This patch provides the RPC layer helper functions to allow NFS to manage
data in the face of expired credentials - such as avoiding buffered WRITEs
and COMMITs when the gss context will expire before the WRITEs are flushed
and COMMITs are sent.

These helper functions enable checking the expiration of an underlying
credential key for a generic rpc credential, e.g. the gss_cred gss context
gc_expiry which for Kerberos is set to the remaining TGT lifetime.

A new rpc_authops key_timeout is only defined for the generic auth.
A new rpc_credops crkey_to_expire is only defined for the generic cred.
A new rpc_credops crkey_timeout is only defined for the gss cred.

Set a credential key expiry watermark, RPC_KEY_EXPIRE_TIMEO set to 240 seconds
as a default and can be set via a module parameter as we need to ensure there
is time for any dirty data to be flushed.

If key_timeout is called on a credential with an underlying credential key that
will expire within watermark seconds, we set the RPC_CRED_KEY_EXPIRE_SOON
flag in the generic_cred acred so that the NFS layer can clean up prior to
key expiration.

Checking a generic credential's underlying credential involves a cred lookup.
To avoid this lookup in the normal case when the underlying credential has
a key that is valid (before the watermark), a notify flag is set in
the generic credential the first time the key_timeout is called. The
generic credential then stops checking the underlying credential key expiry, and
the underlying credential (gss_cred) match routine then checks the key
expiration upon each normal use and sets a flag in the associated generic
credential only when the key expiration is within the watermark.
This in turn signals the generic credential key_timeout to perform the extra
credential lookup thereafter.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

The NFS layer needs to know when a key has expired.
This change also returns -EKEYEXPIRED to the application, and the informative
"Key has expired" error message is displayed. The user then knows that
credential renewal is required.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Ensure that we set rpc_clnt->cl_parent before calling rpc_client_register
so that rpcauth_create can find any existing RPCSEC_GSS caches for this
transport.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Ensure that all struct rpc_clnt for any given socket/rdma channel
share the same RPCSEC_GSS/krb5,krb5i,krb5p caches.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Ensure that if an rpc_clnt owns more than one RPCSEC_GSS-based authentication
mechanism, then those caches will share the same 'gssd' upcall pipe.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Add support for looking up existing objects and creating new ones if there
is no match.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

It is now redundant.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

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

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

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

The current system requires everyone to set up notifiers, manage directory
locking, etc.
What we really want to do is have the rpc_client create its directory,
and then create all the entries.

This patch will allow the RPCSEC_GSS and NFS code to register all the
objects that they want to have appear in the directory, and then have
the sunrpc code call them back to actually create/destroy their pipefs
dentries when the rpc_client creates/destroys the parent.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Ensure that __nfs_idmap_unregister can be called twice without
consequences.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

If an error condition occurs on rpc_pipefs creation, or the user mounts
rpc_pipefs and then unmounts it, then the dentries in struct gss_auth
need to be reset to NULL so that a second call to gss_pipes_dentries_destroy
doesn't try to free them again.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Don't pass the rpc_client as a parameter, when what we really want is
the net namespace.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

The clnt->cl_principal is being used exclusively to store the service
target name for RPCSEC_GSS/krb5 callbacks. Replace it with something that
is stored only in the RPCSEC_GSS-specific code.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Optimise away gss_encode_msg: we don't need to look up the pipe
version a second time.

Save the gss target name in struct gss_auth. It is a property of the
auth cache itself, and doesn't really belong in the rpc_client.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

The directory name is _always_ clnt->cl_program->pipe_dir_name.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

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

It just duplicates the cl_program->name, and is not used in any fast
paths where the extra dereference will cause a hit.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

We don't want to pass the context argument to trace_nfs_atomic_open_exit()
after it has been released.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

After reclaiming state that was lost, the NFS client tries to reclaim
any locks, and then checks that each one has NFS_LOCK_INITIALIZED set
(which means that the server has confirmed the lock).
However if the client holds a delegation, nfs_reclaim_locks() simply aborts
(or more accurately it called nfs_lock_reclaim() and that returns without
doing anything).

This is because when a delegation is held, the server doesn't need to
know about locks.

So if a delegation is held, NFS_LOCK_INITIALIZED is not expected, and
its absence is certainly not an error.

So don't print the warnings if NFS_DELGATED_STATE is set.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Add tracepoints to detect issues with the TEST_STATEID operation.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Add tracepoints to nfs41_setup_sequence and nfs41_sequence_done
to track session and slot table state changes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

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

Set up tracepoints to track read, write and commit, as well as
pNFS reads and writes and commits to the data server.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

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

Add tracepoints to help debug uid/gid mappings to username/group.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Set up tracepoints to track when delegations are set, reclaimed,
returned by the client, or recalled by the server.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Add tracepoints to debug renames.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Set up basic tracepoints for debugging NFSv4 setattr, access,
readlink, readdir, get_acl set_acl get_security_label,
and set_security_label.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Set up basic tracepoints for debugging NFSv4 lookup, unlink/remove,
symlink, mkdir, mknod, fs_locations and secinfo.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Set up basic tracepoints for debugging NFSv4 file lock/unlock
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Set up basic tracepoints for debugging NFSv4 file open/close
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Set up basic tracepoints for debugging client id creation/destruction
and session creation/destruction.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

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

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

Add tracepoints for mknod, mkdir, rmdir, remove (unlink) and symlink.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

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

Add tracepoints for lookup, lookup_revalidate and atomic_open
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

When doing an open of a directory, ensure that we do pass the lookup flags
from nfs_atomic_open into nfs_lookup.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>