1 files changed, 138 insertions, 0 deletions
diff --git a/sys/contrib/openzfs/tests/zfs-tests/cmd/readmmap/readmmap.c b/sys/contrib/openzfs/tests/zfs-tests/cmd/readmmap/readmmap.c
new file mode 100644
index 000000000000..e21c2c867d9a
--- /dev/null
+++ b/sys/contrib/openzfs/tests/zfs-tests/cmd/readmmap/readmmap.c
@@ -0,0 +1,138 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+/*
+ * --------------------------------------------------------------
+ *	BugId 5047993 : Getting bad read data.
+ *
+ *	Usage: readmmap <filename>
+ *
+ *	where:
+ *		filename is an absolute path to the file name.
+ *
+ *	Return values:
+ *		1 : error
+ *		0 : no errors
+ * --------------------------------------------------------------
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <sys/mman.h>
+#include <time.h>
+
+int
+main(int argc, char **argv)
+{
+	char *filename = "badfile";
+	size_t size = 4395;
+	size_t idx = 0;
+	char *buf = NULL;
+	char *map = NULL;
+	int fd = -1, bytes, retval = 0;
+	unsigned seed;
+
+	if (argc < 2 || optind == argc) {
+		(void) fprintf(stderr,
+		    "usage: %s <file name>\n", argv[0]);
+		exit(1);
+	}
+
+	if ((buf = calloc(1, size)) == NULL) {
+		perror("calloc");
+		exit(1);
+	}
+
+	filename = argv[optind];
+
+	(void) remove(filename);
+
+	fd = open(filename, O_RDWR|O_CREAT|O_TRUNC, 0666);
+	if (fd == -1) {
+		perror("open to create");
+		retval = 1;
+		goto end;
+	}
+
+	bytes = write(fd, buf, size);
+	if (bytes != size) {
+		(void) printf("short write: %d != %zd\n", bytes, size);
+		retval = 1;
+		goto end;
+	}
+
+	map = mmap(0, size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+	if (map == MAP_FAILED) {
+		perror("mmap");
+		retval = 1;
+		goto end;
+	}
+	seed = time(NULL);
+	srandom(seed);
+
+	idx = random() % size;
+	map[idx] = 1;
+
+	if (msync(map, size, MS_SYNC) != 0) {
+		perror("msync");
+		retval = 1;
+		goto end;
+	}
+
+	if (munmap(map, size) != 0) {
+		perror("munmap");
+		retval = 1;
+		goto end;
+	}
+
+	bytes = pread(fd, buf, size, 0);
+	if (bytes != size) {
+		(void) printf("short read: %d != %zd\n", bytes, size);
+		retval = 1;
+		goto end;
+	}
+
+	if (buf[idx] != 1) {
+		(void) printf(
+		    "bad data from read!  got buf[%zd]=%d, expected 1\n",
+		    idx, buf[idx]);
+		retval = 1;
+		goto end;
+	}
+
+	(void) printf("good data from read: buf[%zd]=1\n", idx);
+end:
+	if (fd != -1) {
+		(void) close(fd);
+	}
+	if (buf != NULL) {
+		free(buf);
+	}
+
+	return (retval);
+}