tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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#define PFN_SPECIAL (1ULL << (BITS_PER_LONG_LONG - 5))
19
20#define PFN_FLAGS_TRACE \
21 { PFN_SPECIAL, "SPECIAL" }, \
22 { PFN_SG_CHAIN, "SG_CHAIN" }, \
23 { PFN_SG_LAST, "SG_LAST" }, \
24 { PFN_DEV, "DEV" }, \
25 { PFN_MAP, "MAP" }
26
27static inline pfn_t __pfn_to_pfn_t(unsigned long pfn, u64 flags)
28{
29 pfn_t pfn_t = { .val = pfn | (flags & PFN_FLAGS_MASK), };
30
31 return pfn_t;
32}
33
34/* a default pfn to pfn_t conversion assumes that @pfn is pfn_valid() */
35static inline pfn_t pfn_to_pfn_t(unsigned long pfn)
36{
37 return __pfn_to_pfn_t(pfn, 0);
38}
39
40static inline pfn_t phys_to_pfn_t(phys_addr_t addr, u64 flags)
41{
42 return __pfn_to_pfn_t(addr >> PAGE_SHIFT, flags);
43}
44
45static inline bool pfn_t_has_page(pfn_t pfn)
46{
47 return (pfn.val & PFN_MAP) == PFN_MAP || (pfn.val & PFN_DEV) == 0;
48}
49
50static inline unsigned long pfn_t_to_pfn(pfn_t pfn)
51{
52 return pfn.val & ~PFN_FLAGS_MASK;
53}
54
55static inline struct page *pfn_t_to_page(pfn_t pfn)
56{
57 if (pfn_t_has_page(pfn))
58 return pfn_to_page(pfn_t_to_pfn(pfn));
59 return NULL;
60}
61
62static inline phys_addr_t pfn_t_to_phys(pfn_t pfn)
63{
64 return PFN_PHYS(pfn_t_to_pfn(pfn));
65}
66
67static inline void *pfn_t_to_virt(pfn_t pfn)
68{
69 if (pfn_t_has_page(pfn))
70 return __va(pfn_t_to_phys(pfn));
71 return NULL;
72}
73
74static inline pfn_t page_to_pfn_t(struct page *page)
75{
76 return pfn_to_pfn_t(page_to_pfn(page));
77}
78
79static inline int pfn_t_valid(pfn_t pfn)
80{
81 return pfn_valid(pfn_t_to_pfn(pfn));
82}
83
84#ifdef CONFIG_MMU
85static inline pte_t pfn_t_pte(pfn_t pfn, pgprot_t pgprot)
86{
87 return pfn_pte(pfn_t_to_pfn(pfn), pgprot);
88}
89#endif
90
91#ifdef CONFIG_TRANSPARENT_HUGEPAGE
92static inline pmd_t pfn_t_pmd(pfn_t pfn, pgprot_t pgprot)
93{
94 return pfn_pmd(pfn_t_to_pfn(pfn), pgprot);
95}
96
97#ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
98static inline pud_t pfn_t_pud(pfn_t pfn, pgprot_t pgprot)
99{
100 return pfn_pud(pfn_t_to_pfn(pfn), pgprot);
101}
102#endif
103#endif
104
105#ifdef __HAVE_ARCH_PTE_DEVMAP
106static inline bool pfn_t_devmap(pfn_t pfn)
107{
108 const u64 flags = PFN_DEV|PFN_MAP;
109
110 return (pfn.val & flags) == flags;
111}
112#else
113static inline bool pfn_t_devmap(pfn_t pfn)
114{
115 return false;
116}
117pte_t pte_mkdevmap(pte_t pte);
118pmd_t pmd_mkdevmap(pmd_t pmd);
119#if defined(CONFIG_TRANSPARENT_HUGEPAGE) && \
120 defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)
121pud_t pud_mkdevmap(pud_t pud);
122#endif
123#endif /* __HAVE_ARCH_PTE_DEVMAP */
124
125#ifdef CONFIG_ARCH_HAS_PTE_SPECIAL
126static inline bool pfn_t_special(pfn_t pfn)
127{
128 return (pfn.val & PFN_SPECIAL) == PFN_SPECIAL;
129}
130#else
131static inline bool pfn_t_special(pfn_t pfn)
132{
133 return false;
134}
135#endif /* CONFIG_ARCH_HAS_PTE_SPECIAL */
136#endif /* _LINUX_PFN_T_H_ */