Introduce soft connect behavior for UDP transports. In this case, a
major timeout returns ETIMEDOUT instead of EIO.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, if a remote RPC service is unreachable, an RPC ping will
hang until the underlying transport connect attempt times out. A more
desirable behavior might be to have the ping fail immediately so upper
layers can recover appropriately.
In the case of an NFS mount, for instance, this would mean the
mount(2) system call could fail immediately if the server isn't
listening, rather than hanging uninterruptibly for more than 3
minutes.
Change rpc_ping() so that it fails immediately for connection-oriented
transports. rpc_create() will then fail immediately for such
transports if an RPC ping was requested.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Autobinding is handled by the rpciod process, not in user processes
that are generating regular RPC requests. Thus autobinding is usually
not affected by signals targetting user processes, such as KILL or
timer expiration events.
In addition, an RPC request generated by a user process that has
RPC_TASK_SOFTCONN set and needs to perform an autobind will hang if
the remote rpcbind service is not available.
For rpcbind queries on connection-oriented transports, let's use the
new soft connect semantic to return control to the user's process
quickly, if the kernel's rpcbind client can't connect to the remote
rpcbind service.
Logic is introduced in call_bind_status() to handle connection errors
that occurred during an asynchronous rpcbind query. The logic
abandons the rpcbind query if the RPC request has SOFTCONN set, and
retries after a few seconds in the normal case.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The kernel sometimes makes RPC calls to services that aren't running.
Because the kernel's RPC client always assumes the hard retry semantic
when reconnecting a connection-oriented RPC transport, the underlying
reconnect logic takes a long while to time out, even though the remote
may have responded immediately with ECONNREFUSED.
In certain cases, like upcalls to our local rpcbind daemon, or for NFS
mount requests, we'd like the kernel to fail immediately if the remote
service isn't reachable. This allows another transport to be tried
immediately, or the pending request can be abandoned quickly.
Introduce a per-request flag which controls how call_transmit_status()
behaves when request transmission fails because the server cannot be
reached.
We don't want soft connection semantics to apply to other errors. The
default case of the switch statement in call_transmit_status() no
longer falls through; the fall through code is copied to the default
case, and a "break;" is added.
The transport's connection re-establishment timeout is also ignored for
such requests. We want the request to fail immediately, so the
reconnect delay is skipped. Additionally, we don't want a connect
failure here to further increase the reconnect timeout value, since
this request will not be retried.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The success case, where task->tk_status == 0, is by far the most
frequent case in call_transmit_status().
The default: arm of the switch statement in call_transmit_status()
handles the 0 case. default: was moved close to the top of the switch
statement in call_transmit_status() under the theory that the compiler
places object code for the earliest arms of a switch statement first,
making the CPU do less work.
The default: arm of a switch statement, however, is executed only
after all the other cases have been checked. Even if the compiler
rearranges the object code, the default: arm is the "last resort",
meaning all of the other cases have been explicitly exhausted. That
makes the current arrangement about as inefficient as it gets for the
common case.
To fix this, add an explicit check for zero before the switch
statement. That forces the compiler to do the zero check first, no
matter what optimizations it might try to do to the switch statement.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
DOCPROC Documentation/DocBook/networking.xml
Warning(net/sunrpc/clnt.c:647): No description found for parameter 'req'
Warning(net/sunrpc/clnt.c:647): No description found for parameter 'tk_ops'
Warning(net/sunrpc/clnt.c:647): Excess function parameter 'ops' description in 'rpc_run_bc_task'
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Cc: Benny Halevy <bhalevy@panasas.com>
Cc: Andy Adamson <andros@netapp.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: David Miller <davem@davemloft.net>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* 'for-2.6.32' of git://linux-nfs.org/~bfields/linux: (68 commits)
nfsd4: nfsv4 clients should cross mountpoints
nfsd: revise 4.1 status documentation
sunrpc/cache: avoid variable over-loading in cache_defer_req
sunrpc/cache: use list_del_init for the list_head entries in cache_deferred_req
nfsd: return success for non-NFS4 nfs4_state_start
nfsd41: Refactor create_client()
nfsd41: modify nfsd4.1 backchannel to use new xprt class
nfsd41: Backchannel: Implement cb_recall over NFSv4.1
nfsd41: Backchannel: cb_sequence callback
nfsd41: Backchannel: Setup sequence information
nfsd41: Backchannel: Server backchannel RPC wait queue
nfsd41: Backchannel: Add sequence arguments to callback RPC arguments
nfsd41: Backchannel: callback infrastructure
nfsd4: use common rpc_cred for all callbacks
nfsd4: allow nfs4 state startup to fail
SUNRPC: Defer the auth_gss upcall when the RPC call is asynchronous
nfsd4: fix null dereference creating nfsv4 callback client
nfsd4: fix whitespace in NFSPROC4_CLNT_CB_NULL definition
nfsd41: sunrpc: add new xprt class for nfsv4.1 backchannel
sunrpc/cache: simplify cache_fresh_locked and cache_fresh_unlocked.
...
[sunrpc: change idle timeout value for the backchannel]
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This patch fixes the bug that was reported in
http://bugzilla.kernel.org/show_bug.cgi?id=14053
If we're in the case where we need to force a reencode and then resend of
the RPC request, due to xprt_transmit failing with a networking error, then
we _must_ retransmit the entire request.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is still a little wart or two there: Since we've already got a
vfsmount, we might as well pass that in to rpc_create_client_dir.
Another point is that if we open code __rpc_lookup_path() here, then we can
avoid looking up the entire parent directory path over and over again: it
doesn't change.
Also get rid of rpc_clnt->cl_pathname, since it has no users...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This reflects the fact that rpc_mkdir() as it stands today, can only create
a RPC client type directory.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT
This will make hardirq.h inclusion cheaper for every PREEMPT=n config
(which includes allmodconfig/allyesconfig, BTW)
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The 'rq_received' member of 'struct rpc_rqst' is used to track when we
have received a reply to our request. With v4.1, the backchannel
can now accept callback requests over the existing connection. Rename
this field to make it clear that it is only used for tracking reply bytes
and not all bytes received on the connection.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Adds rpc_run_bc_task() which is called by the NFS callback service to
process backchannel requests. It performs similar work to rpc_run_task()
though "schedules" the backchannel task to be executed starting at the
call_trasmit state in the RPC state machine.
It also introduces some miscellaneous updates to the argument validation,
call_transmit, and transport cleanup functions to take into account
that there are now forechannel and backchannel tasks.
Backchannel requests do not carry an RPC message structure, since the
payload has already been XDR encoded using the existing NFSv4 callback
mechanism.
Introduce a new transmit state for the client to reply on to backchannel
requests. This new state simply reserves the transport and issues the
reply. In case of a connection related error, disconnects the transport and
drops the reply. It requires the forechannel to re-establish the connection
and the server to retransmit the request, as stated in NFSv4.1 section
2.9.2 "Client and Server Transport Behavior".
Note: There is no need to loop attempting to reserve the transport. If EAGAIN
is returned by xprt_prepare_transmit(), return with tk_status == 0,
setting tk_action to call_bc_transmit. rpc_execute() will invoke it again
after the task is taken off the sleep queue.
[nfs41: rpc_run_bc_task() need not be exported outside RPC module]
[nfs41: New call_bc_transmit RPC state]
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: Backchannel: No need to loop in call_bc_transmit()]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[rpc_count_iostats incorrectly exits early]
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[Convert rpc_reply_expected() to inline function]
[Remove unnecessary BUG_ON()]
[Rename variable]
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Reading and storing the RPC direction is a three step process.
1. xs_tcp_read_calldir() reads the RPC direction, but it will not store it
in the XDR buffer since the 'struct rpc_rqst' is not yet available.
2. The 'struct rpc_rqst' is obtained during the TCP_RCV_COPY_DATA state.
This state need not necessarily be preceeded by the TCP_RCV_READ_CALLDIR.
For example, we may be reading a continuation packet to a large reply.
Therefore, we can't simply obtain the 'struct rpc_rqst' during the
TCP_RCV_READ_CALLDIR state and assume it's available during TCP_RCV_COPY_DATA.
This patch adds a new TCP_RCV_READ_CALLDIR flag to indicate the need to
read the RPC direction. It then uses TCP_RCV_COPY_CALLDIR to indicate the
RPC direction needs to be saved after the 'struct rpc_rqst' has been allocated.
3. The 'struct rpc_rqst' is obtained by the xs_tcp_read_data() helper
functions. xs_tcp_read_common() then saves the RPC direction in the XDR
buffer if TCP_RCV_COPY_CALLDIR is set. This will happen when we're reading
the data immediately after the direction was read. xs_tcp_read_common()
then clears this flag.
[was nfs41: Skip past the RPC call direction]
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: sunrpc: Add RPC direction back into the XDR buffer]
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: sunrpc: Don't skip past the RPC call direction]
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
While we should definitely return socket errors to the task that is
currently trying to send data, there is no need to propagate the same error
to all the other tasks on xprt->pending. Doing so actually slows down
recovery, since it causes more than one tasks to attempt socket recovery.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If we get an ECONNREFUSED error, we currently go to sleep on the
'xprt->sending' wait queue. The problem is that no timeout is set there,
and there is nothing else that will wake the task up later.
We should deal with ECONNREFUSED in call_status, given that is where we
also deal with -EHOSTDOWN, and friends.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the socket is unconnected, and xprt_transmit() returns ENOTCONN, we
currently give up the lock on the transport channel. Doing so means that
the lock automatically gets assigned to the next task in the xprt->sending
queue, and so that task needs to be woken up to do the actual connect.
The following patch aims to avoid that unnecessary task switch.
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>
Using NIPQUAD() with NIPQUAD_FMT, %d.%d.%d.%d or %u.%u.%u.%u
can be replaced with %pI4
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
If another task is busy in rpcb_getport_async number, it is more efficient
to have it wake us up when it has finished instead of arbitrarily sleeping
for 5 seconds.
Also ensure that rpcb_wake_rpcbind_waiters() is called regardless of
whether or not rpcb_getport_done() gets called.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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>
Clean up: move the logic that displays each task to its own function.
This removes indentation and makes future changes easier.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: don't display the rpc_show_tasks column header unless there is at
least one task to display. As far as I can tell, it is safe to let the
list_for_each_entry macro decide that each list is empty.
scripts/checkpatch.pl also wants a KERN_FOO at the start of any newly added
printk() calls, so this and subsequent patches will also add KERN_INFO.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The RPC client uses a finite state machine to move RPC tasks through each
step of an RPC request. Each state is contained in a function in
net/sunrpc/clnt.c, and named call_foo.
Some of the functions named call_foo have changed over the past few years and
are no longer states in the FSM. These include: call_encode, call_header,
and call_verify. As a clean up, rename the functions that have changed.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Improve debugging messages in call_start() and call_verify() by having
them show the RPC procedure name instead of the procedure number.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The special 'ENOMEM' case that was previously flagged as non-fatal is
bogus: auth_gss always returns EAGAIN for non-fatal errors, and may in fact
return ENOMEM in the special case where xdr_buf_read_netobj runs out of
preallocated buffer space (invariably a _fatal_ error, since there is no
provision for preallocating larger buffers).
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
All errors from call_encode(), with exception of EAGAIN are fatal, so we
should immediately return instead of proceeding to xprt_transmit().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
RFC 2203 requires the server to drop the request if it believes the
RPCSEC_GSS context is out of sequence. The problem is that we have no way
on the client to know why the server dropped the request. In order to avoid
spinning forever trying to resend the request, the safe approach is
therefore to always invalidate the RPCSEC_GSS context on every major
timeout.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFSv4 requires us to ensure that we break the TCP connection before we're
allowed to retransmit a request. However in the case where we're
retransmitting several requests that have been sent on the same
connection, we need to ensure that we don't interfere with the attempt to
reconnect and/or break the connection again once it has been established.
We therefore introduce a 'connection' cookie that is bumped every time a
connection is broken. This allows requests to track if they need to force a
disconnection.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We want to ensure that req->rq_private_buf.len is updated before
req->rq_received, so that call_decode() doesn't use an old value for
req->rq_rcv_buf.len.
In 'call_decode()' itself, instead of using task->tk_status (which is set
using req->rq_received) must use the actual value of
req->rq_private_buf.len when deciding whether or not the received RPC reply
is too short.
Finally ensure that we set req->rq_rcv_buf.len to zero when retrying a
request. A typo meant that we were resetting req->rq_private_buf.len in
call_decode(), and then clobbering that value with the old rq_rcv_buf.len
again in xprt_transmit().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
call_verify() can, under certain circumstances, free the RPC slot. In that
case, our cached pointer 'req = task->tk_rqstp' is invalid. Bug was
introduced in commit 220bcc2afd (SUNRPC:
Don't call xprt_release in call refresh).
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Commit 510deb0d was supposed to move the xprt_create_transport() call in
rpc_create(), but neglected to remove the old call site. This resulted in
a transport leak after every rpc_create() call.
This leak is present in 2.6.24 and 2.6.25.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
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: David S. Miller <davem@davemloft.net>
In all cases where we currently use rpc_wake_up_task(), we almost always
know on which waitqueue the rpc_task is actually sleeping. This will allows
us to simplify the queue locking in a future patch.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
