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1#ifndef _ASM_X86_SET_MEMORY_H
2#define _ASM_X86_SET_MEMORY_H
3
4#include <asm/page.h>
5#include <asm-generic/set_memory.h>
6
7/*
8 * The set_memory_* API can be used to change various attributes of a virtual
9 * address range. The attributes include:
10 * Cachability : UnCached, WriteCombining, WriteThrough, WriteBack
11 * Executability : eXeutable, NoteXecutable
12 * Read/Write : ReadOnly, ReadWrite
13 * Presence : NotPresent
14 *
15 * Within a category, the attributes are mutually exclusive.
16 *
17 * The implementation of this API will take care of various aspects that
18 * are associated with changing such attributes, such as:
19 * - Flushing TLBs
20 * - Flushing CPU caches
21 * - Making sure aliases of the memory behind the mapping don't violate
22 * coherency rules as defined by the CPU in the system.
23 *
24 * What this API does not do:
25 * - Provide exclusion between various callers - including callers that
26 * operation on other mappings of the same physical page
27 * - Restore default attributes when a page is freed
28 * - Guarantee that mappings other than the requested one are
29 * in any state, other than that these do not violate rules for
30 * the CPU you have. Do not depend on any effects on other mappings,
31 * CPUs other than the one you have may have more relaxed rules.
32 * The caller is required to take care of these.
33 */
34
35int _set_memory_uc(unsigned long addr, int numpages);
36int _set_memory_wc(unsigned long addr, int numpages);
37int _set_memory_wt(unsigned long addr, int numpages);
38int _set_memory_wb(unsigned long addr, int numpages);
39int set_memory_uc(unsigned long addr, int numpages);
40int set_memory_wc(unsigned long addr, int numpages);
41int set_memory_wt(unsigned long addr, int numpages);
42int set_memory_wb(unsigned long addr, int numpages);
43int set_memory_np(unsigned long addr, int numpages);
44int set_memory_4k(unsigned long addr, int numpages);
45
46int set_memory_array_uc(unsigned long *addr, int addrinarray);
47int set_memory_array_wc(unsigned long *addr, int addrinarray);
48int set_memory_array_wt(unsigned long *addr, int addrinarray);
49int set_memory_array_wb(unsigned long *addr, int addrinarray);
50
51int set_pages_array_uc(struct page **pages, int addrinarray);
52int set_pages_array_wc(struct page **pages, int addrinarray);
53int set_pages_array_wt(struct page **pages, int addrinarray);
54int set_pages_array_wb(struct page **pages, int addrinarray);
55
56/*
57 * For legacy compatibility with the old APIs, a few functions
58 * are provided that work on a "struct page".
59 * These functions operate ONLY on the 1:1 kernel mapping of the
60 * memory that the struct page represents, and internally just
61 * call the set_memory_* function. See the description of the
62 * set_memory_* function for more details on conventions.
63 *
64 * These APIs should be considered *deprecated* and are likely going to
65 * be removed in the future.
66 * The reason for this is the implicit operation on the 1:1 mapping only,
67 * making this not a generally useful API.
68 *
69 * Specifically, many users of the old APIs had a virtual address,
70 * called virt_to_page() or vmalloc_to_page() on that address to
71 * get a struct page* that the old API required.
72 * To convert these cases, use set_memory_*() on the original
73 * virtual address, do not use these functions.
74 */
75
76int set_pages_uc(struct page *page, int numpages);
77int set_pages_wb(struct page *page, int numpages);
78int set_pages_x(struct page *page, int numpages);
79int set_pages_nx(struct page *page, int numpages);
80int set_pages_ro(struct page *page, int numpages);
81int set_pages_rw(struct page *page, int numpages);
82
83extern int kernel_set_to_readonly;
84void set_kernel_text_rw(void);
85void set_kernel_text_ro(void);
86
87#endif /* _ASM_X86_SET_MEMORY_H */