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authorDavid Gibson <david@gibson.dropbear.id.au>2007-04-30 16:30:56 +1000
committerPaul Mackerras <paulus@samba.org>2007-05-02 20:04:30 +1000
commitf88df14b1f15cdeffa060580a40c1ce3e13bb79e (patch)
tree0619f32c2be79a85792537ad4410cc8d729f4f75 /include/asm-powerpc/pgtable-ppc64.h
parent69d48b409cac747cc0707b05b769e38488a6ad35 (diff)
[POWERPC] Remove arch/powerpc's dependence on asm-ppc/pg{alloc,table}.h
Currently, all 32-bit powerpc platforms use asm-ppc/pgtable.h and asm-ppc/pgalloc.h, even when otherwise compiled with ARCH=powerpc. Those asm-ppc files are a fairly nasty tangle of #ifdefs including a bunch of things which shouldn't be necessary any more in arch/powerpc. Cleaning up that mess is going to take a while, but this patch is a first step. It separates the asm-powerpc/pg{alloc,table}.h into 64 bit and 32 bit versions in asm-powerpc, which the basic .h files in asm-powerpc select based on config. We make a few tiny tweaks to the innards of the files along the way, making the outermost ifdefs (double-inclusion protection and __KERNEL__) a little cleaner, and #including asm-generic/pgtable.h from the top-level asm-powerpc/pgtable.h (since both the old 32-bit and 64-bit versions ended with such an #include). Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
Diffstat (limited to 'include/asm-powerpc/pgtable-ppc64.h')
-rw-r--r--include/asm-powerpc/pgtable-ppc64.h492
1 files changed, 492 insertions, 0 deletions
diff --git a/include/asm-powerpc/pgtable-ppc64.h b/include/asm-powerpc/pgtable-ppc64.h
new file mode 100644
index 00000000000..704c4e669fe
--- /dev/null
+++ b/include/asm-powerpc/pgtable-ppc64.h
@@ -0,0 +1,492 @@
+#ifndef _ASM_POWERPC_PGTABLE_PPC64_H_
+#define _ASM_POWERPC_PGTABLE_PPC64_H_
+/*
+ * This file contains the functions and defines necessary to modify and use
+ * the ppc64 hashed page table.
+ */
+
+#ifndef __ASSEMBLY__
+#include <linux/stddef.h>
+#include <asm/processor.h> /* For TASK_SIZE */
+#include <asm/mmu.h>
+#include <asm/page.h>
+#include <asm/tlbflush.h>
+struct mm_struct;
+#endif /* __ASSEMBLY__ */
+
+#ifdef CONFIG_PPC_64K_PAGES
+#include <asm/pgtable-64k.h>
+#else
+#include <asm/pgtable-4k.h>
+#endif
+
+#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 ASM_CONST(0xD000000000000000)
+#define VMALLOC_SIZE ASM_CONST(0x80000000000)
+#define VMALLOC_END (VMALLOC_START + VMALLOC_SIZE)
+
+/*
+ * Define the address range of the imalloc VM area.
+ */
+#define PHBS_IO_BASE VMALLOC_END
+#define IMALLOC_BASE (PHBS_IO_BASE + 0x80000000ul) /* Reserve 2 gigs for PHBs */
+#define IMALLOC_END (VMALLOC_START + PGTABLE_RANGE)
+
+/*
+ * Region IDs
+ */
+#define REGION_SHIFT 60UL
+#define REGION_MASK (0xfUL << REGION_SHIFT)
+#define REGION_ID(ea) (((unsigned long)(ea)) >> REGION_SHIFT)
+
+#define VMALLOC_REGION_ID (REGION_ID(VMALLOC_START))
+#define KERNEL_REGION_ID (REGION_ID(PAGE_OFFSET))
+#define USER_REGION_ID (0UL)
+
+/*
+ * Common bits in a linux-style PTE. These match the bits in the
+ * (hardware-defined) PowerPC PTE as closely as possible. Additional
+ * bits may be defined in pgtable-*.h
+ */
+#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_BASE (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_COHERENT)
+
+#define _PAGE_WRENABLE (_PAGE_RW | _PAGE_DIRTY)
+
+/* __pgprot defined in asm-powerpc/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
+
+/* PTEIDX nibble */
+#define _PTEIDX_SECONDARY 0x8
+#define _PTEIDX_GROUP_IX 0x7
+
+
+/*
+ * 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__ */
+
+#ifdef CONFIG_HUGETLB_PAGE
+
+#define HAVE_ARCH_UNMAPPED_AREA
+#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
+
+#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_RPN_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_RPN_SHIFT)))
+#define pte_page(x) pfn_to_page(pte_pfn(x))
+
+#define PMD_BAD_BITS (PTE_TABLE_SIZE-1)
+#define PUD_BAD_BITS (PMD_TABLE_SIZE-1)
+
+#define pmd_set(pmdp, pmdval) (pmd_val(*(pmdp)) = (pmdval))
+#define pmd_none(pmd) (!pmd_val(pmd))
+#define pmd_bad(pmd) (!is_kernel_addr(pmd_val(pmd)) \
+ || (pmd_val(pmd) & PMD_BAD_BITS))
+#define pmd_present(pmd) (pmd_val(pmd) != 0)
+#define pmd_clear(pmdp) (pmd_val(*(pmdp)) = 0)
+#define pmd_page_vaddr(pmd) (pmd_val(pmd) & ~PMD_MASKED_BITS)
+#define pmd_page(pmd) virt_to_page(pmd_page_vaddr(pmd))
+
+#define pud_set(pudp, pudval) (pud_val(*(pudp)) = (pudval))
+#define pud_none(pud) (!pud_val(pud))
+#define pud_bad(pud) (!is_kernel_addr(pud_val(pud)) \
+ || (pud_val(pud) & PUD_BAD_BITS))
+#define pud_present(pud) (pud_val(pud) != 0)
+#define pud_clear(pudp) (pud_val(*(pudp)) = 0)
+#define pud_page_vaddr(pud) (pud_val(pud) & ~PUD_MASKED_BITS)
+#define pud_page(pud) virt_to_page(pud_page_vaddr(pud))
+
+#define pgd_set(pgdp, pudp) ({pgd_val(*(pgdp)) = (unsigned long)(pudp);})
+
+/*
+ * 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 pmd_offset(pudp,addr) \
+ (((pmd_t *) pud_page_vaddr(*(pudp))) + (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)))
+
+#define pte_offset_kernel(dir,addr) \
+ (((pte_t *) pmd_page_vaddr(*(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 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) {
+ return pte; }
+
+/* Atomic PTE updates */
+static inline unsigned long pte_update(struct mm_struct *mm,
+ unsigned long addr,
+ pte_t *ptep, unsigned long clr,
+ int huge)
+{
+ 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" (*ptep)
+ : "r" (ptep), "r" (clr), "m" (*ptep), "i" (_PAGE_BUSY)
+ : "cc" );
+
+ if (old & _PAGE_HASHPTE)
+ hpte_need_flush(mm, addr, ptep, old, huge);
+ return old;
+}
+
+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(mm, addr, ptep, _PAGE_ACCESSED, 0);
+ 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(mm, addr, ptep, _PAGE_DIRTY, 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(mm, addr, ptep, _PAGE_RW, 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); \
+ __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(mm, addr, ptep, ~0UL, 0);
+ return __pte(old);
+}
+
+static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
+ pte_t * ptep)
+{
+ pte_update(mm, addr, ptep, ~0UL, 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);
+ pte = __pte(pte_val(pte) & ~_PAGE_HPTEFLAGS);
+ *ptep = pte;
+}
+
+/* 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 pfn,
+ 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 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__, pmd_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);
+
+/* 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_RPN_SHIFT})
+#define __swp_entry_to_pte(x) ((pte_t) { (x).val << PTE_RPN_SHIFT })
+#define pte_to_pgoff(pte) (pte_val(pte) >> PTE_RPN_SHIFT)
+#define pgoff_to_pte(off) ((pte_t) {((off) << PTE_RPN_SHIFT)|_PAGE_FILE})
+#define PTE_FILE_MAX_BITS (BITS_PER_LONG - PTE_RPN_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;
+
+ 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);
+ }
+ }
+ return pt;
+}
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* _ASM_POWERPC_PGTABLE_PPC64_H_ */