return NULL;
 }
 
+/* free a coherent mapping */
+static void
+gart_free_coherent(struct device *dev, size_t size, void *vaddr,
+                  dma_addr_t dma_addr)
+{
+       gart_unmap_single(dev, dma_addr, size, DMA_BIDIRECTIONAL);
+       free_pages((unsigned long)vaddr, get_order(size));
+}
+
 static int no_agp;
 
 static __init unsigned long check_iommu_size(unsigned long aper, u64 aper_size)
        .map_sg                         = gart_map_sg,
        .unmap_sg                       = gart_unmap_sg,
        .alloc_coherent                 = gart_alloc_coherent,
+       .free_coherent                  = gart_free_coherent,
 };
 
 void gart_iommu_shutdown(void)