tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#ifndef _LINUX_PFN_T_H_
2#define _LINUX_PFN_T_H_
3#include <linux/mm.h>
4
5/*
6 * PFN_FLAGS_MASK - mask of all the possible valid pfn_t flags
7 * PFN_SG_CHAIN - pfn is a pointer to the next scatterlist entry
8 * PFN_SG_LAST - pfn references a page and is the last scatterlist entry
9 * PFN_DEV - pfn is not covered by system memmap by default
10 * PFN_MAP - pfn has a dynamic page mapping established by a device driver
11 */
12#define PFN_FLAGS_MASK (((unsigned long) ~PAGE_MASK) \
13 << (BITS_PER_LONG - PAGE_SHIFT))
14#define PFN_SG_CHAIN (1UL << (BITS_PER_LONG - 1))
15#define PFN_SG_LAST (1UL << (BITS_PER_LONG - 2))
16#define PFN_DEV (1UL << (BITS_PER_LONG - 3))
17#define PFN_MAP (1UL << (BITS_PER_LONG - 4))
18
19static inline pfn_t __pfn_to_pfn_t(unsigned long pfn, unsigned long flags)
20{
21 pfn_t pfn_t = { .val = pfn | (flags & PFN_FLAGS_MASK), };
22
23 return pfn_t;
24}
25
26/* a default pfn to pfn_t conversion assumes that @pfn is pfn_valid() */
27static inline pfn_t pfn_to_pfn_t(unsigned long pfn)
28{
29 return __pfn_to_pfn_t(pfn, 0);
30}
31
32extern pfn_t phys_to_pfn_t(dma_addr_t addr, unsigned long flags);
33
34static inline bool pfn_t_has_page(pfn_t pfn)
35{
36 return (pfn.val & PFN_MAP) == PFN_MAP || (pfn.val & PFN_DEV) == 0;
37}
38
39static inline unsigned long pfn_t_to_pfn(pfn_t pfn)
40{
41 return pfn.val & ~PFN_FLAGS_MASK;
42}
43
44static inline struct page *pfn_t_to_page(pfn_t pfn)
45{
46 if (pfn_t_has_page(pfn))
47 return pfn_to_page(pfn_t_to_pfn(pfn));
48 return NULL;
49}
50
51static inline dma_addr_t pfn_t_to_phys(pfn_t pfn)
52{
53 return PFN_PHYS(pfn_t_to_pfn(pfn));
54}
55
56static inline void *pfn_t_to_virt(pfn_t pfn)
57{
58 if (pfn_t_has_page(pfn))
59 return __va(pfn_t_to_phys(pfn));
60 return NULL;
61}
62
63static inline pfn_t page_to_pfn_t(struct page *page)
64{
65 return pfn_to_pfn_t(page_to_pfn(page));
66}
67
68static inline int pfn_t_valid(pfn_t pfn)
69{
70 return pfn_valid(pfn_t_to_pfn(pfn));
71}
72
73#ifdef CONFIG_MMU
74static inline pte_t pfn_t_pte(pfn_t pfn, pgprot_t pgprot)
75{
76 return pfn_pte(pfn_t_to_pfn(pfn), pgprot);
77}
78#endif
79
80#ifdef CONFIG_TRANSPARENT_HUGEPAGE
81static inline pmd_t pfn_t_pmd(pfn_t pfn, pgprot_t pgprot)
82{
83 return pfn_pmd(pfn_t_to_pfn(pfn), pgprot);
84}
85#endif
86
87#ifdef __HAVE_ARCH_PTE_DEVMAP
88static inline bool pfn_t_devmap(pfn_t pfn)
89{
90 const unsigned long flags = PFN_DEV|PFN_MAP;
91
92 return (pfn.val & flags) == flags;
93}
94#else
95static inline bool pfn_t_devmap(pfn_t pfn)
96{
97 return false;
98}
99pte_t pte_mkdevmap(pte_t pte);
100pmd_t pmd_mkdevmap(pmd_t pmd);
101#endif
102#endif /* _LINUX_PFN_T_H_ */