xref: /openbmc/linux/arch/parisc/include/asm/pgtable.h (revision b9df3997)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _PARISC_PGTABLE_H
3 #define _PARISC_PGTABLE_H
4 
5 #include <asm/page.h>
6 #include <asm-generic/4level-fixup.h>
7 
8 #include <asm/fixmap.h>
9 
10 #ifndef __ASSEMBLY__
11 /*
12  * we simulate an x86-style page table for the linux mm code
13  */
14 
15 #include <linux/bitops.h>
16 #include <linux/spinlock.h>
17 #include <linux/mm_types.h>
18 #include <asm/processor.h>
19 #include <asm/cache.h>
20 
21 static inline spinlock_t *pgd_spinlock(pgd_t *);
22 
23 /*
24  * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
25  * memory.  For the return value to be meaningful, ADDR must be >=
26  * PAGE_OFFSET.  This operation can be relatively expensive (e.g.,
27  * require a hash-, or multi-level tree-lookup or something of that
28  * sort) but it guarantees to return TRUE only if accessing the page
29  * at that address does not cause an error.  Note that there may be
30  * addresses for which kern_addr_valid() returns FALSE even though an
31  * access would not cause an error (e.g., this is typically true for
32  * memory mapped I/O regions.
33  *
34  * XXX Need to implement this for parisc.
35  */
36 #define kern_addr_valid(addr)	(1)
37 
38 /* This is for the serialization of PxTLB broadcasts. At least on the N class
39  * systems, only one PxTLB inter processor broadcast can be active at any one
40  * time on the Merced bus.
41 
42  * PTE updates are protected by locks in the PMD.
43  */
44 extern spinlock_t pa_tlb_flush_lock;
45 extern spinlock_t pa_swapper_pg_lock;
46 #if defined(CONFIG_64BIT) && defined(CONFIG_SMP)
47 extern int pa_serialize_tlb_flushes;
48 #else
49 #define pa_serialize_tlb_flushes        (0)
50 #endif
51 
52 #define purge_tlb_start(flags)  do { \
53 	if (pa_serialize_tlb_flushes)	\
54 		spin_lock_irqsave(&pa_tlb_flush_lock, flags); \
55 	else \
56 		local_irq_save(flags);	\
57 	} while (0)
58 #define purge_tlb_end(flags)	do { \
59 	if (pa_serialize_tlb_flushes)	\
60 		spin_unlock_irqrestore(&pa_tlb_flush_lock, flags); \
61 	else \
62 		local_irq_restore(flags); \
63 	} while (0)
64 
65 /* Purge data and instruction TLB entries. The TLB purge instructions
66  * are slow on SMP machines since the purge must be broadcast to all CPUs.
67  */
68 
69 static inline void purge_tlb_entries(struct mm_struct *mm, unsigned long addr)
70 {
71 	unsigned long flags;
72 
73 	purge_tlb_start(flags);
74 	mtsp(mm->context, 1);
75 	pdtlb(addr);
76 	pitlb(addr);
77 	purge_tlb_end(flags);
78 }
79 
80 /* Certain architectures need to do special things when PTEs
81  * within a page table are directly modified.  Thus, the following
82  * hook is made available.
83  */
84 #define set_pte(pteptr, pteval)                                 \
85         do{                                                     \
86                 *(pteptr) = (pteval);                           \
87         } while(0)
88 
89 #define set_pte_at(mm, addr, ptep, pteval)			\
90 	do {							\
91 		pte_t old_pte;					\
92 		unsigned long flags;				\
93 		spin_lock_irqsave(pgd_spinlock((mm)->pgd), flags);\
94 		old_pte = *ptep;				\
95 		set_pte(ptep, pteval);				\
96 		purge_tlb_entries(mm, addr);			\
97 		spin_unlock_irqrestore(pgd_spinlock((mm)->pgd), flags);\
98 	} while (0)
99 
100 #endif /* !__ASSEMBLY__ */
101 
102 #define pte_ERROR(e) \
103 	printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
104 #define pmd_ERROR(e) \
105 	printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, (unsigned long)pmd_val(e))
106 #define pgd_ERROR(e) \
107 	printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, (unsigned long)pgd_val(e))
108 
109 /* This is the size of the initially mapped kernel memory */
110 #if defined(CONFIG_64BIT)
111 #define KERNEL_INITIAL_ORDER	26	/* 1<<26 = 64MB */
112 #else
113 #define KERNEL_INITIAL_ORDER	25	/* 1<<25 = 32MB */
114 #endif
115 #define KERNEL_INITIAL_SIZE	(1 << KERNEL_INITIAL_ORDER)
116 
117 #if CONFIG_PGTABLE_LEVELS == 3
118 #define PGD_ORDER	1 /* Number of pages per pgd */
119 #define PMD_ORDER	1 /* Number of pages per pmd */
120 #define PGD_ALLOC_ORDER	(2 + 1) /* first pgd contains pmd */
121 #else
122 #define PGD_ORDER	1 /* Number of pages per pgd */
123 #define PGD_ALLOC_ORDER	(PGD_ORDER + 1)
124 #endif
125 
126 /* Definitions for 3rd level (we use PLD here for Page Lower directory
127  * because PTE_SHIFT is used lower down to mean shift that has to be
128  * done to get usable bits out of the PTE) */
129 #define PLD_SHIFT	PAGE_SHIFT
130 #define PLD_SIZE	PAGE_SIZE
131 #define BITS_PER_PTE	(PAGE_SHIFT - BITS_PER_PTE_ENTRY)
132 #define PTRS_PER_PTE    (1UL << BITS_PER_PTE)
133 
134 /* Definitions for 2nd level */
135 #define PMD_SHIFT       (PLD_SHIFT + BITS_PER_PTE)
136 #define PMD_SIZE	(1UL << PMD_SHIFT)
137 #define PMD_MASK	(~(PMD_SIZE-1))
138 #if CONFIG_PGTABLE_LEVELS == 3
139 #define BITS_PER_PMD	(PAGE_SHIFT + PMD_ORDER - BITS_PER_PMD_ENTRY)
140 #else
141 #define __PAGETABLE_PMD_FOLDED 1
142 #define BITS_PER_PMD	0
143 #endif
144 #define PTRS_PER_PMD    (1UL << BITS_PER_PMD)
145 
146 /* Definitions for 1st level */
147 #define PGDIR_SHIFT	(PMD_SHIFT + BITS_PER_PMD)
148 #if (PGDIR_SHIFT + PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY) > BITS_PER_LONG
149 #define BITS_PER_PGD	(BITS_PER_LONG - PGDIR_SHIFT)
150 #else
151 #define BITS_PER_PGD	(PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY)
152 #endif
153 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
154 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
155 #define PTRS_PER_PGD    (1UL << BITS_PER_PGD)
156 #define USER_PTRS_PER_PGD       PTRS_PER_PGD
157 
158 #ifdef CONFIG_64BIT
159 #define MAX_ADDRBITS	(PGDIR_SHIFT + BITS_PER_PGD)
160 #define MAX_ADDRESS	(1UL << MAX_ADDRBITS)
161 #define SPACEID_SHIFT	(MAX_ADDRBITS - 32)
162 #else
163 #define MAX_ADDRBITS	(BITS_PER_LONG)
164 #define MAX_ADDRESS	(1UL << MAX_ADDRBITS)
165 #define SPACEID_SHIFT	0
166 #endif
167 
168 /* This calculates the number of initial pages we need for the initial
169  * page tables */
170 #if (KERNEL_INITIAL_ORDER) >= (PMD_SHIFT)
171 # define PT_INITIAL	(1 << (KERNEL_INITIAL_ORDER - PMD_SHIFT))
172 #else
173 # define PT_INITIAL	(1)  /* all initial PTEs fit into one page */
174 #endif
175 
176 /*
177  * pgd entries used up by user/kernel:
178  */
179 
180 #define FIRST_USER_ADDRESS	0UL
181 
182 /* NB: The tlb miss handlers make certain assumptions about the order */
183 /*     of the following bits, so be careful (One example, bits 25-31  */
184 /*     are moved together in one instruction).                        */
185 
186 #define _PAGE_READ_BIT     31   /* (0x001) read access allowed */
187 #define _PAGE_WRITE_BIT    30   /* (0x002) write access allowed */
188 #define _PAGE_EXEC_BIT     29   /* (0x004) execute access allowed */
189 #define _PAGE_GATEWAY_BIT  28   /* (0x008) privilege promotion allowed */
190 #define _PAGE_DMB_BIT      27   /* (0x010) Data Memory Break enable (B bit) */
191 #define _PAGE_DIRTY_BIT    26   /* (0x020) Page Dirty (D bit) */
192 #define _PAGE_REFTRAP_BIT  25   /* (0x040) Page Ref. Trap enable (T bit) */
193 #define _PAGE_NO_CACHE_BIT 24   /* (0x080) Uncached Page (U bit) */
194 #define _PAGE_ACCESSED_BIT 23   /* (0x100) Software: Page Accessed */
195 #define _PAGE_PRESENT_BIT  22   /* (0x200) Software: translation valid */
196 #define _PAGE_HPAGE_BIT    21   /* (0x400) Software: Huge Page */
197 #define _PAGE_USER_BIT     20   /* (0x800) Software: User accessible page */
198 
199 /* N.B. The bits are defined in terms of a 32 bit word above, so the */
200 /*      following macro is ok for both 32 and 64 bit.                */
201 
202 #define xlate_pabit(x) (31 - x)
203 
204 /* this defines the shift to the usable bits in the PTE it is set so
205  * that the valid bits _PAGE_PRESENT_BIT and _PAGE_USER_BIT are set
206  * to zero */
207 #define PTE_SHIFT	   	xlate_pabit(_PAGE_USER_BIT)
208 
209 /* PFN_PTE_SHIFT defines the shift of a PTE value to access the PFN field */
210 #define PFN_PTE_SHIFT		12
211 
212 #define _PAGE_READ     (1 << xlate_pabit(_PAGE_READ_BIT))
213 #define _PAGE_WRITE    (1 << xlate_pabit(_PAGE_WRITE_BIT))
214 #define _PAGE_RW       (_PAGE_READ | _PAGE_WRITE)
215 #define _PAGE_EXEC     (1 << xlate_pabit(_PAGE_EXEC_BIT))
216 #define _PAGE_GATEWAY  (1 << xlate_pabit(_PAGE_GATEWAY_BIT))
217 #define _PAGE_DMB      (1 << xlate_pabit(_PAGE_DMB_BIT))
218 #define _PAGE_DIRTY    (1 << xlate_pabit(_PAGE_DIRTY_BIT))
219 #define _PAGE_REFTRAP  (1 << xlate_pabit(_PAGE_REFTRAP_BIT))
220 #define _PAGE_NO_CACHE (1 << xlate_pabit(_PAGE_NO_CACHE_BIT))
221 #define _PAGE_ACCESSED (1 << xlate_pabit(_PAGE_ACCESSED_BIT))
222 #define _PAGE_PRESENT  (1 << xlate_pabit(_PAGE_PRESENT_BIT))
223 #define _PAGE_HUGE     (1 << xlate_pabit(_PAGE_HPAGE_BIT))
224 #define _PAGE_USER     (1 << xlate_pabit(_PAGE_USER_BIT))
225 
226 #define _PAGE_TABLE	(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)
227 #define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
228 #define _PAGE_KERNEL_RO	(_PAGE_PRESENT | _PAGE_READ | _PAGE_DIRTY | _PAGE_ACCESSED)
229 #define _PAGE_KERNEL_EXEC	(_PAGE_KERNEL_RO | _PAGE_EXEC)
230 #define _PAGE_KERNEL_RWX	(_PAGE_KERNEL_EXEC | _PAGE_WRITE)
231 #define _PAGE_KERNEL		(_PAGE_KERNEL_RO | _PAGE_WRITE)
232 
233 /* The pgd/pmd contains a ptr (in phys addr space); since all pgds/pmds
234  * are page-aligned, we don't care about the PAGE_OFFSET bits, except
235  * for a few meta-information bits, so we shift the address to be
236  * able to effectively address 40/42/44-bits of physical address space
237  * depending on 4k/16k/64k PAGE_SIZE */
238 #define _PxD_PRESENT_BIT   31
239 #define _PxD_ATTACHED_BIT  30
240 #define _PxD_VALID_BIT     29
241 
242 #define PxD_FLAG_PRESENT  (1 << xlate_pabit(_PxD_PRESENT_BIT))
243 #define PxD_FLAG_ATTACHED (1 << xlate_pabit(_PxD_ATTACHED_BIT))
244 #define PxD_FLAG_VALID    (1 << xlate_pabit(_PxD_VALID_BIT))
245 #define PxD_FLAG_MASK     (0xf)
246 #define PxD_FLAG_SHIFT    (4)
247 #define PxD_VALUE_SHIFT   (PFN_PTE_SHIFT-PxD_FLAG_SHIFT)
248 
249 #ifndef __ASSEMBLY__
250 
251 #define PAGE_NONE	__pgprot(_PAGE_PRESENT | _PAGE_USER)
252 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE)
253 /* Others seem to make this executable, I don't know if that's correct
254    or not.  The stack is mapped this way though so this is necessary
255    in the short term - dhd@linuxcare.com, 2000-08-08 */
256 #define PAGE_READONLY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ)
257 #define PAGE_WRITEONLY  __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_WRITE)
258 #define PAGE_EXECREAD   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_EXEC)
259 #define PAGE_COPY       PAGE_EXECREAD
260 #define PAGE_RWX        __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC)
261 #define PAGE_KERNEL	__pgprot(_PAGE_KERNEL)
262 #define PAGE_KERNEL_EXEC	__pgprot(_PAGE_KERNEL_EXEC)
263 #define PAGE_KERNEL_RWX	__pgprot(_PAGE_KERNEL_RWX)
264 #define PAGE_KERNEL_RO	__pgprot(_PAGE_KERNEL_RO)
265 #define PAGE_KERNEL_UNC	__pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
266 #define PAGE_GATEWAY    __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_GATEWAY| _PAGE_READ)
267 
268 
269 /*
270  * We could have an execute only page using "gateway - promote to priv
271  * level 3", but that is kind of silly. So, the way things are defined
272  * now, we must always have read permission for pages with execute
273  * permission. For the fun of it we'll go ahead and support write only
274  * pages.
275  */
276 
277 	 /*xwr*/
278 #define __P000  PAGE_NONE
279 #define __P001  PAGE_READONLY
280 #define __P010  __P000 /* copy on write */
281 #define __P011  __P001 /* copy on write */
282 #define __P100  PAGE_EXECREAD
283 #define __P101  PAGE_EXECREAD
284 #define __P110  __P100 /* copy on write */
285 #define __P111  __P101 /* copy on write */
286 
287 #define __S000  PAGE_NONE
288 #define __S001  PAGE_READONLY
289 #define __S010  PAGE_WRITEONLY
290 #define __S011  PAGE_SHARED
291 #define __S100  PAGE_EXECREAD
292 #define __S101  PAGE_EXECREAD
293 #define __S110  PAGE_RWX
294 #define __S111  PAGE_RWX
295 
296 
297 extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */
298 
299 /* initial page tables for 0-8MB for kernel */
300 
301 extern pte_t pg0[];
302 
303 /* zero page used for uninitialized stuff */
304 
305 extern unsigned long *empty_zero_page;
306 
307 /*
308  * ZERO_PAGE is a global shared page that is always zero: used
309  * for zero-mapped memory areas etc..
310  */
311 
312 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
313 
314 #define pte_none(x)     (pte_val(x) == 0)
315 #define pte_present(x)	(pte_val(x) & _PAGE_PRESENT)
316 #define pte_clear(mm, addr, xp)  set_pte_at(mm, addr, xp, __pte(0))
317 
318 #define pmd_flag(x)	(pmd_val(x) & PxD_FLAG_MASK)
319 #define pmd_address(x)	((unsigned long)(pmd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
320 #define pgd_flag(x)	(pgd_val(x) & PxD_FLAG_MASK)
321 #define pgd_address(x)	((unsigned long)(pgd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
322 
323 #if CONFIG_PGTABLE_LEVELS == 3
324 /* The first entry of the permanent pmd is not there if it contains
325  * the gateway marker */
326 #define pmd_none(x)	(!pmd_val(x) || pmd_flag(x) == PxD_FLAG_ATTACHED)
327 #else
328 #define pmd_none(x)	(!pmd_val(x))
329 #endif
330 #define pmd_bad(x)	(!(pmd_flag(x) & PxD_FLAG_VALID))
331 #define pmd_present(x)	(pmd_flag(x) & PxD_FLAG_PRESENT)
332 static inline void pmd_clear(pmd_t *pmd) {
333 #if CONFIG_PGTABLE_LEVELS == 3
334 	if (pmd_flag(*pmd) & PxD_FLAG_ATTACHED)
335 		/* This is the entry pointing to the permanent pmd
336 		 * attached to the pgd; cannot clear it */
337 		__pmd_val_set(*pmd, PxD_FLAG_ATTACHED);
338 	else
339 #endif
340 		__pmd_val_set(*pmd,  0);
341 }
342 
343 
344 
345 #if CONFIG_PGTABLE_LEVELS == 3
346 #define pgd_page_vaddr(pgd) ((unsigned long) __va(pgd_address(pgd)))
347 #define pgd_page(pgd)	virt_to_page((void *)pgd_page_vaddr(pgd))
348 
349 /* For 64 bit we have three level tables */
350 
351 #define pgd_none(x)     (!pgd_val(x))
352 #define pgd_bad(x)      (!(pgd_flag(x) & PxD_FLAG_VALID))
353 #define pgd_present(x)  (pgd_flag(x) & PxD_FLAG_PRESENT)
354 static inline void pgd_clear(pgd_t *pgd) {
355 #if CONFIG_PGTABLE_LEVELS == 3
356 	if(pgd_flag(*pgd) & PxD_FLAG_ATTACHED)
357 		/* This is the permanent pmd attached to the pgd; cannot
358 		 * free it */
359 		return;
360 #endif
361 	__pgd_val_set(*pgd, 0);
362 }
363 #else
364 /*
365  * The "pgd_xxx()" functions here are trivial for a folded two-level
366  * setup: the pgd is never bad, and a pmd always exists (as it's folded
367  * into the pgd entry)
368  */
369 static inline int pgd_none(pgd_t pgd)		{ return 0; }
370 static inline int pgd_bad(pgd_t pgd)		{ return 0; }
371 static inline int pgd_present(pgd_t pgd)	{ return 1; }
372 static inline void pgd_clear(pgd_t * pgdp)	{ }
373 #endif
374 
375 /*
376  * The following only work if pte_present() is true.
377  * Undefined behaviour if not..
378  */
379 static inline int pte_dirty(pte_t pte)		{ return pte_val(pte) & _PAGE_DIRTY; }
380 static inline int pte_young(pte_t pte)		{ return pte_val(pte) & _PAGE_ACCESSED; }
381 static inline int pte_write(pte_t pte)		{ return pte_val(pte) & _PAGE_WRITE; }
382 static inline int pte_special(pte_t pte)	{ return 0; }
383 
384 static inline pte_t pte_mkclean(pte_t pte)	{ pte_val(pte) &= ~_PAGE_DIRTY; return pte; }
385 static inline pte_t pte_mkold(pte_t pte)	{ pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
386 static inline pte_t pte_wrprotect(pte_t pte)	{ pte_val(pte) &= ~_PAGE_WRITE; return pte; }
387 static inline pte_t pte_mkdirty(pte_t pte)	{ pte_val(pte) |= _PAGE_DIRTY; return pte; }
388 static inline pte_t pte_mkyoung(pte_t pte)	{ pte_val(pte) |= _PAGE_ACCESSED; return pte; }
389 static inline pte_t pte_mkwrite(pte_t pte)	{ pte_val(pte) |= _PAGE_WRITE; return pte; }
390 static inline pte_t pte_mkspecial(pte_t pte)	{ return pte; }
391 
392 /*
393  * Huge pte definitions.
394  */
395 #ifdef CONFIG_HUGETLB_PAGE
396 #define pte_huge(pte)           (pte_val(pte) & _PAGE_HUGE)
397 #define pte_mkhuge(pte)         (__pte(pte_val(pte) | \
398 				 (parisc_requires_coherency() ? 0 : _PAGE_HUGE)))
399 #else
400 #define pte_huge(pte)           (0)
401 #define pte_mkhuge(pte)         (pte)
402 #endif
403 
404 
405 /*
406  * Conversion functions: convert a page and protection to a page entry,
407  * and a page entry and page directory to the page they refer to.
408  */
409 #define __mk_pte(addr,pgprot) \
410 ({									\
411 	pte_t __pte;							\
412 									\
413 	pte_val(__pte) = ((((addr)>>PAGE_SHIFT)<<PFN_PTE_SHIFT) + pgprot_val(pgprot));	\
414 									\
415 	__pte;								\
416 })
417 
418 #define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))
419 
420 static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
421 {
422 	pte_t pte;
423 	pte_val(pte) = (pfn << PFN_PTE_SHIFT) | pgprot_val(pgprot);
424 	return pte;
425 }
426 
427 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
428 { pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); return pte; }
429 
430 /* Permanent address of a page.  On parisc we don't have highmem. */
431 
432 #define pte_pfn(x)		(pte_val(x) >> PFN_PTE_SHIFT)
433 
434 #define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
435 
436 #define pmd_page_vaddr(pmd)	((unsigned long) __va(pmd_address(pmd)))
437 
438 #define __pmd_page(pmd) ((unsigned long) __va(pmd_address(pmd)))
439 #define pmd_page(pmd)	virt_to_page((void *)__pmd_page(pmd))
440 
441 #define pgd_index(address) ((address) >> PGDIR_SHIFT)
442 
443 /* to find an entry in a page-table-directory */
444 #define pgd_offset(mm, address) \
445 ((mm)->pgd + ((address) >> PGDIR_SHIFT))
446 
447 /* to find an entry in a kernel page-table-directory */
448 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
449 
450 /* Find an entry in the second-level page table.. */
451 
452 #if CONFIG_PGTABLE_LEVELS == 3
453 #define pmd_index(addr)         (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
454 #define pmd_offset(dir,address) \
455 ((pmd_t *) pgd_page_vaddr(*(dir)) + pmd_index(address))
456 #else
457 #define pmd_offset(dir,addr) ((pmd_t *) dir)
458 #endif
459 
460 /* Find an entry in the third-level page table.. */
461 #define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
462 #define pte_offset_kernel(pmd, address) \
463 	((pte_t *) pmd_page_vaddr(*(pmd)) + pte_index(address))
464 #define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address)
465 #define pte_unmap(pte) do { } while (0)
466 
467 #define pte_unmap(pte)			do { } while (0)
468 #define pte_unmap_nested(pte)		do { } while (0)
469 
470 extern void paging_init (void);
471 
472 /* Used for deferring calls to flush_dcache_page() */
473 
474 #define PG_dcache_dirty         PG_arch_1
475 
476 extern void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t *);
477 
478 /* Encode and de-code a swap entry */
479 
480 #define __swp_type(x)                     ((x).val & 0x1f)
481 #define __swp_offset(x)                   ( (((x).val >> 6) &  0x7) | \
482 					  (((x).val >> 8) & ~0x7) )
483 #define __swp_entry(type, offset)         ((swp_entry_t) { (type) | \
484 					    ((offset &  0x7) << 6) | \
485 					    ((offset & ~0x7) << 8) })
486 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
487 #define __swp_entry_to_pte(x)		((pte_t) { (x).val })
488 
489 
490 static inline spinlock_t *pgd_spinlock(pgd_t *pgd)
491 {
492 	if (unlikely(pgd == swapper_pg_dir))
493 		return &pa_swapper_pg_lock;
494 	return (spinlock_t *)((char *)pgd + (PAGE_SIZE << (PGD_ALLOC_ORDER - 1)));
495 }
496 
497 
498 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
499 {
500 	pte_t pte;
501 	unsigned long flags;
502 
503 	if (!pte_young(*ptep))
504 		return 0;
505 
506 	spin_lock_irqsave(pgd_spinlock(vma->vm_mm->pgd), flags);
507 	pte = *ptep;
508 	if (!pte_young(pte)) {
509 		spin_unlock_irqrestore(pgd_spinlock(vma->vm_mm->pgd), flags);
510 		return 0;
511 	}
512 	set_pte(ptep, pte_mkold(pte));
513 	purge_tlb_entries(vma->vm_mm, addr);
514 	spin_unlock_irqrestore(pgd_spinlock(vma->vm_mm->pgd), flags);
515 	return 1;
516 }
517 
518 struct mm_struct;
519 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
520 {
521 	pte_t old_pte;
522 	unsigned long flags;
523 
524 	spin_lock_irqsave(pgd_spinlock(mm->pgd), flags);
525 	old_pte = *ptep;
526 	set_pte(ptep, __pte(0));
527 	purge_tlb_entries(mm, addr);
528 	spin_unlock_irqrestore(pgd_spinlock(mm->pgd), flags);
529 
530 	return old_pte;
531 }
532 
533 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
534 {
535 	unsigned long flags;
536 	spin_lock_irqsave(pgd_spinlock(mm->pgd), flags);
537 	set_pte(ptep, pte_wrprotect(*ptep));
538 	purge_tlb_entries(mm, addr);
539 	spin_unlock_irqrestore(pgd_spinlock(mm->pgd), flags);
540 }
541 
542 #define pte_same(A,B)	(pte_val(A) == pte_val(B))
543 
544 struct seq_file;
545 extern void arch_report_meminfo(struct seq_file *m);
546 
547 #endif /* !__ASSEMBLY__ */
548 
549 
550 /* TLB page size encoding - see table 3-1 in parisc20.pdf */
551 #define _PAGE_SIZE_ENCODING_4K		0
552 #define _PAGE_SIZE_ENCODING_16K		1
553 #define _PAGE_SIZE_ENCODING_64K		2
554 #define _PAGE_SIZE_ENCODING_256K	3
555 #define _PAGE_SIZE_ENCODING_1M		4
556 #define _PAGE_SIZE_ENCODING_4M		5
557 #define _PAGE_SIZE_ENCODING_16M		6
558 #define _PAGE_SIZE_ENCODING_64M		7
559 
560 #if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
561 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_4K
562 #elif defined(CONFIG_PARISC_PAGE_SIZE_16KB)
563 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_16K
564 #elif defined(CONFIG_PARISC_PAGE_SIZE_64KB)
565 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_64K
566 #endif
567 
568 
569 #define pgprot_noncached(prot) __pgprot(pgprot_val(prot) | _PAGE_NO_CACHE)
570 
571 /* We provide our own get_unmapped_area to provide cache coherency */
572 
573 #define HAVE_ARCH_UNMAPPED_AREA
574 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
575 
576 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
577 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
578 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
579 #define __HAVE_ARCH_PTE_SAME
580 #include <asm-generic/pgtable.h>
581 
582 #endif /* _PARISC_PGTABLE_H */
583