Starting with NFSv4.1, the server is able to deduce the client id from
the SEQUENCE op which means it can always figure out whether or not
the client is holding a delegation on a file that is being changed.
For that reason, RFC5661 does not require a delegation to be unconditionally
recalled on operations such as SETATTR, RENAME, or REMOVE.
Note that for now, we continue to return READ delegations since that is
still expected by the Linux knfsd server.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
For NFS, we just use the "raw" API since the i_version is mostly
managed by the server. The exception there is when the client
holds a write delegation, but we only need to bump it once
there anyway to handle CB_GETATTR.
Tested-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
If we're racing with an OPEN, then retry the operation instead of
declaring it a success.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
[Andrew W Elble: Fix a typo in nfs4_refresh_open_stateid]
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The NFS_INO_REVAL_FORCED flag needs to be set if we just got a delegation,
and we see that there might still be some ambiguity as to whether or not
our attribute or data cache are valid.
In practice, this means that a call to nfs_check_inode_attributes() will
have noticed a discrepancy between cached attributes and measured ones,
so let's move the setting of NFS_INO_REVAL_FORCED to there.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Don't rely on nfs_inode_detach_delegation() succeeding. That can race...
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If we race with a delegreturn before taking the spin lock, we
currently end up dropping the delegation stateid.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Modify the helper nfs_inode_find_state_and_recover() so that it
can check all open/lock/delegation state trackers on that inode for
whether or not they need are affected by a revoked stateid error.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This fixes a potential infinite loop in nfs_reap_expired_delegations.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Ensure that if the server reboots while we're testing and recovering
from revoked delegations, we exit to allow the state manager to
handle matters.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
According to RFC5661, if any of the SEQUENCE status bits
SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED,
SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED, SEQ4_STATUS_ADMIN_STATE_REVOKED,
or SEQ4_STATUS_RECALLABLE_STATE_REVOKED are set, then we need to use
TEST_STATEID to figure out which stateids have been revoked, so we
can acknowledge the loss of state using FREE_STATEID.
While we already do this for open and lock state, we have not been doing
so for all the delegations.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Allow the callers of nfs_remove_bad_delegation() to specify the stateid
that needs to be marked as bad.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
We must not allow the use of delegations that have been revoked or are
being returned.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Fixes: 869f9dfa4d ("NFSv4: Fix races between nfs_remove_bad_delegation()...")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org # v3.19+
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If the delegation is revoked, then it can't be used for caching.
Fixes: 869f9dfa4d ("NFSv4: Fix races between nfs_remove_bad_delegation()...")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org # v3.19+
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When we're using a delegation to represent our open state, we should
ensure that we use the stateid that was used to create that delegation.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When a read delegation is being recalled, and we're reclaiming the
cached opens, we need to make sure that we only reclaim read-only
modes.
A previous attempt to do this, relied on retrieving the delegation
type from the nfs4_opendata structure. Unfortunately, as Kinglong
pointed out, this field can only be set when performing reboot recovery.
Furthermore, if we call nfs4_open_recover(), then we end up clobbering
the state->flags for all modes that we're not recovering...
The fix is to have the delegation recall code pass this information
to the recovery call, and then refactor the recovery code so that
nfs4_open_delegation_recall() does not need to call nfs4_open_recover().
Reported-by: Kinglong Mee <kinglongmee@gmail.com>
Fixes: 39f897fdbd ("NFSv4: When returning a delegation, don't...")
Tested-by: Kinglong Mee <kinglongmee@gmail.com>
Cc: NeilBrown <neilb@suse.com>
Cc: stable@vger.kernel.org # v4.2+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The NFSv4 delegation spec allows the server to tell a client to limit how
much data it cache after the file is closed. In return, the server
guarantees enough free space to avoid ENOSPC situations, etc.
Prior to this patch, we assumed we could always cache aggressively after
close. Unfortunately, this causes problems with servers that set the
limit to 0 and therefore do not offer any ENOSPC guarantees.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Since we're tracking modifications to the page cache on a per-page
basis, it makes sense to express the limit to how much we may cache
in units of pages.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
* bugfixes:
NFSv4: Return delegations synchronously in evict_inode
SUNRPC: Fix a regression when reconnecting
NFS: remount with security change should return EINVAL
nfs: do not export discarded symbols
NFSv4.1: don't export static symbol
Kinglong Mee reports that asynchronous delegations are being killed
by the call to rpc_shutdown_client() when unmounting. This can lead
to state leakage on the server until the client lease expires.
Reported-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Do so on the assumption that for most use cases, that list will turn into
a more or less LRU-ordered list, and so the list traversals in
nfs_client_return_marked_delegations() are likely to be shorter before
hitting a candidate to return.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
In nfs_client_return_marked_delegations() and nfs_delegation_reap_unclaimed()
we want to optimise the loop traversal by skipping delegations that are
already in the process of being returned.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This patch ensures that the superblock doesn't go ahead and disappear
underneath us while the state manager thread is returning delegations.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Ensure that nfs_inode_set_delegation() doesn't inadvertently detach a
delegation that is already in the process of being returned.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Merge cleanups requested by Linus.
* cleanups: (3 commits)
pnfs: Refactor the *_layout_mark_request_commit to use pnfs_layout_mark_request_commit
nfs: Can call nfs_clear_page_commit() instead
nfs: Provide and use helper functions for marking a page as unstable
Highlights incluse:
Features:
- Removing the forced serialisation of open()/close() calls in NFSv4.x (x>0)
makes for a significant performance improvement in metadata intensive
workloads.
- Full support for the pNFS "flexible files" layout type
- Further RPC/RDMA client improvements from Chuck
Bugfixes:
- Stable fix: NFSv4.1 backchannel calls blocking operations with !TASK_RUNNING
- Stable fix: pnfs_generic_pg_init_read/write can be called with lseg == NULL
- Stable fix: Fix an Oopsable condition when nsm_mon_unmon is called as part
of the namespace cleanup,
- Stable fix: Ensure we reference the inode for return-on-close in delegreturn
- Use SO_REUSEPORT to ensure that NFSv3 TCP connections can rebind to the
same source address/port combination during a disconnect/reconnect event.
This is a requirement imposed by most NFSv3 server duplicate reply cache
implementations.
Optimisations:
- Ask for no NFSv4.1 delegations on OPEN if using O_DIRECT
Other:
- Add Anna Schumaker as co-maintainer for the NFS client
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=c47U
-----END PGP SIGNATURE-----
Merge tag 'nfs-for-3.20-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights incluse:
Features:
- Removing the forced serialisation of open()/close() calls in
NFSv4.x (x>0) makes for a significant performance improvement in
metadata intensive workloads.
- Full support for the pNFS "flexible files" layout type
- Further RPC/RDMA client improvements from Chuck
Bugfixes:
- Stable fix: NFSv4.1 backchannel calls blocking operations with !TASK_RUNNING
- Stable fix: pnfs_generic_pg_init_read/write can be called with lseg == NULL
- Stable fix: Fix an Oopsable condition when nsm_mon_unmon is called
as part of the namespace cleanup,
- Stable fix: Ensure we reference the inode for return-on-close in
delegreturn
- Use SO_REUSEPORT to ensure that NFSv3 TCP connections can rebind to
the same source address/port combination during a disconnect/
reconnect event. This is a requirement imposed by most NFSv3
server duplicate reply cache implementations.
Optimisations:
- Ask for no NFSv4.1 delegations on OPEN if using O_DIRECT
Other:
- Add Anna Schumaker as co-maintainer for the NFS client"
* tag 'nfs-for-3.20-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (119 commits)
SUNRPC: Cleanup to remove xs_tcp_close()
pnfs: delete an unintended goto
pnfs/flexfiles: Do not dprintk after the free
SUNRPC: Fix stupid typo in xs_sock_set_reuseport
SUNRPC: Define xs_tcp_fin_timeout only if CONFIG_SUNRPC_DEBUG
SUNRPC: Handle connection reset more efficiently.
SUNRPC: Remove the redundant XPRT_CONNECTION_CLOSE flag
SUNRPC: Make xs_tcp_close() do a socket shutdown rather than a sock_release
SUNRPC: Ensure xs_tcp_shutdown() requests a full close of the connection
SUNRPC: Cleanup to remove remaining uses of XPRT_CONNECTION_ABORT
SUNRPC: Remove TCP socket linger code
SUNRPC: Remove TCP client connection reset hack
SUNRPC: TCP/UDP always close the old socket before reconnecting
SUNRPC: Add helpers to prevent socket create from racing
SUNRPC: Ensure xs_reset_transport() resets the close connection flags
SUNRPC: Do not clear the source port in xs_reset_transport
SUNRPC: Handle EADDRINUSE on connect
SUNRPC: Set SO_REUSEPORT socket option for TCP connections
NFSv4.1: Fix pnfs_put_lseg races
NFSv4.1: pnfs_send_layoutreturn should use GFP_NOFS
...
Ensure that we deal correctly with the case where the server sends us a
newer instance of the same delegation. If the stateids match, but the
sequence numbers differ, then treat the new delegation as if it were
an atomic upgrade.
Signed-off-by: Trond Myklebust <Trond.Myklebust@primarydata.com>
We can now add a dedicated spinlock without expanding struct inode.
Change to using that to protect the various i_flctx lists.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Acked-by: Christoph Hellwig <hch@lst.de>
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>
The clean-up in commit 36281caa83 ended up removing a NULL pointer check
that is needed in order to prevent an Oops in
nfs_async_inode_return_delegation().
Reported-by: "Yan, Zheng" <zheng.z.yan@intel.com>
Link: http://lkml.kernel.org/r/5313E9F6.2020405@intel.com
Fixes: 36281caa83 (NFSv4: Further clean-ups of delegation stateid validation)
Cc: stable@vger.kernel.org # 3.4+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Set up tracepoints to track when delegations are set, reclaimed,
returned by the client, or recalled by the server.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Having a global lock that protects all of this code is a clear
scalability problem. Instead of doing that, move most of the code to be
protected by the i_lock instead. The exceptions are the global lists
that the ->fl_link sits on, and the ->fl_block list.
->fl_link is what connects these structures to the
global lists, so we must ensure that we hold those locks when iterating
over or updating these lists.
Furthermore, sound deadlock detection requires that we hold the
blocked_list state steady while checking for loops. We also must ensure
that the search and update to the list are atomic.
For the checking and insertion side of the blocked_list, push the
acquisition of the global lock into __posix_lock_file and ensure that
checking and update of the blocked_list is done without dropping the
lock in between.
On the removal side, when waking up blocked lock waiters, take the
global lock before walking the blocked list and dequeue the waiters from
the global list prior to removal from the fl_block list.
With this, deadlock detection should be race free while we minimize
excessive file_lock_lock thrashing.
Finally, in order to avoid a lock inversion problem when handling
/proc/locks output we must ensure that manipulations of the fl_block
list are also protected by the file_lock_lock.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The second check was added in commit 65b62a29 but it will never be true.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the state manager thread is already running, we may end up
racing with it in nfs_client_return_marked_delegations. Better to
just allow the state manager thread to do the job.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, if the application that holds the file open isn't doing
I/O, we may end up returning the delegation. This means that we can
no longer cache the file as aggressively, and often also that we
multiply the state that both the server and the client needs to track.
This patch adds a check for open files to the routine that scans
for delegations that are unreferenced.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Add a mutex to the struct nfs4_state_owner to ensure that delegation
recall doesn't conflict with byte range lock removal.
Note that we nest the new mutex _outside_ the state manager reclaim
protection (nfsi->rwsem) in order to avoid deadlocks.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the server reboots while we are converting a delegation into
OPEN/LOCK stateids as part of a delegation return, the current code
will simply exit with an error. This causes us to lose both
delegation state and locking state (i.e. locking atomicity).
Deal with this by exposing the delegation stateid during delegation
return, so that we can recover the delegation, and then resume
open/lock recovery.
Note that not having to hold the nfs_inode->rwsem across the
calls to nfs_delegation_claim_opens() also fixes a deadlock against
the NFSv4.1 reboot recovery code.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Delegations are a v4 feature, so push return_delegation out of the
generic client by creating a new rpc_op and renaming the old function to
be in the nfs v4 "namespace"
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Delegations are a v4 feature, so push them out of the generic code.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Trond Myklebust