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-rw-r--r--arch/ia64/include/asm/pgtable.h597
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diff --git a/arch/ia64/include/asm/pgtable.h b/arch/ia64/include/asm/pgtable.h
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+++ b/arch/ia64/include/asm/pgtable.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_IA64_PGTABLE_H
+#define _ASM_IA64_PGTABLE_H
+
+/*
+ * This file contains the functions and defines necessary to modify and use
+ * the IA-64 page table tree.
+ *
+ * This hopefully works with any (fixed) IA-64 page-size, as defined
+ * in <asm/page.h>.
+ *
+ * Copyright (C) 1998-2005 Hewlett-Packard Co
+ * David Mosberger-Tang <davidm@hpl.hp.com>
+ */
+
+
+#include <asm/mman.h>
+#include <asm/page.h>
+#include <asm/processor.h>
+#include <asm/types.h>
+
+#define IA64_MAX_PHYS_BITS 50 /* max. number of physical address bits (architected) */
+
+/*
+ * First, define the various bits in a PTE. Note that the PTE format
+ * matches the VHPT short format, the firt doubleword of the VHPD long
+ * format, and the first doubleword of the TLB insertion format.
+ */
+#define _PAGE_P_BIT 0
+#define _PAGE_A_BIT 5
+#define _PAGE_D_BIT 6
+
+#define _PAGE_P (1 << _PAGE_P_BIT) /* page present bit */
+#define _PAGE_MA_WB (0x0 << 2) /* write back memory attribute */
+#define _PAGE_MA_UC (0x4 << 2) /* uncacheable memory attribute */
+#define _PAGE_MA_UCE (0x5 << 2) /* UC exported attribute */
+#define _PAGE_MA_WC (0x6 << 2) /* write coalescing memory attribute */
+#define _PAGE_MA_NAT (0x7 << 2) /* not-a-thing attribute */
+#define _PAGE_MA_MASK (0x7 << 2)
+#define _PAGE_PL_0 (0 << 7) /* privilege level 0 (kernel) */
+#define _PAGE_PL_1 (1 << 7) /* privilege level 1 (unused) */
+#define _PAGE_PL_2 (2 << 7) /* privilege level 2 (unused) */
+#define _PAGE_PL_3 (3 << 7) /* privilege level 3 (user) */
+#define _PAGE_PL_MASK (3 << 7)
+#define _PAGE_AR_R (0 << 9) /* read only */
+#define _PAGE_AR_RX (1 << 9) /* read & execute */
+#define _PAGE_AR_RW (2 << 9) /* read & write */
+#define _PAGE_AR_RWX (3 << 9) /* read, write & execute */
+#define _PAGE_AR_R_RW (4 << 9) /* read / read & write */
+#define _PAGE_AR_RX_RWX (5 << 9) /* read & exec / read, write & exec */
+#define _PAGE_AR_RWX_RW (6 << 9) /* read, write & exec / read & write */
+#define _PAGE_AR_X_RX (7 << 9) /* exec & promote / read & exec */
+#define _PAGE_AR_MASK (7 << 9)
+#define _PAGE_AR_SHIFT 9
+#define _PAGE_A (1 << _PAGE_A_BIT) /* page accessed bit */
+#define _PAGE_D (1 << _PAGE_D_BIT) /* page dirty bit */
+#define _PAGE_PPN_MASK (((__IA64_UL(1) << IA64_MAX_PHYS_BITS) - 1) & ~0xfffUL)
+#define _PAGE_ED (__IA64_UL(1) << 52) /* exception deferral */
+#define _PAGE_PROTNONE (__IA64_UL(1) << 63)
+
+#define _PFN_MASK _PAGE_PPN_MASK
+/* Mask of bits which may be changed by pte_modify(); the odd bits are there for _PAGE_PROTNONE */
+#define _PAGE_CHG_MASK (_PAGE_P | _PAGE_PROTNONE | _PAGE_PL_MASK | _PAGE_AR_MASK | _PAGE_ED)
+
+#define _PAGE_SIZE_4K 12
+#define _PAGE_SIZE_8K 13
+#define _PAGE_SIZE_16K 14
+#define _PAGE_SIZE_64K 16
+#define _PAGE_SIZE_256K 18
+#define _PAGE_SIZE_1M 20
+#define _PAGE_SIZE_4M 22
+#define _PAGE_SIZE_16M 24
+#define _PAGE_SIZE_64M 26
+#define _PAGE_SIZE_256M 28
+#define _PAGE_SIZE_1G 30
+#define _PAGE_SIZE_4G 32
+
+#define __ACCESS_BITS _PAGE_ED | _PAGE_A | _PAGE_P | _PAGE_MA_WB
+#define __DIRTY_BITS_NO_ED _PAGE_A | _PAGE_P | _PAGE_D | _PAGE_MA_WB
+#define __DIRTY_BITS _PAGE_ED | __DIRTY_BITS_NO_ED
+
+/*
+ * How many pointers will a page table level hold expressed in shift
+ */
+#define PTRS_PER_PTD_SHIFT (PAGE_SHIFT-3)
+
+/*
+ * Definitions for fourth level:
+ */
+#define PTRS_PER_PTE (__IA64_UL(1) << (PTRS_PER_PTD_SHIFT))
+
+/*
+ * Definitions for third level:
+ *
+ * PMD_SHIFT determines the size of the area a third-level page table
+ * can map.
+ */
+#define PMD_SHIFT (PAGE_SHIFT + (PTRS_PER_PTD_SHIFT))
+#define PMD_SIZE (1UL << PMD_SHIFT)
+#define PMD_MASK (~(PMD_SIZE-1))
+#define PTRS_PER_PMD (1UL << (PTRS_PER_PTD_SHIFT))
+
+#if CONFIG_PGTABLE_LEVELS == 4
+/*
+ * Definitions for second level:
+ *
+ * PUD_SHIFT determines the size of the area a second-level page table
+ * can map.
+ */
+#define PUD_SHIFT (PMD_SHIFT + (PTRS_PER_PTD_SHIFT))
+#define PUD_SIZE (1UL << PUD_SHIFT)
+#define PUD_MASK (~(PUD_SIZE-1))
+#define PTRS_PER_PUD (1UL << (PTRS_PER_PTD_SHIFT))
+#endif
+
+/*
+ * Definitions for first level:
+ *
+ * PGDIR_SHIFT determines what a first-level page table entry can map.
+ */
+#if CONFIG_PGTABLE_LEVELS == 4
+#define PGDIR_SHIFT (PUD_SHIFT + (PTRS_PER_PTD_SHIFT))
+#else
+#define PGDIR_SHIFT (PMD_SHIFT + (PTRS_PER_PTD_SHIFT))
+#endif
+#define PGDIR_SIZE (__IA64_UL(1) << PGDIR_SHIFT)
+#define PGDIR_MASK (~(PGDIR_SIZE-1))
+#define PTRS_PER_PGD_SHIFT PTRS_PER_PTD_SHIFT
+#define PTRS_PER_PGD (1UL << PTRS_PER_PGD_SHIFT)
+#define USER_PTRS_PER_PGD (5*PTRS_PER_PGD/8) /* regions 0-4 are user regions */
+#define FIRST_USER_ADDRESS 0UL
+
+/*
+ * All the normal masks have the "page accessed" bits on, as any time
+ * they are used, the page is accessed. They are cleared only by the
+ * page-out routines.
+ */
+#define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_A)
+#define PAGE_SHARED __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RW)
+#define PAGE_READONLY __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_R)
+#define PAGE_COPY __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_R)
+#define PAGE_COPY_EXEC __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX)
+#define PAGE_GATE __pgprot(__ACCESS_BITS | _PAGE_PL_0 | _PAGE_AR_X_RX)
+#define PAGE_KERNEL __pgprot(__DIRTY_BITS | _PAGE_PL_0 | _PAGE_AR_RWX)
+#define PAGE_KERNELRX __pgprot(__ACCESS_BITS | _PAGE_PL_0 | _PAGE_AR_RX)
+#define PAGE_KERNEL_UC __pgprot(__DIRTY_BITS | _PAGE_PL_0 | _PAGE_AR_RWX | \
+ _PAGE_MA_UC)
+
+# ifndef __ASSEMBLY__
+
+#include <linux/sched/mm.h> /* for mm_struct */
+#include <linux/bitops.h>
+#include <asm/cacheflush.h>
+#include <asm/mmu_context.h>
+
+/*
+ * Next come the mappings that determine how mmap() protection bits
+ * (PROT_EXEC, PROT_READ, PROT_WRITE, PROT_NONE) get implemented. The
+ * _P version gets used for a private shared memory segment, the _S
+ * version gets used for a shared memory segment with MAP_SHARED on.
+ * In a private shared memory segment, we do a copy-on-write if a task
+ * attempts to write to the page.
+ */
+ /* xwr */
+#define __P000 PAGE_NONE
+#define __P001 PAGE_READONLY
+#define __P010 PAGE_READONLY /* write to priv pg -> copy & make writable */
+#define __P011 PAGE_READONLY /* ditto */
+#define __P100 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_X_RX)
+#define __P101 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX)
+#define __P110 PAGE_COPY_EXEC
+#define __P111 PAGE_COPY_EXEC
+
+#define __S000 PAGE_NONE
+#define __S001 PAGE_READONLY
+#define __S010 PAGE_SHARED /* we don't have (and don't need) write-only */
+#define __S011 PAGE_SHARED
+#define __S100 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_X_RX)
+#define __S101 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX)
+#define __S110 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RWX)
+#define __S111 __pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RWX)
+
+#define pgd_ERROR(e) printk("%s:%d: bad pgd %016lx.\n", __FILE__, __LINE__, pgd_val(e))
+#if CONFIG_PGTABLE_LEVELS == 4
+#define pud_ERROR(e) printk("%s:%d: bad pud %016lx.\n", __FILE__, __LINE__, pud_val(e))
+#endif
+#define pmd_ERROR(e) printk("%s:%d: bad pmd %016lx.\n", __FILE__, __LINE__, pmd_val(e))
+#define pte_ERROR(e) printk("%s:%d: bad pte %016lx.\n", __FILE__, __LINE__, pte_val(e))
+
+
+/*
+ * Some definitions to translate between mem_map, PTEs, and page addresses:
+ */
+
+
+/* Quick test to see if ADDR is a (potentially) valid physical address. */
+static inline long
+ia64_phys_addr_valid (unsigned long addr)
+{
+ return (addr & (local_cpu_data->unimpl_pa_mask)) == 0;
+}
+
+/*
+ * 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 IA-64.
+ */
+#define kern_addr_valid(addr) (1)
+
+
+/*
+ * Now come the defines and routines to manage and access the three-level
+ * page table.
+ */
+
+
+#define VMALLOC_START (RGN_BASE(RGN_GATE) + 0x200000000UL)
+#ifdef CONFIG_VIRTUAL_MEM_MAP
+# define VMALLOC_END_INIT (RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 9)))
+extern unsigned long VMALLOC_END;
+#else
+#if defined(CONFIG_SPARSEMEM) && defined(CONFIG_SPARSEMEM_VMEMMAP)
+/* SPARSEMEM_VMEMMAP uses half of vmalloc... */
+# define VMALLOC_END (RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 10)))
+# define vmemmap ((struct page *)VMALLOC_END)
+#else
+# define VMALLOC_END (RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 9)))
+#endif
+#endif
+
+/* fs/proc/kcore.c */
+#define kc_vaddr_to_offset(v) ((v) - RGN_BASE(RGN_GATE))
+#define kc_offset_to_vaddr(o) ((o) + RGN_BASE(RGN_GATE))
+
+#define RGN_MAP_SHIFT (PGDIR_SHIFT + PTRS_PER_PGD_SHIFT - 3)
+#define RGN_MAP_LIMIT ((1UL << RGN_MAP_SHIFT) - PAGE_SIZE) /* per region addr limit */
+
+/*
+ * Conversion functions: convert page frame number (pfn) and a protection value to a page
+ * table entry (pte).
+ */
+#define pfn_pte(pfn, pgprot) \
+({ pte_t __pte; pte_val(__pte) = ((pfn) << PAGE_SHIFT) | pgprot_val(pgprot); __pte; })
+
+/* Extract pfn from pte. */
+#define pte_pfn(_pte) ((pte_val(_pte) & _PFN_MASK) >> PAGE_SHIFT)
+
+#define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
+
+/* This takes a physical page address that is used by the remapping functions */
+#define mk_pte_phys(physpage, pgprot) \
+({ pte_t __pte; pte_val(__pte) = physpage + pgprot_val(pgprot); __pte; })
+
+#define pte_modify(_pte, newprot) \
+ (__pte((pte_val(_pte) & ~_PAGE_CHG_MASK) | (pgprot_val(newprot) & _PAGE_CHG_MASK)))
+
+#define pte_none(pte) (!pte_val(pte))
+#define pte_present(pte) (pte_val(pte) & (_PAGE_P | _PAGE_PROTNONE))
+#define pte_clear(mm,addr,pte) (pte_val(*(pte)) = 0UL)
+/* pte_page() returns the "struct page *" corresponding to the PTE: */
+#define pte_page(pte) virt_to_page(((pte_val(pte) & _PFN_MASK) + PAGE_OFFSET))
+
+#define pmd_none(pmd) (!pmd_val(pmd))
+#define pmd_bad(pmd) (!ia64_phys_addr_valid(pmd_val(pmd)))
+#define pmd_present(pmd) (pmd_val(pmd) != 0UL)
+#define pmd_clear(pmdp) (pmd_val(*(pmdp)) = 0UL)
+#define pmd_page_vaddr(pmd) ((unsigned long) __va(pmd_val(pmd) & _PFN_MASK))
+#define pmd_page(pmd) virt_to_page((pmd_val(pmd) + PAGE_OFFSET))
+
+#define pud_none(pud) (!pud_val(pud))
+#define pud_bad(pud) (!ia64_phys_addr_valid(pud_val(pud)))
+#define pud_present(pud) (pud_val(pud) != 0UL)
+#define pud_clear(pudp) (pud_val(*(pudp)) = 0UL)
+#define pud_page_vaddr(pud) ((unsigned long) __va(pud_val(pud) & _PFN_MASK))
+#define pud_page(pud) virt_to_page((pud_val(pud) + PAGE_OFFSET))
+
+#if CONFIG_PGTABLE_LEVELS == 4
+#define pgd_none(pgd) (!pgd_val(pgd))
+#define pgd_bad(pgd) (!ia64_phys_addr_valid(pgd_val(pgd)))
+#define pgd_present(pgd) (pgd_val(pgd) != 0UL)
+#define pgd_clear(pgdp) (pgd_val(*(pgdp)) = 0UL)
+#define pgd_page_vaddr(pgd) ((unsigned long) __va(pgd_val(pgd) & _PFN_MASK))
+#define pgd_page(pgd) virt_to_page((pgd_val(pgd) + PAGE_OFFSET))
+#endif
+
+/*
+ * The following have defined behavior only work if pte_present() is true.
+ */
+#define pte_write(pte) ((unsigned) (((pte_val(pte) & _PAGE_AR_MASK) >> _PAGE_AR_SHIFT) - 2) <= 4)
+#define pte_exec(pte) ((pte_val(pte) & _PAGE_AR_RX) != 0)
+#define pte_dirty(pte) ((pte_val(pte) & _PAGE_D) != 0)
+#define pte_young(pte) ((pte_val(pte) & _PAGE_A) != 0)
+#define pte_special(pte) 0
+
+/*
+ * Note: we convert AR_RWX to AR_RX and AR_RW to AR_R by clearing the 2nd bit in the
+ * access rights:
+ */
+#define pte_wrprotect(pte) (__pte(pte_val(pte) & ~_PAGE_AR_RW))
+#define pte_mkwrite(pte) (__pte(pte_val(pte) | _PAGE_AR_RW))
+#define pte_mkold(pte) (__pte(pte_val(pte) & ~_PAGE_A))
+#define pte_mkyoung(pte) (__pte(pte_val(pte) | _PAGE_A))
+#define pte_mkclean(pte) (__pte(pte_val(pte) & ~_PAGE_D))
+#define pte_mkdirty(pte) (__pte(pte_val(pte) | _PAGE_D))
+#define pte_mkhuge(pte) (__pte(pte_val(pte)))
+#define pte_mkspecial(pte) (pte)
+
+/*
+ * Because ia64's Icache and Dcache is not coherent (on a cpu), we need to
+ * sync icache and dcache when we insert *new* executable page.
+ * __ia64_sync_icache_dcache() check Pg_arch_1 bit and flush icache
+ * if necessary.
+ *
+ * set_pte() is also called by the kernel, but we can expect that the kernel
+ * flushes icache explicitly if necessary.
+ */
+#define pte_present_exec_user(pte)\
+ ((pte_val(pte) & (_PAGE_P | _PAGE_PL_MASK | _PAGE_AR_RX)) == \
+ (_PAGE_P | _PAGE_PL_3 | _PAGE_AR_RX))
+
+extern void __ia64_sync_icache_dcache(pte_t pteval);
+static inline void set_pte(pte_t *ptep, pte_t pteval)
+{
+ /* page is present && page is user && page is executable
+ * && (page swapin or new page or page migraton
+ * || copy_on_write with page copying.)
+ */
+ if (pte_present_exec_user(pteval) &&
+ (!pte_present(*ptep) ||
+ pte_pfn(*ptep) != pte_pfn(pteval)))
+ /* load_module() calles flush_icache_range() explicitly*/
+ __ia64_sync_icache_dcache(pteval);
+ *ptep = pteval;
+}
+
+#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
+
+/*
+ * Make page protection values cacheable, uncacheable, or write-
+ * combining. Note that "protection" is really a misnomer here as the
+ * protection value contains the memory attribute bits, dirty bits, and
+ * various other bits as well.
+ */
+#define pgprot_cacheable(prot) __pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_WB)
+#define pgprot_noncached(prot) __pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_UC)
+#define pgprot_writecombine(prot) __pgprot((pgprot_val(prot) & ~_PAGE_MA_MASK) | _PAGE_MA_WC)
+
+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
+
+static inline unsigned long
+pgd_index (unsigned long address)
+{
+ unsigned long region = address >> 61;
+ unsigned long l1index = (address >> PGDIR_SHIFT) & ((PTRS_PER_PGD >> 3) - 1);
+
+ return (region << (PAGE_SHIFT - 6)) | l1index;
+}
+
+/* The offset in the 1-level directory is given by the 3 region bits
+ (61..63) and the level-1 bits. */
+static inline pgd_t*
+pgd_offset (const struct mm_struct *mm, unsigned long address)
+{
+ return mm->pgd + pgd_index(address);
+}
+
+/* In the kernel's mapped region we completely ignore the region number
+ (since we know it's in region number 5). */
+#define pgd_offset_k(addr) \
+ (init_mm.pgd + (((addr) >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1)))
+
+/* Look up a pgd entry in the gate area. On IA-64, the gate-area
+ resides in the kernel-mapped segment, hence we use pgd_offset_k()
+ here. */
+#define pgd_offset_gate(mm, addr) pgd_offset_k(addr)
+
+#if CONFIG_PGTABLE_LEVELS == 4
+/* Find an entry in the second-level page table.. */
+#define pud_offset(dir,addr) \
+ ((pud_t *) pgd_page_vaddr(*(dir)) + (((addr) >> PUD_SHIFT) & (PTRS_PER_PUD - 1)))
+#endif
+
+/* Find an entry in the third-level page table.. */
+#define pmd_offset(dir,addr) \
+ ((pmd_t *) pud_page_vaddr(*(dir)) + (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)))
+
+/*
+ * Find an entry in the third-level page table. This looks more complicated than it
+ * should be because some platforms place page tables in high memory.
+ */
+#define pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
+#define pte_offset_kernel(dir,addr) ((pte_t *) pmd_page_vaddr(*(dir)) + pte_index(addr))
+#define pte_offset_map(dir,addr) pte_offset_kernel(dir, addr)
+#define pte_unmap(pte) do { } while (0)
+
+/* atomic versions of the some PTE manipulations: */
+
+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(_PAGE_A_BIT, 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
+}
+
+static inline pte_t
+ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
+{
+#ifdef CONFIG_SMP
+ return __pte(xchg((long *) ptep, 0));
+#else
+ pte_t pte = *ptep;
+ pte_clear(mm, addr, ptep);
+ return pte;
+#endif
+}
+
+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
+}
+
+static inline int
+pte_same (pte_t a, pte_t b)
+{
+ return pte_val(a) == pte_val(b);
+}
+
+#define update_mmu_cache(vma, address, ptep) do { } while (0)
+
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+extern void paging_init (void);
+
+/*
+ * Note: The macros below rely on the fact that MAX_SWAPFILES_SHIFT <= number of
+ * bits in the swap-type field of the swap pte. It would be nice to
+ * enforce that, but we can't easily include <linux/swap.h> here.
+ * (Of course, better still would be to define MAX_SWAPFILES_SHIFT here...).
+ *
+ * Format of swap pte:
+ * bit 0 : present bit (must be zero)
+ * bits 1- 7: swap-type
+ * bits 8-62: swap offset
+ * bit 63 : _PAGE_PROTNONE bit
+ */
+#define __swp_type(entry) (((entry).val >> 1) & 0x7f)
+#define __swp_offset(entry) (((entry).val << 1) >> 9)
+#define __swp_entry(type,offset) ((swp_entry_t) { ((type) << 1) | ((long) (offset) << 8) })
+#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
+#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
+
+/*
+ * 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)];
+extern struct page *zero_page_memmap_ptr;
+#define ZERO_PAGE(vaddr) (zero_page_memmap_ptr)
+
+/* We provide our own get_unmapped_area to cope with VA holes for userland */
+#define HAVE_ARCH_UNMAPPED_AREA
+
+#ifdef CONFIG_HUGETLB_PAGE
+#define HUGETLB_PGDIR_SHIFT (HPAGE_SHIFT + 2*(PAGE_SHIFT-3))
+#define HUGETLB_PGDIR_SIZE (__IA64_UL(1) << HUGETLB_PGDIR_SHIFT)
+#define HUGETLB_PGDIR_MASK (~(HUGETLB_PGDIR_SIZE-1))
+#endif
+
+
+#define __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS
+/*
+ * Update PTEP with ENTRY, which is guaranteed to be a less
+ * restrictive PTE. That is, ENTRY may have the ACCESSED, DIRTY, and
+ * WRITABLE bits turned on, when the value at PTEP did not. The
+ * WRITABLE bit may only be turned if SAFELY_WRITABLE is TRUE.
+ *
+ * SAFELY_WRITABLE is TRUE if we can update the value at PTEP without
+ * having to worry about races. On SMP machines, there are only two
+ * cases where this is true:
+ *
+ * (1) *PTEP has the PRESENT bit turned OFF
+ * (2) ENTRY has the DIRTY bit turned ON
+ *
+ * On ia64, we could implement this routine with a cmpxchg()-loop
+ * which ORs in the _PAGE_A/_PAGE_D bit if they're set in ENTRY.
+ * However, like on x86, we can get a more streamlined version by
+ * observing that it is OK to drop ACCESSED bit updates when
+ * SAFELY_WRITABLE is FALSE. Besides being rare, all that would do is
+ * result in an extra Access-bit fault, which would then turn on the
+ * ACCESSED bit in the low-level fault handler (iaccess_bit or
+ * daccess_bit in ivt.S).
+ */
+#ifdef CONFIG_SMP
+# define ptep_set_access_flags(__vma, __addr, __ptep, __entry, __safely_writable) \
+({ \
+ int __changed = !pte_same(*(__ptep), __entry); \
+ if (__changed && __safely_writable) { \
+ set_pte(__ptep, __entry); \
+ flush_tlb_page(__vma, __addr); \
+ } \
+ __changed; \
+})
+#else
+# define ptep_set_access_flags(__vma, __addr, __ptep, __entry, __safely_writable) \
+({ \
+ int __changed = !pte_same(*(__ptep), __entry); \
+ if (__changed) { \
+ set_pte_at((__vma)->vm_mm, (__addr), __ptep, __entry); \
+ flush_tlb_page(__vma, __addr); \
+ } \
+ __changed; \
+})
+#endif
+
+# ifdef CONFIG_VIRTUAL_MEM_MAP
+ /* arch mem_map init routine is needed due to holes in a virtual mem_map */
+# define __HAVE_ARCH_MEMMAP_INIT
+ extern void memmap_init (unsigned long size, int nid, unsigned long zone,
+ unsigned long start_pfn);
+# endif /* CONFIG_VIRTUAL_MEM_MAP */
+# endif /* !__ASSEMBLY__ */
+
+/*
+ * Identity-mapped regions use a large page size. We'll call such large pages
+ * "granules". If you can think of a better name that's unambiguous, let me
+ * know...
+ */
+#if defined(CONFIG_IA64_GRANULE_64MB)
+# define IA64_GRANULE_SHIFT _PAGE_SIZE_64M
+#elif defined(CONFIG_IA64_GRANULE_16MB)
+# define IA64_GRANULE_SHIFT _PAGE_SIZE_16M
+#endif
+#define IA64_GRANULE_SIZE (1 << IA64_GRANULE_SHIFT)
+/*
+ * log2() of the page size we use to map the kernel image (IA64_TR_KERNEL):
+ */
+#define KERNEL_TR_PAGE_SHIFT _PAGE_SIZE_64M
+#define KERNEL_TR_PAGE_SIZE (1 << KERNEL_TR_PAGE_SHIFT)
+
+/*
+ * No page table caches to initialise
+ */
+#define pgtable_cache_init() do { } while (0)
+
+/* These tell get_user_pages() that the first gate page is accessible from user-level. */
+#define FIXADDR_USER_START GATE_ADDR
+#ifdef HAVE_BUGGY_SEGREL
+# define FIXADDR_USER_END (GATE_ADDR + 2*PAGE_SIZE)
+#else
+# define FIXADDR_USER_END (GATE_ADDR + 2*PERCPU_PAGE_SIZE)
+#endif
+
+#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
+#define __HAVE_ARCH_PGD_OFFSET_GATE
+
+
+#if CONFIG_PGTABLE_LEVELS == 3
+#define __ARCH_USE_5LEVEL_HACK
+#include <asm-generic/pgtable-nopud.h>
+#endif
+#include <asm-generic/5level-fixup.h>
+#include <asm-generic/pgtable.h>
+
+#endif /* _ASM_IA64_PGTABLE_H */