drm/radeon: stop using TTMs fault callback

We already implemented the fault handler ourself,
just open code what is necessary here.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/392322/

drivers/gpu/drm/radeon/radeon_object.c

@@ -775,7 +775,7 @@ void radeon_bo_move_notify(struct ttm_buffer_object *bo,
 	radeon_update_memory_usage(rbo, new_mem->mem_type, 1);
 }
 
-int radeon_bo_fault_reserve_notify(struct ttm_buffer_object *bo)
+vm_fault_t radeon_bo_fault_reserve_notify(struct ttm_buffer_object *bo)
 {
 	struct ttm_operation_ctx ctx = { false, false };
 	struct radeon_device *rdev;
@@ -798,7 +798,7 @@ int radeon_bo_fault_reserve_notify(struct ttm_buffer_object *bo)
 
 	/* Can't move a pinned BO to visible VRAM */
 	if (rbo->tbo.pin_count > 0)
-		return -EINVAL;
+		return VM_FAULT_SIGBUS;
 
 	/* hurrah the memory is not visible ! */
 	radeon_ttm_placement_from_domain(rbo, RADEON_GEM_DOMAIN_VRAM);
@@ -812,16 +812,20 @@ int radeon_bo_fault_reserve_notify(struct ttm_buffer_object *bo)
 	r = ttm_bo_validate(bo, &rbo->placement, &ctx);
 	if (unlikely(r == -ENOMEM)) {
 		radeon_ttm_placement_from_domain(rbo, RADEON_GEM_DOMAIN_GTT);
-		return ttm_bo_validate(bo, &rbo->placement, &ctx);
-	} else if (unlikely(r != 0)) {
-		return r;
+		r = ttm_bo_validate(bo, &rbo->placement, &ctx);
+	} else if (likely(!r)) {
+		offset = bo->mem.start << PAGE_SHIFT;
+		/* this should never happen */
+		if ((offset + size) > rdev->mc.visible_vram_size)
+			return VM_FAULT_SIGBUS;
 	}
 
-	offset = bo->mem.start << PAGE_SHIFT;
-	/* this should never happen */
-	if ((offset + size) > rdev->mc.visible_vram_size)
-		return -EINVAL;
+	if (unlikely(r == -EBUSY || r == -ERESTARTSYS))
+		return VM_FAULT_NOPAGE;
+	else if (unlikely(r))
+		return VM_FAULT_SIGBUS;
 
+	ttm_bo_move_to_lru_tail_unlocked(bo);
 	return 0;
 }
 

drivers/gpu/drm/radeon/radeon_object.h

@@ -163,7 +163,7 @@ extern int radeon_bo_check_tiling(struct radeon_bo *bo, bool has_moved,
 extern void radeon_bo_move_notify(struct ttm_buffer_object *bo,
 				  bool evict,
 				  struct ttm_resource *new_mem);
-extern int radeon_bo_fault_reserve_notify(struct ttm_buffer_object *bo);
+extern vm_fault_t radeon_bo_fault_reserve_notify(struct ttm_buffer_object *bo);
 extern int radeon_bo_get_surface_reg(struct radeon_bo *bo);
 extern void radeon_bo_fence(struct radeon_bo *bo, struct radeon_fence *fence,
 			    bool shared);

drivers/gpu/drm/radeon/radeon_ttm.c

@@ -803,7 +803,6 @@ static struct ttm_bo_driver radeon_bo_driver = {
 	.move = &radeon_bo_move,
 	.verify_access = &radeon_verify_access,
 	.move_notify = &radeon_bo_move_notify,
-	.fault_reserve_notify = &radeon_bo_fault_reserve_notify,
 	.io_mem_reserve = &radeon_ttm_io_mem_reserve,
 };
 
@@ -904,17 +903,29 @@ void radeon_ttm_set_active_vram_size(struct radeon_device *rdev, u64 size)
 
 static vm_fault_t radeon_ttm_fault(struct vm_fault *vmf)
 {
-	struct ttm_buffer_object *bo;
-	struct radeon_device *rdev;
+	struct ttm_buffer_object *bo = vmf->vma->vm_private_data;
+	struct radeon_device *rdev = radeon_get_rdev(bo->bdev);
 	vm_fault_t ret;
 
-	bo = (struct ttm_buffer_object *)vmf->vma->vm_private_data;
-	if (bo == NULL)
-		return VM_FAULT_NOPAGE;
-
-	rdev = radeon_get_rdev(bo->bdev);
 	down_read(&rdev->pm.mclk_lock);
-	ret = ttm_bo_vm_fault(vmf);
+
+	ret = ttm_bo_vm_reserve(bo, vmf);
+	if (ret)
+		goto unlock_mclk;
+
+	ret = radeon_bo_fault_reserve_notify(bo);
+	if (ret)
+		goto unlock_resv;
+
+	ret = ttm_bo_vm_fault_reserved(vmf, vmf->vma->vm_page_prot,
+				       TTM_BO_VM_NUM_PREFAULT, 1);
+	if (ret == VM_FAULT_RETRY && !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT))
+		goto unlock_mclk;
+
+unlock_resv:
+	dma_resv_unlock(bo->base.resv);
+
+unlock_mclk:
 	up_read(&rdev->pm.mclk_lock);
 	return ret;
 }