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x86: allocate and initialize unshared pmds 

If SHARED_KERNEL_PMD is false, then we need to allocate and initialize
the kernel pmd.  We can easily piggy-back this onto the existing pmd
prepopulation code.

Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Jeremy Fitzhardinge 2008-01-30 13:33:40 +01:00 committed by Ingo Molnar
parent 8fe3deef01
commit 508bebbb1f
1 changed files with 11 additions and 3 deletions
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14
arch/x86/mm/pgtable_32.c
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@ -305,7 +305,7 @@ static void pgd_mop_up_pmds(pgd_t *pgdp)
{
int i;
for(i = 0; i < USER_PTRS_PER_PGD; i++) {
for(i = 0; i < UNSHARED_PTRS_PER_PGD; i++) {
pgd_t pgd = pgdp[i];
if (pgd_val(pgd) != 0) {
@ -325,6 +325,10 @@ static void pgd_mop_up_pmds(pgd_t *pgdp)
* processor notices the update. Since this is expensive, and
* all 4 top-level entries are used almost immediately in a
* new process's life, we just pre-populate them here.
*
* Also, if we're in a paravirt environment where the kernel pmd is
* not shared between pagetables (!SHARED_KERNEL_PMDS), we allocate
* and initialize the kernel pmds here.
*/
static int pgd_prepopulate_pmd(struct mm_struct *mm, pgd_t *pgd)
{
@ -333,7 +337,8 @@ static int pgd_prepopulate_pmd(struct mm_struct *mm, pgd_t *pgd)
int i;
pud = pud_offset(pgd, 0);
for (addr = i = 0; i < USER_PTRS_PER_PGD; i++, pud++, addr += PUD_SIZE) {
for (addr = i = 0; i < UNSHARED_PTRS_PER_PGD;
i++, pud++, addr += PUD_SIZE) {
pmd_t *pmd = pmd_alloc_one(mm, addr);
if (!pmd) {
@ -341,6 +346,10 @@ static int pgd_prepopulate_pmd(struct mm_struct *mm, pgd_t *pgd)
return 0;
}
if (i >= USER_PTRS_PER_PGD)
memcpy(pmd, (pmd_t *)pgd_page_vaddr(swapper_pg_dir[i]),
sizeof(pmd_t) * PTRS_PER_PMD);
pud_populate(mm, pud, pmd);
}
@ -444,4 +453,3 @@ void check_pgt_cache(void)
{
quicklist_trim(0, pgd_dtor, 25, 16);
}