These inode operations are no longer used; remove them.
Signed-off-by: NAndreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Ensure that we conform to the algorithm described in RFC5661, section
18.36.4 for when to bump the sequence id. In essence we do it for all
cases except when the RPC call timed out, or in case of the server returning
NFS4ERR_DELAY or NFS4ERR_STALE_CLIENTID.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org

If the server fails to set lrp->res.lrs_present in the LAYOUTRETURN reply,
then that means it believes the client holds no more layout state for that
file, and that the layout stateid is now invalid.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Defer freeing the slot until after we have processed the results from
OPEN and LAYOUTGET. This means that the server can rely on the
mechanism in RFC5661 Section 2.10.6.3 to ensure that replies to an
OPEN or LAYOUTGET/RETURN RPC call don't race with the callbacks that
apply to them.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

For operations like OPEN or LAYOUTGET, which return recallable state
(i.e. delegations and layouts) we want to enable the mechanism for
resolving recall races in RFC5661 Section 2.10.6.3.
To do so, we will want to defer bumping the slot's sequence number until
we have finished processing the RPC results.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If CB_SEQUENCE tells us that the processing of this request depends on
the completion of one or more referring triples (see RFC 5661 Section
2.10.6.3), delay the callback processing until after the RPC requests
being referred to have completed.
If we end up delaying for more than 1/2 second, then fall back to
returning NFS4ERR_DELAY in reply to the callback.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Make a helper function nfs4_set_lease_period() and have
nfs41_setup_state_renewal() and nfs4_do_fsinfo() use it.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Use the minor version ops cached in struct nfs_client instead of looking
them up again.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Make it static
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

That's already being taken care of in pnfs_layout_remove_lseg().
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Ensure nfs42_layoutstat_done() layoutget don't open code layout stateid
invalidation.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If the layout was completely returned, then ignore the returned layout
stateid.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

We want to recover the open stateid if there is no layout stateid
and/or the stateid argument matches an open stateid.
Otherwise throw out the existing layout and recover from scratch, as
the layout stateid is bad.

Fixes: 183d9e7b ("pnfs: rework LAYOUTGET retry handling")
Cc: stable@vger.kernel.org # 4.7
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>

They are not the same error, and need to be handled differently.

Fixes: 183d9e7b ("pnfs: rework LAYOUTGET retry handling")
Cc: stable@vger.kernel.org # 4.7
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>

Fix up nfs4_do_handle_exception() so that it can check if the operation
that received the NFS4ERR_BAD_STATEID was using a defunct delegation.
Apply that to the case of SETATTR, which will currently return EIO
in some cases where this happens.
Reported-by: NOlga Kornievskaia <kolga@netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If a pNFS client sets hdr->pgio_done_cb, then we should not overwrite that
in nfs4_proc_read_setup()

Fixes: 75bf47eb ("pNFS/flexfile: Fix erroneous fall back to...")
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Olga Kornievskaia reports that the following test fails to trigger
an OPEN_DOWNGRADE on the wire, and only triggers the final CLOSE.

	fd0 = open(foo, RDRW)   -- should be open on the wire for "both"
	fd1 = open(foo, RDONLY)  -- should be open on the wire for "read"
	close(fd0) -- should trigger an open_downgrade
	read(fd1)
	close(fd1)

The issue is that we're missing a check for whether or not the current
state transitioned from an O_RDWR state as opposed to having transitioned
from a combination of O_RDONLY and O_WRONLY.
Reported-by: NOlga Kornievskaia <aglo@umich.edu>
Fixes: cd9288ff ("NFSv4: Fix another bug in the close/open_downgrade code")
Cc: stable@vger.kernel.org # 2.6.33+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

We must call nfs4_handle_exception() on BAD_STATEID errors. The only
exception is if the stateid argument turns out to be a layout stateid
that is declared invalid.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: NJeff Layton <jlayton@poochiereds.net>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

nfs4_handle_exception() relies on the caller setting the 'inode' field
in the struct nfs4_exception argument when the error applies to a
delegation.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: NJeff Layton <jlayton@poochiereds.net>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

preparation for similar switch in ->setxattr() (see the next commit for
rationale).
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

There are several problems in the way a stateid is selected for a
LAYOUTGET operation:

We pick a stateid to use in the RPC prepare op, but that makes
it difficult to serialize LAYOUTGETs that use the open stateid. That
serialization is done in pnfs_update_layout, which occurs well before
the rpc_prepare operation.

Between those two events, the i_lock is dropped and reacquired.
pnfs_update_layout can find that the list has lsegs in it and not do any
serialization, but then later pnfs_choose_layoutget_stateid ends up
choosing the open stateid.

This patch changes the client to select the stateid to use in the
LAYOUTGET earlier, when we're searching for a usable layout segment.
This way we can do it all while holding the i_lock the first time, and
ensure that we serialize any LAYOUTGET call that uses a non-layout
stateid.

This also means a rework of how LAYOUTGET replies are handled, as we
must now get the latest stateid if we want to retransmit in response
to a retryable error.

Most of those errors boil down to the fact that the layout state has
changed in some fashion. Thus, what we really want to do is to re-search
for a layout when it fails with a retryable error, so that we can avoid
reissuing the RPC at all if possible.

While the LAYOUTGET RPC is async, the initiating thread always waits for
it to complete, so it's effectively synchronous anyway. Currently, when
we need to retry a LAYOUTGET because of an error, we drive that retry
via the rpc state machine.

This means that once the call has been submitted, it runs until it
completes. So, we must move the error handling for this RPC out of the
rpc_call_done operation and into the caller.

In order to handle errors like NFS4ERR_DELAY properly, we must also
pass a pointer to the sliding timeout, which is now moved to the stack
in pnfs_update_layout.

The complicating errors are -NFS4ERR_RECALLCONFLICT and
-NFS4ERR_LAYOUTTRYLATER, as those involve a timeout after which we give
up and return NULL back to the caller. So, there is some special
handling for those errors to ensure that the layers driving the retries
can handle that appropriately.
Signed-off-by: NJeff Layton <jeff.layton@primarydata.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

LAYOUTRETURN is "special" in that servers and clients are expected to
work with old stateids. When the client sends a LAYOUTRETURN with an old
stateid in it then the server is expected to only tear down layout
segments that were present when that seqid was current. Ensure that the
client handles its accounting accordingly.
Signed-off-by: NJeff Layton <jeff.layton@primarydata.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

When we're using a delegation to represent our open state, we should
ensure that we use the stateid that was used to create that delegation.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

In order to more easily distinguish what kind of stateid we are dealing
with, introduce a type that can be used to label the stateid structure.

The label will be useful both for debugging, but also when dealing with
operations like SETATTR, READ and WRITE that can take several different
types of stateid as arguments.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

RPC-over-RDMA transports have a limit on how large a backward
direction (backchannel) RPC message can be. Ensure that the NFSv4.x
CREATE_SESSION operation advertises this limit to servers.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Tested-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

OPEN_CREATE with EXCLUSIVE4_1 sends initial file permission.
Ignoring  fact, that server have indicated that file mod is set, client
will send yet another SETATTR request, but, as mode is already set,
new SETATTR will be empty. This is not a problem, nevertheless
an extra roundtrip and slow open on high latency networks.

This change is aims to skip extra setattr after open  if there are
no attributes to be set.
Signed-off-by: NTigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

This adds the copy_range file_ops function pointer used by the
sys_copy_range() function call.  This patch only implements sync copies,
so if an async copy happens we decode the stateid and ignore it.
Signed-off-by: NAnna Schumaker <bjschuma@netapp.com>

use d_alloc_parallel() for sillyunlink/lookup exclusion and
explicit rwsem (nfs_rmdir() being a writer and nfs_call_unlink() -
a reader) for rmdir/sillyunlink one.

That ought to make lookup/readdir/!O_CREAT atomic_open really
parallel on NFS.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

At Connectathon 2016, we found that recent upstream Linux clients
would occasionally send a LOCK operation with a zero stateid. This
appeared to happen in close proximity to another thread returning
a delegation before unlinking the same file while it remained open.

Earlier, the client received a write delegation on this file and
returned the open stateid. Now, as it is getting ready to unlink the
file, it returns the write delegation. But there is still an open
file descriptor on that file, so the client must OPEN the file
again before it returns the delegation.

Since commit 24311f88 ('NFSv4: Recovery of recalled read
delegations is broken'), nfs_open_delegation_recall() clears the
NFS_DELEGATED_STATE flag _before_ it sends the OPEN. This allows a
racing LOCK on the same inode to be put on the wire before the OPEN
operation has returned a valid open stateid.

To eliminate this race, serialize delegation return with the
acquisition of a file lock on the same file. Adopt the same approach
as is used in the unlock path.

This patch also eliminates a similar race seen when sending a LOCK
operation at the same time as returning a delegation on the same file.

Fixes: 24311f88 ('NFSv4: Recovery of recalled read ... ')
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
[Anna: Add sentence about LOCK / delegation race]
Signed-off-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>

... and do not assume they are already attached to each other
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

new primitive: d_exact_alias(dentry, inode).  If there is an unhashed
dentry with the same name/parent and given inode, rehash, grab and
return it.  Otherwise, return NULL.  The only caller of d_add_unique()
switched to d_exact_alias() + d_splice_alias().
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

In the case where d_add_unique() finds an appropriate alias to use it will
have already incremented the reference count.  An additional dget() to swap
the open context's dentry is unnecessary and will leak a reference.
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Fixes: 275bb307 ("NFSv4: Move dentry instantiation into the NFSv4-...")
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Fix oops when NULL callback_ops pointer accessed in rpc_init_task
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Use the new helper to ensure that nfs4_proc_bind_conn_to_session() is called
for all connections.
However ensure that we only set the backchannel flag for the connection
pointed to by rpc_clnt->cl_xprt.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Instead, use the values encoded in the slot table itself.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

This ensures that we don't reuse the stateid if a layout return or
implied layout return means that we've returned all layout segments
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If we're unable to perform the layoutget due to an invalid open stateid
or a bulk recall, ensure that we return the error so that the caller
can decide on an appropriate action.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Instead of mapping it to EIO that is a fatal error and
fails application. We'll go inband after getting
NFS4ERR_LAYOUTUNAVAILABLE.
Signed-off-by: NPeng Tao <tao.peng@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Since commit 2d8ae84f, nothing is bumping lo->plh_block_lgets in the
layoutreturn path, so it should not be touched in nfs4_layoutreturn_release
either.

Fixes: 2d8ae84f ("NFSv4.1/pnfs: Remove redundant lo->plh_block_lgets...")
Cc: stable@vger.kernel.org # 4.3+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>