include/asm-x86/pgalloc_32.h

   1 #ifndef _I386_PGALLOC_H
   2 #define _I386_PGALLOC_H
   3
   4 #include <linux/threads.h>
   5 #include <linux/mm.h>           /* for struct page */
   6 #include <linux/pagemap.h>
   7 #include <asm/tlb.h>
   8 #include <asm-generic/tlb.h>
   9
  10 #ifdef CONFIG_PARAVIRT
  11 #include <asm/paravirt.h>
  12 #else
  13 #define paravirt_alloc_pt(mm, pfn) do { } while (0)
  14 #define paravirt_alloc_pd(mm, pfn) do { } while (0)
  15 #define paravirt_alloc_pd_clone(pfn, clonepfn, start, count) do { } while (0)
  16 #define paravirt_release_pt(pfn) do { } while (0)
  17 #define paravirt_release_pd(pfn) do { } while (0)
  18 #endif
  19
  20 static inline void pmd_populate_kernel(struct mm_struct *mm,
  21                                        pmd_t *pmd, pte_t *pte)
  22 {
  23         paravirt_alloc_pt(mm, __pa(pte) >> PAGE_SHIFT);
  24         set_pmd(pmd, __pmd(__pa(pte) | _PAGE_TABLE));
  25 }
  26
  27 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd, struct page *pte)
  28 {
  29         unsigned long pfn = page_to_pfn(pte);
  30
  31         paravirt_alloc_pt(mm, pfn);
  32         set_pmd(pmd, __pmd(((pteval_t)pfn << PAGE_SHIFT) | _PAGE_TABLE));
  33 }
  34 #define pmd_pgtable(pmd) pmd_page(pmd)
  35
  36 /*
  37  * Allocate and free page tables.
  38  */
  39 extern pgd_t *pgd_alloc(struct mm_struct *);
  40 extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
  41
  42 extern pte_t *pte_alloc_one_kernel(struct mm_struct *, unsigned long);
  43 extern pgtable_t pte_alloc_one(struct mm_struct *, unsigned long);
  44
  45 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
  46 {
  47         free_page((unsigned long)pte);
  48 }
  49
  50 static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
  51 {
  52         pgtable_page_dtor(pte);
  53         __free_page(pte);
  54 }
  55
  56
  57 extern void __pte_free_tlb(struct mmu_gather *tlb, struct page *pte);
  58
  59 #ifdef CONFIG_X86_PAE
  60 /*
  61  * In the PAE case we free the pmds as part of the pgd.
  62  */
  63 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
  64 {
  65         return (pmd_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
  66 }
  67
  68 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
  69 {
  70         BUG_ON((unsigned long)pmd & (PAGE_SIZE-1));
  71         free_page((unsigned long)pmd);
  72 }
  73
  74 extern void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd);
  75
  76 static inline void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmd)
  77 {
  78         paravirt_alloc_pd(mm, __pa(pmd) >> PAGE_SHIFT);
  79
  80         /* Note: almost everything apart from _PAGE_PRESENT is
  81            reserved at the pmd (PDPT) level. */
  82         set_pud(pudp, __pud(__pa(pmd) | _PAGE_PRESENT));
  83
  84         /*
  85          * According to Intel App note "TLBs, Paging-Structure Caches,
  86          * and Their Invalidation", April 2007, document 317080-001,
  87          * section 8.1: in PAE mode we explicitly have to flush the
  88          * TLB via cr3 if the top-level pgd is changed...
  89          */
  90         if (mm == current->active_mm)
  91                 write_cr3(read_cr3());
  92 }
  93 #endif  /* CONFIG_X86_PAE */
  94
  95 #endif /* _I386_PGALLOC_H */