svcrpc: sends on closed socket should stop immediately
svcrpc: sends on closed socket should stop immediately

svc_tcp_sendto sets XPT_CLOSE if we fail to transmit the entire reply.
However, the XPT_CLOSE won't be acted on immediately.  Meanwhile other
threads could send further replies before the socket is really shut
down.  This can manifest as data corruption: for example, if a truncated
read reply is followed by another rpc reply, that second reply will look
to the client like further read data.

Symptoms were data corruption preceded by svc_tcp_sendto logging
something like

	kernel: rpc-srv/tcp: nfsd: sent only 963696 when sending 1048708 bytes - shutting down socket

Cc: 4fbacc2fa0ffdbb11bf1ad6925b886ebd08dd15f@vger.kernel.org
Reported-by: Malahal Naineni <2818535284b90116b9d24c7042b346bf541c9efa@us.ibm.com>
Tested-by: Malahal Naineni <2818535284b90116b9d24c7042b346bf541c9efa@us.ibm.com>
Signed-off-by: J. Bruce Fields <51738506c1b2ccb0761f23bdc612c93babf738ea@redhat.com>

KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs