tests/zfs-tests/cmd/dir_rd_update/dir_rd_update.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 /*
  28  * Assertion:
  29  *
  30  *      A read operation and directory update operation performed
  31  *      concurrently on the same directory can lead to deadlock
  32  *      on a UFS logging file system, but not on a ZFS file system.
  33  */
  34
  35 #include <sys/types.h>
  36 #include <sys/stat.h>
  37 #include <errno.h>
  38 #include <fcntl.h>
  39 #include <string.h>
  40 #include <stdio.h>
  41 #include <stdlib.h>
  42 #include <unistd.h>
  43 #define TMP_DIR /tmp
  44
  45 static char dirpath[256];
  46
  47 int
  48 main(int argc, char **argv)
  49 {
  50         char *cp1 = "";
  51         int i = 0;
  52         int ret = 0;
  53         int testdd = 0;
  54         pid_t pid;
  55         static const int op_num = 5;
  56
  57         if (argc == 1) {
  58                 (void) printf("Usage: %s <mount point>\n", argv[0]);
  59                 exit(-1);
  60         }
  61         for (i = 0; i < 256; i++) {
  62                 dirpath[i] = 0;
  63         }
  64
  65         cp1 = argv[1];
  66         if (strlen(cp1) >= (sizeof (dirpath) - strlen("TMP_DIR"))) {
  67                 (void) printf("The string length of mount point is "
  68                     "too large\n");
  69                 exit(-1);
  70         }
  71         (void) strcpy(&dirpath[0], (const char *)cp1);
  72         (void) strcat(&dirpath[strlen(dirpath)], "TMP_DIR");
  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 }