1 // SPDX-License-Identifier: CDDL-1.0 2 /* 3 * CDDL HEADER START 4 * 5 * The contents of this file are subject to the terms of the 6 * Common Development and Distribution License (the "License"). 7 * You may not use this file except in compliance with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or https://opensource.org/licenses/CDDL-1.0. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 23 /* 24 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 25 * Use is subject to license terms. 26 */ 27 28 /* 29 * Assertion: 30 * 31 * A read operation and directory update operation performed 32 * concurrently on the same directory can lead to deadlock 33 * on a UFS logging file system, but not on a ZFS file system. 34 */ 35 36 #include <sys/types.h> 37 #include <sys/stat.h> 38 #include <errno.h> 39 #include <fcntl.h> 40 #include <string.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <unistd.h> 44 #define TMP_DIR /tmp 45 46 static char dirpath[256]; 47 48 int 49 main(int argc, char **argv) 50 { 51 const char *cp1 = ""; 52 int i = 0; 53 int ret = 0; 54 int testdd = 0; 55 pid_t pid; 56 static const int op_num = 5; 57 58 if (argc == 1) { 59 (void) printf("Usage: %s <mount point>\n", argv[0]); 60 exit(-1); 61 } 62 for (i = 0; i < 256; i++) { 63 dirpath[i] = 0; 64 } 65 66 cp1 = argv[1]; 67 if (strlen(cp1) >= (sizeof (dirpath) - strlen("/TMP_DIR"))) { 68 (void) printf("The string length of mount point is " 69 "too large\n"); 70 exit(-1); 71 } 72 (void) snprintf(dirpath, sizeof (dirpath), "%s/TMP_DIR", cp1); 73 74 ret = mkdir(dirpath, 0777); 75 if (ret != 0) { 76 if (errno != EEXIST) { 77 (void) printf("%s: mkdir(<%s>, 0777) failed: errno " 78 "(decimal)=%d\n", argv[0], dirpath, errno); 79 exit(-1); 80 } 81 } 82 testdd = open(dirpath, O_RDONLY|O_RSYNC|O_SYNC|O_DSYNC); 83 if (testdd < 0) { 84 (void) printf("%s: open(<%s>, O_RDONLY|O_RSYNC|O_SYNC|O_DSYNC)" 85 " failed: errno (decimal)=%d\n", argv[0], dirpath, errno); 86 exit(-1); 87 } else { 88 (void) close(testdd); 89 } 90 pid = fork(); 91 if (pid > 0) { 92 int fd = open(dirpath, O_RDONLY|O_RSYNC|O_SYNC|O_DSYNC); 93 char buf[16]; 94 int rdret; 95 int j = 0; 96 97 if (fd < 0) { 98 (void) printf("%s: open <%s> again failed:" 99 " errno = %d\n", argv[0], dirpath, errno); 100 exit(-1); 101 } 102 103 while (j < op_num) { 104 (void) sleep(1); 105 rdret = read(fd, buf, 16); 106 if (rdret == -1) { 107 (void) printf("readdir failed"); 108 } 109 j++; 110 } 111 (void) close(fd); 112 } else if (pid == 0) { 113 int fd = open(dirpath, O_RDONLY); 114 int chownret; 115 int k = 0; 116 117 if (fd < 0) { 118 (void) printf("%s: open(<%s>, O_RDONLY) again failed:" 119 " errno (decimal)=%d\n", argv[0], dirpath, errno); 120 exit(-1); 121 } 122 123 while (k < op_num) { 124 (void) sleep(1); 125 chownret = fchown(fd, 0, 0); 126 if (chownret == -1) { 127 (void) printf("chown failed"); 128 } 129 130 k++; 131 } 132 (void) close(fd); 133 } 134 135 return (0); 136 } 137