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 #include <asm/pvclock.h> 23 #ifdef CONFIG_X86_32 24 #include <linux/threads.h> 25 #include <asm/kmap_types.h> 26 #else 27 #include <asm/vsyscall.h> 28 #endif 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 (VSYSCALL_END-PAGE_SIZE) 45 #endif 46 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 VSYSCALL_LAST_PAGE, 72 VSYSCALL_FIRST_PAGE = VSYSCALL_LAST_PAGE 73 + ((VSYSCALL_END-VSYSCALL_START) >> PAGE_SHIFT) - 1, 74 VVAR_PAGE, 75 VSYSCALL_HPET, 76 #ifdef CONFIG_PARAVIRT_CLOCK 77 PVCLOCK_FIXMAP_BEGIN, 78 PVCLOCK_FIXMAP_END = PVCLOCK_FIXMAP_BEGIN+PVCLOCK_VSYSCALL_NR_PAGES-1, 79 #endif 80 #endif 81 FIX_DBGP_BASE, 82 FIX_EARLYCON_MEM_BASE, 83 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT 84 FIX_OHCI1394_BASE, 85 #endif 86 #ifdef CONFIG_X86_LOCAL_APIC 87 FIX_APIC_BASE, /* local (CPU) APIC) -- required for SMP or not */ 88 #endif 89 #ifdef CONFIG_X86_IO_APIC 90 FIX_IO_APIC_BASE_0, 91 FIX_IO_APIC_BASE_END = FIX_IO_APIC_BASE_0 + MAX_IO_APICS - 1, 92 #endif 93 FIX_RO_IDT, /* Virtual mapping for read-only IDT */ 94 #ifdef CONFIG_X86_32 95 FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */ 96 FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1, 97 #ifdef CONFIG_PCI_MMCONFIG 98 FIX_PCIE_MCFG, 99 #endif 100 #endif 101 #ifdef CONFIG_PARAVIRT 102 FIX_PARAVIRT_BOOTMAP, 103 #endif 104 FIX_TEXT_POKE1, /* reserve 2 pages for text_poke() */ 105 FIX_TEXT_POKE0, /* first page is last, because allocation is backward */ 106 #ifdef CONFIG_X86_INTEL_MID 107 FIX_LNW_VRTC, 108 #endif 109 __end_of_permanent_fixed_addresses, 110 111 /* 112 * 256 temporary boot-time mappings, used by early_ioremap(), 113 * before ioremap() is functional. 114 * 115 * If necessary we round it up to the next 256 pages boundary so 116 * that we can have a single pgd entry and a single pte table: 117 */ 118 #define NR_FIX_BTMAPS 64 119 #define FIX_BTMAPS_SLOTS 4 120 #define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS) 121 FIX_BTMAP_END = 122 (__end_of_permanent_fixed_addresses ^ 123 (__end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS - 1)) & 124 -PTRS_PER_PTE 125 ? __end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS - 126 (__end_of_permanent_fixed_addresses & (TOTAL_FIX_BTMAPS - 1)) 127 : __end_of_permanent_fixed_addresses, 128 FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1, 129 #ifdef CONFIG_X86_32 130 FIX_WP_TEST, 131 #endif 132 #ifdef CONFIG_INTEL_TXT 133 FIX_TBOOT_BASE, 134 #endif 135 __end_of_fixed_addresses 136 }; 137 138 139 extern void reserve_top_address(unsigned long reserve); 140 141 #define FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT) 142 #define FIXADDR_BOOT_SIZE (__end_of_fixed_addresses << PAGE_SHIFT) 143 #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) 144 #define FIXADDR_BOOT_START (FIXADDR_TOP - FIXADDR_BOOT_SIZE) 145 146 extern int fixmaps_set; 147 148 extern pte_t *kmap_pte; 149 extern pgprot_t kmap_prot; 150 extern pte_t *pkmap_page_table; 151 152 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte); 153 void native_set_fixmap(enum fixed_addresses idx, 154 phys_addr_t phys, pgprot_t flags); 155 156 #ifndef CONFIG_PARAVIRT 157 static inline void __set_fixmap(enum fixed_addresses idx, 158 phys_addr_t phys, pgprot_t flags) 159 { 160 native_set_fixmap(idx, phys, flags); 161 } 162 #endif 163 164 #include <asm-generic/fixmap.h> 165 166 #define __late_set_fixmap(idx, phys, flags) __set_fixmap(idx, phys, flags) 167 #define __late_clear_fixmap(idx) __set_fixmap(idx, 0, __pgprot(0)) 168 169 void __early_set_fixmap(enum fixed_addresses idx, 170 phys_addr_t phys, pgprot_t flags); 171 172 #endif /* !__ASSEMBLY__ */ 173 #endif /* _ASM_X86_FIXMAP_H */ 174