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
6 * Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 2003 Ralf Baechle
7 * Copyright (C) 1999, 2000, 2001 Silicon Graphics, Inc.
9 #ifndef _ASM_PGTABLE_64_H
10 #define _ASM_PGTABLE_64_H
12 #include <linux/compiler.h>
13 #include <linux/linkage.h>
15 #include <asm/addrspace.h>
17 #include <asm/cachectl.h>
18 #include <asm/fixmap.h>
20 #define __ARCH_USE_5LEVEL_HACK
21 #if CONFIG_PGTABLE_LEVELS == 2
22 #include <asm-generic/pgtable-nopmd.h>
23 #elif CONFIG_PGTABLE_LEVELS == 3
24 #include <asm-generic/pgtable-nopud.h>
26 #include <asm-generic/5level-fixup.h>
30 * Each address space has 2 4K pages as its page directory, giving 1024
31 * (== PTRS_PER_PGD) 8 byte pointers to pmd tables. Each pmd table is a
32 * single 4K page, giving 512 (== PTRS_PER_PMD) 8 byte pointers to page
33 * tables. Each page table is also a single 4K page, giving 512 (==
34 * PTRS_PER_PTE) 8 byte ptes. Each pud entry is initialized to point to
35 * invalid_pmd_table, each pmd entry is initialized to point to
36 * invalid_pte_table, each pte is initialized to 0. When memory is low,
37 * and a pmd table or a page table allocation fails, empty_bad_pmd_table
38 * and empty_bad_page_table is returned back to higher layer code, so
39 * that the failure is recognized later on. Linux does not seem to
40 * handle these failures very well though. The empty_bad_page_table has
41 * invalid pte entries in it, to force page faults.
43 * Kernel mappings: kernel mappings are held in the swapper_pg_table.
44 * The layout is identical to userspace except it's indexed with the
45 * fault address - VMALLOC_START.
49 /* PGDIR_SHIFT determines what a third-level page table entry can map */
50 #ifdef __PAGETABLE_PMD_FOLDED
51 #define PGDIR_SHIFT (PAGE_SHIFT + PAGE_SHIFT + PTE_ORDER - 3)
54 /* PMD_SHIFT determines the size of the area a second-level page table can map */
55 #define PMD_SHIFT (PAGE_SHIFT + (PAGE_SHIFT + PTE_ORDER - 3))
56 #define PMD_SIZE (1UL << PMD_SHIFT)
57 #define PMD_MASK (~(PMD_SIZE-1))
59 # ifdef __PAGETABLE_PUD_FOLDED
60 # define PGDIR_SHIFT (PMD_SHIFT + (PAGE_SHIFT + PMD_ORDER - 3))
64 #ifndef __PAGETABLE_PUD_FOLDED
65 #define PUD_SHIFT (PMD_SHIFT + (PAGE_SHIFT + PMD_ORDER - 3))
66 #define PUD_SIZE (1UL << PUD_SHIFT)
67 #define PUD_MASK (~(PUD_SIZE-1))
68 #define PGDIR_SHIFT (PUD_SHIFT + (PAGE_SHIFT + PUD_ORDER - 3))
71 #define PGDIR_SIZE (1UL << PGDIR_SHIFT)
72 #define PGDIR_MASK (~(PGDIR_SIZE-1))
75 * For 4kB page size we use a 3 level page tree and an 8kB pud, which
76 * permits us mapping 40 bits of virtual address space.
78 * We used to implement 41 bits by having an order 1 pmd level but that seemed
81 * For 8kB page size we use a 3 level page tree which permits a total of
82 * 8TB of address space. Alternatively a 33-bit / 8GB organization using
83 * two levels would be easy to implement.
85 * For 16kB page size we use a 2 level page tree which permits a total of
86 * 36 bits of virtual address space. We could add a third level but it seems
87 * like at the moment there's no need for this.
89 * For 64kB page size we use a 2 level page table tree for a total of 42 bits
90 * of virtual address space.
92 #ifdef CONFIG_PAGE_SIZE_4KB
93 # ifdef CONFIG_MIPS_VA_BITS_48
98 # define PUD_ORDER aieeee_attempt_to_allocate_pud
103 #ifdef CONFIG_PAGE_SIZE_8KB
105 #define PUD_ORDER aieeee_attempt_to_allocate_pud
109 #ifdef CONFIG_PAGE_SIZE_16KB
110 #ifdef CONFIG_MIPS_VA_BITS_48
115 #define PUD_ORDER aieeee_attempt_to_allocate_pud
119 #ifdef CONFIG_PAGE_SIZE_32KB
121 #define PUD_ORDER aieeee_attempt_to_allocate_pud
125 #ifdef CONFIG_PAGE_SIZE_64KB
127 #define PUD_ORDER aieeee_attempt_to_allocate_pud
128 #ifdef CONFIG_MIPS_VA_BITS_48
131 #define PMD_ORDER aieeee_attempt_to_allocate_pmd
136 #define PTRS_PER_PGD ((PAGE_SIZE << PGD_ORDER) / sizeof(pgd_t))
137 #ifndef __PAGETABLE_PUD_FOLDED
138 #define PTRS_PER_PUD ((PAGE_SIZE << PUD_ORDER) / sizeof(pud_t))
140 #ifndef __PAGETABLE_PMD_FOLDED
141 #define PTRS_PER_PMD ((PAGE_SIZE << PMD_ORDER) / sizeof(pmd_t))
143 #define PTRS_PER_PTE ((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t))
145 #define USER_PTRS_PER_PGD ((TASK_SIZE64 / PGDIR_SIZE)?(TASK_SIZE64 / PGDIR_SIZE):1)
146 #define FIRST_USER_ADDRESS 0UL
149 * TLB refill handlers also map the vmalloc area into xuseg. Avoid
150 * the first couple of pages so NULL pointer dereferences will still
153 #define VMALLOC_START (MAP_BASE + (2 * PAGE_SIZE))
154 #define VMALLOC_END \
156 min(PTRS_PER_PGD * PTRS_PER_PUD * PTRS_PER_PMD * PTRS_PER_PTE * PAGE_SIZE, \
157 (1UL << cpu_vmbits)) - (1UL << 32))
159 #if defined(CONFIG_MODULES) && defined(KBUILD_64BIT_SYM32) && \
160 VMALLOC_START != CKSSEG
161 /* Load modules into 32bit-compatible segment. */
162 #define MODULE_START CKSSEG
163 #define MODULE_END (FIXADDR_START-2*PAGE_SIZE)
166 #define pte_ERROR(e) \
167 printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
168 #ifndef __PAGETABLE_PMD_FOLDED
169 #define pmd_ERROR(e) \
170 printk("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
172 #ifndef __PAGETABLE_PUD_FOLDED
173 #define pud_ERROR(e) \
174 printk("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e))
176 #define pgd_ERROR(e) \
177 printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
179 extern pte_t invalid_pte_table[PTRS_PER_PTE];
180 extern pte_t empty_bad_page_table[PTRS_PER_PTE];
182 #ifndef __PAGETABLE_PUD_FOLDED
184 * For 4-level pagetables we defines these ourselves, for 3-level the
185 * definitions are below, for 2-level the
186 * definitions are supplied by <asm-generic/pgtable-nopmd.h>.
188 typedef struct { unsigned long pud; } pud_t;
189 #define pud_val(x) ((x).pud)
190 #define __pud(x) ((pud_t) { (x) })
192 extern pud_t invalid_pud_table[PTRS_PER_PUD];
195 * Empty pgd entries point to the invalid_pud_table.
197 static inline int pgd_none(pgd_t pgd)
199 return pgd_val(pgd) == (unsigned long)invalid_pud_table;
202 static inline int pgd_bad(pgd_t pgd)
204 if (unlikely(pgd_val(pgd) & ~PAGE_MASK))
210 static inline int pgd_present(pgd_t pgd)
212 return pgd_val(pgd) != (unsigned long)invalid_pud_table;
215 static inline void pgd_clear(pgd_t *pgdp)
217 pgd_val(*pgdp) = (unsigned long)invalid_pud_table;
220 #define pud_index(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
222 static inline unsigned long pgd_page_vaddr(pgd_t pgd)
227 #define pgd_phys(pgd) virt_to_phys((void *)pgd_val(pgd))
228 #define pgd_page(pgd) (pfn_to_page(pgd_phys(pgd) >> PAGE_SHIFT))
230 static inline pud_t *pud_offset(pgd_t *pgd, unsigned long address)
232 return (pud_t *)pgd_page_vaddr(*pgd) + pud_index(address);
235 static inline void set_pgd(pgd_t *pgd, pgd_t pgdval)
242 #ifndef __PAGETABLE_PMD_FOLDED
244 * For 3-level pagetables we defines these ourselves, for 2-level the
245 * definitions are supplied by <asm-generic/pgtable-nopmd.h>.
247 typedef struct { unsigned long pmd; } pmd_t;
248 #define pmd_val(x) ((x).pmd)
249 #define __pmd(x) ((pmd_t) { (x) } )
252 extern pmd_t invalid_pmd_table[PTRS_PER_PMD];
256 * Empty pgd/pmd entries point to the invalid_pte_table.
258 static inline int pmd_none(pmd_t pmd)
260 return pmd_val(pmd) == (unsigned long) invalid_pte_table;
263 static inline int pmd_bad(pmd_t pmd)
265 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
266 /* pmd_huge(pmd) but inline */
267 if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
271 if (unlikely(pmd_val(pmd) & ~PAGE_MASK))
277 static inline int pmd_present(pmd_t pmd)
279 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
280 if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
281 return pmd_val(pmd) & _PAGE_PRESENT;
284 return pmd_val(pmd) != (unsigned long) invalid_pte_table;
287 static inline void pmd_clear(pmd_t *pmdp)
289 pmd_val(*pmdp) = ((unsigned long) invalid_pte_table);
291 #ifndef __PAGETABLE_PMD_FOLDED
294 * Empty pud entries point to the invalid_pmd_table.
296 static inline int pud_none(pud_t pud)
298 return pud_val(pud) == (unsigned long) invalid_pmd_table;
301 static inline int pud_bad(pud_t pud)
303 return pud_val(pud) & ~PAGE_MASK;
306 static inline int pud_present(pud_t pud)
308 return pud_val(pud) != (unsigned long) invalid_pmd_table;
311 static inline void pud_clear(pud_t *pudp)
313 pud_val(*pudp) = ((unsigned long) invalid_pmd_table);
317 #define pte_page(x) pfn_to_page(pte_pfn(x))
319 #ifdef CONFIG_CPU_VR41XX
320 #define pte_pfn(x) ((unsigned long)((x).pte >> (PAGE_SHIFT + 2)))
321 #define pfn_pte(pfn, prot) __pte(((pfn) << (PAGE_SHIFT + 2)) | pgprot_val(prot))
323 #define pte_pfn(x) ((unsigned long)((x).pte >> _PFN_SHIFT))
324 #define pfn_pte(pfn, prot) __pte(((pfn) << _PFN_SHIFT) | pgprot_val(prot))
325 #define pfn_pmd(pfn, prot) __pmd(((pfn) << _PFN_SHIFT) | pgprot_val(prot))
328 #define __pgd_offset(address) pgd_index(address)
329 #define __pud_offset(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
330 #define __pmd_offset(address) pmd_index(address)
332 /* to find an entry in a kernel page-table-directory */
333 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
335 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
336 #define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
338 /* to find an entry in a page-table-directory */
339 #define pgd_offset(mm, addr) ((mm)->pgd + pgd_index(addr))
341 #ifndef __PAGETABLE_PMD_FOLDED
342 static inline unsigned long pud_page_vaddr(pud_t pud)
346 #define pud_phys(pud) virt_to_phys((void *)pud_val(pud))
347 #define pud_page(pud) (pfn_to_page(pud_phys(pud) >> PAGE_SHIFT))
349 /* Find an entry in the second-level page table.. */
350 static inline pmd_t *pmd_offset(pud_t * pud, unsigned long address)
352 return (pmd_t *) pud_page_vaddr(*pud) + pmd_index(address);
356 /* Find an entry in the third-level page table.. */
357 #define __pte_offset(address) \
358 (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
359 #define pte_offset(dir, address) \
360 ((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
361 #define pte_offset_kernel(dir, address) \
362 ((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
363 #define pte_offset_map(dir, address) \
364 ((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
365 #define pte_unmap(pte) ((void)(pte))
368 * Initialize a new pgd / pmd table with invalid pointers.
370 extern void pgd_init(unsigned long page);
371 extern void pud_init(unsigned long page, unsigned long pagetable);
372 extern void pmd_init(unsigned long page, unsigned long pagetable);
375 * Non-present pages: high 40 bits are offset, next 8 bits type,
378 static inline pte_t mk_swap_pte(unsigned long type, unsigned long offset)
379 { pte_t pte; pte_val(pte) = (type << 16) | (offset << 24); return pte; }
381 #define __swp_type(x) (((x).val >> 16) & 0xff)
382 #define __swp_offset(x) ((x).val >> 24)
383 #define __swp_entry(type, offset) ((swp_entry_t) { pte_val(mk_swap_pte((type), (offset))) })
384 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
385 #define __swp_entry_to_pte(x) ((pte_t) { (x).val })
387 #endif /* _ASM_PGTABLE_64_H */