1 /* 2 * This file is subject to the terms and conditions of the GNU General Public 3 * License. See the file "COPYING" in the main directory of this archive 4 * for more details. 5 * 6 * Copyright (C) 2003 by Ralf Baechle 7 */ 8 #include <linux/config.h> 9 #include <linux/init.h> 10 #include <linux/mm.h> 11 #include <linux/bootmem.h> 12 #include <linux/highmem.h> 13 #include <asm/pgtable.h> 14 15 void pgd_init(unsigned long page) 16 { 17 unsigned long *p = (unsigned long *) page; 18 int i; 19 20 for (i = 0; i < USER_PTRS_PER_PGD; i+=8) { 21 p[i + 0] = (unsigned long) invalid_pte_table; 22 p[i + 1] = (unsigned long) invalid_pte_table; 23 p[i + 2] = (unsigned long) invalid_pte_table; 24 p[i + 3] = (unsigned long) invalid_pte_table; 25 p[i + 4] = (unsigned long) invalid_pte_table; 26 p[i + 5] = (unsigned long) invalid_pte_table; 27 p[i + 6] = (unsigned long) invalid_pte_table; 28 p[i + 7] = (unsigned long) invalid_pte_table; 29 } 30 } 31 32 #ifdef CONFIG_HIGHMEM 33 static void __init fixrange_init (unsigned long start, unsigned long end, 34 pgd_t *pgd_base) 35 { 36 pgd_t *pgd; 37 pmd_t *pmd; 38 pte_t *pte; 39 int i, j; 40 unsigned long vaddr; 41 42 vaddr = start; 43 i = __pgd_offset(vaddr); 44 j = __pmd_offset(vaddr); 45 pgd = pgd_base + i; 46 47 for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) { 48 pmd = (pmd_t *)pgd; 49 for (; (j < PTRS_PER_PMD) && (vaddr != end); pmd++, j++) { 50 if (pmd_none(*pmd)) { 51 pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE); 52 set_pmd(pmd, __pmd((unsigned long)pte)); 53 if (pte != pte_offset_kernel(pmd, 0)) 54 BUG(); 55 } 56 vaddr += PMD_SIZE; 57 } 58 j = 0; 59 } 60 } 61 #endif 62 63 void __init pagetable_init(void) 64 { 65 #ifdef CONFIG_HIGHMEM 66 unsigned long vaddr; 67 pgd_t *pgd, *pgd_base; 68 pmd_t *pmd; 69 pte_t *pte; 70 #endif 71 72 /* Initialize the entire pgd. */ 73 pgd_init((unsigned long)swapper_pg_dir); 74 pgd_init((unsigned long)swapper_pg_dir 75 + sizeof(pgd_t) * USER_PTRS_PER_PGD); 76 77 #ifdef CONFIG_HIGHMEM 78 pgd_base = swapper_pg_dir; 79 80 /* 81 * Fixed mappings: 82 */ 83 vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK; 84 fixrange_init(vaddr, 0, pgd_base); 85 86 /* 87 * Permanent kmaps: 88 */ 89 vaddr = PKMAP_BASE; 90 fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base); 91 92 pgd = swapper_pg_dir + __pgd_offset(vaddr); 93 pmd = pmd_offset(pgd, vaddr); 94 pte = pte_offset_kernel(pmd, vaddr); 95 pkmap_page_table = pte; 96 #endif 97 } 98