The NFSv4 server's fl_break callback can sleep (dropping the BKL), in
order to allocate a new rpc task to send a recall to the client.
As far as I can tell this doesn't cause any races in the current code,
but the analysis is difficult. Also, the sleep here may complicate the
move away from the BKL.
So, just schedule some work to do the job for us instead. The work will
later also prove useful for restarting a call after the callback
information is changed.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Any null probe rpc will be synchronously destroyed by the
rpc_shutdown_client() in expire_client(), so the rpc task cannot outlast
the nfs4 client. Therefore there's no need for that task to hold a
reference on the client.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Instead of allocating this small structure, just include it in the
delegation.
The nfsd4_callback structure isn't really necessary yet, but we plan to
add to it all the information necessary to perform a callback.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Instead of accessing the lease time directly, some users call
nfs4_lease_time(), and some a macro, NFSD_LEASE_TIME, defined as
nfs4_lease_time(). Neither layer of indirection serves any purpose.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The server's callback client should stop trying to connect to the
client's callback server as soon as it gets ECONNREFUSED.
The NFS server's callback client does not call rpc_ping(), but appears
to have it's own "ping" procedure, so it wasn't covered by commit
caabea8a.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The new .h files have paths at the top that are now out of date. While
we're here, just remove all of those from fs/nfsd; they never served any
purpose.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Lots of include/linux/nfsd/* headers are only used by
nfsd module. Move them to the source directory
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Now that the headers are fixed and carry their own wait, all fs/nfsd/
source files can include a minimal set of headers. and still compile just
fine.
This patch should improve the compilation speed of the nfsd module.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This patch enables the use of the nfsv4.1 backchannel.
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
[initialize rpc_create_args.bc_xprt too]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Implement the cb_sequence callback conforming to draft-ietf-nfsv4-minorversion1
Note: highest slot id and target highest slot id do not have to be 0
as was previously implemented. They can be greater than what the
nfs server sent if the client supports a larger slot table on the
backchannel. At this point we just ignore that.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
[Rework the back channel xdr using the shared v4.0 and v4.1 framework.]
Signed-off-by: Andy Adamson <andros@netapp.com>
[fixed indentation]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfsd41: use nfsd4_cb_sequence for callback minorversion]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfsd41: fix verification of CB_SEQUENCE highest slot id[
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfsd41: Backchannel: Remove old backchannel serialization]
[nfsd41: Backchannel: First callback sequence ID should be 1]
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfsd41: decode_cb_sequence does not need to actually decode ignored fields]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Follows the model used by the NFS client. Setup the RPC prepare and done
function pointers so that we can populate the sequence information if
minorversion == 1. rpc_run_task() is then invoked directly just like
existing NFS client operations do.
nfsd4_cb_prepare() determines if the sequence information needs to be setup.
If the slot is in use, it adds itself to the wait queue.
nfsd4_cb_done() wakes anyone sleeping on the callback channel wait queue
after our RPC reply has been received. It also sets the task message
result pointer to NULL to clearly indicate we're done using it.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
[define and initialize cl_cb_seq_nr here]
[pulled out unused defintion of nfsd4_cb_done]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Follow the model we use in the client. Make the sequence arguments
part of the regular RPC arguments. None of the callbacks that are
soon to be implemented expect results that need to be passed back
to the caller, so we don't define a separate RPC results structure.
For session validation, the cb_sequence decoding will use a pointer
to the sequence arguments that are part of the RPC argument.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
[define struct nfsd4_cb_sequence here]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Keep the xprt used for create_session in cl_cb_xprt.
Mark cl_callback.cb_minorversion = 1 and remember
the client provided cl_callback.cb_prog rpc program number.
Use it to probe the callback path.
Use the client's network address to initialize as the
callback's address as expected by the xprt creation
routines.
Define xdr sizes and code nfs4_cb_compound header to be able
to send a null callback rpc.
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
[get callback minorversion from fore channel's]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfsd41: change bc_sock to bc_xprt]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[pulled definition for cl_cb_xprt]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfsd41: set up backchannel's cb_addr]
[moved rpc_create_args init to "nfsd: modify nfsd4.1 backchannel to use new xprt class"]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Callbacks are always made using the machine's identity, so we can use a
single auth_generic credential shared among callbacks to all clients and
let the rpc code take care of the rest.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
On setting up the callback to the client, we attempt to use the same
authentication flavor the client did. We find an rpc cred to use by
calling rpcauth_lookup_credcache(), which assumes that the given
authentication flavor has a credentials cache. However, this is not
required to be true--in particular, auth_null does not use one.
Instead, we should call the auth's lookup_cred() method.
Without this, a client attempting to mount using nfsv4 and auth_null
triggers a null dereference.
Cc: stable@kernel.org
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
...rather than as a separate address and port fields. This will be
necessary for implementing callbacks over IPv6. Also, convert
gen_callback to use the standard rpcuaddr2sockaddr routine rather than
its own private one.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Prepare to share backchannel code with NFSv4.1.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
[nfsd41: use nfsd4_cb_sequence for callback minorversion]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Mimic the client and prepare to share the back channel xdr with NFSv4.1.
Bump the number of operations in each encode routine, then backfill the
number of operations.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Move this out of a local variable into the nfs4_delegation object in
preparation for making this an async rpc call (at which point we'll need
any state like this in a common object that's preserved across function
calls).
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
There's no point in keeping this field around--it's always zero.
(Background: the protocol allows you to tell the client that the file is
about to be truncated, as an optimization to save the client from
writing back dirty pages that will just be discarded. We don't
implement this hint. If we do some day, adding this field back in will
be the least of the work involved.)
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The nfs4_cb_recall struct is used only in nfs4_delegation, so its
pointer to the containing delegation is unnecessary--we could just use
container_of().
But there's no real reason to have this a separate struct at all--just
move these fields to nfs4_delegation.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
I want to use the name for a struct that actually does represent a
single callback.
(Actually, I've never been sure it helps to a separate struct for the
callback information. Some day maybe those fields could just be dumped
into struct nfs4_client. I don't know.)
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
We don't really need a synchronous rpc, and moving to an asynchronous
rpc allows us to do without this extra kthread.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The code is a little simpler, and it should be easier to avoid races, if
we just do all rpc client creation/destruction from nfsd or laundromat
threads and do only the rpc calls themselves asynchronously. The rpc
creation doesn't involve any significant waiting (it doesn't call the
client, for example), so there's no reason not to do this.
Also don't bother destroying the client on failure of the rpc null
probe. We may want to retry the probe later anyway.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
We tried to do something overly complicated with the callback rpc
timeouts here. And they're wrong--the result is that by the time a
single callback times out, it's already too late to tell the client
(using the cb_path_down return to RENEW) that the callback is down.
Use a much shorter, simpler timeout.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The errors returned aren't used. Just return 0 and make them available
to a dprintk(). Also, consistently use -ERRNO errors instead of nfs
errors.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Reviewed-by: Benny Halevy <bhalevy@panasas.com>
As part of reducing the scope of the client_mutex, and in order to
remove the need for mutexes from the callback code (so that callbacks
can be done as asynchronous rpc calls), move manipulations of the
file_hashtable under the recall_lock.
Update the relevant comments while we're here.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Alexandros Batsakis <batsakis@netapp.com>
Reviewed-by: Benny Halevy <bhalevy@panasas.com>
Since free_client() is guaranteed to only be called once, and to only
touch the client structure itself (not any common data structures), it
has no need for the state lock.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Alexandros Batsakis <batsakis@netapp.com>
not having the state locked before putting the client/delegation causes a bug.
Also removed the comment from the function header about the state being already locked
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
There's no use for nfs4_cb_null_ops's declaration in fs/nfsd/nfs4callback.c
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This patch adds server-side support for callbacks other than AUTH_SYS.
Signed-off-by: Olga Kornievskaia <aglo@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The rpc client needs to know the principal that the setclientid was done
as, so it can tell gssd who to authenticate to.
Signed-off-by: Olga Kornievskaia <aglo@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
since commit ff7d9756b5
"nfsd: use static memory for callback program and stats"
do_probe_callback uses a static callback program
(NFS4_CALLBACK) rather than the one set in clp->cl_callback.cb_prog
as passed in by the client in setclientid (4.0)
or create_session (4.1).
This patches introduces rpc_create_args.prognumber that allows
overriding program->number when creating rpc_clnt.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Now that cb_stats are static (since commit
ff7d9756b5)
there's no need to clear them.
Initially I thought it might make sense to do
that every callback probing but since the stats
are per-program and they are shared between possibly
several client callback instances, zeroing them out
seems like the wrong thing to do.
Note that that commit also introduced a bug
since stats.program is also being cleared in the process
and it is not restored after the memset as it used to be.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The cl_chatty flag alows us to control whether a given rpc client leaves
"server X not responding, timed out"
messages in the syslog. Such messages make sense for ordinary nfs
clients (where an unresponsive server means applications on the
mountpoint are probably hanging), but not for the callback client (which
can fail more commonly, with the only result just of disabling some
optimizations).
Previously cl_chatty was removed, do to lack of users; reinstate it, and
use it for the nfsd's callback client.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There's no need to dynamically allocate this memory, and doing so may
create the possibility of races on shutdown of the rpc client. (We've
witnessed it only after adding rpcsec_gss support to the server, after
which the rpc code can send destroys calls that expect to still be able
to access the rpc_stats structure after it has been destroyed.)
Such races are in theory possible if the module containing this "static"
memory is removed very quickly after an rpc client is destroyed, but
we haven't seen that happen.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
When the callback channel fails, we inform the client of that by
returning a cb_path_down error the next time it tries to renew its
lease.
If we wait most of a lease period before deciding that a callback has
failed and that the callback channel is down, then we decrease the
chances that the client will find out in time to do anything about it.
So, mark the channel down as soon as we recognize that an rpc has
failed. However, continue trying to recall delegations anyway, in hopes
it will come back up. This will prevent more delegations from being
given out, and ensure cb_path_down is returned to renew calls earlier,
while still making the best effort to deliver recalls of existing
delegations.
Also fix a couple comments and remove a dprink that doesn't seem likely
to be useful.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The whole reason to move this callback-channel probe into a separate
thread was because (for now) we don't have an easy way to create the
rpc_client asynchronously. But I forgot to move the rpc_create() to the
spawned thread. Doh! Fix that.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Our callback code doesn't actually handle concurrent attempts to probe
the callback channel. Some rethinking of the locking may be required.
However, we can also just move the callback probing to this case. Since
this is the only time a client is "confirmed" (and since that can only
happen once in the lifetime of a client), this ensures we only probe
once.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
