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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/*
18 * Exposed to assembly code for setting up initial page tables. Cannot be
19 * calculated in assembly code (fixmap entries are an enum), but is sanity
20 * checked in the actual fixmap C code to make sure that the fixmap is
21 * covered fully.
22 */
23#define FIXMAP_PMD_NUM 2
24/* fixmap starts downwards from the 507th entry in level2_fixmap_pgt */
25#define FIXMAP_PMD_TOP 507
26
27#ifndef __ASSEMBLY__
28#include <linux/kernel.h>
29#include <asm/acpi.h>
30#include <asm/apicdef.h>
31#include <asm/page.h>
32#ifdef CONFIG_X86_32
33#include <linux/threads.h>
34#include <asm/kmap_types.h>
35#else
36#include <uapi/asm/vsyscall.h>
37#endif
38
39/*
40 * We can't declare FIXADDR_TOP as variable for x86_64 because vsyscall
41 * uses fixmaps that relies on FIXADDR_TOP for proper address calculation.
42 * Because of this, FIXADDR_TOP x86 integration was left as later work.
43 */
44#ifdef CONFIG_X86_32
45/* used by vmalloc.c, vsyscall.lds.S.
46 *
47 * Leave one empty page between vmalloc'ed areas and
48 * the start of the fixmap.
49 */
50extern unsigned long __FIXADDR_TOP;
51#define FIXADDR_TOP ((unsigned long)__FIXADDR_TOP)
52#else
53#define FIXADDR_TOP (round_up(VSYSCALL_ADDR + PAGE_SIZE, 1<<PMD_SHIFT) - \
54 PAGE_SIZE)
55#endif
56
57/*
58 * Here we define all the compile-time 'special' virtual
59 * addresses. The point is to have a constant address at
60 * compile time, but to set the physical address only
61 * in the boot process.
62 * for x86_32: We allocate these special addresses
63 * from the end of virtual memory (0xfffff000) backwards.
64 * Also this lets us do fail-safe vmalloc(), we
65 * can guarantee that these special addresses and
66 * vmalloc()-ed addresses never overlap.
67 *
68 * These 'compile-time allocated' memory buffers are
69 * fixed-size 4k pages (or larger if used with an increment
70 * higher than 1). Use set_fixmap(idx,phys) to associate
71 * physical memory with fixmap indices.
72 *
73 * TLB entries of such buffers will not be flushed across
74 * task switches.
75 */
76enum fixed_addresses {
77#ifdef CONFIG_X86_32
78 FIX_HOLE,
79#else
80#ifdef CONFIG_X86_VSYSCALL_EMULATION
81 VSYSCALL_PAGE = (FIXADDR_TOP - VSYSCALL_ADDR) >> PAGE_SHIFT,
82#endif
83#endif
84 FIX_DBGP_BASE,
85 FIX_EARLYCON_MEM_BASE,
86#ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
87 FIX_OHCI1394_BASE,
88#endif
89#ifdef CONFIG_X86_LOCAL_APIC
90 FIX_APIC_BASE, /* local (CPU) APIC) -- required for SMP or not */
91#endif
92#ifdef CONFIG_X86_IO_APIC
93 FIX_IO_APIC_BASE_0,
94 FIX_IO_APIC_BASE_END = FIX_IO_APIC_BASE_0 + MAX_IO_APICS - 1,
95#endif
96#ifdef CONFIG_X86_32
97 FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
98 FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
99#ifdef CONFIG_PCI_MMCONFIG
100 FIX_PCIE_MCFG,
101#endif
102#endif
103#ifdef CONFIG_PARAVIRT
104 FIX_PARAVIRT_BOOTMAP,
105#endif
106#ifdef CONFIG_X86_INTEL_MID
107 FIX_LNW_VRTC,
108#endif
109
110#ifdef CONFIG_ACPI_APEI_GHES
111 /* Used for GHES mapping from assorted contexts */
112 FIX_APEI_GHES_IRQ,
113 FIX_APEI_GHES_NMI,
114#endif
115
116 __end_of_permanent_fixed_addresses,
117
118 /*
119 * 512 temporary boot-time mappings, used by early_ioremap(),
120 * before ioremap() is functional.
121 *
122 * If necessary we round it up to the next 512 pages boundary so
123 * that we can have a single pgd entry and a single pte table:
124 */
125#define NR_FIX_BTMAPS 64
126#define FIX_BTMAPS_SLOTS 8
127#define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
128 FIX_BTMAP_END =
129 (__end_of_permanent_fixed_addresses ^
130 (__end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS - 1)) &
131 -PTRS_PER_PTE
132 ? __end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS -
133 (__end_of_permanent_fixed_addresses & (TOTAL_FIX_BTMAPS - 1))
134 : __end_of_permanent_fixed_addresses,
135 FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
136#ifdef CONFIG_X86_32
137 FIX_WP_TEST,
138#endif
139#ifdef CONFIG_INTEL_TXT
140 FIX_TBOOT_BASE,
141#endif
142 __end_of_fixed_addresses
143};
144
145
146extern void reserve_top_address(unsigned long reserve);
147
148#define FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT)
149#define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE)
150#define FIXADDR_TOT_SIZE (__end_of_fixed_addresses << PAGE_SHIFT)
151#define FIXADDR_TOT_START (FIXADDR_TOP - FIXADDR_TOT_SIZE)
152
153extern int fixmaps_set;
154
155extern pte_t *kmap_pte;
156#define kmap_prot PAGE_KERNEL
157extern pte_t *pkmap_page_table;
158
159void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
160void native_set_fixmap(enum fixed_addresses idx,
161 phys_addr_t phys, pgprot_t flags);
162
163#ifndef CONFIG_PARAVIRT_XXL
164static inline void __set_fixmap(enum fixed_addresses idx,
165 phys_addr_t phys, pgprot_t flags)
166{
167 native_set_fixmap(idx, phys, flags);
168}
169#endif
170
171/*
172 * FIXMAP_PAGE_NOCACHE is used for MMIO. Memory encryption is not
173 * supported for MMIO addresses, so make sure that the memory encryption
174 * mask is not part of the page attributes.
175 */
176#define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_IO_NOCACHE
177
178/*
179 * Early memremap routines used for in-place encryption. The mappings created
180 * by these routines are intended to be used as temporary mappings.
181 */
182void __init *early_memremap_encrypted(resource_size_t phys_addr,
183 unsigned long size);
184void __init *early_memremap_encrypted_wp(resource_size_t phys_addr,
185 unsigned long size);
186void __init *early_memremap_decrypted(resource_size_t phys_addr,
187 unsigned long size);
188void __init *early_memremap_decrypted_wp(resource_size_t phys_addr,
189 unsigned long size);
190
191#include <asm-generic/fixmap.h>
192
193#define __late_set_fixmap(idx, phys, flags) __set_fixmap(idx, phys, flags)
194#define __late_clear_fixmap(idx) __set_fixmap(idx, 0, __pgprot(0))
195
196void __early_set_fixmap(enum fixed_addresses idx,
197 phys_addr_t phys, pgprot_t flags);
198
199#endif /* !__ASSEMBLY__ */
200#endif /* _ASM_X86_FIXMAP_H */