Commit Graph

322 Commits

Author SHA1 Message Date
Chuck Lever
8c7378fd2a NLM: Call nsm_reboot_lookup() instead of nsm_find()
Invoke the newly introduced nsm_reboot_lookup() function in
nlm_host_rebooted() instead of nsm_find().

This introduces just one behavioral change: debugging messages
produced during reboot notification will now appear when the
NLMDBG_MONITOR flag is set, but not when the NLMDBG_HOSTCACHE flag
is set.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:54 -05:00
Chuck Lever
3420a8c435 NSM: Add nsm_lookup() function
Introduce a new API to fs/lockd/mon.c that allows nlm_host_rebooted()
to lookup up nsm_handles via the contents of an nlm_reboot struct.

The new function is equivalent to calling nsm_find() with @create set
to zero, but it takes a struct nlm_reboot instead of separate
arguments.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:54 -05:00
Chuck Lever
576df4634e NLM: Decode "priv" argument of NLMPROC_SM_NOTIFY as an opaque
The NLM XDR decoders for the NLMPROC_SM_NOTIFY procedure should treat
their "priv" argument truly as an opaque, as defined by the protocol,
and let the upper layers figure out what is in it.

This will make it easier to modify the contents and interpretation of
the "priv" argument, and keep knowledge about what's in "priv" local
to fs/lockd/mon.c.

For now, the NLM and NSM implementations should behave exactly as they
did before.

The formation of the address of the rebooted host in
nlm_host_rebooted() may look a little strange, but it is the inverse
of how nsm_init_private() forms the private cookie.  Plus, it's
going away soon anyway.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:54 -05:00
Chuck Lever
7fefc9cb9d NLM: Change nlm_host_rebooted() to take a single nlm_reboot argument
Pass the nlm_reboot data structure directly from the NLMPROC_SM_NOTIFY
XDR decoders to nlm_host_rebooted().  This eliminates some packing and
unpacking of the NLMPROC_SM_NOTIFY results, and prepares for passing
these results, including the "priv" cookie, directly to a lookup
routine in fs/lockd/mon.c.

This patch changes code organization but should not cause any
behavioral change.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:54 -05:00
Chuck Lever
cab2d3c991 NSM: Encode the new "priv" cookie for NSMPROC_MON requests
Pass the new "priv" cookie to NSMPROC_MON's XDR encoder, instead of
creating the "priv" argument in the encoder at call time.

This patch should not cause a behavioral change: the contents of the
cookie remain the same for the time being.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:54 -05:00
Chuck Lever
7e44d3bea2 NSM: Generate NSMPROC_MON's "priv" argument when nsm_handle is created
Introduce a new data type, used by both the in-kernel NLM and NSM
implementations, that is used to manage the opaque "priv" argument
for the NSMPROC_MON and NLMPROC_SM_NOTIFY calls.

Construct the "priv" cookie when the nsm_handle is created.

The nsm_init_private() function may look a little strange, but it is
roughly equivalent to how the XDR encoder formed the "priv" argument.
It's going to go away soon.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:53 -05:00
Chuck Lever
05f3a9af58 NSM: Remove !nsm check from nsm_release()
The nsm_release() function should never be called with a NULL handle
point.  If it is, that's a bug.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:53 -05:00
Chuck Lever
bc1cc6c4e4 NSM: Remove NULL pointer check from nsm_find()
The nsm_find() function should never be called with a NULL IP address
pointer.  If it is, that's a bug.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:53 -05:00
Chuck Lever
5cf1c4b19d NSM: Add dprintk() calls in nsm_find and nsm_release
Introduce some dprintk() calls in fs/lockd/mon.c that are enabled by
the NLMDBG_MONITOR flag.  These report when we find, create, and
release nsm_handles.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:53 -05:00
Chuck Lever
67c6d107a6 NSM: Move nsm_find() to fs/lockd/mon.c
The nsm_find() function sets up fresh nsm_handle entries.  This is
where we will store the "priv" cookie used to lookup nsm_handles during
reboot recovery.  The cookie will be constructed when nsm_find()
creates a new nsm_handle.

As much as possible, I would like to keep everything that handles a
"priv" cookie in fs/lockd/mon.c so that all the smarts are in one
source file.  That organization should make it pretty simple to see how
all this works.

To me, it makes more sense than the current arrangement to keep
nsm_find() with nsm_monitor() and nsm_unmonitor().

So, start reorganizing by moving nsm_find() into fs/lockd/mon.c.  The
nsm_release() function comes along too, since it shares the nsm_lock
global variable.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:53 -05:00
Chuck Lever
03eb1dcbb7 NSM: move to xdr_stream-based XDR encoders and decoders
Introduce xdr_stream-based XDR encoder and decoder functions, which are
more careful about preventing RPC buffer overflows.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:53 -05:00
Chuck Lever
36e8e668d3 NSM: Move NSM program and procedure numbers to fs/lockd/mon.c
Clean up: Move the RPC program and procedure numbers for NSM into the
one source file that needs them: fs/lockd/mon.c.

And, as with NLM, NFS, and rpcbind calls, use NSMPROC_FOO instead of
SM_FOO for NSM procedure numbers.

Finally, make a couple of comments more precise: what is referred to
here as SM_NOTIFY is really the NLM (lockd) NLMPROC_SM_NOTIFY downcall,
not NSMPROC_NOTIFY.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:52 -05:00
Chuck Lever
9c1bfd037f NSM: Move NSM-related XDR data structures to lockd's xdr.h
Clean up: NSM's XDR data structures are used only in fs/lockd/mon.c,
so move them there.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:52 -05:00
Chuck Lever
0c7aef4569 NSM: Check result of SM_UNMON upcall
Make sure any error returned by rpc.statd during an SM_UNMON call is
reported rather than ignored completely.  There isn't much to do with
such an error, but we should log it in any case.

Similar to a recent change to nsm_monitor().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:52 -05:00
Chuck Lever
356c3eb466 NLM: Move the public declaration of nsm_unmonitor() to lockd.h
Clean up.

Make the nlm_host argument "const," and move the public declaration to
lockd.h.  Add a documenting comment.

Bruce observed that nsm_unmonitor()'s only caller doesn't care about
its return code, so make nsm_unmonitor() return void.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:52 -05:00
Chuck Lever
c8c23c423d NSM: Release nsmhandle in nlm_destroy_host
The nsm_handle's reference count is bumped in nlm_lookup_host().  It
should be decremented in nlm_destroy_host() to make it easier to see
the balance of these two operations.

Move the nsm_release() call to fs/lockd/host.c.

The h_nsmhandle pointer is set in nlm_lookup_host(), and never cleared.
The nlm_destroy_host() function is never called for the same nlm_host
twice, so h_nsmhandle won't ever be NULL when nsm_unmonitor() is
called.

All references to the nlm_host are gone before it is freed.  We can
skip making h_nsmhandle NULL just before the nlm_host is deallocated.

It's also likely we can remove the h_nsmhandle NULL check in
nlmsvc_is_client() as well, but we can do that later when rearchitect-
ing the nlm_host cache.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:52 -05:00
Chuck Lever
1e49323c4a NLM: Move the public declaration of nsm_monitor() to lockd.h
Clean up.

Make the nlm_host argument "const," and move the public declaration to
lockd.h with other NSM public function (nsm_release, eg) and global
variable declarations.

Add a documenting comment.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:52 -05:00
Chuck Lever
5d254b1198 NSM: Make sure to return an error if the SM_MON call result is not zero
The nsm_monitor() function reports an error and does not set sm_monitored
if the SM_MON upcall reply has a non-zero result code, but nsm_monitor()
does not return an error to its caller in this case.

Since sm_monitored is not set, the upcall is retried when the next NLM
request invokes nsm_monitor().  However, that may not come for a while.
In the meantime, at least one NLM request will potentially proceed
without the peer being monitored properly.

Have nsm_monitor() return an error if the result code is non-zero.
This will cause all NLM requests to fail immediately if the upcall
completed successfully but rpc.statd returned an error.

This may be inconvenient in some cases (for example if rpc.statd
cannot complete a proper DNS reverse lookup of the hostname), but will
make the reboot monitoring service more robust by forcing such issues
to be corrected by an admin.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:51 -05:00
Chuck Lever
5bc74bef7c NSM: Remove BUG_ON() in nsm_monitor()
Clean up: Remove the BUG_ON() invocation in nsm_monitor().  It's not
likely that nsm_monitor() is ever called with a NULL host pointer, and
the code will die anyway if host is NULL.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:51 -05:00
Chuck Lever
501c1ed3fb NLM: Remove redundant printk() in nlmclnt_lock()
The nsm_monitor() function already generates a printk(KERN_NOTICE) if
the SM_MON upcall fails, so the similar printk() in the nlmclnt_lock()
function is redundant.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:51 -05:00
Chuck Lever
9fee49024e NSM: Use sm_name instead of h_name in nsm_monitor() and nsm_unmonitor()
Clean up: Use the sm_name field for reporting the hostname in nsm_monitor()
and nsm_unmonitor(), just as the other functions in fs/lockd/mon.c do.

The h_name field is just a copy of the sm_name pointer.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:51 -05:00
Chuck Lever
29ed1407ed NSM: Support IPv6 version of mon_name
The "mon_name" argument of the NSMPROC_MON and NSMPROC_UNMON upcalls
is a string that contains the hostname or IP address of the remote peer
to be notified when this host has rebooted.  The sm-notify command uses
this identifier to contact the peer when we reboot, so it must be
either a well-qualified DNS hostname or a presentation format IP
address string.

When the "nsm_use_hostnames" sysctl is set to zero, the kernel's NSM
provides a presentation format IP address in the "mon_name" argument.
Otherwise, the "caller_name" argument from NLM requests is used,
which is usually just the DNS hostname of the peer.

To support IPv6 addresses for the mon_name argument, we use the
nsm_handle's address eye-catcher, which already contains an appropriate
presentation format address string.  Using the eye-catcher string
obviates the need to use a large buffer on the stack to form the
presentation address string for the upcall.

This patch also addresses a subtle bug.

An NSMPROC_MON request and the subsequent NSMPROC_UNMON request for the
same peer are required to use the same value for the "mon_name"
argument.  Otherwise, rpc.statd's NSMPROC_UNMON processing cannot
locate the database entry for that peer and remove it.

If the setting of nsm_use_hostnames is changed between the time the
kernel sends an NSMPROC_MON request and the time it sends the
NSMPROC_UNMON request for the same peer, the "mon_name" argument for
these two requests may not be the same.  This is because the value of
"mon_name" is currently chosen at the moment the call is made based on
the setting of nsm_use_hostnames

To ensure both requests pass identical contents in the "mon_name"
argument, we now select which string to use for the argument in the
nsm_monitor() function.  A pointer to this string is saved in the
nsm_handle so it can be used for a subsequent NSMPROC_UNMON upcall.

NB: There are other potential problems, such as how nlm_host_rebooted()
might behave if nsm_use_hostnames were changed while hosts are still
being monitored.  This patch does not attempt to address those
problems.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:51 -05:00
Chuck Lever
5acf43155d NSM: convert printk(KERN_DEBUG) to a dprintk()
Clean up: make the printk(KERN_DEBUG) in nsm_mon_unmon() a dprintk,
and add another dprintk to note if creating an RPC client for the
upcall failed.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:50 -05:00
Chuck Lever
a4846750f0 NSM: Use C99 structure initializer to initialize nsm_args
Clean up: Use a C99 structure initializer instead of open-coding the
initialization of nsm_args.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:50 -05:00
Chuck Lever
afb03699dc NLM: Add helper to handle IPv4 addresses
Clean up: introduce a helper function to generate IPv4 addresses using
the same style as the IPv6 helper function we just added.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:49 -05:00
Chuck Lever
bc995801a0 NLM: Support IPv6 scope IDs in nlm_display_address()
Scope ID support is needed since the kernel's NSM implementation is
about to use these displayed addresses as a mon_name in some cases.

When nsm_use_hostnames is zero, without scope ID support NSM will fail
to handle peers that contact us via a link-local address.  Link-local
addresses do not work without an interface ID, which is stored in the
sockaddr's sin6_scope_id field.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:49 -05:00
Chuck Lever
6999fb4016 NLM: Remove AF_UNSPEC arm in nlm_display_address()
AF_UNSPEC support is no longer needed in nlm_display_address() now
that a presentation address is no longer generated for the h_srcaddr
field.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:49 -05:00
Chuck Lever
1df40b609a NLM: Remove address eye-catcher buffers from nlm_host
The h_name field in struct nlm_host is a just copy of
h_nsmhandle->sm_name.  Likewise, the contents of the h_addrbuf field
should be identical to the sm_addrbuf field.

The h_srcaddrbuf field is used only in one place for debugging.  We can
live without this until we get %pI formatting for printk().

Currently these buffers are 48 bytes, but we need to support scope IDs
in IPv6 presentation addresses, which means making the buffers even
larger.  Instead, let's find ways to eliminate them to save space.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:49 -05:00
Jeff Layton
c72a476b4b lockd: set svc_serv->sv_maxconn to a more reasonable value (try #3)
The default method for calculating the number of connections allowed
per RPC service arbitrarily limits single-threaded services to 80
connections. This is too low for services like lockd and artificially
limits the number of TCP clients that it can support.

Have lockd set a default sv_maxconn value to 1024 (which is the typical
default value for RLIMIT_NOFILE. Also add a module parameter to allow an
admin to set this to an arbitrary value.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Neil Brown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:48 -05:00
Trond Myklebust
08cc36cbd1 Merge branch 'devel' into next 2008-12-30 16:51:43 -05:00
Chuck Lever
0cb2659b81 NLM: allow lockd requests from an unprivileged port
If the admin has specified the "noresvport" option for an NFS mount
point, the kernel's NFS client uses an unprivileged source port for
the main NFS transport.  The kernel's lockd client should use an
unprivileged port in this case as well.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-12-23 15:21:38 -05:00
Jeff Layton
df94f000c4 lockd: convert reclaimer thread to kthread interface
My understanding is that there is a push to turn the kernel_thread
interface into a non-exported symbol and move all kernel threads to use
the kthread API. This patch changes lockd to use kthread_run to spawn
the reclaimer thread.

I've made the assumption here that the extra module references taken
when we spawn this thread are unnecessary and removed them. I've also
added a KERN_ERR printk that pops if the thread can't be spawned to warn
the admin that the locks won't be reclaimed.

In the future, it would be nice to be able to notify userspace that
locks have been lost (probably by implementing SIGLOST), and adding some
good policies about how long we should reattempt to reclaim the locks.

Finally, I removed a comment about memory leaks that I believe is
obsolete and added a new one to clarify the result of sending a SIGKILL
to the reclaimer thread. As best I can tell, doing so doesn't actually
cause a memory leak.

I consider this patch 2.6.29 material.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-12-23 15:21:33 -05:00
Trond Myklebust
2de59872a7 LOCKD: Make lockd_up() and lockd_down() exported GPL-only
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-12-23 15:21:33 -05:00
David S. Miller
eb14f01959 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:

	drivers/net/e1000e/ich8lan.c
2008-12-15 20:03:50 -08:00
Chuck Lever
a8d82d9b95 NLM: client-side nlm_lookup_host() should avoid matching on srcaddr
Since commit c98451bd, the loop in nlm_lookup_host() unconditionally
compares the host's h_srcaddr field to the incoming source address.
For client-side nlm_host entries, both are always AF_UNSPEC, so this
check is unnecessary.

Since commit 781b61a6, which added support for AF_INET6 addresses to
nlm_cmp_addr(), nlm_cmp_addr() now returns FALSE for AF_UNSPEC
addresses, which causes nlm_lookup_host() to create a fresh nlm_host
entry every time it is called on the client.

These extra entries will eventually expire once the server is
unmounted, so the impact of this regression, introduced with lockd
IPv6 support in 2.6.28, should be minor.

We could fix this by adding an arm in nlm_cmp_addr() for AF_UNSPEC
addresses, but really, nlm_lookup_host() shouldn't be matching on the
srcaddr field for client-side nlm_host lookups.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-11-24 13:29:07 -06:00
J. Bruce Fields
2c5e76158f nfsd: clean up grace period on early exit
If nfsd was shut down before the grace period ended, we could end up
with a freed object still on grace_list.  Thanks to Jeff Moyer for
reporting the resulting list corruption warnings.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Tested-by: Jeff Moyer <jmoyer@redhat.com>
2008-11-24 10:12:48 -06:00
David S. Miller
9eeda9abd1 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:

	drivers/net/wireless/ath5k/base.c
	net/8021q/vlan_core.c
2008-11-06 22:43:03 -08:00
Harvey Harrison
be85940548 fs: replace NIPQUAD()
Using NIPQUAD() with NIPQUAD_FMT, %d.%d.%d.%d or %u.%u.%u.%u
can be replaced with %pI4

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-31 00:56:28 -07:00
Chuck Lever
d7dc61d0a7 NLM: Set address family before calling nlm_host_rebooted()
The nlm_host_rebooted() function uses nlm_cmp_addr() to find an
nsm_handle that matches the rebooted peer.  In order for this to work,
the passed-in address must have a proper address family.

This fixes a post-2.6.28 regression introduced by commit 781b61a6, which
added AF_INET6 support to nlm_cmp_addr().  Before that commit,
nlm_cmp_addr() didn't care about the address family; it compared only
the sin_addr.s_addr field for equality.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-10-30 17:19:30 -04:00
Harvey Harrison
5b095d9892 net: replace %p6 with %pI6
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-29 12:52:50 -07:00
Harvey Harrison
1afa67f5e7 misc: replace NIP6_FMT with %p6 format specifier
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>
2008-10-28 16:06:44 -07:00
Chuck Lever
26a4140923 NLM: Remove "proto" argument from lockd_up()
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>
2008-10-04 17:12:27 -04:00
Chuck Lever
8c3916f4bd NLM: Always start both UDP and TCP listeners
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>
2008-10-04 17:08:16 -04:00
Chuck Lever
9a38a83880 lockd: Remove unused fields in the nlm_reboot structure
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>
2008-10-03 17:02:35 -04:00
Chuck Lever
b85e467634 lockd: Add helper to sanity check incoming NOTIFY requests
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>
2008-10-03 17:02:35 -04:00
Chuck Lever
dcff09f124 lockd: change nlmclnt_grant() to take a "struct sockaddr *"
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>
2008-10-03 17:02:35 -04:00
Chuck Lever
6bfbe8af46 lockd: Adjust nlmsvc_lookup_host() to accomodate AF_INET6 addresses
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>
2008-10-03 17:02:35 -04:00
Chuck Lever
d7d204403b lockd: Adjust nlmclnt_lookup_host() signature to accomodate non-AF_INET
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>
2008-10-03 17:02:34 -04:00
Chuck Lever
88541c8487 lockd: Support non-AF_INET addresses in nlm_lookup_host()
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>
2008-10-03 17:01:57 -04:00
Chuck Lever
7f1ed18bd3 NLM: Convert nlm_lookup_host() to use a single argument
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>
2008-10-03 16:58:23 -04:00
J. Bruce Fields
d22b1cff09 lockd: reject reclaims outside the grace period
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>
2008-10-03 16:19:20 -04:00
J. Bruce Fields
b2b5028905 lockd: move grace period checks to common code
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>
2008-10-03 16:19:19 -04:00
J. Bruce Fields
af558e33be nfsd: common grace period control
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>
2008-10-03 16:19:02 -04:00
Chuck Lever
e018040a82 lockd: Update nsm_find() to support non-AF_INET addresses
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29 18:13:39 -04:00
Chuck Lever
bc48e4d637 lockd: Combine __nsm_find() and nsm_find().
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>
2008-09-29 18:13:39 -04:00
Chuck Lever
ede2fea099 lockd: Support AF_INET6 when hashing addresses in nlm_lookup_host
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>
2008-09-29 18:13:39 -04:00
Chuck Lever
781b61a6f4 lockd: Teach nlm_cmp_addr() to support AF_INET6 addresses
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>
2008-09-29 18:13:39 -04:00
Chuck Lever
7e9d7746bf NSM: Use sockaddr_storage for sm_addr field
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>
2008-09-29 18:13:39 -04:00
Chuck Lever
90151e6e4d lockd: Use sockaddr_storage for h_saddr field
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>
2008-09-29 18:13:39 -04:00
Chuck Lever
b4ed58fd34 lockd: Use sockaddr_storage + length for h_addr field
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>
2008-09-29 18:13:39 -04:00
Chuck Lever
396cb3d003 lockd: Add address family-agnostic helper for zeroing the port number
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29 18:13:38 -04:00
Chuck Lever
2860a0227b lockd: Specify address family for source address
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>
2008-09-29 18:13:38 -04:00
Chuck Lever
1b333c54a1 lockd: address-family independent printable addresses
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>
2008-09-29 18:13:38 -04:00
Chuck Lever
c2526f4271 NLM: Clean up before introducing new debugging messages
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>
2008-09-29 18:13:38 -04:00
J. Bruce Fields
c8ab5f2a13 lockd: don't depend on lockd main loop to end grace
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>
2008-09-29 18:13:10 -04:00
J. Bruce Fields
8fafa90082 locks: allow lockd to process blocked locks during grace period
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>
2008-09-29 17:56:59 -04:00
Chuck Lever
e851db5b05 SUNRPC: Add address family field to svc_serv data structure
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>
2008-09-29 17:56:56 -04:00
Linus Torvalds
b0e0c9e7f6 Merge branch 'for-2.6.27' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.27' of git://linux-nfs.org/~bfields/linux:
  fs/nfsd/export.c: Adjust error handling code involving auth_domain_put
  MAINTAINERS: mention lockd and sunrpc in nfs entries
  lockd: trivial sparse endian annotations
2008-08-12 16:39:22 -07:00
Miklos Szeredi
bde74e4bc6 locks: add special return value for asynchronous locks
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>
2008-07-25 10:53:47 -07:00
Miklos Szeredi
cc77b1521d lockd: dont return EAGAIN for a permanent error
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>
2008-07-25 10:53:47 -07:00
Harvey Harrison
317602f3e0 lockd: trivial sparse endian annotations
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>
2008-07-23 07:38:04 -04:00
Linus Torvalds
14b395e35d Merge branch 'for-2.6.27' of git://linux-nfs.org/~bfields/linux
* '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
  ...
2008-07-20 21:21:46 -07:00
Trond Myklebust
a86dc496b7 SUNRPC: Remove the BKL from the callback functions
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>
2008-07-15 18:10:57 -04:00
Felix Blyakher
d67d1c7bf9 nfs: set correct fl_len in nlmclnt_test()
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>
2008-07-15 18:08:59 -04:00
Chuck Lever
367c8c7bd9 lockd: Pass "struct sockaddr *" to new failover-by-IP function
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>
2008-07-15 16:11:29 -04:00
J. Bruce Fields
560de0e659 lockd: get host reference in nlmsvc_create_block() instead of callers
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>
2008-07-15 15:40:25 -04:00
J. Bruce Fields
6d7bbbbacc lockd: minor svclock.c style fixes
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-15 15:28:43 -04:00
Jeff Layton
6cde4de807 lockd: eliminate duplicate nlmsvc_lookup_host call from nlmsvc_lock
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>
2008-07-15 14:53:33 -04:00
Jeff Layton
8f920d5e29 lockd: eliminate duplicate nlmsvc_lookup_host call from nlmsvc_testlock
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>
2008-07-15 14:26:52 -04:00
Jeff Layton
b0e92aae15 lockd: nlm_release_host() checks for NULL, caller needn't
No need to check for a NULL argument twice.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-07-15 12:35:20 -04:00
Jeff Layton
abd1ec4efd lockd: close potential race with rapid lockd_up/lockd_down cycle
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>
2008-06-23 13:02:50 -04:00
Harvey Harrison
8e24eea728 fs: replace remaining __FUNCTION__ occurrences
__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>
2008-04-30 08:29:54 -07:00
J. Bruce Fields
1a747ee0cc locks: don't call ->copy_lock methods on return of conflicting locks
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>
2008-04-25 13:00:11 -04:00
Wendy Cheng
17efa372cf lockd: unlock lockd locks held for a certain filesystem
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(-)
2008-04-25 13:00:11 -04:00
Wendy Cheng
4373ea84c8 lockd: unlock lockd locks associated with a given server ip
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(-)
2008-04-25 13:00:10 -04:00
Linus Torvalds
563307b2fa Merge git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 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
  ...
2008-04-24 11:46:16 -07:00
Jeff Layton
f97c650dda NLM: don't let lockd exit on unexpected svc_recv errors (try #2)
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>
2008-04-23 16:13:43 -04:00
J. Bruce Fields
3c61eecb60 lockd: Fix stale nlmsvc_unlink_block comment
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>
2008-04-23 16:13:42 -04:00
J. Bruce Fields
d842120212 lockd: convert nsm_mutex to a spinlock
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>
2008-04-23 16:13:39 -04:00
J. Bruce Fields
a95e56e72c lockd: clean up __nsm_find()
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>
2008-04-23 16:13:39 -04:00
J. Bruce Fields
164f98adbb lockd: fix race in nlm_release()
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>
2008-04-23 16:13:39 -04:00
Harvey Harrison
93245d11fc lockd: fix sparse warning in svcshare.c
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>
2008-04-23 16:13:39 -04:00
Jeff Layton
d751a7cd06 NLM: Convert lockd to use kthreads
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>
2008-04-23 16:13:36 -04:00
NeilBrown
1447d25eb3 knfsd: Remove NLM_HOST_MAX and associated logic.
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>
2008-04-23 16:13:35 -04:00
Trond Myklebust
d11d10cc05 NLM/lockd: Ensure client locking calls use correct credentials
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>
2008-04-19 16:54:43 -04:00
Trond Myklebust
5f50c0c6d6 NLM/lockd: Fix a race when cancelling a blocking lock
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>
2008-04-19 16:53:49 -04:00
Trond Myklebust
6b4b3a752b NLM/lockd: Ensure that nlmclnt_cancel() returns results of the CANCEL call
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>
2008-04-19 16:53:45 -04:00
Trond Myklebust
8ec7ff7444 NLM: Remove the signal masking in nlmclnt_proc/nlmclnt_cancel
The signal masks have been rendered obsolete by the preceding patch.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-04-19 16:53:42 -04:00
Trond Myklebust
dc9d8d0481 NLM/lockd: convert __nlm_async_call to use rpc_run_task()
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>
2008-04-19 16:53:39 -04:00
Trond Myklebust
5e7f37a76f NLM/lockd: Add a reference counter to struct nlm_rqst
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>
2008-04-19 16:53:36 -04:00