include/asm-x86_64/pgalloc.h

   1 #ifndef _X86_64_PGALLOC_H
   2 #define _X86_64_PGALLOC_H
   3
   4 #include <asm/fixmap.h>
   5 #include <asm/pda.h>
   6 #include <linux/threads.h>
   7 #include <linux/mm.h>
   8
   9 #define pmd_populate_kernel(mm, pmd, pte) \
  10                 set_pmd(pmd, __pmd(_PAGE_TABLE | __pa(pte)))
  11 #define pud_populate(mm, pud, pmd) \
  12                 set_pud(pud, __pud(_PAGE_TABLE | __pa(pmd)))
  13 #define pgd_populate(mm, pgd, pud) \
  14                 set_pgd(pgd, __pgd(_PAGE_TABLE | __pa(pud)))
  15
  16 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd, struct page *pte)
  17 {
  18         set_pmd(pmd, __pmd(_PAGE_TABLE | (page_to_pfn(pte) << PAGE_SHIFT)));
  19 }
  20
  21 static inline void pmd_free(pmd_t *pmd)
  22 {
  23         BUG_ON((unsigned long)pmd & (PAGE_SIZE-1));
  24         free_page((unsigned long)pmd);
  25 }
  26
  27 static inline pmd_t *pmd_alloc_one (struct mm_struct *mm, unsigned long addr)
  28 {
  29         return (pmd_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
  30 }
  31
  32 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
  33 {
  34         return (pud_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
  35 }
  36
  37 static inline void pud_free (pud_t *pud)
  38 {
  39         BUG_ON((unsigned long)pud & (PAGE_SIZE-1));
  40         free_page((unsigned long)pud);
  41 }
  42
  43 static inline void pgd_list_add(pgd_t *pgd)
  44 {
  45         struct page *page = virt_to_page(pgd);
  46
  47         spin_lock(&pgd_lock);
  48         page->index = (pgoff_t)pgd_list;
  49         if (pgd_list)
  50                 pgd_list->private = (unsigned long)&page->index;
  51         pgd_list = page;
  52         page->private = (unsigned long)&pgd_list;
  53         spin_unlock(&pgd_lock);
  54 }
  55
  56 static inline void pgd_list_del(pgd_t *pgd)
  57 {
  58         struct page *next, **pprev, *page = virt_to_page(pgd);
  59
  60         spin_lock(&pgd_lock);
  61         next = (struct page *)page->index;
  62         pprev = (struct page **)page->private;
  63         *pprev = next;
  64         if (next)
  65                 next->private = (unsigned long)pprev;
  66         spin_unlock(&pgd_lock);
  67 }
  68
  69 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
  70 {
  71         unsigned boundary;
  72         pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT);
  73         if (!pgd)
  74                 return NULL;
  75         pgd_list_add(pgd);
  76         /*
  77          * Copy kernel pointers in from init.
  78          * Could keep a freelist or slab cache of those because the kernel
  79          * part never changes.
  80          */
  81         boundary = pgd_index(__PAGE_OFFSET);
  82         memset(pgd, 0, boundary * sizeof(pgd_t));
  83         memcpy(pgd + boundary,
  84                init_level4_pgt + boundary,
  85                (PTRS_PER_PGD - boundary) * sizeof(pgd_t));
  86         return pgd;
  87 }
  88
  89 static inline void pgd_free(pgd_t *pgd)
  90 {
  91         BUG_ON((unsigned long)pgd & (PAGE_SIZE-1));
  92         pgd_list_del(pgd);
  93         free_page((unsigned long)pgd);
  94 }
  95
  96 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
  97 {
  98         return (pte_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
  99 }
 100
 101 static inline struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
 102 {
 103         void *p = (void *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
 104         if (!p)
 105                 return NULL;
 106         return virt_to_page(p);
 107 }
 108
 109 /* Should really implement gc for free page table pages. This could be
 110    done with a reference count in struct page. */
 111
 112 static inline void pte_free_kernel(pte_t *pte)
 113 {
 114         BUG_ON((unsigned long)pte & (PAGE_SIZE-1));
 115         free_page((unsigned long)pte);
 116 }
 117
 118 static inline void pte_free(struct page *pte)
 119 {
 120         __free_page(pte);
 121 }
 122
 123 #define __pte_free_tlb(tlb,pte) tlb_remove_page((tlb),(pte))
 124
 125 #define __pmd_free_tlb(tlb,x)   tlb_remove_page((tlb),virt_to_page(x))
 126 #define __pud_free_tlb(tlb,x)   tlb_remove_page((tlb),virt_to_page(x))
 127
 128 #endif /* _X86_64_PGALLOC_H */