.

bigfile/_bigfile.c

@@ -908,7 +908,9 @@ out:
 static void*
 pybigfile_mmap_setup_read(VMA *vma, BigFile *file0, blk_t blk, size_t blklen)
 {
-    BUG();  // XXX
+    PyBigFile *file = container_of(file0, PyBigFile, file);
+    ASSERT(file->blkmmap_ops != NULL);
+    return file->blkmmap_ops->mmap_setup_read(vma, file0, blk, blklen);
 }
 
 static int