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 #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
  29 /*
  30  * We can't declare FIXADDR_TOP as variable for x86_64 because vsyscall
  31  * uses fixmaps that relies on FIXADDR_TOP for proper address calculation.
  32  * Because of this, FIXADDR_TOP x86 integration was left as later work.
  33  */
  34 #ifdef CONFIG_X86_32
  35 /* used by vmalloc.c, vsyscall.lds.S.
  36  *
  37  * Leave one empty page between vmalloc'ed areas and
  38  * the start of the fixmap.
  39  */
  40 extern unsigned long __FIXADDR_TOP;
  41 #define FIXADDR_TOP     ((unsigned long)__FIXADDR_TOP)
  42 #else
  43 #define FIXADDR_TOP     (round_up(VSYSCALL_ADDR + PAGE_SIZE, 1<<PMD_SHIFT) - \
  44                          PAGE_SIZE)
  45 #endif
  46
  47 /*
  48  * Here we define all the compile-time 'special' virtual
  49  * addresses. The point is to have a constant address at
  50  * compile time, but to set the physical address only
  51  * in the boot process.
  52  * for x86_32: We allocate these special addresses
  53  * from the end of virtual memory (0xfffff000) backwards.
  54  * Also this lets us do fail-safe vmalloc(), we
  55  * can guarantee that these special addresses and
  56  * vmalloc()-ed addresses never overlap.
  57  *
  58  * These 'compile-time allocated' memory buffers are
  59  * fixed-size 4k pages (or larger if used with an increment
  60  * higher than 1). Use set_fixmap(idx,phys) to associate
  61  * physical memory with fixmap indices.
  62  *
  63  * TLB entries of such buffers will not be flushed across
  64  * task switches.
  65  */
  66 enum fixed_addresses {
  67 #ifdef CONFIG_X86_32
  68         FIX_HOLE,
  69 #else
  70 #ifdef CONFIG_X86_VSYSCALL_EMULATION
  71         VSYSCALL_PAGE = (FIXADDR_TOP - VSYSCALL_ADDR) >> PAGE_SHIFT,
  72 #endif
  73 #endif
  74         FIX_DBGP_BASE,
  75         FIX_EARLYCON_MEM_BASE,
  76 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
  77         FIX_OHCI1394_BASE,
  78 #endif
  79 #ifdef CONFIG_X86_LOCAL_APIC
  80         FIX_APIC_BASE,  /* local (CPU) APIC) -- required for SMP or not */
  81 #endif
  82 #ifdef CONFIG_X86_IO_APIC
  83         FIX_IO_APIC_BASE_0,
  84         FIX_IO_APIC_BASE_END = FIX_IO_APIC_BASE_0 + MAX_IO_APICS - 1,
  85 #endif
  86 #ifdef CONFIG_X86_32
  87         FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
  88         FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
  89 #ifdef CONFIG_PCI_MMCONFIG
  90         FIX_PCIE_MCFG,
  91 #endif
  92 #endif
  93 #ifdef CONFIG_PARAVIRT
  94         FIX_PARAVIRT_BOOTMAP,
  95 #endif
  96         FIX_TEXT_POKE1, /* reserve 2 pages for text_poke() */
  97         FIX_TEXT_POKE0, /* first page is last, because allocation is backward */
  98 #ifdef  CONFIG_X86_INTEL_MID
  99         FIX_LNW_VRTC,
 100 #endif
 101
 102 #ifdef CONFIG_ACPI_APEI_GHES
 103         /* Used for GHES mapping from assorted contexts */
 104         FIX_APEI_GHES_IRQ,
 105         FIX_APEI_GHES_NMI,
 106 #endif
 107
 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 #define FIXADDR_TOT_SIZE        (__end_of_fixed_addresses << PAGE_SHIFT)
 143 #define FIXADDR_TOT_START       (FIXADDR_TOP - FIXADDR_TOT_SIZE)
 144
 145 extern int fixmaps_set;
 146
 147 extern pte_t *kmap_pte;
 148 #define kmap_prot PAGE_KERNEL
 149 extern pte_t *pkmap_page_table;
 150
 151 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
 152 void native_set_fixmap(enum fixed_addresses idx,
 153                        phys_addr_t phys, pgprot_t flags);
 154
 155 #ifndef CONFIG_PARAVIRT
 156 static inline void __set_fixmap(enum fixed_addresses idx,
 157                                 phys_addr_t phys, pgprot_t flags)
 158 {
 159         native_set_fixmap(idx, phys, flags);
 160 }
 161 #endif
 162
 163 /*
 164  * FIXMAP_PAGE_NOCACHE is used for MMIO. Memory encryption is not
 165  * supported for MMIO addresses, so make sure that the memory encryption
 166  * mask is not part of the page attributes.
 167  */
 168 #define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_IO_NOCACHE
 169
 170 /*
 171  * Early memremap routines used for in-place encryption. The mappings created
 172  * by these routines are intended to be used as temporary mappings.
 173  */
 174 void __init *early_memremap_encrypted(resource_size_t phys_addr,
 175                                       unsigned long size);
 176 void __init *early_memremap_encrypted_wp(resource_size_t phys_addr,
 177                                          unsigned long size);
 178 void __init *early_memremap_decrypted(resource_size_t phys_addr,
 179                                       unsigned long size);
 180 void __init *early_memremap_decrypted_wp(resource_size_t phys_addr,
 181                                          unsigned long size);
 182
 183 #include <asm-generic/fixmap.h>
 184
 185 #define __late_set_fixmap(idx, phys, flags) __set_fixmap(idx, phys, flags)
 186 #define __late_clear_fixmap(idx) __set_fixmap(idx, 0, __pgprot(0))
 187
 188 void __early_set_fixmap(enum fixed_addresses idx,
 189                         phys_addr_t phys, pgprot_t flags);
 190
 191 #endif /* !__ASSEMBLY__ */
 192 #endif /* _ASM_X86_FIXMAP_H */