This prepares the removal of the big kernel lock from the
file locking code. We still use the BKL as long as fs/lockd
uses it and ceph might sleep, but we can flip the definition
to a private spinlock as soon as that's done.
All users outside of fs/lockd get converted to use
lock_flocks() instead of lock_kernel() where appropriate.
Based on an earlier patch to use a spinlock from Matthew
Wilcox, who has attempted this a few times before, the
earliest patch from over 10 years ago turned it into
a semaphore, which ended up being slower than the BKL
and was subsequently reverted.
Someone should do some serious performance testing when
this becomes a spinlock, since this has caused problems
before. Using a spinlock should be at least as good
as the BKL in theory, but who knows...
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Sage Weil <sage@newdream.net>
Cc: linux-kernel@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
flock locks want to be labelled using the process pid, while posix locks
want to be labelled using the fl_owner.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This is needed by NFSv4.0 servers in order to keep the number of locking
stateids at a manageable level.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The 'so_delegations' list appears to be unused.
Also eliminate so_client. If we already have so_server, we can get to the
nfs_client structure.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We do not want to have the state recovery thread kick off and wait for a
memory reclaim, since that may deadlock when the writebacks end up
waiting for the state recovery thread to complete.
The safe thing is therefore to use GFP_NOFS in all open, close,
delegation return, lock, etc. operations that may be called by the
state recovery thread.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Ensure that we change the EXCHANGE_ID verifier (i.e. clp->cl_boot_time)
when we want to reset all state. This is mainly needed when the server
tells us that it is revoking our open or lock stateids.
Handle revoking of recallable state by expiring the delegations.
Handle callback path issues by expiring the delegations and then resetting
the session.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Drain the fore channel and reset the max_slots to the new value.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If a KRB5 TGT ticket expires, we don't want to return an error
immediatel. If someone has a long running job and just forgets to run
"kinit" in time then this will make it fail.
Instead, we want to treat this situation as we would NFS4ERR_DELAY and
retry the upcall after delaying a bit with an exponential backoff.
This patch just makes any place that would handle NFS4ERR_DELAY also
handle -EKEYEXPIRED the same way. In the future, we may want to be more
sophisticated however and handle hard vs. soft mounts differently, or
specify some upper limit on how long we'll wait for a new TGT to be
acquired.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Even if the server is crazy, we should be able to mark the stateid as being
bad, to ensure it gets recovered.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Commit 5601a00d67 (nfs: run state manager
in privileged mode) introduces a regression in the NFSv4 code when
compiled with CONFIG_NFS_V4_1. The calls to nfs4_end_drain_session()
from the main loop in nfs4_state_manager() Oops due to the lack of an
NFSv4.1 session when running NFSv4.0.
The fix is to move those two calls back into nfs41_init_clientid() and
nfs4_reset_session().
The calls to nfs4_end_drain_session() that remain inside
nfs4_state_manager() are safe, since the NFSv4.0 code will never set the
NFS4CLNT_SESSION_DRAINING bit.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the CLOSE or OPEN_DOWNGRADE call triggers a state recovery, and has
to be resent, then we must release the seqid. Otherwise the open
recovery will wait for the close to finish, which causes a deadlock.
This is mainly a NFSv4.1 problem, although it can theoretically happen
with NFSv4.0 too, in a OPEN_DOWNGRADE situation.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The NFSv4.1 spec indicates RECLAIM_COMPLETE is to be issued
whenever a client establishes a new client id, not only after
detecting the server has rebooted.
Set the NFS4CLNT_RECLAIM_REBOOT bit after every new client id has
been established. This enables us to issue RECLAIM_COMPLETE
during the wrap up of the NFS4CLNT_RECLAIM_REBOOT state.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The state manager was not marking the stateids as needing to be reclaimed
after reestablishing the clientid.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If CREATE_SESSION fails with NFS4ERR_STALE_CLIENTID, don't clear the
NFS4CLNT_SESSION_DRAINING flag and don't wake RPCs waiting for the
session to be reestablished. We don't have a session yet, so there
is no reason to wake other RPCs.
This avoids sending spurious compounds with bogus sequenceID during
session and state recovery.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
[Trond.Myklebust@netapp.com: cleaned up patch by adding the
nfs41_begin/end_drain_session() helpers]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Move call to get the lease time and the setup of the state
renewal out of nfs4_create_session so that it can be called
after clearing the DRAINING flag. We use the getattr RPC
to obtain the lease time, which requires a sequence slot.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We should not assume that nfs41_init_clientid() will always want to
initialise the session. If it is being called due to a server reboot, then
we just want to reset the session after re-establishing the clientid.
Fix this by getting rid of the 'reset' parameter in
nfs4_proc_create_session(), and instead relying on whether or not the
session slot table pointer is non-NULL.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This patch invokes RECLAIM_COMPLETE after the client is done
reclaiming state.
There are interpretations of the spec that suggest that
RECLAIM_COMPLETE should also be issued after a new clientid
has been obtained from the server and even if there is no
state to reclaim. This tells the server that the client
has no state to reclaim even if the client isn't aware the
server may have rebooted.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Implements RECLAIM_COMPLETE as an asynchronous RPC.
NFS4ERR_DELAY is retried, NFS4ERR_DEADSESSION invokes the error handling
but does not result in a retry, since we don't want to have a lingering
RECLAIM_COMPLETE call sent in the middle of a possible new state recovery
cycle. If a session reset occurs, a new wave of reclaim operations will
follow, containing their own RECLAIM_COMPLETE call. We don't want a
retry to get on the way of recovery by incorrectly indicating to the
server that we're done reclaiming state.
A subsequent patch invokes the functionality.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Otherwise we have no guarantees that other processes won't start another
RPC call while we're resetting the session.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
the server can indicate a number of error conditions by setting the
appropriate bits in the SEQUENCE operation. The client re-establishes
state with the server when it receives one of those, with the action
depending on the specific case.
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Replace sync and async handlers setting of the NFS4CLNT_SESSION_SETUP bit with
setting NFS4CLNT_CHECK_LEASE, and let the state manager decide to reset the session.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the session is reset during state recovery, the state manager thread can
sleep on the slot_tbl_waitq causing a deadlock.
Add a completion framework to the session. Have the state manager thread set
a new session state (NFS4CLNT_SESSION_DRAINING) and wait for the session slot
table to drain.
Signal the state manager thread in nfs41_sequence_free_slot when the
NFS4CLNT_SESSION_DRAINING bit is set and the session is drained.
Reported-by: Trond Myklebust <trond@netapp.com>
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Do not fall through and set NFS4CLNT_SESSION_RESET bit on NFS4ERR_EXPIRED
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The bit is no longer used for session setup, only for session reset.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Reported-by: Trond Myklebust <trond.myklebust@netapp.com>
Resetting the clientid from the state manager could result in not confirming
the clientid due to create session not being called.
Move the create session call from the NFS4CLNT_SESSION_SETUP state manager
initialize session case into the NFS4CLNT_LEASE_EXPIRED case establish_clid
call.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The nfs4_state_manager should not be looking at the error values when
deciding whether or not to loop round in order to handle a higher priority
state recovery task. It should rather be looking at the clp->cl_state.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
nfs4_recovery_handle_error() will correctly handle errors such as
NFS4ERR_CB_PATH_DOWN, however because they are still passed back to the
main loop in nfs4_state_manager(), they can cause the latter to exit
prematurely.
Fix this by letting nfs4_recovery_handle_error() change the error value in
cases where there is no action required by the caller.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In practice, we need to ensure that we call nfs4_state_end_reclaim_reboot
in 2 cases:
- If we lose the lease while we were reclaiming state
OR
- After we're done with reboot recovery
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Commit 76db6d9500 (nfs41: add session setup
to the state manager) introduces an infinite loop possibility in the NFSv4
state manager. By first checking nfs4_has_session() before clearing the
NFS4CLNT_SESSION_SETUP flag, it allows for a situation where someone sets
that flag, but it never gets cleared, and so the state manager loops.
In fact commit c3fad1b1aa (nfs41: add session
reset to state manager) causes this to happen every time we get a network
partition error.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Daniel J Blueman <daniel.blueman@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The oops http://www.kerneloops.org/raw.php?rawid=537858&msgid= appears to
be due to the nfs4_lock_state->ls_state field being uninitialised. This
happens if the call to nfs4_free_lock_state() is triggered at the end of
nfs4_get_lock_state().
The fix is to move the initialisation of ls_state into the allocator.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It is possible for servers to return NFS4ERR_BAD_STATEID when
the state management code is recovering locks or is reclaiming state when
returning a delegation. Ensure that we handle that case.
While we're at it, add in handlers for NFS4ERR_STALE,
NFS4ERR_ADMIN_REVOKED, NFS4ERR_OPENMODE, NFS4ERR_DENIED and
NFS4ERR_STALE_STATEID, since the protocol appears to allow for them too.
Also handle ENOMEM...
Finally, rather than add new NFSv4.0-specific errors and error handling into
the generic delegation code, move that open file and locking state error
handling into the NFSv4 layer.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Unlike minorversion0, in nfsv4.1 the open and lock seqids need
not be incremented by the client and should always be set to zero.
This is implemented using a new nfs_rpc_ops methods -
increment_open_seqid and increment_lock_seqid
Signed-off-by: Rahul Iyer <iyer@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: check for session not minorversion]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Unlike SETCLIENTID, EXCHANGE_ID requires a machine credential. Do not search
for credentials other than the machine credential.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
EXCHANGE_ID has different credential requirements than SETCLIENTID.
Prepare for a separate credential function.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
nfsv4.1 clientid is established via EXCHANGE_ID rather than
SETCLIENTID{,_CONFIRM}
This is implemented using a new establish_clid method in
nfs4_state_recovery_ops.
nfs41: establish clientid via exchange id only if cred != NULL
>From 2.6.26 reclaimer() uses machine cred for setting up the client id
therefore it is never expected to be NULL.
Signed-off-by: Rahul Iyer <iyer@netapp.com>
[removed dprintk]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: lease renewal]
[revamped patch for new nfs4_state_manager design]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Use the machine cred for sending SEQUENCE to renew
the client's lease.
[revamp patch for new state management design starting 2.6.29]
[nfs41: support minorversion 1 for nfs4_check_lease]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: get cred in exchange_id when cred arg is NULL]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: use cl_machined_cred instead of cl_ex_cred]
Since EXCHANGE_ID insists on using the machine credential, cl_ex_cred is
not needed. nfs4_proc_exchange_id() is only called if the machine credential
is available. Remove the credential logic from nfs4_proc_exchange_id.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
