Add a helper to directly set the TCP_KEEP_IDLE sockopt from kernel space without going through a fake uaccess. Change-Id: Ie673ab61bb47f73dcd200c3a3ffd14ecae5eebc4 Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>