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) 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
12 #include <linux/compiler.h>
13 #include <linux/linkage.h>
14
15 #include <asm/addrspace.h>
16 #include <asm/page.h>
17 #include <asm/cachectl.h>
18 #include <asm/fixmap.h>
19
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>
25 #else
26 #include <asm-generic/5level-fixup.h>
27 #endif
28
29 /*
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.
37 *
38 * Kernel mappings: kernel mappings are held in the swapper_pg_table.
39 * The layout is identical to userspace except it's indexed with the
40 * fault address - VMALLOC_START.
41 */
42
43
44 /* PGDIR_SHIFT determines what a third-level page table entry can map */
45 #ifdef __PAGETABLE_PMD_FOLDED
46 #define PGDIR_SHIFT (PAGE_SHIFT + PAGE_SHIFT + PTE_ORDER - 3)
47 #else
48
49 /* PMD_SHIFT determines the size of the area a second-level page table can map */
50 #define PMD_SHIFT (PAGE_SHIFT + (PAGE_SHIFT + PTE_ORDER - 3))
51 #define PMD_SIZE (1UL << PMD_SHIFT)
52 #define PMD_MASK (~(PMD_SIZE-1))
53
54 # ifdef __PAGETABLE_PUD_FOLDED
55 # define PGDIR_SHIFT (PMD_SHIFT + (PAGE_SHIFT + PMD_ORDER - 3))
56 # endif
57 #endif
58
59 #ifndef __PAGETABLE_PUD_FOLDED
60 #define PUD_SHIFT (PMD_SHIFT + (PAGE_SHIFT + PMD_ORDER - 3))
61 #define PUD_SIZE (1UL << PUD_SHIFT)
62 #define PUD_MASK (~(PUD_SIZE-1))
63 #define PGDIR_SHIFT (PUD_SHIFT + (PAGE_SHIFT + PUD_ORDER - 3))
64 #endif
65
66 #define PGDIR_SIZE (1UL << PGDIR_SHIFT)
67 #define PGDIR_MASK (~(PGDIR_SIZE-1))
68
69 /*
70 * For 4kB page size we use a 3 level page tree and an 8kB pud, which
71 * permits us mapping 40 bits of virtual address space.
72 *
73 * We used to implement 41 bits by having an order 1 pmd level but that seemed
74 * rather pointless.
75 *
76 * For 8kB page size we use a 3 level page tree which permits a total of
77 * 8TB of address space. Alternatively a 33-bit / 8GB organization using
78 * two levels would be easy to implement.
79 *
80 * For 16kB page size we use a 2 level page tree which permits a total of
81 * 36 bits of virtual address space. We could add a third level but it seems
82 * like at the moment there's no need for this.
83 *
84 * For 64kB page size we use a 2 level page table tree for a total of 42 bits
85 * of virtual address space.
86 */
87 #ifdef CONFIG_PAGE_SIZE_4KB
88 # ifdef CONFIG_MIPS_VA_BITS_48
89 # define PGD_ORDER 0
90 # define PUD_ORDER 0
91 # else
92 # define PGD_ORDER 1
93 # define PUD_ORDER aieeee_attempt_to_allocate_pud
94 # endif
95 #define PMD_ORDER 0
96 #define PTE_ORDER 0
97 #endif
98 #ifdef CONFIG_PAGE_SIZE_8KB
99 #define PGD_ORDER 0
100 #define PUD_ORDER aieeee_attempt_to_allocate_pud
101 #define PMD_ORDER 0
102 #define PTE_ORDER 0
103 #endif
104 #ifdef CONFIG_PAGE_SIZE_16KB
105 #ifdef CONFIG_MIPS_VA_BITS_48
106 #define PGD_ORDER 1
107 #else
108 #define PGD_ORDER 0
109 #endif
110 #define PUD_ORDER aieeee_attempt_to_allocate_pud
111 #define PMD_ORDER 0
112 #define PTE_ORDER 0
113 #endif
114 #ifdef CONFIG_PAGE_SIZE_32KB
115 #define PGD_ORDER 0
116 #define PUD_ORDER aieeee_attempt_to_allocate_pud
117 #define PMD_ORDER 0
118 #define PTE_ORDER 0
119 #endif
120 #ifdef CONFIG_PAGE_SIZE_64KB
121 #define PGD_ORDER 0
122 #define PUD_ORDER aieeee_attempt_to_allocate_pud
123 #ifdef CONFIG_MIPS_VA_BITS_48
124 #define PMD_ORDER 0
125 #else
126 #define PMD_ORDER aieeee_attempt_to_allocate_pmd
127 #endif
128 #define PTE_ORDER 0
129 #endif
130
131 #define PTRS_PER_PGD ((PAGE_SIZE << PGD_ORDER) / sizeof(pgd_t))
132 #ifndef __PAGETABLE_PUD_FOLDED
133 #define PTRS_PER_PUD ((PAGE_SIZE << PUD_ORDER) / sizeof(pud_t))
134 #endif
135 #ifndef __PAGETABLE_PMD_FOLDED
136 #define PTRS_PER_PMD ((PAGE_SIZE << PMD_ORDER) / sizeof(pmd_t))
137 #endif
138 #define PTRS_PER_PTE ((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t))
139
140 #define USER_PTRS_PER_PGD ((TASK_SIZE64 / PGDIR_SIZE)?(TASK_SIZE64 / PGDIR_SIZE):1)
141 #define FIRST_USER_ADDRESS 0UL
142
143 /*
144 * TLB refill handlers also map the vmalloc area into xuseg. Avoid
145 * the first couple of pages so NULL pointer dereferences will still
146 * reliably trap.
147 */
148 #define VMALLOC_START (MAP_BASE + (2 * PAGE_SIZE))
149 #define VMALLOC_END \
150 (MAP_BASE + \
151 min(PTRS_PER_PGD * PTRS_PER_PUD * PTRS_PER_PMD * PTRS_PER_PTE * PAGE_SIZE, \
152 (1UL << cpu_vmbits)) - (1UL << 32))
153
154 #if defined(CONFIG_MODULES) && defined(KBUILD_64BIT_SYM32) && \
155 VMALLOC_START != CKSSEG
156 /* Load modules into 32bit-compatible segment. */
157 #define MODULE_START CKSSEG
158 #define MODULE_END (FIXADDR_START-2*PAGE_SIZE)
159 #endif
160
161 #define pte_ERROR(e) \
162 printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
163 #ifndef __PAGETABLE_PMD_FOLDED
164 #define pmd_ERROR(e) \
165 printk("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
166 #endif
167 #ifndef __PAGETABLE_PUD_FOLDED
168 #define pud_ERROR(e) \
169 printk("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e))
170 #endif
171 #define pgd_ERROR(e) \
172 printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
173
174 extern pte_t invalid_pte_table[PTRS_PER_PTE];
175
176 #ifndef __PAGETABLE_PUD_FOLDED
177 /*
178 * For 4-level pagetables we defines these ourselves, for 3-level the
179 * definitions are below, for 2-level the
180 * definitions are supplied by <asm-generic/pgtable-nopmd.h>.
181 */
182 typedef struct { unsigned long pud; } pud_t;
183 #define pud_val(x) ((x).pud)
184 #define __pud(x) ((pud_t) { (x) })
185
186 extern pud_t invalid_pud_table[PTRS_PER_PUD];
187
188 /*
189 * Empty pgd entries point to the invalid_pud_table.
190 */
pgd_none(pgd_t pgd)191 static inline int pgd_none(pgd_t pgd)
192 {
193 return pgd_val(pgd) == (unsigned long)invalid_pud_table;
194 }
195
pgd_bad(pgd_t pgd)196 static inline int pgd_bad(pgd_t pgd)
197 {
198 if (unlikely(pgd_val(pgd) & ~PAGE_MASK))
199 return 1;
200
201 return 0;
202 }
203
pgd_present(pgd_t pgd)204 static inline int pgd_present(pgd_t pgd)
205 {
206 return pgd_val(pgd) != (unsigned long)invalid_pud_table;
207 }
208
pgd_clear(pgd_t * pgdp)209 static inline void pgd_clear(pgd_t *pgdp)
210 {
211 pgd_val(*pgdp) = (unsigned long)invalid_pud_table;
212 }
213
214 #define pud_index(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD - 1))
215
pgd_page_vaddr(pgd_t pgd)216 static inline unsigned long pgd_page_vaddr(pgd_t pgd)
217 {
218 return pgd_val(pgd);
219 }
220
221 #define pgd_phys(pgd) virt_to_phys((void *)pgd_val(pgd))
222 #define pgd_page(pgd) (pfn_to_page(pgd_phys(pgd) >> PAGE_SHIFT))
223
pud_offset(pgd_t * pgd,unsigned long address)224 static inline pud_t *pud_offset(pgd_t *pgd, unsigned long address)
225 {
226 return (pud_t *)pgd_page_vaddr(*pgd) + pud_index(address);
227 }
228
set_pgd(pgd_t * pgd,pgd_t pgdval)229 static inline void set_pgd(pgd_t *pgd, pgd_t pgdval)
230 {
231 *pgd = pgdval;
232 }
233
234 #endif
235
236 #ifndef __PAGETABLE_PMD_FOLDED
237 /*
238 * For 3-level pagetables we defines these ourselves, for 2-level the
239 * definitions are supplied by <asm-generic/pgtable-nopmd.h>.
240 */
241 typedef struct { unsigned long pmd; } pmd_t;
242 #define pmd_val(x) ((x).pmd)
243 #define __pmd(x) ((pmd_t) { (x) } )
244
245
246 extern pmd_t invalid_pmd_table[PTRS_PER_PMD];
247 #endif
248
249 /*
250 * Empty pgd/pmd entries point to the invalid_pte_table.
251 */
pmd_none(pmd_t pmd)252 static inline int pmd_none(pmd_t pmd)
253 {
254 return pmd_val(pmd) == (unsigned long) invalid_pte_table;
255 }
256
pmd_bad(pmd_t pmd)257 static inline int pmd_bad(pmd_t pmd)
258 {
259 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
260 /* pmd_huge(pmd) but inline */
261 if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
262 return 0;
263 #endif
264
265 if (unlikely(pmd_val(pmd) & ~PAGE_MASK))
266 return 1;
267
268 return 0;
269 }
270
pmd_present(pmd_t pmd)271 static inline int pmd_present(pmd_t pmd)
272 {
273 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
274 if (unlikely(pmd_val(pmd) & _PAGE_HUGE))
275 return pmd_val(pmd) & _PAGE_PRESENT;
276 #endif
277
278 return pmd_val(pmd) != (unsigned long) invalid_pte_table;
279 }
280
pmd_clear(pmd_t * pmdp)281 static inline void pmd_clear(pmd_t *pmdp)
282 {
283 pmd_val(*pmdp) = ((unsigned long) invalid_pte_table);
284 }
285 #ifndef __PAGETABLE_PMD_FOLDED
286
287 /*
288 * Empty pud entries point to the invalid_pmd_table.
289 */
pud_none(pud_t pud)290 static inline int pud_none(pud_t pud)
291 {
292 return pud_val(pud) == (unsigned long) invalid_pmd_table;
293 }
294
pud_bad(pud_t pud)295 static inline int pud_bad(pud_t pud)
296 {
297 return pud_val(pud) & ~PAGE_MASK;
298 }
299
pud_present(pud_t pud)300 static inline int pud_present(pud_t pud)
301 {
302 return pud_val(pud) != (unsigned long) invalid_pmd_table;
303 }
304
pud_clear(pud_t * pudp)305 static inline void pud_clear(pud_t *pudp)
306 {
307 pud_val(*pudp) = ((unsigned long) invalid_pmd_table);
308 }
309 #endif
310
311 #define pte_page(x) pfn_to_page(pte_pfn(x))
312
313 #ifdef CONFIG_CPU_VR41XX
314 #define pte_pfn(x) ((unsigned long)((x).pte >> (PAGE_SHIFT + 2)))
315 #define pfn_pte(pfn, prot) __pte(((pfn) << (PAGE_SHIFT + 2)) | pgprot_val(prot))
316 #else
317 #define pte_pfn(x) ((unsigned long)((x).pte >> _PFN_SHIFT))
318 #define pfn_pte(pfn, prot) __pte(((pfn) << _PFN_SHIFT) | pgprot_val(prot))
319 #define pfn_pmd(pfn, prot) __pmd(((pfn) << _PFN_SHIFT) | pgprot_val(prot))
320 #endif
321
322 #define __pgd_offset(address) pgd_index(address)
323 #define __pud_offset(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
324 #define __pmd_offset(address) pmd_index(address)
325
326 /* to find an entry in a kernel page-table-directory */
327 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
328
329 #define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
330 #define pmd_index(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
331
332 /* to find an entry in a page-table-directory */
333 #define pgd_offset(mm, addr) ((mm)->pgd + pgd_index(addr))
334
335 #ifndef __PAGETABLE_PMD_FOLDED
pud_page_vaddr(pud_t pud)336 static inline unsigned long pud_page_vaddr(pud_t pud)
337 {
338 return pud_val(pud);
339 }
340 #define pud_phys(pud) virt_to_phys((void *)pud_val(pud))
341 #define pud_page(pud) (pfn_to_page(pud_phys(pud) >> PAGE_SHIFT))
342
343 /* Find an entry in the second-level page table.. */
pmd_offset(pud_t * pud,unsigned long address)344 static inline pmd_t *pmd_offset(pud_t * pud, unsigned long address)
345 {
346 return (pmd_t *) pud_page_vaddr(*pud) + pmd_index(address);
347 }
348 #endif
349
350 /* Find an entry in the third-level page table.. */
351 #define __pte_offset(address) \
352 (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
353 #define pte_offset(dir, address) \
354 ((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
355 #define pte_offset_kernel(dir, address) \
356 ((pte_t *) pmd_page_vaddr(*(dir)) + __pte_offset(address))
357 #define pte_offset_map(dir, address) \
358 ((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
359 #define pte_unmap(pte) ((void)(pte))
360
361 /*
362 * Initialize a new pgd / pmd table with invalid pointers.
363 */
364 extern void pgd_init(unsigned long page);
365 extern void pud_init(unsigned long page, unsigned long pagetable);
366 extern void pmd_init(unsigned long page, unsigned long pagetable);
367
368 /*
369 * Non-present pages: high 40 bits are offset, next 8 bits type,
370 * low 16 bits zero.
371 */
mk_swap_pte(unsigned long type,unsigned long offset)372 static inline pte_t mk_swap_pte(unsigned long type, unsigned long offset)
373 { pte_t pte; pte_val(pte) = (type << 16) | (offset << 24); return pte; }
374
375 #define __swp_type(x) (((x).val >> 16) & 0xff)
376 #define __swp_offset(x) ((x).val >> 24)
377 #define __swp_entry(type, offset) ((swp_entry_t) { pte_val(mk_swap_pte((type), (offset))) })
378 #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
379 #define __swp_entry_to_pte(x) ((pte_t) { (x).val })
380
381 #endif /* _ASM_PGTABLE_64_H */
382