The iscsi_ibft.c changes are almost certainly a bugfix as the
pointer 'ip' is a u8 *, so they never print the last 8 bytes
of the IPv6 address, and the eight bytes they do print have
a zero byte with them in each 16-bit word.
Other than that, this should cause no difference in functionality.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Clean up: Now that lockd_up() starts listeners for both transports, the
"proto" argument is no longer needed.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Commit 24e36663, which first appeared in 2.6.19, changed lockd so that
the client side starts a UDP listener only if there is a UDP NFSv2/v3
mount. Its description notes:
This... means that lockd will *not* listen on UDP if the only
mounts are TCP mount (and nfsd hasn't started).
The latter is the only one that concerns me at all - I don't know
if this might be a problem with some servers.
Unfortunately it is a problem for Linux itself. The rpc.statd daemon
on Linux uses UDP for contacting the local lockd, no matter which
protocol is used for NFS mounts. Without a local lockd UDP listener,
NFSv2/v3 lock recovery from Linux NFS clients always fails.
Revert parts of commit 24e36663 so lockd_up() always starts both
listeners.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The nlm_reboot structure is used to store information provided by the
NSM_NOTIFY procedure. This procedure is not specified by the NLM or NSM
protocols, other than to say that the procedure can be used to transmit
information private to a particular NLM/NSM implementation.
For Linux, the callback arguments include the name of the monitored host,
the new NSM state of the host, and a 16-byte private opaque.
As a clean up, remove the unused fields and the server-side XDR logic that
decodes them.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
lockd accepts SM_NOTIFY calls only from a privileged process on the
local system. If lockd uses an AF_INET6 listener, the sender's address
(ie the local rpc.statd) will be the IPv6 loopback address, not the
IPv4 loopback address.
Make sure the privilege test in nlmsvc_proc_sm_notify() and
nlm4svc_proc_sm_notify() works for both AF_INET and AF_INET6 family
addresses by refactoring the test into a helper and adding support for
IPv6 addresses.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Adjust the signature and callers of nlmclnt_grant() to pass a "struct
sockaddr *" instead of a "struct sockaddr_in *" in order to support IPv6
addresses.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Fix up nlmsvc_lookup_host() to pass AF_INET6 source addresses to
nlm_lookup_host().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Pass a struct sockaddr * and a length to nlmclnt_lookup_host() to
accomodate non-AF_INET family addresses.
As a side benefit, eliminate the hostname_len argument, as the hostname
is always NUL-terminated.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Use struct sockaddr * and length in nlm_lookup_host_info to all callers
to pass in either AF_INET or AF_INET6 addresses.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The nlm_lookup_host() function already has a large number of arguments,
and I'm about to add a few more. As a clean up, convert the function
to use a single data structure argument.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The current lockd does not reject reclaims that arrive outside of the
grace period.
Accepting a reclaim means promising to the client that no conflicting
locks were granted since last it held the lock. We can meet that
promise if we assume the only lockers are nfs clients, and that they are
sufficiently well-behaved to reclaim only locks that they held before,
and that only reclaim locks have been permitted so far. Once we leave
the grace period (and start permitting non-reclaims), we can no longer
keep that promise. So we must start rejecting reclaims at that point.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Do all the grace period checks in svclock.c. This simplifies the code a
bit, and will ease some later changes.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Rewrite grace period code to unify management of grace period across
lockd and nfsd. The current code has lockd and nfsd cooperate to
compute a grace period which is satisfactory to them both, and then
individually enforce it. This creates a slight race condition, since
the enforcement is not coordinated. It's also more complicated than
necessary.
Here instead we have lockd and nfsd each inform common code when they
enter the grace period, and when they're ready to leave the grace
period, and allow normal locking only after both of them are ready to
leave.
We also expect the locks_start_grace()/locks_end_grace() interface here
to be simpler to build on for future cluster/high-availability work,
which may require (for example) putting individual filesystems into
grace, or enforcing grace periods across multiple cluster nodes.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: Having two separate functions doesn't add clarity, so
eliminate one of them. Use contemporary kernel coding conventions
where appropriate.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Adopt an approach similar to the RPC server's auth cache (from Aurelien
Charbon and Brian Haley).
Note nlm_lookup_host()'s existing IP address hash function has the same
issue with correctness on little-endian systems as the original IPv4 auth
cache hash function, so I've also updated it with a hash function similar
to the new auth cache hash function.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Update the nlm_cmp_addr() helper to support AF_INET6 as well as AF_INET
addresses. New version takes two "struct sockaddr *" arguments instead of
"struct sockaddr_in *" arguments.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
To store larger addresses in the nsm_handle structure, make sm_addr a
sockaddr_storage.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
To store larger addresses in the nlm_host structure, make h_saddr a
sockaddr_storage. And let's call it something more self-explanatory:
"saddr" could easily be mistaken for "server address".
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
To store larger addresses in the nlm_host structure, make h_addr a
sockaddr_storage, and add an address length field.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Make sure an address family is specified for source addresses passed to
nlm_lookup_host(). nlm_lookup_host() will need this when it becomes
capable of dealing with AF_INET6 addresses.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Knowing which source address is used for communicating with remote NLM
services can be helpful for debugging configuration problems on hosts
with multiple addresses.
Keep the dprintk debugging here, but adapt it so it displays AF_INET6
addresses properly. There are also a couple of dprintk clean-ups as
well.
At some point we will aggregate the helpers that display presentation
format addresses into a single set of shared helpers.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
We're about to introduce some extra debugging messages in nlm_lookup_host().
Bring the coding style up to date first so we can cleanly introduce the new
debugging messages.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
End lockd's grace period using schedule_delayed_work() instead of a
check on every pass through the main loop.
After a later patch, we'll depend on lockd to end its grace period even
if it's not currently handling requests; so it shouldn't depend on being
woken up from the main loop to do so.
Also, Nakano Hiroaki (who independently produced a similar patch)
noticed that the current behavior is buggy in the face of jiffies
wraparound:
"lockd uses time_before() to determine whether the grace period
has expired. This would seem to be enough to avoid timer
wrap-around issues, but, unfortunately, that is not the case.
The time_* family of comparison functions can be safely used to
compare jiffies relatively close in time, but they stop working
after approximately LONG_MAX/2 ticks. nfsd can suffer this
problem because the time_before() comparison in lockd() is not
performed until the first request comes in, which means that if
there is no lockd traffic for more than LONG_MAX/2 ticks we are
screwed.
"The implication of this is that once time_before() starts
misbehaving any attempt from a NFS client to execute fcntl()
will be received with a NLM_LCK_DENIED_GRACE_PERIOD message for
25 days (assuming HZ=1000). In other words, the 50 seconds grace
period could turn into a grace period of 50 days or more.
"Note: This bug was analyzed independently by Oda-san
<oda@valinux.co.jp> and myself."
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Nakano Hiroaki <nakano.hiroaki@oss.ntt.co.jp>
Cc: Itsuro Oda <oda@valinux.co.jp>
The check here is currently harmless but unnecessary, since, as the
comment notes, there aren't any blocked-lock callbacks to process
during the grace period anyway.
And eventually we want to allow multiple grace periods that come and go
for different filesystems over the course of the lifetime of lockd, at
which point this check is just going to get in the way.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Introduce and initialize an address family field in the svc_serv structure.
This field will determine what family to use for the service's listener
sockets and what families are advertised via the local rpcbind daemon.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Use a special error value FILE_LOCK_DEFERRED to mean that a locking
operation returned asynchronously. This is returned by
posix_lock_file() for sleeping locks to mean that the lock has been
queued on the block list, and will be woken up when it might become
available and needs to be retried (either fl_lmops->fl_notify() is
called or fl_wait is woken up).
f_op->lock() to mean either the above, or that the filesystem will
call back with fl_lmops->fl_grant() when the result of the locking
operation is known. The filesystem can do this for sleeping as well
as non-sleeping locks.
This is to make sure, that return values of -EAGAIN and -EINPROGRESS by
filesystems are not mistaken to mean an asynchronous locking.
This also makes error handling in fs/locks.c and lockd/svclock.c slightly
cleaner.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: David Teigland <teigland@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix nlm_fopen() to return NLM_FAILED (or NLM_LCK_DENIED_NOLOCKS) instead
of NLM_LCK_DENIED. The latter means the lock request failed because of a
conflicting lock (i.e. a temporary error), which is wrong in this case.
Also fix the client to return ENOLCK instead of EAGAIN if a blocking lock
request returns with NLM_LOCK_DENIED.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: David Teigland <teigland@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fs/lockd/svcproc.c:115:11: warning: incorrect type in initializer (different base types)
fs/lockd/svcproc.c:115:11: expected int [signed] rc
fs/lockd/svcproc.c:115:11: got restricted __be32 [usertype] <noident>
... and so on...
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* 'for-2.6.27' of git://linux-nfs.org/~bfields/linux: (51 commits)
nfsd: nfs4xdr.c do-while is not a compound statement
nfsd: Use C99 initializers in fs/nfsd/nfs4xdr.c
lockd: Pass "struct sockaddr *" to new failover-by-IP function
lockd: get host reference in nlmsvc_create_block() instead of callers
lockd: minor svclock.c style fixes
lockd: eliminate duplicate nlmsvc_lookup_host call from nlmsvc_lock
lockd: eliminate duplicate nlmsvc_lookup_host call from nlmsvc_testlock
lockd: nlm_release_host() checks for NULL, caller needn't
file lock: reorder struct file_lock to save space on 64 bit builds
nfsd: take file and mnt write in nfs4_upgrade_open
nfsd: document open share bit tracking
nfsd: tabulate nfs4 xdr encoding functions
nfsd: dprint operation names
svcrdma: Change WR context get/put to use the kmem cache
svcrdma: Create a kmem cache for the WR contexts
svcrdma: Add flush_scheduled_work to module exit function
svcrdma: Limit ORD based on client's advertised IRD
svcrdma: Remove unused wait q from svcrdma_xprt structure
svcrdma: Remove unneeded spin locks from __svc_rdma_free
svcrdma: Add dma map count and WARN_ON
...
Push it into those callback functions that actually need it.
Note that all the NFS operations use their own locking, so don't need the
BKL. Ditto for the rpcbind client.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
fcntl(F_GETLK) on an nfs client incorrectly returns
the values for the conflicting lock. fl_len value is
always 1.
If the conflicting lock is (0, 4095) the F_GETLK
request for (1024, 10) returns (0, 1), which doesn't
even cover the requested range, and is quite confusing.
The fix is trivial, set fl_end from the fl_end value
recieved from the nfs server.
Signed-off-by: Felix Blyakher <felixb@sgi.com>
Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Pass a more generic socket address type to nlmsvc_unlock_all_by_ip() to
allow for future support of IPv6. Also provide additional sanity
checking in failover_unlock_ip() when constructing the server's IP
address.
As an added bonus, provide clean kerneldoc comments on related NLM
interfaces which were recently added.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
It may not be obvious (till you look at the definition of
nlm_alloc_call()) that a function like nlmsvc_create_block() should
consume a reference on success or failure, so I find it clearer if it
takes the reference it needs itself.
And both callers already do this immediately before the call anyway.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
nlmsvc_lock calls nlmsvc_lookup_host to find a nlm_host struct. The
callers of this function, however, call nlmsvc_retrieve_args or
nlm4svc_retrieve_args, which also return a nlm_host struct.
Change nlmsvc_lock to take a host arg instead of calling
nlmsvc_lookup_host itself and change the callers to pass a pointer to
the nlm_host they've already found.
Since nlmsvc_testlock() now just uses the caller's reference, we no
longer need to get or release it.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
nlmsvc_testlock calls nlmsvc_lookup_host to find a nlm_host struct. The
callers of this functions, however, call nlmsvc_retrieve_args or
nlm4svc_retrieve_args, which also return a nlm_host struct.
Change nlmsvc_testlock to take a host arg instead of calling
nlmsvc_lookup_host itself and change the callers to pass a pointer to
the nlm_host they've already found.
We take a reference to host in the place where nlmsvc_testlock()
previous did a new lookup, so the reference counting is unchanged from
before.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
If lockd_down is called very rapidly after lockd_up returns, then
there is a slim chance that lockd() will never be called. kthread()
will return before calling the function, so we'll end up never
actually calling the cleanup functions for the thread.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The file_lock structure is used both as a heavy-weight representation of
an active lock, with pointers to reference-counted structures, etc., and
as a simple container for parameters that describe a file lock.
The conflicting lock returned from __posix_lock_file is an example of
the latter; so don't call the filesystem or lock manager callbacks when
copying to it. This also saves the need for an unnecessary
locks_init_lock in the nfsv4 server.
Thanks to Trond for pointing out the error.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Add /proc/fs/nfsd/unlock_filesystem, which allows e.g.:
shell> echo /mnt/sfs1 > /proc/fs/nfsd/unlock_filesystem
so that a filesystem can be unmounted before allowing a peer nfsd to
take over nfs service for the filesystem.
Signed-off-by: S. Wendy Cheng <wcheng@redhat.com>
Cc: Lon Hohberger <lhh@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
fs/lockd/svcsubs.c | 66 +++++++++++++++++++++++++++++++++++++++-----
fs/nfsd/nfsctl.c | 65 +++++++++++++++++++++++++++++++++++++++++++
include/linux/lockd/lockd.h | 7 ++++
3 files changed, 131 insertions(+), 7 deletions(-)
For high-availability NFS service, we generally need to be able to drop
file locks held on the exported filesystem before moving clients to a
new server. Currently the only way to do that is by shutting down lockd
entirely, which is often undesireable (for example, if you want to
continue exporting other filesystems).
This patch allows the administrator to release all locks held by clients
accessing the client through a given server ip address, by echoing that
address to a new file, /proc/fs/nfsd/unlock_ip, as in:
shell> echo 10.1.1.2 > /proc/fs/nfsd/unlock_ip
The expected sequence of events can be:
1. Tear down the IP address
2. Unexport the path
3. Write IP to /proc/fs/nfsd/unlock_ip to unlock files
4. Signal peer to begin take-over.
For now we only support IPv4 addresses and NFSv2/v3 (NFSv4 locks are not
affected).
Also, if unmounting the filesystem is required, we assume at step 3 that
clients using the given server ip are the only clients holding locks on
the given filesystem; otherwise, an additional patch is required to
allow revoking all locks held by lockd on a given filesystem.
Signed-off-by: S. Wendy Cheng <wcheng@redhat.com>
Cc: Lon Hohberger <lhh@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
fs/lockd/svcsubs.c | 66 +++++++++++++++++++++++++++++++++++++++-----
fs/nfsd/nfsctl.c | 65 +++++++++++++++++++++++++++++++++++++++++++
include/linux/lockd/lockd.h | 7 ++++
3 files changed, 131 insertions(+), 7 deletions(-)
* git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (80 commits)
SUNRPC: Invalidate the RPCSEC_GSS session if the server dropped the request
make nfs_automount_list static
NFS: remove duplicate flags assignment from nfs_validate_mount_data
NFS - fix potential NULL pointer dereference v2
SUNRPC: Don't change the RPCSEC_GSS context on a credential that is in use
SUNRPC: Fix a race in gss_refresh_upcall()
SUNRPC: Don't disconnect more than once if retransmitting NFSv4 requests
SUNRPC: Remove the unused export of xprt_force_disconnect
SUNRPC: remove XS_SENDMSG_RETRY
SUNRPC: Protect creds against early garbage collection
NFSv4: Attempt to use machine credentials in SETCLIENTID calls
NFSv4: Reintroduce machine creds
NFSv4: Don't use cred->cr_ops->cr_name in nfs4_proc_setclientid()
nfs: fix printout of multiword bitfields
nfs: return negative error value from nfs{,4}_stat_to_errno
NLM/lockd: Ensure client locking calls use correct credentials
NFS: Remove the buggy lock-if-signalled case from do_setlk()
NLM/lockd: Fix a race when cancelling a blocking lock
NLM/lockd: Ensure that nlmclnt_cancel() returns results of the CANCEL call
NLM: Remove the signal masking in nlmclnt_proc/nlmclnt_cancel
...
When svc_recv returns an unexpected error, lockd will print a warning
and exit. This problematic for several reasons. In particular, it will
cause the reference counts for the thread to be wrong, and can lead to a
potential BUG() call.
Rather than exiting on error from svc_recv, have the thread do a 1s
sleep and then retry the loop. This is unlikely to cause any harm, and
if the error turns out to be something temporary then it may be able to
recover.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
As of 5996a298da ("NLM: don't unlock on
cancel requests") we no longer unlock in this case, so the comment is no
longer accurate.
Thanks to Stuart Friedberg for pointing out the inconsistency.
Cc: Stuart Friedberg <sfriedberg@hp.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
There's no reason for a mutex here, except to allow an allocation under
the lock, which we can avoid with the usual trick of preallocating
memory for the new object and freeing it if it turns out to be
unnecessary.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Use list_for_each_entry(). Also, in keeping with kernel style, make the
normal case (kzalloc succeeds) unindented and handle the abnormal case
with a goto.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
The sm_count is decremented to zero but left on the nsm_handles list.
So in the space between decrementing sm_count and acquiring nsm_mutex,
it is possible for another task to find this nsm_handle, increment the
use count and then enter nsm_release itself.
Thus there's nothing to prevent the nsm being freed before we acquire
nsm_mutex here.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
fs/lockd/svcshare.c:74:50: warning: Using plain integer as NULL pointer
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Have lockd_up start lockd using kthread_run. With this change,
lockd_down now blocks until lockd actually exits, so there's no longer
need for the waitqueue code at the end of lockd_down. This also means
that only one lockd can be running at a time which simplifies the code
within lockd's main loop.
This also adds a check for kthread_should_stop in the main loop of
nlmsvc_retry_blocked and after that function returns. There's no sense
continuing to retry blocks if lockd is coming down anyway.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Lockd caches information about hosts that have recently held locks to
expedite the taking of further locks.
It periodically discards this information for hosts that have not been
used for a few minutes.
lockd currently has a value NLM_HOST_MAX, and changes the 'garbage
collection' behaviour when the number of hosts exceeds this threshold.
However its behaviour is strange, and likely not what was intended.
When the number of hosts exceeds the max, it scans *less* often (every
2 minutes vs every minute) and allows unused host information to
remain around longer (5 minutes instead of 2).
Having this limit is of dubious value anyway, and we have not
suffered from the code not getting the limit right, so remove the
limit altogether. We go with the larger values (discard 5 minute old
hosts every 2 minutes) as they are probably safer.
Maybe the periodic garbage collection should be replace to with
'shrinker' handler so we just respond to memory pressure....
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Now that we've added the 'generic' credentials (that are independent of the
rpc_client) to the nfs_open_context, we can use those in the NLM client to
ensure that the lock/unlock requests are authenticated to whoever
originally opened the file.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We shouldn't remove the lock from the list of blocked locks until the
CANCEL call has completed since we may be racing with a GRANTED callback.
Also ensure that we send an UNLOCK if the CANCEL request failed. Normally
that should only happen if the process gets hit with a fatal signal.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, it returns success as long as the RPC call was sent. We'd like
to know if the CANCEL operation succeeded on the server.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Peter Staubach comments:
> In the course of investigating testing failures in the locking phase of
> the Connectathon testsuite, I discovered a couple of things. One was
> that one of the tests in the locking tests was racy when it didn't seem
> to need to be and two, that the NFS client asynchronously releases locks
> when a process is exiting.
...
> The Single UNIX Specification Version 3 specifies that: "All locks
> associated with a file for a given process shall be removed when a file
> descriptor for that file is closed by that process or the process holding
> that file descriptor terminates.".
>
> This does not specify whether those locks must be released prior to the
> completion of the exit processing for the process or not. However,
> general assumptions seem to be that those locks will be released. This
> leads to more deterministic behavior under normal circumstances.
The following patch converts the NFSv2/v3 locking code to use the same
mechanism as NFSv4 for sending asynchronous RPC calls and then waiting for
them to complete. This ensures that the UNLOCK and CANCEL RPC calls will
complete even if the user interrupts the call, yet satisfies the
above request for synchronous behaviour on process exit.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When we replace the existing synchronous RPC calls with asynchronous calls,
the reference count will be needed in order to allow us to examine the
result of the RPC call.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Also fix up nlmclnt_lock() so that it doesn't pass modified versions of
fl->fl_flags to nlmclnt_cancel() and other helpers.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: refactor the encoding of the opaque 16-byte private argument in
xdr_encode_mon(). This will be updated later to support IPv6 addresses.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Switch to using the new mon_id encoder function.
Now that we've refactored the encoding of SM_MON requests, we've
discovered that the pre-computed buffer length maximums are
incorrect!
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: document the argument type that xdr_encode_common() is
marshalling by introducing a new function. The new function will replace
xdr_encode_common() in just a sec.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: introduce a new XDR encoder specifically for the my_id
argument of SM_MON requests.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: introduce a new XDR encoder specifically for the mon_name
argument of SM_MON requests. This will be updated later to support IPv6
addresses in addition to IPv4 addresses.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Introduce a special helper function to check the length of NSM strings
before they are placed on the wire.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: RPC protocol version numbers are u32. Make sure we use an
appropriate type for NLM version numbers when calling nlm_lookup_host().
Eliminates a harmless mixed sign comparison in nlm_host_lookup().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Bruce Fields says:
"By the way, we've got another config-related nit here:
http://bugzilla.linux-nfs.org/show_bug.cgi?id=156
You can build lockd without CONFIG_SYSCTL set, but then the module will
fail to load."
For now, disable the sysctl registration calls in lockd if CONFIG_SYSCTL
is not enabled. This allows the kernel to build properly if PROC_FS or
SYSCTL is not enabled, but an NFS client is desired.
In the long run, we would like to be able to build the kernel with an
NFS client but without lockd. This makes sense, for example, if you want
an NFSv4-only NFS client, as NFSv4 doesn't use NLM at all.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Sorry for the noise, but here's the v3 of this compilation fix :)
There are some places, which declare the char buf[...] on the stack
to push it later into dprintk(). Since the dprintk sometimes (if the
CONFIG_SYSCTL=n) becomes an empty do { } while (0) stub, these buffers
cause gcc to produce appropriate warnings.
Wrap these buffers with RPC_IFDEBUG macro, as Trond proposed, to
compile them out when not needed.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It's possible for lockd to catch a SIGKILL while a GRANT_MSG callback
is in flight. If this happens we don't want lockd to insert the block
back into the nlm_blocked list.
This helps that situation, but there's still a possible race. Fixing
that will mean adding real locking for nlm_blocked.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
With the current scheme in nlmsvc_grant_blocked, we can end up with more
than one GRANT_MSG callback for a block in flight. Right now, we requeue
the block unconditionally so that a GRANT_MSG callback is done again in
30s. If the client is unresponsive, it can take more than 30s for the
call already in flight to time out.
There's no benefit to having more than one GRANT_MSG RPC queued up at a
time, so put it on the list with a timeout of NLM_NEVER before doing the
RPC call. If the RPC call submission fails, we requeue it with a short
timeout. If it works, then nlmsvc_grant_callback will end up requeueing
it with a shorter timeout after it completes.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Now that it no longer does an RPC ping, lockd always ends up queueing
an RPC task for the GRANT_MSG callback. But, it also requeues the block
for later attempts. Since these are hard RPC tasks, if the client we're
calling back goes unresponsive the GRANT_MSG callbacks can stack up in
the RPC queue.
Fix this by making server-side RPC clients default to soft RPC tasks.
lockd requeues the block anyway, so this should be OK.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
It's currently possible for an unresponsive NLM client to completely
lock up a server's lockd. The scenario is something like this:
1) client1 (or a process on the server) takes a lock on a file
2) client2 tries to take a blocking lock on the same file and
awaits the callback
3) client2 goes unresponsive (plug pulled, network partition, etc)
4) client1 releases the lock
...at that point the server's lockd will try to queue up a GRANT_MSG
callback for client2, but first it requeues the block with a timeout of
30s. nlm_async_call will attempt to bind the RPC client to client2 and
will call rpc_ping. rpc_ping entails a sync RPC call and if client2 is
unresponsive it will take around 60s for that to time out. Once it times
out, it's already time to retry the block and the whole process repeats.
Once in this situation, nlmsvc_retry_blocked will never return until
the host starts responding again. lockd won't service new calls.
Fix this by skipping the RPC ping on NLM RPC clients. This makes
nlm_async_call return quickly when called.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
It's possible for a RPC to outlive the lockd daemon that created it, so
we need to make sure that all RPC's are killed when lockd is coming
down. When nlm_shutdown_hosts is called, kill off all RPC tasks
associated with the host. Since we need to wait until they have all gone
away, we might as well just shut down the RPC client altogether.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Update the write handler for the portlist file to allow creating new
listening endpoints on a transport. The general form of the string is:
<transport_name><space><port number>
For example:
echo "tcp 2049" > /proc/fs/nfsd/portlist
This is intended to support the creation of a listening endpoint for
RDMA transports without adding #ifdef code to the nfssvc.c file.
Transports can also be removed as follows:
'-'<transport_name><space><port number>
For example:
echo "-tcp 2049" > /proc/fs/nfsd/portlist
Attempting to add a listener with an invalid transport string results
in EPROTONOSUPPORT and a perror string of "Protocol not supported".
Attempting to remove an non-existent listener (.e.g. bad proto or port)
results in ENOTCONN and a perror string of
"Transport endpoint is not connected"
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Neil Brown <neilb@suse.de>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Greg Banks <gnb@sgi.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Add a new svc function that allows a service to query whether a
transport instance has already been created. This is used in lockd
to determine whether or not a transport needs to be created when
a lockd instance is brought up.
Specifying 0 for the address family or port is effectively a wild-card,
and will result in matching the first transport in the service's list
that has a matching class name.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Neil Brown <neilb@suse.de>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Greg Banks <gnb@sgi.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Move sk_list and sk_ready to svc_xprt. This involves close because these
lists are walked by svcs when closing all their transports. So I combined
the moving of these lists to svc_xprt with making close transport independent.
The svc_force_sock_close has been changed to svc_close_all and takes a list
as an argument. This removes some svc internals knowledge from the svcs.
This code races with module removal and transport addition.
Thanks to Simon Holm Thøgersen for a compile fix.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Neil Brown <neilb@suse.de>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Greg Banks <gnb@sgi.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Simon Holm Thøgersen <odie@cs.aau.dk>
Modify the various kernel RPC svcs to use the svc_create_xprt service.
Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Neil Brown <neilb@suse.de>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Greg Banks <gnb@sgi.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Fix nlm_block leak for the case of supplied blocking lock info.
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Without the patch, there is a leakage of nlmblock structure refcount
that holds a reference nlmfile structure, that holds a reference to
struct file, when async GETFL is used (-EINPROGRESS return from
file_ops->lock()), and also in some error cases.
Fix up a style nit while we're here.
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
In a number of places where we wish only to translate nlm_drop_reply to
rpc_drop_reply errors we instead return early with rpc_drop_reply,
skipping some important end-of-function cleanup.
This results in reference count leaks when lockd is doing posix locking
on GFS2.
Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
According to The Open Group's NLM specification, NLM callers are variable
length strings. XDR variable length strings use an unsigned 32 bit length.
And internally, negative string lengths are not meaningful for the Linux
NLM implementation.
Clean up: Make nlm_lock.len and nlm_reboot.len unsigned integers. This
makes the sign of NLM string lengths consistent with the sign of xdr_netobj
lengths.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-By: NeilBrown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Clean up: pass 5 arguments to nlmclnt_init() in a structure similar to the
new nfs_client_initdata structure.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Now that each NFS mount point caches its own nlm_host structure, it can be
passed to nlmclnt_proc() for each lock request. By pinning an nlm_host for
each mount point, we trade the overhead of looking up or creating a fresh
nlm_host struct during every NLM procedure call for a little extra memory.
We also restrict the nlmclnt_proc symbol to limit the use of this call to
in-tree modules.
Note that nlm_lookup_host() (just removed from the client's per-request
NLM processing) could also trigger an nlm_host garbage collection. Now
client-side nlm_host garbage collection occurs only during NFS mount
processing. Since the NFS client now holds a reference on these nlm_host
structures, they wouldn't have been affected by garbage collection
anyway.
Given that nlm_lookup_host() reorders the global nlm_host chain after
every successful lookup, and that a garbage collection could be triggered
during the call, we've removed a significant amount of per-NLM-request
CPU processing overhead.
Sidebar: there are only a few remaining references to the internals of
NFS inodes in the client-side NLM code. The only references I found are
related to extracting or comparing the inode's file handle via NFS_FH().
One is in nlmclnt_grant(); the other is in nlmclnt_setlockargs().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We would like to remove the per-lock-operation nlm_lookup_host() call from
nlmclnt_proc().
The new architecture pins an nlm_host structure to each NFS client
superblock that has the "lock" mount option set. The NFS client passes
in the pinned nlm_host structure during each call to nlmclnt_proc(). NFS
client unmount processing "puts" the nlm_host so it can be garbage-
collected later.
This patch introduces externally callable NLM functions that handle
mount-time nlm_host set up and tear-down.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The cookie->len field is unsigned, so the loop index variable in
nlmdbg_cookie2a() should also be unsigned.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Instead of an { address family, raw IP protocol number }-tuple, use the
newly-defined RPC identifier when creating clients in the upper layers.
Signed-off-by: Tom Talpey <tmt@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Due to recent edict to remove or replace printk's that might flood the
system log.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The recent fix for a circular lock dependency unfortunately introduced a
potential memory leak in the event where the call to nlmsvc_lookup_host
fails for some reason.
Thanks to Roel Kluin for spotting this.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The problem is that the garbage collector for the 'host' structures
nlm_gc_hosts(), holds nlm_host_mutex while calling down to
nlmsvc_mark_resources, which, eventually takes the file->f_mutex.
We cannot therefore call nlmsvc_lookup_host() from within
nlmsvc_create_block, since the caller will already hold file->f_mutex, so
the attempt to grab nlm_host_mutex may deadlock.
Fix the problem by calling nlmsvc_lookup_host() outside the file->f_mutex.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Both lockd and (in the nfsv4 case) nfsd enforce a "grace period" after reboot,
during which clients may reclaim locks from the previous server instance, but
may not acquire new locks.
Currently the lockd and nfsd enforce grace periods of different lengths. This
may cause problems when we reboot a server with both v2/v3 and v4 clients.
For example, if the lockd grace period is shorter (as is likely the case),
then a v3 client might acquire a new lock that conflicts with a lock already
held (but not yet reclaimed) by a v4 client.
This patch calculates a lease time that lockd and nfsd can both use.
Signed-off-by: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, the freezer treats all tasks as freezable, except for the kernel
threads that explicitly set the PF_NOFREEZE flag for themselves. This
approach is problematic, since it requires every kernel thread to either
set PF_NOFREEZE explicitly, or call try_to_freeze(), even if it doesn't
care for the freezing of tasks at all.
It seems better to only require the kernel threads that want to or need to
be frozen to use some freezer-related code and to remove any
freezer-related code from the other (nonfreezable) kernel threads, which is
done in this patch.
The patch causes all kernel threads to be nonfreezable by default (ie. to
have PF_NOFREEZE set by default) and introduces the set_freezable()
function that should be called by the freezable kernel threads in order to
unset PF_NOFREEZE. It also makes all of the currently freezable kernel
threads call set_freezable(), so it shouldn't cause any (intentional)
change of behaviour to appear. Additionally, it updates documentation to
describe the freezing of tasks more accurately.
[akpm@linux-foundation.org: build fixes]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Nigel Cunningham <nigel@nigel.suspend2.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use the destination address of the original NLM request as the
source address in callbacks to the client.
Signed-off-by: Frank van Maarseveen <frankvm@frankvm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Replace it with explicit calls to rpc_shutdown_client() or
rpc_destroy_client() (for the case of asynchronous calls).
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Harvey Harrison