio_dma_buf_ops, ops);
|
|
if (!exp_info->ops ||
|
!virtio_ops->get_uuid) {
|
return ERR_PTR(-EINVAL);
|
}
|
|
if (!(IS_ENABLED(CONFIG_CFI_CLANG) && IS_ENABLED(CONFIG_MODULES)) &&
|
exp_info->ops->attach != &virtio_dma_buf_attach)
|
return ERR_PTR(-EINVAL);
|
|
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)
|
{
|
if (IS_ENABLED(CONFIG_CFI_CLANG) && IS_ENABLED(CONFIG_MODULES))
|
return true;
|
|
return dma_buf->ops->attach == &virtio_dma_buf_attach;
|
}
|
EXPORT_SYMBOL(is_virtio_dma_buf);
|
|
/**
|
* virtio_dma_buf_get_uuid - gets a virtio dma-buf's exported object's uuid
|
* @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);
|
|
MODULE_LICENSE("GPL");
|
