1 | /* |
---|
2 | * fixmap.h: compile-time virtual memory allocation |
---|
3 | * |
---|
4 | * This file is subject to the terms and conditions of the GNU General Public |
---|
5 | * License. See the file "COPYING" in the main directory of this archive |
---|
6 | * for more details. |
---|
7 | * |
---|
8 | * Copyright (C) 1998 Ingo Molnar |
---|
9 | * |
---|
10 | * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999 |
---|
11 | */ |
---|
12 | |
---|
13 | #ifndef _ASM_FIXMAP_H |
---|
14 | #define _ASM_FIXMAP_H |
---|
15 | |
---|
16 | |
---|
17 | /* used by vmalloc.c, vsyscall.lds.S. |
---|
18 | * |
---|
19 | * Leave one empty page between vmalloc'ed areas and |
---|
20 | * the start of the fixmap. |
---|
21 | */ |
---|
22 | extern unsigned long __FIXADDR_TOP; |
---|
23 | |
---|
24 | #ifndef __ASSEMBLY__ |
---|
25 | #include <linux/kernel.h> |
---|
26 | #include <asm/acpi.h> |
---|
27 | #include <asm/apicdef.h> |
---|
28 | #include <asm/page.h> |
---|
29 | #ifdef CONFIG_HIGHMEM |
---|
30 | #include <linux/threads.h> |
---|
31 | #include <asm/kmap_types.h> |
---|
32 | #endif |
---|
33 | |
---|
34 | /* |
---|
35 | * Here we define all the compile-time 'special' virtual |
---|
36 | * addresses. The point is to have a constant address at |
---|
37 | * compile time, but to set the physical address only |
---|
38 | * in the boot process. We allocate these special addresses |
---|
39 | * from the end of virtual memory (0xfffff000) backwards. |
---|
40 | * Also this lets us do fail-safe vmalloc(), we |
---|
41 | * can guarantee that these special addresses and |
---|
42 | * vmalloc()-ed addresses never overlap. |
---|
43 | * |
---|
44 | * these 'compile-time allocated' memory buffers are |
---|
45 | * fixed-size 4k pages. (or larger if used with an increment |
---|
46 | * highger than 1) use fixmap_set(idx,phys) to associate |
---|
47 | * physical memory with fixmap indices. |
---|
48 | * |
---|
49 | * TLB entries of such buffers will not be flushed across |
---|
50 | * task switches. |
---|
51 | */ |
---|
52 | enum fixed_addresses { |
---|
53 | FIX_HOLE, |
---|
54 | FIX_VDSO, |
---|
55 | #ifdef CONFIG_X86_LOCAL_APIC |
---|
56 | FIX_APIC_BASE, /* local (CPU) APIC) -- required for SMP or not */ |
---|
57 | #endif |
---|
58 | #ifdef CONFIG_X86_IO_APIC |
---|
59 | FIX_IO_APIC_BASE_0, |
---|
60 | FIX_IO_APIC_BASE_END = FIX_IO_APIC_BASE_0 + MAX_IO_APICS-1, |
---|
61 | #endif |
---|
62 | #ifdef CONFIG_X86_VISWS_APIC |
---|
63 | FIX_CO_CPU, /* Cobalt timer */ |
---|
64 | FIX_CO_APIC, /* Cobalt APIC Redirection Table */ |
---|
65 | FIX_LI_PCIA, /* Lithium PCI Bridge A */ |
---|
66 | FIX_LI_PCIB, /* Lithium PCI Bridge B */ |
---|
67 | #endif |
---|
68 | #ifdef CONFIG_X86_F00F_BUG |
---|
69 | FIX_F00F_IDT, /* Virtual mapping for IDT */ |
---|
70 | #endif |
---|
71 | #ifdef CONFIG_X86_CYCLONE_TIMER |
---|
72 | FIX_CYCLONE_TIMER, /*cyclone timer register*/ |
---|
73 | #endif |
---|
74 | #ifdef CONFIG_HIGHMEM |
---|
75 | FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */ |
---|
76 | FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1, |
---|
77 | #endif |
---|
78 | #ifdef CONFIG_ACPI |
---|
79 | FIX_ACPI_BEGIN, |
---|
80 | FIX_ACPI_END = FIX_ACPI_BEGIN + FIX_ACPI_PAGES - 1, |
---|
81 | #endif |
---|
82 | #ifdef CONFIG_PCI_MMCONFIG |
---|
83 | FIX_PCIE_MCFG, |
---|
84 | #endif |
---|
85 | FIX_SHARED_INFO, |
---|
86 | #define NR_FIX_ISAMAPS 256 |
---|
87 | FIX_ISAMAP_END, |
---|
88 | FIX_ISAMAP_BEGIN = FIX_ISAMAP_END + NR_FIX_ISAMAPS - 1, |
---|
89 | __end_of_permanent_fixed_addresses, |
---|
90 | /* temporary boot-time mappings, used before ioremap() is functional */ |
---|
91 | #define NR_FIX_BTMAPS 16 |
---|
92 | FIX_BTMAP_END = __end_of_permanent_fixed_addresses, |
---|
93 | FIX_BTMAP_BEGIN = FIX_BTMAP_END + NR_FIX_BTMAPS - 1, |
---|
94 | FIX_WP_TEST, |
---|
95 | __end_of_fixed_addresses |
---|
96 | }; |
---|
97 | |
---|
98 | extern void set_fixaddr_top(unsigned long top); |
---|
99 | |
---|
100 | extern void __set_fixmap(enum fixed_addresses idx, |
---|
101 | maddr_t phys, pgprot_t flags); |
---|
102 | |
---|
103 | #define set_fixmap(idx, phys) \ |
---|
104 | __set_fixmap(idx, phys, PAGE_KERNEL) |
---|
105 | /* |
---|
106 | * Some hardware wants to get fixmapped without caching. |
---|
107 | */ |
---|
108 | #define set_fixmap_nocache(idx, phys) \ |
---|
109 | __set_fixmap(idx, phys, PAGE_KERNEL_NOCACHE) |
---|
110 | |
---|
111 | #define clear_fixmap(idx) \ |
---|
112 | __set_fixmap(idx, 0, __pgprot(0)) |
---|
113 | |
---|
114 | #define FIXADDR_TOP ((unsigned long)__FIXADDR_TOP) |
---|
115 | |
---|
116 | #define __FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT) |
---|
117 | #define __FIXADDR_BOOT_SIZE (__end_of_fixed_addresses << PAGE_SHIFT) |
---|
118 | #define FIXADDR_START (FIXADDR_TOP - __FIXADDR_SIZE) |
---|
119 | #define FIXADDR_BOOT_START (FIXADDR_TOP - __FIXADDR_BOOT_SIZE) |
---|
120 | |
---|
121 | #define __fix_to_virt(x) (FIXADDR_TOP - ((x) << PAGE_SHIFT)) |
---|
122 | #define __virt_to_fix(x) ((FIXADDR_TOP - ((x)&PAGE_MASK)) >> PAGE_SHIFT) |
---|
123 | |
---|
124 | extern void __this_fixmap_does_not_exist(void); |
---|
125 | |
---|
126 | /* |
---|
127 | * 'index to address' translation. If anyone tries to use the idx |
---|
128 | * directly without tranlation, we catch the bug with a NULL-deference |
---|
129 | * kernel oops. Illegal ranges of incoming indices are caught too. |
---|
130 | */ |
---|
131 | static __always_inline unsigned long fix_to_virt(const unsigned int idx) |
---|
132 | { |
---|
133 | /* |
---|
134 | * this branch gets completely eliminated after inlining, |
---|
135 | * except when someone tries to use fixaddr indices in an |
---|
136 | * illegal way. (such as mixing up address types or using |
---|
137 | * out-of-range indices). |
---|
138 | * |
---|
139 | * If it doesn't get removed, the linker will complain |
---|
140 | * loudly with a reasonably clear error message.. |
---|
141 | */ |
---|
142 | if (idx >= __end_of_fixed_addresses) |
---|
143 | __this_fixmap_does_not_exist(); |
---|
144 | |
---|
145 | return __fix_to_virt(idx); |
---|
146 | } |
---|
147 | |
---|
148 | static inline unsigned long virt_to_fix(const unsigned long vaddr) |
---|
149 | { |
---|
150 | BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START); |
---|
151 | return __virt_to_fix(vaddr); |
---|
152 | } |
---|
153 | |
---|
154 | #endif /* !__ASSEMBLY__ */ |
---|
155 | #endif |
---|