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Diffstat (limited to 'arch/arm/include/asm/pgtable.h')
| -rw-r--r-- | arch/arm/include/asm/pgtable.h | 331 |
1 files changed, 331 insertions, 0 deletions
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h new file mode 100644 index 000000000..d38d50349 --- /dev/null +++ b/arch/arm/include/asm/pgtable.h @@ -0,0 +1,331 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * arch/arm/include/asm/pgtable.h + * + * Copyright (C) 1995-2002 Russell King + */ +#ifndef _ASMARM_PGTABLE_H +#define _ASMARM_PGTABLE_H + +#include <linux/const.h> +#include <asm/proc-fns.h> + +#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) +#endif + +#ifndef CONFIG_MMU + +#include <asm-generic/pgtable-nopud.h> +#include <asm/pgtable-nommu.h> + +#else + +#include <asm-generic/pgtable-nopud.h> +#include <asm/memory.h> +#include <asm/pgtable-hwdef.h> + + +#include <asm/tlbflush.h> + +#ifdef CONFIG_ARM_LPAE +#include <asm/pgtable-3level.h> +#else +#include <asm/pgtable-2level.h> +#endif + +/* + * 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. ;) + */ +#define VMALLOC_OFFSET (8*1024*1024) +#define VMALLOC_START (((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1)) +#define VMALLOC_END 0xff800000UL + +#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 * 2) + +/* + * Use TASK_SIZE as the ceiling argument for free_pgtables() and + * free_pgd_range() to avoid freeing the modules pmd when LPAE is enabled (pmd + * page shared between user and kernel). + */ +#ifdef CONFIG_ARM_LPAE +#define USER_PGTABLES_CEILING TASK_SIZE +#endif + +/* + * 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 | L_PTE_NONE) +#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 | L_PTE_NONE) +#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) + +#define pgprot_device(prot) \ + __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_DEV_SHARED | L_PTE_SHARED | L_PTE_DIRTY | L_PTE_XN) + +#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__ + +extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; + +#define pmd_none(pmd) (!pmd_val(pmd)) + +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)) + +#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 pte_clear(mm,addr,ptep) set_pte_ext(ptep, __pte(0), 0) + +#define pte_isset(pte, val) ((u32)(val) == (val) ? pte_val(pte) & (val) \ + : !!(pte_val(pte) & (val))) +#define pte_isclear(pte, val) (!(pte_val(pte) & (val))) + +#define pte_none(pte) (!pte_val(pte)) +#define pte_present(pte) (pte_isset((pte), L_PTE_PRESENT)) +#define pte_valid(pte) (pte_isset((pte), L_PTE_VALID)) +#define pte_accessible(mm, pte) (mm_tlb_flush_pending(mm) ? pte_present(pte) : pte_valid(pte)) +#define pte_write(pte) (pte_isclear((pte), L_PTE_RDONLY)) +#define pte_dirty(pte) (pte_isset((pte), L_PTE_DIRTY)) +#define pte_young(pte) (pte_isset((pte), L_PTE_YOUNG)) +#define pte_exec(pte) (pte_isclear((pte), L_PTE_XN)) + +#define pte_valid_user(pte) \ + (pte_valid(pte) && pte_isset((pte), L_PTE_USER) && pte_young(pte)) + +static inline bool pte_access_permitted(pte_t pte, bool write) +{ + pteval_t mask = L_PTE_PRESENT | L_PTE_USER; + pteval_t needed = mask; + + if (write) + mask |= L_PTE_RDONLY; + + return (pte_val(pte) & mask) == needed; +} +#define pte_access_permitted pte_access_permitted + +#if __LINUX_ARM_ARCH__ < 6 +static inline void __sync_icache_dcache(pte_t pteval) +{ +} +#else +extern void __sync_icache_dcache(pte_t pteval); +#endif + +void set_pte_at(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, pte_t pteval); + +static inline pte_t clear_pte_bit(pte_t pte, pgprot_t prot) +{ + pte_val(pte) &= ~pgprot_val(prot); + return pte; +} + +static inline pte_t set_pte_bit(pte_t pte, pgprot_t prot) +{ + pte_val(pte) |= pgprot_val(prot); + return pte; +} + +static inline pte_t pte_wrprotect(pte_t pte) +{ + return set_pte_bit(pte, __pgprot(L_PTE_RDONLY)); +} + +static inline pte_t pte_mkwrite(pte_t pte) +{ + return clear_pte_bit(pte, __pgprot(L_PTE_RDONLY)); +} + +static inline pte_t pte_mkclean(pte_t pte) +{ + return clear_pte_bit(pte, __pgprot(L_PTE_DIRTY)); +} + +static inline pte_t pte_mkdirty(pte_t pte) +{ + return set_pte_bit(pte, __pgprot(L_PTE_DIRTY)); +} + +static inline pte_t pte_mkold(pte_t pte) +{ + return clear_pte_bit(pte, __pgprot(L_PTE_YOUNG)); +} + +static inline pte_t pte_mkyoung(pte_t pte) +{ + return set_pte_bit(pte, __pgprot(L_PTE_YOUNG)); +} + +static inline pte_t pte_mkexec(pte_t pte) +{ + return clear_pte_bit(pte, __pgprot(L_PTE_XN)); +} + +static inline pte_t pte_mknexec(pte_t pte) +{ + return set_pte_bit(pte, __pgprot(L_PTE_XN)); +} + +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 | + L_PTE_NONE | L_PTE_VALID; + 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 + * + * This gives us up to 31 swap files and 128GB per swap file. Note that + * the offset field is always non-zero. + */ +#define __SWP_TYPE_SHIFT 2 +#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) + +/* 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) + +/* + * We provide our own arch_get_unmapped_area to cope with VIPT caches. + */ +#define HAVE_ARCH_UNMAPPED_AREA +#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN + +#endif /* !__ASSEMBLY__ */ + +#endif /* CONFIG_MMU */ + +#endif /* _ASMARM_PGTABLE_H */ |