linux-hardened/include/asm-sh/pgtable.h
Paul Mundt f0b859e3d6 sh: Reclaim beginning of P3 space for vmalloc area.
The first 1MB of P3 space was reserved and used for page colouring,
as we've reworked that to use fixmaps, we can reclaim the space and
hand it back to VMALLOC_START.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-07-25 10:43:47 +09:00

577 lines
19 KiB
C

/*
* This file contains the functions and defines necessary to modify and
* use the SuperH page table tree.
*
* Copyright (C) 1999 Niibe Yutaka
* Copyright (C) 2002 - 2005 Paul Mundt
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file "COPYING" in the main directory of this
* archive for more details.
*/
#ifndef __ASM_SH_PGTABLE_H
#define __ASM_SH_PGTABLE_H
#include <asm-generic/pgtable-nopmd.h>
#include <asm/page.h>
#ifndef __ASSEMBLY__
#include <asm/addrspace.h>
#include <asm/fixmap.h>
/*
* ZERO_PAGE is a global shared page that is always zero: used
* for zero-mapped memory areas etc..
*/
extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
#endif /* !__ASSEMBLY__ */
/*
* traditional two-level paging structure
*/
/* PTE bits */
#ifdef CONFIG_X2TLB
# define PTE_MAGNITUDE 3 /* 64-bit PTEs on extended mode SH-X2 TLB */
#else
# define PTE_MAGNITUDE 2 /* 32-bit PTEs */
#endif
#define PTE_SHIFT PAGE_SHIFT
#define PTE_BITS (PTE_SHIFT - PTE_MAGNITUDE)
/* PGD bits */
#define PGDIR_SHIFT (PTE_SHIFT + PTE_BITS)
#define PGDIR_BITS (32 - PGDIR_SHIFT)
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
#define PGDIR_MASK (~(PGDIR_SIZE-1))
/* Entries per level */
#define PTRS_PER_PTE (PAGE_SIZE / (1 << PTE_MAGNITUDE))
#define PTRS_PER_PGD (PAGE_SIZE / 4)
#define USER_PTRS_PER_PGD (TASK_SIZE/PGDIR_SIZE)
#define FIRST_USER_ADDRESS 0
#define PTE_PHYS_MASK (0x20000000 - PAGE_SIZE)
#define VMALLOC_START (P3SEG)
#define VMALLOC_END (FIXADDR_START-2*PAGE_SIZE)
/*
* Linux PTEL encoding.
*
* Hardware and software bit definitions for the PTEL value (see below for
* notes on SH-X2 MMUs and 64-bit PTEs):
*
* - Bits 0 and 7 are reserved on SH-3 (_PAGE_WT and _PAGE_SZ1 on SH-4).
*
* - Bit 1 is the SH-bit, but is unused on SH-3 due to an MMU bug (the
* hardware PTEL value can't have the SH-bit set when MMUCR.IX is set,
* which is the default in cpu-sh3/mmu_context.h:MMU_CONTROL_INIT).
*
* In order to keep this relatively clean, do not use these for defining
* SH-3 specific flags until all of the other unused bits have been
* exhausted.
*
* - Bit 9 is reserved by everyone and used by _PAGE_PROTNONE.
*
* - Bits 10 and 11 are low bits of the PPN that are reserved on >= 4K pages.
* Bit 10 is used for _PAGE_ACCESSED, bit 11 remains unused.
*
* - Bits 31, 30, and 29 remain unused by everyone and can be used for future
* software flags, although care must be taken to update _PAGE_CLEAR_FLAGS.
*
* XXX: Leave the _PAGE_FILE and _PAGE_WT overhaul for a rainy day.
*
* SH-X2 MMUs and extended PTEs
*
* SH-X2 supports an extended mode TLB with split data arrays due to the
* number of bits needed for PR and SZ (now EPR and ESZ) encodings. The PR and
* SZ bit placeholders still exist in data array 1, but are implemented as
* reserved bits, with the real logic existing in data array 2.
*
* The downside to this is that we can no longer fit everything in to a 32-bit
* PTE encoding, so a 64-bit pte_t is necessary for these parts. On the plus
* side, this gives us quite a few spare bits to play with for future usage.
*/
/* Legacy and compat mode bits */
#define _PAGE_WT 0x001 /* WT-bit on SH-4, 0 on SH-3 */
#define _PAGE_HW_SHARED 0x002 /* SH-bit : shared among processes */
#define _PAGE_DIRTY 0x004 /* D-bit : page changed */
#define _PAGE_CACHABLE 0x008 /* C-bit : cachable */
#ifndef CONFIG_X2TLB
# define _PAGE_SZ0 0x010 /* SZ0-bit : Size of page */
# define _PAGE_RW 0x020 /* PR0-bit : write access allowed */
# define _PAGE_USER 0x040 /* PR1-bit : user space access allowed*/
# define _PAGE_SZ1 0x080 /* SZ1-bit : Size of page (on SH-4) */
#endif
#define _PAGE_PRESENT 0x100 /* V-bit : page is valid */
#define _PAGE_PROTNONE 0x200 /* software: if not present */
#define _PAGE_ACCESSED 0x400 /* software: page referenced */
#define _PAGE_FILE _PAGE_WT /* software: pagecache or swap? */
/* Extended mode bits */
#define _PAGE_EXT_ESZ0 0x0010 /* ESZ0-bit: Size of page */
#define _PAGE_EXT_ESZ1 0x0020 /* ESZ1-bit: Size of page */
#define _PAGE_EXT_ESZ2 0x0040 /* ESZ2-bit: Size of page */
#define _PAGE_EXT_ESZ3 0x0080 /* ESZ3-bit: Size of page */
#define _PAGE_EXT_USER_EXEC 0x0100 /* EPR0-bit: User space executable */
#define _PAGE_EXT_USER_WRITE 0x0200 /* EPR1-bit: User space writable */
#define _PAGE_EXT_USER_READ 0x0400 /* EPR2-bit: User space readable */
#define _PAGE_EXT_KERN_EXEC 0x0800 /* EPR3-bit: Kernel space executable */
#define _PAGE_EXT_KERN_WRITE 0x1000 /* EPR4-bit: Kernel space writable */
#define _PAGE_EXT_KERN_READ 0x2000 /* EPR5-bit: Kernel space readable */
/* Wrapper for extended mode pgprot twiddling */
#ifdef CONFIG_X2TLB
# define _PAGE_EXT(x) ((unsigned long long)(x) << 32)
#else
# define _PAGE_EXT(x) (0)
#endif
/* software: moves to PTEA.TC (Timing Control) */
#define _PAGE_PCC_AREA5 0x00000000 /* use BSC registers for area5 */
#define _PAGE_PCC_AREA6 0x80000000 /* use BSC registers for area6 */
/* software: moves to PTEA.SA[2:0] (Space Attributes) */
#define _PAGE_PCC_IODYN 0x00000001 /* IO space, dynamically sized bus */
#define _PAGE_PCC_IO8 0x20000000 /* IO space, 8 bit bus */
#define _PAGE_PCC_IO16 0x20000001 /* IO space, 16 bit bus */
#define _PAGE_PCC_COM8 0x40000000 /* Common Memory space, 8 bit bus */
#define _PAGE_PCC_COM16 0x40000001 /* Common Memory space, 16 bit bus */
#define _PAGE_PCC_ATR8 0x60000000 /* Attribute Memory space, 8 bit bus */
#define _PAGE_PCC_ATR16 0x60000001 /* Attribute Memory space, 6 bit bus */
/* Mask which drops unused bits from the PTEL value */
#ifdef CONFIG_CPU_SH3
#define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE | _PAGE_ACCESSED| \
_PAGE_FILE | _PAGE_SZ1 | \
_PAGE_HW_SHARED)
#else
#define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE | _PAGE_ACCESSED | _PAGE_FILE)
#endif
#define _PAGE_FLAGS_HARDWARE_MASK (0x1fffffff & ~(_PAGE_CLEAR_FLAGS))
/* Hardware flags, page size encoding */
#if defined(CONFIG_X2TLB)
# if defined(CONFIG_PAGE_SIZE_4KB)
# define _PAGE_FLAGS_HARD _PAGE_EXT(_PAGE_EXT_ESZ0)
# elif defined(CONFIG_PAGE_SIZE_8KB)
# define _PAGE_FLAGS_HARD _PAGE_EXT(_PAGE_EXT_ESZ1)
# elif defined(CONFIG_PAGE_SIZE_64KB)
# define _PAGE_FLAGS_HARD _PAGE_EXT(_PAGE_EXT_ESZ2)
# endif
#else
# if defined(CONFIG_PAGE_SIZE_4KB)
# define _PAGE_FLAGS_HARD _PAGE_SZ0
# elif defined(CONFIG_PAGE_SIZE_64KB)
# define _PAGE_FLAGS_HARD _PAGE_SZ1
# endif
#endif
#if defined(CONFIG_X2TLB)
# if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
# define _PAGE_SZHUGE (_PAGE_EXT_ESZ2)
# elif defined(CONFIG_HUGETLB_PAGE_SIZE_256K)
# define _PAGE_SZHUGE (_PAGE_EXT_ESZ0 | _PAGE_EXT_ESZ2)
# elif defined(CONFIG_HUGETLB_PAGE_SIZE_1MB)
# define _PAGE_SZHUGE (_PAGE_EXT_ESZ0 | _PAGE_EXT_ESZ1 | _PAGE_EXT_ESZ2)
# elif defined(CONFIG_HUGETLB_PAGE_SIZE_4MB)
# define _PAGE_SZHUGE (_PAGE_EXT_ESZ3)
# elif defined(CONFIG_HUGETLB_PAGE_SIZE_64MB)
# define _PAGE_SZHUGE (_PAGE_EXT_ESZ2 | _PAGE_EXT_ESZ3)
# endif
#else
# if defined(CONFIG_HUGETLB_PAGE_SIZE_64K)
# define _PAGE_SZHUGE (_PAGE_SZ1)
# elif defined(CONFIG_HUGETLB_PAGE_SIZE_1MB)
# define _PAGE_SZHUGE (_PAGE_SZ0 | _PAGE_SZ1)
# endif
#endif
/*
* Stub out _PAGE_SZHUGE if we don't have a good definition for it,
* to make pte_mkhuge() happy.
*/
#ifndef _PAGE_SZHUGE
# define _PAGE_SZHUGE (_PAGE_FLAGS_HARD)
#endif
#define _PAGE_CHG_MASK \
(PTE_MASK | _PAGE_ACCESSED | _PAGE_CACHABLE | _PAGE_DIRTY)
#ifndef __ASSEMBLY__
#if defined(CONFIG_X2TLB) /* SH-X2 TLB */
#define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_CACHABLE | \
_PAGE_ACCESSED | _PAGE_FLAGS_HARD)
#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
_PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
_PAGE_EXT(_PAGE_EXT_USER_READ | \
_PAGE_EXT_USER_WRITE))
#define PAGE_EXECREAD __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
_PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
_PAGE_EXT(_PAGE_EXT_USER_EXEC | \
_PAGE_EXT_USER_READ))
#define PAGE_COPY PAGE_EXECREAD
#define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
_PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
_PAGE_EXT(_PAGE_EXT_USER_READ))
#define PAGE_WRITEONLY __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
_PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
_PAGE_EXT(_PAGE_EXT_USER_WRITE))
#define PAGE_RWX __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
_PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
_PAGE_EXT(_PAGE_EXT_USER_WRITE | \
_PAGE_EXT_USER_READ | \
_PAGE_EXT_USER_EXEC))
#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \
_PAGE_DIRTY | _PAGE_ACCESSED | \
_PAGE_HW_SHARED | _PAGE_FLAGS_HARD | \
_PAGE_EXT(_PAGE_EXT_KERN_READ | \
_PAGE_EXT_KERN_WRITE | \
_PAGE_EXT_KERN_EXEC))
#define PAGE_KERNEL_NOCACHE \
__pgprot(_PAGE_PRESENT | _PAGE_DIRTY | \
_PAGE_ACCESSED | _PAGE_HW_SHARED | \
_PAGE_FLAGS_HARD | \
_PAGE_EXT(_PAGE_EXT_KERN_READ | \
_PAGE_EXT_KERN_WRITE | \
_PAGE_EXT_KERN_EXEC))
#define PAGE_KERNEL_RO __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \
_PAGE_DIRTY | _PAGE_ACCESSED | \
_PAGE_HW_SHARED | _PAGE_FLAGS_HARD | \
_PAGE_EXT(_PAGE_EXT_KERN_READ | \
_PAGE_EXT_KERN_EXEC))
#define PAGE_KERNEL_PCC(slot, type) \
__pgprot(_PAGE_PRESENT | _PAGE_DIRTY | \
_PAGE_ACCESSED | _PAGE_FLAGS_HARD | \
_PAGE_EXT(_PAGE_EXT_KERN_READ | \
_PAGE_EXT_KERN_WRITE | \
_PAGE_EXT_KERN_EXEC) \
(slot ? _PAGE_PCC_AREA5 : _PAGE_PCC_AREA6) | \
(type))
#elif defined(CONFIG_MMU) /* SH-X TLB */
#define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_CACHABLE | \
_PAGE_ACCESSED | _PAGE_FLAGS_HARD)
#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | \
_PAGE_CACHABLE | _PAGE_ACCESSED | \
_PAGE_FLAGS_HARD)
#define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_CACHABLE | \
_PAGE_ACCESSED | _PAGE_FLAGS_HARD)
#define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_CACHABLE | \
_PAGE_ACCESSED | _PAGE_FLAGS_HARD)
#define PAGE_EXECREAD PAGE_READONLY
#define PAGE_RWX PAGE_SHARED
#define PAGE_WRITEONLY PAGE_SHARED
#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_CACHABLE | \
_PAGE_DIRTY | _PAGE_ACCESSED | \
_PAGE_HW_SHARED | _PAGE_FLAGS_HARD)
#define PAGE_KERNEL_NOCACHE \
__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | \
_PAGE_ACCESSED | _PAGE_HW_SHARED | \
_PAGE_FLAGS_HARD)
#define PAGE_KERNEL_RO __pgprot(_PAGE_PRESENT | _PAGE_CACHABLE | \
_PAGE_DIRTY | _PAGE_ACCESSED | \
_PAGE_HW_SHARED | _PAGE_FLAGS_HARD)
#define PAGE_KERNEL_PCC(slot, type) \
__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | \
_PAGE_ACCESSED | _PAGE_FLAGS_HARD | \
(slot ? _PAGE_PCC_AREA5 : _PAGE_PCC_AREA6) | \
(type))
#else /* no mmu */
#define PAGE_NONE __pgprot(0)
#define PAGE_SHARED __pgprot(0)
#define PAGE_COPY __pgprot(0)
#define PAGE_EXECREAD __pgprot(0)
#define PAGE_RWX __pgprot(0)
#define PAGE_READONLY __pgprot(0)
#define PAGE_WRITEONLY __pgprot(0)
#define PAGE_KERNEL __pgprot(0)
#define PAGE_KERNEL_NOCACHE __pgprot(0)
#define PAGE_KERNEL_RO __pgprot(0)
#define PAGE_KERNEL_PCC __pgprot(0)
#endif
#endif /* __ASSEMBLY__ */
/*
* SH-X and lower (legacy) SuperH parts (SH-3, SH-4, some SH-4A) can't do page
* protection for execute, and considers it the same as a read. Also, write
* permission implies read permission. This is the closest we can get..
*
* SH-X2 (SH7785) and later parts take this to the opposite end of the extreme,
* not only supporting separate execute, read, and write bits, but having
* completely separate permission bits for user and kernel space.
*/
/*xwr*/
#define __P000 PAGE_NONE
#define __P001 PAGE_READONLY
#define __P010 PAGE_COPY
#define __P011 PAGE_COPY
#define __P100 PAGE_EXECREAD
#define __P101 PAGE_EXECREAD
#define __P110 PAGE_COPY
#define __P111 PAGE_COPY
#define __S000 PAGE_NONE
#define __S001 PAGE_READONLY
#define __S010 PAGE_WRITEONLY
#define __S011 PAGE_SHARED
#define __S100 PAGE_EXECREAD
#define __S101 PAGE_EXECREAD
#define __S110 PAGE_RWX
#define __S111 PAGE_RWX
#ifndef __ASSEMBLY__
/*
* Certain architectures need to do special things when PTEs
* within a page table are directly modified. Thus, the following
* hook is made available.
*/
#ifdef CONFIG_X2TLB
static inline void set_pte(pte_t *ptep, pte_t pte)
{
ptep->pte_high = pte.pte_high;
smp_wmb();
ptep->pte_low = pte.pte_low;
}
#else
#define set_pte(pteptr, pteval) (*(pteptr) = pteval)
#endif
#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
/*
* (pmds are folded into pgds so this doesn't get actually called,
* but the define is needed for a generic inline function.)
*/
#define set_pmd(pmdptr, pmdval) (*(pmdptr) = pmdval)
#define pte_pfn(x) ((unsigned long)(((x).pte_low >> PAGE_SHIFT)))
#define pfn_pte(pfn, prot) __pte(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
#define pfn_pmd(pfn, prot) __pmd(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
#define pte_none(x) (!pte_val(x))
#define pte_present(x) (pte_val(x) & (_PAGE_PRESENT | _PAGE_PROTNONE))
#define pte_clear(mm,addr,xp) do { set_pte_at(mm, addr, xp, __pte(0)); } while (0)
#define pmd_none(x) (!pmd_val(x))
#define pmd_present(x) (pmd_val(x))
#define pmd_clear(xp) do { set_pmd(xp, __pmd(0)); } while (0)
#define pmd_bad(x) (pmd_val(x) & ~PAGE_MASK)
#define pages_to_mb(x) ((x) >> (20-PAGE_SHIFT))
#define pte_page(x) phys_to_page(pte_val(x)&PTE_PHYS_MASK)
/*
* The following only work if pte_present() is true.
* Undefined behaviour if not..
*/
#define pte_not_present(pte) (!(pte_val(pte) & _PAGE_PRESENT))
#define pte_dirty(pte) (pte_val(pte) & _PAGE_DIRTY)
#define pte_young(pte) (pte_val(pte) & _PAGE_ACCESSED)
#define pte_file(pte) (pte_val(pte) & _PAGE_FILE)
#ifdef CONFIG_X2TLB
#define pte_write(pte) ((pte).pte_high & _PAGE_EXT_USER_WRITE)
#else
#define pte_write(pte) (pte_val(pte) & _PAGE_RW)
#endif
#define PTE_BIT_FUNC(h,fn,op) \
static inline pte_t pte_##fn(pte_t pte) { pte.pte_##h op; return pte; }
#ifdef CONFIG_X2TLB
/*
* We cheat a bit in the SH-X2 TLB case. As the permission bits are
* individually toggled (and user permissions are entirely decoupled from
* kernel permissions), we attempt to couple them a bit more sanely here.
*/
PTE_BIT_FUNC(high, wrprotect, &= ~_PAGE_EXT_USER_WRITE);
PTE_BIT_FUNC(high, mkwrite, |= _PAGE_EXT_USER_WRITE | _PAGE_EXT_KERN_WRITE);
PTE_BIT_FUNC(high, mkhuge, |= _PAGE_SZHUGE);
#else
PTE_BIT_FUNC(low, wrprotect, &= ~_PAGE_RW);
PTE_BIT_FUNC(low, mkwrite, |= _PAGE_RW);
PTE_BIT_FUNC(low, mkhuge, |= _PAGE_SZHUGE);
#endif
PTE_BIT_FUNC(low, mkclean, &= ~_PAGE_DIRTY);
PTE_BIT_FUNC(low, mkdirty, |= _PAGE_DIRTY);
PTE_BIT_FUNC(low, mkold, &= ~_PAGE_ACCESSED);
PTE_BIT_FUNC(low, mkyoung, |= _PAGE_ACCESSED);
/*
* Macro and implementation to make a page protection as uncachable.
*/
#define pgprot_noncached pgprot_noncached
static inline pgprot_t pgprot_noncached(pgprot_t _prot)
{
unsigned long prot = pgprot_val(_prot);
prot &= ~_PAGE_CACHABLE;
return __pgprot(prot);
}
#define pgprot_writecombine(prot) __pgprot(pgprot_val(prot) & ~_PAGE_CACHABLE)
/*
* Conversion functions: convert a page and protection to a page entry,
* and a page entry and page directory to the page they refer to.
*
* extern pte_t mk_pte(struct page *page, pgprot_t pgprot)
*/
#define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{
set_pte(&pte, __pte((pte_val(pte) & _PAGE_CHG_MASK) |
pgprot_val(newprot)));
return pte;
}
#define pmd_page_vaddr(pmd) pmd_val(pmd)
#define pmd_page(pmd) (virt_to_page(pmd_val(pmd)))
/* to find an entry in a page-table-directory. */
#define pgd_index(address) (((address) >> PGDIR_SHIFT) & (PTRS_PER_PGD-1))
#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)
/* Find an entry in the third-level page table.. */
#define pte_index(address) \
((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
#define pte_offset_kernel(dir, address) \
((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(address))
#define pte_offset_map(dir, address) pte_offset_kernel(dir, address)
#define pte_offset_map_nested(dir, address) pte_offset_kernel(dir, address)
#define pte_unmap(pte) do { } while (0)
#define pte_unmap_nested(pte) do { } while (0)
#ifdef CONFIG_X2TLB
#define pte_ERROR(e) \
printk("%s:%d: bad pte %p(%08lx%08lx).\n", __FILE__, __LINE__, \
&(e), (e).pte_high, (e).pte_low)
#else
#define pte_ERROR(e) \
printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
#endif
#define pgd_ERROR(e) \
printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
struct vm_area_struct;
extern void update_mmu_cache(struct vm_area_struct * vma,
unsigned long address, pte_t pte);
/*
* Encode and de-code a swap entry
*
* Constraints:
* _PAGE_FILE at bit 0
* _PAGE_PRESENT at bit 8
* _PAGE_PROTNONE at bit 9
*
* For the normal case, we encode the swap type into bits 0:7 and the
* swap offset into bits 10:30. For the 64-bit PTE case, we keep the
* preserved bits in the low 32-bits and use the upper 32 as the swap
* offset (along with a 5-bit type), following the same approach as x86
* PAE. This keeps the logic quite simple, and allows for a full 32
* PTE_FILE_MAX_BITS, as opposed to the 29-bits we're constrained with
* in the pte_low case.
*
* As is evident by the Alpha code, if we ever get a 64-bit unsigned
* long (swp_entry_t) to match up with the 64-bit PTEs, this all becomes
* much cleaner..
*
* NOTE: We should set ZEROs at the position of _PAGE_PRESENT
* and _PAGE_PROTNONE bits
*/
#ifdef CONFIG_X2TLB
#define __swp_type(x) ((x).val & 0x1f)
#define __swp_offset(x) ((x).val >> 5)
#define __swp_entry(type, offset) ((swp_entry_t){ (type) | (offset) << 5})
#define __pte_to_swp_entry(pte) ((swp_entry_t){ (pte).pte_high })
#define __swp_entry_to_pte(x) ((pte_t){ 0, (x).val })
/*
* Encode and decode a nonlinear file mapping entry
*/
#define pte_to_pgoff(pte) ((pte).pte_high)
#define pgoff_to_pte(off) ((pte_t) { _PAGE_FILE, (off) })
#define PTE_FILE_MAX_BITS 32
#else
#define __swp_type(x) ((x).val & 0xff)
#define __swp_offset(x) ((x).val >> 10)
#define __swp_entry(type, offset) ((swp_entry_t){(type) | (offset) <<10})
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) >> 1 })
#define __swp_entry_to_pte(x) ((pte_t) { (x).val << 1 })
/*
* Encode and decode a nonlinear file mapping entry
*/
#define PTE_FILE_MAX_BITS 29
#define pte_to_pgoff(pte) (pte_val(pte) >> 1)
#define pgoff_to_pte(off) ((pte_t) { ((off) << 1) | _PAGE_FILE })
#endif
typedef pte_t *pte_addr_t;
#define kern_addr_valid(addr) (1)
#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
remap_pfn_range(vma, vaddr, pfn, size, prot)
struct mm_struct;
/*
* No page table caches to initialise
*/
#define pgtable_cache_init() do { } while (0)
#ifndef CONFIG_MMU
extern unsigned int kobjsize(const void *objp);
#endif /* !CONFIG_MMU */
#if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
extern pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep);
#endif
extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
extern void paging_init(void);
#include <asm-generic/pgtable.h>
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_SH_PAGE_H */