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