06 Jan, 2012
1 commit
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Servers have a finite amount of memory to store NFSv4 open and lock
owners. Moreover, servers may have a difficult time determining when
they can reap their state owner table, thanks to gray areas in the
NFSv4 protocol specification. Thus clients should be careful to reuse
state owners when possible.Currently Linux is not too careful. When a user has closed all her
files on one mount point, the state owner's reference count goes to
zero, and it is released. The next OPEN allocates a new one. A
workload that serially opens and closes files can run through a large
number of open owners this way.When a state owner's reference count goes to zero, slap it onto a free
list for that nfs_server, with an expiry time. Garbage collect before
looking for a state owner. This makes state owners for active users
available for re-use.Now that there can be unused state owners remaining at umount time,
purge the state owner free list when a server is destroyed. Also be
sure not to reclaim unused state owners during state recovery.This change has benefits for the client as well. For some workloads,
this approach drops the number of OPEN_CONFIRM calls from the same as
the number of OPEN calls, down to just one. This reduces wire traffic
and thus open(2) latency. Before this patch, untarring a kernel
source tarball shows the OPEN_CONFIRM call counter steadily increasing
through the test. With the patch, the OPEN_CONFIRM count remains at 1
throughout the entire untar.As long as the expiry time is kept short, I don't think garbage
collection should be terribly expensive, although it does bounce the
clp->cl_lock around a bit.[ At some point we should rationalize the use of the nfs_server
->destroy method. ]Signed-off-by: Chuck Lever
[Trond: Fixed a garbage collection race and a few efficiency issues]
Signed-off-by: Trond Myklebust
05 Jan, 2012
1 commit
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There's no longer a need to check the so_server field in the state
owner, because nowadays the RB tree we search for state owners
contains owners for that only server.Make nfs4_find_state_owners_locked() use the same tree searching logic
as nfs4_insert_state_owner_locked().Signed-off-by: Chuck Lever
Signed-off-by: Trond Myklebust
10 Dec, 2011
1 commit
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There are currently 2 places in the state recovery code, where we do not
take sufficient precautions before accessing the state->lock_states. In
both cases, we should be holding the state->state_lock.Reported-by: Pascal Bouchareine
Signed-off-by: Trond Myklebust
02 Dec, 2011
2 commits
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Currently, the code assumes that the SEQUENCE status bits are mutually
exclusive. They are not...Signed-off-by: Trond Myklebust
Cc: stable@vger.kernel.org [>= 2.6.34] -
If we handled an error condition, then nfs4_recovery_handle_error should
return '0' so that the state recovery thread can continue.
Also ensure that nfs4_check_lease() continues to abort if we haven't got
any credentials by having it return ENOKEY (which is not handled).Signed-off-by: Trond Myklebust
25 Aug, 2011
1 commit
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The NFSv4 spec does not specify that the server must repeat that error,
so in order to avoid having the delegations revoked, we should handle
it immediately.Also note that NFS4ERR_CB_PATH_DOWN does in fact renew the lease...
Signed-off-by: Trond Myklebust
26 Jul, 2011
1 commit
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vfs/nfs: fixup for nfs_open_context change
Signed-off-by: Stephen Rothwell
Signed-off-by: Trond Myklebust
20 Jul, 2011
1 commit
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instead of path_get()/path_put(), we can just use nfs_sb_{,de}active()
to pin the superblock down.Signed-off-by: Al Viro
13 Jul, 2011
1 commit
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can be skipped if the "eir_server_scope" from the exchange_id proc differs from
previous calls.Also, in the future server_scope will be useful for determining whether client
trunking is availableSigned-off-by: Weston Andros Adamson
Signed-off-by: Trond Myklebust
28 May, 2011
1 commit
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Currently, the call to nfs4_schedule_session_recovery() will actually just
result in a test of the lease when what we really want is to force a
session reset.Signed-off-by: Trond Myklebust
Cc: stable@kernel.org
25 Apr, 2011
2 commits
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The following patch ensures that we do not get permanently trapped in
the RPC layer when trying to establish a new client id or session.
This again ensures that the state manager can finish in a timely
fashion when the last filesystem to reference the nfs_client exits.Signed-off-by: Trond Myklebust
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If a server for some reason keeps sending NFS4ERR_DELAY errors, we can end
up looping forever inside nfs4_proc_create_session, and so the usual
mechanisms for detecting if the nfs_client is dead don't work.Fix this by ensuring that we loop inside the nfs4_state_manager thread
instead.Signed-off-by: Trond Myklebust
16 Apr, 2011
1 commit
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Currently, the state manager may continue to try recovering state forever
even after the last filesystem to reference that nfs_client has umounted.Signed-off-by: Trond Myklebust
Cc: stable@kernel.org
29 Mar, 2011
1 commit
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Fix the incorrect use of igrab() inside the i_lock in NFS and Ceph‥
If we are already holding the i_lock, we have a reference to the
inode so we can safely use ihold() to gain an extra reference. This
avoids hangs due to lock recursion on the i_lock now that the
inode_lock is gone and igrab() uses the i_lock itself.Signed-off-by: Dave Chinner
Cc: Al Viro
Cc: linux-fsdevel@vger.kernel.org
Cc: Ryan Mallon
Signed-off-by: Linus Torvalds
12 Mar, 2011
4 commits
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Use our own async error handler.
Mark the layout as failed and retry i/o through the MDS on specified errors.Update the mds_offset in nfs_readpage_retry so that a failed short-read retry
to a DS gets correctly resent through the MDS.Signed-off-by: Andy Adamson
Signed-off-by: Trond Myklebust -
Data servers cannot send nfs4_proc_get_lease_time. but still need to setup
state renewal. Add the NFS_CS_CHECK_LEASE_TIME bit to indicate if the lease
time can be checked.Signed-off-by: Andy Adamson
Signed-off-by: Trond Myklebust -
There are no more external users of nfs4_state_mark_reclaim_nograce() or
nfs4_state_mark_reclaim_reboot(), so mark them as static.Signed-off-by: Trond Myklebust
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nfs4_schedule_state_recovery() should only be used when we need to force
the state manager to check the lease. If we just want to start the
state manager in order to handle a state recovery situation, we should be
using nfs4_schedule_state_manager().This patch fixes the abuses of nfs4_schedule_state_recovery() by replacing
its use with a set of helper functions that do the right thing.Signed-off-by: Trond Myklebust
26 Jan, 2011
1 commit
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The information required to find the nfs_client cooresponding to the incoming
back channel request is contained in the NFS layer. Perform minimal checking
in the RPC layer pg_authenticate method, and push more detailed checking into
the NFS layer where the nfs_client can be found.Signed-off-by: Andy Adamson
Signed-off-by: Trond Myklebust
07 Jan, 2011
4 commits
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NFSv4 migration needs to reassociate state owners from the source to
the destination nfs_server data structures. To make that easier, move
the cl_state_owners field to the nfs_server struct. cl_openowner_id
and cl_lockowner_id accompany this move, as they are used in
conjunction with cl_state_owners.The cl_lock field in the parent nfs_client continues to protect all
three of these fields.Signed-off-by: Chuck Lever
Signed-off-by: Trond Myklebust -
A layout can request return-on-close. How this interacts with the
forgetful model of never sending LAYOUTRETURNS is a bit ambiguous.
We forget any layouts marked roc, and wait for them to be completely
forgotten before continuing with the close. In addition, to compensate
for races with any inflight LAYOUTGETs, and the fact that we do not get
any layout stateid back from the server, we set the barrier to the worst
case scenario of current_seqid + number of outstanding LAYOUTGETS.Signed-off-by: Fred Isaman
Signed-off-by: Trond Myklebust -
Currently session draining only drains the fore channel.
The back channel processing must also be drained.Use the back channel highest_slot_used to indicate that a callback is being
processed by the callback thread. Move the session complete to be per channel.When the session is draininig, wait for any current back channel processing
to complete and stop all new back channel processing by returning NFS4ERR_DELAY
to the back channel client.Drain the back channel, then the fore channel.
Signed-off-by: Andy Adamson
Signed-off-by: Trond Myklebust -
The sessions based callback service is started prior to the CREATE_SESSION call
so that it can handle CB_NULL requests which can be sent before the
CREATE_SESSION call returns and the session ID is known.Set the callback sessionid after a sucessful CREATE_SESSION.
Signed-off-by: Andy Adamson
Signed-off-by: Trond Myklebust
27 Oct, 2010
1 commit
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* 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
net/sunrpc: Use static const char arrays
nfs4: fix channel attribute sanity-checks
NFSv4.1: Use more sensible names for 'initialize_mountpoint'
NFSv4.1: pnfs: filelayout: add driver's LAYOUTGET and GETDEVICEINFO infrastructure
NFSv4.1: pnfs: add LAYOUTGET and GETDEVICEINFO infrastructure
NFS: client needs to maintain list of inodes with active layouts
NFS: create and destroy inode's layout cache
NFSv4.1: pnfs: filelayout: introduce minimal file layout driver
NFSv4.1: pnfs: full mount/umount infrastructure
NFS: set layout driver
NFS: ask for layouttypes during v4 fsinfo call
NFS: change stateid to be a union
NFSv4.1: pnfsd, pnfs: protocol level pnfs constants
SUNRPC: define xdr_decode_opaque_fixed
NFSD: remove duplicate NFS4_STATEID_SIZE
26 Oct, 2010
1 commit
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* 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (67 commits)
SUNRPC: Cleanup duplicate assignment in rpcauth_refreshcred
nfs: fix unchecked value
Ask for time_delta during fsinfo probe
Revalidate caches on lock
SUNRPC: After calling xprt_release(), we must restart from call_reserve
NFSv4: Fix up the 'dircount' hint in encode_readdir
NFSv4: Clean up nfs4_decode_dirent
NFSv4: nfs4_decode_dirent must clear entry->fattr->valid
NFSv4: Fix a regression in decode_getfattr
NFSv4: Fix up decode_attr_filehandle() to handle the case of empty fh pointer
NFS: Ensure we check all allocation return values in new readdir code
NFS: Readdir plus in v4
NFS: introduce generic decode_getattr function
NFS: check xdr_decode for errors
NFS: nfs_readdir_filler catch all errors
NFS: readdir with vmapped pages
NFS: remove page size checking code
NFS: decode_dirent should use an xdr_stream
SUNRPC: Add a helper function xdr_inline_peek
NFS: remove readdir plus limit
...
25 Oct, 2010
1 commit
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In particular, server reboot will invalidate all layouts.
Note that in order to have an active layout, we must get a successful response
from the server. To avoid adding that machinery, this patch just includes a
stub that fakes up a successful return. Since the layout is never referenced
for io, this is not a problem.Signed-off-by: Andy Adamson
Signed-off-by: Benny Halevy
Signed-off-by: Dean Hildebrand
Signed-off-by: Fred Isaman
Signed-off-by: Trond Myklebust
24 Oct, 2010
2 commits
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nfs4state.c uses interfaces from ratelimit.h. It needs to include
that header file to fix build errors:fs/nfs/nfs4state.c:1195: warning: type defaults to 'int' in declaration of 'DEFINE_RATELIMIT_STATE'
fs/nfs/nfs4state.c:1195: warning: parameter names (without types) in function declaration
fs/nfs/nfs4state.c:1195: error: invalid storage class for function 'DEFINE_RATELIMIT_STATE'
fs/nfs/nfs4state.c:1195: error: implicit declaration of function '__ratelimit'
fs/nfs/nfs4state.c:1195: error: '_rs' undeclared (first use in this function)Signed-off-by: Randy Dunlap
Cc: Trond Myklebust
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Trond Myklebust -
Otherwise, we cannot recover state correctly.
Signed-off-by: Trond Myklebust
20 Oct, 2010
1 commit
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If the server sends us an NFS4ERR_STALE_CLIENTID while the state management
thread is busy reclaiming state, we do want to treat all state that wasn't
reclaimed before the STALE_CLIENTID as if a network partition occurred (see
the edge conditions described in RFC3530 and RFC5661).
What we do not want to do is to send an nfs4_reclaim_complete(), since we
haven't yet even started reclaiming state after the server rebooted.Signed-off-by: Trond Myklebust
Cc: stable@kernel.org
05 Oct, 2010
1 commit
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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
Acked-by: Matthew Wilcox
Cc: Christoph Hellwig
Cc: Trond Myklebust
Cc: "J. Bruce Fields"
Cc: Andrew Morton
Cc: Miklos Szeredi
Cc: Frederic Weisbecker
Cc: Ingo Molnar
Cc: John Kacur
Cc: Sage Weil
Cc: linux-kernel@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
31 Jul, 2010
2 commits
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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
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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
25 Jun, 2010
1 commit
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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
23 Jun, 2010
2 commits
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Signed-off-by: Trond Myklebust
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Signed-off-by: Trond Myklebust
15 May, 2010
2 commits
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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
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Reviewed-by: Chuck Lever
Signed-off-by: Trond Myklebust
03 Mar, 2010
1 commit
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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
10 Feb, 2010
2 commits
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Signed-off-by: Andy Adamson
Signed-off-by: Trond Myklebust -
Drain the fore channel and reset the max_slots to the new value.
Signed-off-by: Andy Adamson
Signed-off-by: Trond Myklebust