diff --git a/include/ion/ion.h b/include/ion/ion.h
index 018c0a1..47a4030 100644
--- a/include/ion/ion.h
+++ b/include/ion/ion.h
@@ -28,15 +28,15 @@
 int ion_open();
 int ion_close(int fd);
 int ion_alloc(int fd, size_t len, size_t align, unsigned int heap_mask,
-	      unsigned int flags, struct ion_handle **handle);
+	      unsigned int flags, ion_user_handle_t *handle);
 int ion_alloc_fd(int fd, size_t len, size_t align, unsigned int heap_mask,
 		 unsigned int flags, int *handle_fd);
 int ion_sync_fd(int fd, int handle_fd);
-int ion_free(int fd, struct ion_handle *handle);
-int ion_map(int fd, struct ion_handle *handle, size_t length, int prot,
+int ion_free(int fd, ion_user_handle_t handle);
+int ion_map(int fd, ion_user_handle_t handle, size_t length, int prot,
             int flags, off_t offset, unsigned char **ptr, int *map_fd);
-int ion_share(int fd, struct ion_handle *handle, int *share_fd);
-int ion_import(int fd, int share_fd, struct ion_handle **handle);
+int ion_share(int fd, ion_user_handle_t handle, int *share_fd);
+int ion_import(int fd, int share_fd, ion_user_handle_t *handle);
 
 __END_DECLS