Commit graph

179 commits

Author SHA1 Message Date
Trond Myklebust
9c00fd9acb NFSv4: Charge NFSv4 open state trackers to kmemcg
Allow kmemcg to limit the number of NFSv4 delegation, lock and open
state trackers.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2022-02-25 18:50:12 -05:00
Trond Myklebust
6e176d4716 NFSv4: Fixes for nfs4_inode_return_delegation()
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>
2021-10-20 18:09:53 -04:00
Trond Myklebust
6b4befc0a0 NFSv4: Add lease breakpoints in case of a delegation recall or return
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>
2021-06-13 19:36:28 -04:00
Trond Myklebust
be20037725 NFSv4: Fix delegation return in cases where we have to retry
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>
2021-06-13 19:36:27 -04:00
Trond Myklebust
cc7f2dae63 NFS: Don't store NFS_INO_REVAL_FORCED
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>
2021-04-14 09:36:29 -04:00
Trond Myklebust
6453bcd0d8 NFS: Fix up incorrect documentation
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2021-04-05 09:04:20 -04:00
Trond Myklebust
113aac6d56 NFS: nfs_delegation_find_inode_server must first reference the superblock
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operations that are no longer valid or accessible.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>
2021-01-10 16:29:28 -05:00
Trond Myklebust
fc51b1cf39 NFS: Beware when dereferencing the delegation cred
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>
2020-04-03 18:26:02 -04:00
Trond Myklebust
7f156ef0bf NFSv4: Clean up nfs_delegation_reap_expired()
Convert to use nfs_client_for_each_server() for efficiency.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-16 08:34:30 -04:00
Trond Myklebust
1bba38b283 NFSv4: Clean up nfs_delegation_reap_unclaimed()
Convert nfs_delegation_reap_unclaimed() to use nfs_client_for_each_server()
for efficiency.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2020-03-16 08:34:30 -04:00
Trond Myklebust
af3b61bf61 NFSv4: Clean up nfs_client_return_marked_delegations()
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>
2020-03-16 08:34:30 -04:00
Trond Myklebust
57f188e047 NFSv4: nfs_update_inplace_delegation() should update delegation cred
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>
2020-03-16 08:34:28 -04:00
Trond Myklebust
5d63944f82 NFSv4: Ensure the delegation cred is pinned when we call delegreturn
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>
2020-02-13 16:23:02 -05:00
Trond Myklebust
8c75593c6e NFSv4: Ensure the delegation is pinned in nfs_do_return_delegation()
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>
2020-02-13 16:18:50 -05:00
Trond Myklebust
efeda80da3 NFSv4: Fix revalidation of dentries with delegations
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>
2020-02-12 13:55:25 -05:00
Trond Myklebust
10717f4563 NFSv4: Limit the total number of cached delegations
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>
2020-02-03 16:35:07 -05:00
Trond Myklebust
d2269ea14e NFSv4: Add accounting for the number of active delegations held
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>
2020-02-03 16:35:07 -05:00
Trond Myklebust
b7b7dac684 NFSv4: Try to return the delegation immediately when marked for return on close
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>
2020-02-03 16:35:07 -05:00
Trond Myklebust
0d10416797 NFS: Clear NFS_DELEGATION_RETURN_IF_CLOSED when the delegation is returned
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>
2020-02-03 16:35:07 -05:00
Trond Myklebust
f885ea640d NFSv4: nfs_inode_evict_delegation() should set NFS_DELEGATION_RETURNING
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>
2020-02-03 16:35:07 -05:00
Trond Myklebust
246afc0aa5 NFSv4: Handle NFS4ERR_OLD_STATEID in delegreturn
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>
2019-11-03 21:28:46 -05:00
Trond Myklebust
ee05f45677 NFSv4: Fix races between open and delegreturn
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>
2019-11-03 21:28:46 -05:00
Trond Myklebust
42c304c34e NFS: nfs_inode_find_state_and_recover() fix stateid matching
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>
2019-11-03 21:28:46 -05:00
Trond Myklebust
3887ce1aac NFSv4: Fix nfs4_inode_make_writeable()
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>
2019-11-03 21:28:46 -05:00
Trond Myklebust
1deed57235 NFSv4: Don't reclaim delegations that have been returned or revoked
If the delegation has already been revoked, we want to avoid reclaiming
it on reboot.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-11-03 21:28:46 -05:00
Trond Myklebust
af20b7b850 NFSv4: Ignore requests to return the delegation if it was revoked
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>
2019-11-03 21:28:46 -05:00
Trond Myklebust
d51f91d262 NFSv4: Revoke the delegation on success in nfs4_delegreturn_done()
If the delegation was successfully returned, then mark it as revoked.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-11-03 21:28:46 -05:00
Trond Myklebust
f2d47b5502 NFSv4: Update the stateid seqid in nfs_revoke_delegation()
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>
2019-11-03 21:28:46 -05:00
Trond Myklebust
ae084a32ee NFSv4: Clear the NFS_DELEGATION_REVOKED flag in nfs_update_inplace_delegation()
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>
2019-11-03 21:28:45 -05:00
Trond Myklebust
e0f07896af NFSv4: Hold the delegation spinlock when updating the seqid
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-11-03 21:28:45 -05:00
Trond Myklebust
f9e0cc9c97 NFSv4: Don't remove the delegation from the super_list more than once
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>
2019-11-03 21:28:45 -05:00
Trond Myklebust
b47e0e478c NFS: Rename nfs_inode_return_delegation_noreclaim()
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>
2019-11-03 21:28:45 -05:00
Trond Myklebust
b57562087b NFSv4: fail nfs4_refresh_delegation_stateid() when the delegation was revoked
If the delegation was revoked, we don't want to retry the delegreturn.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-11-03 21:28:45 -05:00
Trond Myklebust
457a50424b NFSv4: Delegation recalls should not find revoked delegations
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>
2019-11-03 21:28:45 -05:00
Trond Myklebust
79cc55422c NFS: Fix an RCU lock leak in nfs4_refresh_delegation_stateid()
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>
2019-11-01 11:03:56 -04:00
Trond Myklebust
be3df3dd4c NFSv4: Don't allow a cached open with a revoked delegation
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>
2019-11-01 10:59:26 -04:00
Trond Myklebust
ad11408970 NFSv4.1: Only reap expired delegations
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>
2019-08-04 22:35:40 -04:00
Trond Myklebust
5eb8d18ca0 NFSv4: Fix delegation state recovery
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+
2019-08-04 22:35:40 -04:00
Thomas Gleixner
457c899653 treewide: Add SPDX license identifier for missed files
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>
2019-05-21 10:50:45 +02:00
Scott Mayhew
8ca017c8ce NFSv4: don't mark all open state for recovery when handling recallable state revoked flag
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>
2019-05-09 16:26:57 -04:00
Trond Myklebust
6f9449be53 NFS: Fix a soft lockup in the delegation recovery code
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>
2019-02-21 14:51:25 -05:00
Trond Myklebust
302fad7bd5 NFS: Fix up documentation warnings
Fix up some compiler warnings about function parameters, etc not being
correctly described or formatted.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2019-02-20 15:14:21 -05:00
NeilBrown
a52458b48a NFS/NFSD/SUNRPC: replace generic creds with 'struct cred'.
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>
2018-12-19 13:52:46 -05:00
Trond Myklebust
e39d8a186e NFSv4: Fix an Oops during delegation callbacks
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>
2018-11-13 17:15:17 -05:00
Olga Kornievskaia
44f411c353 NFSv4.x: fix lock recovery during delegation recall
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>
2018-10-05 09:34:36 -04:00
Trond Myklebust
0de43976fb NFS: Convert lookups of the open context to RCU
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>
2018-09-30 15:35:17 -04:00
Anna Schumaker
d5681f59ee NFS: Fix an rcu deadlock in nfs_delegation_find_inode()
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>
2018-06-14 14:05:38 -04:00
Trond Myklebust
6c34265502 NFSv4: Return NFS4ERR_DELAY when a delegation recall fails due to igrab()
If the attempt to recall the delegation fails because the inode is
in the process of being evicted from cache, then use NFS4ERR_DELAY
to ask the server to retry later.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-06-08 16:36:10 -04:00
Trond Myklebust
97c2c17af9 NFSv4: Ensure the inode is clean when we set a delegation
If there are attributes that are still invalid when we set a delegation,
then we need to set the NFS_INO_REVAL_FORCED flag.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-06-04 15:03:58 -04:00
NeilBrown
e04bbf6b1b NFS: Avoid quadratic search when freeing delegations.
There are three places that walk all delegation for an nfs_client and
restart whenever they find something interesting - potentially
resulting in a quadratic search:  If there are 10,000 uninteresting
delegations followed by 10,000 interesting one, then the code
skips over 100,000,000 delegations, which can take a noticeable amount
of time.

Of these nfs_delegation_reap_unclaimed() and
nfs_reap_expired_delegations() are only called during unusual events:
a server reboots or reports expired delegations, probably due to a
network partition.  Optimizing these is not particularly important.

The third, nfs_client_return_marked_delegations(), is called
periodically via nfs_expire_unreferenced_delegations().  It could
cause periodic problems on a busy server.

New delegations are added to the end of the list, so if there are
10,000 open files with delegations, and 10,000 more recently opened files
that received delegations but are now closed, then
nfs_client_return_marked_delegations() can take seconds to skip over
the 10,000 open files 10,000 times.  That is a waste of time.

The avoid this waste a place-holder (an inode) is kept when locks are
dropped, so that the place can usually be found again after taking
rcu_readlock().  This place holder ensure that we find the right
starting point in the list of nfs_servers, and makes is probable that
we find the right starting point in the list of delegations.
We might need to occasionally restart at the head of that list.

It might be possible that the place_holder inode could lose its
delegation separately, and then get a new one using the same (freed
and then reallocated) 'struct nfs_delegation'.  Were this to happen,
the new delegation would be at the end of the list and we would miss
returning some other delegations.  This would have the effect of
unnecessarily delaying the return of some unused delegations until the
next time this function is called - typically 90 seconds later.  As
this is not a correctness issue and is vanishingly unlikely to happen,
it does not seem worth addressing.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
2018-05-31 15:02:14 -04:00