1 files changed, 97 insertions, 0 deletions
diff --git a/tests/zfs-tests/cmd/mmapwrite/mmapwrite.c b/tests/zfs-tests/cmd/mmapwrite/mmapwrite.c
new file mode 100644
index 000000000000..2eca124696e0
--- /dev/null
+++ b/tests/zfs-tests/cmd/mmapwrite/mmapwrite.c
@@ -0,0 +1,97 @@
+/*
+ * 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.
+ */
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/mman.h>
+#include <pthread.h>
+
+/*
+ * --------------------------------------------------------------------
+ * Bug Id: 5032643
+ *
+ * Simply writing to a file and mmaping that file at the same time can
+ * result in deadlock.  Nothing perverse like writing from the file's
+ * own mapping is required.
+ * --------------------------------------------------------------------
+ */
+
+static void *
+mapper(void *fdp)
+{
+	void *addr;
+	int fd = *(int *)fdp;
+
+	if ((addr =
+	    mmap(0, 8192, PROT_READ, MAP_SHARED, fd, 0)) == MAP_FAILED) {
+		perror("mmap");
+		exit(1);
+	}
+	for (;;) {
+		if (mmap(addr, 8192, PROT_READ,
+		    MAP_SHARED|MAP_FIXED, fd, 0) == MAP_FAILED) {
+			perror("mmap");
+			exit(1);
+		}
+	}
+	/* NOTREACHED */
+	return ((void *)1);
+}
+
+int
+main(int argc, char **argv)
+{
+	int fd;
+	char buf[BUFSIZ];
+	pthread_t tid;
+
+	if (argc != 2) {
+		(void) printf("usage: %s <file name>\n", argv[0]);
+		exit(1);
+	}
+
+	if ((fd = open(argv[1], O_RDWR|O_CREAT|O_TRUNC, 0666)) == -1) {
+		perror("open");
+		exit(1);
+	}
+
+	(void) pthread_setconcurrency(2);
+	if (pthread_create(&tid, NULL, mapper, &fd) != 0) {
+		perror("pthread_create");
+		exit(1);
+	}
+	for (;;) {
+		if (write(fd, buf, sizeof (buf)) == -1) {
+			perror("write");
+			exit(1);
+		}
+	}
+
+	/* NOTREACHED */
+	return (0);
+}