Commit Graph

77 Commits

Author SHA1 Message Date
Thomas Gleixner 5eaaed4fe2 fs: lockd: Use ktime_get_ns()
Replace the ever recurring:
        ts = ktime_get_ts();
        ns = timespec_to_ns(&ts);
with
        ns = ktime_get_ns();

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2014-07-23 15:01:44 -07:00
Jeff Layton 5976687a2b sunrpc: move address copy/cmp/convert routines and prototypes from clnt.h to addr.h
These routines are used by server and client code, so having them in a
separate header would be best.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-02-05 09:41:14 -05:00
Trond Myklebust 326ce0a6da lockd: Remove trivial BUG_ON()s from the NSM code
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-11-04 14:43:39 -05:00
Trond Myklebust e498daa812 LOCKD: Clear ln->nsm_clnt only when ln->nsm_users is zero
The current code is clearing it in all cases _except_ when zero.

Reported-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
2012-10-24 10:46:22 -04:00
Trond Myklebust a4ee8d978e LOCKD: fix races in nsm_client_get
Commit e9406db20f (lockd: per-net
NSM client creation and destruction helpers introduced) contains
a nasty race on initialisation of the per-net NSM client because
it doesn't check whether or not the client is set after grabbing
the nsm_create_mutex.

Reported-by: Nix <nix@esperi.org.uk>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
2012-10-24 10:46:22 -04:00
Stanislav Kinsbursky cb7323fffa lockd: create and use per-net NSM RPC clients on MON/UNMON requests
NSM RPC client can be required on NFSv3 umount, when child reaper is dying
(and destroying it's mount namespace). It means, that current nsproxy is set
to NULL already, but creation of RPC client requires UTS namespace for gaining
hostname string.

This patch creates reference-counted per-net NSM client on first monitor
request and destroys it after last unmonitor request.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-10-01 15:27:43 -07:00
Stanislav Kinsbursky 303a7ce920 lockd: use rpc client's cl_nodename for id encoding
Taking hostname from uts namespace if not safe, because this cuold be
performind during umount operation on child reaper death. And in this case
current->nsproxy is NULL already.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-10-01 15:27:38 -07:00
Stanislav Kinsbursky e9406db20f lockd: per-net NSM client creation and destruction helpers introduced
NSM RPC client can be required on NFSv3 umount, when child reaper is dying (and
destroying it's mount namespace). It means, that current nsproxy is set to
NULL already, but creation of RPC client requires UTS namespace for gaining
hostname string.
This patch introduces reference counted NFS RPC clients creation and
destruction helpers (similar to RPCBIND RPC clients).

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-10-01 15:27:34 -07:00
Stanislav Kinsbursky 0e1cb5c0aa LockD: make NSM network namespace aware
NLM host is network namespace aware now.
So NSM have to take it into account.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-15 00:19:48 -05:00
Trond Myklebust a613fa168a SUNRPC: constify the rpc_program
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31 19:28:20 -05:00
Rusty Russell 90ab5ee941 module_param: make bool parameters really bool (drivers & misc)
module_param(bool) used to counter-intuitively take an int.  In
fddd5201 (mid-2009) we allowed bool or int/unsigned int using a messy
trick.

It's time to remove the int/unsigned int option.  For this version
it'll simply give a warning, but it'll break next kernel version.

Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2012-01-13 09:32:20 +10:30
Chuck Lever bf2695516d SUNRPC: New xdr_streams XDR decoder API
Now that all client-side XDR decoder routines use xdr_streams, there
should be no need to support the legacy calling sequence [rpc_rqst *,
__be32 *, RPC res *] anywhere.  We can construct an xdr_stream in the
generic RPC code, instead of in each decoder function.

This is a refactoring change.  It should not cause different behavior.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-12-16 12:37:25 -05:00
Chuck Lever 9f06c719f4 SUNRPC: New xdr_streams XDR encoder API
Now that all client-side XDR encoder routines use xdr_streams, there
should be no need to support the legacy calling sequence [rpc_rqst *,
__be32 *, RPC arg *] anywhere.  We can construct an xdr_stream in the
generic RPC code, instead of in each encoder function.

Also, all the client-side encoder functions return 0 now, making a
return value superfluous.  Take this opportunity to convert them to
return void instead.

This is a refactoring change.  It should not cause different behavior.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-12-16 12:37:25 -05:00
Chuck Lever 49b170047f NSM: Avoid return code checking in NSM XDR encoder functions
Clean up.

The trend in the other XDR encoder functions is to BUG() when encoding
problems occur, since a problem here is always due to a local coding
error.  Then, instead of a status, zero is unconditionally returned.

Update the NSM XDR encoders to behave this way.

To finish the update, use the new-style be32_to_cpup() and
cpu_to_be32() macros, and compute the buffer sizes using raw integers
instead of sizeof().  This matches the conventions used in other XDR
functions

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-12-16 12:37:24 -05:00
Pavel Emelyanov c653ce3f0a sunrpc: Add net to rpc_create_args
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2010-10-01 17:18:56 -04:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Jeff Layton 7e469af97e lockd: don't clear sm_monitored on nsm_reboot_lookup
When lockd gets a notify downcall from statd, it'll search its hosts
cache and then clear the sm_monitored bit on the host it finds. The idea
is apparently to make lockd redo a SM_MON on the next lock request.

This is unnecessary and causes the kernel's NSM cache to go out of sync
with statd. statd doesn't stop monitoring a host when it gets a
SM_NOTIFY and there's no guarantee that another lock will occur after
the reclaim and before the unmount. In that event, no SM_UNMON will
occur.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-02-08 16:20:35 -05:00
Jeff Layton 4516fc0454 sunrpc: add routine for comparing addresses
lockd needs these sort of routines, as does the NFSv4 callback code.

Move lockd's routines into common code and rename them so that they can
be used by others.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-08-21 11:27:42 -04:00
Chuck Lever c15128c5e4 lockd: Replace nsm_display_address() with rpc_ntop()
Clean up.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-08-09 15:09:39 -04:00
Chuck Lever 0e5c2632e1 lockd: Don't bother with RPC ping for NSM upcalls
Cut NSM upcall RPC traffic in half -- don't do a NULL call first.
The cases where a ping would be helpful are rare.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-17 18:02:11 -07:00
Chuck Lever 6c9dc42551 lockd: Update NSM state from SM_MON replies
When rpc.statd starts up in user space at boot time, it attempts to
write the latest NSM local state number into
/proc/sys/fs/nfs/nsm_local_state.

If lockd.ko isn't loaded yet (as is the case in most configurations),
that file doesn't exist, thus the kernel's NSM state remains set to
its initial value of zero during lockd operation.

This is a problem because rpc.statd and lockd use the NSM state number
to prevent repeated lock recovery on rebooted hosts.  If lockd sends
a zero NSM state, but then a delayed SM_NOTIFY with a real NSM state
number is received, there is no way for lockd or rpc.statd to
distinguish that stale SM_NOTIFY from an actual reboot.  Thus lock
recovery could be performed after the rebooted host has already
started reclaiming locks, and those locks will be lost.

We could change /etc/init.d/nfslock so it always modprobes lockd.ko
before starting rpc.statd.  However, if lockd.ko is ever unloaded
and reloaded, we are back at square one, since the NSM state is not
preserved across an unload/reload cycle.  This may happen frequently
on clients that use automounter.  A period of NFS inactivity causes
lockd.ko to be unloaded, and the kernel loses its NSM state setting.

Instead, let's use the fact that rpc.statd plants the local system's
NSM state in every SM_MON (and SM_UNMON) reply.  lockd performs a
synchronous SM_MON upcall to the local rpc.statd _before_ sending its
first NLM request to a new remote.  This would permit rpc.statd to
provide the current NSM state to lockd, even after lockd.ko had been
unloaded and reloaded.

Note that NLMPROC_LOCK arguments are constructed before the
nsm_monitor() call, so we have to rearrange argument construction very
slightly to make this all work out.

And, the kernel appears to treat NSM state as a u32 (see struct
nlm_args and nsm_res).  Make nsm_local_state a u32 as well, to ensure
we don't get bogus comparison results.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-06-17 18:02:10 -07:00
Mans Rullgard ad5b365c12 NSM: Fix unaligned accesses in nsm_init_private()
This fixes unaligned accesses in nsm_init_private() when
creating nlm_reboot keys.

Signed-off-by: Mans Rullgard <mans@mansr.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-04-01 13:24:14 -04:00
Chuck Lever 49b5699b3f NSM: Move nsm_create()
Clean up: one last thing... relocate nsm_create() to eliminate the forward
declaration and group it near the only function that actually uses it.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:56 -05:00
Chuck Lever b7ba597fb9 NSM: Move nsm_use_hostnames to mon.c
Clean up.

Treat the nsm_use_hostnames global variable like nsm_local_state.
Note that the default value of nsm_use_hostnames is still zero.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:55 -05:00
Chuck Lever 8529bc51d3 NSM: Move nsm_addr() to fs/lockd/mon.c
Clean up: nsm_addr_in() is no longer used, and nsm_addr() is used only in
fs/lockd/mon.c, so move it there.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:55 -05:00
Chuck Lever e6765b8397 NSM: Remove include/linux/lockd/sm_inter.h
Clean up: The include/linux/lockd/sm_inter.h header is nearly empty
now.  Remove it.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:55 -05:00
Chuck Lever 94da7663db NSM: Replace IP address as our nlm_reboot lookup key
NLM provides file locking services for NFS files.  Part of this service
includes a second protocol, known as NSM, which is a reboot
notification service.  NLM uses this service to determine when to
reclaim locks or enter a grace period after a client or server reboots.

The NLM service (implemented by lockd in the Linux kernel) contacts
the local NSM service (implemented by rpc.statd in Linux user space)
via NSM protocol upcalls to register a callback when a particular
remote peer reboots.

To match the callback to the correct remote peer, the NLM service
constructs a cookie that it passes in the request.  The NSM service
passes that cookie back to the NLM service when it is notified that
the given remote peer has indeed rebooted.

Currently on Linux, the cookie is the raw 32-bit IPv4 address of the
remote peer.  To support IPv6 addresses, which are larger, we could
use all 16 bytes of the cookie to represent a full IPv6 address,
although we still can't represent an IPv6 address with a scope ID in
just 16 bytes.

Instead, to avoid the need for future changes to support additional
address types, we'll use a manufactured value for the cookie, and use
that to find the corresponding nsm_handle struct in the kernel during
the NLMPROC_SM_NOTIFY callback.

This should provide complete support in the kernel's NSM
implementation for IPv6 hosts, while remaining backwards compatible
with older rpc.statd implementations.

Note we also deal with another case where nsm_use_hostnames can change
while there are outstanding notifications, possibly resulting in the
loss of reboot notifications.  After this patch, the priv cookie is
always used to lookup rebooted hosts in the kernel.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:55 -05:00
Chuck Lever 77a3ef33e2 NSM: More clean up of nsm_get_handle()
Clean up: refactor nsm_get_handle() so it is organized the same way that
nsm_reboot_lookup() is.

There is an additional micro-optimization here.  This change moves the
"hostname & nsm_use_hostnames" test out of the list_for_each_entry()
clause in nsm_get_handle(), since it is loop-invariant.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:55 -05:00
Chuck Lever b39b897c25 NSM: Refactor nsm_handle creation into a helper function
Clean up.  Refactor the creation of nsm_handles into a helper.  Fields
are initialized in increasing address order to make efficient use of
CPU caches.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06 11:53:55 -05:00
Chuck Lever 92fd91b998 NLM: Remove "create" argument from nsm_find()
Clean up: nsm_find() now has only one caller, and that caller
unconditionally sets the @create argument. Thus the @create
argument is no longer needed.

Since nsm_find() now has a more specific purpose, pick a more
appropriate name for it.

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 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 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