This patch fixes the bug that was reported in
  http://bugzilla.kernel.org/show_bug.cgi?id=14053

If we're in the case where we need to force a reencode and then resend of
the RPC request, due to xprt_transmit failing with a networking error, then
we _must_ retransmit the entire request.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
  It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT

  This will make hardirq.h inclusion cheaper for every PREEMPT=n config
  (which includes allmodconfig/allyesconfig, BTW)

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The sunrpc module uses rcu_call() thus it should use rcu_barrier() on
module unload.

Have not verified that the possibility for new call_rcu() callbacks
has been disabled.  As a hint for checking, the functions calling
call_rcu() (unx_destroy_cred and generic_destroy_cred) are
registered as crdestroy function pointer in struct rpc_credops.

Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Jesper Dangaard Brouer <hawk@comx.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>

* 'for-2.6.31' of git://fieldses.org/git/linux-nfsd: (60 commits)
  SUNRPC: Fix the TCP server's send buffer accounting
  nfsd41: Backchannel: minorversion support for the back channel
  nfsd41: Backchannel: cleanup nfs4.0 callback encode routines
  nfsd41: Remove ip address collision detection case
  nfsd: optimise the starting of zero threads when none are running.
  nfsd: don't take nfsd_mutex twice when setting number of threads.
  nfsd41: sanity check client drc maxreqs
  nfsd41: move channel attributes from nfsd4_session to a nfsd4_channel_attr struct
  NFS: kill off complicated macro 'PROC'
  sunrpc: potential memory leak in function rdma_read_xdr
  nfsd: minor nfsd_vfs_write cleanup
  nfsd: Pull write-gathering code out of nfsd_vfs_write
  nfsd: track last inode only in use_wgather case
  sunrpc: align cache_clean work's timer
  nfsd: Use write gathering only with NFSv2
  NFSv4: kill off complicated macro 'PROC'
  NFSv4: do exact check about attribute specified
  knfsd: remove unreported filehandle stats counters
  knfsd: fix reply cache memory corruption
  knfsd: reply cache cleanups
  ...

xprt_alloc_bc_request() is always called in soft interrupt context.
Grab the spin_lock instead of the bottom half spin_lock.  Softirqs
do not preempt other softirqs running on the same processor, so there
is no need to disable bottom halves.

Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Currently, the sunrpc server is refusing to allow us to process new RPC
calls if the TCP send buffer is 2/3 full, even if we do actually have
enough free space to guarantee that we can send another request.
The following patch fixes svc_tcp_has_wspace() so that we only stop
processing requests if we know that the socket buffer cannot possibly fit
another reply.

It also fixes the tcp write_space() callback so that we only clear the
SOCK_NOSPACE flag when the TCP send buffer is less than 2/3 full.
This should ensure that the send window will grow as per the standard TCP
socket code.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Conflicts:
	fs/nfs/client.c
	fs/nfs/super.c

The 'rq_received' member of 'struct rpc_rqst' is used to track when we
have received a reply to our request.  With v4.1, the backchannel
can now accept callback requests over the existing connection.  Rename
this field to make it clear that it is only used for tracking reply bytes
and not all bytes received on the connection.

Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>

Obtain the rpc_xprt from the rpc_rqst so that calls and callback replies
can both use the same code path.  A client needs the rpc_xprt in order
to reply to a callback.

Signed-off-by: Rahul Iyer <iyer@netapp.com>
Signed-off-by: Ricardo Labiaga <ricardo.labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>