blob: 943515f0ef8709c113f8a063ad17fd741820bc4c [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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) 1994, 95, 96, 97, 98, 99, 2000, 2003 Ralf Baechle
7 * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
8 */
9#ifndef _ASM_PGTABLE_64_H
10#define _ASM_PGTABLE_64_H
11
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <linux/linkage.h>
13
14#include <asm/addrspace.h>
15#include <asm/page.h>
16#include <asm/cachectl.h>
Atsushi Nemoto656be922006-10-26 00:08:31 +090017#include <asm/fixmap.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070018
Ralf Baechlec6e8b582005-02-10 12:19:59 +000019#include <asm-generic/pgtable-nopud.h>
20
Linus Torvalds1da177e2005-04-16 15:20:36 -070021/*
22 * Each address space has 2 4K pages as its page directory, giving 1024
23 * (== PTRS_PER_PGD) 8 byte pointers to pmd tables. Each pmd table is a
Ralf Baechlec6e8b582005-02-10 12:19:59 +000024 * single 4K page, giving 512 (== PTRS_PER_PMD) 8 byte pointers to page
25 * tables. Each page table is also a single 4K page, giving 512 (==
26 * PTRS_PER_PTE) 8 byte ptes. Each pud entry is initialized to point to
27 * invalid_pmd_table, each pmd entry is initialized to point to
Linus Torvalds1da177e2005-04-16 15:20:36 -070028 * invalid_pte_table, each pte is initialized to 0. When memory is low,
29 * and a pmd table or a page table allocation fails, empty_bad_pmd_table
30 * and empty_bad_page_table is returned back to higher layer code, so
31 * that the failure is recognized later on. Linux does not seem to
32 * handle these failures very well though. The empty_bad_page_table has
33 * invalid pte entries in it, to force page faults.
34 *
35 * Kernel mappings: kernel mappings are held in the swapper_pg_table.
36 * The layout is identical to userspace except it's indexed with the
37 * fault address - VMALLOC_START.
38 */
39
40/* PMD_SHIFT determines the size of the area a second-level page table can map */
Ralf Baechlec6e8b582005-02-10 12:19:59 +000041#define PMD_SHIFT (PAGE_SHIFT + (PAGE_SHIFT + PTE_ORDER - 3))
Linus Torvalds1da177e2005-04-16 15:20:36 -070042#define PMD_SIZE (1UL << PMD_SHIFT)
43#define PMD_MASK (~(PMD_SIZE-1))
44
45/* PGDIR_SHIFT determines what a third-level page table entry can map */
Ralf Baechlec6e8b582005-02-10 12:19:59 +000046#define PGDIR_SHIFT (PMD_SHIFT + (PAGE_SHIFT + PMD_ORDER - 3))
Linus Torvalds1da177e2005-04-16 15:20:36 -070047#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
48#define PGDIR_MASK (~(PGDIR_SIZE-1))
49
50/*
Ralf Baechlec6e8b582005-02-10 12:19:59 +000051 * For 4kB page size we use a 3 level page tree and an 8kB pud, which
Linus Torvalds1da177e2005-04-16 15:20:36 -070052 * permits us mapping 40 bits of virtual address space.
53 *
54 * We used to implement 41 bits by having an order 1 pmd level but that seemed
55 * rather pointless.
56 *
57 * For 8kB page size we use a 3 level page tree which permits a total of
58 * 8TB of address space. Alternatively a 33-bit / 8GB organization using
59 * two levels would be easy to implement.
60 *
61 * For 16kB page size we use a 2 level page tree which permits a total of
Thiemo Seuferf29244a2005-02-21 11:11:32 +000062 * 36 bits of virtual address space. We could add a third level but it seems
Linus Torvalds1da177e2005-04-16 15:20:36 -070063 * like at the moment there's no need for this.
64 *
65 * For 64kB page size we use a 2 level page table tree for a total of 42 bits
66 * of virtual address space.
67 */
68#ifdef CONFIG_PAGE_SIZE_4KB
69#define PGD_ORDER 1
Ralf Baechlec6e8b582005-02-10 12:19:59 +000070#define PUD_ORDER aieeee_attempt_to_allocate_pud
Linus Torvalds1da177e2005-04-16 15:20:36 -070071#define PMD_ORDER 0
72#define PTE_ORDER 0
73#endif
74#ifdef CONFIG_PAGE_SIZE_8KB
75#define PGD_ORDER 0
Ralf Baechlec6e8b582005-02-10 12:19:59 +000076#define PUD_ORDER aieeee_attempt_to_allocate_pud
Linus Torvalds1da177e2005-04-16 15:20:36 -070077#define PMD_ORDER 0
78#define PTE_ORDER 0
79#endif
80#ifdef CONFIG_PAGE_SIZE_16KB
81#define PGD_ORDER 0
Ralf Baechlec6e8b582005-02-10 12:19:59 +000082#define PUD_ORDER aieeee_attempt_to_allocate_pud
Linus Torvalds1da177e2005-04-16 15:20:36 -070083#define PMD_ORDER 0
84#define PTE_ORDER 0
85#endif
86#ifdef CONFIG_PAGE_SIZE_64KB
87#define PGD_ORDER 0
Ralf Baechlec6e8b582005-02-10 12:19:59 +000088#define PUD_ORDER aieeee_attempt_to_allocate_pud
Linus Torvalds1da177e2005-04-16 15:20:36 -070089#define PMD_ORDER 0
90#define PTE_ORDER 0
91#endif
92
93#define PTRS_PER_PGD ((PAGE_SIZE << PGD_ORDER) / sizeof(pgd_t))
94#define PTRS_PER_PMD ((PAGE_SIZE << PMD_ORDER) / sizeof(pmd_t))
95#define PTRS_PER_PTE ((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t))
96
Peter Watkins9dbd7b92006-08-23 11:15:49 -040097#if PGDIR_SIZE >= TASK_SIZE
98#define USER_PTRS_PER_PGD (1)
99#else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100#define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE)
Peter Watkins9dbd7b92006-08-23 11:15:49 -0400101#endif
102#define FIRST_USER_ADDRESS 0UL
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103
Thiemo Seuferf29244a2005-02-21 11:11:32 +0000104#define VMALLOC_START MAP_BASE
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105#define VMALLOC_END \
106 (VMALLOC_START + PTRS_PER_PGD * PTRS_PER_PMD * PTRS_PER_PTE * PAGE_SIZE)
Franck Bui-Huu054c51b2007-02-15 14:21:36 +0100107#if defined(CONFIG_MODULES) && defined(KBUILD_64BIT_SYM32) && \
Atsushi Nemoto656be922006-10-26 00:08:31 +0900108 VMALLOC_START != CKSSEG
109/* Load modules into 32bit-compatible segment. */
110#define MODULE_START CKSSEG
111#define MODULE_END (FIXADDR_START-2*PAGE_SIZE)
112extern pgd_t module_pg_dir[PTRS_PER_PGD];
113#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114
115#define pte_ERROR(e) \
116 printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
117#define pmd_ERROR(e) \
118 printk("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
119#define pgd_ERROR(e) \
120 printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
121
Ralf Baechlec6e8b582005-02-10 12:19:59 +0000122extern pte_t invalid_pte_table[PTRS_PER_PTE];
123extern pte_t empty_bad_page_table[PTRS_PER_PTE];
124extern pmd_t invalid_pmd_table[PTRS_PER_PMD];
125extern pmd_t empty_bad_pmd_table[PTRS_PER_PMD];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126
127/*
Thiemo Seufer1b3a6e92005-04-01 14:07:13 +0000128 * Empty pgd/pmd entries point to the invalid_pte_table.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700129 */
130static inline int pmd_none(pmd_t pmd)
131{
132 return pmd_val(pmd) == (unsigned long) invalid_pte_table;
133}
134
135#define pmd_bad(pmd) (pmd_val(pmd) & ~PAGE_MASK)
136
137static inline int pmd_present(pmd_t pmd)
138{
139 return pmd_val(pmd) != (unsigned long) invalid_pte_table;
140}
141
142static inline void pmd_clear(pmd_t *pmdp)
143{
144 pmd_val(*pmdp) = ((unsigned long) invalid_pte_table);
145}
146
147/*
Thiemo Seuferf29244a2005-02-21 11:11:32 +0000148 * Empty pud entries point to the invalid_pmd_table.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149 */
Ralf Baechlec6e8b582005-02-10 12:19:59 +0000150static inline int pud_none(pud_t pud)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151{
Ralf Baechlec6e8b582005-02-10 12:19:59 +0000152 return pud_val(pud) == (unsigned long) invalid_pmd_table;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153}
154
Ralf Baechlec6e8b582005-02-10 12:19:59 +0000155static inline int pud_bad(pud_t pud)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156{
Ralf Baechlec6e8b582005-02-10 12:19:59 +0000157 return pud_val(pud) & ~PAGE_MASK;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158}
159
Ralf Baechlec6e8b582005-02-10 12:19:59 +0000160static inline int pud_present(pud_t pud)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161{
Ralf Baechlec6e8b582005-02-10 12:19:59 +0000162 return pud_val(pud) != (unsigned long) invalid_pmd_table;
163}
164
165static inline void pud_clear(pud_t *pudp)
166{
167 pud_val(*pudp) = ((unsigned long) invalid_pmd_table);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168}
169
Thiemo Seufer1b3a6e92005-04-01 14:07:13 +0000170#define pte_page(x) pfn_to_page(pte_pfn(x))
171
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172#ifdef CONFIG_CPU_VR41XX
173#define pte_pfn(x) ((unsigned long)((x).pte >> (PAGE_SHIFT + 2)))
174#define pfn_pte(pfn, prot) __pte(((pfn) << (PAGE_SHIFT + 2)) | pgprot_val(prot))
175#else
176#define pte_pfn(x) ((unsigned long)((x).pte >> PAGE_SHIFT))
177#define pfn_pte(pfn, prot) __pte(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
178#endif
179
180#define __pgd_offset(address) pgd_index(address)
Thiemo Seuferf29244a2005-02-21 11:11:32 +0000181#define __pud_offset(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
Thiemo Seufer1b3a6e92005-04-01 14:07:13 +0000182#define __pmd_offset(address) pmd_index(address)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183
184/* to find an entry in a kernel page-table-directory */
Atsushi Nemoto656be922006-10-26 00:08:31 +0900185#ifdef MODULE_START
186#define pgd_offset_k(address) \
187 ((address) >= MODULE_START ? module_pg_dir : pgd_offset(&init_mm, 0UL))
188#else
Ralf Baechle242954b2006-10-24 02:29:01 +0100189#define pgd_offset_k(address) pgd_offset(&init_mm, 0UL)
Atsushi Nemoto656be922006-10-26 00:08:31 +0900190#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191
Thiemo Seuferf29244a2005-02-21 11:11:32 +0000192#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
Thiemo Seufer1b3a6e92005-04-01 14:07:13 +0000193#define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194
195/* to find an entry in a page-table-directory */
Ralf Baechle21a151d2007-10-11 23:46:15 +0100196#define pgd_offset(mm, addr) ((mm)->pgd + pgd_index(addr))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197
Dave McCracken46a82b22006-09-25 23:31:48 -0700198static inline unsigned long pud_page_vaddr(pud_t pud)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199{
Ralf Baechlec6e8b582005-02-10 12:19:59 +0000200 return pud_val(pud);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201}
Franck Bui-Huuc9d06962007-03-19 17:36:42 +0100202#define pud_phys(pud) virt_to_phys((void *)pud_val(pud))
Dave McCracken46a82b22006-09-25 23:31:48 -0700203#define pud_page(pud) (pfn_to_page(pud_phys(pud) >> PAGE_SHIFT))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204
205/* Find an entry in the second-level page table.. */
Ralf Baechlec6e8b582005-02-10 12:19:59 +0000206static inline pmd_t *pmd_offset(pud_t * pud, unsigned long address)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207{
Dave McCracken46a82b22006-09-25 23:31:48 -0700208 return (pmd_t *) pud_page_vaddr(*pud) + pmd_index(address);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209}
210
211/* Find an entry in the third-level page table.. */
212#define __pte_offset(address) \
213 (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
214#define pte_offset(dir, address) \
Franck Bui-Huu5b70a312006-12-05 10:39:56 +0100215 ((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216#define pte_offset_kernel(dir, address) \
Franck Bui-Huu5b70a312006-12-05 10:39:56 +0100217 ((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218#define pte_offset_map(dir, address) \
219 ((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
220#define pte_offset_map_nested(dir, address) \
221 ((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
222#define pte_unmap(pte) ((void)(pte))
223#define pte_unmap_nested(pte) ((void)(pte))
224
225/*
226 * Initialize a new pgd / pmd table with invalid pointers.
227 */
228extern void pgd_init(unsigned long page);
229extern void pmd_init(unsigned long page, unsigned long pagetable);
230
231/*
232 * Non-present pages: high 24 bits are offset, next 8 bits type,
233 * low 32 bits zero.
234 */
235static inline pte_t mk_swap_pte(unsigned long type, unsigned long offset)
236{ pte_t pte; pte_val(pte) = (type << 32) | (offset << 40); return pte; }
237
238#define __swp_type(x) (((x).val >> 32) & 0xff)
239#define __swp_offset(x) ((x).val >> 40)
Ralf Baechle21a151d2007-10-11 23:46:15 +0100240#define __swp_entry(type, offset) ((swp_entry_t) { pte_val(mk_swap_pte((type), (offset))) })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
242#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
243
244/*
Sergei Shtylyov7cb710c2006-05-27 22:39:39 +0400245 * Bits 0, 4, 6, and 7 are taken. Let's leave bits 1, 2, 3, and 5 alone to
246 * make things easier, and only use the upper 56 bits for the page offset...
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247 */
Sergei Shtylyov7cb710c2006-05-27 22:39:39 +0400248#define PTE_FILE_MAX_BITS 56
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249
Sergei Shtylyov7cb710c2006-05-27 22:39:39 +0400250#define pte_to_pgoff(_pte) ((_pte).pte >> 8)
251#define pgoff_to_pte(off) ((pte_t) { ((off) << 8) | _PAGE_FILE })
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252
253#endif /* _ASM_PGTABLE_64_H */