patch-2.4.3 linux/arch/i386/mm/init.c
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- Lines: 158
- Date:
Mon Mar 26 11:01:56 2001
- Orig file:
v2.4.2/linux/arch/i386/mm/init.c
- Orig date:
Sat Feb 3 19:51:22 2001
diff -u --recursive --new-file v2.4.2/linux/arch/i386/mm/init.c linux/arch/i386/mm/init.c
@@ -40,132 +40,23 @@
static unsigned long totalram_pages;
static unsigned long totalhigh_pages;
-/*
- * BAD_PAGE is the page that is used for page faults when linux
- * is out-of-memory. Older versions of linux just did a
- * do_exit(), but using this instead means there is less risk
- * for a process dying in kernel mode, possibly leaving an inode
- * unused etc..
- *
- * BAD_PAGETABLE is the accompanying page-table: it is initialized
- * to point to BAD_PAGE entries.
- *
- * ZERO_PAGE is a special page that is used for zero-initialized
- * data and COW.
- */
-
-/*
- * These are allocated in head.S so that we get proper page alignment.
- * If you change the size of these then change head.S as well.
- */
-extern char empty_bad_page[PAGE_SIZE];
-#if CONFIG_X86_PAE
-extern pmd_t empty_bad_pmd_table[PTRS_PER_PMD];
-#endif
-extern pte_t empty_bad_pte_table[PTRS_PER_PTE];
-
-/*
- * We init them before every return and make them writable-shared.
- * This guarantees we get out of the kernel in some more or less sane
- * way.
- */
-#if CONFIG_X86_PAE
-static pmd_t * get_bad_pmd_table(void)
-{
- pmd_t v;
- int i;
-
- set_pmd(&v, __pmd(_PAGE_TABLE + __pa(empty_bad_pte_table)));
-
- for (i = 0; i < PAGE_SIZE/sizeof(pmd_t); i++)
- empty_bad_pmd_table[i] = v;
-
- return empty_bad_pmd_table;
-}
-#endif
-
-static pte_t * get_bad_pte_table(void)
-{
- pte_t v;
- int i;
-
- v = pte_mkdirty(mk_pte_phys(__pa(empty_bad_page), PAGE_SHARED));
-
- for (i = 0; i < PAGE_SIZE/sizeof(pte_t); i++)
- empty_bad_pte_table[i] = v;
-
- return empty_bad_pte_table;
-}
-
-
-
-void __handle_bad_pmd(pmd_t *pmd)
-{
- pmd_ERROR(*pmd);
- set_pmd(pmd, __pmd(_PAGE_TABLE + __pa(get_bad_pte_table())));
-}
-
-void __handle_bad_pmd_kernel(pmd_t *pmd)
-{
- pmd_ERROR(*pmd);
- set_pmd(pmd, __pmd(_KERNPG_TABLE + __pa(get_bad_pte_table())));
-}
-
-pte_t *get_pte_kernel_slow(pmd_t *pmd, unsigned long offset)
-{
- pte_t *pte;
-
- pte = (pte_t *) __get_free_page(GFP_KERNEL);
- if (pmd_none(*pmd)) {
- if (pte) {
- clear_page(pte);
- set_pmd(pmd, __pmd(_KERNPG_TABLE + __pa(pte)));
- return pte + offset;
- }
- set_pmd(pmd, __pmd(_KERNPG_TABLE + __pa(get_bad_pte_table())));
- return NULL;
- }
- free_page((unsigned long)pte);
- if (pmd_bad(*pmd)) {
- __handle_bad_pmd_kernel(pmd);
- return NULL;
- }
- return (pte_t *) pmd_page(*pmd) + offset;
-}
-
-pte_t *get_pte_slow(pmd_t *pmd, unsigned long offset)
-{
- unsigned long pte;
-
- pte = (unsigned long) __get_free_page(GFP_KERNEL);
- if (pmd_none(*pmd)) {
- if (pte) {
- clear_page((void *)pte);
- set_pmd(pmd, __pmd(_PAGE_TABLE + __pa(pte)));
- return (pte_t *)pte + offset;
- }
- set_pmd(pmd, __pmd(_PAGE_TABLE + __pa(get_bad_pte_table())));
- return NULL;
- }
- free_page(pte);
- if (pmd_bad(*pmd)) {
- __handle_bad_pmd(pmd);
- return NULL;
- }
- return (pte_t *) pmd_page(*pmd) + offset;
-}
-
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++;
+ if (pgd_quicklist) {
+ free_pgd_slow(get_pgd_fast());
+ freed++;
+ }
+ if (pmd_quicklist) {
+ pmd_free_slow(pmd_alloc_one_fast(NULL, 0));
+ freed++;
+ }
+ if (pte_quicklist) {
+ pte_free_slow(pte_alloc_one_fast(NULL, 0));
+ freed++;
+ }
} while(pgtable_cache_size > low);
}
return freed;
@@ -327,10 +218,8 @@
pgd_base = swapper_pg_dir;
#if CONFIG_X86_PAE
- for (i = 0; i < PTRS_PER_PGD; i++) {
- pgd = pgd_base + i;
- __pgd_clear(pgd);
- }
+ for (i = 0; i < PTRS_PER_PGD; i++)
+ set_pgd(pgd_base + i, __pgd(1 + __pa(empty_zero_page)));
#endif
i = __pgd_offset(PAGE_OFFSET);
pgd = pgd_base + i;
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