2019-03-29 16:53:46

by Andrew Davis

Subject: [PATCH] dma-buf: Make mmap callback actually optional

The docs state the callback is optional but it is not, make it optional.

Signed-off-by: Andrew F. Davis <[email protected]>
---
drivers/dma-buf/dma-buf.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
index 7c858020d14b..4d4ae9fe9ac8 100644
--- a/drivers/dma-buf/dma-buf.c
+++ b/drivers/dma-buf/dma-buf.c
@@ -90,6 +90,10 @@ static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma)

dmabuf = file->private_data;

+ /* check if buffer supports mmap */
+ if (!dmabuf->ops->mmap)
+ return -EINVAL;
+
/* check for overflowing the buffer's size */
if (vma->vm_pgoff + vma_pages(vma) >
dmabuf->size >> PAGE_SHIFT)
@@ -404,8 +408,7 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info)
|| !exp_info->ops
|| !exp_info->ops->map_dma_buf
|| !exp_info->ops->unmap_dma_buf
- || !exp_info->ops->release
- || !exp_info->ops->mmap)) {
+ || !exp_info->ops->release)) {
return ERR_PTR(-EINVAL);
}

@@ -906,6 +909,10 @@ int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma,
if (WARN_ON(!dmabuf || !vma))
return -EINVAL;

+ /* check if buffer supports mmap */
+ if (!dmabuf->ops->mmap)
+ return -EINVAL;
+
/* check for offset overflow */
if (pgoff + vma_pages(vma) < pgoff)
return -EOVERFLOW;
--
2.21.0

2019-04-01 07:14:41

by Daniel Vetter

Subject: Re: [PATCH] dma-buf: Make mmap callback actually optional

On Fri, Mar 29, 2019 at 11:52:01AM -0500, Andrew F. Davis wrote:
> The docs state the callback is optional but it is not, make it optional.
>
> Signed-off-by: Andrew F. Davis <[email protected]>

There's a bunch of dummy mmap implementations we could remove with this,
would be nice to follow up.

Reviewed-by: Daniel Vetter <[email protected]>

> ---
> drivers/dma-buf/dma-buf.c | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
> index 7c858020d14b..4d4ae9fe9ac8 100644
> --- a/drivers/dma-buf/dma-buf.c
> +++ b/drivers/dma-buf/dma-buf.c
> @@ -90,6 +90,10 @@ static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma)
>
> dmabuf = file->private_data;
>
> + /* check if buffer supports mmap */
> + if (!dmabuf->ops->mmap)
> + return -EINVAL;
> +
> /* check for overflowing the buffer's size */
> if (vma->vm_pgoff + vma_pages(vma) >
> dmabuf->size >> PAGE_SHIFT)
> @@ -404,8 +408,7 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info)
> || !exp_info->ops
> || !exp_info->ops->map_dma_buf
> || !exp_info->ops->unmap_dma_buf
> - || !exp_info->ops->release
> - || !exp_info->ops->mmap)) {
> + || !exp_info->ops->release)) {
> return ERR_PTR(-EINVAL);
> }
>
> @@ -906,6 +909,10 @@ int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma,
> if (WARN_ON(!dmabuf || !vma))
> return -EINVAL;
>
> + /* check if buffer supports mmap */
> + if (!dmabuf->ops->mmap)
> + return -EINVAL;
> +
> /* check for offset overflow */
> if (pgoff + vma_pages(vma) < pgoff)
> return -EOVERFLOW;
> --
> 2.21.0
>
> _______________________________________________
> dri-devel mailing list
> [email protected]
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

2019-04-01 13:28:45

by Andrew Davis

Subject: Re: [PATCH] dma-buf: Make mmap callback actually optional

On 4/1/19 2:13 AM, Daniel Vetter wrote:
> On Fri, Mar 29, 2019 at 11:52:01AM -0500, Andrew F. Davis wrote:
>> The docs state the callback is optional but it is not, make it optional.
>>
>> Signed-off-by: Andrew F. Davis <[email protected]>
>
> There's a bunch of dummy mmap implementations we could remove with this,
> would be nice to follow up.
>

Was cleaning up some dummy kmap implementations when I found that many
had dummy mmap also, so plan was if this goes in I'll be able to zap
them both in one go. That or actually add valid kmap where appropriate.
Either way will be following up.

Andrew

> Reviewed-by: Daniel Vetter <[email protected]>
>
>> ---
>> drivers/dma-buf/dma-buf.c | 11 +++++++++--
>> 1 file changed, 9 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
>> index 7c858020d14b..4d4ae9fe9ac8 100644
>> --- a/drivers/dma-buf/dma-buf.c
>> +++ b/drivers/dma-buf/dma-buf.c
>> @@ -90,6 +90,10 @@ static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma)
>>
>> dmabuf = file->private_data;
>>
>> + /* check if buffer supports mmap */
>> + if (!dmabuf->ops->mmap)
>> + return -EINVAL;
>> +
>> /* check for overflowing the buffer's size */
>> if (vma->vm_pgoff + vma_pages(vma) >
>> dmabuf->size >> PAGE_SHIFT)
>> @@ -404,8 +408,7 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info)
>> || !exp_info->ops
>> || !exp_info->ops->map_dma_buf
>> || !exp_info->ops->unmap_dma_buf
>> - || !exp_info->ops->release
>> - || !exp_info->ops->mmap)) {
>> + || !exp_info->ops->release)) {
>> return ERR_PTR(-EINVAL);
>> }
>>
>> @@ -906,6 +909,10 @@ int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma,
>> if (WARN_ON(!dmabuf || !vma))
>> return -EINVAL;
>>
>> + /* check if buffer supports mmap */
>> + if (!dmabuf->ops->mmap)
>> + return -EINVAL;
>> +
>> /* check for offset overflow */
>> if (pgoff + vma_pages(vma) < pgoff)
>> return -EOVERFLOW;
>> --
>> 2.21.0
>>
>> _______________________________________________
>> dri-devel mailing list
>> [email protected]
>> https://lists.freedesktop.org/mailman/listinfo/dri-devel
>

2019-04-01 13:39:40

by Christian König

Subject: Re: [PATCH] dma-buf: Make mmap callback actually optional

Am 29.03.19 um 17:52 schrieb Andrew F. Davis:
> The docs state the callback is optional but it is not, make it optional.
>
> Signed-off-by: Andrew F. Davis <[email protected]>

Reviewed-by: Christian König <[email protected]>

> ---
> drivers/dma-buf/dma-buf.c | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
> index 7c858020d14b..4d4ae9fe9ac8 100644
> --- a/drivers/dma-buf/dma-buf.c
> +++ b/drivers/dma-buf/dma-buf.c
> @@ -90,6 +90,10 @@ static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma)
>
> dmabuf = file->private_data;
>
> + /* check if buffer supports mmap */
> + if (!dmabuf->ops->mmap)
> + return -EINVAL;
> +
> /* check for overflowing the buffer's size */
> if (vma->vm_pgoff + vma_pages(vma) >
> dmabuf->size >> PAGE_SHIFT)
> @@ -404,8 +408,7 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info)
> || !exp_info->ops
> || !exp_info->ops->map_dma_buf
> || !exp_info->ops->unmap_dma_buf
> - || !exp_info->ops->release
> - || !exp_info->ops->mmap)) {
> + || !exp_info->ops->release)) {
> return ERR_PTR(-EINVAL);
> }
>
> @@ -906,6 +909,10 @@ int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma,
> if (WARN_ON(!dmabuf || !vma))
> return -EINVAL;
>
> + /* check if buffer supports mmap */
> + if (!dmabuf->ops->mmap)
> + return -EINVAL;
> +
> /* check for offset overflow */
> if (pgoff + vma_pages(vma) < pgoff)
> return -EOVERFLOW;

2019-04-03 06:32:05

by Sumit Semwal

Subject: Re: [PATCH] dma-buf: Make mmap callback actually optional

Hi Andrew,

On Mon, 1 Apr 2019 at 20:38, Christian König
<[email protected]> wrote:
>
> Am 29.03.19 um 17:52 schrieb Andrew F. Davis:
> > The docs state the callback is optional but it is not, make it optional.
> >
> > Signed-off-by: Andrew F. Davis <[email protected]>
>
> Reviewed-by: Christian König <[email protected]>

Thanks for the patch; I will queue it up within this week (at a
conference atm, but will squeeze out time for doing this).

>
> > ---
> > drivers/dma-buf/dma-buf.c | 11 +++++++++--
> > 1 file changed, 9 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c
> > index 7c858020d14b..4d4ae9fe9ac8 100644
> > --- a/drivers/dma-buf/dma-buf.c
> > +++ b/drivers/dma-buf/dma-buf.c
> > @@ -90,6 +90,10 @@ static int dma_buf_mmap_internal(struct file *file, struct vm_area_struct *vma)
> >
> > dmabuf = file->private_data;
> >
> > + /* check if buffer supports mmap */
> > + if (!dmabuf->ops->mmap)
> > + return -EINVAL;
> > +
> > /* check for overflowing the buffer's size */
> > if (vma->vm_pgoff + vma_pages(vma) >
> > dmabuf->size >> PAGE_SHIFT)
> > @@ -404,8 +408,7 @@ struct dma_buf *dma_buf_export(const struct dma_buf_export_info *exp_info)
> > || !exp_info->ops
> > || !exp_info->ops->map_dma_buf
> > || !exp_info->ops->unmap_dma_buf
> > - || !exp_info->ops->release
> > - || !exp_info->ops->mmap)) {
> > + || !exp_info->ops->release)) {
> > return ERR_PTR(-EINVAL);
> > }
> >
> > @@ -906,6 +909,10 @@ int dma_buf_mmap(struct dma_buf *dmabuf, struct vm_area_struct *vma,
> > if (WARN_ON(!dmabuf || !vma))
> > return -EINVAL;
> >
> > + /* check if buffer supports mmap */
> > + if (!dmabuf->ops->mmap)
> > + return -EINVAL;
> > +
> > /* check for offset overflow */
> > if (pgoff + vma_pages(vma) < pgoff)
> > return -EOVERFLOW;
>

Best,
Sumit.