kernel-ark/include/asm-ppc64/pgtable.h
David Gibson e28f7faf05 [PATCH] Four level pagetables for ppc64
Implement 4-level pagetables for ppc64

This patch implements full four-level page tables for ppc64, thereby
extending the usable user address range to 44 bits (16T).

The patch uses a full page for the tables at the bottom and top level,
and a quarter page for the intermediate levels.  It uses full 64-bit
pointers at every level, thus also increasing the addressable range of
physical memory.  This patch also tweaks the VSID allocation to allow
matching range for user addresses (this halves the number of available
contexts) and adds some #if and BUILD_BUG sanity checks.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-08-29 10:53:31 +10:00

562 lines
18 KiB
C

#ifndef _PPC64_PGTABLE_H
#define _PPC64_PGTABLE_H
/*
* This file contains the functions and defines necessary to modify and use
* the ppc64 hashed page table.
*/
#ifndef __ASSEMBLY__
#include <linux/config.h>
#include <linux/stddef.h>
#include <asm/processor.h> /* For TASK_SIZE */
#include <asm/mmu.h>
#include <asm/page.h>
#include <asm/tlbflush.h>
#endif /* __ASSEMBLY__ */
/*
* Entries per page directory level. The PTE level must use a 64b record
* for each page table entry. The PMD and PGD level use a 32b record for
* each entry by assuming that each entry is page aligned.
*/
#define PTE_INDEX_SIZE 9
#define PMD_INDEX_SIZE 7
#define PUD_INDEX_SIZE 7
#define PGD_INDEX_SIZE 9
#define PTE_TABLE_SIZE (sizeof(pte_t) << PTE_INDEX_SIZE)
#define PMD_TABLE_SIZE (sizeof(pmd_t) << PMD_INDEX_SIZE)
#define PUD_TABLE_SIZE (sizeof(pud_t) << PUD_INDEX_SIZE)
#define PGD_TABLE_SIZE (sizeof(pgd_t) << PGD_INDEX_SIZE)
#define PTRS_PER_PTE (1 << PTE_INDEX_SIZE)
#define PTRS_PER_PMD (1 << PMD_INDEX_SIZE)
#define PTRS_PER_PUD (1 << PMD_INDEX_SIZE)
#define PTRS_PER_PGD (1 << PGD_INDEX_SIZE)
/* PMD_SHIFT determines what a second-level page table entry can map */
#define PMD_SHIFT (PAGE_SHIFT + PTE_INDEX_SIZE)
#define PMD_SIZE (1UL << PMD_SHIFT)
#define PMD_MASK (~(PMD_SIZE-1))
/* PUD_SHIFT determines what a third-level page table entry can map */
#define PUD_SHIFT (PMD_SHIFT + PMD_INDEX_SIZE)
#define PUD_SIZE (1UL << PUD_SHIFT)
#define PUD_MASK (~(PUD_SIZE-1))
/* PGDIR_SHIFT determines what a fourth-level page table entry can map */
#define PGDIR_SHIFT (PUD_SHIFT + PUD_INDEX_SIZE)
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
#define PGDIR_MASK (~(PGDIR_SIZE-1))
#define FIRST_USER_ADDRESS 0
/*
* Size of EA range mapped by our pagetables.
*/
#define PGTABLE_EADDR_SIZE (PTE_INDEX_SIZE + PMD_INDEX_SIZE + \
PUD_INDEX_SIZE + PGD_INDEX_SIZE + PAGE_SHIFT)
#define PGTABLE_RANGE (1UL << PGTABLE_EADDR_SIZE)
#if TASK_SIZE_USER64 > PGTABLE_RANGE
#error TASK_SIZE_USER64 exceeds pagetable range
#endif
#if TASK_SIZE_USER64 > (1UL << (USER_ESID_BITS + SID_SHIFT))
#error TASK_SIZE_USER64 exceeds user VSID range
#endif
/*
* Define the address range of the vmalloc VM area.
*/
#define VMALLOC_START (0xD000000000000000ul)
#define VMALLOC_SIZE (0x80000000000UL)
#define VMALLOC_END (VMALLOC_START + VMALLOC_SIZE)
/*
* Bits in a linux-style PTE. These match the bits in the
* (hardware-defined) PowerPC PTE as closely as possible.
*/
#define _PAGE_PRESENT 0x0001 /* software: pte contains a translation */
#define _PAGE_USER 0x0002 /* matches one of the PP bits */
#define _PAGE_FILE 0x0002 /* (!present only) software: pte holds file offset */
#define _PAGE_EXEC 0x0004 /* No execute on POWER4 and newer (we invert) */
#define _PAGE_GUARDED 0x0008
#define _PAGE_COHERENT 0x0010 /* M: enforce memory coherence (SMP systems) */
#define _PAGE_NO_CACHE 0x0020 /* I: cache inhibit */
#define _PAGE_WRITETHRU 0x0040 /* W: cache write-through */
#define _PAGE_DIRTY 0x0080 /* C: page changed */
#define _PAGE_ACCESSED 0x0100 /* R: page referenced */
#define _PAGE_RW 0x0200 /* software: user write access allowed */
#define _PAGE_HASHPTE 0x0400 /* software: pte has an associated HPTE */
#define _PAGE_BUSY 0x0800 /* software: PTE & hash are busy */
#define _PAGE_SECONDARY 0x8000 /* software: HPTE is in secondary group */
#define _PAGE_GROUP_IX 0x7000 /* software: HPTE index within group */
#define _PAGE_HUGE 0x10000 /* 16MB page */
/* Bits 0x7000 identify the index within an HPT Group */
#define _PAGE_HPTEFLAGS (_PAGE_BUSY | _PAGE_HASHPTE | _PAGE_SECONDARY | _PAGE_GROUP_IX)
/* PAGE_MASK gives the right answer below, but only by accident */
/* It should be preserving the high 48 bits and then specifically */
/* preserving _PAGE_SECONDARY | _PAGE_GROUP_IX */
#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY | _PAGE_HPTEFLAGS)
#define _PAGE_BASE (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_COHERENT)
#define _PAGE_WRENABLE (_PAGE_RW | _PAGE_DIRTY)
/* __pgprot defined in asm-ppc64/page.h */
#define PAGE_NONE __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED)
#define PAGE_SHARED __pgprot(_PAGE_BASE | _PAGE_RW | _PAGE_USER)
#define PAGE_SHARED_X __pgprot(_PAGE_BASE | _PAGE_RW | _PAGE_USER | _PAGE_EXEC)
#define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_USER)
#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_USER)
#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_USER | _PAGE_EXEC)
#define PAGE_KERNEL __pgprot(_PAGE_BASE | _PAGE_WRENABLE)
#define PAGE_KERNEL_CI __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | \
_PAGE_WRENABLE | _PAGE_NO_CACHE | _PAGE_GUARDED)
#define PAGE_KERNEL_EXEC __pgprot(_PAGE_BASE | _PAGE_WRENABLE | _PAGE_EXEC)
#define PAGE_AGP __pgprot(_PAGE_BASE | _PAGE_WRENABLE | _PAGE_NO_CACHE)
#define HAVE_PAGE_AGP
/*
* This bit in a hardware PTE indicates that the page is *not* executable.
*/
#define HW_NO_EXEC _PAGE_EXEC
/*
* POWER4 and newer have per page execute protection, older chips can only
* do this on a segment (256MB) basis.
*
* Also, write permissions imply read permissions.
* This is the closest we can get..
*
* Note due to the way vm flags are laid out, the bits are XWR
*/
#define __P000 PAGE_NONE
#define __P001 PAGE_READONLY
#define __P010 PAGE_COPY
#define __P011 PAGE_COPY
#define __P100 PAGE_READONLY_X
#define __P101 PAGE_READONLY_X
#define __P110 PAGE_COPY_X
#define __P111 PAGE_COPY_X
#define __S000 PAGE_NONE
#define __S001 PAGE_READONLY
#define __S010 PAGE_SHARED
#define __S011 PAGE_SHARED
#define __S100 PAGE_READONLY_X
#define __S101 PAGE_READONLY_X
#define __S110 PAGE_SHARED_X
#define __S111 PAGE_SHARED_X
#ifndef __ASSEMBLY__
/*
* 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__ */
/* shift to put page number into pte */
#define PTE_SHIFT (17)
#ifdef CONFIG_HUGETLB_PAGE
#ifndef __ASSEMBLY__
int hash_huge_page(struct mm_struct *mm, unsigned long access,
unsigned long ea, unsigned long vsid, int local);
#endif /* __ASSEMBLY__ */
#define HAVE_ARCH_UNMAPPED_AREA
#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
#else
#define hash_huge_page(mm,a,ea,vsid,local) -1
#endif
#ifndef __ASSEMBLY__
/*
* Conversion functions: convert a page and protection to a page entry,
* and a page entry and page directory to the page they refer to.
*
* mk_pte takes a (struct page *) as input
*/
#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 << PTE_SHIFT) | pgprot_val(pgprot);
return pte;
}
#define pte_modify(_pte, newprot) \
(__pte((pte_val(_pte) & _PAGE_CHG_MASK) | pgprot_val(newprot)))
#define pte_none(pte) ((pte_val(pte) & ~_PAGE_HPTEFLAGS) == 0)
#define pte_present(pte) (pte_val(pte) & _PAGE_PRESENT)
/* pte_clear moved to later in this file */
#define pte_pfn(x) ((unsigned long)((pte_val(x) >> PTE_SHIFT)))
#define pte_page(x) pfn_to_page(pte_pfn(x))
#define pmd_set(pmdp, ptep) ({BUG_ON((u64)ptep < KERNELBASE); pmd_val(*(pmdp)) = (unsigned long)(ptep);})
#define pmd_none(pmd) (!pmd_val(pmd))
#define pmd_bad(pmd) (pmd_val(pmd) == 0)
#define pmd_present(pmd) (pmd_val(pmd) != 0)
#define pmd_clear(pmdp) (pmd_val(*(pmdp)) = 0)
#define pmd_page_kernel(pmd) (pmd_val(pmd))
#define pmd_page(pmd) virt_to_page(pmd_page_kernel(pmd))
#define pud_set(pudp, pmdp) (pud_val(*(pudp)) = (unsigned long)(pmdp))
#define pud_none(pud) (!pud_val(pud))
#define pud_bad(pud) ((pud_val(pud)) == 0)
#define pud_present(pud) (pud_val(pud) != 0)
#define pud_clear(pudp) (pud_val(*(pudp)) = 0)
#define pud_page(pud) (pud_val(pud))
#define pgd_set(pgdp, pudp) ({pgd_val(*(pgdp)) = (unsigned long)(pudp);})
#define pgd_none(pgd) (!pgd_val(pgd))
#define pgd_bad(pgd) (pgd_val(pgd) == 0)
#define pgd_present(pgd) (pgd_val(pgd) != 0)
#define pgd_clear(pgdp) (pgd_val(*(pgdp)) = 0)
#define pgd_page(pgd) (pgd_val(pgd))
/*
* Find an entry in a page-table-directory. We combine the address region
* (the high order N bits) and the pgd portion of the address.
*/
/* to avoid overflow in free_pgtables we don't use PTRS_PER_PGD here */
#define pgd_index(address) (((address) >> (PGDIR_SHIFT)) & 0x1ff)
#define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
#define pud_offset(pgdp, addr) \
(((pud_t *) pgd_page(*(pgdp))) + (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1)))
#define pmd_offset(pudp,addr) \
(((pmd_t *) pud_page(*(pudp))) + (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)))
#define pte_offset_kernel(dir,addr) \
(((pte_t *) pmd_page_kernel(*(dir))) + (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)))
#define pte_offset_map(dir,addr) pte_offset_kernel((dir), (addr))
#define pte_offset_map_nested(dir,addr) pte_offset_kernel((dir), (addr))
#define pte_unmap(pte) do { } while(0)
#define pte_unmap_nested(pte) do { } while(0)
/* to find an entry in a kernel page-table-directory */
/* This now only contains the vmalloc pages */
#define pgd_offset_k(address) pgd_offset(&init_mm, address)
/*
* The following only work if pte_present() is true.
* Undefined behaviour if not..
*/
static inline int pte_read(pte_t pte) { return pte_val(pte) & _PAGE_USER;}
static inline int pte_write(pte_t pte) { return pte_val(pte) & _PAGE_RW;}
static inline int pte_exec(pte_t pte) { return pte_val(pte) & _PAGE_EXEC;}
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_file(pte_t pte) { return pte_val(pte) & _PAGE_FILE;}
static inline int pte_huge(pte_t pte) { return pte_val(pte) & _PAGE_HUGE;}
static inline void pte_uncache(pte_t pte) { pte_val(pte) |= _PAGE_NO_CACHE; }
static inline void pte_cache(pte_t pte) { pte_val(pte) &= ~_PAGE_NO_CACHE; }
static inline pte_t pte_rdprotect(pte_t pte) {
pte_val(pte) &= ~_PAGE_USER; return pte; }
static inline pte_t pte_exprotect(pte_t pte) {
pte_val(pte) &= ~_PAGE_EXEC; return pte; }
static inline pte_t pte_wrprotect(pte_t pte) {
pte_val(pte) &= ~(_PAGE_RW); return pte; }
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_mkread(pte_t pte) {
pte_val(pte) |= _PAGE_USER; return pte; }
static inline pte_t pte_mkexec(pte_t pte) {
pte_val(pte) |= _PAGE_USER | _PAGE_EXEC; return pte; }
static inline pte_t pte_mkwrite(pte_t pte) {
pte_val(pte) |= _PAGE_RW; 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_mkhuge(pte_t pte) {
pte_val(pte) |= _PAGE_HUGE; return pte; }
/* Atomic PTE updates */
static inline unsigned long pte_update(pte_t *p, unsigned long clr)
{
unsigned long old, tmp;
__asm__ __volatile__(
"1: ldarx %0,0,%3 # pte_update\n\
andi. %1,%0,%6\n\
bne- 1b \n\
andc %1,%0,%4 \n\
stdcx. %1,0,%3 \n\
bne- 1b"
: "=&r" (old), "=&r" (tmp), "=m" (*p)
: "r" (p), "r" (clr), "m" (*p), "i" (_PAGE_BUSY)
: "cc" );
return old;
}
/* PTE updating functions, this function puts the PTE in the
* batch, doesn't actually triggers the hash flush immediately,
* you need to call flush_tlb_pending() to do that.
*/
extern void hpte_update(struct mm_struct *mm, unsigned long addr, unsigned long pte,
int wrprot);
static inline int __ptep_test_and_clear_young(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
unsigned long old;
if ((pte_val(*ptep) & (_PAGE_ACCESSED | _PAGE_HASHPTE)) == 0)
return 0;
old = pte_update(ptep, _PAGE_ACCESSED);
if (old & _PAGE_HASHPTE) {
hpte_update(mm, addr, old, 0);
flush_tlb_pending();
}
return (old & _PAGE_ACCESSED) != 0;
}
#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
#define ptep_test_and_clear_young(__vma, __addr, __ptep) \
({ \
int __r; \
__r = __ptep_test_and_clear_young((__vma)->vm_mm, __addr, __ptep); \
__r; \
})
/*
* On RW/DIRTY bit transitions we can avoid flushing the hpte. For the
* moment we always flush but we need to fix hpte_update and test if the
* optimisation is worth it.
*/
static inline int __ptep_test_and_clear_dirty(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
unsigned long old;
if ((pte_val(*ptep) & _PAGE_DIRTY) == 0)
return 0;
old = pte_update(ptep, _PAGE_DIRTY);
if (old & _PAGE_HASHPTE)
hpte_update(mm, addr, old, 0);
return (old & _PAGE_DIRTY) != 0;
}
#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_DIRTY
#define ptep_test_and_clear_dirty(__vma, __addr, __ptep) \
({ \
int __r; \
__r = __ptep_test_and_clear_dirty((__vma)->vm_mm, __addr, __ptep); \
__r; \
})
#define __HAVE_ARCH_PTEP_SET_WRPROTECT
static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
unsigned long old;
if ((pte_val(*ptep) & _PAGE_RW) == 0)
return;
old = pte_update(ptep, _PAGE_RW);
if (old & _PAGE_HASHPTE)
hpte_update(mm, addr, old, 0);
}
/*
* We currently remove entries from the hashtable regardless of whether
* the entry was young or dirty. The generic routines only flush if the
* entry was young or dirty which is not good enough.
*
* We should be more intelligent about this but for the moment we override
* these functions and force a tlb flush unconditionally
*/
#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
#define ptep_clear_flush_young(__vma, __address, __ptep) \
({ \
int __young = __ptep_test_and_clear_young((__vma)->vm_mm, __address, \
__ptep); \
__young; \
})
#define __HAVE_ARCH_PTEP_CLEAR_DIRTY_FLUSH
#define ptep_clear_flush_dirty(__vma, __address, __ptep) \
({ \
int __dirty = __ptep_test_and_clear_dirty((__vma)->vm_mm, __address, \
__ptep); \
flush_tlb_page(__vma, __address); \
__dirty; \
})
#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
unsigned long old = pte_update(ptep, ~0UL);
if (old & _PAGE_HASHPTE)
hpte_update(mm, addr, old, 0);
return __pte(old);
}
static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t * ptep)
{
unsigned long old = pte_update(ptep, ~0UL);
if (old & _PAGE_HASHPTE)
hpte_update(mm, addr, old, 0);
}
/*
* set_pte stores a linux PTE into the linux page table.
*/
static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pte)
{
if (pte_present(*ptep)) {
pte_clear(mm, addr, ptep);
flush_tlb_pending();
}
*ptep = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
}
/* Set the dirty and/or accessed bits atomically in a linux PTE, this
* function doesn't need to flush the hash entry
*/
#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry, int dirty)
{
unsigned long bits = pte_val(entry) &
(_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
unsigned long old, tmp;
__asm__ __volatile__(
"1: ldarx %0,0,%4\n\
andi. %1,%0,%6\n\
bne- 1b \n\
or %0,%3,%0\n\
stdcx. %0,0,%4\n\
bne- 1b"
:"=&r" (old), "=&r" (tmp), "=m" (*ptep)
:"r" (bits), "r" (ptep), "m" (*ptep), "i" (_PAGE_BUSY)
:"cc");
}
#define ptep_set_access_flags(__vma, __address, __ptep, __entry, __dirty) \
do { \
__ptep_set_access_flags(__ptep, __entry, __dirty); \
flush_tlb_page_nohash(__vma, __address); \
} while(0)
/*
* Macro to mark a page protection value as "uncacheable".
*/
#define pgprot_noncached(prot) (__pgprot(pgprot_val(prot) | _PAGE_NO_CACHE | _PAGE_GUARDED))
struct file;
extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long addr,
unsigned long size, pgprot_t vma_prot);
#define __HAVE_PHYS_MEM_ACCESS_PROT
#define __HAVE_ARCH_PTE_SAME
#define pte_same(A,B) (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HPTEFLAGS) == 0)
#define pmd_ERROR(e) \
printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, pmd_val(e))
#define pud_ERROR(e) \
printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, pud_val(e))
#define pgd_ERROR(e) \
printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
extern pgd_t swapper_pg_dir[];
extern void paging_init(void);
#define hugetlb_free_pgd_range(tlb, addr, end, floor, ceiling) \
free_pgd_range(tlb, addr, end, floor, ceiling)
/*
* This gets called at the end of handling a page fault, when
* the kernel has put a new PTE into the page table for the process.
* We use it to put a corresponding HPTE into the hash table
* ahead of time, instead of waiting for the inevitable extra
* hash-table miss exception.
*/
struct vm_area_struct;
extern void update_mmu_cache(struct vm_area_struct *, unsigned long, pte_t);
/* Encode and de-code a swap entry */
#define __swp_type(entry) (((entry).val >> 1) & 0x3f)
#define __swp_offset(entry) ((entry).val >> 8)
#define __swp_entry(type, offset) ((swp_entry_t) { ((type) << 1) | ((offset) << 8) })
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) >> PTE_SHIFT })
#define __swp_entry_to_pte(x) ((pte_t) { (x).val << 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 PTE_FILE_MAX_BITS (BITS_PER_LONG - PTE_SHIFT)
/*
* kern_addr_valid is intended to indicate whether an address is a valid
* kernel address. Most 32-bit archs define it as always true (like this)
* but most 64-bit archs actually perform a test. What should we do here?
* The only use is in fs/ncpfs/dir.c
*/
#define kern_addr_valid(addr) (1)
#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
remap_pfn_range(vma, vaddr, pfn, size, prot)
void pgtable_cache_init(void);
/*
* find_linux_pte returns the address of a linux pte for a given
* effective address and directory. If not found, it returns zero.
*/
static inline pte_t *find_linux_pte(pgd_t *pgdir, unsigned long ea)
{
pgd_t *pg;
pud_t *pu;
pmd_t *pm;
pte_t *pt = NULL;
pte_t pte;
pg = pgdir + pgd_index(ea);
if (!pgd_none(*pg)) {
pu = pud_offset(pg, ea);
if (!pud_none(*pu)) {
pm = pmd_offset(pu, ea);
if (pmd_present(*pm)) {
pt = pte_offset_kernel(pm, ea);
pte = *pt;
if (!pte_present(pte))
pt = NULL;
}
}
}
return pt;
}
#include <asm-generic/pgtable.h>
#endif /* __ASSEMBLY__ */
#endif /* _PPC64_PGTABLE_H */