testing: skip tarfs tests if module is not loadable.

Approved by:	asomers
Sponsored by:	Netflix
Differential Revision:	https://reviews.freebsd.org/D38828

tests/sys/fs/tarfs/tarfs_test.sh

@@ -38,6 +38,7 @@ tarfs_basic_head() {
 	atf_set "require.user" "root"
 }
 tarfs_basic_body() {
+	kldload -n tarfs || atf_skip "This test requires tarfs and could not load it"
 	mkdir "${mnt}"
 	"${mktar}" tarfs_test.tar.zst
 	atf_check mount -rt tarfs tarfs_test.tar.zst "${mnt}"
@@ -47,7 +48,7 @@ tarfs_basic_body() {
 	atf_check_equal "$(sha256 -q "${mnt}"/sparse_file)" ${sum}
 }
 tarfs_basic_cleanup() {
-	umount "${mnt}"
+	umount "${mnt}" || true
 }
 
 atf_test_case tarfs_notdir_device cleanup
@@ -56,6 +57,7 @@ tarfs_notdir_device_head() {
 	atf_set "require.user" "root"
 }
 tarfs_notdir_device_body() {
+	kldload -n tarfs || atf_skip "This test requires tarfs and could not load it"
 	mkdir "${mnt}"
 	atf_check mknod d b 0xdead 0xbeef
 	tar cf tarfs_notdir.tar d
@@ -76,6 +78,7 @@ tarfs_notdir_dot_head() {
 	atf_set "require.user" "root"
 }
 tarfs_notdir_dot_body() {
+	kldload -n tarfs || atf_skip "This test requires tarfs and could not load it"
 	mkdir "${mnt}"
 	echo "hello" >d
 	tar cf tarfs_notdir.tar d
@@ -96,6 +99,7 @@ tarfs_notdir_dotdot_head() {
 	atf_set "require.user" "root"
 }
 tarfs_notdir_dotdot_body() {
+	kldload -n tarfs || atf_skip "This test requires tarfs and could not load it"
 	mkdir "${mnt}"
 	echo "hello" >d
 	tar cf tarfs_notdir.tar d
@@ -116,6 +120,7 @@ tarfs_notdir_file_head() {
 	atf_set "require.user" "root"
 }
 tarfs_notdir_file_body() {
+	kldload -n tarfs || atf_skip "This test requires tarfs and could not load it"
 	mkdir "${mnt}"
 	echo "hello" >d
 	tar cf tarfs_notdir.tar d