vfs: new internal helper: mnt_has_parent(mnt)
vfsmounts have ->mnt_parent pointing either to a different vfsmount
or to itself; it's never NULL and termination condition in loops
traversing the tree towards root is mnt == mnt->mnt_parent. At least
one place (see the next patch) is confused about what's going on;
let's add an explicit helper checking it right way and use it in
all places where we need it. Not that there had been too many,
but...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/mount.h b/fs/mount.h
new file mode 100644
index 0000000..7890e49
--- /dev/null
+++ b/fs/mount.h
@@ -0,0 +1,6 @@
+#include <linux/mount.h>
+
+static inline int mnt_has_parent(struct vfsmount *mnt)
+{
+ return mnt != mnt->mnt_parent;
+}