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-rw-r--r--arch/x86/include/asm/cacheflush.h69
-rw-r--r--arch/x86/mm/pat.c69
2 files changed, 69 insertions, 69 deletions
diff --git a/arch/x86/include/asm/cacheflush.h b/arch/x86/include/asm/cacheflush.h
index 157644bdf70e..47c8e32f621a 100644
--- a/arch/x86/include/asm/cacheflush.h
+++ b/arch/x86/include/asm/cacheflush.h
@@ -5,75 +5,6 @@
5#include <asm-generic/cacheflush.h> 5#include <asm-generic/cacheflush.h>
6#include <asm/special_insns.h> 6#include <asm/special_insns.h>
7 7
8#ifdef CONFIG_X86_PAT
9/*
10 * X86 PAT uses page flags WC and Uncached together to keep track of
11 * memory type of pages that have backing page struct. X86 PAT supports 3
12 * different memory types, _PAGE_CACHE_MODE_WB, _PAGE_CACHE_MODE_WC and
13 * _PAGE_CACHE_MODE_UC_MINUS and fourth state where page's memory type has not
14 * been changed from its default (value of -1 used to denote this).
15 * Note we do not support _PAGE_CACHE_MODE_UC here.
16 */
17
18#define _PGMT_DEFAULT 0
19#define _PGMT_WC (1UL << PG_arch_1)
20#define _PGMT_UC_MINUS (1UL << PG_uncached)
21#define _PGMT_WB (1UL << PG_uncached | 1UL << PG_arch_1)
22#define _PGMT_MASK (1UL << PG_uncached | 1UL << PG_arch_1)
23#define _PGMT_CLEAR_MASK (~_PGMT_MASK)
24
25static inline enum page_cache_mode get_page_memtype(struct page *pg)
26{
27 unsigned long pg_flags = pg->flags & _PGMT_MASK;
28
29 if (pg_flags == _PGMT_DEFAULT)
30 return -1;
31 else if (pg_flags == _PGMT_WC)
32 return _PAGE_CACHE_MODE_WC;
33 else if (pg_flags == _PGMT_UC_MINUS)
34 return _PAGE_CACHE_MODE_UC_MINUS;
35 else
36 return _PAGE_CACHE_MODE_WB;
37}
38
39static inline void set_page_memtype(struct page *pg,
40 enum page_cache_mode memtype)
41{
42 unsigned long memtype_flags;
43 unsigned long old_flags;
44 unsigned long new_flags;
45
46 switch (memtype) {
47 case _PAGE_CACHE_MODE_WC:
48 memtype_flags = _PGMT_WC;
49 break;
50 case _PAGE_CACHE_MODE_UC_MINUS:
51 memtype_flags = _PGMT_UC_MINUS;
52 break;
53 case _PAGE_CACHE_MODE_WB:
54 memtype_flags = _PGMT_WB;
55 break;
56 default:
57 memtype_flags = _PGMT_DEFAULT;
58 break;
59 }
60
61 do {
62 old_flags = pg->flags;
63 new_flags = (old_flags & _PGMT_CLEAR_MASK) | memtype_flags;
64 } while (cmpxchg(&pg->flags, old_flags, new_flags) != old_flags);
65}
66#else
67static inline enum page_cache_mode get_page_memtype(struct page *pg)
68{
69 return -1;
70}
71static inline void set_page_memtype(struct page *pg,
72 enum page_cache_mode memtype)
73{
74}
75#endif
76
77/* 8/*
78 * The set_memory_* API can be used to change various attributes of a virtual 9 * The set_memory_* API can be used to change various attributes of a virtual
79 * address range. The attributes include: 10 * address range. The attributes include:
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index 4c601276a556..25d2c58489e0 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -67,6 +67,75 @@ __setup("debugpat", pat_debug_setup);
67 67
68static u64 __read_mostly boot_pat_state; 68static u64 __read_mostly boot_pat_state;
69 69
70#ifdef CONFIG_X86_PAT
71/*
72 * X86 PAT uses page flags WC and Uncached together to keep track of
73 * memory type of pages that have backing page struct. X86 PAT supports 3
74 * different memory types, _PAGE_CACHE_MODE_WB, _PAGE_CACHE_MODE_WC and
75 * _PAGE_CACHE_MODE_UC_MINUS and fourth state where page's memory type has not
76 * been changed from its default (value of -1 used to denote this).
77 * Note we do not support _PAGE_CACHE_MODE_UC here.
78 */
79
80#define _PGMT_DEFAULT 0
81#define _PGMT_WC (1UL << PG_arch_1)
82#define _PGMT_UC_MINUS (1UL << PG_uncached)
83#define _PGMT_WB (1UL << PG_uncached | 1UL << PG_arch_1)
84#define _PGMT_MASK (1UL << PG_uncached | 1UL << PG_arch_1)
85#define _PGMT_CLEAR_MASK (~_PGMT_MASK)
86
87static inline enum page_cache_mode get_page_memtype(struct page *pg)
88{
89 unsigned long pg_flags = pg->flags & _PGMT_MASK;
90
91 if (pg_flags == _PGMT_DEFAULT)
92 return -1;
93 else if (pg_flags == _PGMT_WC)
94 return _PAGE_CACHE_MODE_WC;
95 else if (pg_flags == _PGMT_UC_MINUS)
96 return _PAGE_CACHE_MODE_UC_MINUS;
97 else
98 return _PAGE_CACHE_MODE_WB;
99}
100
101static inline void set_page_memtype(struct page *pg,
102 enum page_cache_mode memtype)
103{
104 unsigned long memtype_flags;
105 unsigned long old_flags;
106 unsigned long new_flags;
107
108 switch (memtype) {
109 case _PAGE_CACHE_MODE_WC:
110 memtype_flags = _PGMT_WC;
111 break;
112 case _PAGE_CACHE_MODE_UC_MINUS:
113 memtype_flags = _PGMT_UC_MINUS;
114 break;
115 case _PAGE_CACHE_MODE_WB:
116 memtype_flags = _PGMT_WB;
117 break;
118 default:
119 memtype_flags = _PGMT_DEFAULT;
120 break;
121 }
122
123 do {
124 old_flags = pg->flags;
125 new_flags = (old_flags & _PGMT_CLEAR_MASK) | memtype_flags;
126 } while (cmpxchg(&pg->flags, old_flags, new_flags) != old_flags);
127}
128#else
129static inline enum page_cache_mode get_page_memtype(struct page *pg)
130{
131 return -1;
132}
133static inline void set_page_memtype(struct page *pg,
134 enum page_cache_mode memtype)
135{
136}
137#endif
138
70enum { 139enum {
71 PAT_UC = 0, /* uncached */ 140 PAT_UC = 0, /* uncached */
72 PAT_WC = 1, /* Write combining */ 141 PAT_WC = 1, /* Write combining */
generated by cgit v1.2.2 (git 2.25.0) at 2025-04-15 17:33:25 -0400