/* * linux/include/asm-arm/pgtable.h * * Copyright (C) 2000-2002 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 #include #include /* * 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_pfn(pte) (pte_val(pte) >> PAGE_SHIFT) #define pfn_pte(pfn,prot) (__pte(((pfn) << PAGE_SHIFT) | pgprot_val(prot))) #define pte_none(pte) (!pte_val(pte)) #define pte_clear(ptep) set_pte((ptep), __pte(0)) #define pte_page(pte) (pfn_to_page(pte_pfn(pte))) #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 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,prot) pfn_pte(page_to_pfn(page),prot) /* * 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) do { } while (0) #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 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 extern void pgtable_cache_init(void); /* * remap a physical address `phys' of size `size' with page protection `prot' * into virtual address `from' */ #define io_remap_page_range(from,phys,size,prot) \ remap_page_range(from,phys,size,prot) #endif /* !__ASSEMBLY__ */ #endif /* _ASMARM_PGTABLE_H */