Commit ffa9443f authored by Jason Ekstrand's avatar Jason Ekstrand Committed by Dave Airlie
Browse files

drm/syncobj: Add a signal ioctl (v3) 



This IOCTL provides a mechanism for userspace to trigger a sync object
directly.  There are other ways that userspace can trigger a syncobj
such as submitting a dummy batch somewhere or hanging on to a triggered
sync_file and doing an import.  This just provides an easy way to
manually trigger the sync object without weird hacks.

The motivation for this IOCTL is Vulkan fences.  Vulkan lets you create
a fence already in the signaled state so that you can wait on it
immediatly without stalling.  We could also handle this with a new
create flag to ask the driver to create a syncobj that is already
signaled but the IOCTL seemed a bit cleaner and more generic.

v2:
 - Take an array of sync objects (Dave Airlie)
v3:
 - Throw -EINVAL if pad != 0

Signed-off-by: default avatarJason Ekstrand <jason@jlekstrand.net>
Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
parent aa4035d2

drivers/gpu/drm/drm_internal.h

+2 −0
Original line number Diff line number Diff line
@@ -171,3 +171,5 @@ int drm_syncobj_wait_ioctl(struct drm_device *dev, void *data, 
			   struct drm_file *file_private);

int drm_syncobj_reset_ioctl(struct drm_device *dev, void *data,

			    struct drm_file *file_private);

int drm_syncobj_signal_ioctl(struct drm_device *dev, void *data,

			     struct drm_file *file_private);

drivers/gpu/drm/drm_ioctl.c

+2 −0
Original line number Diff line number Diff line
@@ -661,6 +661,8 @@ static const struct drm_ioctl_desc drm_ioctls[] = { 
		      DRM_UNLOCKED|DRM_RENDER_ALLOW),

	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_RESET, drm_syncobj_reset_ioctl,

		      DRM_UNLOCKED|DRM_RENDER_ALLOW),

	DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_SIGNAL, drm_syncobj_signal_ioctl,

		      DRM_UNLOCKED|DRM_RENDER_ALLOW),

};



#define DRM_CORE_IOCTL_COUNT	ARRAY_SIZE( drm_ioctls )

drivers/gpu/drm/drm_syncobj.c

+36 −0
Original line number Diff line number Diff line
@@ -918,3 +918,39 @@ drm_syncobj_reset_ioctl(struct drm_device *dev, void *data, 


	return 0;

}



int

drm_syncobj_signal_ioctl(struct drm_device *dev, void *data,

			 struct drm_file *file_private)

{

	struct drm_syncobj_array *args = data;

	struct drm_syncobj **syncobjs;

	uint32_t i;

	int ret;



	if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))

		return -ENODEV;



	if (args->pad != 0)

		return -EINVAL;



	if (args->count_handles == 0)

		return -EINVAL;



	ret = drm_syncobj_array_find(file_private,

				     u64_to_user_ptr(args->handles),

				     args->count_handles,

				     &syncobjs);

	if (ret < 0)

		return ret;



	for (i = 0; i < args->count_handles; i++) {

		ret = drm_syncobj_assign_null_handle(syncobjs[i]);

		if (ret < 0)

			break;

	}



	drm_syncobj_array_free(syncobjs, args->count_handles);



	return ret;

}

include/uapi/drm/drm.h

+1 −0
Original line number Diff line number Diff line
@@ -861,6 +861,7 @@ extern "C" { 
#define DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE	DRM_IOWR(0xC2, struct drm_syncobj_handle)

#define DRM_IOCTL_SYNCOBJ_WAIT		DRM_IOWR(0xC3, struct drm_syncobj_wait)

#define DRM_IOCTL_SYNCOBJ_RESET		DRM_IOWR(0xC4, struct drm_syncobj_array)

#define DRM_IOCTL_SYNCOBJ_SIGNAL	DRM_IOWR(0xC5, struct drm_syncobj_array)



/**

 * Device specific ioctls should only be in their respective headers

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