freebsd-dev/tools/regression/ufs/uprintf/ufs_uprintf.c
Robert Watson 5334bbba91 Small regression test tool to generate two forms of ENOSPC on a file
system: out of blocks, and out of inodes.  Useful for exercising the
uprintf(9) calls in UFS/ext2fs in order to detect races.
2005-09-19 16:29:36 +00:00

189 lines
4.7 KiB
C

/*-
* Copyright (c) 2005 Robert N. M. Watson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
/*
* This regression test attempts to exercise two instances of uprintf(9) in
* UFS: (1) when blocks are exhausted, and (2) when inodes are exhausted, in
* order to attempt to trigger races in the uprintf(9) code. The test
* accepts a pointer to a path -- ideally, a very small UFS partition -- and
* then proceeds to fill it in various ways.
*
* This tool assumes that it is alright to create, and delete, entries in the
* directory with names of integer values. Don't run this tool against a
* directory that has files with names along those lines if you want to keep
* the files.
*
* Suggested usage is:
*
* mdconfig -a -t malloc -s 512
* newfs /dev/mdX
* mount /dev/mdX /mnt
* ufs_uprintf /mnt
* umount /mnt
* mdconfig -d -u X
*/
#define NUMTRIES 200
/*
* Fill up the disk, then generate NUMTRIES additional ENOSPC errors.
*/
#define BLOCKSIZE 1024
#define BLOCKS_FILENAME "0"
static void
fill_blocks(void)
{
char block[BLOCKSIZE];
ssize_t len;
int fd, i;
fd = open(BLOCKS_FILENAME, O_CREAT | O_TRUNC | O_RDWR, 0600);
if (fd < 0)
err(-1, "fill_blocks: open(%s)", BLOCKS_FILENAME);
/*
* First step: fill the disk device. Keep extending the file until
* we hit our first error, and hope it is ENOSPC.
*/
bzero(block, BLOCKSIZE);
errno = 0;
while (1) {
len = write(fd, block, BLOCKSIZE);
if (len < 0)
break;
if (len != BLOCKSIZE) {
warnx("fill_blocks: write(%d) returned %d",
BLOCKSIZE, len);
close(fd);
(void)unlink(BLOCKS_FILENAME);
exit(-1);
}
}
if (errno != ENOSPC) {
warn("fill_blocks: write");
close(fd);
(void)unlink(BLOCKS_FILENAME);
exit(-1);
}
/*
* Second step: generate NUMTRIES instances of the error by retrying
* the write.
*/
for (i = 0; i < NUMTRIES; i++) {
len = write(fd, block, BLOCKSIZE);
if (len < 0 && errno != ENOSPC) {
warn("fill_blocks: write after ENOSPC");
close(fd);
(void)unlink(BLOCKS_FILENAME);
exit(-1);
}
}
close(fd);
(void)unlink(BLOCKS_FILENAME);
}
/*
* Create as many entries in the directory as we can, then once we start
* hitting ENOSPC, try NUMTRIES additional times. Note that we don't be able
* to tell the difference between running out of inodes and running out of
* room to extend the directory, so this is just a best effort.
*/
static void
fill_inodes(void)
{
char path[PATH_MAX];
int fd, i, max;
/*
* First step, fill the directory.
*/
i = 0;
while (1) {
snprintf(path, PATH_MAX, "%d", i);
fd = open(path, O_CREAT | O_TRUNC | O_RDWR, 0600);
if (fd < 0)
break;
close(fd);
i++;
}
max = i;
if (errno != ENOSPC) {
warn("fill_inodes: open(%s)", path);
goto teardown;
}
for (i = 0; i < NUMTRIES; i++) {
fd = open(path, O_CREAT | O_TRUNC | O_RDWR, 0600);
if (fd < 0 && errno != ENOSPC) {
warn("fill_inodes: open(%s) after ENOSPC", path);
goto teardown;
}
if (fd >= 0) {
warnx("fill_inodes: open(%s) after ENOSPC returned "
" %d", path, fd);
close(fd);
goto teardown;
}
}
teardown:
for (i = 0; i < max; i++) {
snprintf(path, PATH_MAX, "%d", i);
(void)unlink(path);
}
}
int
main(int argc, char *argv[])
{
if (argc != 2)
err(-1, "usage: ufs_uprintf /non_optional_path");
if (chdir(argv[1]) < 0)
err(-1, "chdir(%s)", argv[1]);
fill_blocks();
fill_inodes();
return (0);
}