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: J. 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
c45821d263 "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: Takashi Iwai <tiwai@suse.de>
Signed-off-by: J. 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: J. Bruce Fields <bfields@redhat.com>
* 'for-2.6.38' of git://linux-nfs.org/~bfields/linux: (62 commits)
nfsd4: fix callback restarting
nfsd: break lease on unlink, link, and rename
nfsd4: break lease on nfsd setattr
nfsd: don't support msnfs export option
nfsd4: initialize cb_per_client
nfsd4: allow restarting callbacks
nfsd4: simplify nfsd4_cb_prepare
nfsd4: give out delegations more quickly in 4.1 case
nfsd4: add helper function to run callbacks
nfsd4: make sure sequence flags are set after destroy_session
nfsd4: re-probe callback on connection loss
nfsd4: set sequence flag when backchannel is down
nfsd4: keep finer-grained callback status
rpc: allow xprt_class->setup to return a preexisting xprt
rpc: keep backchannel xprt as long as server connection
rpc: move sk_bc_xprt to svc_xprt
nfsd4: allow backchannel recovery
nfsd4: support BIND_CONN_TO_SESSION
nfsd4: modify session list under cl_lock
Documentation: fl_mylease no longer exists
...
Fix up conflicts in fs/nfsd/vfs.c with the vfs-scale work. The
vfs-scale work touched some msnfs cases, and this merge removes support
for that entirely, so the conflict was trivial to resolve.
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: J. 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: J. 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: J. 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: J. 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: J. Bruce Fields <bfields@redhat.com>
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: Takuma Umeya <tumeya@redhat.com>
[bfields@redhat.com: Simplify gen_callback arguments, use helper function]
Signed-off-by: J. 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: J. 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: J. 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: J. 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: Casey Bodley <cbodley@citi.umich.edu>
Reviewed-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. 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: Tejun Heo <tj@kernel.org>
Acked-by: "David S. Miller" <davem@davemloft.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Evgeniy 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: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When server gets drc mem fail, it should reply error to client.
Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: J. 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: Dan Carpenter <error27@gmail.com>
Signed-off-by: J. 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: Arnd Bergmann <arnd@arndb.de>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Linus 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: J. 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: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus 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: J. Bruce Fields <bfields@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus 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: Arnd Bergmann <arnd@arndb.de>
Acked-by: J. Bruce Fields <bfields@redhat.com>
* 'for-2.6.37' of git://linux-nfs.org/~bfields/linux: (99 commits)
svcrpc: svc_tcp_sendto XPT_DEAD check is redundant
svcrpc: no need for XPT_DEAD check in svc_xprt_enqueue
svcrpc: assume svc_delete_xprt() called only once
svcrpc: never clear XPT_BUSY on dead xprt
nfsd4: fix connection allocation in sequence()
nfsd4: only require krb5 principal for NFSv4.0 callbacks
nfsd4: move minorversion to client
nfsd4: delay session removal till free_client
nfsd4: separate callback change and callback probe
nfsd4: callback program number is per-session
nfsd4: track backchannel connections
nfsd4: confirm only on succesful create_session
nfsd4: make backchannel sequence number per-session
nfsd4: use client pointer to backchannel session
nfsd4: move callback setup into session init code
nfsd4: don't cache seq_misordered replies
SUNRPC: Properly initialize sock_xprt.srcaddr in all cases
SUNRPC: Use conventional switch statement when reclassifying sockets
sunrpc/xprtrdma: clean up workqueue usage
sunrpc: Turn list_for_each-s into the ..._entry-s
...
Fix up trivial conflicts (two different deprecation notices added in
separate branches) in Documentation/feature-removal-schedule.txt
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: J. Bruce Fields <bfields@redhat.com>
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: J. 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: J. Bruce Fields <bfields@redhat.com>
Only one of the nfsd4_callback_probe callers actually cares about
changing the callback information.
Signed-off-by: J. 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: J. 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: J. 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: J. 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: J. 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: J. 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: J. Bruce Fields <bfields@citi.umich.edu>
This prepares the removal of the big kernel lock from the
file locking code. We still use the BKL as long as fs/lockd
uses it and ceph might sleep, but we can flip the definition
to a private spinlock as soon as that's done.
All users outside of fs/lockd get converted to use
lock_flocks() instead of lock_kernel() where appropriate.
Based on an earlier patch to use a spinlock from Matthew
Wilcox, who has attempted this a few times before, the
earliest patch from over 10 years ago turned it into
a semaphore, which ended up being slower than the BKL
and was subsequently reverted.
Someone should do some serious performance testing when
this becomes a spinlock, since this has caused problems
before. Using a spinlock should be at least as good
as the BKL in theory, but who knows...
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Sage Weil <sage@newdream.net>
Cc: linux-kernel@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Commit 78155ed75f "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: Bian Naimeng <biannm@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>