[deliverable/linux.git] / include / asm-cris / pgtable.h

/*
 * CRIS pgtable.h - macros and functions to manipulate page tables.
 */

#ifndef _CRIS_PGTABLE_H
#define _CRIS_PGTABLE_H

#include <asm/page.h>
#include <asm-generic/pgtable-nopmd.h>

#ifndef __ASSEMBLY__
#include <linux/config.h>
#include <linux/sched.h>
#include <asm/mmu.h>
#endif
#include <asm/arch/pgtable.h>

/*
 * The Linux memory management assumes a three-level page table setup. On
 * CRIS, we use that, but "fold" the mid level into the top-level page
 * table. Since the MMU TLB is software loaded through an interrupt, it
 * supports any page table structure, so we could have used a three-level
 * setup, but for the amounts of memory we normally use, a two-level is
 * probably more efficient.
 *
 * This file contains the functions and defines necessary to modify and use
 * the CRIS page table tree.
 */
#ifndef __ASSEMBLY__
extern void paging_init(void);
#endif

/* Certain architectures need to do special things when pte's
 * within a page table are directly modified.  Thus, the following
 * hook is made available.
 */
#define set_pte(pteptr, pteval) ((*(pteptr)) = (pteval))
#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)

/*
 * (pmds are folded into pgds so this doesn't get actually called,
 * but the define is needed for a generic inline function.)
 */
#define set_pmd(pmdptr, pmdval) (*(pmdptr) = pmdval)
#define set_pgu(pudptr, pudval) (*(pudptr) = pudval)

/* PGDIR_SHIFT determines the size of the area a second-level page table can
 * map. It is equal to the page size times the number of PTE's that fit in
 * a PMD page. A PTE is 4-bytes in CRIS. Hence the following number.
 */

#define PGDIR_SHIFT	(PAGE_SHIFT + (PAGE_SHIFT-2))
#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
#define PGDIR_MASK	(~(PGDIR_SIZE-1))

/*
 * entries per page directory level: we use a two-level, so
 * we don't really have any PMD directory physically.
 * pointers are 4 bytes so we can use the page size and 
 * divide it by 4 (shift by 2).
 */
#define PTRS_PER_PTE	(1UL << (PAGE_SHIFT-2))
#define PTRS_PER_PGD	(1UL << (PAGE_SHIFT-2))

/* calculate how many PGD entries a user-level program can use
 * the first mappable virtual address is 0
 * (TASK_SIZE is the maximum virtual address space)
 */

#define USER_PTRS_PER_PGD       (TASK_SIZE/PGDIR_SIZE)
#define FIRST_USER_ADDRESS      0

/* zero page used for uninitialized stuff */
#ifndef __ASSEMBLY__
extern unsigned long empty_zero_page;
#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
#endif

/* number of bits that fit into a memory pointer */
#define BITS_PER_PTR			(8*sizeof(unsigned long))

/* to align the pointer to a pointer address */
#define PTR_MASK			(~(sizeof(void*)-1))

/* sizeof(void*)==1<<SIZEOF_PTR_LOG2 */
/* 64-bit machines, beware!  SRB. */
#define SIZEOF_PTR_LOG2			2

/* to find an entry in a page-table */
#define PAGE_PTR(address) \
((unsigned long)(address)>>(PAGE_SHIFT-SIZEOF_PTR_LOG2)&PTR_MASK&~PAGE_MASK)

/* to set the page-dir */
#define SET_PAGE_DIR(tsk,pgdir)

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

#define pmd_none(x)     (!pmd_val(x))
/* by removing the _PAGE_KERNEL bit from the comparision, the same pmd_bad
 * works for both _PAGE_TABLE and _KERNPG_TABLE pmd entries.
 */
#define	pmd_bad(x)	((pmd_val(x) & (~PAGE_MASK & ~_PAGE_KERNEL)) != _PAGE_TABLE)
#define pmd_present(x)	(pmd_val(x) & _PAGE_PRESENT)
#define pmd_clear(xp)	do { pmd_val(*(xp)) = 0; } while (0)

#ifndef __ASSEMBLY__

/*
 * The following only work if pte_present() is true.
 * Undefined behaviour if not..
 */

extern inline int pte_read(pte_t pte)           { return pte_val(pte) & _PAGE_READ; }
extern inline int pte_write(pte_t pte)          { return pte_val(pte) & _PAGE_WRITE; }
extern inline int pte_exec(pte_t pte)           { return pte_val(pte) & _PAGE_READ; }
extern inline int pte_dirty(pte_t pte)          { return pte_val(pte) & _PAGE_MODIFIED; }
extern inline int pte_young(pte_t pte)          { return pte_val(pte) & _PAGE_ACCESSED; }
extern inline int pte_file(pte_t pte)           { return pte_val(pte) & _PAGE_FILE; }

extern inline pte_t pte_wrprotect(pte_t pte)
{
        pte_val(pte) &= ~(_PAGE_WRITE | _PAGE_SILENT_WRITE);
        return pte;
}

extern inline pte_t pte_rdprotect(pte_t pte)
{
        pte_val(pte) &= ~(_PAGE_READ | _PAGE_SILENT_READ);
	return pte;
}

extern inline pte_t pte_exprotect(pte_t pte)
{
        pte_val(pte) &= ~(_PAGE_READ | _PAGE_SILENT_READ);
	return pte;
}

extern inline pte_t pte_mkclean(pte_t pte)
{
	pte_val(pte) &= ~(_PAGE_MODIFIED | _PAGE_SILENT_WRITE); 
	return pte; 
}

extern inline pte_t pte_mkold(pte_t pte)
{
	pte_val(pte) &= ~(_PAGE_ACCESSED | _PAGE_SILENT_READ);
	return pte;
}

extern inline pte_t pte_mkwrite(pte_t pte)
{
        pte_val(pte) |= _PAGE_WRITE;
        if (pte_val(pte) & _PAGE_MODIFIED)
                pte_val(pte) |= _PAGE_SILENT_WRITE;
        return pte;
}

extern inline pte_t pte_mkread(pte_t pte)
{
        pte_val(pte) |= _PAGE_READ;
        if (pte_val(pte) & _PAGE_ACCESSED)
                pte_val(pte) |= _PAGE_SILENT_READ;
        return pte;
}

extern inline pte_t pte_mkexec(pte_t pte)
{
        pte_val(pte) |= _PAGE_READ;
        if (pte_val(pte) & _PAGE_ACCESSED)
                pte_val(pte) |= _PAGE_SILENT_READ;
        return pte;
}

extern inline pte_t pte_mkdirty(pte_t pte)
{
        pte_val(pte) |= _PAGE_MODIFIED;
        if (pte_val(pte) & _PAGE_WRITE)
                pte_val(pte) |= _PAGE_SILENT_WRITE;
        return pte;
}

extern inline pte_t pte_mkyoung(pte_t pte)
{
        pte_val(pte) |= _PAGE_ACCESSED;
        if (pte_val(pte) & _PAGE_READ)
        {
                pte_val(pte) |= _PAGE_SILENT_READ;
                if ((pte_val(pte) & (_PAGE_WRITE | _PAGE_MODIFIED)) ==
		    (_PAGE_WRITE | _PAGE_MODIFIED))
                        pte_val(pte) |= _PAGE_SILENT_WRITE;
        }
        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.
 */

/* What actually goes as arguments to the various functions is less than
 * obvious, but a rule of thumb is that struct page's goes as struct page *,
 * really physical DRAM addresses are unsigned long's, and DRAM "virtual"
 * addresses (the 0xc0xxxxxx's) goes as void *'s.
 */

extern inline pte_t __mk_pte(void * page, pgprot_t pgprot)
{
	pte_t pte;
	/* the PTE needs a physical address */
	pte_val(pte) = __pa(page) | pgprot_val(pgprot);
	return pte;
}

#define mk_pte(page, pgprot) __mk_pte(page_address(page), (pgprot))

#define mk_pte_phys(physpage, pgprot) \
({                                                                      \
        pte_t __pte;                                                    \
                                                                        \
        pte_val(__pte) = (physpage) + pgprot_val(pgprot);               \
        __pte;                                                          \
})

extern 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; }


/* pte_val refers to a page in the 0x4xxxxxxx physical DRAM interval
 * __pte_page(pte_val) refers to the "virtual" DRAM interval
 * pte_pagenr refers to the page-number counted starting from the virtual DRAM start
 */

extern inline unsigned long __pte_page(pte_t pte)
{
	/* the PTE contains a physical address */
	return (unsigned long)__va(pte_val(pte) & PAGE_MASK);
}

#define pte_pagenr(pte)         ((__pte_page(pte) - PAGE_OFFSET) >> PAGE_SHIFT)

/* permanent address of a page */

#define __page_address(page)    (PAGE_OFFSET + (((page) - mem_map) << PAGE_SHIFT))
#define pte_page(pte)           (mem_map+pte_pagenr(pte))

/* only the pte's themselves need to point to physical DRAM (see above)
 * the pagetable links are purely handled within the kernel SW and thus
 * don't need the __pa and __va transformations.
 */

extern inline void pmd_set(pmd_t * pmdp, pte_t * ptep)
{ pmd_val(*pmdp) = _PAGE_TABLE | (unsigned long) ptep; }

#define pmd_page(pmd)		(pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT))
#define pmd_page_kernel(pmd)	((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))

/* to find an entry in a page-table-directory. */
#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))

/* to find an entry in a page-table-directory */
extern inline pgd_t * pgd_offset(struct mm_struct * mm, unsigned long address)
{
	return mm->pgd + pgd_index(address);
}

/* 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 third-level page table.. */
#define __pte_offset(address) \
	(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
#define pte_offset_kernel(dir, address) \
	((pte_t *) pmd_page_kernel(*(dir)) +  __pte_offset(address))
#define pte_offset_map(dir, address) \
	((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset(address))
#define pte_offset_map_nested(dir, address) pte_offset_map(dir, address)

#define pte_unmap(pte) do { } while (0)
#define pte_unmap_nested(pte) do { } while (0)
#define pte_pfn(x)		((unsigned long)(__va((x).pte)) >> PAGE_SHIFT)
#define pfn_pte(pfn, prot)	__pte((__pa((pfn) << PAGE_SHIFT)) | pgprot_val(prot))

#define pte_ERROR(e) \
        printk("%s:%d: bad pte %p(%08lx).\n", __FILE__, __LINE__, &(e), pte_val(e))
#define pgd_ERROR(e) \
        printk("%s:%d: bad pgd %p(%08lx).\n", __FILE__, __LINE__, &(e), pgd_val(e))


extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; /* defined in head.S */

/*
 * CRIS doesn't have any external MMU info: the kernel page
 * tables contain all the necessary information.
 * 
 * Actually I am not sure on what this could be used for.
 */
extern inline void update_mmu_cache(struct vm_area_struct * vma,
	unsigned long address, pte_t pte)
{
}

/* Encode and de-code a swap entry (must be !pte_none(e) && !pte_present(e)) */
/* Since the PAGE_PRESENT bit is bit 4, we can use the bits above */

#define __swp_type(x)			(((x).val >> 5) & 0x7f)
#define __swp_offset(x)			((x).val >> 12)
#define __swp_entry(type, offset)	((swp_entry_t) { ((type) << 5) | ((offset) << 12) })
#define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
#define __swp_entry_to_pte(x)		((pte_t) { (x).val })

#define kern_addr_valid(addr)   (1)

#include <asm-generic/pgtable.h>

/*
 * No page table caches to initialise
 */
#define pgtable_cache_init()   do { } while (0)

#define pte_to_pgoff(x)	(pte_val(x) >> 6)
#define pgoff_to_pte(x)	__pte(((x) << 6) | _PAGE_FILE)

typedef pte_t *pte_addr_t;

#endif /* __ASSEMBLY__ */
#endif /* _CRIS_PGTABLE_H */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* CRIS pgtable.h - macros and functions to manipulate page tables.
	3	*/
	4
	5	#ifndef _CRIS_PGTABLE_H
	6	#define _CRIS_PGTABLE_H
	7
5d01e6ce MS	8	#include <asm/page.h>
5d01e6ce MS	9	#include <asm-generic/pgtable-nopmd.h>
1da177e4 LT	10
	11	#ifndef __ASSEMBLY__
	12	#include <linux/config.h>
	13	#include <linux/sched.h>
	14	#include <asm/mmu.h>
	15	#endif
	16	#include <asm/arch/pgtable.h>
	17
	18	/*
	19	* The Linux memory management assumes a three-level page table setup. On
	20	* CRIS, we use that, but "fold" the mid level into the top-level page
	21	* table. Since the MMU TLB is software loaded through an interrupt, it
	22	* supports any page table structure, so we could have used a three-level
	23	* setup, but for the amounts of memory we normally use, a two-level is
	24	* probably more efficient.
	25	*
	26	* This file contains the functions and defines necessary to modify and use
	27	* the CRIS page table tree.
	28	*/
	29	#ifndef __ASSEMBLY__
	30	extern void paging_init(void);
	31	#endif
	32
	33	/* Certain architectures need to do special things when pte's
	34	* within a page table are directly modified. Thus, the following
	35	* hook is made available.
	36	*/
	37	#define set_pte(pteptr, pteval) ((*(pteptr)) = (pteval))
	38	#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
	39
	40	/*
	41	* (pmds are folded into pgds so this doesn't get actually called,
	42	* but the define is needed for a generic inline function.)
	43	*/
	44	#define set_pmd(pmdptr, pmdval) (*(pmdptr) = pmdval)
5d01e6ce	45	#define set_pgu(pudptr, pudval) (*(pudptr) = pudval)
1da177e4	46
5d01e6ce	47	/* PGDIR_SHIFT determines the size of the area a second-level page table can
1da177e4 LT	48	* map. It is equal to the page size times the number of PTE's that fit in
	49	* a PMD page. A PTE is 4-bytes in CRIS. Hence the following number.
	50	*/
	51
5d01e6ce	52	#define PGDIR_SHIFT (PAGE_SHIFT + (PAGE_SHIFT-2))
1da177e4 LT	53	#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
	54	#define PGDIR_MASK (~(PGDIR_SIZE-1))
	55
	56	/*
	57	* entries per page directory level: we use a two-level, so
	58	* we don't really have any PMD directory physically.
	59	* pointers are 4 bytes so we can use the page size and
	60	* divide it by 4 (shift by 2).
	61	*/
	62	#define PTRS_PER_PTE (1UL << (PAGE_SHIFT-2))
1da177e4 LT	63	#define PTRS_PER_PGD (1UL << (PAGE_SHIFT-2))
	64
	65	/* calculate how many PGD entries a user-level program can use
	66	* the first mappable virtual address is 0
	67	* (TASK_SIZE is the maximum virtual address space)
	68	*/
	69
	70	#define USER_PTRS_PER_PGD (TASK_SIZE/PGDIR_SIZE)
d455a369	71	#define FIRST_USER_ADDRESS 0
1da177e4 LT	72
	73	/* zero page used for uninitialized stuff */
	74	#ifndef __ASSEMBLY__
	75	extern unsigned long empty_zero_page;
	76	#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
	77	#endif
	78
	79	/* number of bits that fit into a memory pointer */
	80	#define BITS_PER_PTR (8*sizeof(unsigned long))
	81
	82	/* to align the pointer to a pointer address */
	83	#define PTR_MASK (~(sizeof(void*)-1))
	84
	85	/* sizeof(void)==1<<SIZEOF_PTR_LOG2 /
	86	/* 64-bit machines, beware! SRB. */
	87	#define SIZEOF_PTR_LOG2 2
	88
	89	/* to find an entry in a page-table */
	90	#define PAGE_PTR(address) \
	91	((unsigned long)(address)>>(PAGE_SHIFT-SIZEOF_PTR_LOG2)&PTR_MASK&~PAGE_MASK)
	92
	93	/* to set the page-dir */
	94	#define SET_PAGE_DIR(tsk,pgdir)
	95
	96	#define pte_none(x) (!pte_val(x))
	97	#define pte_present(x) (pte_val(x) & _PAGE_PRESENT)
	98	#define pte_clear(mm,addr,xp) do { pte_val(*(xp)) = 0; } while (0)
	99
5d01e6ce	100	#define pmd_none(x) (!pmd_val(x))
1da177e4 LT	101	/* by removing the _PAGE_KERNEL bit from the comparision, the same pmd_bad
	102	* works for both _PAGE_TABLE and _KERNPG_TABLE pmd entries.
	103	*/
	104	#define pmd_bad(x) ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_KERNEL)) != _PAGE_TABLE)
	105	#define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT)
	106	#define pmd_clear(xp) do { pmd_val(*(xp)) = 0; } while (0)
	107
	108	#ifndef __ASSEMBLY__
	109
1da177e4 LT	110	/*
	111	* The following only work if pte_present() is true.
	112	* Undefined behaviour if not..
	113	*/
	114
	115	extern inline int pte_read(pte_t pte) { return pte_val(pte) & _PAGE_READ; }
	116	extern inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_WRITE; }
	117	extern inline int pte_exec(pte_t pte) { return pte_val(pte) & _PAGE_READ; }
	118	extern inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_MODIFIED; }
	119	extern inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; }
	120	extern inline int pte_file(pte_t pte) { return pte_val(pte) & _PAGE_FILE; }
	121
	122	extern inline pte_t pte_wrprotect(pte_t pte)
	123	{
	124	pte_val(pte) &= ~(_PAGE_WRITE \| _PAGE_SILENT_WRITE);
	125	return pte;
	126	}
	127
	128	extern inline pte_t pte_rdprotect(pte_t pte)
	129	{
	130	pte_val(pte) &= ~(_PAGE_READ \| _PAGE_SILENT_READ);
	131	return pte;
	132	}
	133
	134	extern inline pte_t pte_exprotect(pte_t pte)
	135	{
	136	pte_val(pte) &= ~(_PAGE_READ \| _PAGE_SILENT_READ);
	137	return pte;
	138	}
	139
	140	extern inline pte_t pte_mkclean(pte_t pte)
	141	{
	142	pte_val(pte) &= ~(_PAGE_MODIFIED \| _PAGE_SILENT_WRITE);
	143	return pte;
	144	}
	145
	146	extern inline pte_t pte_mkold(pte_t pte)
	147	{
	148	pte_val(pte) &= ~(_PAGE_ACCESSED \| _PAGE_SILENT_READ);
	149	return pte;
	150	}
	151
	152	extern inline pte_t pte_mkwrite(pte_t pte)
	153	{
	154	pte_val(pte) \|= _PAGE_WRITE;
	155	if (pte_val(pte) & _PAGE_MODIFIED)
	156	pte_val(pte) \|= _PAGE_SILENT_WRITE;
	157	return pte;
	158	}
	159
	160	extern inline pte_t pte_mkread(pte_t pte)
	161	{
	162	pte_val(pte) \|= _PAGE_READ;
	163	if (pte_val(pte) & _PAGE_ACCESSED)
	164	pte_val(pte) \|= _PAGE_SILENT_READ;
	165	return pte;
	166	}
	167
	168	extern inline pte_t pte_mkexec(pte_t pte)
	169	{
	170	pte_val(pte) \|= _PAGE_READ;
	171	if (pte_val(pte) & _PAGE_ACCESSED)
	172	pte_val(pte) \|= _PAGE_SILENT_READ;
	173	return pte;
174	}
175
176	extern inline pte_t pte_mkdirty(pte_t pte)
177	{
178	pte_val(pte) \|= _PAGE_MODIFIED;
179	if (pte_val(pte) & _PAGE_WRITE)
180	pte_val(pte) \|= _PAGE_SILENT_WRITE;
181	return pte;
182	}
183
184	extern inline pte_t pte_mkyoung(pte_t pte)
185	{
186	pte_val(pte) \|= _PAGE_ACCESSED;
187	if (pte_val(pte) & _PAGE_READ)
188	{
189	pte_val(pte) \|= _PAGE_SILENT_READ;
190	if ((pte_val(pte) & (_PAGE_WRITE \| _PAGE_MODIFIED)) ==
191	(_PAGE_WRITE \| _PAGE_MODIFIED))
192	pte_val(pte) \|= _PAGE_SILENT_WRITE;
193	}
194	return pte;
195	}
196
197	/*
198	* Conversion functions: convert a page and protection to a page entry,
199	* and a page entry and page directory to the page they refer to.
200	*/
201
202	/* What actually goes as arguments to the various functions is less than
203	* obvious, but a rule of thumb is that struct page's goes as struct page *,
204	* really physical DRAM addresses are unsigned long's, and DRAM "virtual"
205	* addresses (the 0xc0xxxxxx's) goes as void *'s.
206	*/
207
208	extern inline pte_t __mk_pte(void * page, pgprot_t pgprot)
209	{
210	pte_t pte;
211	/* the PTE needs a physical address */
212	pte_val(pte) = __pa(page) \| pgprot_val(pgprot);
213	return pte;
214	}
215
216	#define mk_pte(page, pgprot) __mk_pte(page_address(page), (pgprot))
217
218	#define mk_pte_phys(physpage, pgprot) \
219	({ \
220	pte_t __pte; \
221	\
222	pte_val(__pte) = (physpage) + pgprot_val(pgprot); \
223	__pte; \
224	})
225
226	extern inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
227	{ pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) \| pgprot_val(newprot); return pte; }
228
229
230	/* pte_val refers to a page in the 0x4xxxxxxx physical DRAM interval
231	* __pte_page(pte_val) refers to the "virtual" DRAM interval
232	* pte_pagenr refers to the page-number counted starting from the virtual DRAM start
233	*/
234
235	extern inline unsigned long __pte_page(pte_t pte)
236	{
237	/* the PTE contains a physical address */
238	return (unsigned long)__va(pte_val(pte) & PAGE_MASK);
239	}
240
241	#define pte_pagenr(pte) ((__pte_page(pte) - PAGE_OFFSET) >> PAGE_SHIFT)
242
243	/* permanent address of a page */
244
245	#define __page_address(page) (PAGE_OFFSET + (((page) - mem_map) << PAGE_SHIFT))
246	#define pte_page(pte) (mem_map+pte_pagenr(pte))
247
248	/* only the pte's themselves need to point to physical DRAM (see above)
249	* the pagetable links are purely handled within the kernel SW and thus
250	* don't need the __pa and __va transformations.
251	*/
252
253	extern inline void pmd_set(pmd_t * pmdp, pte_t * ptep)
254	{ pmd_val(*pmdp) = _PAGE_TABLE \| (unsigned long) ptep; }
255
256	#define pmd_page(pmd) (pfn_to_page(pmd_val(pmd) >> PAGE_SHIFT))
257	#define pmd_page_kernel(pmd) ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK))
258
259	/* to find an entry in a page-table-directory. */
5d01e6ce	260	#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
1da177e4 LT	261
	262	/* to find an entry in a page-table-directory */
	263	extern inline pgd_t * pgd_offset(struct mm_struct * mm, unsigned long address)
	264	{
	265	return mm->pgd + pgd_index(address);
	266	}
	267
	268	/* to find an entry in a kernel page-table-directory */
	269	#define pgd_offset_k(address) pgd_offset(&init_mm, address)
	270
1da177e4 LT	271	/* Find an entry in the third-level page table.. */
	272	#define __pte_offset(address) \
	273	(((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
	274	#define pte_offset_kernel(dir, address) \
	275	((pte_t ) pmd_page_kernel((dir)) + __pte_offset(address))
	276	#define pte_offset_map(dir, address) \
	277	((pte_t )page_address(pmd_page((dir))) + __pte_offset(address))
	278	#define pte_offset_map_nested(dir, address) pte_offset_map(dir, address)
	279
	280	#define pte_unmap(pte) do { } while (0)
	281	#define pte_unmap_nested(pte) do { } while (0)
	282	#define pte_pfn(x) ((unsigned long)(__va((x).pte)) >> PAGE_SHIFT)
	283	#define pfn_pte(pfn, prot) __pte((__pa((pfn) << PAGE_SHIFT)) \| pgprot_val(prot))
	284
	285	#define pte_ERROR(e) \
	286	printk("%s:%d: bad pte %p(%08lx).\n", __FILE__, __LINE__, &(e), pte_val(e))
1da177e4 LT	287	#define pgd_ERROR(e) \
	288	printk("%s:%d: bad pgd %p(%08lx).\n", __FILE__, __LINE__, &(e), pgd_val(e))
	289
	290
	291	extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; /* defined in head.S */
	292
	293	/*
	294	* CRIS doesn't have any external MMU info: the kernel page
	295	* tables contain all the necessary information.
	296	*
	297	* Actually I am not sure on what this could be used for.
	298	*/
	299	extern inline void update_mmu_cache(struct vm_area_struct * vma,
	300	unsigned long address, pte_t pte)
	301	{
	302	}
	303
	304	/* Encode and de-code a swap entry (must be !pte_none(e) && !pte_present(e)) */
	305	/* Since the PAGE_PRESENT bit is bit 4, we can use the bits above */
	306
	307	#define __swp_type(x) (((x).val >> 5) & 0x7f)
	308	#define __swp_offset(x) ((x).val >> 12)
	309	#define __swp_entry(type, offset) ((swp_entry_t) { ((type) << 5) \| ((offset) << 12) })
	310	#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
	311	#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
	312
	313	#define kern_addr_valid(addr) (1)
	314
	315	#include <asm-generic/pgtable.h>
	316
	317	/*
	318	* No page table caches to initialise
	319	*/
	320	#define pgtable_cache_init() do { } while (0)
	321
	322	#define pte_to_pgoff(x) (pte_val(x) >> 6)
	323	#define pgoff_to_pte(x) __pte(((x) << 6) \| _PAGE_FILE)
	324
5d01e6ce MS	325	typedef pte_t *pte_addr_t;
5d01e6ce MS	326
1da177e4 LT	327	#endif /* __ASSEMBLY__ */
1da177e4 LT	328	#endif /* _CRIS_PGTABLE_H */