xref: /freebsd/tools/regression/ufs/uprintf/ufs_uprintf.c (revision 0fca6ea1d4eea4c934cfff25ac9ee8ad6fe95583)
1 /*-
2  * Copyright (c) 2005 Robert N. M. Watson
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <err.h>
28 #include <errno.h>
29 #include <fcntl.h>
30 #include <limits.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <unistd.h>
35 
36 /*
37  * This regression test attempts to exercise two instances of uprintf(9) in
38  * UFS: (1) when blocks are exhausted, and (2) when inodes are exhausted, in
39  * order to attempt to trigger races in the uprintf(9) code.  The test
40  * accepts a pointer to a path -- ideally, a very small UFS partition -- and
41  * then proceeds to fill it in various ways.
42  *
43  * This tool assumes that it is alright to create, and delete, entries in the
44  * directory with names of integer values.  Don't run this tool against a
45  * directory that has files with names along those lines if you want to keep
46  * the files.
47  *
48  * Suggested usage is:
49  *
50  * mdconfig -a -t malloc -s 512
51  * newfs /dev/mdX
52  * mount /dev/mdX /mnt
53  * ufs_uprintf /mnt
54  * umount /mnt
55  * mdconfig -d -u X
56  */
57 
58 #define	NUMTRIES	200
59 
60 /*
61  * Fill up the disk, then generate NUMTRIES additional ENOSPC errors.
62  */
63 #define	BLOCKSIZE	1024
64 #define	BLOCKS_FILENAME	"0"
65 static void
66 fill_blocks(void)
67 {
68 	char block[BLOCKSIZE];
69 	ssize_t len;
70 	int fd, i;
71 
72 	fd = open(BLOCKS_FILENAME, O_CREAT | O_TRUNC | O_RDWR, 0600);
73 	if (fd < 0)
74 		err(-1, "fill_blocks: open(%s)", BLOCKS_FILENAME);
75 
76 	/*
77 	 * First step: fill the disk device.  Keep extending the file until
78 	 * we hit our first error, and hope it is ENOSPC.
79 	 */
80 	bzero(block, BLOCKSIZE);
81 	errno = 0;
82 	while (1) {
83 		len = write(fd, block, BLOCKSIZE);
84 		if (len < 0)
85 			break;
86 		if (len != BLOCKSIZE) {
87 			warnx("fill_blocks: write(%d) returned %zd",
88 			    BLOCKSIZE, len);
89 			close(fd);
90 			(void)unlink(BLOCKS_FILENAME);
91 			exit(-1);
92 		}
93 
94 	}
95 	if (errno != ENOSPC) {
96 		warn("fill_blocks: write");
97 		close(fd);
98 		(void)unlink(BLOCKS_FILENAME);
99 		exit(-1);
100 	}
101 
102 	/*
103 	 * Second step: generate NUMTRIES instances of the error by retrying
104 	 * the write.
105 	 */
106 	for (i = 0; i < NUMTRIES; i++) {
107 		len = write(fd, block, BLOCKSIZE);
108 		if (len < 0 && errno != ENOSPC) {
109 			warn("fill_blocks: write after ENOSPC");
110 			close(fd);
111 			(void)unlink(BLOCKS_FILENAME);
112 			exit(-1);
113 		}
114 	}
115 
116 	close(fd);
117 	(void)unlink(BLOCKS_FILENAME);
118 }
119 
120 /*
121  * Create as many entries in the directory as we can, then once we start
122  * hitting ENOSPC, try NUMTRIES additional times.  Note that we don't be able
123  * to tell the difference between running out of inodes and running out of
124  * room to extend the directory, so this is just a best effort.
125  */
126 static void
127 fill_inodes(void)
128 {
129 	char path[PATH_MAX];
130 	int fd, i, max;
131 
132 	/*
133 	 * First step, fill the directory.
134 	 */
135 	i = 0;
136 	while (1) {
137 		snprintf(path, PATH_MAX, "%d", i);
138 		fd = open(path, O_CREAT | O_TRUNC | O_RDWR, 0600);
139 		if (fd < 0)
140 			break;
141 		close(fd);
142 		i++;
143 	}
144 	max = i;
145 	if (errno != ENOSPC) {
146 		warn("fill_inodes: open(%s)", path);
147 		goto teardown;
148 	}
149 
150 	for (i = 0; i < NUMTRIES; i++) {
151 		fd = open(path, O_CREAT | O_TRUNC | O_RDWR, 0600);
152 		if (fd < 0 && errno != ENOSPC) {
153 			warn("fill_inodes: open(%s) after ENOSPC", path);
154 			goto teardown;
155 		}
156 		if (fd >= 0) {
157 			warnx("fill_inodes: open(%s) after ENOSPC returned "
158 			    " %d", path, fd);
159 			close(fd);
160 			goto teardown;
161 		}
162 	}
163 
164 teardown:
165 	for (i = 0; i < max; i++) {
166 		snprintf(path, PATH_MAX, "%d", i);
167 		(void)unlink(path);
168 	}
169 }
170 
171 int
172 main(int argc, char *argv[])
173 {
174 
175 	if (argc != 2)
176 		err(-1, "usage: ufs_uprintf /non_optional_path");
177 
178 	if (chdir(argv[1]) < 0)
179 		err(-1, "chdir(%s)", argv[1]);
180 
181 	fill_blocks();
182 
183 	fill_inodes();
184 
185 	return (0);
186 }
187