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 
__pfn_to_pfn_t(unsigned long pfn,u64 flags)29 static 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() */
pfn_to_pfn_t(unsigned long pfn)37 static inline pfn_t pfn_to_pfn_t(unsigned long pfn)
38 {
39 	return __pfn_to_pfn_t(pfn, 0);
40 }
41 
phys_to_pfn_t(phys_addr_t addr,u64 flags)42 static 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 
pfn_t_has_page(pfn_t pfn)47 static 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 
pfn_t_to_pfn(pfn_t pfn)52 static inline unsigned long pfn_t_to_pfn(pfn_t pfn)
53 {
54 	return pfn.val & ~PFN_FLAGS_MASK;
55 }
56 
pfn_t_to_page(pfn_t pfn)57 static 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 
pfn_t_to_phys(pfn_t pfn)64 static inline phys_addr_t pfn_t_to_phys(pfn_t pfn)
65 {
66 	return PFN_PHYS(pfn_t_to_pfn(pfn));
67 }
68 
page_to_pfn_t(struct page * page)69 static inline pfn_t page_to_pfn_t(struct page *page)
70 {
71 	return pfn_to_pfn_t(page_to_pfn(page));
72 }
73 
pfn_t_valid(pfn_t pfn)74 static inline int pfn_t_valid(pfn_t pfn)
75 {
76 	return pfn_valid(pfn_t_to_pfn(pfn));
77 }
78 
79 #ifdef CONFIG_MMU
pfn_t_pte(pfn_t pfn,pgprot_t pgprot)80 static inline pte_t pfn_t_pte(pfn_t pfn, pgprot_t pgprot)
81 {
82 	return pfn_pte(pfn_t_to_pfn(pfn), pgprot);
83 }
84 #endif
85 
86 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
pfn_t_pmd(pfn_t pfn,pgprot_t pgprot)87 static inline pmd_t pfn_t_pmd(pfn_t pfn, pgprot_t pgprot)
88 {
89 	return pfn_pmd(pfn_t_to_pfn(pfn), pgprot);
90 }
91 
92 #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
pfn_t_pud(pfn_t pfn,pgprot_t pgprot)93 static inline pud_t pfn_t_pud(pfn_t pfn, pgprot_t pgprot)
94 {
95 	return pfn_pud(pfn_t_to_pfn(pfn), pgprot);
96 }
97 #endif
98 #endif
99 
100 #ifdef CONFIG_ARCH_HAS_PTE_DEVMAP
pfn_t_devmap(pfn_t pfn)101 static inline bool pfn_t_devmap(pfn_t pfn)
102 {
103 	const u64 flags = PFN_DEV|PFN_MAP;
104 
105 	return (pfn.val & flags) == flags;
106 }
107 #else
pfn_t_devmap(pfn_t pfn)108 static inline bool pfn_t_devmap(pfn_t pfn)
109 {
110 	return false;
111 }
112 pte_t pte_mkdevmap(pte_t pte);
113 pmd_t pmd_mkdevmap(pmd_t pmd);
114 #if defined(CONFIG_TRANSPARENT_HUGEPAGE) && \
115 	defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)
116 pud_t pud_mkdevmap(pud_t pud);
117 #endif
118 #endif /* CONFIG_ARCH_HAS_PTE_DEVMAP */
119 
120 #ifdef CONFIG_ARCH_HAS_PTE_SPECIAL
pfn_t_special(pfn_t pfn)121 static inline bool pfn_t_special(pfn_t pfn)
122 {
123 	return (pfn.val & PFN_SPECIAL) == PFN_SPECIAL;
124 }
125 #else
pfn_t_special(pfn_t pfn)126 static inline bool pfn_t_special(pfn_t pfn)
127 {
128 	return false;
129 }
130 #endif /* CONFIG_ARCH_HAS_PTE_SPECIAL */
131 #endif /* _LINUX_PFN_T_H_ */
132