/* * arch/arm/include/asm/pgtable.h * * Copyright (C) 1995-2002 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 #ifndef CONFIG_MMU #include "pgtable-nommu.h" #else #include #include #include #include /* * Just any arbitrary offset to the start of the vmalloc VM area: the * current 8MB value just means that there will be a 8MB "hole" after the * physical memory until the kernel virtual memory starts. That means that * any out-of-bounds memory accesses will hopefully be caught. * The vmalloc() routines leaves a hole of 4kB between each vmalloced * area for the same reason. ;) * * Note that platforms may override VMALLOC_START, but they must provide * VMALLOC_END. VMALLOC_END defines the (exclusive) limit of this space, * which may not overlap IO space. */ #ifndef VMALLOC_START #define VMALLOC_OFFSET (8*1024*1024) #define VMALLOC_START (((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)) #endif #define LIBRARY_TEXT_START 0x0c000000 #ifndef __ASSEMBLY__ extern void __pte_error(const char *file, int line, pte_t); extern void __pmd_error(const char *file, int line, pmd_t); extern void __pgd_error(const char *file, int line, pgd_t); #define pte_ERROR(pte) __pte_error(__FILE__, __LINE__, pte) #define pmd_ERROR(pmd) __pmd_error(__FILE__, __LINE__, pmd) #define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd) /* * This is the lowest virtual address we can permit any user space * mapping to be mapped at. This is particularly important for * non-high vector CPUs. */ #define FIRST_USER_ADDRESS PAGE_SIZE /* * The pgprot_* and protection_map entries will be fixed up in runtime * to include the cachable and bufferable bits based on memory policy, * as well as any architecture dependent bits like global/ASID and SMP * shared mapping bits. */ #define _L_PTE_DEFAULT L_PTE_PRESENT | L_PTE_YOUNG extern pgprot_t pgprot_user; extern pgprot_t pgprot_kernel; #define _MOD_PROT(p, b) __pgprot(pgprot_val(p) | (b)) #define PAGE_NONE _MOD_PROT(pgprot_user, L_PTE_XN | L_PTE_RDONLY) #define PAGE_SHARED _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_XN) #define PAGE_SHARED_EXEC _MOD_PROT(pgprot_user, L_PTE_USER) #define PAGE_COPY _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN) #define PAGE_COPY_EXEC _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY) #define PAGE_READONLY _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN) #define PAGE_READONLY_EXEC _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY) #define PAGE_KERNEL _MOD_PROT(pgprot_kernel, L_PTE_XN) #define PAGE_KERNEL_EXEC pgprot_kernel #define __PAGE_NONE __pgprot(_L_PTE_DEFAULT | L_PTE_RDONLY | L_PTE_XN) #define __PAGE_SHARED __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_XN) #define __PAGE_SHARED_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER) #define __PAGE_COPY __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN) #define __PAGE_COPY_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY) #define __PAGE_READONLY __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN) #define __PAGE_READONLY_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY) #define __pgprot_modify(prot,mask,bits) \ __pgprot((pgprot_val(prot) & ~(mask)) | (bits)) #define pgprot_noncached(prot) \ __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED) #define pgprot_writecombine(prot) \ __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE) #define pgprot_stronglyordered(prot) \ __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED) #ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE #define pgprot_dmacoherent(prot) \ __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE | L_PTE_XN) #define __HAVE_PHYS_MEM_ACCESS_PROT struct file; extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, unsigned long size, pgprot_t vma_prot); #else #define pgprot_dmacoherent(prot) \ __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED | L_PTE_XN) #endif #endif /* __ASSEMBLY__ */ /* * 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_EXEC #define __P101 __PAGE_READONLY_EXEC #define __P110 __PAGE_COPY_EXEC #define __P111 __PAGE_COPY_EXEC #define __S000 __PAGE_NONE #define __S001 __PAGE_READONLY #define __S010 __PAGE_SHARED #define __S011 __PAGE_SHARED #define __S100 __PAGE_READONLY_EXEC #define __S101 __PAGE_READONLY_EXEC #define __S110 __PAGE_SHARED_EXEC #define __S111 __PAGE_SHARED_EXEC #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) extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; /* to find an entry in a page-table-directory */ #define pgd_index(addr) ((addr) >> PGDIR_SHIFT) #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) /* * 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 set_pgd(pgd,pgdp) do { } while (0) #define set_pud(pud,pudp) do { } while (0) /* Find an entry in the second-level page table.. */ #define pmd_offset(dir, addr) ((pmd_t *)(dir)) #define pmd_none(pmd) (!pmd_val(pmd)) #define pmd_present(pmd) (pmd_val(pmd)) #define pmd_bad(pmd) (pmd_val(pmd) & 2) #define copy_pmd(pmdpd,pmdps) \ do { \ pmdpd[0] = pmdps[0]; \ pmdpd[1] = pmdps[1]; \ flush_pmd_entry(pmdpd); \ } while (0) #define pmd_clear(pmdp) \ do { \ pmdp[0] = __pmd(0); \ pmdp[1] = __pmd(0); \ clean_pmd_entry(pmdp); \ } while (0) static inline pte_t *pmd_page_vaddr(pmd_t pmd) { return __va(pmd_val(pmd) & PHYS_MASK & (s32)PAGE_MASK); } #define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd) & PHYS_MASK)) /* we don't need complex calculations here as the pmd is folded into the pgd */ #define pmd_addr_end(addr,end) (end) #ifndef CONFIG_HIGHPTE #define __pte_map(pmd) pmd_page_vaddr(*(pmd)) #define __pte_unmap(pte) do { } while (0) #else #define __pte_map(pmd) (pte_t *)kmap_atomic(pmd_page(*(pmd))) #define __pte_unmap(pte) kunmap_atomic(pte) #endif #define pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) #define pte_offset_kernel(pmd,addr) (pmd_page_vaddr(*(pmd)) + pte_index(addr)) #define pte_offset_map(pmd,addr) (__pte_map(pmd) + pte_index(addr)) #define pte_unmap(pte) __pte_unmap(pte) #define pte_pfn(pte) ((pte_val(pte) & PHYS_MASK) >> PAGE_SHIFT) #define pfn_pte(pfn,prot) __pte(__pfn_to_phys(pfn) | pgprot_val(prot)) #define pte_page(pte) pfn_to_page(pte_pfn(pte)) #define mk_pte(page,prot) pfn_pte(page_to_pfn(page), prot) #define set_pte_ext(ptep,pte,ext) cpu_set_pte_ext(ptep,pte,ext) #define pte_clear(mm,addr,ptep) set_pte_ext(ptep, __pte(0), 0) #define pte_none(pte) (!pte_val(pte)) #define pte_present(pte) (pte_val(pte) & L_PTE_PRESENT) #define pte_write(pte) (!(pte_val(pte) & L_PTE_RDONLY)) #define pte_dirty(pte) (pte_val(pte) & L_PTE_DIRTY) #define pte_young(pte) (pte_val(pte) & L_PTE_YOUNG) #define pte_exec(pte) (!(pte_val(pte) & L_PTE_XN)) #define pte_special(pte) (0) #define pte_present_user(pte) \ ((pte_val(pte) & (L_PTE_PRESENT | L_PTE_USER)) == \ (L_PTE_PRESENT | L_PTE_USER)) #if __LINUX_ARM_ARCH__ < 6 static inline void __sync_icache_dcache(pte_t pteval) { } #else extern void __sync_icache_dcache(pte_t pteval); #endif static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, pte_t *ptep, pte_t pteval) { unsigned long ext = 0; if (addr < TASK_SIZE && pte_present_user(pteval)) { __sync_icache_dcache(pteval); ext |= PTE_EXT_NG; } set_pte_ext(ptep, pteval, ext); } #define PTE_BIT_FUNC(fn,op) \ static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; } PTE_BIT_FUNC(wrprotect, |= L_PTE_RDONLY); PTE_BIT_FUNC(mkwrite, &= ~L_PTE_RDONLY); PTE_BIT_FUNC(mkclean, &= ~L_PTE_DIRTY); PTE_BIT_FUNC(mkdirty, |= L_PTE_DIRTY); PTE_BIT_FUNC(mkold, &= ~L_PTE_YOUNG); PTE_BIT_FUNC(mkyoung, |= L_PTE_YOUNG); static inline pte_t pte_mkspecial(pte_t pte) { return pte; } static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) { const pteval_t mask = L_PTE_XN | L_PTE_RDONLY | L_PTE_USER; pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask); return pte; } /* * Encode and decode a swap entry. Swap entries are stored in the Linux * page tables as follows: * * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 * <--------------- offset ----------------------> < type -> 0 0 0 * * This gives us up to 31 swap files and 64GB per swap file. Note that * the offset field is always non-zero. */ #define __SWP_TYPE_SHIFT 3 #define __SWP_TYPE_BITS 5 #define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1) #define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT) #define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK) #define __swp_offset(x) ((x).val >> __SWP_OFFSET_SHIFT) #define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) }) #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) #define __swp_entry_to_pte(swp) ((pte_t) { (swp).val }) /* * It is an error for the kernel to have more swap files than we can * encode in the PTEs. This ensures that we know when MAX_SWAPFILES * is increased beyond what we presently support. */ #define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS) /* * Encode and decode a file entry. File entries are stored in the Linux * page tables as follows: * * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 * <----------------------- offset ------------------------> 1 0 0 */ #define pte_file(pte) (pte_val(pte) & L_PTE_FILE) #define pte_to_pgoff(x) (pte_val(x) >> 3) #define pgoff_to_pte(x) __pte(((x) << 3) | L_PTE_FILE) #define PTE_FILE_MAX_BITS 29 /* 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 /* * We provide our own arch_get_unmapped_area to cope with VIPT caches. */ #define HAVE_ARCH_UNMAPPED_AREA /* * remap a physical page `pfn' of size `size' with page protection `prot' * into virtual address `from' */ #define io_remap_pfn_range(vma,from,pfn,size,prot) \ remap_pfn_range(vma, from, pfn, size, prot) #define pgtable_cache_init() do { } while (0) void identity_mapping_add(pgd_t *, unsigned long, unsigned long); void identity_mapping_del(pgd_t *, unsigned long, unsigned long); #endif /* !__ASSEMBLY__ */ #endif /* CONFIG_MMU */ #endif /* _ASMARM_PGTABLE_H */