XENSHM_MAX_PAGES_PER_REQUEST
gnttab_unmap_grant_ref_t unop[XENSHM_MAX_PAGES_PER_REQUEST];
gnttab_unmap_grant_ref_t op[XENSHM_MAX_PAGES_PER_REQUEST];
if (nentries > XENSHM_MAX_PAGES_PER_REQUEST) {
gnttab_map_grant_ref_t op[XENSHM_MAX_PAGES_PER_REQUEST];
if (nentries > XENSHM_MAX_PAGES_PER_REQUEST) {
CTASSERT(XENSHM_MAX_PAGES_PER_REQUEST >= VBD_MAX_INDIRECT_SEGMENTS);