1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
|
#ifndef _ASM_X86_CACHEFLUSH_H
#define _ASM_X86_CACHEFLUSH_H
/* Caches aren't brain-dead on the intel. */
#include <asm-generic/cacheflush.h>
#include <asm/special_insns.h>
#include <asm/uaccess.h>
/*
* The set_memory_* API can be used to change various attributes of a virtual
* address range. The attributes include:
* Cachability : UnCached, WriteCombining, WriteThrough, WriteBack
* Executability : eXeutable, NoteXecutable
* Read/Write : ReadOnly, ReadWrite
* Presence : NotPresent
*
* Within a category, the attributes are mutually exclusive.
*
* The implementation of this API will take care of various aspects that
* are associated with changing such attributes, such as:
* - Flushing TLBs
* - Flushing CPU caches
* - Making sure aliases of the memory behind the mapping don't violate
* coherency rules as defined by the CPU in the system.
*
* What this API does not do:
* - Provide exclusion between various callers - including callers that
* operation on other mappings of the same physical page
* - Restore default attributes when a page is freed
* - Guarantee that mappings other than the requested one are
* in any state, other than that these do not violate rules for
* the CPU you have. Do not depend on any effects on other mappings,
* CPUs other than the one you have may have more relaxed rules.
* The caller is required to take care of these.
*/
int _set_memory_uc(unsigned long addr, int numpages);
int _set_memory_wc(unsigned long addr, int numpages);
int _set_memory_wt(unsigned long addr, int numpages);
int _set_memory_wb(unsigned long addr, int numpages);
int set_memory_uc(unsigned long addr, int numpages);
int set_memory_wc(unsigned long addr, int numpages);
int set_memory_wt(unsigned long addr, int numpages);
int set_memory_wb(unsigned long addr, int numpages);
int set_memory_x(unsigned long addr, int numpages);
int set_memory_nx(unsigned long addr, int numpages);
int set_memory_ro(unsigned long addr, int numpages);
int set_memory_rw(unsigned long addr, int numpages);
int set_memory_np(unsigned long addr, int numpages);
int set_memory_4k(unsigned long addr, int numpages);
int set_memory_array_uc(unsigned long *addr, int addrinarray);
int set_memory_array_wc(unsigned long *addr, int addrinarray);
int set_memory_array_wt(unsigned long *addr, int addrinarray);
int set_memory_array_wb(unsigned long *addr, int addrinarray);
int set_pages_array_uc(struct page **pages, int addrinarray);
int set_pages_array_wc(struct page **pages, int addrinarray);
int set_pages_array_wt(struct page **pages, int addrinarray);
int set_pages_array_wb(struct page **pages, int addrinarray);
/*
* For legacy compatibility with the old APIs, a few functions
* are provided that work on a "struct page".
* These functions operate ONLY on the 1:1 kernel mapping of the
* memory that the struct page represents, and internally just
* call the set_memory_* function. See the description of the
* set_memory_* function for more details on conventions.
*
* These APIs should be considered *deprecated* and are likely going to
* be removed in the future.
* The reason for this is the implicit operation on the 1:1 mapping only,
* making this not a generally useful API.
*
* Specifically, many users of the old APIs had a virtual address,
* called virt_to_page() or vmalloc_to_page() on that address to
* get a struct page* that the old API required.
* To convert these cases, use set_memory_*() on the original
* virtual address, do not use these functions.
*/
int set_pages_uc(struct page *page, int numpages);
int set_pages_wb(struct page *page, int numpages);
int set_pages_x(struct page *page, int numpages);
int set_pages_nx(struct page *page, int numpages);
int set_pages_ro(struct page *page, int numpages);
int set_pages_rw(struct page *page, int numpages);
void clflush_cache_range(void *addr, unsigned int size);
#ifdef CONFIG_DEBUG_RODATA
void mark_rodata_ro(void);
extern const int rodata_test_data;
extern int kernel_set_to_readonly;
void set_kernel_text_rw(void);
void set_kernel_text_ro(void);
#else
static inline void set_kernel_text_rw(void) { }
static inline void set_kernel_text_ro(void) { }
#endif
#ifdef CONFIG_DEBUG_RODATA_TEST
int rodata_test(void);
#else
static inline int rodata_test(void)
{
return 0;
}
#endif
#ifdef ARCH_HAS_NOCACHE_UACCESS
/**
* arch_memcpy_to_pmem - copy data to persistent memory
* @dst: destination buffer for the copy
* @src: source buffer for the copy
* @n: length of the copy in bytes
*
* Copy data to persistent memory media via non-temporal stores so that
* a subsequent arch_wmb_pmem() can flush cpu and memory controller
* write buffers to guarantee durability.
*/
static inline void arch_memcpy_to_pmem(void __pmem *dst, const void *src,
size_t n)
{
int unwritten;
/*
* We are copying between two kernel buffers, if
* __copy_from_user_inatomic_nocache() returns an error (page
* fault) we would have already reported a general protection fault
* before the WARN+BUG.
*/
unwritten = __copy_from_user_inatomic_nocache((void __force *) dst,
(void __user *) src, n);
if (WARN(unwritten, "%s: fault copying %p <- %p unwritten: %d\n",
__func__, dst, src, unwritten))
BUG();
}
/**
* arch_wmb_pmem - synchronize writes to persistent memory
*
* After a series of arch_memcpy_to_pmem() operations this drains data
* from cpu write buffers and any platform (memory controller) buffers
* to ensure that written data is durable on persistent memory media.
*/
static inline void arch_wmb_pmem(void)
{
/*
* wmb() to 'sfence' all previous writes such that they are
* architecturally visible to 'pcommit'. Note, that we've
* already arranged for pmem writes to avoid the cache via
* arch_memcpy_to_pmem().
*/
wmb();
pcommit_sfence();
}
static inline bool __arch_has_wmb_pmem(void)
{
#ifdef CONFIG_X86_64
/*
* We require that wmb() be an 'sfence', that is only guaranteed on
* 64-bit builds
*/
return static_cpu_has(X86_FEATURE_PCOMMIT);
#else
return false;
#endif
}
#else /* ARCH_HAS_NOCACHE_UACCESS i.e. ARCH=um */
extern void arch_memcpy_to_pmem(void __pmem *dst, const void *src, size_t n);
extern void arch_wmb_pmem(void);
static inline bool __arch_has_wmb_pmem(void)
{
return false;
}
#endif
#endif /* _ASM_X86_CACHEFLUSH_H */
|
