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path: root/fs/nfs/nfs4proc.c
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2015-02-18NFSv4.1: Clean up bind_conn_to_sessionTrond Myklebust
We don't need to fake up an entire session in order retrieve the arguments. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-18NFSv4.1: Don't set up a backchannel if the server didn't agree to do soTrond Myklebust
If the server doesn't agree to out backchannel setup request, then don't set one up. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-18NFSv4.1: Clean up create_sessionTrond Myklebust
Don't decode directly into the shared struct session Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-06NFSv4.1: Pin the inode and super block in asynchronous layoutreturnsTrond Myklebust
If we're sending an asynchronous layoutreturn, then we need to ensure that the inode and the super block remain pinned. Cc: Peng Tao <tao.peng@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Reviewed-by: Peng Tao <tao.peng@primarydata.com>
2015-02-06NFSv4.1: Pin the inode and super block in asynchronous layoutcommitTrond Myklebust
If we're sending an asynchronous layoutcommit, then we need to ensure that the inode and the super block remain pinned. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Reviewed-by: Peng Tao <tao.peng@primarydata.com>
2015-02-06NFSv4: Ensure we reference the inode for return-on-close in delegreturnTrond Myklebust
If we have to do a return-on-close in the delegreturn code, then we must ensure that the inode and super block remain referenced. Cc: Peng Tao <tao.peng@primarydata.com> Cc: stable@vger.kernel.org # 3.17.x Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com> Reviewed-by: Peng Tao <tao.peng@primarydata.com>
2015-02-04NFSv4.1: Ask for no delegation on OPEN if using O_DIRECTTrond Myklebust
If we're using NFSv4.1, then we have the ability to let the server know whether or not we believe that returning a delegation as part of our OPEN request would be useful. The feature needs to be used with care, since the client sending the request doesn't necessarily know how other clients are using that file, and how they may be affected by the delegation. For this reason, our initial use of the feature will be to let the server know when the client believes that handing out a delegation would not be useful. The first application for this function is when opening the file using O_DIRECT. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-02-03Merge branch 'flexfiles'Trond Myklebust
* flexfiles: (53 commits) pnfs: lookup new lseg at lseg boundary nfs41: .init_read and .init_write can be called with valid pg_lseg pnfs: Update documentation on the Layout Drivers pnfs/flexfiles: Add the FlexFile Layout Driver nfs: count DIO good bytes correctly with mirroring nfs41: wait for LAYOUTRETURN before retrying LAYOUTGET nfs: add a helper to set NFS_ODIRECT_RESCHED_WRITES to direct writes nfs41: add NFS_LAYOUT_RETRY_LAYOUTGET to layout header flags nfs/flexfiles: send layoutreturn before freeing lseg nfs41: introduce NFS_LAYOUT_RETURN_BEFORE_CLOSE nfs41: allow async version layoutreturn nfs41: add range to layoutreturn args pnfs: allow LD to ask to resend read through pnfs nfs: add nfs_pgio_current_mirror helper nfs: only reset desc->pg_mirror_idx when mirroring is supported nfs41: add a debug warning if we destroy an unempty layout pnfs: fail comparison when bucket verifier not set nfs: mirroring support for direct io nfs: add mirroring support to pgio layer pnfs: pass ds_commit_idx through the commit path ... Conflicts: fs/nfs/pnfs.c fs/nfs/pnfs.h
2015-02-03pnfs/flexfiles: Add the FlexFile Layout DriverTom Haynes
The flexfile layout is a new layout that extends the file layout. It is currently being drafted as a specification at https://datatracker.ietf.org/doc/draft-ietf-nfsv4-layout-types/ Signed-off-by: Weston Andros Adamson <dros@primarydata.com> Signed-off-by: Tom Haynes <loghyr@primarydata.com> Signed-off-by: Tao Peng <bergwolf@primarydata.com>
2015-02-03nfs41: wait for LAYOUTRETURN before retrying LAYOUTGETPeng Tao
Also take care to stop waiting if someone clears retry bit. Signed-off-by: Peng Tao <tao.peng@primarydata.com>
2015-02-03nfs41: introduce NFS_LAYOUT_RETURN_BEFORE_CLOSEPeng Tao
When it is set, generic pnfs would try to send layoutreturn right before last close/delegation_return regard less NFS_LAYOUT_ROC is set or not. LD can then make sure layoutreturn is always sent rather than being omitted. The difference against NFS_LAYOUT_RETURN is that NFS_LAYOUT_RETURN_BEFORE_CLOSE does not block usage of the layout so LD can set it and expect generic layer to try pnfs path at the same time. Signed-off-by: Peng Tao <tao.peng@primarydata.com> Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03nfs41: allow async version layoutreturnPeng Tao
Signed-off-by: Peng Tao <tao.peng@primarydata.com> Signed-off-by: Tom Haynes <loghyr@primarydata.com>
2015-02-03nfs41: clear NFS_LAYOUT_RETURN if layoutreturn is sent or failed to sendPeng Tao
So that pnfs path is not disabled for ever. Signed-off-by: Peng Tao <tao.peng@primarydata.com> Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03nfs41: don't use a layout if it is marked for returningPeng Tao
And if we are to return the same type of layouts, don't bother sending more layoutgets. Signed-off-by: Peng Tao <tao.peng@primarydata.com> Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03nfs4: export nfs4_sequence_donePeng Tao
Signed-off-by: Peng Tao <tao.peng@primarydata.com> Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-02-03nfs4: pass slot table to nfs40_setup_sequencePeng Tao
flexclient needs this as there is no nfs_server to DS connection. Signed-off-by: Peng Tao <tao.peng@primarydata.com> Signed-off-by: Tom Haynes <Thomas.Haynes@primarydata.com>
2015-01-24NFSv4.1: Optimise layout return-on-closeTrond Myklebust
Optimise the layout return on close code by ensuring that 1) Add a check for whether we hold a layout before taking any spinlocks 2) Only take the spin lock once 3) Use nfs_state->state to speed up open file checks Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-01-24NFSv4.1: Allow parallel LOCK/LOCKU callsTrond Myklebust
Note, however, that we still serialise on the open stateid if the lock stateid is unconfirmed. Hopefully that will not prove too much of a burden for first time locks; it should leave the ability to parallelise OPENs unchanged, since they no longer call the serialisation primitives. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-01-24NFSv4: Update of VFS byte range lock must be atomic with the stateid updateTrond Myklebust
Ensure that we test the lock stateid remained unchanged while we were updating the VFS tracking of the byte range lock. Have the process replay the lock to the server if we detect that was not the case. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-01-24NFSv4: Fix lock on-wire reordering issuesTrond Myklebust
This patch ensures that the server cannot reorder our LOCK/LOCKU requests if they are sent in parallel on the wire. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-01-24NFSv4: Always do open_to_lock_owner if the lock stateid is uninitialisedTrond Myklebust
The original text in RFC3530 was terribly confusing since it conflated lockowners and lock stateids. RFC3530bis clarifies that you must use open_to_lock_owner when there is no lock state for that file+lockowner combination. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-01-24NFSv4: Fix atomicity problems with lock stateid updatesTrond Myklebust
When we update the lock stateid, we really do need to ensure that this is done under the state->state_lock, and that we are indeed only updating confirmed locks with a newer version of the same stateid. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-01-24NFSv4.1: Allow parallel OPEN/OPEN_DOWNGRADE/CLOSETrond Myklebust
Remove the serialisation of OPEN/OPEN_DOWNGRADE and CLOSE calls for the case of NFSv4.1 and newer. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-01-24NFSv4: Convert nfs_alloc_seqid() to return an ERR_PTR() if allocation failsTrond Myklebust
When we relax the sequencing on the NFSv4.1 OPEN/CLOSE code, we will want to use the value NULL to indicate that no sequencing is needed. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-01-24NFSv4: More CLOSE/OPEN racesTrond Myklebust
If an OPEN RPC call races with a CLOSE or OPEN_DOWNGRADE so that it updates the nfs_state structure before the CLOSE/OPEN_DOWNGRADE has a chance to do so, then we know that the state->flags need to be recalculated from scratch. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-01-24NFSv4: Fix an atomicity problem in CLOSETrond Myklebust
If we are to remove the serialisation of OPEN/CLOSE, then we need to ensure that the stateid sent as part of a CLOSE operation does not change after we test the state in nfs4_close_prepare. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-01-06NFSv4: Remove incorrect check in can_open_delegated()Trond Myklebust
Remove an incorrect check for NFS_DELEGATION_NEED_RECLAIM in can_open_delegated(). We are allowed to cache opens even in a situation where we're doing reboot recovery. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-01-06NFSv4: Cache the NFSv4/v4.1 client owner_id in the struct nfs_clientTrond Myklebust
Ensure that we cache the NFSv4/v4.1 client owner_id so that we can verify it when we're doing trunking detection. Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-25nfs: Add DEALLOCATE supportAnna Schumaker
This patch adds support for using the NFS v4.2 operation DEALLOCATE to punch holes in a file. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-25nfs: Add ALLOCATE supportAnna Schumaker
This patch adds support for using the NFS v4.2 operation ALLOCATE to preallocate data in a file. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-24nfs41: fix nfs4_proc_layoutget error handlingPeng Tao
nfs4_layoutget_release() drops layout hdr refcnt. Grab the refcnt early so that it is safe to call .release in case nfs4_alloc_pages fails. Signed-off-by: Peng Tao <tao.peng@primarydata.com> Fixes: a47970ff78147 ("NFSv4.1: Hold reference to layout hdr in layoutget") Cc: stable@vger.kernel.org # 3.9+ Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-24nfs: Remove dead case from nfs4_map_errors()Jan Kara
NFS4ERR_ACCESS has number 13 and thus is matched and returned immediately at the beginning of nfs4_map_errors() and there's no point in checking it later. Coverity-id: 733891 Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-12NFSv4: Ensure that we call FREE_STATEID when NFSv4.x stateids are revokedTrond Myklebust
NFSv4.x (x>0) requires us to call TEST_STATEID+FREE_STATEID if a stateid is revoked. We will currently fail to do this if the stateid is a delegation. http://lkml.kernel.org/r/CAN-5tyHwG=Cn2Q9KsHWadewjpTTy_K26ee+UnSvHvG4192p-Xw@mail.gmail.com Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-12NFSv4: Fix races between nfs_remove_bad_delegation() and delegation returnTrond Myklebust
Any attempt to call nfs_remove_bad_delegation() while a delegation is being returned is currently a no-op. This means that we can end up looping forever in nfs_end_delegation_return() if something causes the delegation to be revoked. This patch adds a mechanism whereby the state recovery code can communicate to the delegation return code that the delegation is no longer valid and that it should not be used when reclaiming state. It also changes the return value for nfs4_handle_delegation_recall_error() to ensure that nfs_end_delegation_return() does not reattempt the lock reclaim before state recovery is done. http://lkml.kernel.org/r/CAN-5tyHwG=Cn2Q9KsHWadewjpTTy_K26ee+UnSvHvG4192p-Xw@mail.gmail.com Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-12NFSv4.1: nfs41_clear_delegation_stateid shouldn't trust NFS_DELEGATED_STATETrond Myklebust
This patch removes the assumption made previously, that we only need to check the delegation stateid when it matches the stateid on a cached open. If we believe that we hold a delegation for this file, then we must assume that its stateid may have been revoked or expired too. If we don't test it then our state recovery process may end up caching open/lock state in a situation where it should not. We therefore rename the function nfs41_clear_delegation_stateid as nfs41_check_delegation_stateid, and change it to always run through the delegation stateid test and recovery process as outlined in RFC5661. http://lkml.kernel.org/r/CAN-5tyHwG=Cn2Q9KsHWadewjpTTy_K26ee+UnSvHvG4192p-Xw@mail.gmail.com Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-12NFSv4: Ensure that we remove NFSv4.0 delegations when state has expiredTrond Myklebust
NFSv4.0 does not have TEST_STATEID/FREE_STATEID functionality, so unlike NFSv4.1, the recovery procedure when stateids have expired or have been revoked requires us to just forget the delegation. http://lkml.kernel.org/r/CAN-5tyHwG=Cn2Q9KsHWadewjpTTy_K26ee+UnSvHvG4192p-Xw@mail.gmail.com Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-12NFS: SEEK is an NFS v4.2 featureAnna Schumaker
Somehow the nfs_v4_1_minor_ops had the NFS_CAP_SEEK flag set, enabling SEEK over v4.1. This is wrong, and can make servers crash. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Tested-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-11-05Revert "NFS: nfs4_do_open should add negative results to the dcache."Trond Myklebust
This reverts commit 4fa2c54b5198d09607a534e2fd436581064587ed.
2014-11-05Revert "NFS: remove BUG possibility in nfs4_open_and_get_state"Trond Myklebust
This reverts commit f39c01047994e66e7f3d89ddb4c6141f23349d8d.
2014-09-30Merge branch 'client-4.2' into linux-nextTrond Myklebust
Merge NFSv4.2 client SEEK implementation from Anna * client-4.2: (55 commits) NFS: Implement SEEK NFSD: Implement SEEK NFSD: Add generic v4.2 infrastructure svcrdma: advertise the correct max payload nfsd: introduce nfsd4_callback_ops nfsd: split nfsd4_callback initialization and use nfsd: introduce a generic nfsd4_cb nfsd: remove nfsd4_callback.cb_op nfsd: do not clear rpc_resp in nfsd4_cb_done_sequence nfsd: fix nfsd4_cb_recall_done error handling nfsd4: clarify how grace period ends nfsd4: stop grace_time update at end of grace period nfsd: skip subsequent UMH "create" operations after the first one for v4.0 clients nfsd: set and test NFSD4_CLIENT_STABLE bit to reduce nfsdcltrack upcalls nfsd: serialize nfsdcltrack upcalls for a particular client nfsd: pass extra info in env vars to upcalls to allow for early grace period end nfsd: add a v4_end_grace file to /proc/fs/nfsd lockd: add a /proc/fs/lockd/nlm_end_grace file nfsd: reject reclaim request when client has already sent RECLAIM_COMPLETE nfsd: remove redundant boot_time parm from grace_done client tracking op ...
2014-09-30Merge branch 'bugfixes' into linux-nextTrond Myklebust
* bugfixes: NFSv4.1: Fix an NFSv4.1 state renewal regression NFSv4: fix open/lock state recovery error handling NFSv4: Fix lock recovery when CREATE_SESSION/SETCLIENTID_CONFIRM fails NFS: Fabricate fscache server index key correctly SUNRPC: Add missing support for RPC_CLNT_CREATE_NO_RETRANS_TIMEOUT nfs: fix duplicate proc entries
2014-09-30NFSv4.1: Fix an NFSv4.1 state renewal regressionAndy Adamson
Commit 2f60ea6b8ced ("NFSv4: The NFSv4.0 client must send RENEW calls if it holds a delegation") set the NFS4_RENEW_TIMEOUT flag in nfs4_renew_state, and does not put an nfs41_proc_async_sequence call, the NFSv4.1 lease renewal heartbeat call, on the wire to renew the NFSv4.1 state if the flag was not set. The NFS4_RENEW_TIMEOUT flag is set when "now" is after the last renewal (cl_last_renewal) plus the lease time divided by 3. This is arbitrary and sometimes does the following: In normal operation, the only way a future state renewal call is put on the wire is via a call to nfs4_schedule_state_renewal, which schedules a nfs4_renew_state workqueue task. nfs4_renew_state determines if the NFS4_RENEW_TIMEOUT should be set, and the calls nfs41_proc_async_sequence, which only gets sent if the NFS4_RENEW_TIMEOUT flag is set. Then the nfs41_proc_async_sequence rpc_release function schedules another state remewal via nfs4_schedule_state_renewal. Without this change we can get into a state where an application stops accessing the NFSv4.1 share, state renewal calls stop due to the NFS4_RENEW_TIMEOUT flag _not_ being set. The only way to recover from this situation is with a clientid re-establishment, once the application resumes and the server has timed out the lease and so returns NFS4ERR_BAD_SESSION on the subsequent SEQUENCE operation. An example application: open, lock, write a file. sleep for 6 * lease (could be less) ulock, close. In the above example with NFSv4.1 delegations enabled, without this change, there are no OP_SEQUENCE state renewal calls during the sleep, and the clientid is recovered due to lease expiration on the close. This issue does not occur with NFSv4.1 delegations disabled, nor with NFSv4.0, with or without delegations enabled. Signed-off-by: Andy Adamson <andros@netapp.com> Link: http://lkml.kernel.org/r/1411486536-23401-1-git-send-email-andros@netapp.com Fixes: 2f60ea6b8ced (NFSv4: The NFSv4.0 client must send RENEW calls...) Cc: stable@vger.kernel.org # 3.2.x Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-30NFS: Implement SEEKAnna Schumaker
The SEEK operation is used when an application makes an lseek call with either the SEEK_HOLE or SEEK_DATA flags set. I fall back on nfs_file_llseek() if the server does not have SEEK support. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-25NFSv4: use exponential retry on NFS4ERR_DELAY for async requests.NeilBrown
Currently asynchronous NFSv4 request will be retried with exponential timeout (from 1/10 to 15 seconds), but async requests will always use a 15second retry. Some "async" requests are really synchronous though. The async mechanism is used to allow the request to continue if the requesting process is killed. In those cases, an exponential retry is appropriate. For example, if two different clients both open a file and get a READ delegation, and one client then unlinks the file (while still holding an open file descriptor), that unlink will used the "silly-rename" handling which is async. The first rename will result in NFS4ERR_DELAY while the delegation is reclaimed from the other client. The rename will not be retried for 15 seconds, causing an unlink to take 15 seconds rather than 100msec. This patch only added exponential timeout for async unlink and async rename. Other async calls, such as 'close' are sometimes waited for so they might benefit from exponential timeout too. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-18NFSv4: Fix another bug in the close/open_downgrade codeTrond Myklebust
James Drew reports another bug whereby the NFS client is now sending an OPEN_DOWNGRADE in a situation where it should really have sent a CLOSE: the client is opening the file for O_RDWR, but then trying to do a downgrade to O_RDONLY, which is not allowed by the NFSv4 spec. Reported-by: James Drews <drews@engr.wisc.edu> Link: http://lkml.kernel.org/r/541AD7E5.8020409@engr.wisc.edu Fixes: aee7af356e15 (NFSv4: Fix problems with close in the presence...) Cc: stable@vger.kernel.org # 2.6.33+ Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-12nfs41: change PNFS_LAYOUTRET_ON_SETATTR to only return on truncation to ↵Peng Tao
smaller size Both blocks layout and objects layout want to use it to avoid CB_LAYOUTRECALL but that should only happen if client is doing truncation to a smaller size. For other cases, we let server decide if it wants to recall client's layouts. Change PNFS_LAYOUTRET_ON_SETATTR to follow the logic and not to send layoutreturn unnecessarily. Cc: Christoph Hellwig <hch@lst.de> Cc: Boaz Harrosh <boaz@plexistor.com> Signed-off-by: Peng Tao <tao.peng@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-12pnfs: remove GETDEVICELIST implementationChristoph Hellwig
The current GETDEVICELIST implementation is buggy in that it doesn't handle cursors correctly, and in that it returns an error if the server returns NFSERR_NOTSUPP. Given that there is no actual need for GETDEVICELIST, it has various issues and might get removed for NFSv4.2 stop using it in the blocklayout driver, and thus the Linux NFS client as whole. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-12NFS: remove BUG possibility in nfs4_open_and_get_stateNeilBrown
commit 4fa2c54b5198d09607a534e2fd436581064587ed NFS: nfs4_do_open should add negative results to the dcache. used "d_drop(); d_add();" to ensure that a dentry was hashed as a negative cached entry. This is not safe if the dentry has an non-NULL ->d_inode. It will trigger a BUG_ON in d_instantiate(). In that case, d_delete() is needed. Also, only d_add if the dentry is currently unhashed, it seems pointless removed and re-adding it unchanged. Reported-by: Christoph Hellwig <hch@infradead.org> Fixes: 4fa2c54b5198d09607a534e2fd436581064587ed Cc: Jeff Layton <jeff.layton@primarydata.com> Link: http://lkml.kernel.org/r/20140908144525.GB19811@infradead.org Signed-off-by: NeilBrown <neilb@suse.de> Acked-by: Jeff Layton <jlayton@primarydata.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-10pnfs: retry after a bad stateid error from layoutgetChristoph Hellwig
Currently we fall through to nfs4_async_handle_error when we get a bad stateid error back from layoutget. nfs4_async_handle_error with a NULL state argument will never retry the operations but return the error to higher layer, causing an avoiable fallback to MDS I/O. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2014-09-10NFS: Clear up state owner lock usageAnna Schumaker
can_open_cached() reads values out of the state structure, meaning that we need the so_lock to have a correct return value. As a bonus, this helps clear up some potentially confusing code. Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>