cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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fixmap.h (2219B)

      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 */
     12
     13#ifndef _ASM_FIXMAP_H
     14#define _ASM_FIXMAP_H
     15
     16#include <asm/page.h>
     17#include <spaces.h>
     18#ifdef CONFIG_HIGHMEM
     19#include <linux/threads.h>
     20#include <asm/kmap_size.h>
     21#endif
     22
     23/*
     24 * Here we define all the compile-time 'special' virtual
     25 * addresses. The point is to have a constant address at
     26 * compile time, but to set the physical address only
     27 * in the boot process. We allocate these special  addresses
     28 * from the end of virtual memory (0xfffff000) backwards.
     29 * Also this lets us do fail-safe vmalloc(), we
     30 * can guarantee that these special addresses and
     31 * vmalloc()-ed addresses never overlap.
     32 *
     33 * these 'compile-time allocated' memory buffers are
     34 * fixed-size 4k pages. (or larger if used with an increment
     35 * highger than 1) use fixmap_set(idx,phys) to associate
     36 * physical memory with fixmap indices.
     37 *
     38 * TLB entries of such buffers will not be flushed across
     39 * task switches.
     40 */
     41
     42/*
     43 * on UP currently we will have no trace of the fixmap mechanizm,
     44 * no page table allocations, etc. This might change in the
     45 * future, say framebuffers for the console driver(s) could be
     46 * fix-mapped?
     47 */
     48enum fixed_addresses {
     49#define FIX_N_COLOURS 8
     50	FIX_CMAP_BEGIN,
     51	FIX_CMAP_END = FIX_CMAP_BEGIN + (FIX_N_COLOURS * 2),
     52#ifdef CONFIG_HIGHMEM
     53	/* reserved pte's for temporary kernel mappings */
     54	FIX_KMAP_BEGIN = FIX_CMAP_END + 1,
     55	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
     56#endif
     57	__end_of_fixed_addresses
     58};
     59
     60/*
     61 * used by vmalloc.c.
     62 *
     63 * Leave one empty page between vmalloc'ed areas and
     64 * the start of the fixmap, and leave one page empty
     65 * at the top of mem..
     66 */
     67#define FIXADDR_SIZE	(__end_of_fixed_addresses << PAGE_SHIFT)
     68#define FIXADDR_START	(FIXADDR_TOP - FIXADDR_SIZE)
     69
     70#include <asm-generic/fixmap.h>
     71
     72/*
     73 * Called from pgtable_init()
     74 */
     75extern void fixrange_init(unsigned long start, unsigned long end,
     76	pgd_t *pgd_base);
     77
     78
     79#endif