[PATCH 08/10] selftests/filesystems/overlayfs: fix set_layers_via_fds link error

set_layers_via_fds.c calls open_tree() directly, but that wrapper is
not provided by all C libraries, so the test fails to link with
"undefined reference to open_tree" on toolchains without it.

Use sys_open_tree() from ../wrappers.h, the syscall wrapper already
used for move_mount(), fsmount() and friends here.  This is also a
prerequisite for building the new idmapped_mounts test added to this
directory.

Signed-off-by: Christian Brauner (Amutable) <[email protected]>
---
 .../selftests/filesystems/overlayfs/set_layers_via_fds.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/tools/testing/selftests/filesystems/overlayfs/set_layers_via_fds.c b/tools/testing/selftests/filesystems/overlayfs/set_layers_via_fds.c
index 3c0b93183348..7a293544233d 100644
--- a/tools/testing/selftests/filesystems/overlayfs/set_layers_via_fds.c
+++ b/tools/testing/selftests/filesystems/overlayfs/set_layers_via_fds.c
@@ -624,7 +624,7 @@ TEST_F(set_layers_via_fds, set_layers_via_detached_mount_fds)
 
 	ASSERT_EQ(sys_move_mount(fd_tmpfs, "", -EBADF, "/set_layers_via_fds_tmpfs", MOVE_MOUNT_F_EMPTY_PATH), 0);
 
-	fd_tmp = open_tree(fd_tmpfs, "u", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
+	fd_tmp = sys_open_tree(fd_tmpfs, "u", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
 	ASSERT_GE(fd_tmp, 0);
 
 	layer_fds[0] = openat(fd_tmp, "upper", O_CLOEXEC | O_DIRECTORY | O_PATH);
@@ -633,25 +633,25 @@ TEST_F(set_layers_via_fds, set_layers_via_detached_mount_fds)
 	layer_fds[1] = openat(fd_tmp, "work", O_CLOEXEC | O_DIRECTORY | O_PATH);
 	ASSERT_GE(layer_fds[1], 0);
 
-	layer_fds[2] = open_tree(fd_tmpfs, "l1", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
+	layer_fds[2] = sys_open_tree(fd_tmpfs, "l1", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
 	ASSERT_GE(layer_fds[2], 0);
 
-	layer_fds[3] = open_tree(fd_tmpfs, "l2", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
+	layer_fds[3] = sys_open_tree(fd_tmpfs, "l2", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
 	ASSERT_GE(layer_fds[3], 0);
 
-	layer_fds[4] = open_tree(fd_tmpfs, "l3", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
+	layer_fds[4] = sys_open_tree(fd_tmpfs, "l3", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
 	ASSERT_GE(layer_fds[4], 0);
 
-	layer_fds[5] = open_tree(fd_tmpfs, "l4", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
+	layer_fds[5] = sys_open_tree(fd_tmpfs, "l4", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
 	ASSERT_GE(layer_fds[5], 0);
 
-	layer_fds[6] = open_tree(fd_tmpfs, "d1", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
+	layer_fds[6] = sys_open_tree(fd_tmpfs, "d1", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
 	ASSERT_GE(layer_fds[6], 0);
 
-	layer_fds[7] = open_tree(fd_tmpfs, "d2", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
+	layer_fds[7] = sys_open_tree(fd_tmpfs, "d2", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
 	ASSERT_GE(layer_fds[7], 0);
 
-	layer_fds[8] = open_tree(fd_tmpfs, "d3", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
+	layer_fds[8] = sys_open_tree(fd_tmpfs, "d3", OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC);
 	ASSERT_GE(layer_fds[8], 0);
 
 	ASSERT_EQ(close(fd_tmpfs), 0);

-- 
2.47.3