include/asm-x86_64/pgalloc.h

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