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 __ASSEMBLY__
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 */
55 extern 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 */
81 enum 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
148 extern 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
155 extern int fixmaps_set;
156
157 extern pte_t *pkmap_page_table;
158
159 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
160 void native_set_fixmap(unsigned /* enum fixed_addresses */ idx,
161 phys_addr_t phys, pgprot_t flags);
162
163 #ifndef CONFIG_PARAVIRT_XXL
__set_fixmap(enum fixed_addresses idx,phys_addr_t phys,pgprot_t flags)164 static 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 */
182 void __init *early_memremap_encrypted(resource_size_t phys_addr,
183 unsigned long size);
184 void __init *early_memremap_encrypted_wp(resource_size_t phys_addr,
185 unsigned long size);
186 void __init *early_memremap_decrypted(resource_size_t phys_addr,
187 unsigned long size);
188 void __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
196 void __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 */
201