The callback code relies on the fact that much of it is only ever called
from the ordered workqueue callback_wq, and this is worth documenting.
Reported-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When we're destroying the client lease, and we call
nfsd4_shutdown_callback(), we must ensure that we do not return
before all outstanding callbacks have terminated and have
released their payloads.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Move all the cb_holds_slot management into helper functions. No change
in behavior.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
"cb" is never actually NULL in these functions.
On a quick skim of the history, they seem to have been there from the
beginning. I'm not sure if they originally served a purpose.
Reported-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Scott Mayhew revived an old api that communicates with a userspace
daemon to manage some on-disk state that's used to track clients across
server reboots. We've been using a usermode_helper upcall for that, but
it's tough to run those with the right namespaces, so a daemon is much
friendlier to container use cases.
Trond fixed nfsd's handling of user credentials in user namespaces. He
also contributed patches that allow containers to support different sets
of NFS protocol versions.
The only remaining container bug I'm aware of is that the NFS reply
cache is shared between all containers. If anyone's aware of other gaps
in our container support, let me know.
The rest of this is miscellaneous bugfixes.
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Merge tag 'nfsd-5.2' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"This consists mostly of nfsd container work:
Scott Mayhew revived an old api that communicates with a userspace
daemon to manage some on-disk state that's used to track clients
across server reboots. We've been using a usermode_helper upcall for
that, but it's tough to run those with the right namespaces, so a
daemon is much friendlier to container use cases.
Trond fixed nfsd's handling of user credentials in user namespaces. He
also contributed patches that allow containers to support different
sets of NFS protocol versions.
The only remaining container bug I'm aware of is that the NFS reply
cache is shared between all containers. If anyone's aware of other
gaps in our container support, let me know.
The rest of this is miscellaneous bugfixes"
* tag 'nfsd-5.2' of git://linux-nfs.org/~bfields/linux: (23 commits)
nfsd: update callback done processing
locks: move checks from locks_free_lock() to locks_release_private()
nfsd: fh_drop_write in nfsd_unlink
nfsd: allow fh_want_write to be called twice
nfsd: knfsd must use the container user namespace
SUNRPC: rsi_parse() should use the current user namespace
SUNRPC: Fix the server AUTH_UNIX userspace mappings
lockd: Pass the user cred from knfsd when starting the lockd server
SUNRPC: Temporary sockets should inherit the cred from their parent
SUNRPC: Cache the process user cred in the RPC server listener
nfsd: Allow containers to set supported nfs versions
nfsd: Add custom rpcbind callbacks for knfsd
SUNRPC: Allow further customisation of RPC program registration
SUNRPC: Clean up generic dispatcher code
SUNRPC: Add a callback to initialise server requests
SUNRPC/nfs: Fix return value for nfs4_callback_compound()
nfsd: handle legacy client tracking records sent by nfsdcld
nfsd: re-order client tracking method selection
nfsd: keep a tally of RECLAIM_COMPLETE operations when using nfsdcld
nfsd: un-deprecate nfsdcld
...
Stable bugfixes:
- Fall back to MDS if no deviceid is found rather than aborting # v4.11+
- NFS4: Fix v4.0 client state corruption when mount
Features:
- Much improved handling of soft mounts with NFS v4.0
- Reduce risk of false positive timeouts
- Faster failover of reads and writes after a timeout
- Added a "softerr" mount option to return ETIMEDOUT instead of
EIO to the application after a timeout
- Increase number of xprtrdma backchannel requests
- Add additional xprtrdma tracepoints
- Improved send completion batching for xprtrdma
Other bugfixes and cleanups:
- Return -EINVAL when NFS v4.2 is passed an invalid dedup mode
- Reduce usage of GFP_ATOMIC pages in SUNRPC
- Various minor NFS over RDMA cleanups and bugfixes
- Use the correct container namespace for upcalls
- Don't share superblocks between user namespaces
- Various other container fixes
- Make nfs_match_client() killable to prevent soft lockups
- Don't mark all open state for recovery when handling recallable state revoked flag
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Merge tag 'nfs-for-5.2-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client updates from Anna Schumaker:
"Highlights include:
Stable bugfixes:
- Fall back to MDS if no deviceid is found rather than aborting # v4.11+
- NFS4: Fix v4.0 client state corruption when mount
Features:
- Much improved handling of soft mounts with NFS v4.0:
- Reduce risk of false positive timeouts
- Faster failover of reads and writes after a timeout
- Added a "softerr" mount option to return ETIMEDOUT instead of
EIO to the application after a timeout
- Increase number of xprtrdma backchannel requests
- Add additional xprtrdma tracepoints
- Improved send completion batching for xprtrdma
Other bugfixes and cleanups:
- Return -EINVAL when NFS v4.2 is passed an invalid dedup mode
- Reduce usage of GFP_ATOMIC pages in SUNRPC
- Various minor NFS over RDMA cleanups and bugfixes
- Use the correct container namespace for upcalls
- Don't share superblocks between user namespaces
- Various other container fixes
- Make nfs_match_client() killable to prevent soft lockups
- Don't mark all open state for recovery when handling recallable
state revoked flag"
* tag 'nfs-for-5.2-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (69 commits)
SUNRPC: Rebalance a kref in auth_gss.c
NFS: Fix a double unlock from nfs_match,get_client
nfs: pass the correct prototype to read_cache_page
NFSv4: don't mark all open state for recovery when handling recallable state revoked flag
SUNRPC: Fix an error code in gss_alloc_msg()
SUNRPC: task should be exit if encode return EKEYEXPIRED more times
NFS4: Fix v4.0 client state corruption when mount
PNFS fallback to MDS if no deviceid found
NFS: make nfs_match_client killable
lockd: Store the lockd client credential in struct nlm_host
NFS: When mounting, don't share filesystems between different user namespaces
NFS: Convert NFSv2 to use the container user namespace
NFSv4: Convert the NFS client idmapper to use the container user namespace
NFS: Convert NFSv3 to use the container user namespace
SUNRPC: Use namespace of listening daemon in the client AUTH_GSS upcall
SUNRPC: Use the client user namespace when encoding creds
NFS: Store the credential of the mount process in the nfs_server
SUNRPC: Cache cred of process creating the rpc_client
xprtrdma: Remove stale comment
xprtrdma: Update comments that reference ib_drain_qp
...
Instead of having the convention where individual nfsd4_callback_ops->done
operations return -1 to indicate the callback path is down, move the check
to nfsd4_cb_done. Only mark the callback path down on transport-level
errors, not NFS-level errors.
The existing logic causes the server to set SEQ4_STATUS_CB_PATH_DOWN
just because the client returned an error to a CB_RECALL for a
delegation that the client had already done a FREE_STATEID for. But
clearly that error doesn't mean that there's anything wrong with the
backchannel.
Additionally, handle NFS4ERR_DELAY in nfsd4_cb_recall_done. The client
returns NFS4ERR_DELAY if it is already in the process of returning the
delegation.
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When converting kuids to AUTH_UNIX creds, etc we will want to use the
same user namespace as the process that created the rpc client.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The RPC_TASK_KILLED flag should really not be set from another context
because it can clobber data in the struct task when task->tk_flags is
changed non-atomically.
Let's therefore swap out RPC_TASK_KILLED with an atomic flag, and add
a function to set that flag and safely wake up the task.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If there are multiple callbacks queued, waiting for the callback
slot when the callback gets shut down, then they all currently
end up acting as if they hold the slot, and call
nfsd4_cb_sequence_done() resulting in interesting side-effects.
In addition, the 'retry_nowait' path in nfsd4_cb_sequence_done()
causes a loop back to nfsd4_cb_prepare() without first freeing the
slot, which causes a deadlock when nfsd41_cb_get_slot() gets called
a second time.
This patch therefore adds a boolean to track whether or not the
callback did pick up the slot, so that it can do the right thing
in these 2 cases.
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
that could artificially limit NFSv4.1 performance by limiting the number
of oustanding rpcs from a single client. Neil Brown also gets a special
mention for fixing a 14.5-year-old memory-corruption bug in the encoding
of NFSv3 readdir responses.
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Merge tag 'nfsd-5.1' of git://linux-nfs.org/~bfields/linux
Pull NFS server updates from Bruce Fields:
"Miscellaneous NFS server fixes.
Probably the most visible bug is one that could artificially limit
NFSv4.1 performance by limiting the number of oustanding rpcs from a
single client.
Neil Brown also gets a special mention for fixing a 14.5-year-old
memory-corruption bug in the encoding of NFSv3 readdir responses"
* tag 'nfsd-5.1' of git://linux-nfs.org/~bfields/linux:
nfsd: allow nfsv3 readdir request to be larger.
nfsd: fix wrong check in write_v4_end_grace()
nfsd: fix memory corruption caused by readdir
nfsd: fix performance-limiting session calculation
svcrpc: fix UDP on servers with lots of threads
svcrdma: Remove syslog warnings in work completion handlers
svcrdma: Squelch compiler warning when SUNRPC_DEBUG is disabled
svcrdma: Use struct_size() in kmalloc()
svcrpc: fix unlikely races preventing queueing of sockets
svcrpc: svc_xprt_has_something_to_do seems a little long
SUNRPC: Don't allow compiler optimisation of svc_xprt_release_slot()
nfsd: fix an IS_ERR() vs NULL check
This issue is now captured by a trace point in the RPC client.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The get_backchannel_cred() used to return error pointers on error but
now it returns NULL pointers.
Fixes: 97f68c6b02 ("SUNRPC: add 'struct cred *' to auth_cred and rpc_cre")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
SUNRPC has two sorts of credentials, both of which appear as
"struct rpc_cred".
There are "generic credentials" which are supplied by clients
such as NFS and passed in 'struct rpc_message' to indicate
which user should be used to authorize the request, and there
are low-level credentials such as AUTH_NULL, AUTH_UNIX, AUTH_GSS
which describe the credential to be sent over the wires.
This patch replaces all the generic credentials by 'struct cred'
pointers - the credential structure used throughout Linux.
For machine credentials, there is a special 'struct cred *' pointer
which is statically allocated and recognized where needed as
having a special meaning. A look-up of a low-level cred will
map this to a machine credential.
Signed-off-by: NeilBrown <neilb@suse.com>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When NFS creates a machine credential, it is a "generic" credential,
not tied to any auth protocol, and is really just a container for
the princpal name.
This doesn't get linked to a genuine credential until rpcauth_bindcred()
is called.
The lookup always succeeds, so various places that test if the machine
credential is NULL, are pointless.
As a step towards getting rid of generic credentials, this patch gets
rid of generic machine credentials. The nfs_client and rpc_client
just hold a pointer to a constant principal name.
When a machine credential is wanted, a special static 'struct rpc_cred'
pointer is used. rpcauth_bindcred() recognizes this, finds the
principal from the client, and binds the correct credential.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The SUNRPC credential framework was put together before
Linux has 'struct cred'. Now that we have it, it makes sense to
use it.
This first step just includes a suitable 'struct cred *' pointer
in every 'struct auth_cred' and almost every 'struct rpc_cred'.
The rpc_cred used for auth_null has a NULL 'struct cred *' as nothing
else really makes sense.
For rpc_cred, the pointer is reference counted.
For auth_cred it isn't. struct auth_cred are either allocated on
the stack, in which case the thread owns a reference to the auth,
or are part of 'struct generic_cred' in which case gc_base owns the
reference, and "acred" shares it.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: The global callback_cred is no longer used, so it can be
removed.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
I've had trouble when operating a multi-homed Linux NFS server with
Kerberos using NFSv4.0. Lately, I've seen my clients reporting
this (and then hanging):
May 9 11:43:26 manet kernel: NFS: NFSv4 callback contains invalid cred
The client-side commit f11b2a1cfb ("nfs4: copy acceptor name from
context to nfs_client") appears to be related, but I suspect this
problem has been going on for some time before that.
RFC 7530 Section 3.3.3 says:
> For Kerberos V5, nfs/hostname would be a server principal in the
> Kerberos Key Distribution Center database. This is the same
> principal the client acquired a GSS-API context for when it issued
> the SETCLIENTID operation ...
In other words, an NFSv4.0 client expects that the server will use
the same GSS principal for callback that the client used to
establish its lease. For example, if the client used the service
principal "nfs@server.domain" to establish its lease, the server
is required to use "nfs@server.domain" when performing NFSv4.0
callback operations.
The Linux NFS server currently does not. It uses a common service
principal for all callback connections. Sometimes this works as
expected, and other times -- for example, when the server is
accessible via multiple hostnames -- it won't work at all.
This patch scrapes the target name from the client credential,
and uses that for the NFSv4.0 callback credential. That should
be correct much more often.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.
Warning level 2 was used: -Wimplicit-fallthrough=2
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Use enum nfs_cb_opnum4 in decode_cb_op_status. This fixes warnings
seen with clang:
fs/nfsd/nfs4callback.c:451:36: warning: implicit conversion from
enumeration type 'enum nfs_cb_opnum4' to different enumeration
type 'enum nfs_opnum4' [-Wenum-conversion]
status = decode_cb_op_status(xdr, OP_CB_SEQUENCE, &cb->cb_seq_status);
~~~~~~~~~~~~~~~~~~~ ^~~~~~~~~~~~~~
Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The offset of the entry in struct rpc_version has to match the version
number.
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Fixes: 1c5876ddbd ("sunrpc: move p_count out of struct rpc_procinfo")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
struct rpc_procinfo contains function pointers, and marking it as
constant avoids it being able to be used as an attach vector for
code injections.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Trond Myklebust <trond.myklebust@primarydata.com>
p_count is the only writeable memeber of struct rpc_procinfo, which is
a good candidate to be const-ified as it contains function pointers.
This patch moves it into out out struct rpc_procinfo, and into a
separate writable array that is pointed to by struct rpc_version and
indexed by p_statidx.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Declare the p_decode callbacks with the proper prototype instead of
casting to kxdrdproc_t and losing all type safety.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Declare the p_encode callbacks with the proper prototype instead of
casting to kxdreproc_t and losing all type safety.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
The callback tag is NULL, and hdr->nops is unused too right now, but.
But if we were to ever test with a nonzero callback tag, nops will get a
bad value.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The rpccred gotten from rpc_lookup_machine_cred() should be put when
state is shutdown.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
No real change in functionality, but the old interface seems to be
deprecated.
We don't actually care about ordering necessarily, but we do depend on
running at most one work item at a time: nfsd4_process_cb_update()
assumes that no other thread is running it, and that no new callbacks
are starting while it's running.
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Add the encoding/decoding for CB_NOTIFY_LOCK operations.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We already have that info in the client pointer. No need to pass around
a copy.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Also simplify the logic a bit.
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Acked-by: Trond Myklebust <trondmy@primarydata.com>
The rpc client we use to send callbacks may change occasionally. (In
the 4.0 case, the client can use setclientid/setclientid_confirm to
update the callback parameters. In the 4.1+ case, sessions and
connections can come and go.)
The update is done from the callback thread by nfsd4_process_cb_update,
which shuts down the old rpc client and then creates a new one.
The client shutdown kills any ongoing rpc calls. There won't be any new
ones till the new one's created and the callback thread moves on.
When an rpc encounters a problem that may suggest callback rpc's
aren't working any longer, it normally sets NFSD4_CB_DOWN, so the server
can tell the client something's wrong.
But if the rpc notices CB_UPDATE is set, then the failure may just be a
normal result of shutting down the callback client. Or it could just be
a coincidence, but in any case, it means we're runing with the old
about-to-be-discarded client, so the failure's not interesting.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The nfsd4_callback_ops structure is never modified, so declare it as const.
Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
According to Christoph's advice, this patch introduce a new helper
nfsd4_cb_sequence_done() for processing more callback errors, following
the example of the client's nfs41_sequence_done().
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When testing pnfs layout, nfsd got error NFS4ERR_SEQ_MISORDERED.
It is caused by nfs return NFS4ERR_DELAY before validate_seqid(),
don't update the sequnce id, but nfsd updates the sequnce id !!!
According to RFC5661 20.9.3,
" If CB_SEQUENCE returns an error, then the state of the slot
(sequence ID, cached reply) MUST NOT change. "
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
nfsd enters a infinite loop and prints message every 10 seconds:
May 31 18:33:52 test-server kernel: Error sending entire callback!
May 31 18:34:01 test-server kernel: Error sending entire callback!
This is caused by a cb_layoutreturn getting error -10008
(NFS4ERR_DELAY), the client crashing, and then nfsd entering the
infinite loop:
bc_sendto --> call_timeout --> nfsd4_cb_done --> nfsd4_cb_layout_done
with error -10008 --> rpc_delay(task, HZ/100) --> bc_sendto ...
Reproduced using xfstests 074 with nfs client's kdump on,
CONFIG_DEFAULT_HUNG_TASK_TIMEOUT set, and client's blkmapd down:
1. nfs client's write operation will get the layout of file,
and then send getdeviceinfo,
2. but layout segment is not recorded by client because blkmapd is down,
3. client writes data by sending WRITE to server,
4. nfs server recalls the layout of the file before WRITE,
5. network error causes the client reset the session and return NFS4ERR_DELAY,
6. so client's WRITE operation is waiting the reply.
If the task hangs 120s, the client will crash.
7. so that, the next bc_sendto will fail with TIMEOUT,
and cb_status is NFS4ERR_DELAY.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
With sessions in v4.1 or later we don't need to manually probe the backchannel
connection, so we can declare it up instantly after setting up the RPC client.
Note that we really should split nfsd4_run_cb_work in the long run, this is
just the least intrusive fix for now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Checking the rpc_client pointer is not a reliable way to detect
backchannel changes: cl_cb_client is changed only after shutting down
the rpc client, so the condition cl_cb_client = tk_client will always be
true.
Check the RPC_TASK_KILLED flag instead, and rewrite the code to avoid
the buggy cl_callbacks list and fix the lifetime rules due to double
calls of the ->prepare callback operations method for this retry case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We must only increment the sequence id if the client has seen and responded
to a request. If we failed to deliver it to the client we must resend with
the same sequence id. So just like the client track errors at the transport
level differently from those returned in the XDR.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Add support to issue layout recalls to clients. For now we only support
full-file recalls to get a simple and stable implementation. This allows
to embedd a nfsd4_callback structure in the layout_state and thus avoid
any memory allocations under spinlocks during a recall. For normal
use cases that do not intent to share a single file between multiple
clients this implementation is fully sufficient.
To ensure layouts are recalled on local filesystem access each layout
state registers a new FL_LAYOUT lease with the kernel file locking code,
which filesystems that support pNFS exports that require recalls need
to break on conflicting access patterns.
The XDR code is based on the old pNFS server implementation by
Andy Adamson, Benny Halevy, Boaz Harrosh, Dean Hildebrand, Fred Isaman,
Marc Eshel, Mike Sager and Ricardo Labiaga.
Signed-off-by: Christoph Hellwig <hch@lst.de>
The currect code for nfsd41_cb_get_slot() and nfsd4_cb_done() has no
locking in order to guarantee atomicity, and so allows for races of
the form.
Task 1 Task 2
====== ======
if (test_and_set_bit(0) != 0) {
clear_bit(0)
rpc_wake_up_next(queue)
rpc_sleep_on(queue)
return false;
}
This patch breaks the race condition by adding a retest of the bit
after the call to rpc_sleep_on().
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We now have cb_to_delegation and to_delegation, which do the same thing
and are defined separately in different .c files. Move the
cb_to_delegation definition into a header file and eliminate the
redundant to_delegation definition.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Add a higher level abstraction than the rpc_ops for callback operations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Split out initializing the nfs4_callback structure from using it. For
the NULL callback this gets rid of tons of pointless re-initializations.
Note that I don't quite understand what protects us from running multiple
NULL callbacks at the same time, but at least this chance doesn't make
it worse..
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Add a helper to queue up a callback. CB_NULL has a bit of special casing
because it is special in the specification, but all other new callback
operations will be able to share code with this and a few more changes
to refactor the callback code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>