Re: [PATCH v4 8/9] xen/gntdev: Implement dma-buf export functionality
From: Boris Ostrovsky
Date: Fri Jun 15 2018 - 17:02:58 EST
On 06/15/2018 02:27 AM, Oleksandr Andrushchenko wrote:
> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>
>
> 1. Create a dma-buf from grant references provided by the foreign
> domain. By default dma-buf is backed by system memory pages, but
> by providing GNTDEV_DMA_FLAG_XXX flags it can also be created
> as a DMA write-combine/coherent buffer, e.g. allocated with
> corresponding dma_alloc_xxx API.
> Export the resulting buffer as a new dma-buf.
>
> 2. Implement waiting for the dma-buf to be released: block until the
> dma-buf with the file descriptor provided is released.
> If within the time-out provided the buffer is not released then
> -ETIMEDOUT error is returned. If the buffer with the file descriptor
> does not exist or has already been released, then -ENOENT is
> returned. For valid file descriptors this must not be treated as
> error.
>
> 3. Make gntdev's common code and structures available to dma-buf.
>
> Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>