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 <uapi/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 (round_up(VSYSCALL_ADDR + PAGE_SIZE, 1<<PMD_SHIFT) - \ 45 PAGE_SIZE) 46 #endif 47 48 49 /* 50 * Here we define all the compile-time 'special' virtual 51 * addresses. The point is to have a constant address at 52 * compile time, but to set the physical address only 53 * in the boot process. 54 * for x86_32: We allocate these special addresses 55 * from the end of virtual memory (0xfffff000) backwards. 56 * Also this lets us do fail-safe vmalloc(), we 57 * can guarantee that these special addresses and 58 * vmalloc()-ed addresses never overlap. 59 * 60 * These 'compile-time allocated' memory buffers are 61 * fixed-size 4k pages (or larger if used with an increment 62 * higher than 1). Use set_fixmap(idx,phys) to associate 63 * physical memory with fixmap indices. 64 * 65 * TLB entries of such buffers will not be flushed across 66 * task switches. 67 */ 68 enum fixed_addresses { 69 #ifdef CONFIG_X86_32 70 FIX_HOLE, 71 #else 72 #ifdef CONFIG_X86_VSYSCALL_EMULATION 73 VSYSCALL_PAGE = (FIXADDR_TOP - VSYSCALL_ADDR) >> PAGE_SHIFT, 74 #endif 75 #ifdef CONFIG_PARAVIRT_CLOCK 76 PVCLOCK_FIXMAP_BEGIN, 77 PVCLOCK_FIXMAP_END = PVCLOCK_FIXMAP_BEGIN+PVCLOCK_VSYSCALL_NR_PAGES-1, 78 #endif 79 #endif 80 FIX_DBGP_BASE, 81 FIX_EARLYCON_MEM_BASE, 82 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT 83 FIX_OHCI1394_BASE, 84 #endif 85 #ifdef CONFIG_X86_LOCAL_APIC 86 FIX_APIC_BASE, /* local (CPU) APIC) -- required for SMP or not */ 87 #endif 88 #ifdef CONFIG_X86_IO_APIC 89 FIX_IO_APIC_BASE_0, 90 FIX_IO_APIC_BASE_END = FIX_IO_APIC_BASE_0 + MAX_IO_APICS - 1, 91 #endif 92 FIX_RO_IDT, /* Virtual mapping for read-only IDT */ 93 #ifdef CONFIG_X86_32 94 FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */ 95 FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1, 96 #ifdef CONFIG_PCI_MMCONFIG 97 FIX_PCIE_MCFG, 98 #endif 99 #endif 100 #ifdef CONFIG_PARAVIRT 101 FIX_PARAVIRT_BOOTMAP, 102 #endif 103 FIX_TEXT_POKE1, /* reserve 2 pages for text_poke() */ 104 FIX_TEXT_POKE0, /* first page is last, because allocation is backward */ 105 #ifdef CONFIG_X86_INTEL_MID 106 FIX_LNW_VRTC, 107 #endif 108 __end_of_permanent_fixed_addresses, 109 110 /* 111 * 512 temporary boot-time mappings, used by early_ioremap(), 112 * before ioremap() is functional. 113 * 114 * If necessary we round it up to the next 512 pages boundary so 115 * that we can have a single pgd entry and a single pte table: 116 */ 117 #define NR_FIX_BTMAPS 64 118 #define FIX_BTMAPS_SLOTS 8 119 #define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS) 120 FIX_BTMAP_END = 121 (__end_of_permanent_fixed_addresses ^ 122 (__end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS - 1)) & 123 -PTRS_PER_PTE 124 ? __end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS - 125 (__end_of_permanent_fixed_addresses & (TOTAL_FIX_BTMAPS - 1)) 126 : __end_of_permanent_fixed_addresses, 127 FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1, 128 #ifdef CONFIG_X86_32 129 FIX_WP_TEST, 130 #endif 131 #ifdef CONFIG_INTEL_TXT 132 FIX_TBOOT_BASE, 133 #endif 134 __end_of_fixed_addresses 135 }; 136 137 138 extern void reserve_top_address(unsigned long reserve); 139 140 #define FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT) 141 #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) 142 143 extern int fixmaps_set; 144 145 extern pte_t *kmap_pte; 146 extern pgprot_t kmap_prot; 147 extern pte_t *pkmap_page_table; 148 149 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte); 150 void native_set_fixmap(enum fixed_addresses idx, 151 phys_addr_t phys, pgprot_t flags); 152 153 #ifndef CONFIG_PARAVIRT 154 static inline void __set_fixmap(enum fixed_addresses idx, 155 phys_addr_t phys, pgprot_t flags) 156 { 157 native_set_fixmap(idx, phys, flags); 158 } 159 #endif 160 161 #include <asm-generic/fixmap.h> 162 163 #define __late_set_fixmap(idx, phys, flags) __set_fixmap(idx, phys, flags) 164 #define __late_clear_fixmap(idx) __set_fixmap(idx, 0, __pgprot(0)) 165 166 void __early_set_fixmap(enum fixed_addresses idx, 167 phys_addr_t phys, pgprot_t flags); 168 169 #endif /* !__ASSEMBLY__ */ 170 #endif /* _ASM_X86_FIXMAP_H */ 171