arch/x86/include/asm/fixmap.h

   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 #include <asm/kmap_size.h>
  18
  19 /*
  20  * Exposed to assembly code for setting up initial page tables. Cannot be
  21  * calculated in assembly code (fixmap entries are an enum), but is sanity
  22  * checked in the actual fixmap C code to make sure that the fixmap is
  23  * covered fully.
  24  */
  25 #ifndef CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP
  26 # define FIXMAP_PMD_NUM 2
  27 #else
  28 # define KM_PMDS        (KM_MAX_IDX * ((CONFIG_NR_CPUS + 511) / 512))
  29 # define FIXMAP_PMD_NUM (KM_PMDS + 2)
  30 #endif
  31 /* fixmap starts downwards from the 507th entry in level2_fixmap_pgt */
  32 #define FIXMAP_PMD_TOP  507
  33
  34 #ifndef __ASSEMBLY__
  35 #include <linux/kernel.h>
  36 #include <asm/apicdef.h>
  37 #include <asm/page.h>
  38 #include <asm/pgtable_types.h>
  39 #ifdef CONFIG_X86_32
  40 #include <linux/threads.h>
  41 #else
  42 #include <uapi/asm/vsyscall.h>
  43 #endif
  44
  45 /*
  46  * We can't declare FIXADDR_TOP as variable for x86_64 because vsyscall
  47  * uses fixmaps that relies on FIXADDR_TOP for proper address calculation.
  48  * Because of this, FIXADDR_TOP x86 integration was left as later work.
  49  */
  50 #ifdef CONFIG_X86_32
  51 /*
  52  * Leave one empty page between vmalloc'ed areas and
  53  * the start of the fixmap.
  54  */
  55 extern unsigned long __FIXADDR_TOP;
  56 #define FIXADDR_TOP     ((unsigned long)__FIXADDR_TOP)
  57 #else
  58 #define FIXADDR_TOP     (round_up(VSYSCALL_ADDR + PAGE_SIZE, 1<<PMD_SHIFT) - \
  59                          PAGE_SIZE)
  60 #endif
  61
  62 /*
  63  * Here we define all the compile-time 'special' virtual
  64  * addresses. The point is to have a constant address at
  65  * compile time, but to set the physical address only
  66  * in the boot process.
  67  * for x86_32: We allocate these special addresses
  68  * from the end of virtual memory (0xfffff000) backwards.
  69  * Also this lets us do fail-safe vmalloc(), we
  70  * can guarantee that these special addresses and
  71  * vmalloc()-ed addresses never overlap.
  72  *
  73  * These 'compile-time allocated' memory buffers are
  74  * fixed-size 4k pages (or larger if used with an increment
  75  * higher than 1). Use set_fixmap(idx,phys) to associate
  76  * physical memory with fixmap indices.
  77  *
  78  * TLB entries of such buffers will not be flushed across
  79  * task switches.
  80  */
  81 enum fixed_addresses {
  82 #ifdef CONFIG_X86_32
  83         FIX_HOLE,
  84 #else
  85 #ifdef CONFIG_X86_VSYSCALL_EMULATION
  86         VSYSCALL_PAGE = (FIXADDR_TOP - VSYSCALL_ADDR) >> PAGE_SHIFT,
  87 #endif
  88 #endif
  89         FIX_DBGP_BASE,
  90         FIX_EARLYCON_MEM_BASE,
  91 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
  92         FIX_OHCI1394_BASE,
  93 #endif
  94 #ifdef CONFIG_X86_LOCAL_APIC
  95         FIX_APIC_BASE,  /* local (CPU) APIC) -- required for SMP or not */
  96 #endif
  97 #ifdef CONFIG_X86_IO_APIC
  98         FIX_IO_APIC_BASE_0,
  99         FIX_IO_APIC_BASE_END = FIX_IO_APIC_BASE_0 + MAX_IO_APICS - 1,
 100 #endif
 101 #ifdef CONFIG_KMAP_LOCAL
 102         FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
 103         FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
 104 #ifdef CONFIG_PCI_MMCONFIG
 105         FIX_PCIE_MCFG,
 106 #endif
 107 #endif
 108 #ifdef CONFIG_PARAVIRT_XXL
 109         FIX_PARAVIRT_BOOTMAP,
 110 #endif
 111 #ifdef  CONFIG_X86_INTEL_MID
 112         FIX_LNW_VRTC,
 113 #endif
 114
 115 #ifdef CONFIG_ACPI_APEI_GHES
 116         /* Used for GHES mapping from assorted contexts */
 117         FIX_APEI_GHES_IRQ,
 118         FIX_APEI_GHES_NMI,
 119 #endif
 120
 121         __end_of_permanent_fixed_addresses,
 122
 123         /*
 124          * 512 temporary boot-time mappings, used by early_ioremap(),
 125          * before ioremap() is functional.
 126          *
 127          * If necessary we round it up to the next 512 pages boundary so
 128          * that we can have a single pmd entry and a single pte table:
 129          */
 130 #define NR_FIX_BTMAPS           64
 131 #define FIX_BTMAPS_SLOTS        8
 132 #define TOTAL_FIX_BTMAPS        (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
 133         FIX_BTMAP_END =
 134          (__end_of_permanent_fixed_addresses ^
 135           (__end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS - 1)) &
 136          -PTRS_PER_PTE
 137          ? __end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS -
 138            (__end_of_permanent_fixed_addresses & (TOTAL_FIX_BTMAPS - 1))
 139          : __end_of_permanent_fixed_addresses,
 140         FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
 141 #ifdef CONFIG_X86_32
 142         FIX_WP_TEST,
 143 #endif
 144 #ifdef CONFIG_INTEL_TXT
 145         FIX_TBOOT_BASE,
 146 #endif
 147         __end_of_fixed_addresses
 148 };
 149
 150
 151 extern void reserve_top_address(unsigned long reserve);
 152
 153 #define FIXADDR_SIZE            (__end_of_permanent_fixed_addresses << PAGE_SHIFT)
 154 #define FIXADDR_START           (FIXADDR_TOP - FIXADDR_SIZE)
 155 #define FIXADDR_TOT_SIZE        (__end_of_fixed_addresses << PAGE_SHIFT)
 156 #define FIXADDR_TOT_START       (FIXADDR_TOP - FIXADDR_TOT_SIZE)
 157
 158 extern int fixmaps_set;
 159
 160 extern pte_t *pkmap_page_table;
 161
 162 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
 163 void native_set_fixmap(unsigned /* enum fixed_addresses */ idx,
 164                        phys_addr_t phys, pgprot_t flags);
 165
 166 #ifndef CONFIG_PARAVIRT_XXL
 167 static inline void __set_fixmap(enum fixed_addresses idx,
 168                                 phys_addr_t phys, pgprot_t flags)
 169 {
 170         native_set_fixmap(idx, phys, flags);
 171 }
 172 #endif
 173
 174 /*
 175  * FIXMAP_PAGE_NOCACHE is used for MMIO. Memory encryption is not
 176  * supported for MMIO addresses, so make sure that the memory encryption
 177  * mask is not part of the page attributes.
 178  */
 179 #define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_IO_NOCACHE
 180
 181 /*
 182  * Early memremap routines used for in-place encryption. The mappings created
 183  * by these routines are intended to be used as temporary mappings.
 184  */
 185 void __init *early_memremap_encrypted(resource_size_t phys_addr,
 186                                       unsigned long size);
 187 void __init *early_memremap_encrypted_wp(resource_size_t phys_addr,
 188                                          unsigned long size);
 189 void __init *early_memremap_decrypted(resource_size_t phys_addr,
 190                                       unsigned long size);
 191 void __init *early_memremap_decrypted_wp(resource_size_t phys_addr,
 192                                          unsigned long size);
 193
 194 #include <asm-generic/fixmap.h>
 195
 196 #define __late_set_fixmap(idx, phys, flags) __set_fixmap(idx, phys, flags)
 197 #define __late_clear_fixmap(idx) __set_fixmap(idx, 0, __pgprot(0))
 198
 199 void __early_set_fixmap(enum fixed_addresses idx,
 200                         phys_addr_t phys, pgprot_t flags);
 201
 202 #endif /* !__ASSEMBLY__ */
 203 #endif /* _ASM_X86_FIXMAP_H */