aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/ia64/aliasing-test.c
blob: d23610fb2ff9e0560580bf4332bc81ea0a249326 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
/*
 * Exercise /dev/mem mmap cases that have been troublesome in the past
 *
 * (c) Copyright 2007 Hewlett-Packard Development Company, L.P.
 *	Bjorn Helgaas <bjorn.helgaas@hp.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#include <dirent.h>
#include <fcntl.h>
#include <fnmatch.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <unistd.h>
#include <linux/pci.h>

int sum;

int map_mem(char *path, off_t offset, size_t length, int touch)
{
	int fd, rc;
	void *addr;
	int *c;

	fd = open(path, O_RDWR);
	if (fd == -1) {
		perror(path);
		return -1;
	}

	if (fnmatch("/proc/bus/pci/*", path, 0) == 0) {
		rc = ioctl(fd, PCIIOC_MMAP_IS_MEM);
		if (rc == -1)
			perror("PCIIOC_MMAP_IS_MEM ioctl");
	}

	addr = mmap(NULL, length, PROT_READ|PROT_WRITE, MAP_SHARED, fd, offset);
	if (addr == MAP_FAILED)
		return 1;

	if (touch) {
		c = (int *) addr;
		while (c < (int *) (addr + length))
			sum += *c++;
	}

	rc = munmap(addr, length);
	if (rc == -1) {
		perror("munmap");
		return -1;
	}

	close(fd);
	return 0;
}

int scan_tree(char *path, char *file, off_t offset, size_t length, int touch)
{
	struct dirent **namelist;
	char *name, *path2;
	int i, n, r, rc = 0, result = 0;
	struct stat buf;

	n = scandir(path, &namelist, 0, alphasort);
	if (n < 0) {
		perror("scandir");
		return -1;
	}

	for (i = 0; i < n; i++) {
		name = namelist[i]->d_name;

		if (fnmatch(".", name, 0) == 0)
			goto skip;
		if (fnmatch("..", name, 0) == 0)
			goto skip;

		path2 = malloc(strlen(path) + strlen(name) + 3);
		strcpy(path2, path);
		strcat(path2, "/");
		strcat(path2, name);

		if (fnmatch(file, name, 0) == 0) {
			rc = map_mem(path2, offset, length, touch);
			if (rc == 0)
				fprintf(stderr, "PASS: %s 0x%lx-0x%lx is %s\n", path2, offset, offset + length, touch ? "readable" : "mappable");
			else if (rc > 0)
				fprintf(stderr, "PASS: %s 0x%lx-0x%lx not mappable\n", path2, offset, offset + length);
			else {
				fprintf(stderr, "FAIL: %s 0x%lx-0x%lx not accessible\n", path2, offset, offset + length);
				return rc;
			}
		} else {
			r = lstat(path2, &buf);
			if (r == 0 && S_ISDIR(buf.st_mode)) {
				rc = scan_tree(path2, file, offset, length, touch);
				if (rc < 0)
					return rc;
			}
		}

		result |= rc;
		free(path2);

skip:
		free(namelist[i]);
	}
	free(namelist);
	return result;
}

char buf[1024];

int read_rom(char *path)
{
	int fd, rc;
	size_t size = 0;

	fd = open(path, O_RDWR);
	if (fd == -1) {
		perror(path);
		return -1;
	}

	rc = write(fd, "1", 2);
	if (rc <= 0) {
		perror("write");
		return -1;
	}

	do {
		rc = read(fd, buf, sizeof(buf));
		if (rc > 0)
			size += rc;
	} while (rc > 0);

	close(fd);
	return size;
}

int scan_rom(char *path, char *file)
{
	struct dirent **namelist;
	char *name, *path2;
	int i, n, r, rc = 0, result = 0;
	struct stat buf;

	n = scandir(path, &namelist, 0, alphasort);
	if (n < 0) {
		perror("scandir");
		return -1;
	}

	for (i = 0; i < n; i++) {
		name = namelist[i]->d_name;

		if (fnmatch(".", name, 0) == 0)
			goto skip;
		if (fnmatch("..", name, 0) == 0)
			goto skip;

		path2 = malloc(strlen(path) + strlen(name) + 3);
		strcpy(path2, path);
		strcat(path2, "/");
		strcat(path2, name);

		if (fnmatch(file, name, 0) == 0) {
			rc = read_rom(path2);

			/*
			 * It's OK if the ROM is unreadable.  Maybe there
			 * is no ROM, or some other error ocurred.  The
			 * important thing is that no MCA happened.
			 */
			if (rc > 0)
				fprintf(stderr, "PASS: %s read %d bytes\n", path2, rc);
			else {
				fprintf(stderr, "PASS: %s not readable\n", path2);
				return rc;
			}
		} else {
			r = lstat(path2, &buf);
			if (r == 0 && S_ISDIR(buf.st_mode)) {
				rc = scan_rom(path2, file);
				if (rc < 0)
					return rc;
			}
		}

		result |= rc;
		free(path2);

skip:
		free(namelist[i]);
	}
	free(namelist);
	return result;
}

int main(void)
{
	int rc;

	if (map_mem("/dev/mem", 0, 0xA0000, 1) == 0)
		fprintf(stderr, "PASS: /dev/mem 0x0-0xa0000 is readable\n");
	else
		fprintf(stderr, "FAIL: /dev/mem 0x0-0xa0000 not accessible\n");

	/*
	 * It's not safe to blindly read the VGA frame buffer.  If you know
	 * how to poke the card the right way, it should respond, but it's
	 * not safe in general.  Many machines, e.g., Intel chipsets, cover
	 * up a non-responding card by just returning -1, but others will
	 * report the failure as a machine check.
	 */
	if (map_mem("/dev/mem", 0xA0000, 0x20000, 0) == 0)
		fprintf(stderr, "PASS: /dev/mem 0xa0000-0xc0000 is mappable\n");
	else
		fprintf(stderr, "FAIL: /dev/mem 0xa0000-0xc0000 not accessible\n");

	if (map_mem("/dev/mem", 0xC0000, 0x40000, 1) == 0)
		fprintf(stderr, "PASS: /dev/mem 0xc0000-0x100000 is readable\n");
	else
		fprintf(stderr, "FAIL: /dev/mem 0xc0000-0x100000 not accessible\n");

	/*
	 * Often you can map all the individual pieces above (0-0xA0000,
	 * 0xA0000-0xC0000, and 0xC0000-0x100000), but can't map the whole
	 * thing at once.  This is because the individual pieces use different
	 * attributes, and there's no single attribute supported over the
	 * whole region.
	 */
	rc = map_mem("/dev/mem", 0, 1024*1024, 0);
	if (rc == 0)
		fprintf(stderr, "PASS: /dev/mem 0x0-0x100000 is mappable\n");
	else if (rc > 0)
		fprintf(stderr, "PASS: /dev/mem 0x0-0x100000 not mappable\n");
	else
		fprintf(stderr, "FAIL: /dev/mem 0x0-0x100000 not accessible\n");

	scan_tree("/sys/class/pci_bus", "legacy_mem", 0, 0xA0000, 1);
	scan_tree("/sys/class/pci_bus", "legacy_mem", 0xA0000, 0x20000, 0);
	scan_tree("/sys/class/pci_bus", "legacy_mem", 0xC0000, 0x40000, 1);
	scan_tree("/sys/class/pci_bus", "legacy_mem", 0, 1024*1024, 0);

	scan_rom("/sys/devices", "rom");

	scan_tree("/proc/bus/pci", "??.?", 0, 0xA0000, 1);
	scan_tree("/proc/bus/pci", "??.?", 0xA0000, 0x20000, 0);
	scan_tree("/proc/bus/pci", "??.?", 0xC0000, 0x40000, 1);
	scan_tree("/proc/bus/pci", "??.?", 0, 1024*1024, 0);

	return rc;
}