include/asm-ia64/pgalloc.h

   1 #ifndef _ASM_IA64_PGALLOC_H
   2 #define _ASM_IA64_PGALLOC_H
   3
   4 /*
   5  * This file contains the functions and defines necessary to allocate
   6  * page tables.
   7  *
   8  * This hopefully works with any (fixed) ia-64 page-size, as defined
   9  * in <asm/page.h> (currently 8192).
  10  *
  11  * Copyright (C) 1998-2001 Hewlett-Packard Co
  12  *      David Mosberger-Tang <davidm@hpl.hp.com>
  13  * Copyright (C) 2000, Goutham Rao <goutham.rao@intel.com>
  14  */
  15
  16 #include <linux/config.h>
  17
  18 #include <linux/compiler.h>
  19 #include <linux/mm.h>
  20 #include <linux/page-flags.h>
  21 #include <linux/threads.h>
  22
  23 #include <asm/mmu_context.h>
  24
  25 /*
  26  * Very stupidly, we used to get new pgd's and pmd's, init their contents
  27  * to point to the NULL versions of the next level page table, later on
  28  * completely re-init them the same way, then free them up.  This wasted
  29  * a lot of work and caused unnecessary memory traffic.  How broken...
  30  * We fix this by caching them.
  31  */
  32 #define pgd_quicklist           (local_cpu_data->pgd_quick)
  33 #define pmd_quicklist           (local_cpu_data->pmd_quick)
  34 #define pgtable_cache_size      (local_cpu_data->pgtable_cache_sz)
  35
  36 static inline pgd_t*
  37 pgd_alloc_one_fast (struct mm_struct *mm)
  38 {
  39         unsigned long *ret = NULL;
  40
  41         preempt_disable();
  42
  43         ret = pgd_quicklist;
  44         if (likely(ret != NULL)) {
  45                 pgd_quicklist = (unsigned long *)(*ret);
  46                 ret[0] = 0;
  47                 --pgtable_cache_size;
  48         } else
  49                 ret = NULL;
  50
  51         preempt_enable();
  52
  53         return (pgd_t *) ret;
  54 }
  55
  56 static inline pgd_t*
  57 pgd_alloc (struct mm_struct *mm)
  58 {
  59         /* the VM system never calls pgd_alloc_one_fast(), so we do it here. */
  60         pgd_t *pgd = pgd_alloc_one_fast(mm);
  61
  62         if (unlikely(pgd == NULL)) {
  63                 pgd = (pgd_t *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
  64         }
  65         return pgd;
  66 }
  67
  68 static inline void
  69 pgd_free (pgd_t *pgd)
  70 {
  71         preempt_disable();
  72         *(unsigned long *)pgd = (unsigned long) pgd_quicklist;
  73         pgd_quicklist = (unsigned long *) pgd;
  74         ++pgtable_cache_size;
  75         preempt_enable();
  76 }
  77
  78 static inline void
  79 pud_populate (struct mm_struct *mm, pud_t *pud_entry, pmd_t *pmd)
  80 {
  81         pud_val(*pud_entry) = __pa(pmd);
  82 }
  83
  84 static inline pmd_t*
  85 pmd_alloc_one_fast (struct mm_struct *mm, unsigned long addr)
  86 {
  87         unsigned long *ret = NULL;
  88
  89         preempt_disable();
  90
  91         ret = (unsigned long *)pmd_quicklist;
  92         if (likely(ret != NULL)) {
  93                 pmd_quicklist = (unsigned long *)(*ret);
  94                 ret[0] = 0;
  95                 --pgtable_cache_size;
  96         }
  97
  98         preempt_enable();
  99
 100         return (pmd_t *)ret;
 101 }
 102
 103 static inline pmd_t*
 104 pmd_alloc_one (struct mm_struct *mm, unsigned long addr)
 105 {
 106         pmd_t *pmd = (pmd_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
 107
 108         return pmd;
 109 }
 110
 111 static inline void
 112 pmd_free (pmd_t *pmd)
 113 {
 114         preempt_disable();
 115         *(unsigned long *)pmd = (unsigned long) pmd_quicklist;
 116         pmd_quicklist = (unsigned long *) pmd;
 117         ++pgtable_cache_size;
 118         preempt_enable();
 119 }
 120
 121 #define __pmd_free_tlb(tlb, pmd)        pmd_free(pmd)
 122
 123 static inline void
 124 pmd_populate (struct mm_struct *mm, pmd_t *pmd_entry, struct page *pte)
 125 {
 126         pmd_val(*pmd_entry) = page_to_phys(pte);
 127 }
 128
 129 static inline void
 130 pmd_populate_kernel (struct mm_struct *mm, pmd_t *pmd_entry, pte_t *pte)
 131 {
 132         pmd_val(*pmd_entry) = __pa(pte);
 133 }
 134
 135 static inline struct page *
 136 pte_alloc_one (struct mm_struct *mm, unsigned long addr)
 137 {
 138         struct page *pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, 0);
 139
 140         return pte;
 141 }
 142
 143 static inline pte_t *
 144 pte_alloc_one_kernel (struct mm_struct *mm, unsigned long addr)
 145 {
 146         pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
 147
 148         return pte;
 149 }
 150
 151 static inline void
 152 pte_free (struct page *pte)
 153 {
 154         __free_page(pte);
 155 }
 156
 157 static inline void
 158 pte_free_kernel (pte_t *pte)
 159 {
 160         free_page((unsigned long) pte);
 161 }
 162
 163 #define __pte_free_tlb(tlb, pte)        tlb_remove_page((tlb), (pte))
 164
 165 extern void check_pgt_cache (void);
 166
 167 #endif /* _ASM_IA64_PGALLOC_H */