#ifndef _I386_PGTABLE_H #define _I386_PGTABLE_H #include /* * The Linux memory management assumes a three-level page table setup. On * the i386, we use that, but "fold" the mid level into the top-level page * table, so that we physically have the same two-level page table as the * i386 mmu expects. * * This file contains the functions and defines necessary to modify and use * the i386 page table tree. */ #ifndef __ASSEMBLY__ #include #include #include #ifndef _I386_BITOPS_H #include #endif extern pgd_t swapper_pg_dir[1024]; extern void paging_init(void); /* Caches aren't brain-dead on the intel. */ #define flush_cache_all() do { } while (0) #define flush_cache_mm(mm) do { } while (0) #define flush_cache_range(mm, start, end) do { } while (0) #define flush_cache_page(vma, vmaddr) do { } while (0) #define flush_page_to_ram(page) do { } while (0) #define flush_dcache_page(page) do { } while (0) #define flush_icache_range(start, end) do { } while (0) #define flush_icache_page(vma,pg) do { } while (0) #define __flush_tlb() \ do { \ unsigned int tmpreg; \ \ __asm__ __volatile__( \ "movl %%cr3, %0; # flush TLB \n" \ "movl %0, %%cr3; \n" \ : "=r" (tmpreg) \ :: "memory"); \ } while (0) /* * Global pages have to be flushed a bit differently. Not a real * performance problem because this does not happen often. */ #define __flush_tlb_global() \ do { \ unsigned int tmpreg; \ \ __asm__ __volatile__( \ "movl %1, %%cr4; # turn off PGE \n" \ "movl %%cr3, %0; # flush TLB \n" \ "movl %0, %%cr3; \n" \ "movl %2, %%cr4; # turn PGE back on \n" \ : "=&r" (tmpreg) \ : "r" (mmu_cr4_features & ~X86_CR4_PGE), \ "r" (mmu_cr4_features) \ : "memory"); \ } while (0) extern unsigned long pgkern_mask; /* * Do not check the PGE bit unnecesserily if this is a PPro+ kernel. */ #ifdef CONFIG_X86_PGE # define __flush_tlb_all() __flush_tlb_global() #else # define __flush_tlb_all() \ do { \ if (cpu_has_pge) \ __flush_tlb_global(); \ else \ __flush_tlb(); \ } while (0) #endif #ifndef CONFIG_X86_INVLPG #define __flush_tlb_one(addr) __flush_tlb() #else #define __flush_tlb_one(addr) \ __asm__ __volatile__("invlpg %0": :"m" (*(char *) addr)) #endif /* * ZERO_PAGE is a global shared page that is always zero: used * for zero-mapped memory areas etc.. */ extern unsigned long empty_zero_page[1024]; #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page)) #endif /* !__ASSEMBLY__ */ /* * The Linux x86 paging architecture is 'compile-time dual-mode', it * implements both the traditional 2-level x86 page tables and the * newer 3-level PAE-mode page tables. */ #ifndef __ASSEMBLY__ #if CONFIG_X86_PAE # include #else # include #endif #endif #define __beep() asm("movb $0x3,%al; outb %al,$0x61") #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 USER_PTRS_PER_PGD (TASK_SIZE/PGDIR_SIZE) #define FIRST_USER_PGD_NR 0 #define USER_PGD_PTRS (PAGE_OFFSET >> PGDIR_SHIFT) #define KERNEL_PGD_PTRS (PTRS_PER_PGD-USER_PGD_PTRS) #define TWOLEVEL_PGDIR_SHIFT 22 #define BOOT_USER_PGD_PTRS (__PAGE_OFFSET >> TWOLEVEL_PGDIR_SHIFT) #define BOOT_KERNEL_PGD_PTRS (1024-BOOT_USER_PGD_PTRS) #ifndef __ASSEMBLY__ /* 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 + 2*VMALLOC_OFFSET-1) & \ ~(VMALLOC_OFFSET-1)) #define VMALLOC_VMADDR(x) ((unsigned long)(x)) #define VMALLOC_END (FIXADDR_START) /* * The 4MB page is guessing.. Detailed in the infamous "Chapter H" * of the Pentium details, but assuming intel did the straightforward * thing, this bit set in the page directory entry just means that * the page directory entry points directly to a 4MB-aligned block of * memory. */ #define _PAGE_BIT_PRESENT 0 #define _PAGE_BIT_RW 1 #define _PAGE_BIT_USER 2 #define _PAGE_BIT_PWT 3 #define _PAGE_BIT_PCD 4 #define _PAGE_BIT_ACCESSED 5 #define _PAGE_BIT_DIRTY 6 #define _PAGE_BIT_PSE 7 /* 4 MB (or 2MB) page, Pentium+, if present.. */ #define _PAGE_BIT_GLOBAL 8 /* Global TLB entry PPro+ */ #define _PAGE_PRESENT 0x001 #define _PAGE_RW 0x002 #define _PAGE_USER 0x004 #define _PAGE_PWT 0x008 #define _PAGE_PCD 0x010 #define _PAGE_ACCESSED 0x020 #define _PAGE_DIRTY 0x040 #define _PAGE_PSE 0x080 /* 4 MB (or 2MB) page, Pentium+, if present.. */ #define _PAGE_GLOBAL 0x100 /* Global TLB entry PPro+ */ #define _PAGE_PROTNONE 0x080 /* If not present */ #define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY) #define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY) #define _PAGE_CHG_MASK (PTE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY) #define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED) #define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED) #define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED) #define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED) #define __PAGE_KERNEL \ (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED) #define __PAGE_KERNEL_NOCACHE \ (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_PCD | _PAGE_ACCESSED) #define __PAGE_KERNEL_RO \ (_PAGE_PRESENT | _PAGE_DIRTY | _PAGE_ACCESSED) #ifdef CONFIG_X86_PGE # define MAKE_GLOBAL(x) __pgprot((x) | _PAGE_GLOBAL) #else # define MAKE_GLOBAL(x) \ ({ \ pgprot_t __ret; \ \ if (cpu_has_pge) \ __ret = __pgprot((x) | _PAGE_GLOBAL); \ else \ __ret = __pgprot(x); \ __ret; \ }) #endif #define PAGE_KERNEL MAKE_GLOBAL(__PAGE_KERNEL) #define PAGE_KERNEL_RO MAKE_GLOBAL(__PAGE_KERNEL_RO) #define PAGE_KERNEL_NOCACHE MAKE_GLOBAL(__PAGE_KERNEL_NOCACHE) /* * The i386 can't do page protection for execute, and considers that * the same are read. Also, write permissions imply read permissions. * This is the closest we can get.. */ #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 /* * Define this if things work differently on an i386 and an i486: * it will (on an i486) warn about kernel memory accesses that are * done without a 'verify_area(VERIFY_WRITE,..)' */ #undef TEST_VERIFY_AREA /* page table for 0-4MB for everybody */ extern unsigned long pg0[1024]; /* * Handling allocation failures during page table setup. */ extern void __handle_bad_pmd(pmd_t * pmd); extern void __handle_bad_pmd_kernel(pmd_t * pmd); #define pte_present(x) ((x).pte_low & (_PAGE_PRESENT | _PAGE_PROTNONE)) #define pte_clear(xp) do { set_pte(xp, __pte(0)); } while (0) #define pmd_none(x) (!pmd_val(x)) #define pmd_present(x) (pmd_val(x) & _PAGE_PRESENT) #define pmd_clear(xp) do { set_pmd(xp, __pmd(0)); } while (0) #define pmd_bad(x) ((pmd_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE) /* * Permanent address of a page. Obviously must never be * called on a highmem page. */ #define page_address(page) ((page)->virtual) #define pages_to_mb(x) ((x) >> (20-PAGE_SHIFT)) /* * The following only work if pte_present() is true. * Undefined behaviour if not.. */ static inline int pte_read(pte_t pte) { return (pte).pte_low & _PAGE_USER; } static inline int pte_exec(pte_t pte) { return (pte).pte_low & _PAGE_USER; } static inline int pte_dirty(pte_t pte) { return (pte).pte_low & _PAGE_DIRTY; } static inline int pte_young(pte_t pte) { return (pte).pte_low & _PAGE_ACCESSED; } static inline int pte_write(pte_t pte) { return (pte).pte_low & _PAGE_RW; } static inline pte_t pte_rdprotect(pte_t pte) { (pte).pte_low &= ~_PAGE_USER; return pte; } static inline pte_t pte_exprotect(pte_t pte) { (pte).pte_low &= ~_PAGE_USER; return pte; } static inline pte_t pte_mkclean(pte_t pte) { (pte).pte_low &= ~_PAGE_DIRTY; return pte; } static inline pte_t pte_mkold(pte_t pte) { (pte).pte_low &= ~_PAGE_ACCESSED; return pte; } static inline pte_t pte_wrprotect(pte_t pte) { (pte).pte_low &= ~_PAGE_RW; return pte; } static inline pte_t pte_mkread(pte_t pte) { (pte).pte_low |= _PAGE_USER; return pte; } static inline pte_t pte_mkexec(pte_t pte) { (pte).pte_low |= _PAGE_USER; return pte; } static inline pte_t pte_mkdirty(pte_t pte) { (pte).pte_low |= _PAGE_DIRTY; return pte; } static inline pte_t pte_mkyoung(pte_t pte) { (pte).pte_low |= _PAGE_ACCESSED; return pte; } static inline pte_t pte_mkwrite(pte_t pte) { (pte).pte_low |= _PAGE_RW; return pte; } static inline int ptep_test_and_clear_dirty(pte_t *ptep) { return test_and_clear_bit(_PAGE_BIT_DIRTY, ptep); } static inline int ptep_test_and_clear_young(pte_t *ptep) { return test_and_clear_bit(_PAGE_BIT_ACCESSED, ptep); } static inline void ptep_clear_wrprotect(pte_t *ptep) { clear_bit(_PAGE_BIT_RW, ptep); } static inline void ptep_mkdirty(pte_t *ptep) { set_bit(_PAGE_BIT_RW, ptep); } /* * Conversion functions: convert a page and protection to a page entry, * and a page entry and page directory to the page they refer to. */ #define mk_pte(page, pgprot) __mk_pte((page) - mem_map, (pgprot)) /* This takes a physical page address that is used by the remapping functions */ #define mk_pte_phys(physpage, pgprot) __mk_pte((physpage) >> PAGE_SHIFT, pgprot) static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) { pte.pte_low &= _PAGE_CHG_MASK; pte.pte_low |= pgprot_val(newprot); return pte; } #define page_pte(page) page_pte_prot(page, __pgprot(0)) #define pmd_page(pmd) \ ((unsigned long) __va(pmd_val(pmd) & PAGE_MASK)) /* to find an entry in a page-table-directory. */ #define pgd_index(address) ((address >> PGDIR_SHIFT) & (PTRS_PER_PGD-1)) #define __pgd_offset(address) pgd_index(address) #define pgd_offset(mm, address) ((mm)->pgd+pgd_index(address)) /* to find an entry in a kernel page-table-directory */ #define pgd_offset_k(address) pgd_offset(&init_mm, address) #define __pmd_offset(address) \ (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1)) /* Find an entry in the third-level page table.. */ #define __pte_offset(address) \ ((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) #define pte_offset(dir, address) ((pte_t *) pmd_page(*(dir)) + \ __pte_offset(address)) /* * The i386 doesn't have any external MMU info: the kernel page * tables contain all the necessary information. */ #define update_mmu_cache(vma,address,pte) do { } while (0) /* Encode and de-code a swap entry */ #define SWP_TYPE(x) (((x).val >> 1) & 0x3f) #define SWP_OFFSET(x) ((x).val >> 8) #define SWP_ENTRY(type, offset) ((swp_entry_t) { ((type) << 1) | ((offset) << 8) }) #define pte_to_swp_entry(pte) ((swp_entry_t) { (pte).pte_low }) #define swp_entry_to_pte(x) ((pte_t) { (x).val }) #endif /* !__ASSEMBLY__ */ /* Needs to be defined here and not in linux/mm.h, as it is arch dependent */ #define PageSkip(page) (0) #define kern_addr_valid(addr) (1) #define io_remap_page_range remap_page_range #endif /* _I386_PGTABLE_H */