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 pmd_t *get_pmd(void)
  22 {
  23         return (pmd_t *)get_zeroed_page(GFP_KERNEL);
  24 }
  25
  26 static inline void pmd_free(pmd_t *pmd)
  27 {
  28         BUG_ON((unsigned long)pmd & (PAGE_SIZE-1));
  29         free_page((unsigned long)pmd);
  30 }
  31
  32 static inline pmd_t *pmd_alloc_one (struct mm_struct *mm, unsigned long addr)
  33 {
  34         return (pmd_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
  35 }
  36
  37 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
  38 {
  39         return (pud_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
  40 }
  41
  42 static inline void pud_free (pud_t *pud)
  43 {
  44         BUG_ON((unsigned long)pud & (PAGE_SIZE-1));
  45         free_page((unsigned long)pud);
  46 }
  47
  48 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
  49 {
  50         unsigned boundary;
  51         pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT);
  52         if (!pgd)
  53                 return NULL;
  54         /*
  55          * Copy kernel pointers in from init.
  56          * Could keep a freelist or slab cache of those because the kernel
  57          * part never changes.
  58          */
  59         boundary = pgd_index(__PAGE_OFFSET);
  60         memset(pgd, 0, boundary * sizeof(pgd_t));
  61         memcpy(pgd + boundary,
  62                init_level4_pgt + boundary,
  63                (PTRS_PER_PGD - boundary) * sizeof(pgd_t));
  64         return pgd;
  65 }
  66
  67 static inline void pgd_free(pgd_t *pgd)
  68 {
  69         BUG_ON((unsigned long)pgd & (PAGE_SIZE-1));
  70         free_page((unsigned long)pgd);
  71 }
  72
  73 static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
  74 {
  75         return (pte_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
  76 }
  77
  78 static inline struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
  79 {
  80         void *p = (void *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
  81         if (!p)
  82                 return NULL;
  83         return virt_to_page(p);
  84 }
  85
  86 /* Should really implement gc for free page table pages. This could be
  87    done with a reference count in struct page. */
  88
  89 static inline void pte_free_kernel(pte_t *pte)
  90 {
  91         BUG_ON((unsigned long)pte & (PAGE_SIZE-1));
  92         free_page((unsigned long)pte);
  93 }
  94
  95 static inline void pte_free(struct page *pte)
  96 {
  97         __free_page(pte);
  98 }
  99
 100 #define __pte_free_tlb(tlb,pte) tlb_remove_page((tlb),(pte))
 101
 102 #define __pmd_free_tlb(tlb,x)   tlb_remove_page((tlb),virt_to_page(x))
 103 #define __pud_free_tlb(tlb,x)   tlb_remove_page((tlb),virt_to_page(x))
 104
 105 #endif /* _X86_64_PGALLOC_H */