This patch makes main step in NFSd containerisation.

There could be different approaches to how to make NFSd able to handle
incoming RPC request from different network namespaces.  The two main
options are:

1) Share NFSd kthreads betwween all network namespaces.
2) Create separated pool of threads for each namespace.

While first approach looks more flexible, second one is simpler and
non-racy.  This patch implements the second option.

To make it possible to allocate separate pools of threads, we have to
make it possible to allocate separate NFSd service structures per net.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

This is simple: an NFSd service can be started at different times in
different network environments. So, its "boot time" has to be assigned
per net.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

This patch introduces introduces per-net "nfsd_net_up" boolean flag, which has
the same purpose as general "nfsd_up" flag - skip init or shutdown of per-net
resources in case of they are inited on shutted down respectively.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

NFSd resources are partially per-net and partially globally used.
This patch splits resources init and shutdown and moves per-net code to
separated functions.
Generic and per-net init and shutdown are called sequentially for a while.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Precursor patch. Hard-coded "init_net" will be replaced by proper one in
future.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Precursor patch. Hard-coded "init_net" will be replaced by proper one in
future.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Precursor patch. Hard-coded "init_net" will be replaced by proper one in
future.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Precursor patch. Hard-coded "init_net" will be replaced by proper one in
future.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Precursor patch. Hard-coded "init_net" will be replaced by proper one in
future.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Precursor patch. Hard-coded "init_net" will be replaced by proper one in
future.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

There could be a situation, when NFSd was started in one network namespace, but
stopped in another one.
This will trigger kernel panic, because RPCBIND client is stored on per-net
NFSd data, and will be NULL on NFSd shutdown.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

With NFSv4, if we create a file then open it we explicit avoid checking
the permissions on the file during the open because the fact that we
created it ensures we should be allow to open it (the create and the
open should appear to be a single operation).

However if the reply to an EXCLUSIVE create gets lots and the client
resends the create, the current code will perform the permission check -
because it doesn't realise that it did the open already..

This patch should fix this.

Note that I haven't actually seen this cause a problem.  I was just
looking at the code trying to figure out a different EXCLUSIVE open
related issue, and this looked wrong.

(Fix confirmed with pynfs 4.0 test OPEN4--bfields)

Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
[bfields: use OWNER_OVERRIDE and update for 4.1]
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

This is a cleanup patch.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Pointer to client tracking operations - client_tracking_ops - have to be
containerized, because different environment can support different trackers
(for example, legacy tracker currently is not suported in container).
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Fix nfsd4_lockt and release_lockowner to lookup the referenced client,
so that it can renew it, or correctly return "expired", as appropriate.

Also share some code while we're here.
Reported-by: Frank Filz <ffilzlnx@us.ibm.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Over TCP, RPC's are preceded by a single 4-byte field telling you how
long the rpc is (in bytes).  The spec also allows you to send an RPC in
multiple such records (the high bit of the length field is used to tell
you whether this is the final record).

We've survived for years without supporting this because in practice the
clients we care about don't use it.  But the userland rpc libraries do,
and every now and then an experimental client will run into this.  (Most
recently I noticed it while trying to write a pynfs check.)  And we're
really on the wrong side of the spec here--let's fix this.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Keep a separate field, sk_datalen, that tracks only the data contained
in a fragment, not including the fragment header.

For now, this is always just max(0, sk_tcplen - 4), but after we allow
multiple fragments sk_datalen will accumulate the total rpc data size
while sk_tcplen only tracks progress receiving the current fragment.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The full reclen doesn't include the fragment header, but sk_tcplen does.
Fix this to make it an apples-to-apples comparison.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Soon we want to support multiple fragments, in which case it may be
legal for a single fragment to be smaller than 8 bytes, so we'll want to
delay this check till we've reached the last fragment.

Also fix an outdated comment.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Byte-swapping in place is always a little dubious.

Let's instead define this field to always be big-endian, and do the
swapping on demand where we need it.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Write the client's ip address to any state file and all appropriate
state for that client will be forgotten.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Controlling the read and write functions allows me to add in "forget
client w.x.y.z", since we won't be limited to reading and writing only
u64 values.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

I also log basic information that I can figure out about the type of
state (such as number of locks for each client IP address).  This can be
useful for checking that state was actually dropped and later for
checking if the client was able to recover.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

The eventual goal is to forget state based on ip address, so it makes
sense to call this function in a for-each-client loop until the correct
amount of state is forgotten.  I also use this patch as an opportunity
to rename the forget function from "func()" to "forget()".
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Once I have a client, I can easily use its delegation list rather than
searching the file hash table for delegations to remove.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Using "forget_n_state()" forces me to implement the code needed to
forget a specific client's openowners.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

I use the new "forget_n_state()" function to iterate through each client
first when searching for locks.  This may slow down forgetting locks a
little bit, but it implements most of the code needed to forget a
specified client's locks.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

I added in a generic for-each loop that takes a pass over the client_lru
list for the current net namespace and calls some function.  The next few
patches will update other operations to use this function as well.  A value
of 0 still means "forget everything that is found".
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Each function touches state in some way, so getting the lock earlier
can help simplify code.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

There were only a small number of functions in this file and since they
all affect stored state I think it makes sense to put them in state.h
instead.  I also dropped most static inline declarations since there are
no callers when fault injection is not enabled.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Grace time is a part of NFSv4 state engine, which is constructed per network
namespace.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Lease time is a part of NFSv4 state engine, which is constructed per network
namespace.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

This is a cleanup patch. Functions nfsd_pool_stats_open() and
nfsd_pool_stats_release() are declared in fs/nfsd/nfsd.h.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Flag in_grace is a part of client tracking state, which is network namesapce
aware. So let'a replace global static variable with per-net one.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Opening and closing of this file is done in client tracking init and exit
operations.
Client tracking is done in network namespace context already. So let's make
this file opened and closed per network context - this will simlify it's
management.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

Split NFSv4 state init and shutdown into two different calls: per-net one and
generic one.
Per-net cwinit/shutdown pair have to be called for any namespace, generic pair
- only once on NSFd kthreads start and shutdown respectively.

Refresh of diff-nfsd-call-state-init-twice
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

This patch renames nfs4_state_start_net() into nfs4_state_create_net(), where
get_net() now performed.
Also it introduces new nfs4_state_start_net(), which is now responsible for
state creation and initializing all per-net data and which is now called from
nfs4_state_start().
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

This patch renames __nfs4_state_shutdown_net() into nfs4_state_shutdown_net(),
__nfs4_state_shutdown() into nfs4_state_shutdown_net() and moves all network
related shutdown operations to nfs4_state_shutdown_net().
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

NFSv4 delegations are stored in global list. But they are nfs4_client
dependent, which is network namespace aware already.
State shutdown and laundromat are done per network namespace as well.
So, delegations unhash have to be done in network namespace context.
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>