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))
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