When the client is required to use TEST_STATEID to discover which
delegation(s) have been revoked, it may continually test delegations at the
head of the list if the server continues to be unsatisfied and send
SEQ4_STATUS_RECALLABLE_STATE_REVOKED. For a large number of delegations
this behavior is prone to live-lock because the client may never be able to
test and free revoked state at the end of the list since the
SEQ4_STATUS_RECALLABLE_STATE_REVOKED will cause us to flag delegations at
the head of the list to be tested. This problem is further exacerbated by
the state manager's willingness to be scheduled out on a busy system while
testing the list of delegations.
Keep a generation counter for each attempt to test all delegations, and
skip delegations that have already been tested in the current pass.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Torkil Svensgaard <torkil@drcmr.dk>
Tested-by: Ruben Vestergaard <rubenv@drcmr.dk>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
nfs currently doesn't access i_flctx safely. This requires a
smp_load_acquire, as the pointer is set via cmpxchg (a release
operation).
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
If the server reboots while we are engaged in a delegation return, and
there is a pNFS layout with return-on-close set, then the current code
can end up deadlocking in pnfs_roc() when nfs_inode_set_delegation()
tries to return the old delegation.
Now that delegreturn actually uses its own copy of the stateid, it
should be safe to just always update the delegation stateid in place.
Fixes: 078000d02d ("pNFS: We want return-on-close to complete when evicting the inode")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
We mustn't call nfs_wb_all() on anything other than a regular file.
Furthermore, we can exit early when we don't hold a delegation.
Reported-by: David Wysochanski <dwysocha@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When we add support for application level leases and knfsd delegations
to the NFS client, we we want to have them safely underpinned by a
"real" delegation to provide the caching guarantees. If that real
delegation is recalled, then we need to ensure that the application
leases/delegations are recalled too.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If we're unable to immediately recover all locks because the server is
unable to immediately service our reclaim calls, then we want to retry
after we've finished servicing all the other asynchronous delegation
returns on our queue.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
NFS_INO_REVAL_FORCED is intended to tell us that the cache needs
revalidation despite the fact that we hold a delegation. We shouldn't
need to store it anymore, though.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Before referencing the inode, we must ensure that the superblock can be
referenced. Otherwise, we can end up with iput() calling superblock
operations that are no longer valid or accessible.
Fixes: e39d8a186e ("NFSv4: Fix an Oops during delegation callbacks")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When we look up the delegation cred, we are usually doing so in
conjunction with a read of the stateid, and we want to ensure
that the look up is atomic with that read.
Fixes: 57f188e047 ("NFSv4: nfs_update_inplace_delegation() should update delegation cred")
[sfr@canb.auug.org.au: Fixed up borken Fixes: line from Trond :-)]
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Convert nfs_delegation_reap_unclaimed() to use nfs_client_for_each_server()
for efficiency.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Convert it to use the nfs_client_for_each_server() helper, and
make it more efficient by skipping delegations for inodes we
know are in the process of being freed. Also improve the efficiency
of the cursor by skipping delegations that are being freed.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the cred assigned to the delegation that we're updating differs
from the one we're updating too, then we need to update that field
too.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Ensure we don't release the delegation cred during the call to
nfs4_proc_delegreturn().
Fixes: ee05f45677 ("NFSv4: Fix races between open and delegreturn")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The call to nfs_do_return_delegation() needs to be taken without
any RCU locks. Add a refcount to make sure the delegation remains
pinned in memory until we're done.
Fixes: ee05f45677 ("NFSv4: Fix races between open and delegreturn")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If a dentry was not initially looked up while we were holding a
delegation, then we do still need to revalidate that it still holds
the same name. If there are multiple hard links to the same file,
then all the hard links need validation.
Reported-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
[Anna: Put nfs_unset_verifier_delegated() under CONFIG_NFS_V4]
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Delegations can be expensive to return, and can cause scalability issues
for the server. Let's therefore try to limit the number of inactive
delegations we hold.
Once the number of delegations is above a certain threshold, start
to return them on close.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
In order to better manage our delegation caching, add a counter
to track the number of active delegations.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Add a routine to return the delegation immediately upon close of the
file if it was marked for return-on-close.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If a delegation is marked as needing to be returned when the file is
closed, then don't clear that marking until we're ready to return
it.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
In particular, the pnfs return-on-close code will check for that flag,
so ensure we set it appropriately.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If the server returns NFS4ERR_OLD_STATEID in response to our delegreturn,
we want to sync to the most recent seqid for the delegation stateid. However
if we are already at the most recent, we have two possibilities:
- an OPEN reply is still outstanding and will return a new seqid
- an earlier OPEN reply was dropped on the floor due to a timeout.
In the latter case, we may end up unable to complete the delegreturn,
so we want to bump the seqid to a value greater than the cached value.
While this may cause us to lose the delegation in the former case,
it should now be safe to assume that the client will replay the OPEN
if necessary in order to get a new valid stateid.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the server returns the same delegation in an open that we just used
in a delegreturn, we need to ensure we don't apply that stateid if
the delegreturn has freed it on the server.
To do so, we ensure that we do not free the storage for the delegation
until either it is replaced by a new one, or we throw the inode out of
cache.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
In nfs_inode_find_state_and_recover() we want to mark for recovery
only those stateids that match or are older than the supplied
stateid parameter.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Fix the checks in nfs4_inode_make_writeable() to ignore the case where
we hold no delegations. Currently, in such a case, we automatically
flush writes.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the delegation was revoked, or is already being returned, just
clear the NFS_DELEGATION_RETURN and NFS_DELEGATION_RETURN_IF_CLOSED
flags and keep going.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If we revoke a delegation, but the stateid's seqid is newer, then
ensure we update the seqid when marking the delegation as revoked.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the server sent us a new delegation stateid that is more recent than
the one that got revoked, then clear the NFS_DELEGATION_REVOKED flag.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Add a check to ensure that we haven't already removed the delegation
from the inode after we take all the relevant locks.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Rename nfs_inode_return_delegation_noreclaim() to
nfs_inode_evict_delegation(), which better describes what it
does.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If we're processsing a delegation recall, ignore the delegations that
have already been revoked or returned.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
A typo in nfs4_refresh_delegation_stateid() means we're leaking an
RCU lock, and always returning a value of 'false'. As the function
description states, we were always supposed to return 'true' if a
matching delegation was found.
Fixes: 12f275cdd1 ("NFSv4: Retry CLOSE and DELEGRETURN on NFS4ERR_OLD_STATEID.")
Cc: stable@vger.kernel.org # v4.15+
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If the delegation is marked as being revoked, we must not use it
for cached opens.
Fixes: 869f9dfa4d ("NFSv4: Fix races between nfs_remove_bad_delegation() and delegation return")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Fix nfs_reap_expired_delegations() to ensure that we only reap delegations
that are actually expired, rather than triggering on random errors.
Fixes: 45870d6909 ("NFSv4.1: Test delegation stateids when server...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Once we clear the NFS_DELEGATED_STATE flag, we're telling
nfs_delegation_claim_opens() that we're done recovering all open state
for that stateid, so we really need to ensure that we test for all
open modes that are currently cached and recover them before exiting
nfs4_open_delegation_recall().
Fixes: 24311f8841 ("NFSv4: Recovery of recalled read delegations...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: stable@vger.kernel.org # v4.3+
Add SPDX license identifiers to all files which:
- Have no license information of any form
- Have EXPORT_.*_SYMBOL_GPL inside which was used in the
initial scan/conversion to ignore the file
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Only delegations and layouts can be recalled, so it shouldn't be
necessary to recover all opens when handling the status bit
SEQ4_STATUS_RECALLABLE_STATE_REVOKED. We'll still wind up calling
nfs41_open_expired() when a TEST_STATEID returns NFS4ERR_DELEG_REVOKED.
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Reviewed-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Fix a soft lockup when NFS client delegation recovery is attempted
but the inode is in the process of being freed. When the
igrab(inode) call fails, and we have to restart the recovery process,
we need to ensure that we won't attempt to recover the same delegation
again.
Fixes: 45870d6909 ("NFSv4.1: Test delegation stateids when server...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Fix up some compiler warnings about function parameters, etc not being
correctly described or formatted.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.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>
If the server sends a CB_GETATTR or a CB_RECALL while the filesystem is
being unmounted, then we can Oops when releasing the inode in
nfs4_callback_getattr() and nfs4_callback_recall().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Running "./nfstest_delegation --runtest recall26" uncovers that
client doesn't recover the lock when we have an appending open,
where the initial open got a write delegation.
Instead of checking for the passed in open context against
the file lock's open context. Check that the state is the same.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Reduce contention on the inode->i_lock by ensuring that we use RCU
when looking up the NFS open context.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
I was able to reproduce this pretty regularily using xfstests
generic/013 on NFS v4.0.
Reported-by: Ross Zwisler <Ross.Zwisler@linux.intel.com>
Fixes: 6c34265502 (NFSv4: Return NFS4ERR_DELAY when a delegation recall fails due to igrab())
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
