I have a very specific use for an NFS mount over a WAN, and allowing for 
much larger expected READDIRPLUS requests actually improves performance 
by at least a factor of 10 by eliminating the round-trip latency that 
results from the application's single-threaded 
readdir/stat/stat/stat/... behavior.  Rather than maintain a hacked 
kernel on my end, I'd rather the READDIRPLUS limit be a mount option.  
Hence, the following patch.  It defaults to the old behavior 
(8*PAGE_SIZE), but with a properly-prepared mount binary will allow the 
client to specify a limit.

I'm not subscribed to the list, so please CC me in any relevant discussion.

Kyle