drm/amdgpu: use a sync object for VMID fences v2

v2: rebase & cleanup

This way we can store more than one fence as user for each VMID.

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com> (v1)
Reviewed-by: Chunming Zhou <david1.zhou@amd.com> (v1)
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu.h

@@ -588,6 +588,9 @@ int amdgpu_sync_resv(struct amdgpu_device *adev,
 		     struct amdgpu_sync *sync,
 		     struct reservation_object *resv,
 		     void *owner);
+bool amdgpu_sync_is_idle(struct amdgpu_sync *sync);
+int amdgpu_sync_cycle_fences(struct amdgpu_sync *dst, struct amdgpu_sync *src,
+			     struct fence *fence);
 struct fence *amdgpu_sync_get_fence(struct amdgpu_sync *sync);
 int amdgpu_sync_wait(struct amdgpu_sync *sync);
 void amdgpu_sync_free(struct amdgpu_sync *sync);
@@ -875,7 +878,8 @@ struct amdgpu_vm {
 
 struct amdgpu_vm_id {
 	struct list_head	list;
-	struct fence		*active;
+	struct fence		*first;
+	struct amdgpu_sync	active;
 	atomic_long_t		owner;
 
 	uint64_t		pd_gpu_addr;