void check_pgt_cache(void)
{
preempt_disable();
if (pgtable_cache_size > PGT_CACHE_HIGH) {
do {
#ifdef CONFIG_SMP
if (pgd_quicklist)
free_pgd_slow(get_pgd_fast());
#endif
if (pte_quicklist[0])
free_pte_slow(pte_alloc_one_fast(NULL, 0));
if (pte_quicklist[1])
free_pte_slow(pte_alloc_one_fast(NULL, 1 << (PAGE_SHIFT + 10)));
} while (pgtable_cache_size > PGT_CACHE_LOW);
}
#ifndef CONFIG_SMP
if (pgd_cache_size > PGT_CACHE_HIGH / 4) {
struct page *page, *page2;
for (page2 = NULL, page = (struct page *)pgd_quicklist; page;) {
if ((unsigned long)page->lru.prev == 3) {
if (page2)
page2->lru.next = page->lru.next;
else
pgd_quicklist = (void *) page->lru.next;
pgd_cache_size -= 2;
__free_page(page);
if (page2)
page = (struct page *)page2->lru.next;
else
page = (struct page *)pgd_quicklist;
if (pgd_cache_size <= PGT_CACHE_LOW / 4)
break;
continue;
}
page2 = page;
page = (struct page *)page->lru.next;
}
}
#endif
preempt_enable();
}
int do_check_pgt_cache(int low, int high)
{
int freed = 0;
if(pgtable_cache_size > high) {
do {
if(pgd_quicklist)
free_pgd_slow(get_pgd_fast()), freed++;
if(pmd_quicklist)
free_pmd_slow(get_pmd_fast()), freed++;
if(pte_quicklist)
free_pte_slow(get_pte_fast()), freed++;
} while(pgtable_cache_size > low);
}
return freed;
}
pte_t *get_pte_slow(pmd_t *pmd, unsigned long offset)
{
pte_t *pte;
pte = (pte_t *)alloc_pte_table(PTRS_PER_PTE * sizeof(pte_t), GFP_KERNEL);
if (pmd_none(*pmd)) {
if (pte) {
memzero(pte, PTRS_PER_PTE * sizeof(pte_t));
set_pmd(pmd, mk_user_pmd(pte));
return pte + offset;
}
set_pmd(pmd, mk_user_pmd(get_bad_pte_table()));
return NULL;
}
free_pte_slow(pte);
if (pmd_bad(*pmd)) {
__handle_bad_pmd(pmd);
return NULL;
}
return (pte_t *) pmd_page(*pmd) + offset;
}
