static pmd_t *__init get_pmd(pgd_t pgtables[], unsigned long va)
{
pud_t *pud = pud_offset(&pgtables[pgd_index(va)], va);
if (pud_none(*pud))
assign_pmd(pud, alloc_pmd());
return pmd_offset(pud, va);
}
/*
* paging_init() sets up the page tables - note that all of lowmem is
* already mapped by head.S.
*/
void __init paging_init(void)
{
#ifdef __tilegx__
pud_t *pud;
#endif
pgd_t *pgd_base = swapper_pg_dir;
kernel_physical_mapping_init(pgd_base);
/* Fixed mappings, only the page table structure has to be created. */
page_table_range_init(fix_to_virt(__end_of_fixed_addresses - 1),
FIXADDR_TOP, pgd_base);
#ifdef CONFIG_HIGHMEM
permanent_kmaps_init(pgd_base);
#endif
#ifdef __tilegx__
/*
* Since GX allocates just one pmd_t array worth of vmalloc space,
* we go ahead and allocate it statically here, then share it
* globally. As a result we don't have to worry about any task
* changing init_mm once we get up and running, and there's no
* need for e.g. vmalloc_sync_all().
*/
BUILD_BUG_ON(pgd_index(VMALLOC_START) != pgd_index(VMALLOC_END - 1));
pud = pud_offset(pgd_base + pgd_index(VMALLOC_START), VMALLOC_START);
assign_pmd(pud, alloc_pmd());
#endif
}