pub fn find_mount_target_by_source(dev: &str) -> Result<Option<Utf8PathBuf>>Expand description
Find the mount target of a given source device in the current mount
namespace. Returns Ok(None) if the device is not mounted.
Used by callers that want to gracefully handle the case where a
device they intended to mount is already mounted somewhere else
(which would cause a fresh mount(2) to return EBUSY). Note this
intentionally queries the caller’s own mount namespace, not pid 1’s
(unlike is_mounted_in_pid1_mountns, which exists to answer a
different question: whether the host already has something
mounted before bootc unshares its own namespace). Callers of this
function are expected to have already unshared their own mount
namespace and are looking up a mount they intend to operate on
directly (e.g. remount) in that same namespace.