fusefs: fix intermittency in some ENOENT tests

When a FUSE operation other than LOOKUP returns ENOENT, the kernel will
reclaim that vnode, resuling in a FUSE_FORGET being sent a short while
later.  Many of the ENOENT tests weren't expecting those FUSE_FORGET
operations.  They usually passed by luck since FUSE_FORGET is often delayed.
This commit adds appropriate expectations.

MFC after:	2 weeks

3 files changed, 35 insertions, 0 deletions

diff --git a/tests/sys/fs/fusefs/getattr.cc b/tests/sys/fs/fusefs/getattr.cc
index 4c7ab543ab7e..fb91f8c049d0 100644
--- a/tests/sys/fs/fusefs/getattr.cc
+++ b/tests/sys/fs/fusefs/getattr.cc
@@ -32,6 +32,8 @@
 
 extern "C" {
 #include <sys/param.h>
+
+#include <semaphore.h>
 }
 
 #include "mockfs.hh"
@@ -172,6 +174,9 @@ TEST_F(Getattr, enoent)
 	const char RELPATH[] = "some_file.txt";
 	struct stat sb;
 	const uint64_t ino = 42;
+	sem_t sem;
+
+	ASSERT_EQ(0, sem_init(&sem, 0, 0)) << strerror(errno);
 
 	expect_lookup(RELPATH, ino, S_IFREG | 0644, 0, 1, 0, 0);
 	EXPECT_CALL(*m_mock, process(
@@ -181,8 +186,15 @@ TEST_F(Getattr, enoent)
 		}, Eq(true)),
 		_)
 	).WillOnce(Invoke(ReturnErrno(ENOENT)));
+	// Since FUSE_GETATTR returns ENOENT, the kernel will reclaim the vnode
+	// and send a FUSE_FORGET
+	expect_forget(ino, 1, &sem);
+
 	EXPECT_NE(0, stat(FULLPATH, &sb));
 	EXPECT_EQ(ENOENT, errno);
+
+	sem_wait(&sem);
+	sem_destroy(&sem);
 }
 
 TEST_F(Getattr, ok)
diff --git a/tests/sys/fs/fusefs/open.cc b/tests/sys/fs/fusefs/open.cc
index 8aef5bedf2ec..430c78041128 100644
--- a/tests/sys/fs/fusefs/open.cc
+++ b/tests/sys/fs/fusefs/open.cc
@@ -32,7 +32,9 @@
 
 extern "C" {
 #include <sys/wait.h>
+
 #include <fcntl.h>
+#include <semaphore.h>
 }
 
 #include "mockfs.hh"
@@ -105,6 +107,9 @@ TEST_F(Open, enoent)
 	const char FULLPATH[] = "mountpoint/some_file.txt";
 	const char RELPATH[] = "some_file.txt";
 	uint64_t ino = 42;
+	sem_t sem;
+
+	ASSERT_EQ(0, sem_init(&sem, 0, 0)) << strerror(errno);
 
 	expect_lookup(RELPATH, ino, S_IFREG | 0644, 0, 1);
 	EXPECT_CALL(*m_mock, process(
@@ -114,8 +119,15 @@ TEST_F(Open, enoent)
 		}, Eq(true)),
 		_)
 	).WillOnce(Invoke(ReturnErrno(ENOENT)));
+	// Since FUSE_OPEN returns ENOENT, the kernel will reclaim the vnode
+	// and send a FUSE_FORGET
+	expect_forget(ino, 1, &sem);
+
 	ASSERT_EQ(-1, open(FULLPATH, O_RDONLY));
 	EXPECT_EQ(ENOENT, errno);
+
+	sem_wait(&sem);
+	sem_destroy(&sem);
 }
 
 /* 
diff --git a/tests/sys/fs/fusefs/opendir.cc b/tests/sys/fs/fusefs/opendir.cc
index d59feb63fd67..a50e679f0add 100644
--- a/tests/sys/fs/fusefs/opendir.cc
+++ b/tests/sys/fs/fusefs/opendir.cc
@@ -32,7 +32,9 @@
 
 extern "C" {
 #include <dirent.h>
+
 #include <fcntl.h>
+#include <semaphore.h>
 }
 
 #include "mockfs.hh"
@@ -82,12 +84,21 @@ TEST_F(Opendir, enoent)
 	const char FULLPATH[] = "mountpoint/some_dir";
 	const char RELPATH[] = "some_dir";
 	uint64_t ino = 42;
+	sem_t sem;
+
+	ASSERT_EQ(0, sem_init(&sem, 0, 0)) << strerror(errno);
 
 	expect_lookup(RELPATH, ino);
 	expect_opendir(ino, O_RDONLY, ReturnErrno(ENOENT));
+	// Since FUSE_OPENDIR returns ENOENT, the kernel will reclaim the vnode
+	// and send a FUSE_FORGET
+	expect_forget(ino, 1, &sem);
 
 	ASSERT_EQ(-1, open(FULLPATH, O_DIRECTORY));
 	EXPECT_EQ(ENOENT, errno);
+
+	sem_wait(&sem);
+	sem_destroy(&sem);
 }
 
 /*