MIPS: Limit fixrange_init() to the FIXMAP region

fixrange_init() allocates page tables for all addresses higher than
FIXADDR_TOP.  On processors that override the default FIXADDR_TOP
address of 0xfffe_0000, this can consume up to 4 pages (1 page per 4MB)
for pgd's that are never used.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/1980/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Kevin Cernekee 2011-01-05 23:31:30 -08:00 committed by Ralf Baechle
parent 273f2d7e64
commit 464fd83e84
3 changed files with 5 additions and 5 deletions

View file

@ -277,11 +277,11 @@ void __init fixrange_init(unsigned long start, unsigned long end,
k = __pmd_offset(vaddr);
pgd = pgd_base + i;
for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
pud = (pud_t *)pgd;
for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
for ( ; (j < PTRS_PER_PUD) && (vaddr < end); pud++, j++) {
pmd = (pmd_t *)pud;
for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
for (; (k < PTRS_PER_PMD) && (vaddr < end); pmd++, k++) {
if (pmd_none(*pmd)) {
pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
set_pmd(pmd, __pmd((unsigned long)pte));

View file

@ -52,7 +52,7 @@ void __init pagetable_init(void)
* Fixed mappings:
*/
vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
fixrange_init(vaddr, 0, pgd_base);
fixrange_init(vaddr, vaddr + FIXADDR_SIZE, pgd_base);
#ifdef CONFIG_HIGHMEM
/*

View file

@ -76,5 +76,5 @@ void __init pagetable_init(void)
* Fixed mappings:
*/
vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
fixrange_init(vaddr, 0, pgd_base);
fixrange_init(vaddr, vaddr + FIXADDR_SIZE, pgd_base);
}