/* SPDX-License-Identifier: GPL-2.0 */
#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.
 *
 * 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_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 */

#define _PAGE_EXT_WIRED         0x4000  /* software: Wire TLB entry */

/* Wrapper for extended mode pgprot twiddling */
#define _PAGE_EXT(x)            ((unsigned long long)(x) << 32)

#ifdef CONFIG_X2TLB
#define _PAGE_PCC_MASK  0x00000000      /* No legacy PTEA support */
#else

/* 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 */

#define _PAGE_PCC_MASK  0xe0000001

/* 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_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_PR_MASK | _PAGE_SZ_MASK)
#else
#define _PAGE_CLEAR_FLAGS       (_PAGE_PROTNONE | _PAGE_ACCESSED)
#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
# define _PAGE_WIRED    (_PAGE_EXT(_PAGE_EXT_WIRED))
#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
# define _PAGE_WIRED    (0)
#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 across pgprot changes.
 */
#define _PAGE_CHG_MASK \
        (PTE_MASK | _PAGE_ACCESSED | _PAGE_CACHABLE | \
         _PAGE_DIRTY | _PAGE_SPECIAL)

#ifndef __ASSEMBLER__

#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(0)

#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 /* __ASSEMBLER__ */

#ifndef __ASSEMBLER__

/*
 * 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

/*
 * (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_SHIFT   PAGE_SHIFT
#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, ptep) set_pte(ptep, __pte(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_special(pte)        ((pte).pte_low & _PAGE_SPECIAL)

#ifdef CONFIG_X2TLB
#define pte_write(pte) \
        ((pte).pte_high & (_PAGE_EXT_USER_WRITE | _PAGE_EXT_KERN_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 | _PAGE_EXT_KERN_WRITE));
PTE_BIT_FUNC(high, mkwrite_novma, |= _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_novma, |= _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);

/*
 * 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

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;
}

static inline unsigned long pmd_page_vaddr(pmd_t pmd)
{
        return (unsigned long)pmd_val(pmd);
}

#define pmd_pfn(pmd)            (__pa(pmd_val(pmd)) >> PAGE_SHIFT)
#define pmd_page(pmd)           (virt_to_page(pmd_val(pmd)))

#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/decode swap entries and swap PTEs. Swap PTEs are all PTEs that
 * are !pte_none() && !pte_present().
 *
 * Constraints:
 *      _PAGE_PRESENT at bit 8
 *      _PAGE_PROTNONE at bit 9
 *
 * For the normal case, we encode the swap type and offset into the swap PTE
 * such that bits 8 and 9 stay zero. For the 64-bit PTE case, we use the
 * upper 32 for the swap offset and swap type, following the same approach as
 * x86 PAE. This keeps the logic quite simple.
 *
 * 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..
 */

#ifdef CONFIG_X2TLB
/*
 * Format of swap PTEs:
 *
 *   6 6 6 6 5 5 5 5 5 5 5 5 5 5 4 4 4 4 4 4 4 4 4 4 3 3 3 3 3 3 3 3
 *   3 2 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
 *   <--------------------- offset ----------------------> < type ->
 *
 *   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
 *   <------------------- zeroes --------------------> E 0 0 0 0 0 0
 */
#define __swp_type(x)                   ((x).val & 0x1f)
#define __swp_offset(x)                 ((x).val >> 5)
#define __swp_entry(type, offset)       ((swp_entry_t){ ((type) & 0x1f) | (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 })

#else
/*
 * Format of swap PTEs:
 *
 *   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 ----------------> 0 0 0 0 E < type -> 0
 *
 *   E is the exclusive marker that is not stored in swap entries.
 */
#define __swp_type(x)                   ((x).val & 0x1f)
#define __swp_offset(x)                 ((x).val >> 10)
#define __swp_entry(type, offset)       ((swp_entry_t){((type) & 0x1f) | (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 })
#endif

/* In both cases, we borrow bit 6 to store the exclusive marker in swap PTEs. */
#define _PAGE_SWP_EXCLUSIVE     _PAGE_USER

static inline bool pte_swp_exclusive(pte_t pte)
{
        return pte.pte_low & _PAGE_SWP_EXCLUSIVE;
}

PTE_BIT_FUNC(low, swp_mkexclusive, |= _PAGE_SWP_EXCLUSIVE);
PTE_BIT_FUNC(low, swp_clear_exclusive, &= ~_PAGE_SWP_EXCLUSIVE);

#endif /* __ASSEMBLER__ */
#endif /* __ASM_SH_PGTABLE_32_H */