xref: /openbmc/linux/arch/parisc/include/asm/pgtable.h (revision da60fbe7)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _PARISC_PGTABLE_H
3 #define _PARISC_PGTABLE_H
4 
5 #include <asm/page.h>
6 
7 #if CONFIG_PGTABLE_LEVELS == 3
8 #include <asm-generic/pgtable-nopud.h>
9 #elif CONFIG_PGTABLE_LEVELS == 2
10 #include <asm-generic/pgtable-nopmd.h>
11 #endif
12 
13 #include <asm/fixmap.h>
14 
15 #ifndef __ASSEMBLY__
16 /*
17  * we simulate an x86-style page table for the linux mm code
18  */
19 
20 #include <linux/bitops.h>
21 #include <linux/spinlock.h>
22 #include <linux/mm_types.h>
23 #include <asm/processor.h>
24 #include <asm/cache.h>
25 
26 static inline spinlock_t *pgd_spinlock(pgd_t *);
27 
28 /*
29  * kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
30  * memory.  For the return value to be meaningful, ADDR must be >=
31  * PAGE_OFFSET.  This operation can be relatively expensive (e.g.,
32  * require a hash-, or multi-level tree-lookup or something of that
33  * sort) but it guarantees to return TRUE only if accessing the page
34  * at that address does not cause an error.  Note that there may be
35  * addresses for which kern_addr_valid() returns FALSE even though an
36  * access would not cause an error (e.g., this is typically true for
37  * memory mapped I/O regions.
38  *
39  * XXX Need to implement this for parisc.
40  */
41 #define kern_addr_valid(addr)	(1)
42 
43 /* This is for the serialization of PxTLB broadcasts. At least on the N class
44  * systems, only one PxTLB inter processor broadcast can be active at any one
45  * time on the Merced bus.
46 
47  * PTE updates are protected by locks in the PMD.
48  */
49 extern spinlock_t pa_tlb_flush_lock;
50 extern spinlock_t pa_swapper_pg_lock;
51 #if defined(CONFIG_64BIT) && defined(CONFIG_SMP)
52 extern int pa_serialize_tlb_flushes;
53 #else
54 #define pa_serialize_tlb_flushes        (0)
55 #endif
56 
57 #define purge_tlb_start(flags)  do { \
58 	if (pa_serialize_tlb_flushes)	\
59 		spin_lock_irqsave(&pa_tlb_flush_lock, flags); \
60 	else \
61 		local_irq_save(flags);	\
62 	} while (0)
63 #define purge_tlb_end(flags)	do { \
64 	if (pa_serialize_tlb_flushes)	\
65 		spin_unlock_irqrestore(&pa_tlb_flush_lock, flags); \
66 	else \
67 		local_irq_restore(flags); \
68 	} while (0)
69 
70 /* Purge data and instruction TLB entries. The TLB purge instructions
71  * are slow on SMP machines since the purge must be broadcast to all CPUs.
72  */
73 
74 static inline void purge_tlb_entries(struct mm_struct *mm, unsigned long addr)
75 {
76 	unsigned long flags;
77 
78 	purge_tlb_start(flags);
79 	mtsp(mm->context, 1);
80 	pdtlb(addr);
81 	pitlb(addr);
82 	purge_tlb_end(flags);
83 }
84 
85 /* Certain architectures need to do special things when PTEs
86  * within a page table are directly modified.  Thus, the following
87  * hook is made available.
88  */
89 #define set_pte(pteptr, pteval)                                 \
90         do{                                                     \
91                 *(pteptr) = (pteval);                           \
92         } while(0)
93 
94 #define set_pte_at(mm, addr, ptep, pteval)			\
95 	do {							\
96 		pte_t old_pte;					\
97 		unsigned long flags;				\
98 		spin_lock_irqsave(pgd_spinlock((mm)->pgd), flags);\
99 		old_pte = *ptep;				\
100 		set_pte(ptep, pteval);				\
101 		purge_tlb_entries(mm, addr);			\
102 		spin_unlock_irqrestore(pgd_spinlock((mm)->pgd), flags);\
103 	} while (0)
104 
105 #endif /* !__ASSEMBLY__ */
106 
107 #define pte_ERROR(e) \
108 	printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
109 #if CONFIG_PGTABLE_LEVELS == 3
110 #define pmd_ERROR(e) \
111 	printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, (unsigned long)pmd_val(e))
112 #endif
113 #define pgd_ERROR(e) \
114 	printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, (unsigned long)pgd_val(e))
115 
116 /* This is the size of the initially mapped kernel memory */
117 #if defined(CONFIG_64BIT)
118 #define KERNEL_INITIAL_ORDER	26	/* 1<<26 = 64MB */
119 #else
120 #define KERNEL_INITIAL_ORDER	25	/* 1<<25 = 32MB */
121 #endif
122 #define KERNEL_INITIAL_SIZE	(1 << KERNEL_INITIAL_ORDER)
123 
124 #if CONFIG_PGTABLE_LEVELS == 3
125 #define PGD_ORDER	1 /* Number of pages per pgd */
126 #define PMD_ORDER	1 /* Number of pages per pmd */
127 #define PGD_ALLOC_ORDER	(2 + 1) /* first pgd contains pmd */
128 #else
129 #define PGD_ORDER	1 /* Number of pages per pgd */
130 #define PGD_ALLOC_ORDER	(PGD_ORDER + 1)
131 #endif
132 
133 /* Definitions for 3rd level (we use PLD here for Page Lower directory
134  * because PTE_SHIFT is used lower down to mean shift that has to be
135  * done to get usable bits out of the PTE) */
136 #define PLD_SHIFT	PAGE_SHIFT
137 #define PLD_SIZE	PAGE_SIZE
138 #define BITS_PER_PTE	(PAGE_SHIFT - BITS_PER_PTE_ENTRY)
139 #define PTRS_PER_PTE    (1UL << BITS_PER_PTE)
140 
141 /* Definitions for 2nd level */
142 #if CONFIG_PGTABLE_LEVELS == 3
143 #define PMD_SHIFT       (PLD_SHIFT + BITS_PER_PTE)
144 #define PMD_SIZE	(1UL << PMD_SHIFT)
145 #define PMD_MASK	(~(PMD_SIZE-1))
146 #define BITS_PER_PMD	(PAGE_SHIFT + PMD_ORDER - BITS_PER_PMD_ENTRY)
147 #define PTRS_PER_PMD    (1UL << BITS_PER_PMD)
148 #else
149 #define BITS_PER_PMD	0
150 #endif
151 
152 /* Definitions for 1st level */
153 #define PGDIR_SHIFT	(PLD_SHIFT + BITS_PER_PTE + BITS_PER_PMD)
154 #if (PGDIR_SHIFT + PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY) > BITS_PER_LONG
155 #define BITS_PER_PGD	(BITS_PER_LONG - PGDIR_SHIFT)
156 #else
157 #define BITS_PER_PGD	(PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY)
158 #endif
159 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
160 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
161 #define PTRS_PER_PGD    (1UL << BITS_PER_PGD)
162 #define USER_PTRS_PER_PGD       PTRS_PER_PGD
163 
164 #ifdef CONFIG_64BIT
165 #define MAX_ADDRBITS	(PGDIR_SHIFT + BITS_PER_PGD)
166 #define MAX_ADDRESS	(1UL << MAX_ADDRBITS)
167 #define SPACEID_SHIFT	(MAX_ADDRBITS - 32)
168 #else
169 #define MAX_ADDRBITS	(BITS_PER_LONG)
170 #define MAX_ADDRESS	(1UL << MAX_ADDRBITS)
171 #define SPACEID_SHIFT	0
172 #endif
173 
174 /* This calculates the number of initial pages we need for the initial
175  * page tables */
176 #if (KERNEL_INITIAL_ORDER) >= (PMD_SHIFT)
177 # define PT_INITIAL	(1 << (KERNEL_INITIAL_ORDER - PMD_SHIFT))
178 #else
179 # define PT_INITIAL	(1)  /* all initial PTEs fit into one page */
180 #endif
181 
182 /*
183  * pgd entries used up by user/kernel:
184  */
185 
186 #define FIRST_USER_ADDRESS	0UL
187 
188 /* NB: The tlb miss handlers make certain assumptions about the order */
189 /*     of the following bits, so be careful (One example, bits 25-31  */
190 /*     are moved together in one instruction).                        */
191 
192 #define _PAGE_READ_BIT     31   /* (0x001) read access allowed */
193 #define _PAGE_WRITE_BIT    30   /* (0x002) write access allowed */
194 #define _PAGE_EXEC_BIT     29   /* (0x004) execute access allowed */
195 #define _PAGE_GATEWAY_BIT  28   /* (0x008) privilege promotion allowed */
196 #define _PAGE_DMB_BIT      27   /* (0x010) Data Memory Break enable (B bit) */
197 #define _PAGE_DIRTY_BIT    26   /* (0x020) Page Dirty (D bit) */
198 #define _PAGE_REFTRAP_BIT  25   /* (0x040) Page Ref. Trap enable (T bit) */
199 #define _PAGE_NO_CACHE_BIT 24   /* (0x080) Uncached Page (U bit) */
200 #define _PAGE_ACCESSED_BIT 23   /* (0x100) Software: Page Accessed */
201 #define _PAGE_PRESENT_BIT  22   /* (0x200) Software: translation valid */
202 #define _PAGE_HPAGE_BIT    21   /* (0x400) Software: Huge Page */
203 #define _PAGE_USER_BIT     20   /* (0x800) Software: User accessible page */
204 
205 /* N.B. The bits are defined in terms of a 32 bit word above, so the */
206 /*      following macro is ok for both 32 and 64 bit.                */
207 
208 #define xlate_pabit(x) (31 - x)
209 
210 /* this defines the shift to the usable bits in the PTE it is set so
211  * that the valid bits _PAGE_PRESENT_BIT and _PAGE_USER_BIT are set
212  * to zero */
213 #define PTE_SHIFT	   	xlate_pabit(_PAGE_USER_BIT)
214 
215 /* PFN_PTE_SHIFT defines the shift of a PTE value to access the PFN field */
216 #define PFN_PTE_SHIFT		12
217 
218 #define _PAGE_READ     (1 << xlate_pabit(_PAGE_READ_BIT))
219 #define _PAGE_WRITE    (1 << xlate_pabit(_PAGE_WRITE_BIT))
220 #define _PAGE_RW       (_PAGE_READ | _PAGE_WRITE)
221 #define _PAGE_EXEC     (1 << xlate_pabit(_PAGE_EXEC_BIT))
222 #define _PAGE_GATEWAY  (1 << xlate_pabit(_PAGE_GATEWAY_BIT))
223 #define _PAGE_DMB      (1 << xlate_pabit(_PAGE_DMB_BIT))
224 #define _PAGE_DIRTY    (1 << xlate_pabit(_PAGE_DIRTY_BIT))
225 #define _PAGE_REFTRAP  (1 << xlate_pabit(_PAGE_REFTRAP_BIT))
226 #define _PAGE_NO_CACHE (1 << xlate_pabit(_PAGE_NO_CACHE_BIT))
227 #define _PAGE_ACCESSED (1 << xlate_pabit(_PAGE_ACCESSED_BIT))
228 #define _PAGE_PRESENT  (1 << xlate_pabit(_PAGE_PRESENT_BIT))
229 #define _PAGE_HUGE     (1 << xlate_pabit(_PAGE_HPAGE_BIT))
230 #define _PAGE_USER     (1 << xlate_pabit(_PAGE_USER_BIT))
231 
232 #define _PAGE_TABLE	(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)
233 #define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
234 #define _PAGE_KERNEL_RO	(_PAGE_PRESENT | _PAGE_READ | _PAGE_DIRTY | _PAGE_ACCESSED)
235 #define _PAGE_KERNEL_EXEC	(_PAGE_KERNEL_RO | _PAGE_EXEC)
236 #define _PAGE_KERNEL_RWX	(_PAGE_KERNEL_EXEC | _PAGE_WRITE)
237 #define _PAGE_KERNEL		(_PAGE_KERNEL_RO | _PAGE_WRITE)
238 
239 /* The pgd/pmd contains a ptr (in phys addr space); since all pgds/pmds
240  * are page-aligned, we don't care about the PAGE_OFFSET bits, except
241  * for a few meta-information bits, so we shift the address to be
242  * able to effectively address 40/42/44-bits of physical address space
243  * depending on 4k/16k/64k PAGE_SIZE */
244 #define _PxD_PRESENT_BIT   31
245 #define _PxD_ATTACHED_BIT  30
246 #define _PxD_VALID_BIT     29
247 
248 #define PxD_FLAG_PRESENT  (1 << xlate_pabit(_PxD_PRESENT_BIT))
249 #define PxD_FLAG_ATTACHED (1 << xlate_pabit(_PxD_ATTACHED_BIT))
250 #define PxD_FLAG_VALID    (1 << xlate_pabit(_PxD_VALID_BIT))
251 #define PxD_FLAG_MASK     (0xf)
252 #define PxD_FLAG_SHIFT    (4)
253 #define PxD_VALUE_SHIFT   (PFN_PTE_SHIFT-PxD_FLAG_SHIFT)
254 
255 #ifndef __ASSEMBLY__
256 
257 #define PAGE_NONE	__pgprot(_PAGE_PRESENT | _PAGE_USER)
258 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE)
259 /* Others seem to make this executable, I don't know if that's correct
260    or not.  The stack is mapped this way though so this is necessary
261    in the short term - dhd@linuxcare.com, 2000-08-08 */
262 #define PAGE_READONLY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ)
263 #define PAGE_WRITEONLY  __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_WRITE)
264 #define PAGE_EXECREAD   __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_EXEC)
265 #define PAGE_COPY       PAGE_EXECREAD
266 #define PAGE_RWX        __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC)
267 #define PAGE_KERNEL	__pgprot(_PAGE_KERNEL)
268 #define PAGE_KERNEL_EXEC	__pgprot(_PAGE_KERNEL_EXEC)
269 #define PAGE_KERNEL_RWX	__pgprot(_PAGE_KERNEL_RWX)
270 #define PAGE_KERNEL_RO	__pgprot(_PAGE_KERNEL_RO)
271 #define PAGE_KERNEL_UNC	__pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
272 #define PAGE_GATEWAY    __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_GATEWAY| _PAGE_READ)
273 
274 
275 /*
276  * We could have an execute only page using "gateway - promote to priv
277  * level 3", but that is kind of silly. So, the way things are defined
278  * now, we must always have read permission for pages with execute
279  * permission. For the fun of it we'll go ahead and support write only
280  * pages.
281  */
282 
283 	 /*xwr*/
284 #define __P000  PAGE_NONE
285 #define __P001  PAGE_READONLY
286 #define __P010  __P000 /* copy on write */
287 #define __P011  __P001 /* copy on write */
288 #define __P100  PAGE_EXECREAD
289 #define __P101  PAGE_EXECREAD
290 #define __P110  __P100 /* copy on write */
291 #define __P111  __P101 /* copy on write */
292 
293 #define __S000  PAGE_NONE
294 #define __S001  PAGE_READONLY
295 #define __S010  PAGE_WRITEONLY
296 #define __S011  PAGE_SHARED
297 #define __S100  PAGE_EXECREAD
298 #define __S101  PAGE_EXECREAD
299 #define __S110  PAGE_RWX
300 #define __S111  PAGE_RWX
301 
302 
303 extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */
304 
305 /* initial page tables for 0-8MB for kernel */
306 
307 extern pte_t pg0[];
308 
309 /* zero page used for uninitialized stuff */
310 
311 extern unsigned long *empty_zero_page;
312 
313 /*
314  * ZERO_PAGE is a global shared page that is always zero: used
315  * for zero-mapped memory areas etc..
316  */
317 
318 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
319 
320 #define pte_none(x)     (pte_val(x) == 0)
321 #define pte_present(x)	(pte_val(x) & _PAGE_PRESENT)
322 #define pte_clear(mm, addr, xp)  set_pte_at(mm, addr, xp, __pte(0))
323 
324 #define pmd_flag(x)	(pmd_val(x) & PxD_FLAG_MASK)
325 #define pmd_address(x)	((unsigned long)(pmd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
326 #define pud_flag(x)	(pud_val(x) & PxD_FLAG_MASK)
327 #define pud_address(x)	((unsigned long)(pud_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
328 #define pgd_flag(x)	(pgd_val(x) & PxD_FLAG_MASK)
329 #define pgd_address(x)	((unsigned long)(pgd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
330 
331 #if CONFIG_PGTABLE_LEVELS == 3
332 /* The first entry of the permanent pmd is not there if it contains
333  * the gateway marker */
334 #define pmd_none(x)	(!pmd_val(x) || pmd_flag(x) == PxD_FLAG_ATTACHED)
335 #else
336 #define pmd_none(x)	(!pmd_val(x))
337 #endif
338 #define pmd_bad(x)	(!(pmd_flag(x) & PxD_FLAG_VALID))
339 #define pmd_present(x)	(pmd_flag(x) & PxD_FLAG_PRESENT)
340 static inline void pmd_clear(pmd_t *pmd) {
341 #if CONFIG_PGTABLE_LEVELS == 3
342 	if (pmd_flag(*pmd) & PxD_FLAG_ATTACHED)
343 		/* This is the entry pointing to the permanent pmd
344 		 * attached to the pgd; cannot clear it */
345 		set_pmd(pmd, __pmd(PxD_FLAG_ATTACHED));
346 	else
347 #endif
348 		set_pmd(pmd,  __pmd(0));
349 }
350 
351 
352 
353 #if CONFIG_PGTABLE_LEVELS == 3
354 #define pud_page_vaddr(pud) ((unsigned long) __va(pud_address(pud)))
355 #define pud_page(pud)	virt_to_page((void *)pud_page_vaddr(pud))
356 
357 /* For 64 bit we have three level tables */
358 
359 #define pud_none(x)     (!pud_val(x))
360 #define pud_bad(x)      (!(pud_flag(x) & PxD_FLAG_VALID))
361 #define pud_present(x)  (pud_flag(x) & PxD_FLAG_PRESENT)
362 static inline void pud_clear(pud_t *pud) {
363 #if CONFIG_PGTABLE_LEVELS == 3
364 	if(pud_flag(*pud) & PxD_FLAG_ATTACHED)
365 		/* This is the permanent pmd attached to the pud; cannot
366 		 * free it */
367 		return;
368 #endif
369 	set_pud(pud, __pud(0));
370 }
371 #endif
372 
373 /*
374  * The following only work if pte_present() is true.
375  * Undefined behaviour if not..
376  */
377 static inline int pte_dirty(pte_t pte)		{ return pte_val(pte) & _PAGE_DIRTY; }
378 static inline int pte_young(pte_t pte)		{ return pte_val(pte) & _PAGE_ACCESSED; }
379 static inline int pte_write(pte_t pte)		{ return pte_val(pte) & _PAGE_WRITE; }
380 static inline int pte_special(pte_t pte)	{ return 0; }
381 
382 static inline pte_t pte_mkclean(pte_t pte)	{ pte_val(pte) &= ~_PAGE_DIRTY; return pte; }
383 static inline pte_t pte_mkold(pte_t pte)	{ pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
384 static inline pte_t pte_wrprotect(pte_t pte)	{ pte_val(pte) &= ~_PAGE_WRITE; return pte; }
385 static inline pte_t pte_mkdirty(pte_t pte)	{ pte_val(pte) |= _PAGE_DIRTY; return pte; }
386 static inline pte_t pte_mkyoung(pte_t pte)	{ pte_val(pte) |= _PAGE_ACCESSED; return pte; }
387 static inline pte_t pte_mkwrite(pte_t pte)	{ pte_val(pte) |= _PAGE_WRITE; return pte; }
388 static inline pte_t pte_mkspecial(pte_t pte)	{ return pte; }
389 
390 /*
391  * Huge pte definitions.
392  */
393 #ifdef CONFIG_HUGETLB_PAGE
394 #define pte_huge(pte)           (pte_val(pte) & _PAGE_HUGE)
395 #define pte_mkhuge(pte)         (__pte(pte_val(pte) | \
396 				 (parisc_requires_coherency() ? 0 : _PAGE_HUGE)))
397 #else
398 #define pte_huge(pte)           (0)
399 #define pte_mkhuge(pte)         (pte)
400 #endif
401 
402 
403 /*
404  * Conversion functions: convert a page and protection to a page entry,
405  * and a page entry and page directory to the page they refer to.
406  */
407 #define __mk_pte(addr,pgprot) \
408 ({									\
409 	pte_t __pte;							\
410 									\
411 	pte_val(__pte) = ((((addr)>>PAGE_SHIFT)<<PFN_PTE_SHIFT) + pgprot_val(pgprot));	\
412 									\
413 	__pte;								\
414 })
415 
416 #define mk_pte(page, pgprot)	pfn_pte(page_to_pfn(page), (pgprot))
417 
418 static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
419 {
420 	pte_t pte;
421 	pte_val(pte) = (pfn << PFN_PTE_SHIFT) | pgprot_val(pgprot);
422 	return pte;
423 }
424 
425 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
426 { pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); return pte; }
427 
428 /* Permanent address of a page.  On parisc we don't have highmem. */
429 
430 #define pte_pfn(x)		(pte_val(x) >> PFN_PTE_SHIFT)
431 
432 #define pte_page(pte)		(pfn_to_page(pte_pfn(pte)))
433 
434 #define pmd_page_vaddr(pmd)	((unsigned long) __va(pmd_address(pmd)))
435 
436 #define __pmd_page(pmd) ((unsigned long) __va(pmd_address(pmd)))
437 #define pmd_page(pmd)	virt_to_page((void *)__pmd_page(pmd))
438 
439 #define pgd_index(address) ((address) >> PGDIR_SHIFT)
440 
441 /* to find an entry in a page-table-directory */
442 #define pgd_offset(mm, address) \
443 ((mm)->pgd + ((address) >> PGDIR_SHIFT))
444 
445 /* to find an entry in a kernel page-table-directory */
446 #define pgd_offset_k(address) pgd_offset(&init_mm, address)
447 
448 /* Find an entry in the second-level page table.. */
449 
450 #if CONFIG_PGTABLE_LEVELS == 3
451 #define pmd_index(addr)         (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1))
452 #define pmd_offset(dir,address) \
453 ((pmd_t *) pud_page_vaddr(*(dir)) + pmd_index(address))
454 #else
455 #define pmd_offset(dir,addr) ((pmd_t *) dir)
456 #endif
457 
458 /* Find an entry in the third-level page table.. */
459 #define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
460 #define pte_offset_kernel(pmd, address) \
461 	((pte_t *) pmd_page_vaddr(*(pmd)) + pte_index(address))
462 #define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address)
463 #define pte_unmap(pte) do { } while (0)
464 
465 #define pte_unmap(pte)			do { } while (0)
466 #define pte_unmap_nested(pte)		do { } while (0)
467 
468 extern void paging_init (void);
469 
470 /* Used for deferring calls to flush_dcache_page() */
471 
472 #define PG_dcache_dirty         PG_arch_1
473 
474 extern void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t *);
475 
476 /* Encode and de-code a swap entry */
477 
478 #define __swp_type(x)                     ((x).val & 0x1f)
479 #define __swp_offset(x)                   ( (((x).val >> 6) &  0x7) | \
480 					  (((x).val >> 8) & ~0x7) )
481 #define __swp_entry(type, offset)         ((swp_entry_t) { (type) | \
482 					    ((offset &  0x7) << 6) | \
483 					    ((offset & ~0x7) << 8) })
484 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
485 #define __swp_entry_to_pte(x)		((pte_t) { (x).val })
486 
487 
488 static inline spinlock_t *pgd_spinlock(pgd_t *pgd)
489 {
490 	if (unlikely(pgd == swapper_pg_dir))
491 		return &pa_swapper_pg_lock;
492 	return (spinlock_t *)((char *)pgd + (PAGE_SIZE << (PGD_ALLOC_ORDER - 1)));
493 }
494 
495 
496 static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
497 {
498 	pte_t pte;
499 	unsigned long flags;
500 
501 	if (!pte_young(*ptep))
502 		return 0;
503 
504 	spin_lock_irqsave(pgd_spinlock(vma->vm_mm->pgd), flags);
505 	pte = *ptep;
506 	if (!pte_young(pte)) {
507 		spin_unlock_irqrestore(pgd_spinlock(vma->vm_mm->pgd), flags);
508 		return 0;
509 	}
510 	set_pte(ptep, pte_mkold(pte));
511 	purge_tlb_entries(vma->vm_mm, addr);
512 	spin_unlock_irqrestore(pgd_spinlock(vma->vm_mm->pgd), flags);
513 	return 1;
514 }
515 
516 struct mm_struct;
517 static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
518 {
519 	pte_t old_pte;
520 	unsigned long flags;
521 
522 	spin_lock_irqsave(pgd_spinlock(mm->pgd), flags);
523 	old_pte = *ptep;
524 	set_pte(ptep, __pte(0));
525 	purge_tlb_entries(mm, addr);
526 	spin_unlock_irqrestore(pgd_spinlock(mm->pgd), flags);
527 
528 	return old_pte;
529 }
530 
531 static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
532 {
533 	unsigned long flags;
534 	spin_lock_irqsave(pgd_spinlock(mm->pgd), flags);
535 	set_pte(ptep, pte_wrprotect(*ptep));
536 	purge_tlb_entries(mm, addr);
537 	spin_unlock_irqrestore(pgd_spinlock(mm->pgd), flags);
538 }
539 
540 #define pte_same(A,B)	(pte_val(A) == pte_val(B))
541 
542 struct seq_file;
543 extern void arch_report_meminfo(struct seq_file *m);
544 
545 #endif /* !__ASSEMBLY__ */
546 
547 
548 /* TLB page size encoding - see table 3-1 in parisc20.pdf */
549 #define _PAGE_SIZE_ENCODING_4K		0
550 #define _PAGE_SIZE_ENCODING_16K		1
551 #define _PAGE_SIZE_ENCODING_64K		2
552 #define _PAGE_SIZE_ENCODING_256K	3
553 #define _PAGE_SIZE_ENCODING_1M		4
554 #define _PAGE_SIZE_ENCODING_4M		5
555 #define _PAGE_SIZE_ENCODING_16M		6
556 #define _PAGE_SIZE_ENCODING_64M		7
557 
558 #if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
559 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_4K
560 #elif defined(CONFIG_PARISC_PAGE_SIZE_16KB)
561 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_16K
562 #elif defined(CONFIG_PARISC_PAGE_SIZE_64KB)
563 # define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_64K
564 #endif
565 
566 
567 #define pgprot_noncached(prot) __pgprot(pgprot_val(prot) | _PAGE_NO_CACHE)
568 
569 /* We provide our own get_unmapped_area to provide cache coherency */
570 
571 #define HAVE_ARCH_UNMAPPED_AREA
572 #define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
573 
574 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
575 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
576 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
577 #define __HAVE_ARCH_PTE_SAME
578 #include <asm-generic/pgtable.h>
579 
580 #endif /* _PARISC_PGTABLE_H */
581