LXR linux/tools/power/acpi/os_specific/service

   1/******************************************************************************
   2 *
   3 * Module Name: osunixmap - Unix OSL for file mappings
   4 *
   5 *****************************************************************************/
   6
   7/*
   8 * Copyright (C) 2000 - 2016, Intel Corp.
   9 * All rights reserved.
  10 *
  11 * Redistribution and use in source and binary forms, with or without
  12 * modification, are permitted provided that the following conditions
  13 * are met:
  14 * 1. Redistributions of source code must retain the above copyright
  15 *    notice, this list of conditions, and the following disclaimer,
  16 *    without modification.
  17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18 *    substantially similar to the "NO WARRANTY" disclaimer below
  19 *    ("Disclaimer") and any redistribution must be conditioned upon
  20 *    including a substantially similar Disclaimer requirement for further
  21 *    binary redistribution.
  22 * 3. Neither the names of the above-listed copyright holders nor the names
  23 *    of any contributors may be used to endorse or promote products derived
  24 *    from this software without specific prior written permission.
  25 *
  26 * Alternatively, this software may be distributed under the terms of the
  27 * GNU General Public License ("GPL") version 2 as published by the Free
  28 * Software Foundation.
  29 *
  30 * NO WARRANTY
  31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41 * POSSIBILITY OF SUCH DAMAGES.
  42 */
  43
  44#include "acpidump.h"
  45#include <unistd.h>
  46#include <sys/mman.h>
  47#ifdef _free_BSD
  48#include <sys/param.h>
  49#endif
  50
  51#define _COMPONENT          ACPI_OS_SERVICES
  52ACPI_MODULE_NAME("osunixmap")
  53
  54#ifndef O_BINARY
  55#define O_BINARY 0
  56#endif
  57#if defined(_dragon_fly) || defined(_free_BSD) || defined(_QNX)
  58#define MMAP_FLAGS          MAP_SHARED
  59#else
  60#define MMAP_FLAGS          MAP_PRIVATE
  61#endif
  62#define SYSTEM_MEMORY       "/dev/mem"
  63/*******************************************************************************
  64 *
  65 * FUNCTION:    acpi_os_get_page_size
  66 *
  67 * PARAMETERS:  None
  68 *
  69 * RETURN:      Page size of the platform.
  70 *
  71 * DESCRIPTION: Obtain page size of the platform.
  72 *
  73 ******************************************************************************/
  74static acpi_size acpi_os_get_page_size(void)
  75{
  76
  77#ifdef PAGE_SIZE
  78        return PAGE_SIZE;
  79#else
  80        return sysconf(_SC_PAGESIZE);
  81#endif
  82}
  83
  84/******************************************************************************
  85 *
  86 * FUNCTION:    acpi_os_map_memory
  87 *
  88 * PARAMETERS:  where               - Physical address of memory to be mapped
  89 *              length              - How much memory to map
  90 *
  91 * RETURN:      Pointer to mapped memory. Null on error.
  92 *
  93 * DESCRIPTION: Map physical memory into local address space.
  94 *
  95 *****************************************************************************/
  96
  97void *acpi_os_map_memory(acpi_physical_address where, acpi_size length)
  98{
  99        u8 *mapped_memory;
 100        acpi_physical_address offset;
 101        acpi_size page_size;
 102        int fd;
 103
 104        fd = open(SYSTEM_MEMORY, O_RDONLY | O_BINARY);
 105        if (fd < 0) {
 106                fprintf(stderr, "Cannot open %s\n", SYSTEM_MEMORY);
 107                return (NULL);
 108        }
 109
 110        /* Align the offset to use mmap */
 111
 112        page_size = acpi_os_get_page_size();
 113        offset = where % page_size;
 114
 115        /* Map the table header to get the length of the full table */
 116
 117        mapped_memory = mmap(NULL, (length + offset), PROT_READ, MMAP_FLAGS,
 118                             fd, (where - offset));
 119        if (mapped_memory == MAP_FAILED) {
 120                fprintf(stderr, "Cannot map %s\n", SYSTEM_MEMORY);
 121                close(fd);
 122                return (NULL);
 123        }
 124
 125        close(fd);
 126        return (ACPI_CAST8(mapped_memory + offset));
 127}
 128
 129/******************************************************************************
 130 *
 131 * FUNCTION:    acpi_os_unmap_memory
 132 *
 133 * PARAMETERS:  where               - Logical address of memory to be unmapped
 134 *              length              - How much memory to unmap
 135 *
 136 * RETURN:      None.
 137 *
 138 * DESCRIPTION: Delete a previously created mapping. Where and Length must
 139 *              correspond to a previous mapping exactly.
 140 *
 141 *****************************************************************************/
 142
 143void acpi_os_unmap_memory(void *where, acpi_size length)
 144{
 145        acpi_physical_address offset;
 146        acpi_size page_size;
 147
 148        page_size = acpi_os_get_page_size();
 149        offset = ACPI_TO_INTEGER(where) % page_size;
 150        munmap((u8 *)where - offset, (length + offset));
 151}
 152