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 #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 #ifdef CONFIG_X86_VISWS_APIC
  94         FIX_CO_CPU,     /* Cobalt timer */
  95         FIX_CO_APIC,    /* Cobalt APIC Redirection Table */
  96         FIX_LI_PCIA,    /* Lithium PCI Bridge A */
  97         FIX_LI_PCIB,    /* Lithium PCI Bridge B */
  98 #endif
  99         FIX_RO_IDT,     /* Virtual mapping for read-only IDT */
 100 #ifdef CONFIG_X86_32
 101         FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
 102         FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
 103 #ifdef CONFIG_PCI_MMCONFIG
 104         FIX_PCIE_MCFG,
 105 #endif
 106 #endif
 107 #ifdef CONFIG_PARAVIRT
 108         FIX_PARAVIRT_BOOTMAP,
 109 #endif
 110         FIX_TEXT_POKE1, /* reserve 2 pages for text_poke() */
 111         FIX_TEXT_POKE0, /* first page is last, because allocation is backward */
 112 #ifdef  CONFIG_X86_INTEL_MID
 113         FIX_LNW_VRTC,
 114 #endif
 115         __end_of_permanent_fixed_addresses,
 116
 117         /*
 118          * 256 temporary boot-time mappings, used by early_ioremap(),
 119          * before ioremap() is functional.
 120          *
 121          * If necessary we round it up to the next 256 pages boundary so
 122          * that we can have a single pgd entry and a single pte table:
 123          */
 124 #define NR_FIX_BTMAPS           64
 125 #define FIX_BTMAPS_SLOTS        4
 126 #define TOTAL_FIX_BTMAPS        (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS)
 127         FIX_BTMAP_END =
 128          (__end_of_permanent_fixed_addresses ^
 129           (__end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS - 1)) &
 130          -PTRS_PER_PTE
 131          ? __end_of_permanent_fixed_addresses + TOTAL_FIX_BTMAPS -
 132            (__end_of_permanent_fixed_addresses & (TOTAL_FIX_BTMAPS - 1))
 133          : __end_of_permanent_fixed_addresses,
 134         FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1,
 135 #ifdef CONFIG_X86_32
 136         FIX_WP_TEST,
 137 #endif
 138 #ifdef CONFIG_INTEL_TXT
 139         FIX_TBOOT_BASE,
 140 #endif
 141         __end_of_fixed_addresses
 142 };
 143
 144
 145 extern void reserve_top_address(unsigned long reserve);
 146
 147 #define FIXADDR_SIZE    (__end_of_permanent_fixed_addresses << PAGE_SHIFT)
 148 #define FIXADDR_BOOT_SIZE       (__end_of_fixed_addresses << PAGE_SHIFT)
 149 #define FIXADDR_START           (FIXADDR_TOP - FIXADDR_SIZE)
 150 #define FIXADDR_BOOT_START      (FIXADDR_TOP - FIXADDR_BOOT_SIZE)
 151
 152 extern int fixmaps_set;
 153
 154 extern pte_t *kmap_pte;
 155 extern pgprot_t kmap_prot;
 156 extern pte_t *pkmap_page_table;
 157
 158 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
 159 void native_set_fixmap(enum fixed_addresses idx,
 160                        phys_addr_t phys, pgprot_t flags);
 161
 162 #ifndef CONFIG_PARAVIRT
 163 static inline void __set_fixmap(enum fixed_addresses idx,
 164                                 phys_addr_t phys, pgprot_t flags)
 165 {
 166         native_set_fixmap(idx, phys, flags);
 167 }
 168 #endif
 169
 170 #include <asm-generic/fixmap.h>
 171
 172 #endif /* !__ASSEMBLY__ */
 173 #endif /* _ASM_X86_FIXMAP_H */