1/******************************************************************************
2 *
3 * Module Name: osunixmap - Unix OSL for file mappings
4 *
5 *****************************************************************************/
6
7/*
8 * Copyright (C) 2000 - 2015, 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#ifdef _free_BSD
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