1#!/bin/sh 2 3# 4# Copyright (c) 2016 EMC Corp. 5# All rights reserved. 6# 7# Redistribution and use in source and binary forms, with or without 8# modification, are permitted provided that the following conditions 9# are met: 10# 1. Redistributions of source code must retain the above copyright 11# notice, this list of conditions and the following disclaimer. 12# 2. Redistributions in binary form must reproduce the above copyright 13# notice, this list of conditions and the following disclaimer in the 14# documentation and/or other materials provided with the distribution. 15# 16# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26# SUCH DAMAGE. 27# 28 29# fcntl(2) locking scenario, using UFS and a nullfs mount. 30# No problems seen. 31 32[ `id -u ` -ne 0 ] && echo "Must be root!" && exit 1 33 34. ../default.cfg 35 36here=`pwd` 37cd /tmp 38sed '1,/^EOF/d' < $here/$0 > nullfs22.c 39mycc -o nullfs22 -Wall -Wextra -O0 -g nullfs22.c || exit 1 40rm -f nullfs22.c 41 42mp2=${mntpoint}2 43[ -d $mp2 ] || mkdir -p $mp2 44mount | grep -q "on $mp2 " && umount $mp2 45mount | grep "on $mntpoint " | grep -q /dev/md && umount -f $mntpoint 46[ -c /dev/md$mdstart ] && mdconfig -d -u $mdstart 47mdconfig -a -t swap -s 512m -u $mdstart || exit 1 48newfs -n md$mdstart > /dev/null 49mount /dev/md$mdstart $mntpoint 50 51mount -t nullfs $mntpoint $mp2 52 53/tmp/nullfs22 $mntpoint $mp2 54status=$? 55 56while mount | grep -q "on $mp2 "; do 57 umount $mp2 58done 59while mount | grep "on $mntpoint " | grep -q /dev/md; do 60 umount $mntpoint || sleep 1 61done 62mdconfig -d -u $mdstart 63rm -f /tmp/nullfs22 64exit $status 65EOF 66#include <sys/param.h> 67#include <sys/mman.h> 68#include <sys/wait.h> 69 70#include <machine/atomic.h> 71 72#include <err.h> 73#include <errno.h> 74#include <fcntl.h> 75#include <signal.h> 76#include <stdio.h> 77#include <stdlib.h> 78#include <string.h> 79#include <unistd.h> 80 81#define LOOPS 1024 82#define N (512) 83#define PARALLEL 4 84 85#define DONE 1 86#define SYNC 0 87 88int fd; 89volatile u_int *share; 90char name1[80], name2[80]; 91 92static void 93ahandler(int s __unused) 94{ 95 fprintf(stderr, "In alarm handler\n"); 96 unlink(name1); 97 _exit(1); 98} 99 100void 101add(int n, int increment) 102{ 103 struct flock fl; 104 off_t pos; 105 long val, oval __unused; 106 int r; 107 108 pos = n * sizeof(val); 109 memset(&fl, 0, sizeof(fl)); 110 fl.l_start = pos; 111 fl.l_len = sizeof(val); 112 fl.l_type = F_WRLCK; 113 fl.l_whence = SEEK_SET; 114 115 while (fcntl(fd, F_SETLKW, &fl) < 0) { 116 if (errno != EAGAIN) 117 err(1, "F_SETLKW (child)"); 118 usleep(100); 119 } 120 121 if (lseek(fd, pos, SEEK_SET) == -1) 122 err(1, "lseek"); 123 oval = 999999; 124 while ((r = read(fd, &val, sizeof(val)) != sizeof(val))) { 125 if (r == -1 && errno != EAGAIN) 126 err(1, "read"); 127 if (lseek(fd, pos, SEEK_SET) == -1) 128 err(1, "lseek"); 129 } 130 oval = val; 131 val = val + increment; 132#if defined(DEBUG) 133 fprintf(stderr, "add(%d, %d) @ pos %ld: %ld = %ld + %d\n", 134 n, increment, (long)pos, val, oval, increment); 135#endif 136 if (lseek(fd, pos, SEEK_SET) == -1) 137 err(1, "lseek"); 138 while ((r = write(fd, &val, sizeof(val)) != sizeof(val))) { 139 if (r == -1 && errno != EAGAIN) 140 err(1, "write"); 141 if (lseek(fd, pos, SEEK_SET) == -1) 142 err(1, "lseek"); 143 } 144 145 fl.l_type = F_UNLCK; 146 if (fcntl(fd, F_SETLK, &fl) < 0) 147 err(1, "F_UNLCK"); 148 149} 150 151void 152count(int val) 153{ 154 int i, j; 155 char help[80], *name; 156 157 if (val == 1) 158 name = name1; 159 else 160 name = name2; 161 snprintf(help, sizeof(help), "%s %d %s", __func__, val, name); 162 setproctitle("%s", help); 163 atomic_add_int(&share[SYNC], 1); 164 while (share[SYNC] != 2 * PARALLEL) 165 ; 166 167 /* Need to re-open after a fork() */ 168 close(fd); 169 if ((fd = open(name, O_RDWR)) == -1) 170 err(1, "open(%s)", name); 171 172 for (i = 0; i < LOOPS; i++) { 173 for (j = 0; j < N; j++) 174 add(j, val); 175 } 176 177 atomic_add_int(&share[DONE], 1); 178 179 _exit(0); 180} 181 182int 183main(int argc, char *argv[]) 184{ 185 off_t len; 186 size_t mlen; 187 long val, sum; 188 int i, s, stat; 189 190 if (argc != 3) { 191 fprintf(stderr, "Usage: %s <dir1> <dir2>\n", argv[0]); 192 exit(1); 193 } 194 195 mlen = PAGE_SIZE; 196 if ((share = mmap(NULL, mlen, PROT_READ | PROT_WRITE, 197 MAP_ANON | MAP_SHARED, -1, 0)) == MAP_FAILED) 198 err(1, "mmap"); 199 snprintf(name1, sizeof(name1), "%s/work", argv[1]); 200 snprintf(name2, sizeof(name2), "%s/work", argv[2]); 201 signal(SIGALRM, ahandler); 202 alarm(300); 203 if ((fd = open(name1, O_RDWR | O_CREAT | O_TRUNC, 0640)) == -1) 204 err(1, "open(%s)", name1); 205 len = N * sizeof(val); 206 if (ftruncate(fd, len) == -1) 207 err(1, "ftruncate"); 208 209 for (i = 0; i < PARALLEL; i++) { 210 if (fork() == 0) 211 count(1); 212 } 213 for (i = 0; i < PARALLEL; i++) { 214 if (fork() == 0) 215 count(-1); 216 } 217 218 while (share[DONE] != 2 * PARALLEL) 219 usleep(10000); 220 221 if (lseek(fd, 0, SEEK_SET) == -1) 222 err(1, "lseek"); 223 sum = 0; 224 for (i = 0; i < N; i++) { 225 if (read(fd, &val, sizeof(val)) != sizeof(val)) 226 err(1, "Final read"); 227 if (val != 0) 228 fprintf(stderr, "index %d: %ld\n", i, val); 229 sum += val; 230 } 231 if (sum != 0) 232 fprintf(stderr, "FAIL\n"); 233 unlink(name1); 234 235 s = 0; 236 for (i = 0; i < PARALLEL; i++) { 237 wait(&stat); 238 s += WEXITSTATUS(stat); 239 wait(&stat); 240 s += WEXITSTATUS(stat); 241 } 242 243 close(fd); 244 245 return (sum != 0 || s != 0); 246} 247