Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Rather than implementing this twice for NFS v4.0 and v4.1
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

This puts the check in a single place, rather than needing to implement
it twice for v4.0 and v4.1.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

The inline ifdef lets us put everything in a single place, rather than
having two (very similar) versions of this function.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

This does the right thing depending on if we have a session, rather than
needing to handle this manually in multiple places.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

I want to have all callers use this function, rather than calling the
NFS v4.0 and v4.1 versions directly.  This includes pNFS, which only has
access to the nfs_client structure in some places.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

pNFS only has access to the nfs_client structure, and not the
nfs_server, so we need to make this change so the function can be used
by pNFS as well.
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

Some nfsv4.0 servers may return a mode for the verifier following an open
with EXCLUSIVE4 createmode, but this does not mean the client should skip
setting the mode in the following SETATTR.  It should only do that for
EXCLUSIVE4_1 or UNGAURDED createmode.

Fixes: 5334c5bd ("NFS: Send attributes in OPEN request for NFS4_CREATE_EXCLUSIVE4_1")
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Cc: stable@vger.kernel.org # v4.3+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We cannot call nfs4_handle_exception() without first ensuring that the
slot has been freed. If not, we end up deadlocking with the process
waiting for recovery to complete, and recovery waiting for the slot
table to drain.

Fixes: 2e80dbe7 ("NFSv4.1: Close callback races for OPEN, LAYOUTGET...")
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Otherwise, the attribute cache remains marked as being expired.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If the unlink wasn't successful, then the directory has presumably not
changed.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If a file is renamed, but stays in the same directory, we will still receive
2 change_info4 structures describing the change to that directory, but we
only want to apply it once.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We don't want to invalidate the directory attribute and data cache unless we
know that a file was created, or the change attribute differs from the one
in our cache.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

I have reports of a crash that look like __fput() was called twice for
a NFSv4.0 file.  It seems possible that the state manager could try to
reclaim a lock and take a reference on the fl->fl_file at the same time the
file is being released if, during the close(), a signal interrupts the wait
for outstanding IO while removing locks which then skips the removal
of that lock.

Since 83bfff23 ("nfs4: have do_vfs_lock take an inode pointer") has
removed the need to traverse fl->fl_file->f_inode in nfs4_lock_done(),
taking that reference is no longer necessary.
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If our DELEGRETURN RPC call is rejected with an EACCES call, then we should
remove the GETATTR call from the compound RPC and retry.
This could potentially happen when there is a conflict between an
ACL denying attribute reads and our use of SP4_MACH_CRED.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If our CLOSE RPC call is rejected with an EACCES call, then we should
remove the GETATTR call from the compound RPC and retry.
This could potentially happen when there is a conflict between an
ACL denying attribute reads and our use of SP4_MACH_CRED.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

In order to benefit from the DENY share lock protection, we should
put the GETATTR operation before the CLOSE. Otherwise, we might race
with a Windows machine that thinks it is now safe to modify the file.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If we're downgrading from a READ+WRITE mode to a READ-only mode, then
ask for cache consistency attributes so that we avoid the revalidation
in nfs_close_context()

Fixes: 3947b74d ("NFSv4: Don't request a GETATTR on open_downgrade.")
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

DELEGRETURN will always carry a reference to the inode except when
the latter is being freed, so let's ensure that we always use that
inode information to ensure close-to-open cache consistency, even
when the DELEGRETURN call is asynchronous.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If we successfully updated the change attribute, we should timestamp the
cache. While we do know that the other attributes are not completely up
to date, we have the NFS_INO_INVALID_ATTR flag that let us know that,
so it is valid to say that the cache has not timed out.
We can also clear NFS_INO_REVAL_PAGECACHE, since our change attribute
is now known to be valid.

Conversely, if the change attribute did not match, we should make sure to
also revalidate the access and ACL caches.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Clients can set the umask attribute when creating files to cause the
server to apply it always except when inheriting permissions from the
parent directory.  That way, the new files will end up with the same
permissions as files created locally.

See https://tools.ietf.org/html/draft-ietf-nfsv4-umask-02 for more details.
Signed-off-by: NAndreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The layout-private data may depend on the layout and/or the inode
still existing when it does post-processing and frees its data, so we
need to free them after calling lrp->ld_private.ops->free().

This fixes a mirror list corruption issue in the flexfiles driver.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Otherwise the lock context won't be freed when we're done with it.

From: NeilBrown <neilb@suse.com>
Fixes: 5bd3f817 ("NFSv4: change nfs4_select_rw_stateid to take a lock_context inplace of lock_owner")
Signed-off-by: NAnna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

In the case where SEQUENCE receives a NFS4ERR_BADSESSION or
NFS4ERR_DEADSESSION error, we just want to report the session as needing
recovery, and then we want to retry the operation.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Cleanup to allow layout drivers to attach private data to layoutreturn,
and manage the data.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The only time that a lock_context is not immediately available is in
setattr, and now that it has an open_context, it can easily find one
with nfs_get_lock_context.
This removes the need for the on-stack nfs_lockowner.

This change is preparation for correctly support flock stateids.
Signed-off-by: NNeilBrown <neilb@suse.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The open_context can always lead directly to the state, and is always easily
available, so this is a straightforward change.
Doing this makes more information available to _nfs4_do_setattr() for use
in the next patch.
Signed-off-by: NNeilBrown <neilb@suse.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

An open file description (struct file) in a given process can be
associated with two different lock owners.

It can have a Posix lock owner which will be different in each process
that has a fd on the file.
It can have a Flock owner which will be the same in all processes.

When searching for a lock stateid to use, we need to consider both of these
owners

So add a new "flock_owner" to the "nfs_open_context" (of which there
is one for each open file description).

This flock_owner does not need to be reference-counted as there is a
1-1 relation between 'struct file' and nfs open contexts,
and it will never be part of a list of contexts.  So there is no need
for a 'flock_context' - just the owner is enough.

The io_count included in the (Posix) lock_context provides no
guarantee that all read-aheads that could use the state have
completed, so not supporting it for flock locks in not a serious
problem.  Synchronization between flock and read-ahead can be added
later if needed.

When creating an open_context for a non-openning create call, we don't have
a 'struct file' to pass in, so the lock context gets initialized with
a NULL owner, but this will never be used.

The flock_owner is not used at all in this patch, that will come later.
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NNeilBrown <neilb@suse.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

this field is not used in any important way and probably should
have been removed by

Commit: 8003d3c4 ("nfs4: treat lock owners as opaque values")

which removed the pid argument from nfs4_get_lock_state.

Except in unusual and uninteresting cases, two threads with the same
->tgid will have the same ->files pointer, so keeping them both
for comparison brings no benefit.
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NNeilBrown <neilb@suse.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If we cannot grab the inode or superblock, then we cannot pin the
layout header, and so we cannot send a layoutreturn as part of an
async delegreturn call. In this case, we currently end up sending
an extra layoutreturn after the delegreturn. Since the layout was
implicitly returned by the delegreturn, that just gets a BAD_STATEID.

The fix is to simply complete the return-on-close immediately.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Amend the pnfs return on close helper functions to enable sending the
layoutreturn op in CLOSE/DELEGRETURN. This closes a potential race between
CLOSE/DELEGRETURN and parallel OPEN calls to the same file, and allows the
client and the server to agree on whether or not there is an outstanding
layout.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Add XDR encoding for the layoutreturn op, and storage for the layoutreturn
arguments to the DELEGRETURN compound.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Add XDR encoding for the layoutreturn op, and storage for the layoutreturn
arguments to the CLOSE compound.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Fix a potential race with CB_LAYOUTRECALL in which the server recalls the
remaining layout segments while our LAYOUTRETURN is still in transit.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We may want to process and transmit layout stat information for the
layout segments that are being returned, so we should defer freeing
them until after the layoutreturn has completed.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If holding a delegation, we do not need to ask the server to return
close-to-open cache consistency attributes as part of the CLOSE
compound.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We don't need to ask for the change attribute when returning a delegation
or recovering from a server reboot, and it could actually cause us to
obtain an incorrect value if we're using a pNFS flavour that requires
LAYOUTCOMMIT.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If we're reclaiming state after a reboot, or as part of returning a
delegation, we don't need to check access modes again.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

While walking the list of lock_states, keep a reference on each
nfs4_lock_state to be checked, otherwise the lock state could be removed
while the check performs TEST_STATEID and possible FREE_STATEID.
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>