1 #ifndef _ASM_X86_FIXMAP_H
2 #define _ASM_X86_FIXMAP_H
3
4 #ifdef CONFIG_X86_32
5 # include "fixmap_32.h"
6 #else
7 # include "fixmap_64.h"
8 #endif
9
10 extern int fixmaps_set;
11
12 extern pte_t *kmap_pte;
13 extern pgprot_t kmap_prot;
14 extern pte_t *pkmap_page_table;
15
16 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
17 void native_set_fixmap(enum fixed_addresses idx,
18 unsigned long phys, pgprot_t flags);
19
20 #ifndef CONFIG_PARAVIRT
__set_fixmap(enum fixed_addresses idx,unsigned long phys,pgprot_t flags)21 static inline void __set_fixmap(enum fixed_addresses idx,
22 unsigned long phys, pgprot_t flags)
23 {
24 native_set_fixmap(idx, phys, flags);
25 }
26 #endif
27
28 #define set_fixmap(idx, phys) \
29 __set_fixmap(idx, phys, PAGE_KERNEL)
30
31 /*
32 * Some hardware wants to get fixmapped without caching.
33 */
34 #define set_fixmap_nocache(idx, phys) \
35 __set_fixmap(idx, phys, PAGE_KERNEL_NOCACHE)
36
37 #define clear_fixmap(idx) \
38 __set_fixmap(idx, 0, __pgprot(0))
39
40 #define __fix_to_virt(x) (FIXADDR_TOP - ((x) << PAGE_SHIFT))
41 #define __virt_to_fix(x) ((FIXADDR_TOP - ((x)&PAGE_MASK)) >> PAGE_SHIFT)
42
43 extern void __this_fixmap_does_not_exist(void);
44
45 /*
46 * 'index to address' translation. If anyone tries to use the idx
47 * directly without translation, we catch the bug with a NULL-deference
48 * kernel oops. Illegal ranges of incoming indices are caught too.
49 */
fix_to_virt(const unsigned int idx)50 static __always_inline unsigned long fix_to_virt(const unsigned int idx)
51 {
52 /*
53 * this branch gets completely eliminated after inlining,
54 * except when someone tries to use fixaddr indices in an
55 * illegal way. (such as mixing up address types or using
56 * out-of-range indices).
57 *
58 * If it doesn't get removed, the linker will complain
59 * loudly with a reasonably clear error message..
60 */
61 if (idx >= __end_of_fixed_addresses)
62 __this_fixmap_does_not_exist();
63
64 return __fix_to_virt(idx);
65 }
66
virt_to_fix(const unsigned long vaddr)67 static inline unsigned long virt_to_fix(const unsigned long vaddr)
68 {
69 BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START);
70 return __virt_to_fix(vaddr);
71 }
72 #endif /* _ASM_X86_FIXMAP_H */
73