Viewing file:  pgtable.h (11.71 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
#ifndef _I386_PGTABLE_H
#define _I386_PGTABLE_H
#include <linux/config.h>
/*
* 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 <asm/processor.h>
#include <asm/fixmap.h>
#include <linux/threads.h>
#ifndef _I386_BITOPS_H
#include <asm/bitops.h>
#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 <asm/pgtable-3level.h>
/*
* Need to initialise the X86 PAE caches
*/
extern void pgtable_cache_init(void);
#else
# include <asm/pgtable-2level.h>
/*
* No page table caches to initialise
*/
#define pgtable_cache_init() do { } while (0)
#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))
#if CONFIG_HIGHMEM
# define VMALLOC_END (PKMAP_BASE-2*PAGE_SIZE)
#else
# define VMALLOC_END (FIXADDR_START-2*PAGE_SIZE)
#endif
/*
* 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];
#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_set_wrprotect(pte_t *ptep) { clear_bit(_PAGE_BIT_RW, ptep); }
static inline void ptep_mkdirty(pte_t *ptep) { set_bit(_PAGE_BIT_DIRTY, 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 */
|