LXR linux/include/linux/pfn

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _LINUX_PFN_T_H_
   3#define _LINUX_PFN_T_H_
   4#include <linux/mm.h>
   5
   6/*
   7 * PFN_FLAGS_MASK - mask of all the possible valid pfn_t flags
   8 * PFN_SG_CHAIN - pfn is a pointer to the next scatterlist entry
   9 * PFN_SG_LAST - pfn references a page and is the last scatterlist entry
  10 * PFN_DEV - pfn is not covered by system memmap by default
  11 * PFN_MAP - pfn has a dynamic page mapping established by a device driver
  12 */
  13#define PFN_FLAGS_MASK (((u64) ~PAGE_MASK) << (BITS_PER_LONG_LONG - PAGE_SHIFT))
  14#define PFN_SG_CHAIN (1ULL << (BITS_PER_LONG_LONG - 1))
  15#define PFN_SG_LAST (1ULL << (BITS_PER_LONG_LONG - 2))
  16#define PFN_DEV (1ULL << (BITS_PER_LONG_LONG - 3))
  17#define PFN_MAP (1ULL << (BITS_PER_LONG_LONG - 4))
  18
  19#define PFN_FLAGS_TRACE \
  20        { PFN_SG_CHAIN, "SG_CHAIN" }, \
  21        { PFN_SG_LAST,  "SG_LAST" }, \
  22        { PFN_DEV,      "DEV" }, \
  23        { PFN_MAP,      "MAP" }
  24
  25static inline pfn_t __pfn_to_pfn_t(unsigned long pfn, u64 flags)
  26{
  27        pfn_t pfn_t = { .val = pfn | (flags & PFN_FLAGS_MASK), };
  28
  29        return pfn_t;
  30}
  31
  32/* a default pfn to pfn_t conversion assumes that @pfn is pfn_valid() */
  33static inline pfn_t pfn_to_pfn_t(unsigned long pfn)
  34{
  35        return __pfn_to_pfn_t(pfn, 0);
  36}
  37
  38static inline pfn_t phys_to_pfn_t(phys_addr_t addr, u64 flags)
  39{
  40        return __pfn_to_pfn_t(addr >> PAGE_SHIFT, flags);
  41}
  42
  43static inline bool pfn_t_has_page(pfn_t pfn)
  44{
  45        return (pfn.val & PFN_MAP) == PFN_MAP || (pfn.val & PFN_DEV) == 0;
  46}
  47
  48static inline unsigned long pfn_t_to_pfn(pfn_t pfn)
  49{
  50        return pfn.val & ~PFN_FLAGS_MASK;
  51}
  52
  53static inline struct page *pfn_t_to_page(pfn_t pfn)
  54{
  55        if (pfn_t_has_page(pfn))
  56                return pfn_to_page(pfn_t_to_pfn(pfn));
  57        return NULL;
  58}
  59
  60static inline phys_addr_t pfn_t_to_phys(pfn_t pfn)
  61{
  62        return PFN_PHYS(pfn_t_to_pfn(pfn));
  63}
  64
  65static inline void *pfn_t_to_virt(pfn_t pfn)
  66{
  67        if (pfn_t_has_page(pfn))
  68                return __va(pfn_t_to_phys(pfn));
  69        return NULL;
  70}
  71
  72static inline pfn_t page_to_pfn_t(struct page *page)
  73{
  74        return pfn_to_pfn_t(page_to_pfn(page));
  75}
  76
  77static inline int pfn_t_valid(pfn_t pfn)
  78{
  79        return pfn_valid(pfn_t_to_pfn(pfn));
  80}
  81
  82#ifdef CONFIG_MMU
  83static inline pte_t pfn_t_pte(pfn_t pfn, pgprot_t pgprot)
  84{
  85        return pfn_pte(pfn_t_to_pfn(pfn), pgprot);
  86}
  87#endif
  88
  89#ifdef CONFIG_TRANSPARENT_HUGEPAGE
  90static inline pmd_t pfn_t_pmd(pfn_t pfn, pgprot_t pgprot)
  91{
  92        return pfn_pmd(pfn_t_to_pfn(pfn), pgprot);
  93}
  94
  95#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
  96static inline pud_t pfn_t_pud(pfn_t pfn, pgprot_t pgprot)
  97{
  98        return pfn_pud(pfn_t_to_pfn(pfn), pgprot);
  99}
 100#endif
 101#endif
 102
 103#ifdef __HAVE_ARCH_PTE_DEVMAP
 104static inline bool pfn_t_devmap(pfn_t pfn)
 105{
 106        const u64 flags = PFN_DEV|PFN_MAP;
 107
 108        return (pfn.val & flags) == flags;
 109}
 110#else
 111static inline bool pfn_t_devmap(pfn_t pfn)
 112{
 113        return false;
 114}
 115pte_t pte_mkdevmap(pte_t pte);
 116pmd_t pmd_mkdevmap(pmd_t pmd);
 117#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && \
 118        defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)
 119pud_t pud_mkdevmap(pud_t pud);
 120#endif
 121#endif /* __HAVE_ARCH_PTE_DEVMAP */
 122
 123#endif /* _LINUX_PFN_T_H_ */
 124