We observed multiple open stateids on the server for files that
seemingly should have been closed.
nfsd4_process_open2() tests for the existence of a preexisting
stateid. If one is not found, the locks are dropped and a new
one is created. The problem is that init_open_stateid(), which
is also responsible for hashing the newly initialized stateid,
doesn't check to see if another open has raced in and created
a matching stateid. This fix is to enable init_open_stateid() to
return the matching stateid and have nfsd4_process_open2()
swap to that stateid and switch to the open upgrade path.
In testing this patch, coverage to the newly created
path indicates that the race was indeed happening.
Signed-off-by: Andrew Elble <aweits@rit.edu>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We've observed the nfsd server in a state where there are
multiple delegations on the same nfs4_file for the same client.
The nfs client does attempt to DELEGRETURN these when they are presented to
it - but apparently under some (unknown) circumstances the client does not
manage to return all of them. This leads to the eventual
attempt to CB_RECALL more than one delegation with the same nfs
filehandle to the same client. The first recall will succeed, but the
next recall will fail with NFS4ERR_BADHANDLE. This leads to the server
having delegations on cl_revoked that the client has no way to FREE
or DELEGRETURN, with resulting inability to recover. The state manager
on the server will continually assert SEQ4_STATUS_RECALLABLE_STATE_REVOKED,
and the state manager on the client will be looping unable to satisfy
the server.
List discussion also reports a race between OPEN and DELEGRETURN that
will be avoided by only sending the delegation once to the
client. This is also logically in accordance with RFC5561 9.1.1 and 10.2.
So, let's:
1.) Not hand out duplicate delegations.
2.) Only send them to the client once.
RFC 5561:
9.1.1:
"Delegations and layouts, on the other hand, are not associated with a
specific owner but are associated with the client as a whole
(identified by a client ID)."
10.2:
"...the stateid for a delegation is associated with a client ID and may be
used on behalf of all the open-owners for the given client. A
delegation is made to the client as a whole and not to any specific
process or thread of control within it."
Reported-by: Eric Meddaugh <etmsys@rit.edu>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Olga Kornievskaia <aglo@umich.edu>
Signed-off-by: Andrew Elble <aweits@rit.edu>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We have a shrinker, we clean out the cache when nfsd is shut down, and
prune the chains on each request. A recurring workqueue job seems like
unnecessary overhead. Just remove it.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Bruce points out that the increment of the seqid in stateids is not
serialized in any way, so it's possible for racing calls to bump it
twice and end up sending the same stateid. While we don't have any
reports of this problem it _is_ theoretically possible, and could lead
to spurious state recovery by the client.
In the current code, update_stateid is always followed by a memcpy of
that stateid, so we can combine the two operations. For better
atomicity, we add a spinlock to the nfs4_stid and hold that when bumping
the seqid and copying the stateid.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
In order to allow the client to make a sane determination of what
happened with racing LAYOUTGET/LAYOUTRETURN/CB_LAYOUTRECALL calls, we
must ensure that the seqids return accurately represent the order of
operations. The simplest way to do that is to ensure that operations on
a single stateid are serialized.
This patch adds a mutex to the layout stateid, and locks it when
checking the layout stateid's seqid. The mutex is held over the entire
operation and released after the seqid is bumped.
Note that in the case of CB_LAYOUTRECALL we must move the increment of
the seqid and setting into a new cb "prepare" operation. The lease
infrastructure will call the lm_break callback with a spinlock held, so
and we can't take the mutex in that codepath.
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
At least in the v4.0 case openowners can hang around for a while after
last close, but they shouldn't really block (for example), a new mount
with a different principal.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
In bakeathon testing Solaris client was getting CLID_INUSE error when
doing a krb5 mount soon after an auth_sys mount, or vice versa.
That's not really necessary since in this case the old client doesn't
have any state any more:
http://tools.ietf.org/html/rfc7530#page-103
"when the server gets a SETCLIENTID for a client ID that
currently has no state, or it has state but the lease has
expired, rather than returning NFS4ERR_CLID_INUSE, the server
MUST allow the SETCLIENTID and confirm the new client ID if
followed by the appropriate SETCLIENTID_CONFIRM."
This doesn't fix the problem completely since our client_has_state()
check counts openowners left around to handle close replays, which we
should probably just remove in this case.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Any file which includes trace.h will need to include state.h, even if
they aren't using any state tracepoints. Ensure that we include any
headers that might be needed in trace.h instead of relying on the
*.c files to have the right ones.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This moves the hole in the struct down below the flags fields, which
allows us to potentially add a new flag without growing the struct.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Remove unneeded NULL test.
The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@ expression x; @@
-if (x != NULL) {
\(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
x = NULL;
-}
// </smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Andrew was seeing a race occur when an OPEN and OPEN_DOWNGRADE were
running in parallel. The server would receive the OPEN_DOWNGRADE first
and check its seqid, but then an OPEN would race in and bump it. The
OPEN_DOWNGRADE would then complete and bump the seqid again. The result
was that the OPEN_DOWNGRADE would be applied after the OPEN, even though
it should have been rejected since the seqid changed.
The only recourse we have here I think is to serialize operations that
bump the seqid in a stateid, particularly when we're given a seqid in
the call. To address this, we add a new rw_semaphore to the
nfs4_ol_stateid struct. We do a down_write prior to checking the seqid
after looking up the stateid to ensure that nothing else is going to
bump it while we're operating on it.
In the case of OPEN, we do a down_read, as the call doesn't contain a
seqid. Those can run in parallel -- we just need to serialize them when
there is a concurrent OPEN_DOWNGRADE or CLOSE.
LOCK and LOCKU however always take the write lock as there is no
opportunity for parallelizing those.
Reported-and-Tested-by: Andrew W Elble <aweits@rit.edu>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Recent Linux clients have started to send GETLAYOUT requests with
minlength less than blocksize.
Servers aren't really allowed to impose this kind of restriction on
layouts; see RFC 5661 section 18.43.3 for details.
This has been observed to cause indefinite hangs on fsx runs on some
clients.
Cc: stable@vger.kernel.org
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Highlights include:
Stable patches:
- Fix atomicity of pNFS commit list updates
- Fix NFSv4 handling of open(O_CREAT|O_EXCL|O_RDONLY)
- nfs_set_pgio_error sometimes misses errors
- Fix a thinko in xs_connect()
- Fix borkage in _same_data_server_addrs_locked()
- Fix a NULL pointer dereference of migration recovery ops for v4.2 client
- Don't let the ctime override attribute barriers.
- Revert "NFSv4: Remove incorrect check in can_open_delegated()"
- Ensure flexfiles pNFS driver updates the inode after write finishes
- flexfiles must not pollute the attribute cache with attrbutes from the DS
- Fix a protocol error in layoutreturn
- Fix a protocol issue with NFSv4.1 CLOSE stateids
Bugfixes + cleanups
- pNFS blocks bugfixes from Christoph
- Various cleanups from Anna
- More fixes for delegation corner cases
- Don't fsync twice for O_SYNC/IS_SYNC files
- Fix pNFS and flexfiles layoutstats bugs
- pnfs/flexfiles: avoid duplicate tracking of mirror data
- pnfs: Fix layoutget/layoutreturn/return-on-close serialisation issues.
- pnfs/flexfiles: error handling retries a layoutget before fallback to MDS
Features:
- Full support for the OPEN NFS4_CREATE_EXCLUSIVE4_1 mode from Kinglong
- More RDMA client transport improvements from Chuck
- Removal of the deprecated ib_reg_phys_mr() and ib_rereg_phys_mr() verbs
from the SUNRPC, Lustre and core infiniband tree.
- Optimise away the close-to-open getattr if there is no cached data
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Merge tag 'nfs-for-4.3-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
Stable patches:
- Fix atomicity of pNFS commit list updates
- Fix NFSv4 handling of open(O_CREAT|O_EXCL|O_RDONLY)
- nfs_set_pgio_error sometimes misses errors
- Fix a thinko in xs_connect()
- Fix borkage in _same_data_server_addrs_locked()
- Fix a NULL pointer dereference of migration recovery ops for v4.2
client
- Don't let the ctime override attribute barriers.
- Revert "NFSv4: Remove incorrect check in can_open_delegated()"
- Ensure flexfiles pNFS driver updates the inode after write finishes
- flexfiles must not pollute the attribute cache with attrbutes from
the DS
- Fix a protocol error in layoutreturn
- Fix a protocol issue with NFSv4.1 CLOSE stateids
Bugfixes + cleanups
- pNFS blocks bugfixes from Christoph
- Various cleanups from Anna
- More fixes for delegation corner cases
- Don't fsync twice for O_SYNC/IS_SYNC files
- Fix pNFS and flexfiles layoutstats bugs
- pnfs/flexfiles: avoid duplicate tracking of mirror data
- pnfs: Fix layoutget/layoutreturn/return-on-close serialisation
issues
- pnfs/flexfiles: error handling retries a layoutget before fallback
to MDS
Features:
- Full support for the OPEN NFS4_CREATE_EXCLUSIVE4_1 mode from
Kinglong
- More RDMA client transport improvements from Chuck
- Removal of the deprecated ib_reg_phys_mr() and ib_rereg_phys_mr()
verbs from the SUNRPC, Lustre and core infiniband tree.
- Optimise away the close-to-open getattr if there is no cached data"
* tag 'nfs-for-4.3-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (108 commits)
NFSv4: Respect the server imposed limit on how many changes we may cache
NFSv4: Express delegation limit in units of pages
Revert "NFS: Make close(2) asynchronous when closing NFS O_DIRECT files"
NFS: Optimise away the close-to-open getattr if there is no cached data
NFSv4.1/flexfiles: Clean up ff_layout_write_done_cb/ff_layout_commit_done_cb
NFSv4.1/flexfiles: Mark the layout for return in ff_layout_io_track_ds_error()
nfs: Remove unneeded checking of the return value from scnprintf
nfs: Fix truncated client owner id without proto type
NFSv4.1/flexfiles: Mark layout for return if the mirrors are invalid
NFSv4.1/flexfiles: RW layouts are valid only if all mirrors are valid
NFSv4.1/flexfiles: Fix incorrect usage of pnfs_generic_mark_devid_invalid()
NFSv4.1/flexfiles: Fix freeing of mirrors
NFSv4.1/pNFS: Don't request a minimal read layout beyond the end of file
NFSv4.1/pnfs: Handle LAYOUTGET return values correctly
NFSv4.1/pnfs: Don't ask for a read layout for an empty file.
NFSv4.1: Fix a protocol issue with CLOSE stateids
NFSv4.1/flexfiles: Don't mark the entire deviceid as bad for file errors
SUNRPC: Prevent SYN+SYNACK+RST storms
SUNRPC: xs_reset_transport must mark the connection as disconnected
NFSv4.1/pnfs: Ensure layoutreturn reserves space for the opaque payload
...
We have observed the server sending recalls for delegation stateids
that have already been successfully returned. Change
nfsd4_cb_recall_done() to return success if the client has returned
the delegation. While this does not completely eliminate the sending
of recalls for delegations that have already been returned, this
does prevent unnecessarily declaring the callback path to be down.
Reported-by: Eric Meddaugh <etmsys@rit.edu>
Signed-off-by: Andrew Elble <aweits@rit.edu>
Acked-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Somebody with a Solaris client was hitting this case. We haven't
figured out why yet, and don't have a reproducer. Meanwhile Frank
noticed that RFC 7530 actually recommends CLID_INUSE for this case.
Unlikely to help the original reporter, but may as well fix it.
Reported-by: Frank Filz <ffilzlnx@mindspring.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
It's possible that a DELEGRETURN could race with (e.g.) client expiry,
in which case we could end up putting the delegation hash reference more
than once.
Have unhash_delegation_locked return a bool that indicates whether it
was already unhashed. In the case of destroy_delegation we only
conditionally put the hash reference if that returns true.
The other callers of unhash_delegation_locked call it while walking
list_heads that shouldn't yet be detached. If we find that it doesn't
return true in those cases, then throw a WARN_ON as that indicates that
we have a partially hashed delegation, and that something is likely very
wrong.
Tested-by: Andrew W Elble <aweits@rit.edu>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When an open or lock stateid is hashed, we take an extra reference to
it. When we unhash it, we drop that reference. The code however does
not properly account for the case where we have two callers concurrently
trying to unhash the stateid. This can lead to list corruption and the
hash reference being put more than once.
Fix this by having unhash_ol_stateid use list_del_init on the st_perfile
list_head, and then testing to see if that list_head is empty before
releasing the hash reference. This means that some of the unhashing
wrappers now become bool return functions so we can test to see whether
the stateid was unhashed before we put the reference.
Reported-by: Andrew W Elble <aweits@rit.edu>
Tested-by: Andrew W Elble <aweits@rit.edu>
Reported-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We can potentially have several nfs4_laundromat jobs running if there
are multiple namespaces running nfsd on the box. Those are effectively
separated from one another though, so I don't see any reason to
serialize them.
Also, create_singlethread_workqueue automatically adds the
WQ_MEM_RECLAIM flag. Since we run this job on a timer, it's not really
involved in any reclaim paths. I see no need for a rescuer thread.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
These messages, combined with the backtrace they trigger, makes it seem
like a serious problem, though a quick search shows distros marking
it as a "won't fix" non-issue when the problem is reported by users.
The backtrace is overkill, and only really manages to show that if
you follow the code path, you can't really avoid it with bootargs
or configuration settings in the container.
Given that, lets tone it down a bit and get rid of the WARN severity,
and the associated backtrace, so people aren't needlessly alarmed.
Also, lets drop the split printk line, since they are grep unfriendly.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Security label can be set in OPEN/CREATE request, nfsd should set
the bitmask in word2 if setting success.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
According to rfc5661 18.16.4,
"If EXCLUSIVE4_1 was used, the client determines the attributes
used for the verifier by comparing attrset with cva_attrs.attrmask;"
So, EXCLUSIVE4_1 also needs those bitmask used to store the verifier.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The encode order should be as the bitmask defined order.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently we'll respond correctly to a request for either
FS_LAYOUT_TYPES or LAYOUT_TYPES, but not to a request for both
attributes simultaneously.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
After commit ae7095a7c4 (nfsd4: helper function for getting mounted_on
ino) we ignore the return value from get_parent_attributes().
Also, the following FATTR4_WORD2_LAYOUT_BLKSIZE uses stat.blksize, so to
avoid overwriting that, use an independent value for the parent's
attributes.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
NLM locks don't conflict with NFSv4 share reservations, so we're not
going to learn anything new by watiting for them.
They do conflict with NFSv4 locks and with delegations.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
export.h refers to the pnfs_layouttype enum, which is defined there.
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Nfsd has implement a site of seq_operations functions as sunrpc's cache.
Just exports sunrpc's codes, and remove nfsd's redundant codes.
v8, same as v6
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Reviewed-by: NeilBrown <neilb@suse.com>
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>
Commit 294ac32e99 "nfsd: protect clid and verifier generation with
client_lock" moved gen_confirm() to gen_clid().
After that commit, setclientid will return a bad reply with all-zero
verifier after copy_clid().
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If using clientid_counter, it seems possible that gen_confirm could
generate the same verifier for the same client in some situations.
Add a new counter for client confirm verifier to make sure gen_confirm
generates a different verifier on each call for the same clientid.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
v2, new helper nfs4_free_stateowner for freeing so_owner.data and sop
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Layout is a state resource, nfsd should check it too.
v2, drop unneeded updating in nfsd4_renew()
v3, fix compile error without CONFIG_NFSD_PNFS
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Add an operation that will do setup of the service. In the case of a
classic thread-based service that means starting up threads. In the case
of a workqueue-based service, the setup will do something different.
Signed-off-by: Shirley Ma <shirley.ma@oracle.com>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Tested-by: Shirley Ma <shirliey.ma@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
For now, all services use svc_xprt_do_enqueue, but once we add
workqueue-based service support, we'll need to do something different.
Signed-off-by: Shirley Ma <shirley.ma@oracle.com>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Tested-by: Shirley Ma <shirley.ma@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
...not technically an operation, but it's more convenient and cleaner
to pass the module pointer in this struct.
Signed-off-by: Shirley Ma <shirley.ma@oracle.com>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Tested-by: Shirley Ma <shirley.ma@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Since we now have a container for holding svc_serv operations, move the
sv_function into it as well.
Signed-off-by: Shirley Ma <shirley.ma@oracle.com>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Tested-by: Shirley Ma <shirley.ma@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
In later patches we'll need to abstract out more operations on a
per-service level, besides sv_shutdown and sv_function.
Declare a new svc_serv_ops struct to hold these operations, and move
sv_shutdown into this struct.
Signed-off-by: Shirley Ma <shirley.ma@oracle.com>
Acked-by: Jeff Layton <jlayton@primarydata.com>
Tested-by: Shirley Ma <shirley.ma@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Andrew Elble
Jeff Layton
J. Bruce Fields
Jeff Layton
Julia Lawall
Christoph Hellwig
Linus Torvalds
Paul Gortmaker
Kinglong Mee
Andreas Gruenbacher
Jeff Layton