linux/include/asm-x86/fixmap_64.h
Yinghai Lu c1a2f4b108 x86: change early_ioremap to use slots instead of nesting
so we could remove the requirement that one needs to call
early_iounmap() in exactly reverse order of early_ioremap().

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-13 10:34:23 +02:00

84 lines
2.5 KiB
C

/*
* fixmap.h: compile-time virtual memory allocation
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1998 Ingo Molnar
*/
#ifndef ASM_X86__FIXMAP_64_H
#define ASM_X86__FIXMAP_64_H
#include <linux/kernel.h>
#include <asm/acpi.h>
#include <asm/apicdef.h>
#include <asm/page.h>
#include <asm/vsyscall.h>
#include <asm/efi.h>
/*
* Here we define all the compile-time 'special' virtual
* addresses. The point is to have a constant address at
* compile time, but to set the physical address only
* in the boot process.
*
* These 'compile-time allocated' memory buffers are
* fixed-size 4k pages (or larger if used with an increment
* higher than 1). Use set_fixmap(idx,phys) to associate
* physical memory with fixmap indices.
*
* TLB entries of such buffers will not be flushed across
* task switches.
*/
enum fixed_addresses {
VSYSCALL_LAST_PAGE,
VSYSCALL_FIRST_PAGE = VSYSCALL_LAST_PAGE
+ ((VSYSCALL_END-VSYSCALL_START) >> PAGE_SHIFT) - 1,
VSYSCALL_HPET,
FIX_DBGP_BASE,
FIX_EARLYCON_MEM_BASE,
FIX_APIC_BASE, /* local (CPU) APIC) -- required for SMP or not */
FIX_IO_APIC_BASE_0,
FIX_IO_APIC_BASE_END = FIX_IO_APIC_BASE_0 + MAX_IO_APICS - 1,
FIX_EFI_IO_MAP_LAST_PAGE,
FIX_EFI_IO_MAP_FIRST_PAGE = FIX_EFI_IO_MAP_LAST_PAGE
+ MAX_EFI_IO_PAGES - 1,
#ifdef CONFIG_PARAVIRT
FIX_PARAVIRT_BOOTMAP,
#endif
__end_of_permanent_fixed_addresses,
#ifdef CONFIG_ACPI
FIX_ACPI_BEGIN,
FIX_ACPI_END = FIX_ACPI_BEGIN + FIX_ACPI_PAGES - 1,
#endif
#ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
FIX_OHCI1394_BASE,
#endif
/*
* 256 temporary boot-time mappings, used by early_ioremap(),
* before ioremap() is functional.
*
* We round it up to the next 256 pages boundary so that we
* can have a single pgd entry and a single pte table:
*/
#define NR_FIX_BTMAPS 64
#define FIX_BTMAPS_SLOTS 4
FIX_BTMAP_END = __end_of_permanent_fixed_addresses + 256 -
(__end_of_permanent_fixed_addresses & 255),
FIX_BTMAP_BEGIN = FIX_BTMAP_END + NR_FIX_BTMAPS*FIX_BTMAPS_SLOTS - 1,
__end_of_fixed_addresses
};
#define FIXADDR_TOP (VSYSCALL_END-PAGE_SIZE)
#define FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT)
#define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE)
/* Only covers 32bit vsyscalls currently. Need another set for 64bit. */
#define FIXADDR_USER_START ((unsigned long)VSYSCALL32_VSYSCALL)
#define FIXADDR_USER_END (FIXADDR_USER_START + PAGE_SIZE)
#endif /* ASM_X86__FIXMAP_64_H */