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 * x86_32 and x86_64 integration by Gustavo F. Padovan, February 2009
12 */
13
14 #ifndef _ASM_X86_FIXMAP_H
15 #define _ASM_X86_FIXMAP_H
16
17 #ifndef __ASSEMBLY__
18 #include <linux/kernel.h>
19 #include <asm/acpi.h>
20 #include <asm/apicdef.h>
21 #include <asm/page.h>
22 #include <asm/pvclock.h>
23 #ifdef CONFIG_X86_32
24 #include <linux/threads.h>
25 #include <asm/kmap_types.h>
26 #else
27 #include <uapi/asm/vsyscall.h>
28 #endif
29
30 /*
31 * We can't declare FIXADDR_TOP as variable for x86_64 because vsyscall
32 * uses fixmaps that relies on FIXADDR_TOP for proper address calculation.
33 * Because of this, FIXADDR_TOP x86 integration was left as later work.
34 */
35 #ifdef CONFIG_X86_32
36 /* used by vmalloc.c, vsyscall.lds.S.
37 *
38 * Leave one empty page between vmalloc'ed areas and
39 * the start of the fixmap.
40 */
41 extern unsigned long __FIXADDR_TOP;
42 #define FIXADDR_TOP ((unsigned long)__FIXADDR_TOP)
43 #else
44 #define FIXADDR_TOP (round_up(VSYSCALL_ADDR + PAGE_SIZE, 1<<PMD_SHIFT) - \
45 PAGE_SIZE)
46 #endif
47
48
49 /*
50 * Here we define all the compile-time 'special' virtual
51 * addresses. The point is to have a constant address at
52 * compile time, but to set the physical address only
53 * in the boot process.
54 * for x86_32: We allocate these special addresses
55 * from the end of virtual memory (0xfffff000) backwards.
56 * Also this lets us do fail-safe vmalloc(), we
57 * can guarantee that these special addresses and
58 * vmalloc()-ed addresses never overlap.
59 *
60 * These 'compile-time allocated' memory buffers are
61 * fixed-size 4k pages (or larger if used with an increment
62 * higher than 1). Use set_fixmap(idx,phys) to associate
63 * physical memory with fixmap indices.
64 *
65 * TLB entries of such buffers will not be flushed across
66 * task switches.
67 */
68 enum fixed_addresses {
69 #ifdef CONFIG_X86_32
70 FIX_HOLE,
71 #else
72 #ifdef CONFIG_X86_VSYSCALL_EMULATION
73 VSYSCALL_PAGE = (FIXADDR_TOP - VSYSCALL_ADDR) >> PAGE_SHIFT,
74 #endif
75 #ifdef CONFIG_PARAVIRT_CLOCK
76 PVCLOCK_FIXMAP_BEGIN,
77 PVCLOCK_FIXMAP_END = PVCLOCK_FIXMAP_BEGIN+PVCLOCK_VSYSCALL_NR_PAGES-1,
78 #endif
79 #endif
80 FIX_DBGP_BASE,
81 FIX_EARLYCON_MEM_BASE,
82 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
83 FIX_OHCI1394_BASE,
84 #endif
85 #ifdef CONFIG_X86_LOCAL_APIC
86 FIX_APIC_BASE, /* local (CPU) APIC) -- required for SMP or not */
87 #endif
88 #ifdef CONFIG_X86_IO_APIC
89 FIX_IO_APIC_BASE_0,
90 FIX_IO_APIC_BASE_END = FIX_IO_APIC_BASE_0 + MAX_IO_APICS - 1,
91 #endif
92 FIX_RO_IDT, /* Virtual mapping for read-only IDT */
93 #ifdef CONFIG_X86_32
94 FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
95 FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
96 #ifdef CONFIG_PCI_MMCONFIG
97 FIX_PCIE_MCFG,
98 #endif
99 #endif
100 #ifdef CONFIG_PARAVIRT
101 FIX_PARAVIRT_BOOTMAP,
102 #endif
103 FIX_TEXT_POKE1, /* reserve 2 pages for text_poke() */
104 FIX_TEXT_POKE0, /* first page is last, because allocation is backward */
105 #ifdef CONFIG_X86_INTEL_MID
106 FIX_LNW_VRTC,
107 #endif
108 __end_of_permanent_fixed_addresses,
109
110 /*
111 * 512 temporary boot-time mappings, used by early_ioremap(),
112 * before ioremap() is functional.
113 *
114 * If necessary we round it up to the next 512 pages boundary so
115 * that we can have a single pgd entry and a single pte table:
116 */
117 #define NR_FIX_BTMAPS 64
118 #define FIX_BTMAPS_SLOTS 8
119 #define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
120 FIX_BTMAP_END =
121 (__end_of_permanent_fixed_addresses ^
122 (__end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS - 1)) &
123 -PTRS_PER_PTE
124 ? __end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS -
125 (__end_of_permanent_fixed_addresses & (TOTAL_FIX_BTMAPS - 1))
126 : __end_of_permanent_fixed_addresses,
127 FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
128 #ifdef CONFIG_X86_32
129 FIX_WP_TEST,
130 #endif
131 #ifdef CONFIG_INTEL_TXT
132 FIX_TBOOT_BASE,
133 #endif
134 __end_of_fixed_addresses
135 };
136
137
138 extern void reserve_top_address(unsigned long reserve);
139
140 #define FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT)
141 #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE)
142
143 extern int fixmaps_set;
144
145 extern pte_t *kmap_pte;
146 extern pgprot_t kmap_prot;
147 extern pte_t *pkmap_page_table;
148
149 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
150 void native_set_fixmap(unsigned /* enum fixed_addresses */ idx,
151 phys_addr_t phys, pgprot_t flags);
152
153 #ifndef CONFIG_PARAVIRT
__set_fixmap(enum fixed_addresses idx,phys_addr_t phys,pgprot_t flags)154 static inline void __set_fixmap(enum fixed_addresses idx,
155 phys_addr_t phys, pgprot_t flags)
156 {
157 native_set_fixmap(idx, phys, flags);
158 }
159 #endif
160
161 #include <asm-generic/fixmap.h>
162
163 #define __late_set_fixmap(idx, phys, flags) __set_fixmap(idx, phys, flags)
164 #define __late_clear_fixmap(idx) __set_fixmap(idx, 0, __pgprot(0))
165
166 void __early_set_fixmap(enum fixed_addresses idx,
167 phys_addr_t phys, pgprot_t flags);
168
169 #endif /* !__ASSEMBLY__ */
170 #endif /* _ASM_X86_FIXMAP_H */
171