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[PATCH v3 1/3] drm: Introduce DRM_MODE_DUMB_KERNEL_MAP flag

Chen-Yu Tsai posted 3 patches 1 week ago
[PATCH v3 1/3] drm: Introduce DRM_MODE_DUMB_KERNEL_MAP flag
Posted by Chen-Yu Tsai 1 week ago 
From: Rob Herring <robh@kernel.org>

Introduce a new flag, DRM_MODE_DUMB_KERNEL_MAP, for struct
drm_mode_create_dumb. This flag is for internal kernel use to indicate
if dumb buffer allocation needs a kernel mapping. This is needed only for
GEM DMA where creating a kernel mapping or not has to be decided at
allocation time because creating a mapping on demand (with vmap()) is not
guaranteed to work.

Several drivers are using reimplementing the GEM DMA helpers because
they distinguish between kernel and userspace allocations to create a
kernel mapping or not. Adding a flag allows migrating these drivers
to the helpers while preserving their existing behavior. These include
exynos, rockchip, and previously mediatek.

Update the callers of drm_mode_dumb_create() to set
drm_mode_dumb_create.flags to appropriate defaults. Currently, flags can
be set to anything by userspace, but is unused within the kernel. Let's
force flags to zero (no kernel mapping) for userspace callers by default.
For in kernel clients, set DRM_MODE_DUMB_KERNEL_MAP by default. Drivers
can override this as needed.

Signed-off-by: Rob Herring <robh@kernel.org>
[wenst@chromium.org: Emit warning (once) if args->flags is not zero]
[wenst@chromium.org: Moved flag def. to include/drm/drm_dumb_buffers.h]
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
---
Changes since v2:
- Switched to drm_warn_once()
- Moved flag definition from include/uapi/ to include/drm/drm_dumb_buffers.h
- Reworded commit message

Changes since v1:
- Emit warning if args->flags is not zero
---
 drivers/gpu/drm/drm_client.c       | 2 ++
 drivers/gpu/drm/drm_dumb_buffers.c | 4 ++++
 include/drm/drm_dumb_buffers.h     | 3 +++
 3 files changed, 9 insertions(+)

diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c
index 46c465bce98c..3d3e61823cc1 100644
--- a/drivers/gpu/drm/drm_client.c
+++ b/drivers/gpu/drm/drm_client.c
@@ -14,6 +14,7 @@
 #include <drm/drm_client_event.h>
 #include <drm/drm_device.h>
 #include <drm/drm_drv.h>
+#include <drm/drm_dumb_buffers.h>
 #include <drm/drm_file.h>
 #include <drm/drm_fourcc.h>
 #include <drm/drm_framebuffer.h>
@@ -404,6 +405,7 @@ drm_client_buffer_create_dumb(struct drm_client_dev *client, u32 width, u32 heig
 	dumb_args.width = width;
 	dumb_args.height = height;
 	dumb_args.bpp = drm_format_info_bpp(info, 0);
+	dumb_args.flags = DRM_MODE_DUMB_KERNEL_MAP;
 	ret = drm_mode_create_dumb(dev, &dumb_args, client->file);
 	if (ret)
 		return ERR_PTR(ret);
diff --git a/drivers/gpu/drm/drm_dumb_buffers.c b/drivers/gpu/drm/drm_dumb_buffers.c
index e2b62e5fb891..60f4c2d08641 100644
--- a/drivers/gpu/drm/drm_dumb_buffers.c
+++ b/drivers/gpu/drm/drm_dumb_buffers.c
@@ -233,6 +233,10 @@ int drm_mode_create_dumb_ioctl(struct drm_device *dev,
 	struct drm_mode_create_dumb *args = data;
 	int err;
 
+	if (args->flags)
+		drm_warn_once(dev, "drm_mode_create_dumb.flags is not zero.\n");
+	args->flags = 0;
+
 	err = drm_mode_create_dumb(dev, args, file_priv);
 	if (err) {
 		args->handle = 0;
diff --git a/include/drm/drm_dumb_buffers.h b/include/drm/drm_dumb_buffers.h
index 1f3a8236fb3d..4657e44533f4 100644
--- a/include/drm/drm_dumb_buffers.h
+++ b/include/drm/drm_dumb_buffers.h
@@ -6,6 +6,9 @@
 struct drm_device;
 struct drm_mode_create_dumb;
 
+/* drm_mode_create_dumb flags for internal use */
+#define DRM_MODE_DUMB_KERNEL_MAP	(1<<0)
+
 int drm_mode_size_dumb(struct drm_device *dev,
 		       struct drm_mode_create_dumb *args,
 		       unsigned long hw_pitch_align,
-- 
2.53.0.1018.g2bb0e51243-goog
Re: [PATCH v3 1/3] drm: Introduce DRM_MODE_DUMB_KERNEL_MAP flag
Posted by Thomas Zimmermann 6 days, 14 hours ago 
Hi

Am 26.03.26 um 11:01 schrieb Chen-Yu Tsai:
> From: Rob Herring <robh@kernel.org>
>
> Introduce a new flag, DRM_MODE_DUMB_KERNEL_MAP, for struct
> drm_mode_create_dumb. This flag is for internal kernel use to indicate
> if dumb buffer allocation needs a kernel mapping. This is needed only for
> GEM DMA where creating a kernel mapping or not has to be decided at
> allocation time because creating a mapping on demand (with vmap()) is not
> guaranteed to work.

I still don't understand what you're trying to achieve. As I pointed 
out, ever driver's memory manager potentially requires a vmap. Passing 
around flags will not solve that problem. If vmap is not possible, the 
driver should not provide the vmap callbacks in the first place.

Best regards
Thomas

>
> Several drivers are using reimplementing the GEM DMA helpers because
> they distinguish between kernel and userspace allocations to create a
> kernel mapping or not. Adding a flag allows migrating these drivers
> to the helpers while preserving their existing behavior. These include
> exynos, rockchip, and previously mediatek.
>
> Update the callers of drm_mode_dumb_create() to set
> drm_mode_dumb_create.flags to appropriate defaults. Currently, flags can
> be set to anything by userspace, but is unused within the kernel. Let's
> force flags to zero (no kernel mapping) for userspace callers by default.
> For in kernel clients, set DRM_MODE_DUMB_KERNEL_MAP by default. Drivers
> can override this as needed.
>
> Signed-off-by: Rob Herring <robh@kernel.org>
> [wenst@chromium.org: Emit warning (once) if args->flags is not zero]
> [wenst@chromium.org: Moved flag def. to include/drm/drm_dumb_buffers.h]
> Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
> ---
> Changes since v2:
> - Switched to drm_warn_once()
> - Moved flag definition from include/uapi/ to include/drm/drm_dumb_buffers.h
> - Reworded commit message
>
> Changes since v1:
> - Emit warning if args->flags is not zero
> ---
>   drivers/gpu/drm/drm_client.c       | 2 ++
>   drivers/gpu/drm/drm_dumb_buffers.c | 4 ++++
>   include/drm/drm_dumb_buffers.h     | 3 +++
>   3 files changed, 9 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c
> index 46c465bce98c..3d3e61823cc1 100644
> --- a/drivers/gpu/drm/drm_client.c
> +++ b/drivers/gpu/drm/drm_client.c
> @@ -14,6 +14,7 @@
>   #include <drm/drm_client_event.h>
>   #include <drm/drm_device.h>
>   #include <drm/drm_drv.h>
> +#include <drm/drm_dumb_buffers.h>
>   #include <drm/drm_file.h>
>   #include <drm/drm_fourcc.h>
>   #include <drm/drm_framebuffer.h>
> @@ -404,6 +405,7 @@ drm_client_buffer_create_dumb(struct drm_client_dev *client, u32 width, u32 heig
>   	dumb_args.width = width;
>   	dumb_args.height = height;
>   	dumb_args.bpp = drm_format_info_bpp(info, 0);
> +	dumb_args.flags = DRM_MODE_DUMB_KERNEL_MAP;
>   	ret = drm_mode_create_dumb(dev, &dumb_args, client->file);
>   	if (ret)
>   		return ERR_PTR(ret);
> diff --git a/drivers/gpu/drm/drm_dumb_buffers.c b/drivers/gpu/drm/drm_dumb_buffers.c
> index e2b62e5fb891..60f4c2d08641 100644
> --- a/drivers/gpu/drm/drm_dumb_buffers.c
> +++ b/drivers/gpu/drm/drm_dumb_buffers.c
> @@ -233,6 +233,10 @@ int drm_mode_create_dumb_ioctl(struct drm_device *dev,
>   	struct drm_mode_create_dumb *args = data;
>   	int err;
>   
> +	if (args->flags)
> +		drm_warn_once(dev, "drm_mode_create_dumb.flags is not zero.\n");
> +	args->flags = 0;
> +
>   	err = drm_mode_create_dumb(dev, args, file_priv);
>   	if (err) {
>   		args->handle = 0;
> diff --git a/include/drm/drm_dumb_buffers.h b/include/drm/drm_dumb_buffers.h
> index 1f3a8236fb3d..4657e44533f4 100644
> --- a/include/drm/drm_dumb_buffers.h
> +++ b/include/drm/drm_dumb_buffers.h
> @@ -6,6 +6,9 @@
>   struct drm_device;
>   struct drm_mode_create_dumb;
>   
> +/* drm_mode_create_dumb flags for internal use */
> +#define DRM_MODE_DUMB_KERNEL_MAP	(1<<0)
> +
>   int drm_mode_size_dumb(struct drm_device *dev,
>   		       struct drm_mode_create_dumb *args,
>   		       unsigned long hw_pitch_align,

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com
GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)
Re: [PATCH v3 1/3] drm: Introduce DRM_MODE_DUMB_KERNEL_MAP flag
Posted by Chen-Yu Tsai 6 days, 12 hours ago 
On Fri, Mar 27, 2026 at 3:21 PM Thomas Zimmermann <tzimmermann@suse.de> wrote:
>
> Hi
>
> Am 26.03.26 um 11:01 schrieb Chen-Yu Tsai:
> > From: Rob Herring <robh@kernel.org>
> >
> > Introduce a new flag, DRM_MODE_DUMB_KERNEL_MAP, for struct
> > drm_mode_create_dumb. This flag is for internal kernel use to indicate
> > if dumb buffer allocation needs a kernel mapping. This is needed only for
> > GEM DMA where creating a kernel mapping or not has to be decided at
> > allocation time because creating a mapping on demand (with vmap()) is not
> > guaranteed to work.
>
> I still don't understand what you're trying to achieve. As I pointed
> out, ever driver's memory manager potentially requires a vmap. Passing
> around flags will not solve that problem. If vmap is not possible, the
> driver should not provide the vmap callbacks in the first place.

I'm trying to convert the Rockchip and Exynos drivers to the GEM DMA
helpers. Both have their reasons for not using the helpers, one of them
being that the DRM device is not the DMA device. This is already fixed
by my other series. Both drivers also set DMA_ATTR_NO_KERNEL_MAPPING
for buffer allocations other than the one used by fb_helper.

Exynos's GEM implementation also sets extra DMA attributes at the
allocation phase for their custom GEM create ioctl. But otherwise
exynos is just reimplementing all the GEM DMA helpers in almost
identical fashion. And to your point, exynos does not provide the
vmap callback.

Rockchip's GEM implementation splits the code path between DMA and
IOMMU usage as it needs to attach and detach the DMA device from the
IOMMU domain on the fly. This predates the DMA IOMMU framework. This
GEM implementation provides the vmap callback, which will fail for
direct DMA allocations without the kernel mapping.

There's also something fishy about Rockchip's DRM driver. It's using
fbdev-dma, even though it's not based on the GEM DMA helpers or even
drm_gem_dma_object.

As you are against changing the existing *_dumb_create() interface,
I will look into reusing drm_gem_dma_object with driver-specific
functions. I believe I will need to keep patch 2 adding dma_attrs
though. Would that be acceptable?

Once again, thank you for your patience.


ChenYu


> Best regards
> Thomas
>
> >
> > Several drivers are using reimplementing the GEM DMA helpers because
> > they distinguish between kernel and userspace allocations to create a
> > kernel mapping or not. Adding a flag allows migrating these drivers
> > to the helpers while preserving their existing behavior. These include
> > exynos, rockchip, and previously mediatek.
> >
> > Update the callers of drm_mode_dumb_create() to set
> > drm_mode_dumb_create.flags to appropriate defaults. Currently, flags can
> > be set to anything by userspace, but is unused within the kernel. Let's
> > force flags to zero (no kernel mapping) for userspace callers by default.
> > For in kernel clients, set DRM_MODE_DUMB_KERNEL_MAP by default. Drivers
> > can override this as needed.
> >
> > Signed-off-by: Rob Herring <robh@kernel.org>
> > [wenst@chromium.org: Emit warning (once) if args->flags is not zero]
> > [wenst@chromium.org: Moved flag def. to include/drm/drm_dumb_buffers.h]
> > Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
> > ---
> > Changes since v2:
> > - Switched to drm_warn_once()
> > - Moved flag definition from include/uapi/ to include/drm/drm_dumb_buffers.h
> > - Reworded commit message
> >
> > Changes since v1:
> > - Emit warning if args->flags is not zero
> > ---
> >   drivers/gpu/drm/drm_client.c       | 2 ++
> >   drivers/gpu/drm/drm_dumb_buffers.c | 4 ++++
> >   include/drm/drm_dumb_buffers.h     | 3 +++
> >   3 files changed, 9 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c
> > index 46c465bce98c..3d3e61823cc1 100644
> > --- a/drivers/gpu/drm/drm_client.c
> > +++ b/drivers/gpu/drm/drm_client.c
> > @@ -14,6 +14,7 @@
> >   #include <drm/drm_client_event.h>
> >   #include <drm/drm_device.h>
> >   #include <drm/drm_drv.h>
> > +#include <drm/drm_dumb_buffers.h>
> >   #include <drm/drm_file.h>
> >   #include <drm/drm_fourcc.h>
> >   #include <drm/drm_framebuffer.h>
> > @@ -404,6 +405,7 @@ drm_client_buffer_create_dumb(struct drm_client_dev *client, u32 width, u32 heig
> >       dumb_args.width = width;
> >       dumb_args.height = height;
> >       dumb_args.bpp = drm_format_info_bpp(info, 0);
> > +     dumb_args.flags = DRM_MODE_DUMB_KERNEL_MAP;
> >       ret = drm_mode_create_dumb(dev, &dumb_args, client->file);
> >       if (ret)
> >               return ERR_PTR(ret);
> > diff --git a/drivers/gpu/drm/drm_dumb_buffers.c b/drivers/gpu/drm/drm_dumb_buffers.c
> > index e2b62e5fb891..60f4c2d08641 100644
> > --- a/drivers/gpu/drm/drm_dumb_buffers.c
> > +++ b/drivers/gpu/drm/drm_dumb_buffers.c
> > @@ -233,6 +233,10 @@ int drm_mode_create_dumb_ioctl(struct drm_device *dev,
> >       struct drm_mode_create_dumb *args = data;
> >       int err;
> >
> > +     if (args->flags)
> > +             drm_warn_once(dev, "drm_mode_create_dumb.flags is not zero.\n");
> > +     args->flags = 0;
> > +
> >       err = drm_mode_create_dumb(dev, args, file_priv);
> >       if (err) {
> >               args->handle = 0;
> > diff --git a/include/drm/drm_dumb_buffers.h b/include/drm/drm_dumb_buffers.h
> > index 1f3a8236fb3d..4657e44533f4 100644
> > --- a/include/drm/drm_dumb_buffers.h
> > +++ b/include/drm/drm_dumb_buffers.h
> > @@ -6,6 +6,9 @@
> >   struct drm_device;
> >   struct drm_mode_create_dumb;
> >
> > +/* drm_mode_create_dumb flags for internal use */
> > +#define DRM_MODE_DUMB_KERNEL_MAP     (1<<0)
> > +
> >   int drm_mode_size_dumb(struct drm_device *dev,
> >                      struct drm_mode_create_dumb *args,
> >                      unsigned long hw_pitch_align,
>
> --
> --
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com
> GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)
>
>
Re: [PATCH v3 1/3] drm: Introduce DRM_MODE_DUMB_KERNEL_MAP flag
Posted by Thomas Zimmermann 3 days, 15 hours ago 
Hi

Am 27.03.26 um 10:38 schrieb Chen-Yu Tsai:
> On Fri, Mar 27, 2026 at 3:21 PM Thomas Zimmermann <tzimmermann@suse.de> wrote:
>> Hi
>>
>> Am 26.03.26 um 11:01 schrieb Chen-Yu Tsai:
>>> From: Rob Herring <robh@kernel.org>
>>>
>>> Introduce a new flag, DRM_MODE_DUMB_KERNEL_MAP, for struct
>>> drm_mode_create_dumb. This flag is for internal kernel use to indicate
>>> if dumb buffer allocation needs a kernel mapping. This is needed only for
>>> GEM DMA where creating a kernel mapping or not has to be decided at
>>> allocation time because creating a mapping on demand (with vmap()) is not
>>> guaranteed to work.
>> I still don't understand what you're trying to achieve. As I pointed
>> out, ever driver's memory manager potentially requires a vmap. Passing
>> around flags will not solve that problem. If vmap is not possible, the
>> driver should not provide the vmap callbacks in the first place.
> I'm trying to convert the Rockchip and Exynos drivers to the GEM DMA

Ok.

> helpers. Both have their reasons for not using the helpers, one of them
> being that the DRM device is not the DMA device. This is already fixed
> by my other series. Both drivers also set DMA_ATTR_NO_KERNEL_MAPPING
> for buffer allocations other than the one used by fb_helper.
>
> Exynos's GEM implementation also sets extra DMA attributes at the
> allocation phase for their custom GEM create ioctl. But otherwise
> exynos is just reimplementing all the GEM DMA helpers in almost
> identical fashion. And to your point, exynos does not provide the
> vmap callback.
>
> Rockchip's GEM implementation splits the code path between DMA and
> IOMMU usage as it needs to attach and detach the DMA device from the
> IOMMU domain on the fly. This predates the DMA IOMMU framework. This
> GEM implementation provides the vmap callback, which will fail for
> direct DMA allocations without the kernel mapping.
>
> There's also something fishy about Rockchip's DRM driver. It's using
> fbdev-dma, even though it's not based on the GEM DMA helpers or even
> drm_gem_dma_object.

Oh!


>
> As you are against changing the existing *_dumb_create() interface,
> I will look into reusing drm_gem_dma_object with driver-specific
> functions. I believe I will need to keep patch 2 adding dma_attrs
> though. Would that be acceptable?

I think so. Sharing code is good, but I don't like these flags that 
change a function's overall behavior. I think that's the case here. 
Flags are OK when they extent or modify a little detail, but extensively 
used the affected code becomes unmaintainable. It's better to have a 
dedicated function for such special cases. What you could do is to 
provide a separate helper that allocates an object with the specific 
vmap behavior and use it for these drivers. The allocator function 
should also set dedicated gem-object funcs w/o vmap/vunmap where 
possible.  Drivers can then pick the helpers.

If you 're looking for an example, take a look at commit 660cd44659a0 
("drm/shmem-helper: Import dmabuf without mapping its sg_table")  and 
it's patch series.  With gem-shmem, many drivers don't work correctly 
with the sg-table imported.  The commit provides them with a separate 
import helper that takes care of this.

Best regards
Thomas


>
> Once again, thank you for your patience.
>
>
> ChenYu
>
>
>> Best regards
>> Thomas
>>
>>> Several drivers are using reimplementing the GEM DMA helpers because
>>> they distinguish between kernel and userspace allocations to create a
>>> kernel mapping or not. Adding a flag allows migrating these drivers
>>> to the helpers while preserving their existing behavior. These include
>>> exynos, rockchip, and previously mediatek.
>>>
>>> Update the callers of drm_mode_dumb_create() to set
>>> drm_mode_dumb_create.flags to appropriate defaults. Currently, flags can
>>> be set to anything by userspace, but is unused within the kernel. Let's
>>> force flags to zero (no kernel mapping) for userspace callers by default.
>>> For in kernel clients, set DRM_MODE_DUMB_KERNEL_MAP by default. Drivers
>>> can override this as needed.
>>>
>>> Signed-off-by: Rob Herring <robh@kernel.org>
>>> [wenst@chromium.org: Emit warning (once) if args->flags is not zero]
>>> [wenst@chromium.org: Moved flag def. to include/drm/drm_dumb_buffers.h]
>>> Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
>>> ---
>>> Changes since v2:
>>> - Switched to drm_warn_once()
>>> - Moved flag definition from include/uapi/ to include/drm/drm_dumb_buffers.h
>>> - Reworded commit message
>>>
>>> Changes since v1:
>>> - Emit warning if args->flags is not zero
>>> ---
>>>    drivers/gpu/drm/drm_client.c       | 2 ++
>>>    drivers/gpu/drm/drm_dumb_buffers.c | 4 ++++
>>>    include/drm/drm_dumb_buffers.h     | 3 +++
>>>    3 files changed, 9 insertions(+)
>>>
>>> diff --git a/drivers/gpu/drm/drm_client.c b/drivers/gpu/drm/drm_client.c
>>> index 46c465bce98c..3d3e61823cc1 100644
>>> --- a/drivers/gpu/drm/drm_client.c
>>> +++ b/drivers/gpu/drm/drm_client.c
>>> @@ -14,6 +14,7 @@
>>>    #include <drm/drm_client_event.h>
>>>    #include <drm/drm_device.h>
>>>    #include <drm/drm_drv.h>
>>> +#include <drm/drm_dumb_buffers.h>
>>>    #include <drm/drm_file.h>
>>>    #include <drm/drm_fourcc.h>
>>>    #include <drm/drm_framebuffer.h>
>>> @@ -404,6 +405,7 @@ drm_client_buffer_create_dumb(struct drm_client_dev *client, u32 width, u32 heig
>>>        dumb_args.width = width;
>>>        dumb_args.height = height;
>>>        dumb_args.bpp = drm_format_info_bpp(info, 0);
>>> +     dumb_args.flags = DRM_MODE_DUMB_KERNEL_MAP;
>>>        ret = drm_mode_create_dumb(dev, &dumb_args, client->file);
>>>        if (ret)
>>>                return ERR_PTR(ret);
>>> diff --git a/drivers/gpu/drm/drm_dumb_buffers.c b/drivers/gpu/drm/drm_dumb_buffers.c
>>> index e2b62e5fb891..60f4c2d08641 100644
>>> --- a/drivers/gpu/drm/drm_dumb_buffers.c
>>> +++ b/drivers/gpu/drm/drm_dumb_buffers.c
>>> @@ -233,6 +233,10 @@ int drm_mode_create_dumb_ioctl(struct drm_device *dev,
>>>        struct drm_mode_create_dumb *args = data;
>>>        int err;
>>>
>>> +     if (args->flags)
>>> +             drm_warn_once(dev, "drm_mode_create_dumb.flags is not zero.\n");
>>> +     args->flags = 0;
>>> +
>>>        err = drm_mode_create_dumb(dev, args, file_priv);
>>>        if (err) {
>>>                args->handle = 0;
>>> diff --git a/include/drm/drm_dumb_buffers.h b/include/drm/drm_dumb_buffers.h
>>> index 1f3a8236fb3d..4657e44533f4 100644
>>> --- a/include/drm/drm_dumb_buffers.h
>>> +++ b/include/drm/drm_dumb_buffers.h
>>> @@ -6,6 +6,9 @@
>>>    struct drm_device;
>>>    struct drm_mode_create_dumb;
>>>
>>> +/* drm_mode_create_dumb flags for internal use */
>>> +#define DRM_MODE_DUMB_KERNEL_MAP     (1<<0)
>>> +
>>>    int drm_mode_size_dumb(struct drm_device *dev,
>>>                       struct drm_mode_create_dumb *args,
>>>                       unsigned long hw_pitch_align,
>> --
>> --
>> Thomas Zimmermann
>> Graphics Driver Developer
>> SUSE Software Solutions Germany GmbH
>> Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com
>> GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)
>>
>>

-- 
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com
GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)

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