code: public void releaseAccess(long sessionId, long blockId) {
      try (LockResource lr = new LockResource(mLock)) {
        Key key = new Key(sessionId, blockId);
        if (!mBlocks.containsKey(key)) {
          LOG.warn("Key (block ID: {}, session ID {}) is not found when releasing the UFS block.",
              blockId, sessionId);
        }
        mBlocks.remove(key);
        Set<Long> blockIds = mSessionIdToBlockIds.get(sessionId);
        if (blockIds != null) {
          blockIds.remove(blockId);
          if (blockIds.isEmpty()) {
            mSessionIdToBlockIds.remove(sessionId);
          }
        }
        Set<Long> sessionIds = mBlockIdToSessionIds.get(blockId);
        if (sessionIds != null) {
          sessionIds.remove(sessionId);
          if (sessionIds.isEmpty()) {
            mBlockIdToSessionIds.remove(blockId);
          }
        }
      }
    }
docs: Releases the access token of this block by removing this (sessionId, blockId) pair from the
  store.
  
  @param sessionId the session ID
  @param blockId the block ID