aboutsummaryrefslogtreecommitdiff
path: root/arch/parisc/include/asm/pgtable.h
blob: 22b89d1edba7a9d24939fa824a378e920dc61755 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
#ifndef _PARISC_PGTABLE_H
#define _PARISC_PGTABLE_H

#include <asm-generic/4level-fixup.h>

#include <asm/fixmap.h>

#ifndef __ASSEMBLY__
/*
 * we simulate an x86-style page table for the linux mm code
 */

#include <linux/bitops.h>
#include <linux/spinlock.h>
#include <linux/mm_types.h>
#include <asm/processor.h>
#include <asm/cache.h>

extern spinlock_t pa_dbit_lock;

/*
 * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
 * memory.  For the return value to be meaningful, ADDR must be >=
 * PAGE_OFFSET.  This operation can be relatively expensive (e.g.,
 * require a hash-, or multi-level tree-lookup or something of that
 * sort) but it guarantees to return TRUE only if accessing the page
 * at that address does not cause an error.  Note that there may be
 * addresses for which kern_addr_valid() returns FALSE even though an
 * access would not cause an error (e.g., this is typically true for
 * memory mapped I/O regions.
 *
 * XXX Need to implement this for parisc.
 */
#define kern_addr_valid(addr)	(1)

/* Certain architectures need to do special things when PTEs
 * within a page table are directly modified.  Thus, the following
 * hook is made available.
 */
#define set_pte(pteptr, pteval)                                 \
        do{                                                     \
                *(pteptr) = (pteval);                           \
        } while(0)

extern void purge_tlb_entries(struct mm_struct *, unsigned long);

#define set_pte_at(mm, addr, ptep, pteval)                      \
	do {                                                    \
		unsigned long flags;				\
		spin_lock_irqsave(&pa_dbit_lock, flags);	\
		set_pte(ptep, pteval);                          \
		purge_tlb_entries(mm, addr);                    \
		spin_unlock_irqrestore(&pa_dbit_lock, flags);	\
	} while (0)

#endif /* !__ASSEMBLY__ */

#include <asm/page.h>

#define pte_ERROR(e) \
	printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
#define pmd_ERROR(e) \
	printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, (unsigned long)pmd_val(e))
#define pgd_ERROR(e) \
	printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, (unsigned long)pgd_val(e))

/* This is the size of the initially mapped kernel memory */
#define KERNEL_INITIAL_ORDER	24	/* 0 to 1<<24 = 16MB */
#define KERNEL_INITIAL_SIZE	(1 << KERNEL_INITIAL_ORDER)

#if defined(CONFIG_64BIT) && defined(CONFIG_PARISC_PAGE_SIZE_4KB)
#define PT_NLEVELS	3
#define PGD_ORDER	1 /* Number of pages per pgd */
#define PMD_ORDER	1 /* Number of pages per pmd */
#define PGD_ALLOC_ORDER	2 /* first pgd contains pmd */
#else
#define PT_NLEVELS	2
#define PGD_ORDER	1 /* Number of pages per pgd */
#define PGD_ALLOC_ORDER	PGD_ORDER
#endif

/* Definitions for 3rd level (we use PLD here for Page Lower directory
 * because PTE_SHIFT is used lower down to mean shift that has to be
 * done to get usable bits out of the PTE) */
#define PLD_SHIFT	PAGE_SHIFT
#define PLD_SIZE	PAGE_SIZE
#define BITS_PER_PTE	(PAGE_SHIFT - BITS_PER_PTE_ENTRY)
#define PTRS_PER_PTE    (1UL << BITS_PER_PTE)

/* Definitions for 2nd level */
#define pgtable_cache_init()	do { } while (0)

#define PMD_SHIFT       (PLD_SHIFT + BITS_PER_PTE)
#define PMD_SIZE	(1UL << PMD_SHIFT)
#define PMD_MASK	(~(PMD_SIZE-1))
#if PT_NLEVELS == 3
#define BITS_PER_PMD	(PAGE_SHIFT + PMD_ORDER - BITS_PER_PMD_ENTRY)
#else
#define BITS_PER_PMD	0
#endif
#define PTRS_PER_PMD    (1UL << BITS_PER_PMD)

/* Definitions for 1st level */
#define PGDIR_SHIFT	(PMD_SHIFT + BITS_PER_PMD)
#if (PGDIR_SHIFT + PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY) > BITS_PER_LONG
#define BITS_PER_PGD	(BITS_PER_LONG - PGDIR_SHIFT)
#else
#define BITS_PER_PGD	(PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY)
#endif
#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
#define PGDIR_MASK	(~(PGDIR_SIZE-1))
#define PTRS_PER_PGD    (1UL << BITS_PER_PGD)
#define USER_PTRS_PER_PGD       PTRS_PER_PGD

#ifdef CONFIG_64BIT
#define MAX_ADDRBITS	(PGDIR_SHIFT + BITS_PER_PGD)
#define MAX_ADDRESS	(1UL << MAX_ADDRBITS)
#define SPACEID_SHIFT	(MAX_ADDRBITS - 32)
#else
#define MAX_ADDRBITS	(BITS_PER_LONG)
#define MAX_ADDRESS	(1UL << MAX_ADDRBITS)
#define SPACEID_SHIFT	0
#endif

/* This calculates the number of initial pages we need for the initial
 * page tables */
#if (KERNEL_INITIAL_ORDER) >= (PMD_SHIFT)
# define PT_INITIAL	(1 << (KERNEL_INITIAL_ORDER - PMD_SHIFT))
#else
# define PT_INITIAL	(1)  /* all initial PTEs fit into one page */
#endif

/*
 * pgd entries used up by user/kernel:
 */

#define FIRST_USER_ADDRESS	0

/* NB: The tlb miss handlers make certain assumptions about the order */
/*     of the following bits, so be careful (One example, bits 25-31  */
/*     are moved together in one instruction).                        */

#define _PAGE_READ_BIT     31   /* (0x001) read access allowed */
#define _PAGE_WRITE_BIT    30   /* (0x002) write access allowed */
#define _PAGE_EXEC_BIT     29   /* (0x004) execute access allowed */
#define _PAGE_GATEWAY_BIT  28   /* (0x008) privilege promotion allowed */
#define _PAGE_DMB_BIT      27   /* (0x010) Data Memory Break enable (B bit) */
#define _PAGE_DIRTY_BIT    26   /* (0x020) Page Dirty (D bit) */
#define _PAGE_FILE_BIT	_PAGE_DIRTY_BIT	/* overload this bit */
#define _PAGE_REFTRAP_BIT  25   /* (0x040) Page Ref. Trap enable (T bit) */
#define _PAGE_NO_CACHE_BIT 24   /* (0x080) Uncached Page (U bit) */
#define _PAGE_ACCESSED_BIT 23   /* (0x100) Software: Page Accessed */
#define _PAGE_PRESENT_BIT  22   /* (0x200) Software: translation valid */
/* bit 21 was formerly the FLUSH bit but is now unused */
#define _PAGE_USER_BIT     20   /* (0x800) Software: User accessible page */

/* N.B. The bits are defined in terms of a 32 bit word above, so the */
/*      following macro is ok for both 32 and 64 bit.                */

#define xlate_pabit(x) (31 - x)

/* this defines the shift to the usable bits in the PTE it is set so
 * that the valid bits _PAGE_PRESENT_BIT and _PAGE_USER_BIT are set
 * to zero */
#define PTE_SHIFT	   	xlate_pabit(_PAGE_USER_BIT)

/* PFN_PTE_SHIFT defines the shift of a PTE value to access the PFN field */
#define PFN_PTE_SHIFT		12


/* this is how many bits may be used by the file functions */
#define PTE_FILE_MAX_BITS	(BITS_PER_LONG - PTE_SHIFT)

#define pte_to_pgoff(pte) (pte_val(pte) >> PTE_SHIFT)
#define pgoff_to_pte(off) ((pte_t) { ((off) << PTE_SHIFT) | _PAGE_FILE })

#define _PAGE_READ     (1 << xlate_pabit(_PAGE_READ_BIT))
#define _PAGE_WRITE    (1 << xlate_pabit(_PAGE_WRITE_BIT))
#define _PAGE_RW       (_PAGE_READ | _PAGE_WRITE)
#define _PAGE_EXEC     (1 << xlate_pabit(_PAGE_EXEC_BIT))
#define _PAGE_GATEWAY  (1 << xlate_pabit(_PAGE_GATEWAY_BIT))
#define _PAGE_DMB      (1 << xlate_pabit(_PAGE_DMB_BIT))
#define _PAGE_DIRTY    (1 << xlate_pabit(_PAGE_DIRTY_BIT))
#define _PAGE_REFTRAP  (1 << xlate_pabit(_PAGE_REFTRAP_BIT))
#define _PAGE_NO_CACHE (1 << xlate_pabit(_PAGE_NO_CACHE_BIT))
#define _PAGE_ACCESSED (1 << xlate_pabit(_PAGE_ACCESSED_BIT))
#define _PAGE_PRESENT  (1 << xlate_pabit(_PAGE_PRESENT_BIT))
#define _PAGE_USER     (1 << xlate_pabit(_PAGE_USER_BIT))
#define _PAGE_FILE     (1 << xlate_pabit(_PAGE_FILE_BIT))

#define _PAGE_TABLE	(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE |  _PAGE_DIRTY | _PAGE_ACCESSED)
#define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
#define _PAGE_KERNEL_RO	(_PAGE_PRESENT | _PAGE_READ | _PAGE_DIRTY | _PAGE_ACCESSED)
#define _PAGE_KERNEL_EXEC	(_PAGE_KERNEL_RO | _PAGE_EXEC)
#define _PAGE_KERNEL_RWX	(_PAGE_KERNEL_EXEC | _PAGE_WRITE)
#define _PAGE_KERNEL		(_PAGE_KERNEL_RO | _PAGE_WRITE)

/* The pgd/pmd contains a ptr (in phys addr space); since all pgds/pmds
 * are page-aligned, we don't care about the PAGE_OFFSET bits, except
 * for a few meta-information bits, so we shift the address to be
 * able to effectively address 40/42/44-bits of physical address space
 * depending on 4k/16k/64k PAGE_SIZE */
#define _PxD_PRESENT_BIT   31
#define _PxD_ATTACHED_BIT  30
#define _PxD_VALID_BIT     29

#define PxD_FLAG_PRESENT  (1 << xlate_pabit(_PxD_PRESENT_BIT))
#define PxD_FLAG_ATTACHED (1 << xlate_pabit(_PxD_ATTACHED_BIT))
#define PxD_FLAG_VALID    (1 << xlate_pabit(_PxD_VALID_BIT))
#define PxD_FLAG_MASK     (0xf)
#define PxD_FLAG_SHIFT    (4)
#define PxD_VALUE_SHIFT   (8) /* (PAGE_SHIFT-PxD_FLAG_SHIFT) */

#ifndef __ASSEMBLY__

#define PAGE_NONE	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
#define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_ACCESSED)
/* Others seem to make this executable, I don't know if that's correct
   or not.  The stack is mapped this way though so this is necessary
   in the short term - dhd@linuxcare.com, 2000-08-08 */
#define PAGE_READONLY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_ACCESSED)
#define PAGE_WRITEONLY  __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_WRITE | _PAGE_ACCESSED)
#define PAGE_EXECREAD   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_EXEC |_PAGE_ACCESSED)
#define PAGE_COPY       PAGE_EXECREAD
#define PAGE_RWX        __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC |_PAGE_ACCESSED)
#define PAGE_KERNEL	__pgprot(_PAGE_KERNEL)
#define PAGE_KERNEL_EXEC	__pgprot(_PAGE_KERNEL_EXEC)
#define PAGE_KERNEL_RWX	__pgprot(_PAGE_KERNEL_RWX)
#define PAGE_KERNEL_RO	__pgprot(_PAGE_KERNEL_RO)
#define PAGE_KERNEL_UNC	__pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
#define PAGE_GATEWAY    __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED | _PAGE_GATEWAY| _PAGE_READ)


/*
 * We could have an execute only page using "gateway - promote to priv
 * level 3", but that is kind of silly. So, the way things are defined
 * now, we must always have read permission for pages with execute
 * permission. For the fun of it we'll go ahead and support write only
 * pages.
 */

	 /*xwr*/
#define __P000  PAGE_NONE
#define __P001  PAGE_READONLY
#define __P010  __P000 /* copy on write */
#define __P011  __P001 /* copy on write */
#define __P100  PAGE_EXECREAD
#define __P101  PAGE_EXECREAD
#define __P110  __P100 /* copy on write */
#define __P111  __P101 /* copy on write */

#define __S000  PAGE_NONE
#define __S001  PAGE_READONLY
#define __S010  PAGE_WRITEONLY
#define __S011  PAGE_SHARED
#define __S100  PAGE_EXECREAD
#define __S101  PAGE_EXECREAD
#define __S110  PAGE_RWX
#define __S111  PAGE_RWX


extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */

/* initial page tables for 0-8MB for kernel */

extern pte_t pg0[];

/* zero page used for uninitialized stuff */

extern unsigned long *empty_zero_page;

/*
 * ZERO_PAGE is a global shared page that is always zero: used
 * for zero-mapped memory areas etc..
 */

#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))

#define pte_none(x)     (pte_val(x) == 0)
#define pte_present(x)	(pte_val(x) & _PAGE_PRESENT)
#define pte_clear(mm,addr,xp)	do { pte_val(*(xp)) = 0; } while (0)

#define pmd_flag(x)	(pmd_val(x) & PxD_FLAG_MASK)
#define pmd_address(x)	((unsigned long)(pmd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
#define pgd_flag(x)	(pgd_val(x) & PxD_FLAG_MASK)
#define pgd_address(x)	((unsigned long)(pgd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)

#if PT_NLEVELS == 3
/* The first entry of the permanent pmd is not there if it contains
 * the gateway marker */
#define pmd_none(x)	(!pmd_val(x) || pmd_flag(x) == PxD_FLAG_ATTACHED)
#else
#define pmd_none(x)	(!pmd_val(x))
#endif
#define pmd_bad(x)	(!(pmd_flag(x) & PxD_FLAG_VALID))
#define pmd_present(x)	(pmd_flag(x) & PxD_FLAG_PRESENT)
static inline void pmd_clear(pmd_t *pmd) {
#if PT_NLEVELS == 3
	if (pmd_flag(*pmd) & PxD_FLAG_ATTACHED)
		/* This is the entry pointing to the permanent pmd
		 * attached to the pgd; cannot clear it */
		__pmd_val_set(*pmd, PxD_FLAG_ATTACHED);
	else
#endif
		__pmd_val_set(*pmd,  0);
}



#if PT_NLEVELS == 3
#define pgd_page_vaddr(pgd) ((unsigned long) __va(pgd_address(pgd)))
#define pgd_page(pgd)	virt_to_page((void *)pgd_page_vaddr(pgd))

/* For 64 bit we have three level tables */

#define pgd_none(x)     (!pgd_val(x))
#define pgd_bad(x)      (!(pgd_flag(x) & PxD_FLAG_VALID))
#define pgd_present(x)  (pgd_flag(x) & PxD_FLAG_PRESENT)
static inline void pgd_clear(pgd_t *pgd) {
#if PT_NLEVELS == 3
	if(pgd_flag(*pgd) & PxD_FLAG_ATTACHED)
		/* This is the permanent pmd attached to the pgd; cannot
		 * free it */
		return;
#endif
	__pgd_val_set(*pgd, 0);
}
#else
/*
 * The "pgd_xxx()" functions here are trivial for a folded two-level
 * setup: the pgd is never bad, and a pmd always exists (as it's folded
 * into the pgd entry)
 */
static inline int pgd_none(pgd_t pgd)		{ return 0; }
static inline int pgd_bad(pgd_t pgd)		{ return 0; }
static inline int pgd_present(pgd_t pgd)	{ return 1; }
static inline void pgd_clear(pgd_t * pgdp)	{ }
#endif

/*
 * The following only work if pte_present() is true.
 * Undefined behaviour if not..
 */
static inline int pte_dirty(pte_t pte)		{ return pte_val(pte) & _PAGE_DIRTY; }
static inline int pte_young(pte_t pte)		{ return pte_val(pte) & _PAGE_ACCESSED; }
static inline int pte_write(pte_t pte)		{ return pte_val(pte) & _PAGE_WRITE; }
static inline int pte_file(pte_t pte)		{ return pte_val(pte) & _PAGE_FILE; }
static inline int pte_special(pte_t pte)	{ return 0; }

static inline pte_t pte_mkclean(pte_t pte)	{ pte_val(pte) &= ~_PAGE_DIRTY; return pte; }
static inline pte_t pte_mkold(pte_t pte)	{ pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
static inline pte_t pte_wrprotect(pte_t pte)	{ pte_val(pte) &= ~_PAGE_WRITE; return pte; }
static inline pte_t pte_mkdirty(pte_t pte)	{ pte_val(pte) |= _PAGE_DIRTY; return pte; }
static inline pte_t pte_mkyoung(pte_t pte)	{ pte_val(pte) |= _PAGE_ACCESSED; return pte; }
static inline pte_t pte_mkwrite(pte_t pte)	{ pte_val(pte) |= _PAGE_WRITE; return pte; }
static inline pte_t pte_mkspecial(pte_t pte)	{ return pte; }

/*
 * Conversion functions: convert a page and protection to a page entry,
 * and a page entry and page directory to the page they refer to.
 */
#define __mk_pte(addr,pgprot) \
({									\
	pte_t __pte;							\
									\
	pte_val(__pte) = ((((addr)>>PAGE_SHIFT)<<PFN_PTE_SHIFT) + pgprot_val(pgprot));	\
									\
	__pte;								\
})

#define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))

static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
{
	pte_t pte;
	pte_val(pte) = (pfn << PFN_PTE_SHIFT) | pgprot_val(pgprot);
	return pte;
}

static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{ pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); return pte; }

/* Permanent address of a page.  On parisc we don't have highmem. */

#define pte_pfn(x)		(pte_val(x) >> PFN_PTE_SHIFT)

#define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))

#define pmd_page_vaddr(pmd)	((unsigned long) __va(pmd_address(pmd)))

#define __pmd_page(pmd) ((unsigned long) __va(pmd_address(pmd)))
#define pmd_page(pmd)	virt_to_page((void *)__pmd_page(pmd))

#define pgd_index(address) ((address) >> PGDIR_SHIFT)

/* to find an entry in a page-table-directory */
#define pgd_offset(mm, address) \
((mm)->pgd + ((address) >> PGDIR_SHIFT))

/* to find an entry in a kernel page-table-directory */
#define pgd_offset_k(address) pgd_offset(&init_mm, address)

/* Find an entry in the second-level page table.. */

#if PT_NLEVELS == 3
#define pmd_offset(dir,address) \
((pmd_t *) pgd_page_vaddr(*(dir)) + (((address)>>PMD_SHIFT) & (PTRS_PER_PMD-1)))
#else
#define pmd_offset(dir,addr) ((pmd_t *) dir)
#endif

/* Find an entry in the third-level page table.. */ 
#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
#define pte_offset_kernel(pmd, address) \
	((pte_t *) pmd_page_vaddr(*(pmd)) + pte_index(address))
#define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address)
#define pte_unmap(pte) do { } while (0)

#define pte_unmap(pte)			do { } while (0)
#define pte_unmap_nested(pte)		do { } while (0)

extern void paging_init (void);

/* Used for deferring calls to flush_dcache_page() */

#define PG_dcache_dirty         PG_arch_1

extern void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t *);

/* Encode and de-code a swap entry */

#define __swp_type(x)                     ((x).val & 0x1f)
#define __swp_offset(x)                   ( (((x).val >> 6) &  0x7) | \
					  (((x).val >> 8) & ~0x7) )
#define __swp_entry(type, offset)         ((swp_entry_t) { (type) | \
					    ((offset &  0x7) << 6) | \
					    ((offset & ~0x7) << 8) })
#define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
#define __swp_entry_to_pte(x)		((pte_t) { (x).val })

static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
{
	pte_t pte;
	unsigned long flags;

	if (!pte_young(*ptep))
		return 0;

	spin_lock_irqsave(&pa_dbit_lock, flags);
	pte = *ptep;
	if (!pte_young(pte)) {
		spin_unlock_irqrestore(&pa_dbit_lock, flags);
		return 0;
	}
	set_pte(ptep, pte_mkold(pte));
	purge_tlb_entries(vma->vm_mm, addr);
	spin_unlock_irqrestore(&pa_dbit_lock, flags);
	return 1;
}

struct mm_struct;
static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
	pte_t old_pte;
	unsigned long flags;

	spin_lock_irqsave(&pa_dbit_lock, flags);
	old_pte = *ptep;
	pte_clear(mm,addr,ptep);
	purge_tlb_entries(mm, addr);
	spin_unlock_irqrestore(&pa_dbit_lock, flags);

	return old_pte;
}

static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
	unsigned long flags;
	spin_lock_irqsave(&pa_dbit_lock, flags);
	set_pte(ptep, pte_wrprotect(*ptep));
	purge_tlb_entries(mm, addr);
	spin_unlock_irqrestore(&pa_dbit_lock, flags);
}

#define pte_same(A,B)	(pte_val(A) == pte_val(B))

#endif /* !__ASSEMBLY__ */


/* TLB page size encoding - see table 3-1 in parisc20.pdf */
#define _PAGE_SIZE_ENCODING_4K		0
#define _PAGE_SIZE_ENCODING_16K		1
#define _PAGE_SIZE_ENCODING_64K		2
#define _PAGE_SIZE_ENCODING_256K	3
#define _PAGE_SIZE_ENCODING_1M		4
#define _PAGE_SIZE_ENCODING_4M		5
#define _PAGE_SIZE_ENCODING_16M		6
#define _PAGE_SIZE_ENCODING_64M		7

#if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_4K
#elif defined(CONFIG_PARISC_PAGE_SIZE_16KB)
# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_16K
#elif defined(CONFIG_PARISC_PAGE_SIZE_64KB)
# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_64K
#endif


#define pgprot_noncached(prot) __pgprot(pgprot_val(prot) | _PAGE_NO_CACHE)

/* We provide our own get_unmapped_area to provide cache coherency */

#define HAVE_ARCH_UNMAPPED_AREA
#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN

#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
#define __HAVE_ARCH_PTEP_SET_WRPROTECT
#define __HAVE_ARCH_PTE_SAME
#include <asm-generic/pgtable.h>

#endif /* _PARISC_PGTABLE_H */