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 #ifndef __ASSEMBLY__ 18 #include <linux/kernel.h> 19 #include <asm/acpi.h> 20 #include <asm/apicdef.h> 21 #include <asm/page.h> 22 #ifdef CONFIG_X86_32 23 #include <linux/threads.h> 24 #include <asm/kmap_types.h> 25 #else 26 #include <uapi/asm/vsyscall.h> 27 #endif 28 #include <asm/cpu_entry_area.h> 29 30 /* 31 * We can't declare FIXADDR_TOP as variable for x86_64 because vsyscall 32 * uses fixmaps that relies on FIXADDR_TOP for proper address calculation. 33 * Because of this, FIXADDR_TOP x86 integration was left as later work. 34 */ 35 #ifdef CONFIG_X86_32 36 /* used by vmalloc.c, vsyscall.lds.S. 37 * 38 * Leave one empty page between vmalloc'ed areas and 39 * the start of the fixmap. 40 */ 41 extern unsigned long __FIXADDR_TOP; 42 #define FIXADDR_TOP ((unsigned long)__FIXADDR_TOP) 43 #else 44 #define FIXADDR_TOP (round_up(VSYSCALL_ADDR + PAGE_SIZE, 1<<PMD_SHIFT) - \ 45 PAGE_SIZE) 46 #endif 47 48 /* 49 * Here we define all the compile-time 'special' virtual 50 * addresses. The point is to have a constant address at 51 * compile time, but to set the physical address only 52 * in the boot process. 53 * for x86_32: We allocate these special addresses 54 * from the end of virtual memory (0xfffff000) backwards. 55 * Also this lets us do fail-safe vmalloc(), we 56 * can guarantee that these special addresses and 57 * vmalloc()-ed addresses never overlap. 58 * 59 * These 'compile-time allocated' memory buffers are 60 * fixed-size 4k pages (or larger if used with an increment 61 * higher than 1). Use set_fixmap(idx,phys) to associate 62 * physical memory with fixmap indices. 63 * 64 * TLB entries of such buffers will not be flushed across 65 * task switches. 66 */ 67 enum fixed_addresses { 68 #ifdef CONFIG_X86_32 69 FIX_HOLE, 70 #else 71 #ifdef CONFIG_X86_VSYSCALL_EMULATION 72 VSYSCALL_PAGE = (FIXADDR_TOP - VSYSCALL_ADDR) >> PAGE_SHIFT, 73 #endif 74 #endif 75 FIX_DBGP_BASE, 76 FIX_EARLYCON_MEM_BASE, 77 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT 78 FIX_OHCI1394_BASE, 79 #endif 80 #ifdef CONFIG_X86_LOCAL_APIC 81 FIX_APIC_BASE, /* local (CPU) APIC) -- required for SMP or not */ 82 #endif 83 #ifdef CONFIG_X86_IO_APIC 84 FIX_IO_APIC_BASE_0, 85 FIX_IO_APIC_BASE_END = FIX_IO_APIC_BASE_0 + MAX_IO_APICS - 1, 86 #endif 87 FIX_RO_IDT, /* Virtual mapping for read-only IDT */ 88 #ifdef CONFIG_X86_32 89 FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */ 90 FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1, 91 #ifdef CONFIG_PCI_MMCONFIG 92 FIX_PCIE_MCFG, 93 #endif 94 #endif 95 #ifdef CONFIG_PARAVIRT 96 FIX_PARAVIRT_BOOTMAP, 97 #endif 98 FIX_TEXT_POKE1, /* reserve 2 pages for text_poke() */ 99 FIX_TEXT_POKE0, /* first page is last, because allocation is backward */ 100 #ifdef CONFIG_X86_INTEL_MID 101 FIX_LNW_VRTC, 102 #endif 103 /* Fixmap entries to remap the GDTs, one per processor. */ 104 FIX_CPU_ENTRY_AREA_TOP, 105 FIX_CPU_ENTRY_AREA_BOTTOM = FIX_CPU_ENTRY_AREA_TOP + (CPU_ENTRY_AREA_PAGES * NR_CPUS) - 1, 106 107 #ifdef CONFIG_ACPI_APEI_GHES 108 /* Used for GHES mapping from assorted contexts */ 109 FIX_APEI_GHES_IRQ, 110 FIX_APEI_GHES_NMI, 111 #endif 112 113 __end_of_permanent_fixed_addresses, 114 115 /* 116 * 512 temporary boot-time mappings, used by early_ioremap(), 117 * before ioremap() is functional. 118 * 119 * If necessary we round it up to the next 512 pages boundary so 120 * that we can have a single pgd entry and a single pte table: 121 */ 122 #define NR_FIX_BTMAPS 64 123 #define FIX_BTMAPS_SLOTS 8 124 #define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS) 125 FIX_BTMAP_END = 126 (__end_of_permanent_fixed_addresses ^ 127 (__end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS - 1)) & 128 -PTRS_PER_PTE 129 ? __end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS - 130 (__end_of_permanent_fixed_addresses & (TOTAL_FIX_BTMAPS - 1)) 131 : __end_of_permanent_fixed_addresses, 132 FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1, 133 #ifdef CONFIG_X86_32 134 FIX_WP_TEST, 135 #endif 136 #ifdef CONFIG_INTEL_TXT 137 FIX_TBOOT_BASE, 138 #endif 139 __end_of_fixed_addresses 140 }; 141 142 143 extern void reserve_top_address(unsigned long reserve); 144 145 #define FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT) 146 #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) 147 148 extern int fixmaps_set; 149 150 extern pte_t *kmap_pte; 151 #define kmap_prot PAGE_KERNEL 152 extern pte_t *pkmap_page_table; 153 154 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte); 155 void native_set_fixmap(enum fixed_addresses idx, 156 phys_addr_t phys, pgprot_t flags); 157 158 #ifndef CONFIG_PARAVIRT 159 static inline void __set_fixmap(enum fixed_addresses idx, 160 phys_addr_t phys, pgprot_t flags) 161 { 162 native_set_fixmap(idx, phys, flags); 163 } 164 #endif 165 166 /* 167 * FIXMAP_PAGE_NOCACHE is used for MMIO. Memory encryption is not 168 * supported for MMIO addresses, so make sure that the memory encryption 169 * mask is not part of the page attributes. 170 */ 171 #define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_IO_NOCACHE 172 173 /* 174 * Early memremap routines used for in-place encryption. The mappings created 175 * by these routines are intended to be used as temporary mappings. 176 */ 177 void __init *early_memremap_encrypted(resource_size_t phys_addr, 178 unsigned long size); 179 void __init *early_memremap_encrypted_wp(resource_size_t phys_addr, 180 unsigned long size); 181 void __init *early_memremap_decrypted(resource_size_t phys_addr, 182 unsigned long size); 183 void __init *early_memremap_decrypted_wp(resource_size_t phys_addr, 184 unsigned long size); 185 186 #include <asm-generic/fixmap.h> 187 188 #define __late_set_fixmap(idx, phys, flags) __set_fixmap(idx, phys, flags) 189 #define __late_clear_fixmap(idx) __set_fixmap(idx, 0, __pgprot(0)) 190 191 void __early_set_fixmap(enum fixed_addresses idx, 192 phys_addr_t phys, pgprot_t flags); 193 194 static inline unsigned int __get_cpu_entry_area_page_index(int cpu, int page) 195 { 196 BUILD_BUG_ON(sizeof(struct cpu_entry_area) % PAGE_SIZE != 0); 197 198 return FIX_CPU_ENTRY_AREA_BOTTOM - cpu*CPU_ENTRY_AREA_PAGES - page; 199 } 200 201 #define __get_cpu_entry_area_offset_index(cpu, offset) ({ \ 202 BUILD_BUG_ON(offset % PAGE_SIZE != 0); \ 203 __get_cpu_entry_area_page_index(cpu, offset / PAGE_SIZE); \ 204 }) 205 206 #define get_cpu_entry_area_index(cpu, field) \ 207 __get_cpu_entry_area_offset_index((cpu), offsetof(struct cpu_entry_area, field)) 208 209 static inline struct cpu_entry_area *get_cpu_entry_area(int cpu) 210 { 211 return (struct cpu_entry_area *)__fix_to_virt(__get_cpu_entry_area_page_index(cpu, 0)); 212 } 213 214 static inline struct entry_stack *cpu_entry_stack(int cpu) 215 { 216 return &get_cpu_entry_area(cpu)->entry_stack_page.stack; 217 } 218 219 #endif /* !__ASSEMBLY__ */ 220 #endif /* _ASM_X86_FIXMAP_H */ 221