[PATCH 1/5] drm: introduce sync objects (v3)

[Dave Airlie]

On 25 May 2017 at 18:30, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> On Wed, May 24, 2017 at 05:06:11PM +1000, Dave Airlie wrote:
>> From: Dave Airlie <airlied at redhat.com>
>>
>> Sync objects are new toplevel drm object, that contain a
>> pointer to a fence. This fence can be updated via command
>> submission ioctls via drivers.
>>
>> There is also a generic wait obj API modelled on the vulkan
>> wait API (with code modelled on some amdgpu code).
>>
>> These objects can be converted to an opaque fd that can be
>> passes between processes.
>>
>> v2: rename reference/unreference to put/get (Chris)
>> fix leaked reference (David Zhou)
>> drop mutex in favour of cmpxchg (Chris)
>> v3: cleanups from danvet, rebase on drm_fops rename
>> check fd_flags is 0 in ioctls.
>>
>> Reviewed-by: Sean Paul <seanpaul at chromium.org>
>> Signed-off-by: Dave Airlie <airlied at redhat.com>
>> ---
>> diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
>> index 42d9f64..96c5c78 100644
>> --- a/include/uapi/drm/drm.h
>> +++ b/include/uapi/drm/drm.h
>> @@ -648,6 +648,7 @@ struct drm_gem_open {
>>  #define DRM_CAP_ADDFB2_MODIFIERS     0x10
>>  #define DRM_CAP_PAGE_FLIP_TARGET     0x11
>>  #define DRM_CAP_CRTC_IN_VBLANK_EVENT 0x12
>> +#define DRM_CAP_SYNCOBJ              0x13
>>
>>  /** DRM_IOCTL_GET_CAP ioctl argument type */
>>  struct drm_get_cap {
>> @@ -697,6 +698,24 @@ struct drm_prime_handle {
>>       __s32 fd;
>>  };
>>
>> +struct drm_syncobj_create {
>> +     __u32 handle;
>> +     __u32 flags;
>> +};
>> +
>> +struct drm_syncobj_destroy {
>> +     __u32 handle;
>> +     __u32 pad;
>> +};
>> +
>> +struct drm_syncobj_handle {
>> +     __u32 handle;
>> +     __u32 flags;
>> +
>> +     __s32 fd;
>> +     __u32 pad;
>> +};
>> +
>>  #if defined(__cplusplus)
>>  }
>>  #endif
>> @@ -815,6 +834,11 @@ extern "C" {
>>  #define DRM_IOCTL_MODE_CREATEPROPBLOB        DRM_IOWR(0xBD, struct drm_mode_create_blob)
>>  #define DRM_IOCTL_MODE_DESTROYPROPBLOB       DRM_IOWR(0xBE, struct drm_mode_destroy_blob)
>>
>> +#define DRM_IOCTL_SYNCOBJ_CREATE     DRM_IOWR(0xBF, struct drm_syncobj_create)
>> +#define DRM_IOCTL_SYNCOBJ_DESTROY    DRM_IOWR(0xC0, struct drm_syncobj_destroy)
>
> These two only need DRM_IOW.

They do now, but at least create takes some flags, destroy is probably
fine. are we okay to change these flags later?

I can never remember and I'd rather not have to think about it too much.
>
> With that,
> Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>

Thanks,
Dave.