9baaa7deae
Register iterate_shared if it exists so the kernel will used shared lock and allowing concurrent readdir. Also, use shared lock when doing llseek with SEEK_DATA or SEEK_HOLE to allow concurrent seeking. Signed-off-by: Chunwei Chen <david.chen@osnexus.com> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #4664 Closes #4665