kernel-fxtec-pro1x/arch/sh/include/asm/pgtable_32.h
Michael Trimarchi 6503fe4a65 sh: Better description of SH-4 PTEA register update.
Signed-off-by: Michael Trimarchi <trimarchimichael@yahoo.it>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-20 13:27:44 +09:00

493 lines
17 KiB
C

#ifndef __ASM_SH_PGTABLE_32_H
#define __ASM_SH_PGTABLE_32_H
/*
* 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, and bit 11 is used for _PAGE_SPECIAL.
*
* - On 29 bit platforms, bits 31 to 29 are used for the space attributes
* and timing control which (together with bit 0) are moved into the
* old-style PTEA on the parts that support it.
*
* 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 */
#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) */
#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? */
#define _PAGE_SPECIAL 0x800 /* software: special page */
#define _PAGE_SZ_MASK (_PAGE_SZ0 | _PAGE_SZ1)
#define _PAGE_PR_MASK (_PAGE_RW | _PAGE_USER)
/* 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 */
#define _PAGE_EXT(x) ((unsigned long long)(x) << 32)
/* 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 */
#ifndef CONFIG_X2TLB
/* copy the ptea attributes */
static inline unsigned long copy_ptea_attributes(unsigned long x)
{
return ((x >> 28) & 0xe) | (x & 0x1);
}
#endif
/* Mask which drops unused bits from the PTEL value */
#if defined(CONFIG_CPU_SH3)
#define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE | _PAGE_ACCESSED| \
_PAGE_FILE | _PAGE_SZ1 | \
_PAGE_HW_SHARED)
#elif defined(CONFIG_X2TLB)
/* Get rid of the legacy PR/SZ bits when using extended mode */
#define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE | _PAGE_ACCESSED | \
_PAGE_FILE | _PAGE_PR_MASK | _PAGE_SZ_MASK)
#else
#define _PAGE_CLEAR_FLAGS (_PAGE_PROTNONE | _PAGE_ACCESSED | _PAGE_FILE)
#endif
#define _PAGE_FLAGS_HARDWARE_MASK (PHYS_ADDR_MASK & ~(_PAGE_CLEAR_FLAGS))
/* Hardware flags, page size encoding */
#if !defined(CONFIG_MMU)
# define _PAGE_FLAGS_HARD 0ULL
#elif 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
/*
* Mask of bits that are to be preserved accross pgprot changes.
*/
#define _PAGE_CHG_MASK \
(PTE_MASK | _PAGE_ACCESSED | _PAGE_CACHABLE | \
_PAGE_DIRTY | _PAGE_SPECIAL)
#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_KERN_READ | \
_PAGE_EXT_KERN_WRITE | \
_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_KERN_EXEC | \
_PAGE_EXT_KERN_READ | \
_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_KERN_READ | \
_PAGE_EXT_USER_READ))
#define PAGE_WRITEONLY __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
_PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
_PAGE_EXT(_PAGE_EXT_KERN_WRITE | \
_PAGE_EXT_USER_WRITE))
#define PAGE_RWX __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
_PAGE_CACHABLE | _PAGE_FLAGS_HARD | \
_PAGE_EXT(_PAGE_EXT_KERN_WRITE | \
_PAGE_EXT_KERN_READ | \
_PAGE_EXT_KERN_EXEC | \
_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(slot, type) \
__pgprot(0)
#endif
#endif /* __ASSEMBLY__ */
#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 pfn_pte(pfn, prot) \
__pte(((unsigned long long)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
#define pfn_pmd(pfn, prot) \
__pmd(((unsigned long long)(pfn) << PAGE_SHIFT) | pgprot_val(prot))
#define pte_none(x) (!pte_val(x))
#define pte_present(x) ((x).pte_low & (_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) pfn_to_page(pte_pfn(x))
/*
* The following only work if pte_present() is true.
* Undefined behaviour if not..
*/
#define pte_not_present(pte) (!((pte).pte_low & _PAGE_PRESENT))
#define pte_dirty(pte) ((pte).pte_low & _PAGE_DIRTY)
#define pte_young(pte) ((pte).pte_low & _PAGE_ACCESSED)
#define pte_file(pte) ((pte).pte_low & _PAGE_FILE)
#define pte_special(pte) ((pte).pte_low & _PAGE_SPECIAL)
#ifdef CONFIG_X2TLB
#define pte_write(pte) ((pte).pte_high & _PAGE_EXT_USER_WRITE)
#else
#define pte_write(pte) ((pte).pte_low & _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);
PTE_BIT_FUNC(low, mkspecial, |= _PAGE_SPECIAL);
#define __HAVE_ARCH_PTE_SPECIAL
/*
* Macro and implementation to make a page protection as uncachable.
*/
#define pgprot_writecombine(prot) \
__pgprot(pgprot_val(prot) & ~_PAGE_CACHABLE)
#define pgprot_noncached pgprot_writecombine
/*
* 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)
{
pte.pte_low &= _PAGE_CHG_MASK;
pte.pte_low |= pgprot_val(newprot);
#ifdef CONFIG_X2TLB
pte.pte_high |= pgprot_val(newprot) >> 32;
#endif
return pte;
}
#define pmd_page_vaddr(pmd) ((unsigned long)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)
#define pgd_ERROR(e) \
printk("%s:%d: bad pgd %016llx.\n", __FILE__, __LINE__, pgd_val(e))
#else
#define pte_ERROR(e) \
printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
#define pgd_ERROR(e) \
printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
#endif
/*
* 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
#endif /* __ASSEMBLY__ */
#endif /* __ASM_SH_PGTABLE_32_H */