>From Al Viro - add three-level page table support to fixrange_init.
Signed-off-by: Jeff Dike <[email protected]>
Index: linux-2.6.12-rc/arch/um/kernel/mem.c
===================================================================
--- linux-2.6.12-rc.orig/arch/um/kernel/mem.c 2005-05-17 18:02:25.000000000 -0400
+++ linux-2.6.12-rc/arch/um/kernel/mem.c 2005-05-17 18:21:32.000000000 -0400
@@ -100,12 +100,37 @@ void mem_init(void)
#endif
}
+/*
+ * Create a page table and place a pointer to it in a middle page
+ * directory entry.
+ */
+static void __init one_page_table_init(pmd_t *pmd)
+{
+ if (pmd_none(*pmd)) {
+ pte_t *pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
+ set_pmd(pmd, __pmd(_KERNPG_TABLE +
+ (unsigned long) __pa(pte)));
+ if (pte != pte_offset_kernel(pmd, 0))
+ BUG();
+ }
+}
+
+static void __init one_md_table_init(pud_t *pud)
+{
+#ifdef CONFIG_3_LEVEL_PGTABLES
+ pmd_t *pmd_table = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE);
+ set_pud(pud, __pud(_KERNPG_TABLE + (unsigned long) __pa(pmd_table)));
+ if (pmd_table != pmd_offset(pud, 0))
+ BUG();
+#endif
+}
+
static void __init fixrange_init(unsigned long start, unsigned long end,
pgd_t *pgd_base)
{
pgd_t *pgd;
+ pud_t *pud;
pmd_t *pmd;
- pte_t *pte;
int i, j;
unsigned long vaddr;
@@ -115,15 +140,12 @@ static void __init fixrange_init(unsigne
pgd = pgd_base + i;
for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
- pmd = (pmd_t *)pgd;
+ pud = pud_offset(pgd, vaddr);
+ if (pud_none(*pud))
+ one_md_table_init(pud);
+ pmd = pmd_offset(pud, vaddr);
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(_KERNPG_TABLE +
- (unsigned long) __pa(pte)));
- if (pte != pte_offset_kernel(pmd, 0))
- BUG();
- }
+ one_page_table_init(pmd);
vaddr += PMD_SIZE;
}
j = 0;