/* 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 #include #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 #include #else #include #include #include #include #ifdef CONFIG_ARM_LPAE #include #else #include #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 */