lkml.org 
[lkml]   [2018]   [Jan]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v3] staging: android: ion: Add implementation of dma_buf_vmap and dma_buf_vunmap
On Wed, Jan 31, 2018 at 02:03:42PM +0200, Alexey Skidanov wrote:
> Any driver may access shared buffers, created by ion, using dma_buf_vmap and
> dma_buf_vunmap dma-buf API that maps/unmaps previosuly allocated buffers into
> the kernel virtual address space. The implementation of these API is missing in
> the current ion implementation.
>
> Signed-off-by: Alexey Skidanov <alexey.skidanov@intel.com>
> ---

No review from any other Intel developers? :(

Anyway, what in-tree driver needs access to these functions?

And are you sure that you don't need to do any "real" logic in the
vmap/vunmap calls? That feels like there would be some reference
counting problems here.

> drivers/staging/android/ion/ion.c | 13 +++++++++++++
> 1 file changed, 13 insertions(+)
>
> diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c
> index f480885..4f1dc7f 100644
> --- a/drivers/staging/android/ion/ion.c
> +++ b/drivers/staging/android/ion/ion.c
> @@ -327,6 +327,17 @@ static void ion_dma_buf_kunmap(struct dma_buf *dmabuf, unsigned long offset,
> {
> }
>
> +static void *ion_dma_buf_vmap(struct dma_buf *dmabuf)
> +{
> + struct ion_buffer *buffer = dmabuf->priv;
> +
> + return buffer->vaddr;

Just call ion_dma_buf_kmap(dmabuf, 0)?

Again, please get this reviewed by someone else in Intel first. Don't
ignore the resources you have, to do so would be foolish :)

thanks,

greg k-h

\
 
 \ /
  Last update: 2018-01-31 14:01    [W:0.065 / U:0.052 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site