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path: root/fs/nfsd/nfs4callback.c
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2021-03-11NFSD: fix error handling in NFSv4.0 callbacksOlga Kornievskaia
When the server tries to do a callback and a client fails it due to authentication problems, we need the server to set callback down flag in RENEW so that client can recover. Suggested-by: Bruce Fields <bfields@redhat.com> Signed-off-by: Olga Kornievskaia <kolga@netapp.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Benjamin Coddington <bcodding@redhat.com> Link: https://lore.kernel.org/linux-nfs/FB84E90A-1A03-48B3-8BF7-D9D10AC2C9FE@oracle.com/T/#t
2020-08-23treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-05-28nfsd: Fix svc_xprt refcnt leak when setup callback client failedXiyu Yang
nfsd4_process_cb_update() invokes svc_xprt_get(), which increases the refcount of the "c->cn_xprt". The reference counting issue happens in one exception handling path of nfsd4_process_cb_update(). When setup callback client failed, the function forgets to decrease the refcnt increased by svc_xprt_get(), causing a refcnt leak. Fix this issue by calling svc_xprt_put() when setup callback client failed. Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn> Signed-off-by: Xin Tan <tanxin.ctf@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-05-20NFSD: Add tracepoints for monitoring NFSD callbacksChuck Lever
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-04-17SUNRPC: Fix backchannel RPC soft lockupsChuck Lever
Currently, after the forward channel connection goes away, backchannel operations are causing soft lockups on the server because call_transmit_status's SOFTCONN logic ignores ENOTCONN. Such backchannel Calls are aggressively retried until the client reconnects. Backchannel Calls should use RPC_TASK_NOCONNECT rather than RPC_TASK_SOFTCONN. If there is no forward connection, the server is not capable of establishing a connection back to the client, thus that backchannel request should fail before the server attempts to send it. Commit 58255a4e3ce5 ("NFSD: NFSv4 callback client should use RPC_TASK_SOFTCONN") was merged several years before RPC_TASK_NOCONNECT was available. Because setup_callback_client() explicitly sets NOPING, the NFSv4.0 callback connection depends on the first callback RPC to initiate a connection to the client. Thus NFSv4.0 needs to continue to use RPC_TASK_SOFTCONN. Suggested-by: Trond Myklebust <trondmy@hammerspace.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Cc: <stable@vger.kernel.org> # v4.20+
2019-12-19nfsd: use boottime for lease expiry calculationArnd Bergmann
A couple of time_t variables are only used to track the state of the lease time and its expiration. The code correctly uses the 'time_after()' macro to make this work on 32-bit architectures even beyond year 2038, but the get_seconds() function and the time_t type itself are deprecated as they behave inconsistently between 32-bit and 64-bit architectures and often lead to code that is not y2038 safe. As a minor issue, using get_seconds() leads to problems with concurrent settimeofday() or clock_settime() calls, in the worst case timeout never triggering after the time has been set backwards. Change nfsd to use time64_t and ktime_get_boottime_seconds() here. This is clearly excessive, as boottime by itself means we never go beyond 32 bits, but it does mean we handle this correctly and consistently without having to worry about corner cases and should be no more expensive than the previous implementation on 64-bit architectures. The max_cb_time() function gets changed in order to avoid an expensive 64-bit division operation, but as the lease time is at most one hour, there is no change in behavior. Also do the same for server-to-server copy expiration time. Signed-off-by: Arnd Bergmann <arnd@arndb.de> [bfields@redhat.com: fix up copy expiration] Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-11-08nfsd: document callback_wq serialization of callback codeJ. Bruce Fields
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>
2019-11-08nfsd: mark cb path down on unknown errorsJ. Bruce Fields
An unexpected error is probably a sign that something is wrong with the callback path. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-11-08nfsd: Fix races between nfsd4_cb_release() and nfsd4_shutdown_callback()Trond Myklebust
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>
2019-11-08nfsd: minor 4.1 callback cleanupTrond Myklebust
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>
2019-08-16nfsd: Remove unnecessary NULL checksJ. Bruce Fields
"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>
2019-05-15Merge tag 'nfsd-5.2' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
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 ...
2019-05-09Merge tag 'nfs-for-5.2-1' of git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds
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 ...
2019-05-03nfsd: update callback done processingScott Mayhew
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>
2019-04-26SUNRPC: Cache cred of process creating the rpc_clientTrond Myklebust
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>
2019-04-25SUNRPC: Fix up task signallingTrond Myklebust
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>
2019-04-08nfsd: Don't release the callback slot unless it was actually heldTrond Myklebust
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>
2019-03-12Merge tag 'nfsd-5.1' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
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
2019-02-13NFS: Remove print_overflow_msg()Chuck Lever
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>
2019-02-06nfsd: fix an IS_ERR() vs NULL checkDan Carpenter
The get_backchannel_cred() used to return error pointers on error but now it returns NULL pointers. Fixes: 97f68c6b02e0 ("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>
2018-12-19NFS/NFSD/SUNRPC: replace generic creds with 'struct cred'.NeilBrown
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>
2018-12-19NFS/SUNRPC: don't lookup machine credential until rpcauth_bindcred().NeilBrown
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>
2018-12-19SUNRPC: remove uid and gid from struct auth_credNeilBrown
Use cred->fsuid and cred->fsgid instead. Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2018-12-19SUNRPC: add 'struct cred *' to auth_cred and rpc_credNeilBrown
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>
2018-09-25NFSD CB_OFFLOAD xdrOlga Kornievskaia
Signed-off-by: Olga Kornievskaia <kolga@netapp.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-08-22nfsd: Remove callback_credChuck Lever
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>
2018-08-22nfsd: Use correct credential for NFSv4.0 callback with GSSChuck Lever
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 f11b2a1cfbf5 ("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>
2018-08-09nfsd: Mark expected switch fall-throughGustavo A. R. Silva
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>
2018-04-03nfsd: use correct enum type in decode_cb_op_statusStefan Agner
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>
2017-07-17nfsd: Fix a memory scribble in the callback channelTrond Myklebust
The offset of the entry in struct rpc_version has to match the version number. Reported-by: Dave Jones <davej@codemonkey.org.uk> Fixes: 1c5876ddbdb4 ("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>
2017-05-15nfsd4: const-ify nfs_cb_version4Christoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-05-15sunrpc: mark all struct rpc_procinfo instances as constChristoph Hellwig
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>
2017-05-15sunrpc: move p_count out of struct rpc_procinfoChristoph Hellwig
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>
2017-05-15nfsd: fix decoder callback prototypesChristoph Hellwig
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>
2017-05-15nfsd: fix encoder callback prototypesChristoph Hellwig
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>
2017-02-17nfsd/callback: Drop a useless data copy when comparing sessionidKinglong Mee
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-17nfsd/callback: skip the callback tagKinglong Mee
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>
2017-02-17nfsd/callback: Cleanup callback cred on shutdownKinglong Mee
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>
2016-11-14nfsd: update workqueue creationJ. Bruce Fields
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>
2016-09-26nfsd: plumb in a CB_NOTIFY_LOCK operationJeff Layton
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>
2016-09-16nfsd: eliminate cb_minorversion fieldJeff Layton
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>
2016-06-15nfsd4/rpc: move backchannel create logic into rpc codeJ. Bruce Fields
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>
2015-12-23nfsd: don't base cl_cb_status on stale informationJ. Bruce Fields
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>
2015-11-23nfsd: constify nfsd4_callback_ops structureJulia Lawall
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>
2015-08-13nfsd: New helper nfsd4_cb_sequence_done() for processing more cb errorsKinglong Mee
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>
2015-06-04nfsd: Update callback sequnce id only CB_SEQUENCE successKinglong Mee
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>
2015-06-04nfsd: Reset cb_status in nfsd4_cb_prepare() at retryingKinglong Mee
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>
2015-05-04nfsd: skip CB_NULL probes for 4.1 or laterChristoph Hellwig
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>
2015-05-04nfsd: fix callback restartsChristoph Hellwig
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>
2015-05-04nfsd: split transport vs operation errors for callbacksChristoph Hellwig
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>