If the renewd send queue gets backlogged (e.g., if the server goes down),
we will keep filling the queue with periodic RENEW/SEQUENCE requests.

This patch schedules a new renewd request if and only if the previous one
returns (either success or failure)
Signed-off-by: NAlexandros Batsakis <batsakis@netapp.com>
[Trond.Myklebust@netapp.com: moved nfs4_schedule_state_renewal() into
separate nfs4_renew_release() and nfs41_sequence_release() callbacks
to ensure correct behaviour on call setup failure]
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

renewd should be synchronously killed before we destroy the session in
nfs4_clear_minor_version
Signed-off-by: NAlexandros Batsakis <batsakis@netapp.com>
[Trond.Myklebust@netapp.com: clean up to remove 'unused function
warning when !CONFIG_NFS_V4]
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

For NFSv2 and v3:

O_DIRECT writes are always synchronous, and aren't cached, so nothing
should be flushed when closing an NFS O_DIRECT file descriptor.  Thus
there are no write errors to report on close(2).

In addition, there's no cached data to verify on the next open(2),
so we don't need clean GETATTR results at close time to compare with.

Thus, there's no need for the nfs_revalidate_inode() call when closing
an NFS O_DIRECT file.  This reduces the number of synchronous
on-the-wire requests for a simple open-write-close of an NFS O_DIRECT
file by roughly 20%.

For NFSv4:

Call nfs4_do_close() with wait set to zero when closing an NFS
O_DIRECT file.  The CLOSE will go on the wire, but the application
won't wait for it to complete.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The bytes counted by the performance counters for NFS writes should
reflect write and sync errors.  If the write(2) system call reports
an error, the bytes should not be counted.  And, if the write is
short, the actual number of bytes that was written should be counted,
not the number of bytes that was requested.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Bytes read via the splice API should be accounted for in the NFS
performance statistics.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Currently, the NFS I/O counters count the number of bytes requested
by applications, rather than the number of bytes actually read by the
system calls.

The number of bytes requested for reads is actually not that useful,
because the value is usually a buffer size for reads.  That is, that
requested number is usually a maximum, and frequently doesn't reflect
the actual number of bytes read.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Nit: The VFSOPEN and VFSFLUSH counters are function call counters.
Count every call to these routines.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

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

Return NFS4_OK if target high slotid equals enforced high slotid.
Fix nfs_client reference leak.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

When session is reset, client can renegotiate slot table size.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Drain the fore channel and reset the max_slots to the new value.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

For now the back channel ca_maxresponsesize_cached is 0 and there is no
backchannel DRC. Return NFS4ERR_REP_TOO_BIG_TO_CACHE when a cb_sequence
cachethis is true.  When it is false, return NFS4ERR_RETRY_UNCACHED_REP as the
next operation error.

Remember the replay error accross compound operation processing.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Make all cb_sequence arguments available to verify_seqid which will make
replay decisions.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

All callback operations have arguments to decode and require processing.
The preprocess_nfs4X_op functions catch unsupported or illegal ops so
decode_args and process_op pointers are always non NULL.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Skip all other processing when error is encountered.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Set NFS4ERR_RESOURCE as CB_COMPOUND status and do not return an op on
decode_op_hdr or encode_op_hdr buffer overflow.

NFS4ERR_RESOURCE is correct for v4.0. Will fix the return for v4.1 along with
all the other NFS4ERR_RESOURCE errors in a later patch.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If a CB_SEQUENCE referring call triple matches a slot table entry, the
client is still waiting for a response to the original request.  In this
case, return NFS4ERR_DELAY as the response to the callback.
Signed-off-by: NMike Sager <sager@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Traverse a list of referring calls and look for a session/slot/seq number
match.
Signed-off-by: NMike Sager <sager@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

For the CREATE_SESSION attribute ca_maxresponsesize_cached, calculate
the value based on the rpc reply header size plus the maximum nfs compound
reply size.
Signed-off-by: NMike Sager <sager@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add a wrapper around rpc_call_sync that handles -EKEYEXPIRED errors from
the RPC layer as it would an -EJUKEBOX error if NFSv2 had such a thing.
Also, add a handler for that error for async calls that makes it
resubmit the RPC on -EKEYEXPIRED.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We're using -EKEYEXPIRED to indicate that a krb5 credcache contains an
expired ticket and that we should have the NFS layer retry the RPC call
instead of returning an error back to the caller. Handle this as we
would an -EJUKEBOX error return.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If a KRB5 TGT ticket expires, we don't want to return an error
immediatel. If someone has a long running job and just forgets to run
"kinit" in time then this will make it fail.

Instead, we want to treat this situation as we would NFS4ERR_DELAY and
retry the upcall after delaying a bit with an exponential backoff.

This patch just makes any place that would handle NFS4ERR_DELAY also
handle -EKEYEXPIRED the same way. In the future, we may want to be more
sophisticated however and handle hard vs. soft mounts differently, or
specify some upper limit on how long we'll wait for a new TGT to be
acquired.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If the NFS_ATTR_FATTR_TYPE field isn't set in fattr->valid, then we should
not set the S_IFMT part of inode->i_mode.
Reported-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Ensure that we unregister the bdi before kill_anon_super() calls
ida_remove() on our device name.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

The VM/VFS does not allow mapping->a_ops->invalidatepage() to fail.
Unfortunately, nfs_wb_page_cancel() may fail if a fatal signal occurs.
Since the NFS code assumes that the page stays mapped for as long as the
writeback is active, we can end up Oopsing (among other things).

The only safe fix here is to convert nfs_wait_on_request(), so as to make
it uninterruptible (as is already the case with wait_on_page_writeback()).
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

Even if the server is crazy, we should be able to mark the stateid as being
bad, to ensure it gets recovered.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Reviewed-by: NChuck Lever <chuck.lever@oracle.com>

Currently, nfs4_handle_exception() will call it twice if called with an
error of -NFS4ERR_STALE_CLIENTID, -NFS4ERR_STALE_STATEID or
-NFS4ERR_EXPIRED.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Reviewed-by: NChuck Lever <chuck.lever@oracle.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
Reviewed-by: NChuck Lever <chuck.lever@oracle.com>

In most cases, we just want to mark the lock_stateid sequence id as being
uninitialised.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
Reviewed-by: NChuck Lever <chuck.lever@oracle.com>

Avoid the following warnings when CONFIG_NFS_V4=n:

	fs/nfs/sysctl.c:19: warning: unused variable `nfs_set_port_max'
	fs/nfs/sysctl.c:18: warning: unused variable `nfs_set_port_min'

by making those variables contingent on NFSv4 being configured.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Reviewed-by: NChuck Lever <chuck.lever@oracle.com>

The symbol nfs_commitdata_release is only used locally
in this file. Make it static to prevent the following sparse warning:

warning: symbol 'nfs_commitdata_release' was not declared. Should it be static?
Signed-off-by: NH Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Reviewed-by: NChuck Lever <chuck.lever@oracle.com>

If someone calls nfs_release_page(), we presumably already know that the
page is clean, however it may be holding an unstable write.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
Reviewed-by: NChuck Lever <chuck.lever@oracle.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
Reviewed-by: NChuck Lever <chuck.lever@oracle.com>

Recent change is missing to update "rehash".  With that change, it will
become the cause of adding dentry to hash twice.

This explains the reason of Oops (dereference the freed dentry in
__d_lookup()) on my machine.
Signed-off-by: NOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Reported-by: NMarvin <marvin24@gmx.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This reverts commit e9496ff4. Quoth Al:

 "it's dependent on a lot of other stuff not currently in mainline
  and badly broken with current fs/namespace.c.  Sorry, badly
  out-of-order cherry-pick from old queue.

  PS: there's a large pending series reworking the refcounting and
  lifetime rules for vfsmounts that will, among other things, allow to
  rip a subtree away _without_ dissolving connections in it, to be
  garbage-collected when all active references are gone.  It's
  considerably saner wrt "is the subtree busy" logics, but it's nowhere
  near being ready for merge at the moment; this changeset is one of the
  things becoming possible with that sucker, but it certainly shouldn't
  have been picked during this cycle.  My apologies..."
Noticed-by: NEric Paris <eparis@redhat.com>
Requested-by: NAl Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

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

Commit 5601a00d (nfs: run state manager
in privileged mode) introduces a regression in the NFSv4 code when
compiled with CONFIG_NFS_V4_1. The calls to nfs4_end_drain_session()
from the main loop in nfs4_state_manager() Oops due to the lack of an
NFSv4.1 session when running NFSv4.0.

The fix is to move those two calls back into nfs41_init_clientid() and
nfs4_reset_session().

The calls to nfs4_end_drain_session() that remain inside
nfs4_state_manager() are safe, since the NFSv4.0 code will never set the
NFS4CLNT_SESSION_DRAINING bit.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If the CLOSE or OPEN_DOWNGRADE call triggers a state recovery, and has
to be resent, then we must release the seqid. Otherwise the open
recovery will wait for the close to finish, which causes a deadlock.

This is mainly a NFSv4.1 problem, although it can theoretically happen
with NFSv4.0 too, in a OPEN_DOWNGRADE situation.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If the rsize or wsize is not set on the mount command, negotiate the highest
supported rsize and wsize in session creation.

Fixes a bug where the client negotiated nfs41_maxwrite_overhead as
ca_maxrequestsize and nfs41_maxread_overhead as ca_maxresponsesize resulting
in NFS4ERR_REQ_TOO_BIG errors on writes.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>