- start = res->start += offset;
- end = res->end += offset;
-
- /* Need to allow IO access to pages that are in the
- ISA range */
- if (start < MAX_ISA_PORT) {
- if (end > MAX_ISA_PORT)
- end = MAX_ISA_PORT;
-
- start >>= PAGE_SHIFT;
- end >>= PAGE_SHIFT;
-
- /* get the range of pages for the map */
- mask = ((1 << (end+1)) - 1) ^ ((1 << start) - 1);
- io_page_mask |= mask;
- }