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: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up: Now that lockd_up() starts listeners for both transports, the
"proto" argument is no longer needed.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: NJ. 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: NJ. 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: NChuck 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: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond 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: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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: NMarc Eshel <eshel@almaden.ibm.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Annotated, all places switched to keeping status net-endian.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

It is possible for the ->fopen callback from lockd into nfsd to find that an
answer cannot be given straight away (an upcall is needed) and so the request
has to be 'dropped', to be retried later.  That error status is not currently
propagated back.

So:
  Change nlm_fopen to return nlm error codes (rather than a private
  protocol) and define a new nlm_drop_reply code.
  Cause nlm_drop_reply to cause the rpc request to get rpc_drop_reply
  when this error comes back.
  Cause svc_process to drop a request which returns a status of
  rpc_drop_reply.

[akpm@osdl.org: fix warning storm]
Cc: Marc Eshel <eshel@almaden.ibm.com>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Currently lockd listens on UDP always, and TCP if CONFIG_NFSD_TCP is set.

However as lockd performs services of the client as well, this is a problem.
If CONFIG_NfSD_TCP is not set, and a tcp mount is used, the server will not be
able to call back to lockd.

So:
 - add an option to lockd_up saying which protocol is needed
 - Always open sockets for which an explicit port was given, otherwise
   only open a socket of the type required
 - Change nfsd to do one lockd_up per socket rather than one per thread.

This
 - removes the dependancy on CONFIG_NFSD_TCP
 - means that lockd may open sockets other than at startup
 - 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.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!