Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1#ifndef _ASM_FIXMAP_H
2#define _ASM_FIXMAP_H
3
4#ifdef CONFIG_X86_32
5# include "fixmap_32.h"
6#else
7# include "fixmap_64.h"
8#endif
9
10extern int fixmaps_set;
11
12void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
13void native_set_fixmap(enum fixed_addresses idx,
14 unsigned long phys, pgprot_t flags);
15
16#ifndef CONFIG_PARAVIRT
17static inline void __set_fixmap(enum fixed_addresses idx,
18 unsigned long phys, pgprot_t flags)
19{
20 native_set_fixmap(idx, phys, flags);
21}
22#endif
23
24#define set_fixmap(idx, phys) \
25 __set_fixmap(idx, phys, PAGE_KERNEL)
26
27/*
28 * Some hardware wants to get fixmapped without caching.
29 */
30#define set_fixmap_nocache(idx, phys) \
31 __set_fixmap(idx, phys, PAGE_KERNEL_NOCACHE)
32
33#define clear_fixmap(idx) \
34 __set_fixmap(idx, 0, __pgprot(0))
35
36#define __fix_to_virt(x) (FIXADDR_TOP - ((x) << PAGE_SHIFT))
37#define __virt_to_fix(x) ((FIXADDR_TOP - ((x)&PAGE_MASK)) >> PAGE_SHIFT)
38
39extern void __this_fixmap_does_not_exist(void);
40
41/*
42 * 'index to address' translation. If anyone tries to use the idx
43 * directly without translation, we catch the bug with a NULL-deference
44 * kernel oops. Illegal ranges of incoming indices are caught too.
45 */
46static __always_inline unsigned long fix_to_virt(const unsigned int idx)
47{
48 /*
49 * this branch gets completely eliminated after inlining,
50 * except when someone tries to use fixaddr indices in an
51 * illegal way. (such as mixing up address types or using
52 * out-of-range indices).
53 *
54 * If it doesn't get removed, the linker will complain
55 * loudly with a reasonably clear error message..
56 */
57 if (idx >= __end_of_fixed_addresses)
58 __this_fixmap_does_not_exist();
59
60 return __fix_to_virt(idx);
61}
62
63static inline unsigned long virt_to_fix(const unsigned long vaddr)
64{
65 BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START);
66 return __virt_to_fix(vaddr);
67}
68#endif