xref: /openbmc/linux/arch/parisc/include/asm/pgtable.h (revision 2c684d89)
1 #ifndef _PARISC_PGTABLE_H
2 #define _PARISC_PGTABLE_H
3 
4 #include <asm-generic/4level-fixup.h>
5 
6 #include <asm/fixmap.h>
7 
8 #ifndef __ASSEMBLY__
9 /*
10  * we simulate an x86-style page table for the linux mm code
11  */
12 
13 #include <linux/bitops.h>
14 #include <linux/spinlock.h>
15 #include <linux/mm_types.h>
16 #include <asm/processor.h>
17 #include <asm/cache.h>
18 
19 extern spinlock_t pa_tlb_lock;
20 
21 /*
22  * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
23  * memory.  For the return value to be meaningful, ADDR must be >=
24  * PAGE_OFFSET.  This operation can be relatively expensive (e.g.,
25  * require a hash-, or multi-level tree-lookup or something of that
26  * sort) but it guarantees to return TRUE only if accessing the page
27  * at that address does not cause an error.  Note that there may be
28  * addresses for which kern_addr_valid() returns FALSE even though an
29  * access would not cause an error (e.g., this is typically true for
30  * memory mapped I/O regions.
31  *
32  * XXX Need to implement this for parisc.
33  */
34 #define kern_addr_valid(addr)	(1)
35 
36 /* Purge data and instruction TLB entries.  Must be called holding
37  * the pa_tlb_lock.  The TLB purge instructions are slow on SMP
38  * machines since the purge must be broadcast to all CPUs.
39  */
40 
41 static inline void purge_tlb_entries(struct mm_struct *mm, unsigned long addr)
42 {
43 	mtsp(mm->context, 1);
44 	pdtlb(addr);
45 	if (unlikely(split_tlb))
46 		pitlb(addr);
47 }
48 
49 /* Certain architectures need to do special things when PTEs
50  * within a page table are directly modified.  Thus, the following
51  * hook is made available.
52  */
53 #define set_pte(pteptr, pteval)                                 \
54         do{                                                     \
55                 *(pteptr) = (pteval);                           \
56         } while(0)
57 
58 #define pte_inserted(x)						\
59 	((pte_val(x) & (_PAGE_PRESENT|_PAGE_ACCESSED))		\
60 	 == (_PAGE_PRESENT|_PAGE_ACCESSED))
61 
62 #define set_pte_at(mm, addr, ptep, pteval)			\
63 	do {							\
64 		pte_t old_pte;					\
65 		unsigned long flags;				\
66 		spin_lock_irqsave(&pa_tlb_lock, flags);		\
67 		old_pte = *ptep;				\
68 		set_pte(ptep, pteval);				\
69 		if (pte_inserted(old_pte))			\
70 			purge_tlb_entries(mm, addr);		\
71 		spin_unlock_irqrestore(&pa_tlb_lock, flags);	\
72 	} while (0)
73 
74 #endif /* !__ASSEMBLY__ */
75 
76 #include <asm/page.h>
77 
78 #define pte_ERROR(e) \
79 	printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
80 #define pmd_ERROR(e) \
81 	printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, (unsigned long)pmd_val(e))
82 #define pgd_ERROR(e) \
83 	printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, (unsigned long)pgd_val(e))
84 
85 /* This is the size of the initially mapped kernel memory */
86 #ifdef CONFIG_64BIT
87 #define KERNEL_INITIAL_ORDER	25	/* 1<<25 = 32MB */
88 #else
89 #define KERNEL_INITIAL_ORDER	24	/* 1<<24 = 16MB */
90 #endif
91 #define KERNEL_INITIAL_SIZE	(1 << KERNEL_INITIAL_ORDER)
92 
93 #if CONFIG_PGTABLE_LEVELS == 3
94 #define PGD_ORDER	1 /* Number of pages per pgd */
95 #define PMD_ORDER	1 /* Number of pages per pmd */
96 #define PGD_ALLOC_ORDER	2 /* first pgd contains pmd */
97 #else
98 #define PGD_ORDER	1 /* Number of pages per pgd */
99 #define PGD_ALLOC_ORDER	PGD_ORDER
100 #endif
101 
102 /* Definitions for 3rd level (we use PLD here for Page Lower directory
103  * because PTE_SHIFT is used lower down to mean shift that has to be
104  * done to get usable bits out of the PTE) */
105 #define PLD_SHIFT	PAGE_SHIFT
106 #define PLD_SIZE	PAGE_SIZE
107 #define BITS_PER_PTE	(PAGE_SHIFT - BITS_PER_PTE_ENTRY)
108 #define PTRS_PER_PTE    (1UL << BITS_PER_PTE)
109 
110 /* Definitions for 2nd level */
111 #define pgtable_cache_init()	do { } while (0)
112 
113 #define PMD_SHIFT       (PLD_SHIFT + BITS_PER_PTE)
114 #define PMD_SIZE	(1UL << PMD_SHIFT)
115 #define PMD_MASK	(~(PMD_SIZE-1))
116 #if CONFIG_PGTABLE_LEVELS == 3
117 #define BITS_PER_PMD	(PAGE_SHIFT + PMD_ORDER - BITS_PER_PMD_ENTRY)
118 #else
119 #define __PAGETABLE_PMD_FOLDED
120 #define BITS_PER_PMD	0
121 #endif
122 #define PTRS_PER_PMD    (1UL << BITS_PER_PMD)
123 
124 /* Definitions for 1st level */
125 #define PGDIR_SHIFT	(PMD_SHIFT + BITS_PER_PMD)
126 #if (PGDIR_SHIFT + PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY) > BITS_PER_LONG
127 #define BITS_PER_PGD	(BITS_PER_LONG - PGDIR_SHIFT)
128 #else
129 #define BITS_PER_PGD	(PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY)
130 #endif
131 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
132 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
133 #define PTRS_PER_PGD    (1UL << BITS_PER_PGD)
134 #define USER_PTRS_PER_PGD       PTRS_PER_PGD
135 
136 #ifdef CONFIG_64BIT
137 #define MAX_ADDRBITS	(PGDIR_SHIFT + BITS_PER_PGD)
138 #define MAX_ADDRESS	(1UL << MAX_ADDRBITS)
139 #define SPACEID_SHIFT	(MAX_ADDRBITS - 32)
140 #else
141 #define MAX_ADDRBITS	(BITS_PER_LONG)
142 #define MAX_ADDRESS	(1UL << MAX_ADDRBITS)
143 #define SPACEID_SHIFT	0
144 #endif
145 
146 /* This calculates the number of initial pages we need for the initial
147  * page tables */
148 #if (KERNEL_INITIAL_ORDER) >= (PMD_SHIFT)
149 # define PT_INITIAL	(1 << (KERNEL_INITIAL_ORDER - PMD_SHIFT))
150 #else
151 # define PT_INITIAL	(1)  /* all initial PTEs fit into one page */
152 #endif
153 
154 /*
155  * pgd entries used up by user/kernel:
156  */
157 
158 #define FIRST_USER_ADDRESS	0UL
159 
160 /* NB: The tlb miss handlers make certain assumptions about the order */
161 /*     of the following bits, so be careful (One example, bits 25-31  */
162 /*     are moved together in one instruction).                        */
163 
164 #define _PAGE_READ_BIT     31   /* (0x001) read access allowed */
165 #define _PAGE_WRITE_BIT    30   /* (0x002) write access allowed */
166 #define _PAGE_EXEC_BIT     29   /* (0x004) execute access allowed */
167 #define _PAGE_GATEWAY_BIT  28   /* (0x008) privilege promotion allowed */
168 #define _PAGE_DMB_BIT      27   /* (0x010) Data Memory Break enable (B bit) */
169 #define _PAGE_DIRTY_BIT    26   /* (0x020) Page Dirty (D bit) */
170 #define _PAGE_REFTRAP_BIT  25   /* (0x040) Page Ref. Trap enable (T bit) */
171 #define _PAGE_NO_CACHE_BIT 24   /* (0x080) Uncached Page (U bit) */
172 #define _PAGE_ACCESSED_BIT 23   /* (0x100) Software: Page Accessed */
173 #define _PAGE_PRESENT_BIT  22   /* (0x200) Software: translation valid */
174 #define _PAGE_HPAGE_BIT    21   /* (0x400) Software: Huge Page */
175 #define _PAGE_USER_BIT     20   /* (0x800) Software: User accessible page */
176 
177 /* N.B. The bits are defined in terms of a 32 bit word above, so the */
178 /*      following macro is ok for both 32 and 64 bit.                */
179 
180 #define xlate_pabit(x) (31 - x)
181 
182 /* this defines the shift to the usable bits in the PTE it is set so
183  * that the valid bits _PAGE_PRESENT_BIT and _PAGE_USER_BIT are set
184  * to zero */
185 #define PTE_SHIFT	   	xlate_pabit(_PAGE_USER_BIT)
186 
187 /* PFN_PTE_SHIFT defines the shift of a PTE value to access the PFN field */
188 #define PFN_PTE_SHIFT		12
189 
190 #define _PAGE_READ     (1 << xlate_pabit(_PAGE_READ_BIT))
191 #define _PAGE_WRITE    (1 << xlate_pabit(_PAGE_WRITE_BIT))
192 #define _PAGE_RW       (_PAGE_READ | _PAGE_WRITE)
193 #define _PAGE_EXEC     (1 << xlate_pabit(_PAGE_EXEC_BIT))
194 #define _PAGE_GATEWAY  (1 << xlate_pabit(_PAGE_GATEWAY_BIT))
195 #define _PAGE_DMB      (1 << xlate_pabit(_PAGE_DMB_BIT))
196 #define _PAGE_DIRTY    (1 << xlate_pabit(_PAGE_DIRTY_BIT))
197 #define _PAGE_REFTRAP  (1 << xlate_pabit(_PAGE_REFTRAP_BIT))
198 #define _PAGE_NO_CACHE (1 << xlate_pabit(_PAGE_NO_CACHE_BIT))
199 #define _PAGE_ACCESSED (1 << xlate_pabit(_PAGE_ACCESSED_BIT))
200 #define _PAGE_PRESENT  (1 << xlate_pabit(_PAGE_PRESENT_BIT))
201 #define _PAGE_HUGE     (1 << xlate_pabit(_PAGE_HPAGE_BIT))
202 #define _PAGE_USER     (1 << xlate_pabit(_PAGE_USER_BIT))
203 
204 #define _PAGE_TABLE	(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE |  _PAGE_DIRTY | _PAGE_ACCESSED)
205 #define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
206 #define _PAGE_KERNEL_RO	(_PAGE_PRESENT | _PAGE_READ | _PAGE_DIRTY | _PAGE_ACCESSED)
207 #define _PAGE_KERNEL_EXEC	(_PAGE_KERNEL_RO | _PAGE_EXEC)
208 #define _PAGE_KERNEL_RWX	(_PAGE_KERNEL_EXEC | _PAGE_WRITE)
209 #define _PAGE_KERNEL		(_PAGE_KERNEL_RO | _PAGE_WRITE)
210 
211 /* The pgd/pmd contains a ptr (in phys addr space); since all pgds/pmds
212  * are page-aligned, we don't care about the PAGE_OFFSET bits, except
213  * for a few meta-information bits, so we shift the address to be
214  * able to effectively address 40/42/44-bits of physical address space
215  * depending on 4k/16k/64k PAGE_SIZE */
216 #define _PxD_PRESENT_BIT   31
217 #define _PxD_ATTACHED_BIT  30
218 #define _PxD_VALID_BIT     29
219 
220 #define PxD_FLAG_PRESENT  (1 << xlate_pabit(_PxD_PRESENT_BIT))
221 #define PxD_FLAG_ATTACHED (1 << xlate_pabit(_PxD_ATTACHED_BIT))
222 #define PxD_FLAG_VALID    (1 << xlate_pabit(_PxD_VALID_BIT))
223 #define PxD_FLAG_MASK     (0xf)
224 #define PxD_FLAG_SHIFT    (4)
225 #define PxD_VALUE_SHIFT   (PFN_PTE_SHIFT-PxD_FLAG_SHIFT)
226 
227 #ifndef __ASSEMBLY__
228 
229 #define PAGE_NONE	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
230 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_ACCESSED)
231 /* Others seem to make this executable, I don't know if that's correct
232    or not.  The stack is mapped this way though so this is necessary
233    in the short term - dhd@linuxcare.com, 2000-08-08 */
234 #define PAGE_READONLY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_ACCESSED)
235 #define PAGE_WRITEONLY  __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_WRITE | _PAGE_ACCESSED)
236 #define PAGE_EXECREAD   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_EXEC |_PAGE_ACCESSED)
237 #define PAGE_COPY       PAGE_EXECREAD
238 #define PAGE_RWX        __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC |_PAGE_ACCESSED)
239 #define PAGE_KERNEL	__pgprot(_PAGE_KERNEL)
240 #define PAGE_KERNEL_EXEC	__pgprot(_PAGE_KERNEL_EXEC)
241 #define PAGE_KERNEL_RWX	__pgprot(_PAGE_KERNEL_RWX)
242 #define PAGE_KERNEL_RO	__pgprot(_PAGE_KERNEL_RO)
243 #define PAGE_KERNEL_UNC	__pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
244 #define PAGE_GATEWAY    __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED | _PAGE_GATEWAY| _PAGE_READ)
245 
246 
247 /*
248  * We could have an execute only page using "gateway - promote to priv
249  * level 3", but that is kind of silly. So, the way things are defined
250  * now, we must always have read permission for pages with execute
251  * permission. For the fun of it we'll go ahead and support write only
252  * pages.
253  */
254 
255 	 /*xwr*/
256 #define __P000  PAGE_NONE
257 #define __P001  PAGE_READONLY
258 #define __P010  __P000 /* copy on write */
259 #define __P011  __P001 /* copy on write */
260 #define __P100  PAGE_EXECREAD
261 #define __P101  PAGE_EXECREAD
262 #define __P110  __P100 /* copy on write */
263 #define __P111  __P101 /* copy on write */
264 
265 #define __S000  PAGE_NONE
266 #define __S001  PAGE_READONLY
267 #define __S010  PAGE_WRITEONLY
268 #define __S011  PAGE_SHARED
269 #define __S100  PAGE_EXECREAD
270 #define __S101  PAGE_EXECREAD
271 #define __S110  PAGE_RWX
272 #define __S111  PAGE_RWX
273 
274 
275 extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */
276 
277 /* initial page tables for 0-8MB for kernel */
278 
279 extern pte_t pg0[];
280 
281 /* zero page used for uninitialized stuff */
282 
283 extern unsigned long *empty_zero_page;
284 
285 /*
286  * ZERO_PAGE is a global shared page that is always zero: used
287  * for zero-mapped memory areas etc..
288  */
289 
290 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
291 
292 #define pte_none(x)     (pte_val(x) == 0)
293 #define pte_present(x)	(pte_val(x) & _PAGE_PRESENT)
294 #define pte_clear(mm, addr, xp)  set_pte_at(mm, addr, xp, __pte(0))
295 
296 #define pmd_flag(x)	(pmd_val(x) & PxD_FLAG_MASK)
297 #define pmd_address(x)	((unsigned long)(pmd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
298 #define pgd_flag(x)	(pgd_val(x) & PxD_FLAG_MASK)
299 #define pgd_address(x)	((unsigned long)(pgd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
300 
301 #if CONFIG_PGTABLE_LEVELS == 3
302 /* The first entry of the permanent pmd is not there if it contains
303  * the gateway marker */
304 #define pmd_none(x)	(!pmd_val(x) || pmd_flag(x) == PxD_FLAG_ATTACHED)
305 #else
306 #define pmd_none(x)	(!pmd_val(x))
307 #endif
308 #define pmd_bad(x)	(!(pmd_flag(x) & PxD_FLAG_VALID))
309 #define pmd_present(x)	(pmd_flag(x) & PxD_FLAG_PRESENT)
310 static inline void pmd_clear(pmd_t *pmd) {
311 #if CONFIG_PGTABLE_LEVELS == 3
312 	if (pmd_flag(*pmd) & PxD_FLAG_ATTACHED)
313 		/* This is the entry pointing to the permanent pmd
314 		 * attached to the pgd; cannot clear it */
315 		__pmd_val_set(*pmd, PxD_FLAG_ATTACHED);
316 	else
317 #endif
318 		__pmd_val_set(*pmd,  0);
319 }
320 
321 
322 
323 #if CONFIG_PGTABLE_LEVELS == 3
324 #define pgd_page_vaddr(pgd) ((unsigned long) __va(pgd_address(pgd)))
325 #define pgd_page(pgd)	virt_to_page((void *)pgd_page_vaddr(pgd))
326 
327 /* For 64 bit we have three level tables */
328 
329 #define pgd_none(x)     (!pgd_val(x))
330 #define pgd_bad(x)      (!(pgd_flag(x) & PxD_FLAG_VALID))
331 #define pgd_present(x)  (pgd_flag(x) & PxD_FLAG_PRESENT)
332 static inline void pgd_clear(pgd_t *pgd) {
333 #if CONFIG_PGTABLE_LEVELS == 3
334 	if(pgd_flag(*pgd) & PxD_FLAG_ATTACHED)
335 		/* This is the permanent pmd attached to the pgd; cannot
336 		 * free it */
337 		return;
338 #endif
339 	__pgd_val_set(*pgd, 0);
340 }
341 #else
342 /*
343  * The "pgd_xxx()" functions here are trivial for a folded two-level
344  * setup: the pgd is never bad, and a pmd always exists (as it's folded
345  * into the pgd entry)
346  */
347 static inline int pgd_none(pgd_t pgd)		{ return 0; }
348 static inline int pgd_bad(pgd_t pgd)		{ return 0; }
349 static inline int pgd_present(pgd_t pgd)	{ return 1; }
350 static inline void pgd_clear(pgd_t * pgdp)	{ }
351 #endif
352 
353 /*
354  * The following only work if pte_present() is true.
355  * Undefined behaviour if not..
356  */
357 static inline int pte_dirty(pte_t pte)		{ return pte_val(pte) & _PAGE_DIRTY; }
358 static inline int pte_young(pte_t pte)		{ return pte_val(pte) & _PAGE_ACCESSED; }
359 static inline int pte_write(pte_t pte)		{ return pte_val(pte) & _PAGE_WRITE; }
360 static inline int pte_special(pte_t pte)	{ return 0; }
361 
362 static inline pte_t pte_mkclean(pte_t pte)	{ pte_val(pte) &= ~_PAGE_DIRTY; return pte; }
363 static inline pte_t pte_mkold(pte_t pte)	{ pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
364 static inline pte_t pte_wrprotect(pte_t pte)	{ pte_val(pte) &= ~_PAGE_WRITE; return pte; }
365 static inline pte_t pte_mkdirty(pte_t pte)	{ pte_val(pte) |= _PAGE_DIRTY; return pte; }
366 static inline pte_t pte_mkyoung(pte_t pte)	{ pte_val(pte) |= _PAGE_ACCESSED; return pte; }
367 static inline pte_t pte_mkwrite(pte_t pte)	{ pte_val(pte) |= _PAGE_WRITE; return pte; }
368 static inline pte_t pte_mkspecial(pte_t pte)	{ return pte; }
369 
370 /*
371  * Huge pte definitions.
372  */
373 #ifdef CONFIG_HUGETLB_PAGE
374 #define pte_huge(pte)           (pte_val(pte) & _PAGE_HUGE)
375 #define pte_mkhuge(pte)         (__pte(pte_val(pte) | \
376 				 (parisc_requires_coherency() ? 0 : _PAGE_HUGE)))
377 #else
378 #define pte_huge(pte)           (0)
379 #define pte_mkhuge(pte)         (pte)
380 #endif
381 
382 
383 /*
384  * Conversion functions: convert a page and protection to a page entry,
385  * and a page entry and page directory to the page they refer to.
386  */
387 #define __mk_pte(addr,pgprot) \
388 ({									\
389 	pte_t __pte;							\
390 									\
391 	pte_val(__pte) = ((((addr)>>PAGE_SHIFT)<<PFN_PTE_SHIFT) + pgprot_val(pgprot));	\
392 									\
393 	__pte;								\
394 })
395 
396 #define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))
397 
398 static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
399 {
400 	pte_t pte;
401 	pte_val(pte) = (pfn << PFN_PTE_SHIFT) | pgprot_val(pgprot);
402 	return pte;
403 }
404 
405 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
406 { pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); return pte; }
407 
408 /* Permanent address of a page.  On parisc we don't have highmem. */
409 
410 #define pte_pfn(x)		(pte_val(x) >> PFN_PTE_SHIFT)
411 
412 #define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
413 
414 #define pmd_page_vaddr(pmd)	((unsigned long) __va(pmd_address(pmd)))
415 
416 #define __pmd_page(pmd) ((unsigned long) __va(pmd_address(pmd)))
417 #define pmd_page(pmd)	virt_to_page((void *)__pmd_page(pmd))
418 
419 #define pgd_index(address) ((address) >> PGDIR_SHIFT)
420 
421 /* to find an entry in a page-table-directory */
422 #define pgd_offset(mm, address) \
423 ((mm)->pgd + ((address) >> PGDIR_SHIFT))
424 
425 /* to find an entry in a kernel page-table-directory */
426 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
427 
428 /* Find an entry in the second-level page table.. */
429 
430 #if CONFIG_PGTABLE_LEVELS == 3
431 #define pmd_index(addr)         (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
432 #define pmd_offset(dir,address) \
433 ((pmd_t *) pgd_page_vaddr(*(dir)) + pmd_index(address))
434 #else
435 #define pmd_offset(dir,addr) ((pmd_t *) dir)
436 #endif
437 
438 /* Find an entry in the third-level page table.. */
439 #define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
440 #define pte_offset_kernel(pmd, address) \
441 	((pte_t *) pmd_page_vaddr(*(pmd)) + pte_index(address))
442 #define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address)
443 #define pte_unmap(pte) do { } while (0)
444 
445 #define pte_unmap(pte)			do { } while (0)
446 #define pte_unmap_nested(pte)		do { } while (0)
447 
448 extern void paging_init (void);
449 
450 /* Used for deferring calls to flush_dcache_page() */
451 
452 #define PG_dcache_dirty         PG_arch_1
453 
454 extern void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t *);
455 
456 /* Encode and de-code a swap entry */
457 
458 #define __swp_type(x)                     ((x).val & 0x1f)
459 #define __swp_offset(x)                   ( (((x).val >> 6) &  0x7) | \
460 					  (((x).val >> 8) & ~0x7) )
461 #define __swp_entry(type, offset)         ((swp_entry_t) { (type) | \
462 					    ((offset &  0x7) << 6) | \
463 					    ((offset & ~0x7) << 8) })
464 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
465 #define __swp_entry_to_pte(x)		((pte_t) { (x).val })
466 
467 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
468 {
469 	pte_t pte;
470 	unsigned long flags;
471 
472 	if (!pte_young(*ptep))
473 		return 0;
474 
475 	spin_lock_irqsave(&pa_tlb_lock, flags);
476 	pte = *ptep;
477 	if (!pte_young(pte)) {
478 		spin_unlock_irqrestore(&pa_tlb_lock, flags);
479 		return 0;
480 	}
481 	set_pte(ptep, pte_mkold(pte));
482 	purge_tlb_entries(vma->vm_mm, addr);
483 	spin_unlock_irqrestore(&pa_tlb_lock, flags);
484 	return 1;
485 }
486 
487 struct mm_struct;
488 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
489 {
490 	pte_t old_pte;
491 	unsigned long flags;
492 
493 	spin_lock_irqsave(&pa_tlb_lock, flags);
494 	old_pte = *ptep;
495 	set_pte(ptep, __pte(0));
496 	if (pte_inserted(old_pte))
497 		purge_tlb_entries(mm, addr);
498 	spin_unlock_irqrestore(&pa_tlb_lock, flags);
499 
500 	return old_pte;
501 }
502 
503 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
504 {
505 	unsigned long flags;
506 	spin_lock_irqsave(&pa_tlb_lock, flags);
507 	set_pte(ptep, pte_wrprotect(*ptep));
508 	purge_tlb_entries(mm, addr);
509 	spin_unlock_irqrestore(&pa_tlb_lock, flags);
510 }
511 
512 #define pte_same(A,B)	(pte_val(A) == pte_val(B))
513 
514 #endif /* !__ASSEMBLY__ */
515 
516 
517 /* TLB page size encoding - see table 3-1 in parisc20.pdf */
518 #define _PAGE_SIZE_ENCODING_4K		0
519 #define _PAGE_SIZE_ENCODING_16K		1
520 #define _PAGE_SIZE_ENCODING_64K		2
521 #define _PAGE_SIZE_ENCODING_256K	3
522 #define _PAGE_SIZE_ENCODING_1M		4
523 #define _PAGE_SIZE_ENCODING_4M		5
524 #define _PAGE_SIZE_ENCODING_16M		6
525 #define _PAGE_SIZE_ENCODING_64M		7
526 
527 #if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
528 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_4K
529 #elif defined(CONFIG_PARISC_PAGE_SIZE_16KB)
530 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_16K
531 #elif defined(CONFIG_PARISC_PAGE_SIZE_64KB)
532 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_64K
533 #endif
534 
535 
536 #define pgprot_noncached(prot) __pgprot(pgprot_val(prot) | _PAGE_NO_CACHE)
537 
538 /* We provide our own get_unmapped_area to provide cache coherency */
539 
540 #define HAVE_ARCH_UNMAPPED_AREA
541 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
542 
543 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
544 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
545 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
546 #define __HAVE_ARCH_PTE_SAME
547 #include <asm-generic/pgtable.h>
548 
549 #endif /* _PARISC_PGTABLE_H */
550