The minorversion seems more a property of the client than the callback
channel.

Some time we should probably also enforce consistent minorversion usage
from the client; for now, this is just a cosmetic change.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Have unhash_client_locked() remove client and associated sessions from
global hashes, but delay further dismantling till free_client().

(After unhash_client_locked(), the only remaining references outside the
destroying thread are from any connections which have xpt_user callbacks
registered.)

This will simplify locking on session destruction.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Only one of the nfsd4_callback_probe callers actually cares about
changing the callback information.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The callback program is allowed to depend on the session which the
callback is going over.

No change in behavior yet, while we still only do callbacks over a
single session for the lifetime of the client.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

We need to keep track of which connections are available for use with
the backchannel, which for the forechannel, and which for both.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Following rfc 5661, section 18.36.4: "If the session is not successfully
created, then no changes are made to any client records on the server."
We shouldn't be confirming or incrementing the sequence id in this case.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Currently we don't deal well with a client that has multiple sessions
associated with it (even simultaneously, or serially over the lifetime
of the client).

In particular, we don't attempt to keep the backchannel running after
the original session diseappears.

We will fix that soon.

Once we do that, we need the slot sequence number to be per-session;
otherwise, for example, we cannot correctly handle a case like this:

	- All session 1 connections are lost.
	- The client creates session 2.  We use it for the backchannel
	  (since it's the only working choice).
	- The client gives us a new connection to use with session 1.
	- The client destroys session 2.

At this point our only choice is to go back to using session 1.  When we
do so we must use the sequence number that is next for session 1.  We
therefore need to maintain multiple sequence number streams.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Instead of copying the sessionid, use the new cl_cb_session pointer,
which indicates which session we're using for the backchannel.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

The backchannel should  be associated with a session, it isn't really
global to the client.

We do, however, want a pointer global to the client which tracks which
session we're currently using for client-based callbacks.

This is a first step in that direction; for now, just reshuffling of
code with no significant change in behavior.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Expire clients more promptly, at the expense of possibly running the
laundromat thread more frequently.

Though it's not the default, I'd like it to be feasible to run with a
lease time of just a few seconds, at which point a minimum 10 second
wait between laundromat runs seems a little much.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Commit 78155ed7 "nfsd4: distinguish
expired from stale stateids" attempted to distinguish expired and stale
stateid's using time information that may not have been completely
reliable, so I reverted it.

That was throwing out the baby with the bathwater; we still do want to
return expired, but let's do that using the simpler approach of just
assuming any stateid is expired if it looks like it was given out by the
current server instance, but we can't find it any more.

This may help clients that are recovering from network partitions.
Reported-by: NBian Naimeng <biannm@cn.fujitsu.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

As long as we're not implementing any session security, we should just
automatically add any new connections that come along to the list of
sessions associated with the session.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Remove connections from the list when they go down.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

The spec requires us in various places to keep track of the connections
associated with each session.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Changes:
	- make sure session memory reservation is released on failure
	  path.
	- use min_t()/min() for more compact code in several places.
	- break alloc_init_session into smaller pieces.
	- miscellaneous other cleanup.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

This returns an nfs error, not -ERRNO.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Note we're allocating an array of nfsd4_slot *'s, not nfsd4_slot's.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Instead of creating the new rpc client from a regular server thread,
set a flag, kick off a null call, and allow the null call to do the work
of setting up the client on the callback workqueue.

Use a spinlock to ensure the callback work gets a consistent view of the
callback parameters.

This allows, for example, changing the callback from contexts where
sleeping is not allowed.  I hope it will also keep the locking simple as
we add more session and trunking features, by serializing most of the
callback-specific work.

This also closes a small race where the the new cb_ident could be used
with an old connection (or vice-versa).
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

I don't see the point of the separate struct.  It seems to just be
getting in the way.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

This will eventually allow us, for example, to kick off null callback
from contexts where we can't sleep.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Make the recall callback code more generic, so that other callbacks
will be able to use it too.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

With apologies for the gratuitous rename, the new name seems more
helpful to me.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

These two structs don't really need to be distinct as far as I can tell.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Now that we have both nfsd4_callback and nfsd4_cb_conn structures, I get
confused if variables of both types are always named cb....
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

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>

The existing code adjusted it based on the worst case scenario for the returned
bitmap and the best case scenario for the supported attrs attribute.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[bfields@redhat.com: removed likely/unlikely's]
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

There are two calls that operate on ip_map_cache and are
directly called from the nfsd code. Other places will be
handled in a different way.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Note with "first" always 0, and "lastflags" initially 0, we always dump
a spurious set of 0 flags at the start, among other problems.

Fix.  And attempt to make the code a little more obvious.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The git://linux-nfs.org/~bfields/linux.git nfsd-next branch doesn't
compile when nfsd is a module with the following error:

   ERROR: "get_task_comm" [fs/nfsd/nfsd.ko] undefined!

Replace the get_task_comm call with direct comm access, which is
safe for current.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Add CONFIG_NFSD_DEPRECATED, default to y.
Only include deprecated interface if this is defined.
This allows distros to remove this interface before the official
removal, and allows developers to test without it.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The syscall interface is has been replaced by a more flexible
interface since 2.6.0.  It is time to work towards discarding
the old interface.

So add a entry in feature-removal-schedule.txt and print a warning
when the interface is used.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

This patch removes all but one call to lock_kernel() from the server.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The idmap code manages request deferal by waiting for a reply from
userspace rather than putting the NFS request on a queue to be retried
from the start.
Now that the common deferal code does this there is no need for the
special code in idmap.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Now that a slight delay in getting a reply to an upcall doesn't
require deferring of requests, request deferral for all NFSv4
requests - the concept doesn't really fit with the v4 model.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The NFSv4 client's callback server calls svc_gss_principal(), which
is defined in the auth_rpcgss.ko

The NFSv4 server has the same dependency, and in addition calls
svcauth_gss_flavor(), gss_mech_get_by_pseudoflavor(),
gss_pseudoflavor_to_service() and gss_mech_put() from the same module.

The module auth_rpcgss itself has no dependencies aside from sunrpc,
so we only need to select RPCSEC_GSS.
Reported-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Hi,

An NFS client executes a statfs("file", &buff) call.
"file" exists / existed, the client has read / written it,
but it has already closed it.

user_path(pathname, &path) looks up "file" successfully in the
directory-cache  and restarts the aging timer of the directory-entry.
Even if "file" has already been removed from the server, because the
lookupcache=positive option I use, keeps the entries valid for a while.

nfs_statfs() returns ESTALE if "file" has already been removed from the
server.

If the user application repeats the statfs("file", &buff) call, we
are stuck: "file" remains young forever in the directory-cache.
Signed-off-by: NZoltan Menyhart  <Zoltan.Menyhart@bull.net>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

Reported-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org