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 * PFN_SPECIAL - for CONFIG_FS_DAX_LIMITED builds to allow XIP, but not
  13 *               get_user_pages
  14 */
  15#define PFN_FLAGS_MASK (((u64) (~PAGE_MASK)) << (BITS_PER_LONG_LONG - PAGE_SHIFT))
  16#define PFN_SG_CHAIN (1ULL << (BITS_PER_LONG_LONG - 1))
  17#define PFN_SG_LAST (1ULL << (BITS_PER_LONG_LONG - 2))
  18#define PFN_DEV (1ULL << (BITS_PER_LONG_LONG - 3))
  19#define PFN_MAP (1ULL << (BITS_PER_LONG_LONG - 4))
  20#define PFN_SPECIAL (1ULL << (BITS_PER_LONG_LONG - 5))
  21
  22#define PFN_FLAGS_TRACE \
  23        { PFN_SPECIAL,  "SPECIAL" }, \
  24        { PFN_SG_CHAIN, "SG_CHAIN" }, \
  25        { PFN_SG_LAST,  "SG_LAST" }, \
  26        { PFN_DEV,      "DEV" }, \
  27        { PFN_MAP,      "MAP" }
  28
  29static inline pfn_t __pfn_to_pfn_t(unsigned long pfn, u64 flags)
  30{
  31        pfn_t pfn_t = { .val = pfn | (flags & PFN_FLAGS_MASK), };
  32
  33        return pfn_t;
  34}
  35
  36/* a default pfn to pfn_t conversion assumes that @pfn is pfn_valid() */
  37static inline pfn_t pfn_to_pfn_t(unsigned long pfn)
  38{
  39        return __pfn_to_pfn_t(pfn, 0);
  40}
  41
  42static inline pfn_t phys_to_pfn_t(phys_addr_t addr, u64 flags)
  43{
  44        return __pfn_to_pfn_t(addr >> PAGE_SHIFT, flags);
  45}
  46
  47static inline bool pfn_t_has_page(pfn_t pfn)
  48{
  49        return (pfn.val & PFN_MAP) == PFN_MAP || (pfn.val & PFN_DEV) == 0;
  50}
  51
  52static inline unsigned long pfn_t_to_pfn(pfn_t pfn)
  53{
  54        return pfn.val & ~PFN_FLAGS_MASK;
  55}
  56
  57static inline struct page *pfn_t_to_page(pfn_t pfn)
  58{
  59        if (pfn_t_has_page(pfn))
  60                return pfn_to_page(pfn_t_to_pfn(pfn));
  61        return NULL;
  62}
  63
  64static inline phys_addr_t pfn_t_to_phys(pfn_t pfn)
  65{
  66        return PFN_PHYS(pfn_t_to_pfn(pfn));
  67}
  68
  69static inline void *pfn_t_to_virt(pfn_t pfn)
  70{
  71        if (pfn_t_has_page(pfn) && !is_device_private_page(pfn_t_to_page(pfn)))
  72                return __va(pfn_t_to_phys(pfn));
  73        return NULL;
  74}
  75
  76static inline pfn_t page_to_pfn_t(struct page *page)
  77{
  78        return pfn_to_pfn_t(page_to_pfn(page));
  79}
  80
  81static inline int pfn_t_valid(pfn_t pfn)
  82{
  83        return pfn_valid(pfn_t_to_pfn(pfn));
  84}
  85
  86#ifdef CONFIG_MMU
  87static inline pte_t pfn_t_pte(pfn_t pfn, pgprot_t pgprot)
  88{
  89        return pfn_pte(pfn_t_to_pfn(pfn), pgprot);
  90}
  91#endif
  92
  93#ifdef CONFIG_TRANSPARENT_HUGEPAGE
  94static inline pmd_t pfn_t_pmd(pfn_t pfn, pgprot_t pgprot)
  95{
  96        return pfn_pmd(pfn_t_to_pfn(pfn), pgprot);
  97}
  98
  99#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
 100static inline pud_t pfn_t_pud(pfn_t pfn, pgprot_t pgprot)
 101{
 102        return pfn_pud(pfn_t_to_pfn(pfn), pgprot);
 103}
 104#endif
 105#endif
 106
 107#ifdef __HAVE_ARCH_PTE_DEVMAP
 108static inline bool pfn_t_devmap(pfn_t pfn)
 109{
 110        const u64 flags = PFN_DEV|PFN_MAP;
 111
 112        return (pfn.val & flags) == flags;
 113}
 114#else
 115static inline bool pfn_t_devmap(pfn_t pfn)
 116{
 117        return false;
 118}
 119pte_t pte_mkdevmap(pte_t pte);
 120pmd_t pmd_mkdevmap(pmd_t pmd);
 121#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && \
 122        defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)
 123pud_t pud_mkdevmap(pud_t pud);
 124#endif
 125#endif /* __HAVE_ARCH_PTE_DEVMAP */
 126
 127#ifdef CONFIG_ARCH_HAS_PTE_SPECIAL
 128static inline bool pfn_t_special(pfn_t pfn)
 129{
 130        return (pfn.val & PFN_SPECIAL) == PFN_SPECIAL;
 131}
 132#else
 133static inline bool pfn_t_special(pfn_t pfn)
 134{
 135        return false;
 136}
 137#endif /* CONFIG_ARCH_HAS_PTE_SPECIAL */
 138#endif /* _LINUX_PFN_T_H_ */
 139