Teach the NFS server to reject invalid create_session flags.

Also do some minor formatting adjustments.
Signed-off-by: NMi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

According to rfc5661,

  ca_maxresponsesize_cached:

     Like ca_maxresponsesize, but the maximum size of a reply that
     will be stored in the reply cache (Section 2.10.6.1).  For each
     channel, the server MAY decrease this value, but MUST NOT
     increase it.

the latest kernel(2.6.38-rc8) may increase the value for ignoring
request's ca_maxresponsesize_cached value. We should not ignore it.
Signed-off-by: NMi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Make sure we properly reference count the struct files that a lock
depends on, and release them when the lock stateid is released.

This fixes a major leak of struct files when using locking over nfsv4.

Cc: stable@kernel.org
Reported-by: NRick Koshi <nfs-bug-report@more-right-rudder.com>
Tested-by: NIvo Přikryl <prikryl@eurosat.cz>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Minor cleanup in preparation for a bugfix--moving some code to avoid
forward references, etc.  No change in functionality.

Cc: stable@kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

These macros had never been used for several years.
So, remove them.
Signed-off-by: NShan Wei <shanwei@cn.fujitsu.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

In case of a nonempty list, the return on error here is obviously bogus;
it ends up being a pointer to the list head instead of to any valid
delegation on the list.

In particular, if nfsd4_delegreturn() hits this case, and you're quite unlucky,
then renew_client may oops, and it may take an embarassingly long time to
figure out why.  Facepalm.

BUG: unable to handle kernel NULL pointer dereference at 0000000000000090
IP: [<ffffffff81292965>] nfsd4_delegreturn+0x125/0x200
...

Cc: stable@kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Instead of acquiring one lease each time another client opens a file,
nfsd can acquire just one lease to represent all of them, and reference
count it to determine when to release it.

This fixes a regression introduced by
c45821d2 "locks: eliminate fl_mylease
callback": after that patch, only the struct file * is used to determine
who owns a given lease.  But since we recently converted the server to
share a single struct file per open, if we acquire multiple leases on
the same file from nfsd, it then becomes impossible on unlocking a lease
to determine which of those leases (all of whom share the same struct
file *) we meant to remove.

Thanks to Takashi Iwai <tiwai@suse.de> for catching a bug in a previous
version of this patch.
Tested-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Modify fi_delegations only under the recall_lock, allowing us to use
that list on lease breaks.

Also some trivial cleanup to simplify later changes.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

These aren't all that useful, and get in the way of the next steps.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Splitting some code into a separate function which we'll be adding some
more to.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Also share some common exit code.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

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

We'll be adding some more code here soon.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

If we lose the backchannel and then the client repairs the problem,
resend any callbacks.

We use a new cb_done flag to track whether there is still work to be
done for the callback or whether it can be destroyed with the rpc.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

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

If this loses any backchannel, make sure we have a chance to notice that
and set the sequence flags.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

This makes sure we set the sequence flag when necessary.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Implement the SEQ4_STATUS_CB_PATH_DOWN flag.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Distinguish between when the callback channel is known to be down, and
when it is not yet confirmed.  This will be useful in the 4.1 case.

Also, we don't seem to be using the fact that this field is atomic.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Now that we have a list of connections to choose from, we can teach the
callback code to just pick a suitable connection and use that, instead
of insisting on forever using the connection that the first
create_session was sent with.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Basic xdr and processing for BIND_CONN_TO_SESSION.  This adds a
connection to the list of connections associated with a session.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

We want to traverse this from the callback code.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

when callback is generated in NFSv4 server, it doesn't set the source
address. When an alias IP is utilized on NFSv4 server and suppose the
client is accessing via that alias IP (e.g. eth0:0), the client invokes
the callback to the IP address that is set on the original device (e.g.
eth0). This behavior results in timeout of xprt.
The patch sets the IP address that the client should invoke callback to.
Signed-off-by: NTakuma Umeya <tumeya@redhat.com>
[bfields@redhat.com: Simplify gen_callback arguments, use helper function]
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The nfs server only supports read delegations for now, so we don't care
how conflicts are determined.  All we care is that unlocks are
recognized as matching the leases they are meant to remove.  After the
last patch, a comparison of struct files will work for that purpose.  So
we no longer need this callback.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

When we converted to sharing struct filess between nfs4 opens I went too
far and also used the same mechanism for delegations.  But keeping
a reference to the struct file ensures it will outlast the lease, and
allows us to remove the lease with the same file as we added it.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

nfsd controls the lifetime of the lease, not the lock code, so there's
no need for this callback on lease destruction.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

We no longer need a few of these special cases.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Instead of failing to find client entries which don't match the
minorversion, we should be finding them, then either erroring out or
expiring them as appropriate.

This also fixes a problem which would cause the 4.1 server to fail to
recognize clients after a second reboot.
Reported-by: NCasey Bodley <cbodley@citi.umich.edu>
Reviewed-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Reviewed-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

cancel_rearming_delayed_work[queue]() has been superceded by
cancel_delayed_work_sync() quite some time ago.  Convert all the
in-kernel users.  The conversions are completely equivalent and
trivial.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: N"David S. Miller" <davem@davemloft.net>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Acked-by: NEvgeniy Polyakov <zbr@ioremap.net>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: netdev@vger.kernel.org
Cc: Anton Vorontsov <cbou@mail.ru>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Alex Elder <aelder@sgi.com>
Cc: xfs-masters@oss.sgi.com
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: netfilter-devel@vger.kernel.org
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: linux-nfs@vger.kernel.org

At the latest kernel(2.6.37-rc1), server just initialize the forechannel
at init_forechannel_attrs, but don't reflect it to reply.

After initialize the session success, we should copy the forechannel info
to nfsd4_create_session struct.
Reviewed-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NMi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

When server gets drc mem fail, it should reply error to client.
Signed-off-by: NMi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

We're refusing to support a mandatory features of 4.1, so serverfault
seems the better error; see e.g.:

	http://www.ietf.org/mail-archive/web/nfsv4/current/msg07638.htmlSigned-off-by: NJ. Bruce Fields <bfields@redhat.com>

The original code would oops if this were called from nfsd4_setattr()
because "filpp" is NULL.

(Note this case is currently impossible, as long as we only give out
read delegations.)
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Lock_kernel is gone from the code, so the comments should be updated,
too.  nfsd now uses lock_flocks instead of lock_kernel to protect
against posix file locks.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NJ. Bruce Fields <bfields@redhat.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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>

The caller allocated it, the caller should free it.

The only issue so far is that we could change the flp pointer even on an
error return if the fl_change callback failed.  But we can simply move
the flp assignment after the fl_change invocation, as the callers don't
care about the flp return value if the setlease call failed.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The NFSv4 server was initializing the dp->dl_flock pointer by the
somewhat ridiculous method of a locks_copy_lock callback.

Now that setlease uses the passed-in lock instead of doing a copy,
dl_flock no longer gets set, resulting in the lock leaking on delegation
release, and later possible hangs (among other problems).

So, initialize dl_flock and get rid of the callback.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

As suggested by Christoph Hellwig, this moves allocation
of new file locks out of generic_setlease into the
callers, nfs4_open_delegation and fcntl_setlease in order
to allow GFP_KERNEL allocations when lock_flocks has
become a spinlock.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NJ. Bruce Fields <bfields@redhat.com>

We're doing an allocation under a spinlock, and ignoring the
possibility of allocation failure.

A better fix wouldn't require an unnecessary allocation in the common
case, but we'll leave that for later.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>