Allow the number of available slots to grow with the TCP window size.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This throttles the allocation of new slots when the socket is busy
reconnecting and/or is out of buffer space.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Change explicit references to CONFIG_NFS_V4_1 to implicit ones
Get rid of the unnecessary defines in backchannel_rqst.c and
bc_svc.c: the Makefile takes care of those dependency.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If the NLM daemon is killed on the NFS server, we can currently end up
hanging forever on an 'unlock' request, instead of aborting. Basically,
if the rpcbind request fails, or the server keeps returning garbage, we
really want to quit instead of retrying.
Tested-by: NVasily Averin <vvs@sw.ru>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

Commit b0b0c0a2 "nfsd: add proc file listing kernel's gss_krb5
enctypes" added an nunnecessary dependency of nfsd on the auth_rpcgss
module.

It's a little ad hoc, but since the only piece of information nfsd needs
from rpcsec_gss_krb5 is a single static string, one solution is just to
share it with an include file.

Cc: stable@kernel.org
Reported-by: NMichael Guntsche <mike@it-loops.com>
Cc: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Initialize xdr_stream and xdr_buf using an array of page pointers
and length of buffer.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>

TI-RPC introduces the capability of performing RPC over AF_LOCAL
sockets.  It uses this mainly for registering and unregistering
local RPC services securely with the local rpcbind, but we could
also conceivably use it as a generic upcall mechanism.

This patch provides a client-side only implementation for the moment.
We might also consider a server-side implementation to provide
AF_LOCAL access to NLM (for statd downcalls, and such like).

Autobinding is not supported on kernel AF_LOCAL transports at this
time.  Kernel ULPs must specify the pathname of the remote endpoint
when an AF_LOCAL transport is created.  rpcbind supports registering
services available via AF_LOCAL, so the kernel could handle it with
some adjustment to ->rpcbind and ->set_port.  But we don't need this
feature for doing upcalls via well-known named sockets.

This has not been tested with ULPs that move a substantial amount of
data.  Thus, I can't attest to how robust the write_space and
congestion management logic is.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

On occasion, it is useful for the NFS layer to distinguish between
soft timeouts and other EIO errors due to (say) encoding errors,
or authentication errors.

The following patch ensures that the default behaviour of the RPC
layer remains to return EIO on soft timeouts (until we have
audited all the callers).
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If we fail to contact the gss upcall program, then no message will
be sent to the server.  The client still updated the sequence number,
however, and this lead to NFS4ERR_SEQ_MISMATCH for the next several
RPC calls.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Ensure that we immediately read and buffer data from the incoming TCP
stream so that we grow the receive window quickly, and don't deadlock on
large READ or WRITE requests.

Also do some minor exit cleanup.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

When sec=<something> is not presented as a mount option,
we should attempt to determine what security flavor the
server is using.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Use our own async error handler.
Mark the layout as failed and retry i/o through the MDS on specified errors.

Update the mds_offset in nfs_readpage_retry so that a failed short-read retry
to a DS gets correctly resent through the MDS.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Although they run as rpciod background tasks, under normal operation
(i.e. no SIGKILL), functions like nfs_sillyrename(), nfs4_proc_unlck()
and nfs4_do_close() want to be fully synchronous. This means that when we
exit, we want all references to the rpc_task to be gone, and we want
any dentry references etc. held by that task to be released.

For this reason these functions call __rpc_wait_for_completion_task(),
followed by rpc_put_task() in the expectation that the latter will be
releasing the last reference to the rpc_task, and thus ensuring that the
callback_ops->rpc_release() has been called synchronously.

This patch fixes a race which exists due to the fact that
rpciod calls rpc_complete_task() (in order to wake up the callers of
__rpc_wait_for_completion_task()) and then subsequently calls
rpc_put_task() without ensuring that these two steps are done atomically.

In order to avoid adding new spin locks, the patch uses the existing
waitqueue spin lock to order the rpc_task reference count releases between
the waiting process and rpciod.
The common case where nobody is waiting for completion is optimised for by
checking if the RPC_TASK_ASYNC flag is cleared and/or if the rpc_task
reference count is 1: in those cases we drop trying to grab the spin lock,
and immediately free up the rpc_task.

Those few processes that need to put the rpc_task from inside an
asynchronous context and that do not care about ordering are given a new
helper: rpc_put_task_async().
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The information required to find the nfs_client cooresponding to the incoming
back channel request is contained in the NFS layer. Perform minimal checking
in the RPC layer pg_authenticate method, and push more detailed checking into
the NFS layer where the nfs_client can be found.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This allows us to reuse the xprt associated with a server connection if
one has already been set up.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

This seems obviously transport-level information even if it's currently
used only by the server socket code.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

vm_map_ram() is not available on NOMMU platforms, and causes trouble
on incoherrent architectures such as ARM when we access the page data
through both the direct and the virtual mapping.

The alternative is to use the direct mapping to access page data
for the case when we are not crossing a page boundary, but to copy
the data into a linear scratch buffer when we are accessing data
that spans page boundaries.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: NMarc Kleine-Budde <mkl@pengutronix.de>
Cc: stable@kernel.org  [2.6.37]

Remove kobject.h from files which don't need it, notably,
sched.h and fs.h.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Differentiate from server backchannel
Signed-off-by: NAndy Adamson <andros@netapp.com>
Acked-by: NBruce Fields <bfields@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Fixes a bug where the nfs_client could be freed during callback processing.
Refactor nfs_find_client to use minorversion specific means to locate the
correct nfs_client structure.

In the NFS layer, V4.0 clients are found using the callback_ident field in the
CB_COMPOUND header.  V4.1 clients are found using the sessionID in the
CB_SEQUENCE operation which is also compared against the sessionID associated
with the back channel thread after a successful CREATE_SESSION.

Each of these methods finds the one an only nfs_client associated
with the incoming callback request - so nfs_find_client_next is not needed.

In the RPC layer, the pg_authenticate call needs to find the nfs_client. For
the v4.0 callback service, the callback identifier has not been decoded so a
search by address, version, and minorversion is used.  The sessionid for the
sessions based callback service has (usually) not been set for the
pg_authenticate on a CB_NULL call which can be sent prior to the return
of a CREATE_SESSION call, so the sessionid associated with the back channel
thread is not used to find the client in pg_authenticate for CB_NULL calls.

Pass the referenced nfs_client to each CB_COMPOUND operation being proceesed
via the new cb_process_state structure. The reference is held across
cb_compound processing.

Use the new cb_process_state struct to move the NFS4ERR_RETRY_UNCACHED_REP
processing from process_op into nfs4_callback_sequence where it belongs.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The sessions based callback service is started prior to the CREATE_SESSION call
so that it can handle CB_NULL requests which can be sent before the
CREATE_SESSION call returns and the session ID is known.

Set the callback sessionid after a sucessful CREATE_SESSION.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Move the current sock create and destroy routines into the new transport ops.
Back channel socket will be destroyed by the svc_closs_all call in svc_destroy.

Added check: only TCP supported on shared back channel.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Acked-by: NBruce Fields <bfields@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Currently we use -EAGAIN returns to determine when to drop a deferred
request.  On its own, that is error-prone, as it makes us treat -EAGAIN
returns from other functions specially to prevent inadvertent dropping.

So, use a flag on the request instead.

Returning an error on request deferral is still required, to prevent
further processing, but we no longer need worry that an error return on
its own could result in a drop.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NNeilBrown <neilb@suse.de>
[bfields@redhat.com: moved svcauth_unix_purge outside ifdef's.]
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The xpt_pool field is only used for reporting BUGs.
And it isn't used correctly.

In particular, when it is cleared in svc_xprt_received before
XPT_BUSY is cleared, there is no guarantee that either the
compiler or the CPU might not re-order to two assignments, just
setting xpt_pool to NULL after XPT_BUSY is cleared.

If a different cpu were running svc_xprt_enqueue at this moment,
it might see XPT_BUSY clear and then xpt_pool non-NULL, and
so BUG.

This could be fixed by calling
  smp_mb__before_clear_bit()
before the clear_bit.  However as xpt_pool isn't really used,
it seems safest to simply remove xpt_pool.

Another alternate would be to change the clear_bit to
clear_bit_unlock, and the test_and_set_bit to test_and_set_bit_lock.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Now that all client-side XDR decoder routines use xdr_streams, there
should be no need to support the legacy calling sequence [rpc_rqst *,
__be32 *, RPC res *] anywhere.  We can construct an xdr_stream in the
generic RPC code, instead of in each decoder function.

This is a refactoring change.  It should not cause different behavior.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Tested-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Now that all client-side XDR encoder routines use xdr_streams, there
should be no need to support the legacy calling sequence [rpc_rqst *,
__be32 *, RPC arg *] anywhere.  We can construct an xdr_stream in the
generic RPC code, instead of in each encoder function.

Also, all the client-side encoder functions return 0 now, making a
return value superfluous.  Take this opportunity to convert them to
return void instead.

This is a refactoring change.  It should not cause different behavior.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Tested-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If a connection is closed just after a sequence or create_session
is sent over it, we could end up trying to register a callback that will
never get called since the xprt is already marked dead.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

A helper for decoding a fixed length opaque value.
Returns a pointer to the next item in the xdr stream.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We sometimes need to be able to read ahead in an xdr_stream without
incrementing the current pointer position.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

NFSv4.1 needs warning when a client tcp connection goes down, if that
connection is being used as a backchannel, so that it can warn the
client that it has lost the backchannel connection.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Unfortunately, spkm3 never got very far; while interoperability with one
other implementation was demonstrated at some point, problems were found
with the spec that were deemed not worth fixing.

The kernel code is useless on its own without nfs-utils patches which
were never merged into nfs-utils, and were only ever available from
citi.umich.edu.  They appear not to have been updated since 2005.

Therefore it seems safe to assume that this code has no users, and never
will.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The net is known from the xprt_create and this tagging will also
give un the context in the conntection workers where real sockets
are created.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

After this the socket creation in it knows the context.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>