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/apicdef.h> 30 #include <asm/page.h> 31 #include <asm/pgtable_types.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 extern pte_t *pkmap_page_table; 156 157 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte); 158 void native_set_fixmap(unsigned /* enum fixed_addresses */ idx, 159 phys_addr_t phys, pgprot_t flags); 160 161 #ifndef CONFIG_PARAVIRT_XXL 162 static inline void __set_fixmap(enum fixed_addresses idx, 163 phys_addr_t phys, pgprot_t flags) 164 { 165 native_set_fixmap(idx, phys, flags); 166 } 167 #endif 168 169 /* 170 * FIXMAP_PAGE_NOCACHE is used for MMIO. Memory encryption is not 171 * supported for MMIO addresses, so make sure that the memory encryption 172 * mask is not part of the page attributes. 173 */ 174 #define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_IO_NOCACHE 175 176 /* 177 * Early memremap routines used for in-place encryption. The mappings created 178 * by these routines are intended to be used as temporary mappings. 179 */ 180 void __init *early_memremap_encrypted(resource_size_t phys_addr, 181 unsigned long size); 182 void __init *early_memremap_encrypted_wp(resource_size_t phys_addr, 183 unsigned long size); 184 void __init *early_memremap_decrypted(resource_size_t phys_addr, 185 unsigned long size); 186 void __init *early_memremap_decrypted_wp(resource_size_t phys_addr, 187 unsigned long size); 188 189 #include <asm-generic/fixmap.h> 190 191 #define __late_set_fixmap(idx, phys, flags) __set_fixmap(idx, phys, flags) 192 #define __late_clear_fixmap(idx) __set_fixmap(idx, 0, __pgprot(0)) 193 194 void __early_set_fixmap(enum fixed_addresses idx, 195 phys_addr_t phys, pgprot_t flags); 196 197 #endif /* !__ASSEMBLY__ */ 198 #endif /* _ASM_X86_FIXMAP_H */ 199