linux/arch/mips/mm/pgtable-32.c

98 lines
2.2 KiB
C
Raw Normal View History

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2003 by Ralf Baechle
*/
#include <linux/config.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/bootmem.h>
#include <linux/highmem.h>
#include <asm/pgtable.h>
void pgd_init(unsigned long page)
{
unsigned long *p = (unsigned long *) page;
int i;
for (i = 0; i < USER_PTRS_PER_PGD; i+=8) {
p[i + 0] = (unsigned long) invalid_pte_table;
p[i + 1] = (unsigned long) invalid_pte_table;
p[i + 2] = (unsigned long) invalid_pte_table;
p[i + 3] = (unsigned long) invalid_pte_table;
p[i + 4] = (unsigned long) invalid_pte_table;
p[i + 5] = (unsigned long) invalid_pte_table;
p[i + 6] = (unsigned long) invalid_pte_table;
p[i + 7] = (unsigned long) invalid_pte_table;
}
}
#ifdef CONFIG_HIGHMEM
static void __init fixrange_init (unsigned long start, unsigned long end,
pgd_t *pgd_base)
{
pgd_t *pgd;
pmd_t *pmd;
pte_t *pte;
int i, j;
unsigned long vaddr;
vaddr = start;
i = __pgd_offset(vaddr);
j = __pmd_offset(vaddr);
pgd = pgd_base + i;
for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
pmd = (pmd_t *)pgd;
for (; (j < PTRS_PER_PMD) && (vaddr != end); pmd++, j++) {
if (pmd_none(*pmd)) {
pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
set_pmd(pmd, __pmd((unsigned long)pte));
if (pte != pte_offset_kernel(pmd, 0))
BUG();
}
vaddr += PMD_SIZE;
}
j = 0;
}
}
#endif
void __init pagetable_init(void)
{
#ifdef CONFIG_HIGHMEM
unsigned long vaddr;
pgd_t *pgd, *pgd_base;
pmd_t *pmd;
pte_t *pte;
#endif
/* Initialize the entire pgd. */
pgd_init((unsigned long)swapper_pg_dir);
pgd_init((unsigned long)swapper_pg_dir
+ sizeof(pgd_t) * USER_PTRS_PER_PGD);
#ifdef CONFIG_HIGHMEM
pgd_base = swapper_pg_dir;
/*
* Fixed mappings:
*/
vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
fixrange_init(vaddr, 0, pgd_base);
/*
* Permanent kmaps:
*/
vaddr = PKMAP_BASE;
fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base);
pgd = swapper_pg_dir + __pgd_offset(vaddr);
pmd = pmd_offset(pgd, vaddr);
pte = pte_offset_kernel(pmd, vaddr);
pkmap_page_table = pte;
#endif
}