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/*
* linux/include/asm-arm/pgtable.h
*
* Copyright (C) 2000-2001 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef _ASMARM_PGTABLE_H
#define _ASMARM_PGTABLE_H
#include <linux/config.h>
#include <asm/arch/memory.h>
#include <asm/proc-fns.h>
/*
* PMD_SHIFT determines the size of the area a second-level page table can map
* PGDIR_SHIFT determines what a third-level page table entry can map
*/
#define PMD_SHIFT 20
#define PGDIR_SHIFT 20
#define LIBRARY_TEXT_START 0x0c000000
#ifndef __ASSEMBLY__
extern void __pte_error(const char *file, int line, unsigned long val);
extern void __pmd_error(const char *file, int line, unsigned long val);
extern void __pgd_error(const char *file, int line, unsigned long val);
#define pte_ERROR(pte) __pte_error(__FILE__, __LINE__, pte_val(pte))
#define pmd_ERROR(pmd) __pmd_error(__FILE__, __LINE__, pmd_val(pmd))
#define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd_val(pgd))
#endif /* !__ASSEMBLY__ */
#define PMD_SIZE (1UL << PMD_SHIFT)
#define PMD_MASK (~(PMD_SIZE-1))
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
#define PGDIR_MASK (~(PGDIR_SIZE-1))
#define FIRST_USER_PGD_NR 1
#define USER_PTRS_PER_PGD ((TASK_SIZE/PGDIR_SIZE) - FIRST_USER_PGD_NR)
/*
* The table below defines the page protection levels that we insert into our
* Linux page table version. These get translated into the best that the
* architecture can perform. Note that on most ARM hardware:
* 1) We cannot do execute protection
* 2) If we could do execute protection, then read is implied
* 3) write implies read permissions
*/
#define __P000 PAGE_NONE
#define __P001 PAGE_READONLY
#define __P010 PAGE_COPY
#define __P011 PAGE_COPY
#define __P100 PAGE_READONLY
#define __P101 PAGE_READONLY
#define __P110 PAGE_COPY
#define __P111 PAGE_COPY
#define __S000 PAGE_NONE
#define __S001 PAGE_READONLY
#define __S010 PAGE_SHARED
#define __S011 PAGE_SHARED
#define __S100 PAGE_READONLY
#define __S101 PAGE_READONLY
#define __S110 PAGE_SHARED
#define __S111 PAGE_SHARED
#ifndef __ASSEMBLY__
/*
* ZERO_PAGE is a global shared page that is always zero: used
* for zero-mapped memory areas etc..
*/
extern struct page *empty_zero_page;
#define ZERO_PAGE(vaddr) (empty_zero_page)
#define pte_none(pte) (!pte_val(pte))
#define pte_clear(ptep) set_pte((ptep), __pte(0))
#ifndef CONFIG_DISCONTIGMEM
#define pte_page(x) (mem_map + (pte_val((x)) >> PAGE_SHIFT) - \
(PHYS_OFFSET >> PAGE_SHIFT))
#else
/*
* I'm not happy with this - we needlessly convert a physical address
* to a virtual one, and then immediately back to a physical address,
* which, if __va and __pa are expensive causes twice the expense for
* zero gain. --rmk
*/
#define pte_page(x) (virt_to_page(__va(pte_val((x)))))
#endif
#define pmd_none(pmd) (!pmd_val(pmd))
#define pmd_present(pmd) (pmd_val(pmd))
#define pmd_clear(pmdp) set_pmd(pmdp, __pmd(0))
/*
* Permanent address of a page. We never have highmem, so this is trivial.
*/
#define page_address(page) ((page)->virtual)
#define pages_to_mb(x) ((x) >> (20 - PAGE_SHIFT))
/*
* Conversion functions: convert a page and protection to a page entry,
* and a page entry and page directory to the page they refer to.
*/
static inline pte_t mk_pte_phys(unsigned long physpage, pgprot_t pgprot)
{
pte_t pte;
pte_val(pte) = physpage | pgprot_val(pgprot);
return pte;
}
#define mk_pte(page,pgprot) \
({ \
pte_t __pte; \
pte_val(__pte) = __pa(page_address(page)) + \
pgprot_val(pgprot); \
__pte; \
})
/*
* 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)
*/
#define pgd_none(pgd) (0)
#define pgd_bad(pgd) (0)
#define pgd_present(pgd) (1)
#define pgd_clear(pgdp)
#define page_pte_prot(page,prot) mk_pte(page, prot)
#define page_pte(page) mk_pte(page, __pgprot(0))
/* to find an entry in a page-table-directory */
#define pgd_index(addr) ((addr) >> PGDIR_SHIFT)
#define __pgd_offset(addr) pgd_index(addr)
#define pgd_offset(mm, addr) ((mm)->pgd+pgd_index(addr))
/* to find an entry in a kernel page-table-directory */
#define pgd_offset_k(addr) pgd_offset(&init_mm, addr)
/* Find an entry in the second-level page table.. */
#define pmd_offset(dir, addr) ((pmd_t *)(dir))
/* Find an entry in the third-level page table.. */
#define __pte_offset(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
#define pte_offset(dir, addr) ((pte_t *)pmd_page(*(dir)) + __pte_offset(addr))
#include <asm/proc/pgtable.h>
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;
}
extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
/* Encode and decode a swap entry.
*
* We support up to 32GB of swap on 4k machines
*/
#define SWP_TYPE(x) (((x).val >> 2) & 0x7f)
#define SWP_OFFSET(x) ((x).val >> 9)
#define SWP_ENTRY(type,offset) ((swp_entry_t) { ((type) << 2) | ((offset) << 9) })
#define pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
#define swp_entry_to_pte(swp) ((pte_t) { (swp).val })
/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
/* FIXME: this is not correct */
#define kern_addr_valid(addr) (1)
#include <asm-generic/pgtable.h>
extern void pgtable_cache_init(void);
#endif /* !__ASSEMBLY__ */
#endif /* _ASMARM_PGTABLE_H */
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