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