From f7b47c58e87caf91e1648b3c0fa348c555595800 Mon Sep 17 00:00:00 2001
From: Sun Ke <sunke32@huawei.com>
Date: Mon, 23 Dec 2019 11:18:29 +0800
Subject: [PATCH] nbd/003:add mount and clear_sock test for nbd

Add the test case to check nbd device. This test case catches regressions
fixed by commit 92b5c8f0063e4 "nbd: replace kill_bdev() with
__invalidate_device() again".

Establish the nbd connection. Run two processes. The first one do mount
and umount, and the other one do clear_sock ioctl.

Signed-off-by: Sun Ke <sunke32@huawei.com>
[Omar: simplify]
Signed-off-by: Omar Sandoval <osandov@fb.com>
---
 src/.gitignore         |  3 +-
 src/Makefile           |  5 ++-
 src/mount_clear_sock.c | 91 ++++++++++++++++++++++++++++++++++++++++++
 tests/nbd/003          | 30 ++++++++++++++
 tests/nbd/003.out      |  1 +
 5 files changed, 127 insertions(+), 3 deletions(-)
 create mode 100644 src/mount_clear_sock.c
 create mode 100644 tests/nbd/003
 create mode 100644 tests/nbd/003.out

diff --git a/src/.gitignore b/src/.gitignore
index 2108f56..355bed3 100644
--- a/src/.gitignore
+++ b/src/.gitignore
@@ -2,8 +2,9 @@
 /loblksize
 /loop_change_fd
 /loop_get_status_null
-/openclose
+/mount_clear_sock
 /nbdsetsize
+/openclose
 /sg/dxfer-from-dev
 /sg/syzkaller1
 /zbdioctl
diff --git a/src/Makefile b/src/Makefile
index 917d6f4..3b587f6 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -4,12 +4,13 @@ HAVE_C_HEADER = $(shell if echo "\#include <$(1)>" |		\
 
 C_TARGETS := \
 	loblksize \
+	loop_change_fd \
 	loop_get_status_null \
+	mount_clear_sock \
+	nbdsetsize \
 	openclose \
 	sg/dxfer-from-dev \
 	sg/syzkaller1 \
-	nbdsetsize \
-	loop_change_fd \
 	zbdioctl
 
 CXX_TARGETS := \
diff --git a/src/mount_clear_sock.c b/src/mount_clear_sock.c
new file mode 100644
index 0000000..4030a4a
--- /dev/null
+++ b/src/mount_clear_sock.c
@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: GPL-3.0+
+// Copyright (C) 2019 Sun Ke
+
+#include <assert.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <linux/fs.h>
+#include <linux/nbd.h>
+
+int main(int argc, char **argv)
+{
+	const char *mountpoint, *dev, *fstype;
+	int loops, fd;
+
+	if (argc != 5) {
+		fprintf(stderr, "usage: %s DEV MOUNTPOINT FSTYPE LOOPS", argv[0]);
+		return EXIT_FAILURE;
+	}
+
+	dev = argv[1];
+	mountpoint = argv[2];
+	fstype = argv[3];
+	loops = atoi(argv[4]);
+
+	fd = open(dev, O_RDWR);
+	if (fd == -1) {
+		perror("open");
+		return EXIT_FAILURE;
+	}
+
+	for (int i = 0; i < loops; i++) {
+		pid_t mount_pid, clear_sock_pid;
+		int wstatus;
+
+		mount_pid = fork();
+		if (mount_pid == -1) {
+			perror("fork");
+			return EXIT_FAILURE;
+		}
+		if (mount_pid == 0) {
+			mount(dev, mountpoint, fstype,
+			      MS_NOSUID | MS_SYNCHRONOUS, 0);
+			umount(mountpoint);
+			exit(EXIT_SUCCESS);
+		}
+
+		clear_sock_pid = fork();
+		if (clear_sock_pid == -1) {
+			perror("fork");
+			return EXIT_FAILURE;
+		}
+		if (clear_sock_pid == 0) {
+			if (ioctl(fd, NBD_CLEAR_SOCK, 0) == -1) {
+				perror("ioctl");
+				exit(EXIT_FAILURE);
+			}
+			exit(EXIT_SUCCESS);
+		}
+
+		if (waitpid(mount_pid, &wstatus, 0) == -1) {
+			perror("waitpid");
+			return EXIT_FAILURE;
+		}
+		if (!WIFEXITED(wstatus) ||
+		    WEXITSTATUS(wstatus) != EXIT_SUCCESS) {
+			fprintf(stderr, "mount process failed");
+			return EXIT_FAILURE;
+		}
+
+		if (waitpid(clear_sock_pid, &wstatus, 0) == -1) {
+			perror("waitpid");
+			return EXIT_FAILURE;
+		}
+		if (!WIFEXITED(wstatus) ||
+		    WEXITSTATUS(wstatus) != EXIT_SUCCESS) {
+			fprintf(stderr, "NBD_CLEAR_SOCK process failed");
+			return EXIT_FAILURE;
+		}
+	}
+
+	close(fd);
+	return EXIT_SUCCESS;
+}
diff --git a/tests/nbd/003 b/tests/nbd/003
new file mode 100644
index 0000000..57fb63a
--- /dev/null
+++ b/tests/nbd/003
@@ -0,0 +1,30 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-3.0+
+# Copyright (C) 2019 Sun Ke
+#
+# Regression test for commit 2b5c8f0063e4 ("nbd: replace kill_bdev() with
+# __invalidate_device() again").
+
+. tests/nbd/rc
+
+DESCRIPTION="mount/unmount concurrently with NBD_CLEAR_SOCK"
+QUICK=1
+
+requires() {
+	_have_nbd && _have_src_program mount_clear_sock
+}
+
+test() {
+	echo "Running ${TEST_NAME}"
+
+	_start_nbd_server
+	nbd-client -L -N export localhost /dev/nbd0 >> "$FULL" 2>&1
+	mkfs.ext4 /dev/nbd0 >> "$FULL" 2>&1
+
+	mkdir -p "${TMPDIR}/mnt"
+	src/mount_clear_sock /dev/nbd0 "${TMPDIR}/mnt" ext4 5000
+	umount "${TMPDIR}/mnt" > /dev/null 2>&1
+
+	nbd-client -d /dev/nbd0 >> "$FULL" 2>&1
+	_stop_nbd_server
+}
diff --git a/tests/nbd/003.out b/tests/nbd/003.out
new file mode 100644
index 0000000..aa340db
--- /dev/null
+++ b/tests/nbd/003.out
@@ -0,0 +1 @@
+Running nbd/003
-- 
2.49.0