include/linux/pfn_t.h

   1 #ifndef _LINUX_PFN_T_H_
   2 #define _LINUX_PFN_T_H_
   3 #include <linux/mm.h>
   4
   5 /*
   6  * PFN_FLAGS_MASK - mask of all the possible valid pfn_t flags
   7  * PFN_SG_CHAIN - pfn is a pointer to the next scatterlist entry
   8  * PFN_SG_LAST - pfn references a page and is the last scatterlist entry
   9  * PFN_DEV - pfn is not covered by system memmap by default
  10  * PFN_MAP - pfn has a dynamic page mapping established by a device driver
  11  */
  12 #define PFN_FLAGS_MASK (((u64) ~PAGE_MASK) << (BITS_PER_LONG_LONG - PAGE_SHIFT))
  13 #define PFN_SG_CHAIN (1ULL << (BITS_PER_LONG_LONG - 1))
  14 #define PFN_SG_LAST (1ULL << (BITS_PER_LONG_LONG - 2))
  15 #define PFN_DEV (1ULL << (BITS_PER_LONG_LONG - 3))
  16 #define PFN_MAP (1ULL << (BITS_PER_LONG_LONG - 4))
  17
  18 #define PFN_FLAGS_TRACE \
  19         { PFN_SG_CHAIN, "SG_CHAIN" }, \
  20         { PFN_SG_LAST,  "SG_LAST" }, \
  21         { PFN_DEV,      "DEV" }, \
  22         { PFN_MAP,      "MAP" }
  23
  24 static inline pfn_t __pfn_to_pfn_t(unsigned long pfn, u64 flags)
  25 {
  26         pfn_t pfn_t = { .val = pfn | (flags & PFN_FLAGS_MASK), };
  27
  28         return pfn_t;
  29 }
  30
  31 /* a default pfn to pfn_t conversion assumes that @pfn is pfn_valid() */
  32 static inline pfn_t pfn_to_pfn_t(unsigned long pfn)
  33 {
  34         return __pfn_to_pfn_t(pfn, 0);
  35 }
  36
  37 static inline pfn_t phys_to_pfn_t(phys_addr_t addr, u64 flags)
  38 {
  39         return __pfn_to_pfn_t(addr >> PAGE_SHIFT, flags);
  40 }
  41
  42 static inline bool pfn_t_has_page(pfn_t pfn)
  43 {
  44         return (pfn.val & PFN_MAP) == PFN_MAP || (pfn.val & PFN_DEV) == 0;
  45 }
  46
  47 static inline unsigned long pfn_t_to_pfn(pfn_t pfn)
  48 {
  49         return pfn.val & ~PFN_FLAGS_MASK;
  50 }
  51
  52 static inline struct page *pfn_t_to_page(pfn_t pfn)
  53 {
  54         if (pfn_t_has_page(pfn))
  55                 return pfn_to_page(pfn_t_to_pfn(pfn));
  56         return NULL;
  57 }
  58
  59 static inline phys_addr_t pfn_t_to_phys(pfn_t pfn)
  60 {
  61         return PFN_PHYS(pfn_t_to_pfn(pfn));
  62 }
  63
  64 static inline void *pfn_t_to_virt(pfn_t pfn)
  65 {
  66         if (pfn_t_has_page(pfn))
  67                 return __va(pfn_t_to_phys(pfn));
  68         return NULL;
  69 }
  70
  71 static inline pfn_t page_to_pfn_t(struct page *page)
  72 {
  73         return pfn_to_pfn_t(page_to_pfn(page));
  74 }
  75
  76 static inline int pfn_t_valid(pfn_t pfn)
  77 {
  78         return pfn_valid(pfn_t_to_pfn(pfn));
  79 }
  80
  81 #ifdef CONFIG_MMU
  82 static inline pte_t pfn_t_pte(pfn_t pfn, pgprot_t pgprot)
  83 {
  84         return pfn_pte(pfn_t_to_pfn(pfn), pgprot);
  85 }
  86 #endif
  87
  88 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
  89 static inline pmd_t pfn_t_pmd(pfn_t pfn, pgprot_t pgprot)
  90 {
  91         return pfn_pmd(pfn_t_to_pfn(pfn), pgprot);
  92 }
  93
  94 #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
  95 static inline pud_t pfn_t_pud(pfn_t pfn, pgprot_t pgprot)
  96 {
  97         return pfn_pud(pfn_t_to_pfn(pfn), pgprot);
  98 }
  99 #endif
 100 #endif
 101
 102 #ifdef __HAVE_ARCH_PTE_DEVMAP
 103 static inline bool pfn_t_devmap(pfn_t pfn)
 104 {
 105         const u64 flags = PFN_DEV|PFN_MAP;
 106
 107         return (pfn.val & flags) == flags;
 108 }
 109 #else
 110 static inline bool pfn_t_devmap(pfn_t pfn)
 111 {
 112         return false;
 113 }
 114 pte_t pte_mkdevmap(pte_t pte);
 115 pmd_t pmd_mkdevmap(pmd_t pmd);
 116 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) && \
 117         defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)
 118 pud_t pud_mkdevmap(pud_t pud);
 119 #endif
 120 #endif /* __HAVE_ARCH_PTE_DEVMAP */
 121
 122 #endif /* _LINUX_PFN_T_H_ */