xref: /openbmc/linux/arch/x86/include/asm/set_memory.h (revision 6aa7de05)
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  * Encryption    : Encrypted, Decrypted
15  *
16  * Within a category, the attributes are mutually exclusive.
17  *
18  * The implementation of this API will take care of various aspects that
19  * are associated with changing such attributes, such as:
20  * - Flushing TLBs
21  * - Flushing CPU caches
22  * - Making sure aliases of the memory behind the mapping don't violate
23  *   coherency rules as defined by the CPU in the system.
24  *
25  * What this API does not do:
26  * - Provide exclusion between various callers - including callers that
27  *   operation on other mappings of the same physical page
28  * - Restore default attributes when a page is freed
29  * - Guarantee that mappings other than the requested one are
30  *   in any state, other than that these do not violate rules for
31  *   the CPU you have. Do not depend on any effects on other mappings,
32  *   CPUs other than the one you have may have more relaxed rules.
33  * The caller is required to take care of these.
34  */
35 
36 int _set_memory_uc(unsigned long addr, int numpages);
37 int _set_memory_wc(unsigned long addr, int numpages);
38 int _set_memory_wt(unsigned long addr, int numpages);
39 int _set_memory_wb(unsigned long addr, int numpages);
40 int set_memory_uc(unsigned long addr, int numpages);
41 int set_memory_wc(unsigned long addr, int numpages);
42 int set_memory_wt(unsigned long addr, int numpages);
43 int set_memory_wb(unsigned long addr, int numpages);
44 int set_memory_np(unsigned long addr, int numpages);
45 int set_memory_4k(unsigned long addr, int numpages);
46 int set_memory_encrypted(unsigned long addr, int numpages);
47 int set_memory_decrypted(unsigned long addr, int numpages);
48 
49 int set_memory_array_uc(unsigned long *addr, int addrinarray);
50 int set_memory_array_wc(unsigned long *addr, int addrinarray);
51 int set_memory_array_wt(unsigned long *addr, int addrinarray);
52 int set_memory_array_wb(unsigned long *addr, int addrinarray);
53 
54 int set_pages_array_uc(struct page **pages, int addrinarray);
55 int set_pages_array_wc(struct page **pages, int addrinarray);
56 int set_pages_array_wt(struct page **pages, int addrinarray);
57 int set_pages_array_wb(struct page **pages, int addrinarray);
58 
59 /*
60  * For legacy compatibility with the old APIs, a few functions
61  * are provided that work on a "struct page".
62  * These functions operate ONLY on the 1:1 kernel mapping of the
63  * memory that the struct page represents, and internally just
64  * call the set_memory_* function. See the description of the
65  * set_memory_* function for more details on conventions.
66  *
67  * These APIs should be considered *deprecated* and are likely going to
68  * be removed in the future.
69  * The reason for this is the implicit operation on the 1:1 mapping only,
70  * making this not a generally useful API.
71  *
72  * Specifically, many users of the old APIs had a virtual address,
73  * called virt_to_page() or vmalloc_to_page() on that address to
74  * get a struct page* that the old API required.
75  * To convert these cases, use set_memory_*() on the original
76  * virtual address, do not use these functions.
77  */
78 
79 int set_pages_uc(struct page *page, int numpages);
80 int set_pages_wb(struct page *page, int numpages);
81 int set_pages_x(struct page *page, int numpages);
82 int set_pages_nx(struct page *page, int numpages);
83 int set_pages_ro(struct page *page, int numpages);
84 int set_pages_rw(struct page *page, int numpages);
85 
86 extern int kernel_set_to_readonly;
87 void set_kernel_text_rw(void);
88 void set_kernel_text_ro(void);
89 
90 #endif /* _ASM_X86_SET_MEMORY_H */
91