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 FIX_TEXT_POKE1, /* reserve 2 pages for text_poke() */
107 FIX_TEXT_POKE0, /* first page is last, because allocation is backward */
108#ifdef CONFIG_X86_INTEL_MID
109 FIX_LNW_VRTC,
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 pgd 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 *kmap_pte;
158#define kmap_prot PAGE_KERNEL
159extern pte_t *pkmap_page_table;
160
161void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
162void native_set_fixmap(enum fixed_addresses idx,
163 phys_addr_t phys, pgprot_t flags);
164
165#ifndef CONFIG_PARAVIRT_XXL
166static inline void __set_fixmap(enum fixed_addresses idx,
167 phys_addr_t phys, pgprot_t flags)
168{
169 native_set_fixmap(idx, phys, flags);
170}
171#endif
172
173/*
174 * FIXMAP_PAGE_NOCACHE is used for MMIO. Memory encryption is not
175 * supported for MMIO addresses, so make sure that the memory encryption
176 * mask is not part of the page attributes.
177 */
178#define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_IO_NOCACHE
179
180/*
181 * Early memremap routines used for in-place encryption. The mappings created
182 * by these routines are intended to be used as temporary mappings.
183 */
184void __init *early_memremap_encrypted(resource_size_t phys_addr,
185 unsigned long size);
186void __init *early_memremap_encrypted_wp(resource_size_t phys_addr,
187 unsigned long size);
188void __init *early_memremap_decrypted(resource_size_t phys_addr,
189 unsigned long size);
190void __init *early_memremap_decrypted_wp(resource_size_t phys_addr,
191 unsigned long size);
192
193#include <asm-generic/fixmap.h>
194
195#define __late_set_fixmap(idx, phys, flags) __set_fixmap(idx, phys, flags)
196#define __late_clear_fixmap(idx) __set_fixmap(idx, 0, __pgprot(0))
197
198void __early_set_fixmap(enum fixed_addresses idx,
199 phys_addr_t phys, pgprot_t flags);
200
201#endif /* !__ASSEMBLY__ */
202#endif /* _ASM_X86_FIXMAP_H */
203