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 #if CONFIG_PGTABLE_LEVELS == 2
21 #include <asm-generic/pgtable-nopmd.h>
22 #elif CONFIG_PGTABLE_LEVELS == 3
23 #include <asm-generic/pgtable-nopud.h>
25 #include <asm-generic/pgtable-nop4d.h>
29 * Each address space has 2 4K pages as its page directory, giving 1024
30 * (== PTRS_PER_PGD) 8 byte pointers to pmd tables. Each pmd table is a
31 * single 4K page, giving 512 (== PTRS_PER_PMD) 8 byte pointers to page
32 * tables. Each page table is also a single 4K page, giving 512 (==
33 * PTRS_PER_PTE) 8 byte ptes. Each pud entry is initialized to point to
34 * invalid_pmd_table, each pmd entry is initialized to point to
35 * invalid_pte_table, each pte is initialized to 0.
37 * Kernel mappings: kernel mappings are held in the swapper_pg_table.
38 * The layout is identical to userspace except it's indexed with the
39 * fault address - VMALLOC_START.
43 /* PGDIR_SHIFT determines what a third-level page table entry can map */
44 #ifdef __PAGETABLE_PMD_FOLDED
45 #define PGDIR_SHIFT (PAGE_SHIFT + PAGE_SHIFT - 3)
48 /* PMD_SHIFT determines the size of the area a second-level page table can map */
49 #define PMD_SHIFT (PAGE_SHIFT + (PAGE_SHIFT - 3))
50 #define PMD_SIZE (1UL << PMD_SHIFT)
51 #define PMD_MASK (~(PMD_SIZE-1))
53 # ifdef __PAGETABLE_PUD_FOLDED
54 # define PGDIR_SHIFT (PMD_SHIFT + (PAGE_SHIFT + PMD_TABLE_ORDER - 3))
58 #ifndef __PAGETABLE_PUD_FOLDED
59 #define PUD_SHIFT (PMD_SHIFT + (PAGE_SHIFT + PMD_TABLE_ORDER - 3))
60 #define PUD_SIZE (1UL << PUD_SHIFT)
61 #define PUD_MASK (~(PUD_SIZE-1))
62 #define PGDIR_SHIFT (PUD_SHIFT + (PAGE_SHIFT + PUD_TABLE_ORDER - 3))
65 #define PGDIR_SIZE (1UL << PGDIR_SHIFT)
66 #define PGDIR_MASK (~(PGDIR_SIZE-1))
69 * For 4kB page size we use a 3 level page tree and an 8kB pud, which
70 * permits us mapping 40 bits of virtual address space.
72 * We used to implement 41 bits by having an order 1 pmd level but that seemed
75 * For 8kB page size we use a 3 level page tree which permits a total of
76 * 8TB of address space. Alternatively a 33-bit / 8GB organization using
77 * two levels would be easy to implement.
79 * For 16kB page size we use a 2 level page tree which permits a total of
80 * 36 bits of virtual address space. We could add a third level but it seems
81 * like at the moment there's no need for this.
83 * For 64kB page size we use a 2 level page table tree for a total of 42 bits
84 * of virtual address space.
86 #ifdef CONFIG_PAGE_SIZE_4KB
87 # ifdef CONFIG_MIPS_VA_BITS_48
88 # define PGD_TABLE_ORDER 0
89 # define PUD_TABLE_ORDER 0
91 # define PGD_TABLE_ORDER 1
92 # define PUD_TABLE_ORDER aieeee_attempt_to_allocate_pud
94 #define PMD_TABLE_ORDER 0
96 #ifdef CONFIG_PAGE_SIZE_8KB
97 #define PGD_TABLE_ORDER 0
98 #define PUD_TABLE_ORDER aieeee_attempt_to_allocate_pud
99 #define PMD_TABLE_ORDER 0
101 #ifdef CONFIG_PAGE_SIZE_16KB
102 #ifdef CONFIG_MIPS_VA_BITS_48
103 #define PGD_TABLE_ORDER 1
105 #define PGD_TABLE_ORDER 0
107 #define PUD_TABLE_ORDER aieeee_attempt_to_allocate_pud
108 #define PMD_TABLE_ORDER 0
110 #ifdef CONFIG_PAGE_SIZE_32KB
111 #define PGD_TABLE_ORDER 0
112 #define PUD_TABLE_ORDER aieeee_attempt_to_allocate_pud
113 #define PMD_TABLE_ORDER 0
115 #ifdef CONFIG_PAGE_SIZE_64KB
116 #define PGD_TABLE_ORDER 0
117 #define PUD_TABLE_ORDER aieeee_attempt_to_allocate_pud
118 #ifdef CONFIG_MIPS_VA_BITS_48
119 #define PMD_TABLE_ORDER 0
121 #define PMD_TABLE_ORDER aieeee_attempt_to_allocate_pmd
125 #define PTRS_PER_PGD ((PAGE_SIZE << PGD_TABLE_ORDER) / sizeof(pgd_t))
126 #ifndef __PAGETABLE_PUD_FOLDED
127 #define PTRS_PER_PUD ((PAGE_SIZE << PUD_TABLE_ORDER) / sizeof(pud_t))
129 #ifndef __PAGETABLE_PMD_FOLDED
130 #define PTRS_PER_PMD ((PAGE_SIZE << PMD_TABLE_ORDER) / sizeof(pmd_t))
132 #define PTRS_PER_PTE (PAGE_SIZE / sizeof(pte_t))
134 #define USER_PTRS_PER_PGD ((TASK_SIZE64 / PGDIR_SIZE)?(TASK_SIZE64 / PGDIR_SIZE):1)
137 * TLB refill handlers also map the vmalloc area into xuseg. Avoid
138 * the first couple of pages so NULL pointer dereferences will still
141 #define VMALLOC_START (MAP_BASE + (2 * PAGE_SIZE))
142 #define VMALLOC_END \
144 min(PTRS_PER_PGD * PTRS_PER_PUD * PTRS_PER_PMD * PTRS_PER_PTE * PAGE_SIZE, \
145 (1UL << cpu_vmbits)) - (1UL << 32))
147 #if defined(CONFIG_MODULES) && defined(KBUILD_64BIT_SYM32) && \
148 VMALLOC_START != CKSSEG
149 /* Load modules into 32bit-compatible segment. */
150 #define MODULES_VADDR CKSSEG
151 #define MODULES_END (FIXADDR_START-2*PAGE_SIZE)
154 #define pte_ERROR(e) \
155 printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
156 #ifndef __PAGETABLE_PMD_FOLDED
157 #define pmd_ERROR(e) \
158 printk("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
160 #ifndef __PAGETABLE_PUD_FOLDED
161 #define pud_ERROR(e) \
162 printk("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e))
164 #define pgd_ERROR(e) \
165 printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
167 extern pte_t invalid_pte_table
[PTRS_PER_PTE
];
169 #ifndef __PAGETABLE_PUD_FOLDED
171 * For 4-level pagetables we defines these ourselves, for 3-level the
172 * definitions are below, for 2-level the
173 * definitions are supplied by <asm-generic/pgtable-nopmd.h>.
175 typedef struct { unsigned long pud
; } pud_t
;
176 #define pud_val(x) ((x).pud)
177 #define __pud(x) ((pud_t) { (x) })
179 extern pud_t invalid_pud_table
[PTRS_PER_PUD
];
182 * Empty pgd entries point to the invalid_pud_table.
184 static inline int p4d_none(p4d_t p4d
)
186 return p4d_val(p4d
) == (unsigned long)invalid_pud_table
;
189 static inline int p4d_bad(p4d_t p4d
)
191 if (unlikely(p4d_val(p4d
) & ~PAGE_MASK
))
197 static inline int p4d_present(p4d_t p4d
)
199 return p4d_val(p4d
) != (unsigned long)invalid_pud_table
;
202 static inline void p4d_clear(p4d_t
*p4dp
)
204 p4d_val(*p4dp
) = (unsigned long)invalid_pud_table
;
207 static inline pud_t
*p4d_pgtable(p4d_t p4d
)
209 return (pud_t
*)p4d_val(p4d
);
212 #define p4d_phys(p4d) virt_to_phys((void *)p4d_val(p4d))
213 #define p4d_page(p4d) (pfn_to_page(p4d_phys(p4d) >> PAGE_SHIFT))
215 #define p4d_index(address) (((address) >> P4D_SHIFT) & (PTRS_PER_P4D - 1))
217 static inline void set_p4d(p4d_t
*p4d
, p4d_t p4dval
)
224 #ifndef __PAGETABLE_PMD_FOLDED
226 * For 3-level pagetables we defines these ourselves, for 2-level the
227 * definitions are supplied by <asm-generic/pgtable-nopmd.h>.
229 typedef struct { unsigned long pmd
; } pmd_t
;
230 #define pmd_val(x) ((x).pmd)
231 #define __pmd(x) ((pmd_t) { (x) } )
234 extern pmd_t invalid_pmd_table
[PTRS_PER_PMD
];
238 * Empty pgd/pmd entries point to the invalid_pte_table.
240 static inline int pmd_none(pmd_t pmd
)
242 return pmd_val(pmd
) == (unsigned long) invalid_pte_table
;
245 static inline int pmd_bad(pmd_t pmd
)
247 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
248 /* pmd_leaf(pmd) but inline */
249 if (unlikely(pmd_val(pmd
) & _PAGE_HUGE
))
253 if (unlikely(pmd_val(pmd
) & ~PAGE_MASK
))
259 static inline int pmd_present(pmd_t pmd
)
261 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
262 if (unlikely(pmd_val(pmd
) & _PAGE_HUGE
))
263 return pmd_val(pmd
) & _PAGE_PRESENT
;
266 return pmd_val(pmd
) != (unsigned long) invalid_pte_table
;
269 static inline void pmd_clear(pmd_t
*pmdp
)
271 pmd_val(*pmdp
) = ((unsigned long) invalid_pte_table
);
273 #ifndef __PAGETABLE_PMD_FOLDED
276 * Empty pud entries point to the invalid_pmd_table.
278 static inline int pud_none(pud_t pud
)
280 return pud_val(pud
) == (unsigned long) invalid_pmd_table
;
283 static inline int pud_bad(pud_t pud
)
285 return pud_val(pud
) & ~PAGE_MASK
;
288 static inline int pud_present(pud_t pud
)
290 return pud_val(pud
) != (unsigned long) invalid_pmd_table
;
293 static inline void pud_clear(pud_t
*pudp
)
295 pud_val(*pudp
) = ((unsigned long) invalid_pmd_table
);
299 #define pte_page(x) pfn_to_page(pte_pfn(x))
301 #define pte_pfn(x) ((unsigned long)((x).pte >> PFN_PTE_SHIFT))
302 #define pfn_pte(pfn, prot) __pte(((pfn) << PFN_PTE_SHIFT) | pgprot_val(prot))
303 #define pfn_pmd(pfn, prot) __pmd(((pfn) << PFN_PTE_SHIFT) | pgprot_val(prot))
305 #ifndef __PAGETABLE_PMD_FOLDED
306 static inline pmd_t
*pud_pgtable(pud_t pud
)
308 return (pmd_t
*)pud_val(pud
);
310 #define pud_phys(pud) virt_to_phys((void *)pud_val(pud))
311 #define pud_page(pud) (pfn_to_page(pud_phys(pud) >> PAGE_SHIFT))
316 * Initialize a new pgd / pud / pmd table with invalid pointers.
318 extern void pgd_init(void *addr
);
319 extern void pud_init(void *addr
);
320 extern void pmd_init(void *addr
);
323 * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
324 * are !pte_none() && !pte_present().
326 * Format of swap PTEs:
328 * 6 6 6 6 5 5 5 5 5 5 5 5 5 5 4 4 4 4 4 4 4 4 4 4 3 3 3 3 3 3 3 3
329 * 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2
330 * <--------------------------- offset ---------------------------
332 * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
333 * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
334 * --------------> E <-- type ---> <---------- zeroes ----------->
336 * E is the exclusive marker that is not stored in swap entries.
338 static inline pte_t
mk_swap_pte(unsigned long type
, unsigned long offset
)
339 { pte_t pte
; pte_val(pte
) = ((type
& 0x7f) << 16) | (offset
<< 24); return pte
; }
341 #define __swp_type(x) (((x).val >> 16) & 0x7f)
342 #define __swp_offset(x) ((x).val >> 24)
343 #define __swp_entry(type, offset) ((swp_entry_t) { pte_val(mk_swap_pte((type), (offset))) })
344 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
345 #define __swp_entry_to_pte(x) ((pte_t) { (x).val })
347 /* We borrow bit 23 to store the exclusive marker in swap PTEs. */
348 #define _PAGE_SWP_EXCLUSIVE (1 << 23)
350 #endif /* _ASM_PGTABLE_64_H */