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#include <asm/kmap_size.h>
18
19/*
20 * Exposed to assembly code for setting up initial page tables. Cannot be
21 * calculated in assembly code (fixmap entries are an enum), but is sanity
22 * checked in the actual fixmap C code to make sure that the fixmap is
23 * covered fully.
24 */
25#ifndef CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP
26# define FIXMAP_PMD_NUM 2
27#else
28# define KM_PMDS (KM_MAX_IDX * ((CONFIG_NR_CPUS + 511) / 512))
29# define FIXMAP_PMD_NUM (KM_PMDS + 2)
30#endif
31/* fixmap starts downwards from the 507th entry in level2_fixmap_pgt */
32#define FIXMAP_PMD_TOP 507
33
34#ifndef __ASSEMBLER__
35#include <linux/kernel.h>
36#include <asm/apicdef.h>
37#include <asm/page.h>
38#include <asm/pgtable_types.h>
39#ifdef CONFIG_X86_32
40#include <linux/threads.h>
41#else
42#include <uapi/asm/vsyscall.h>
43#endif
44
45/*
46 * We can't declare FIXADDR_TOP as variable for x86_64 because vsyscall
47 * uses fixmaps that relies on FIXADDR_TOP for proper address calculation.
48 * Because of this, FIXADDR_TOP x86 integration was left as later work.
49 */
50#ifdef CONFIG_X86_32
51/*
52 * Leave one empty page between vmalloc'ed areas and
53 * the start of the fixmap.
54 */
55extern unsigned long __FIXADDR_TOP;
56#define FIXADDR_TOP ((unsigned long)__FIXADDR_TOP)
57#else
58#define FIXADDR_TOP (round_up(VSYSCALL_ADDR + PAGE_SIZE, 1<<PMD_SHIFT) - \
59 PAGE_SIZE)
60#endif
61
62/*
63 * Here we define all the compile-time 'special' virtual
64 * addresses. The point is to have a constant address at
65 * compile time, but to set the physical address only
66 * in the boot process.
67 * for x86_32: We allocate these special addresses
68 * from the end of virtual memory (0xfffff000) backwards.
69 * Also this lets us do fail-safe vmalloc(), we
70 * can guarantee that these special addresses and
71 * vmalloc()-ed addresses never overlap.
72 *
73 * These 'compile-time allocated' memory buffers are
74 * fixed-size 4k pages (or larger if used with an increment
75 * higher than 1). Use set_fixmap(idx,phys) to associate
76 * physical memory with fixmap indices.
77 *
78 * TLB entries of such buffers will not be flushed across
79 * task switches.
80 */
81enum fixed_addresses {
82#ifdef CONFIG_X86_32
83 FIX_HOLE,
84#else
85#ifdef CONFIG_X86_VSYSCALL_EMULATION
86 VSYSCALL_PAGE = (FIXADDR_TOP - VSYSCALL_ADDR) >> PAGE_SHIFT,
87#endif
88#endif
89 FIX_DBGP_BASE,
90 FIX_EARLYCON_MEM_BASE,
91#ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
92 FIX_OHCI1394_BASE,
93#endif
94#ifdef CONFIG_X86_LOCAL_APIC
95 FIX_APIC_BASE, /* local (CPU) APIC) -- required for SMP or not */
96#endif
97#ifdef CONFIG_X86_IO_APIC
98 FIX_IO_APIC_BASE_0,
99 FIX_IO_APIC_BASE_END = FIX_IO_APIC_BASE_0 + MAX_IO_APICS - 1,
100#endif
101#ifdef CONFIG_KMAP_LOCAL
102 FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
103 FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
104#ifdef CONFIG_PCI_MMCONFIG
105 FIX_PCIE_MCFG,
106#endif
107#endif
108#ifdef CONFIG_PARAVIRT_XXL
109 FIX_PARAVIRT_BOOTMAP,
110#endif
111
112#ifdef CONFIG_ACPI_APEI_GHES
113 /* Used for GHES mapping from assorted contexts */
114 FIX_APEI_GHES_IRQ,
115 FIX_APEI_GHES_NMI,
116#endif
117
118 __end_of_permanent_fixed_addresses,
119
120 /*
121 * 512 temporary boot-time mappings, used by early_ioremap(),
122 * before ioremap() is functional.
123 *
124 * If necessary we round it up to the next 512 pages boundary so
125 * that we can have a single pmd entry and a single pte table:
126 */
127#define NR_FIX_BTMAPS 64
128#define FIX_BTMAPS_SLOTS 8
129#define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
130 FIX_BTMAP_END =
131 (__end_of_permanent_fixed_addresses ^
132 (__end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS - 1)) &
133 -PTRS_PER_PTE
134 ? __end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS -
135 (__end_of_permanent_fixed_addresses & (TOTAL_FIX_BTMAPS - 1))
136 : __end_of_permanent_fixed_addresses,
137 FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
138#ifdef CONFIG_X86_32
139 FIX_WP_TEST,
140#endif
141#ifdef CONFIG_INTEL_TXT
142 FIX_TBOOT_BASE,
143#endif
144 __end_of_fixed_addresses
145};
146
147
148extern void reserve_top_address(unsigned long reserve);
149
150#define FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT)
151#define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE)
152#define FIXADDR_TOT_SIZE (__end_of_fixed_addresses << PAGE_SHIFT)
153#define FIXADDR_TOT_START (FIXADDR_TOP - FIXADDR_TOT_SIZE)
154
155extern int fixmaps_set;
156
157extern pte_t *pkmap_page_table;
158
159void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
160void native_set_fixmap(unsigned /* 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 /* !__ASSEMBLER__ */
200#endif /* _ASM_X86_FIXMAP_H */
201