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: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

To store larger addresses in the nlm_host structure, make h_addr a
sockaddr_storage, and add an address length field.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Knowing which source address is used for communicating with remote NLM
services can be helpful for debugging configuration problems on hosts
with multiple addresses.

Keep the dprintk debugging here, but adapt it so it displays AF_INET6
addresses properly.  There are also a couple of dprintk clean-ups as
well.

At some point we will aggregate the helpers that display presentation
format addresses into a single set of shared helpers.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

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: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

nlmsvc_lock calls nlmsvc_lookup_host to find a nlm_host struct. The
callers of this function, however, call nlmsvc_retrieve_args or
nlm4svc_retrieve_args, which also return a nlm_host struct.

Change nlmsvc_lock to take a host arg instead of calling
nlmsvc_lookup_host itself and change the callers to pass a pointer to
the nlm_host they've already found.

Since nlmsvc_testlock() now just uses the caller's reference, we no
longer need to get or release it.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

nlmsvc_testlock calls nlmsvc_lookup_host to find a nlm_host struct. The
callers of this functions, however, call nlmsvc_retrieve_args or
nlm4svc_retrieve_args, which also return a nlm_host struct.

Change nlmsvc_testlock to take a host arg instead of calling
nlmsvc_lookup_host itself and change the callers to pass a pointer to
the nlm_host they've already found.

We take a reference to host in the place where nlmsvc_testlock()
previous did a new lookup, so the reference counting is unchanged from
before.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

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: NS. Wendy Cheng <wcheng@redhat.com>
Cc: Lon Hohberger  <lhh@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

 fs/lockd/svcsubs.c          |   66 +++++++++++++++++++++++++++++++++++++++-----
 fs/nfsd/nfsctl.c            |   65 +++++++++++++++++++++++++++++++++++++++++++
 include/linux/lockd/lockd.h |    7 ++++
 3 files changed, 131 insertions(+), 7 deletions(-)

For high-availability NFS service, we generally need to be able to drop
file locks held on the exported filesystem before moving clients to a
new server.  Currently the only way to do that is by shutting down lockd
entirely, which is often undesireable (for example, if you want to
continue exporting other filesystems).

This patch allows the administrator to release all locks held by clients
accessing the client through a given server ip address, by echoing that
address to a new file, /proc/fs/nfsd/unlock_ip, as in:

shell> echo 10.1.1.2 > /proc/fs/nfsd/unlock_ip

The expected sequence of events can be:
1. Tear down the IP address
2. Unexport the path
3. Write IP to /proc/fs/nfsd/unlock_ip to unlock files
4. Signal peer to begin take-over.

For now we only support IPv4 addresses and NFSv2/v3 (NFSv4 locks are not
affected).

Also, if unmounting the filesystem is required, we assume at step 3 that
clients using the given server ip are the only clients holding locks on
the given filesystem; otherwise, an additional patch is required to
allow revoking all locks held by lockd on a given filesystem.
Signed-off-by: NS. Wendy Cheng <wcheng@redhat.com>
Cc: Lon Hohberger  <lhh@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NJ. 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(-)

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: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean-up: replace  __inline__ and use up-to-date function declaration
conventions.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up: RPC protocol version numbers are u32.  Make sure we use an
appropriate type for NLM version numbers when calling nlm_lookup_host().

Eliminates a harmless mixed sign comparison in nlm_host_lookup().
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

According to The Open Group's NLM specification, NLM callers are variable
length strings.  XDR variable length strings use an unsigned 32 bit length.
And internally, negative string lengths are not meaningful for the Linux
NLM implementation.

Clean up: Make nlm_lock.len and nlm_reboot.len unsigned integers.  This
makes the sign of NLM string lengths consistent with the sign of xdr_netobj
lengths.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Acked-By: NNeilBrown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Use the destination address of the original NLM request as the
source address in callbacks to the client.
Signed-off-by: NFrank van Maarseveen <frankvm@frankvm.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Change NLM internal interface to pass more information for test lock; we
need this to make sure the cookie information is pushed down to the place
where we do request deferral, which is handled for testlock by the
following patch.
Signed-off-by: NMarc Eshel <eshel@almaden.ibm.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

We need to keep some state for a pending asynchronous lock request, so this
patch adds that state to struct nlm_block.

This also adds a function which defers the request, by calling
rqstp->rq_chandle.defer and storing the resulting deferred request in a
nlm_block structure which we insert into lockd's global block list.  That
new function isn't called yet, so it's dead code until a later patch.
Signed-off-by: NMarc Eshel <eshel@almaden.ibm.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

NLM version 4 requests estimate the call and reply header sizes rather
conservatively, using the very maximum size allowed in the protocol even
though Linux always uses only a small fraction of the allowable space.

Reduce the size of caller and lock arguments to conserve RPC buffer space
while XDR encoding NLM4 arguments.  Add compile-time checks to ensure the
hostname string won't overflow NLM protocol maximums.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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>

Signed-off-by: NJosef Sipek <jsipek@fsl.cs.sunysb.edu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Make the following needlessly global functions static:

 - nlm_lookup_host()
 - nsm_find()
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Both the (recently introduces) nsm_sema and the older f_sema are converted
over.

Cc: Olaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

When we send a GRANTED_MSG call, we current copy the NLM cookie provided in
the original LOCK call - because in 1996, some broken clients seemed to rely
on this bug.  However, this means the cookies are not unique, so that when the
client's GRANTED_RES message comes back, we cannot simply match it based on
the cookie, but have to use the client's IP address in addition.  Which breaks
when you have a multi-homed NFS client.

The X/Open spec explicitly mentions that clients should not expect the same
cookie; so one may hope that any clients that were broken in 1996 have either
been fixed or rendered obsolete.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The way we incremented the NLM cookie in nlmclnt_next_cookie was not thread
safe.  This patch changes the counter to an atomic_t
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch adds the nsm_use_hostnames sysctl and module param.  If set, lockd
will use the client's name (as given in the NLM arguments) to find the NSM
handle.  This makes recovery work when the NFS peer is multi-homed, and the
reboot notification arrives from a different IP than the original lock calls.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

As a result of previous patches, the loop in nlmsvc_invalidate_all just sets
h_expires for all client/hosts to 0 (though does it in a very complicated
way).

This was possibly meant to trigger early garbage collection but half the time
'0' is in the future and so it infact delays garbage collection.

Pre-aging the 'hosts' is not really needed at this point anyway so we throw
out the loop and nlm_find_client which is no longer needed.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch makes nlm_traverse{locks,blocks,shares} and friends use a function
pointer rather than a "action" enum.

This function pointer is given two nlm_hosts (one given by the caller, the
other taken from the lock/block/share currently visited), and is free to do
with them as it wants.  If it returns a non-zero value, the lockd/block/share
is released.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This changes struct nlm_file and the nlm_files hash table to use a hlist
instead of the home-grown lists.

This allows us to remove f_hash which was only used to find the right hash
chain to delete an entry from.

It also increases the size of the nlm_files hash table from 32 to 128.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch changes the nlm_blocked list to use a list_node instead of
homegrown linked list handling.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Get rid of the home-grown singly linked lists for the nlm_host hash table.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch makes the SM_NOTIFY handling understand and use the nsm_handle.

To make it a bit clear what is happening:

    nlmclent_prepare_reclaim and nlmclnt_finish_reclaim
    get open-coded into 'reclaimer'

The result is tidied up.

Then some of that functionality is moved out into nlm_host_rebooted (which
calls nlmclnt_recovery which starts a thread which runs reclaimer).

Also host_rebooted now finds an nsm_handle rather than a host, then then
iterates over all hosts and deals with each host that shares that nsm_handle.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch introduces the nsm_handle, which is shared by all nlm_host objects
referring to the same client.

With this patch applied, all nlm_hosts from the same address will share the
same nsm_handle.  A future patch will add sharing by name.

Note: this patch changes h_name so that it is no longer guaranteed to be an IP
address of the host.  When the host represents an NFS server, h_name will be
the name passed in the mount call.  When the host represents a client, h_name
will be the name presented in the lock request received from the client.  A
h_name is only used for printing informational messages, this change should
not be significant.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch adds the peer's hostname (and name length) to all calls to
nlm*_lookup_host functions.  A subsequent patch will make use of these (is
requested by a sysctl).
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Common code from nlm4svc_proc_sm_notify and nlmsvc_proc_sm_notify is moved
into a new nlm_host_rebooted.

This is in preparation of a patch that will change the reboot notification
handling entirely.
Signed-off-by: NOlaf Kirch <okir@suse.de>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Replace references to system_utsname to the per-process uts namespace
where appropriate.  This includes things like uname.

Changes: Per Eric Biederman's comments, use the per-process uts namespace
	for ELF_PLATFORM, sunrpc, and parts of net/ipv4/ipconfig.c

[jdike@addtoit.com: UML fix]
[clg@fr.ibm.com: cleanup]
[akpm@osdl.org: build fix]
Signed-off-by: NSerge E. Hallyn <serue@us.ibm.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Andrey Savochkin <saw@sw.ru>
Signed-off-by: NCedric Le Goater <clg@fr.ibm.com>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We never actually set the b_done field any more; it's always zero.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from af8412d4283ef91356e65e0ed9b025b376aebded commit)

Currently it is possible for a task to remove its locks at the same time as
the NLM recovery thread is trying to recover them. This quickly leads to an
Oops.
Protect the locks using an rw semaphore while they are being recovered.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add the fl_owner to NLM compare locks. Since two different client can
present the same pid to the server it is not enough to distinguish locks
from different clients. The fl_owner field is a pointer to the struct
nlm_host which is unique for each client.
Signed-off-by: NMarc Eshel <eshel@almaden.ibm.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>

Note that we never return non-zero.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>