2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-22 20:23:57 +08:00
linux-next/include/asm-parisc/pgtable.h
Nick Piggin 7e675137a8 mm: introduce pte_special pte bit
s390 for one, cannot implement VM_MIXEDMAP with pfn_valid, due to their memory
model (which is more dynamic than most).  Instead, they had proposed to
implement it with an additional path through vm_normal_page(), using a bit in
the pte to determine whether or not the page should be refcounted:

vm_normal_page()
{
	...
        if (unlikely(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP))) {
                if (vma->vm_flags & VM_MIXEDMAP) {
#ifdef s390
			if (!mixedmap_refcount_pte(pte))
				return NULL;
#else
                        if (!pfn_valid(pfn))
                                return NULL;
#endif
                        goto out;
                }
	...
}

This is fine, however if we are allowed to use a bit in the pte to determine
refcountedness, we can use that to _completely_ replace all the vma based
schemes.  So instead of adding more cases to the already complex vma-based
scheme, we can have a clearly seperate and simple pte-based scheme (and get
slightly better code generation in the process):

vm_normal_page()
{
#ifdef s390
	if (!mixedmap_refcount_pte(pte))
		return NULL;
	return pte_page(pte);
#else
	...
#endif
}

And finally, we may rather make this concept usable by any architecture rather
than making it s390 only, so implement a new type of pte state for this.
Unfortunately the old vma based code must stay, because some architectures may
not be able to spare pte bits.  This makes vm_normal_page a little bit more
ugly than we would like, but the 2 cases are clearly seperate.

So introduce a pte_special pte state, and use it in mm/memory.c.  It is
currently a noop for all architectures, so this doesn't actually result in any
compiled code changes to mm/memory.o.

BTW:
I haven't put vm_normal_page() into arch code as-per an earlier suggestion.
The reason is that, regardless of where vm_normal_page is actually
implemented, the *abstraction* is still exactly the same. Also, while it
depends on whether the architecture has pte_special or not, that is the
only two possible cases, and it really isn't an arch specific function --
the role of the arch code should be to provide primitive functions and
accessors with which to build the core code; pte_special does that. We do
not want architectures to know or care about vm_normal_page itself, and
we definitely don't want them being able to invent something new there
out of sight of mm/ code. If we made vm_normal_page an arch function, then
we have to make vm_insert_mixed (next patch) an arch function too. So I
don't think moving it to arch code fundamentally improves any abstractions,
while it does practically make the code more difficult to follow, for both
mm and arch developers, and easier to misuse.

[akpm@linux-foundation.org: build fix]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Carsten Otte <cotte@de.ibm.com>
Cc: Jared Hulbert <jaredeh@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28 08:58:23 -07:00

509 lines
18 KiB
C

#ifndef _PARISC_PGTABLE_H
#define _PARISC_PGTABLE_H
#include <asm-generic/4level-fixup.h>
#include <asm/fixmap.h>
#ifndef __ASSEMBLY__
/*
* we simulate an x86-style page table for the linux mm code
*/
#include <linux/mm.h> /* for vm_area_struct */
#include <linux/bitops.h>
#include <asm/processor.h>
#include <asm/cache.h>
/*
* kern_addr_valid(ADDR) tests if ADDR is pointing to valid kernel
* memory. For the return value to be meaningful, ADDR must be >=
* PAGE_OFFSET. This operation can be relatively expensive (e.g.,
* require a hash-, or multi-level tree-lookup or something of that
* sort) but it guarantees to return TRUE only if accessing the page
* at that address does not cause an error. Note that there may be
* addresses for which kern_addr_valid() returns FALSE even though an
* access would not cause an error (e.g., this is typically true for
* memory mapped I/O regions.
*
* XXX Need to implement this for parisc.
*/
#define kern_addr_valid(addr) (1)
/* Certain architectures need to do special things when PTEs
* within a page table are directly modified. Thus, the following
* hook is made available.
*/
#define set_pte(pteptr, pteval) \
do{ \
*(pteptr) = (pteval); \
} while(0)
#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
#endif /* !__ASSEMBLY__ */
#define pte_ERROR(e) \
printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
#define pmd_ERROR(e) \
printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, (unsigned long)pmd_val(e))
#define pgd_ERROR(e) \
printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, (unsigned long)pgd_val(e))
/* This is the size of the initially mapped kernel memory */
#ifdef CONFIG_64BIT
#define KERNEL_INITIAL_ORDER 24 /* 0 to 1<<24 = 16MB */
#else
#define KERNEL_INITIAL_ORDER 23 /* 0 to 1<<23 = 8MB */
#endif
#define KERNEL_INITIAL_SIZE (1 << KERNEL_INITIAL_ORDER)
#if defined(CONFIG_64BIT) && defined(CONFIG_PARISC_PAGE_SIZE_4KB)
#define PT_NLEVELS 3
#define PGD_ORDER 1 /* Number of pages per pgd */
#define PMD_ORDER 1 /* Number of pages per pmd */
#define PGD_ALLOC_ORDER 2 /* first pgd contains pmd */
#else
#define PT_NLEVELS 2
#define PGD_ORDER 1 /* Number of pages per pgd */
#define PGD_ALLOC_ORDER PGD_ORDER
#endif
/* Definitions for 3rd level (we use PLD here for Page Lower directory
* because PTE_SHIFT is used lower down to mean shift that has to be
* done to get usable bits out of the PTE) */
#define PLD_SHIFT PAGE_SHIFT
#define PLD_SIZE PAGE_SIZE
#define BITS_PER_PTE (PAGE_SHIFT - BITS_PER_PTE_ENTRY)
#define PTRS_PER_PTE (1UL << BITS_PER_PTE)
/* Definitions for 2nd level */
#define pgtable_cache_init() do { } while (0)
#define PMD_SHIFT (PLD_SHIFT + BITS_PER_PTE)
#define PMD_SIZE (1UL << PMD_SHIFT)
#define PMD_MASK (~(PMD_SIZE-1))
#if PT_NLEVELS == 3
#define BITS_PER_PMD (PAGE_SHIFT + PMD_ORDER - BITS_PER_PMD_ENTRY)
#else
#define BITS_PER_PMD 0
#endif
#define PTRS_PER_PMD (1UL << BITS_PER_PMD)
/* Definitions for 1st level */
#define PGDIR_SHIFT (PMD_SHIFT + BITS_PER_PMD)
#define BITS_PER_PGD (PAGE_SHIFT + PGD_ORDER - BITS_PER_PGD_ENTRY)
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
#define PGDIR_MASK (~(PGDIR_SIZE-1))
#define PTRS_PER_PGD (1UL << BITS_PER_PGD)
#define USER_PTRS_PER_PGD PTRS_PER_PGD
#define MAX_ADDRBITS (PGDIR_SHIFT + BITS_PER_PGD)
#define MAX_ADDRESS (1UL << MAX_ADDRBITS)
#define SPACEID_SHIFT (MAX_ADDRBITS - 32)
/* This calculates the number of initial pages we need for the initial
* page tables */
#if (KERNEL_INITIAL_ORDER) >= (PMD_SHIFT)
# define PT_INITIAL (1 << (KERNEL_INITIAL_ORDER - PMD_SHIFT))
#else
# define PT_INITIAL (1) /* all initial PTEs fit into one page */
#endif
/*
* pgd entries used up by user/kernel:
*/
#define FIRST_USER_ADDRESS 0
/* NB: The tlb miss handlers make certain assumptions about the order */
/* of the following bits, so be careful (One example, bits 25-31 */
/* are moved together in one instruction). */
#define _PAGE_READ_BIT 31 /* (0x001) read access allowed */
#define _PAGE_WRITE_BIT 30 /* (0x002) write access allowed */
#define _PAGE_EXEC_BIT 29 /* (0x004) execute access allowed */
#define _PAGE_GATEWAY_BIT 28 /* (0x008) privilege promotion allowed */
#define _PAGE_DMB_BIT 27 /* (0x010) Data Memory Break enable (B bit) */
#define _PAGE_DIRTY_BIT 26 /* (0x020) Page Dirty (D bit) */
#define _PAGE_FILE_BIT _PAGE_DIRTY_BIT /* overload this bit */
#define _PAGE_REFTRAP_BIT 25 /* (0x040) Page Ref. Trap enable (T bit) */
#define _PAGE_NO_CACHE_BIT 24 /* (0x080) Uncached Page (U bit) */
#define _PAGE_ACCESSED_BIT 23 /* (0x100) Software: Page Accessed */
#define _PAGE_PRESENT_BIT 22 /* (0x200) Software: translation valid */
#define _PAGE_FLUSH_BIT 21 /* (0x400) Software: translation valid */
/* for cache flushing only */
#define _PAGE_USER_BIT 20 /* (0x800) Software: User accessible page */
/* N.B. The bits are defined in terms of a 32 bit word above, so the */
/* following macro is ok for both 32 and 64 bit. */
#define xlate_pabit(x) (31 - x)
/* this defines the shift to the usable bits in the PTE it is set so
* that the valid bits _PAGE_PRESENT_BIT and _PAGE_USER_BIT are set
* to zero */
#define PTE_SHIFT xlate_pabit(_PAGE_USER_BIT)
/* PFN_PTE_SHIFT defines the shift of a PTE value to access the PFN field */
#define PFN_PTE_SHIFT 12
/* this is how many bits may be used by the file functions */
#define PTE_FILE_MAX_BITS (BITS_PER_LONG - PTE_SHIFT)
#define pte_to_pgoff(pte) (pte_val(pte) >> PTE_SHIFT)
#define pgoff_to_pte(off) ((pte_t) { ((off) << PTE_SHIFT) | _PAGE_FILE })
#define _PAGE_READ (1 << xlate_pabit(_PAGE_READ_BIT))
#define _PAGE_WRITE (1 << xlate_pabit(_PAGE_WRITE_BIT))
#define _PAGE_RW (_PAGE_READ | _PAGE_WRITE)
#define _PAGE_EXEC (1 << xlate_pabit(_PAGE_EXEC_BIT))
#define _PAGE_GATEWAY (1 << xlate_pabit(_PAGE_GATEWAY_BIT))
#define _PAGE_DMB (1 << xlate_pabit(_PAGE_DMB_BIT))
#define _PAGE_DIRTY (1 << xlate_pabit(_PAGE_DIRTY_BIT))
#define _PAGE_REFTRAP (1 << xlate_pabit(_PAGE_REFTRAP_BIT))
#define _PAGE_NO_CACHE (1 << xlate_pabit(_PAGE_NO_CACHE_BIT))
#define _PAGE_ACCESSED (1 << xlate_pabit(_PAGE_ACCESSED_BIT))
#define _PAGE_PRESENT (1 << xlate_pabit(_PAGE_PRESENT_BIT))
#define _PAGE_FLUSH (1 << xlate_pabit(_PAGE_FLUSH_BIT))
#define _PAGE_USER (1 << xlate_pabit(_PAGE_USER_BIT))
#define _PAGE_FILE (1 << xlate_pabit(_PAGE_FILE_BIT))
#define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)
#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
#define _PAGE_KERNEL (_PAGE_PRESENT | _PAGE_EXEC | _PAGE_READ | _PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)
/* The pgd/pmd contains a ptr (in phys addr space); since all pgds/pmds
* are page-aligned, we don't care about the PAGE_OFFSET bits, except
* for a few meta-information bits, so we shift the address to be
* able to effectively address 40/42/44-bits of physical address space
* depending on 4k/16k/64k PAGE_SIZE */
#define _PxD_PRESENT_BIT 31
#define _PxD_ATTACHED_BIT 30
#define _PxD_VALID_BIT 29
#define PxD_FLAG_PRESENT (1 << xlate_pabit(_PxD_PRESENT_BIT))
#define PxD_FLAG_ATTACHED (1 << xlate_pabit(_PxD_ATTACHED_BIT))
#define PxD_FLAG_VALID (1 << xlate_pabit(_PxD_VALID_BIT))
#define PxD_FLAG_MASK (0xf)
#define PxD_FLAG_SHIFT (4)
#define PxD_VALUE_SHIFT (8) /* (PAGE_SHIFT-PxD_FLAG_SHIFT) */
#ifndef __ASSEMBLY__
#define PAGE_NONE __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_ACCESSED)
/* Others seem to make this executable, I don't know if that's correct
or not. The stack is mapped this way though so this is necessary
in the short term - dhd@linuxcare.com, 2000-08-08 */
#define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_ACCESSED)
#define PAGE_WRITEONLY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_WRITE | _PAGE_ACCESSED)
#define PAGE_EXECREAD __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_EXEC |_PAGE_ACCESSED)
#define PAGE_COPY PAGE_EXECREAD
#define PAGE_RWX __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_READ | _PAGE_WRITE | _PAGE_EXEC |_PAGE_ACCESSED)
#define PAGE_KERNEL __pgprot(_PAGE_KERNEL)
#define PAGE_KERNEL_RO __pgprot(_PAGE_KERNEL & ~_PAGE_WRITE)
#define PAGE_KERNEL_UNC __pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
#define PAGE_GATEWAY __pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED | _PAGE_GATEWAY| _PAGE_READ)
#define PAGE_FLUSH __pgprot(_PAGE_FLUSH)
/*
* We could have an execute only page using "gateway - promote to priv
* level 3", but that is kind of silly. So, the way things are defined
* now, we must always have read permission for pages with execute
* permission. For the fun of it we'll go ahead and support write only
* pages.
*/
/*xwr*/
#define __P000 PAGE_NONE
#define __P001 PAGE_READONLY
#define __P010 __P000 /* copy on write */
#define __P011 __P001 /* copy on write */
#define __P100 PAGE_EXECREAD
#define __P101 PAGE_EXECREAD
#define __P110 __P100 /* copy on write */
#define __P111 __P101 /* copy on write */
#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
extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */
/* initial page tables for 0-8MB for kernel */
extern pte_t pg0[];
/* zero page used for uninitialized stuff */
extern unsigned long *empty_zero_page;
/*
* ZERO_PAGE is a global shared page that is always zero: used
* for zero-mapped memory areas etc..
*/
#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
#define pte_none(x) ((pte_val(x) == 0) || (pte_val(x) & _PAGE_FLUSH))
#define pte_present(x) (pte_val(x) & _PAGE_PRESENT)
#define pte_clear(mm,addr,xp) do { pte_val(*(xp)) = 0; } while (0)
#define pmd_flag(x) (pmd_val(x) & PxD_FLAG_MASK)
#define pmd_address(x) ((unsigned long)(pmd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
#define pgd_flag(x) (pgd_val(x) & PxD_FLAG_MASK)
#define pgd_address(x) ((unsigned long)(pgd_val(x) &~ PxD_FLAG_MASK) << PxD_VALUE_SHIFT)
#if PT_NLEVELS == 3
/* The first entry of the permanent pmd is not there if it contains
* the gateway marker */
#define pmd_none(x) (!pmd_val(x) || pmd_flag(x) == PxD_FLAG_ATTACHED)
#else
#define pmd_none(x) (!pmd_val(x))
#endif
#define pmd_bad(x) (!(pmd_flag(x) & PxD_FLAG_VALID))
#define pmd_present(x) (pmd_flag(x) & PxD_FLAG_PRESENT)
static inline void pmd_clear(pmd_t *pmd) {
#if PT_NLEVELS == 3
if (pmd_flag(*pmd) & PxD_FLAG_ATTACHED)
/* This is the entry pointing to the permanent pmd
* attached to the pgd; cannot clear it */
__pmd_val_set(*pmd, PxD_FLAG_ATTACHED);
else
#endif
__pmd_val_set(*pmd, 0);
}
#if PT_NLEVELS == 3
#define pgd_page_vaddr(pgd) ((unsigned long) __va(pgd_address(pgd)))
#define pgd_page(pgd) virt_to_page((void *)pgd_page_vaddr(pgd))
/* For 64 bit we have three level tables */
#define pgd_none(x) (!pgd_val(x))
#define pgd_bad(x) (!(pgd_flag(x) & PxD_FLAG_VALID))
#define pgd_present(x) (pgd_flag(x) & PxD_FLAG_PRESENT)
static inline void pgd_clear(pgd_t *pgd) {
#if PT_NLEVELS == 3
if(pgd_flag(*pgd) & PxD_FLAG_ATTACHED)
/* This is the permanent pmd attached to the pgd; cannot
* free it */
return;
#endif
__pgd_val_set(*pgd, 0);
}
#else
/*
* The "pgd_xxx()" functions here are trivial for a folded two-level
* setup: the pgd is never bad, and a pmd always exists (as it's folded
* into the pgd entry)
*/
static inline int pgd_none(pgd_t pgd) { return 0; }
static inline int pgd_bad(pgd_t pgd) { return 0; }
static inline int pgd_present(pgd_t pgd) { return 1; }
static inline void pgd_clear(pgd_t * pgdp) { }
#endif
/*
* The following only work if pte_present() is true.
* Undefined behaviour if not..
*/
static inline int pte_dirty(pte_t pte) { return pte_val(pte) & _PAGE_DIRTY; }
static inline int pte_young(pte_t pte) { return pte_val(pte) & _PAGE_ACCESSED; }
static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_WRITE; }
static inline int pte_file(pte_t pte) { return pte_val(pte) & _PAGE_FILE; }
static inline int pte_special(pte_t pte) { return 0; }
static inline pte_t pte_mkclean(pte_t pte) { pte_val(pte) &= ~_PAGE_DIRTY; return pte; }
static inline pte_t pte_mkold(pte_t pte) { pte_val(pte) &= ~_PAGE_ACCESSED; return pte; }
static inline pte_t pte_wrprotect(pte_t pte) { pte_val(pte) &= ~_PAGE_WRITE; return pte; }
static inline pte_t pte_mkdirty(pte_t pte) { pte_val(pte) |= _PAGE_DIRTY; return pte; }
static inline pte_t pte_mkyoung(pte_t pte) { pte_val(pte) |= _PAGE_ACCESSED; return pte; }
static inline pte_t pte_mkwrite(pte_t pte) { pte_val(pte) |= _PAGE_WRITE; return pte; }
static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
/*
* 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(addr,pgprot) \
({ \
pte_t __pte; \
\
pte_val(__pte) = ((((addr)>>PAGE_SHIFT)<<PFN_PTE_SHIFT) + pgprot_val(pgprot)); \
\
__pte; \
})
#define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
static inline pte_t pfn_pte(unsigned long pfn, pgprot_t pgprot)
{
pte_t pte;
pte_val(pte) = (pfn << PFN_PTE_SHIFT) | pgprot_val(pgprot);
return pte;
}
static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
{ pte_val(pte) = (pte_val(pte) & _PAGE_CHG_MASK) | pgprot_val(newprot); return pte; }
/* Permanent address of a page. On parisc we don't have highmem. */
#define pte_pfn(x) (pte_val(x) >> PFN_PTE_SHIFT)
#define pte_page(pte) (pfn_to_page(pte_pfn(pte)))
#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_address(pmd)))
#define __pmd_page(pmd) ((unsigned long) __va(pmd_address(pmd)))
#define pmd_page(pmd) virt_to_page((void *)__pmd_page(pmd))
#define pgd_index(address) ((address) >> PGDIR_SHIFT)
/* to find an entry in a page-table-directory */
#define pgd_offset(mm, address) \
((mm)->pgd + ((address) >> PGDIR_SHIFT))
/* 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 second-level page table.. */
#if PT_NLEVELS == 3
#define pmd_offset(dir,address) \
((pmd_t *) pgd_page_vaddr(*(dir)) + (((address)>>PMD_SHIFT) & (PTRS_PER_PMD-1)))
#else
#define pmd_offset(dir,addr) ((pmd_t *) dir)
#endif
/* Find an entry in the third-level page table.. */
#define pte_index(address) (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE-1))
#define pte_offset_kernel(pmd, address) \
((pte_t *) pmd_page_vaddr(*(pmd)) + pte_index(address))
#define pte_offset_map(pmd, address) pte_offset_kernel(pmd, address)
#define pte_offset_map_nested(pmd, address) pte_offset_kernel(pmd, address)
#define pte_unmap(pte) do { } while (0)
#define pte_unmap_nested(pte) do { } while (0)
#define pte_unmap(pte) do { } while (0)
#define pte_unmap_nested(pte) do { } while (0)
extern void paging_init (void);
/* Used for deferring calls to flush_dcache_page() */
#define PG_dcache_dirty PG_arch_1
extern void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t);
/* Encode and de-code a swap entry */
#define __swp_type(x) ((x).val & 0x1f)
#define __swp_offset(x) ( (((x).val >> 6) & 0x7) | \
(((x).val >> 8) & ~0x7) )
#define __swp_entry(type, offset) ((swp_entry_t) { (type) | \
((offset & 0x7) << 6) | \
((offset & ~0x7) << 8) })
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
static inline int ptep_test_and_clear_young(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)
{
#ifdef CONFIG_SMP
if (!pte_young(*ptep))
return 0;
return test_and_clear_bit(xlate_pabit(_PAGE_ACCESSED_BIT), &pte_val(*ptep));
#else
pte_t pte = *ptep;
if (!pte_young(pte))
return 0;
set_pte_at(vma->vm_mm, addr, ptep, pte_mkold(pte));
return 1;
#endif
}
extern spinlock_t pa_dbit_lock;
struct mm_struct;
static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
pte_t old_pte;
pte_t pte;
spin_lock(&pa_dbit_lock);
pte = old_pte = *ptep;
pte_val(pte) &= ~_PAGE_PRESENT;
pte_val(pte) |= _PAGE_FLUSH;
set_pte_at(mm,addr,ptep,pte);
spin_unlock(&pa_dbit_lock);
return old_pte;
}
static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
#ifdef CONFIG_SMP
unsigned long new, old;
do {
old = pte_val(*ptep);
new = pte_val(pte_wrprotect(__pte (old)));
} while (cmpxchg((unsigned long *) ptep, old, new) != old);
#else
pte_t old_pte = *ptep;
set_pte_at(mm, addr, ptep, pte_wrprotect(old_pte));
#endif
}
#define pte_same(A,B) (pte_val(A) == pte_val(B))
#endif /* !__ASSEMBLY__ */
/* TLB page size encoding - see table 3-1 in parisc20.pdf */
#define _PAGE_SIZE_ENCODING_4K 0
#define _PAGE_SIZE_ENCODING_16K 1
#define _PAGE_SIZE_ENCODING_64K 2
#define _PAGE_SIZE_ENCODING_256K 3
#define _PAGE_SIZE_ENCODING_1M 4
#define _PAGE_SIZE_ENCODING_4M 5
#define _PAGE_SIZE_ENCODING_16M 6
#define _PAGE_SIZE_ENCODING_64M 7
#if defined(CONFIG_PARISC_PAGE_SIZE_4KB)
# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_4K
#elif defined(CONFIG_PARISC_PAGE_SIZE_16KB)
# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_16K
#elif defined(CONFIG_PARISC_PAGE_SIZE_64KB)
# define _PAGE_SIZE_ENCODING_DEFAULT _PAGE_SIZE_ENCODING_64K
#endif
#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
remap_pfn_range(vma, vaddr, pfn, size, prot)
#define pgprot_noncached(prot) __pgprot(pgprot_val(prot) | _PAGE_NO_CACHE)
/* We provide our own get_unmapped_area to provide cache coherency */
#define HAVE_ARCH_UNMAPPED_AREA
#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
#define __HAVE_ARCH_PTEP_SET_WRPROTECT
#define __HAVE_ARCH_PTE_SAME
#include <asm-generic/pgtable.h>
#endif /* _PARISC_PGTABLE_H */