+ unsigned int offset_r = (cd->offset - tmp) << 2;
+
+ /* update pointer to offset location.
+ * This is a 64bit quantity, so we need to
+ * deal with 3 cases:
+ * - entirely in first page
+ * - entirely in second page
+ * - 4 bytes in each page
+ */
+ if (offset_r + 8 <= len1) {
+ cd->offset = p + (cd->offset - tmp);
+ } else if (offset_r >= len1) {
+ cd->offset -= len1 >> 2;
+ } else {
+ /* sitting on the fence */
+ BUG_ON(offset_r != len1 - 4);
+ cd->offset = p + (cd->offset - tmp);
+ cd->offset1 = tmp;
+ }
+