public synchronized FileSystemRef getFilesystemRefMountedAt(FSRL containerFSRL) {

		// Iterate the entire set of mounted filesystems searching for a match
		// (because there is no index of container-to-filesystems)
		for (Entry<FSRLRoot, FSCacheInfo> entry : filesystems.entrySet()) {
			FSRLRoot fsFSRL = entry.getKey();
			FSRL fsContainer = fsFSRL.getContainer();

			FileSystemRef ref = entry.getValue().ref;
			GFileSystem fs = ref.getFilesystem();
			if (fs == null || fsContainer == null) {
				continue;
			}

			if (containerFSRL.isEquivalent(fsContainer)) {
				return ref.dup();
			}
		}
		return null;
	}
Returns a new {@link FileSystemRef} to a already mounted {@link GFileSystem filesystem}
(keeping the filesystem pinned in memory without the risk of it being closed during
a race condition).
<p>
The caller is responsible for {@link FileSystemRef#close() closing} it when done.
<p>
Returns null if there is no filesystem mounted at the requested container fsrl.

@param containerFSRL {@link FSRL} location where a filesystem is already mounted
@return new {@link FileSystemRef} to the already mounted filesystem, or null
Ghidra/Features/Base/src/main/java/ghidra/formats/gfilesystem/FileSystemInstanceManager.java