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

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

Move call to get the lease time and the setup of the state
renewal out of nfs4_create_session so that it can be called
after clearing the DRAINING flag.  We use the getattr RPC
to obtain the lease time, which requires a sequence slot.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

We should not assume that nfs41_init_clientid() will always want to
initialise the session. If it is being called due to a server reboot, then
we just want to reset the session after re-establishing the clientid.

Fix this by getting rid of the 'reset' parameter in
nfs4_proc_create_session(), and instead relying on whether or not the
session slot table pointer is non-NULL.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Implements RECLAIM_COMPLETE as an asynchronous RPC.
NFS4ERR_DELAY is retried, NFS4ERR_DEADSESSION invokes the error handling
but does not result in a retry, since we don't want to have a lingering
RECLAIM_COMPLETE call sent in the middle of a possible new state recovery
cycle.  If a session reset occurs, a new wave of reclaim operations will
follow, containing their own RECLAIM_COMPLETE call.  We don't want a
retry to get on the way of recovery by incorrectly indicating to the
server that we're done reclaiming state.

A subsequent patch invokes the functionality.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

the server can indicate a number of error conditions by setting the
appropriate bits in the SEQUENCE operation. The client re-establishes
state with the server when it receives one of those, with the action
depending on the specific case.
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

The NFSv4.1 spec-29 (18.36.3) says that the server MUST use an ONC RPC
(program) version number equal to 4 in callbacks sent to the client.
For now we allow both versions 1 and 4.
Signed-off-by: Alexandros Batsakis <batsakis@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

If the session is reset during state recovery, the state manager thread can
sleep on the slot_tbl_waitq causing a deadlock.

Add a completion framework to the session.  Have the state manager thread set
a new session state (NFS4CLNT_SESSION_DRAINING) and wait for the session slot
table to drain.

Signal the state manager thread in nfs41_sequence_free_slot when the
NFS4CLNT_SESSION_DRAINING bit is set and the session is drained.
Reported-by: Trond Myklebust <trond@netapp.com>
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

The bit is no longer used for session setup, only for session reset.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Reported-by: Trond Myklebust <trond.myklebust@netapp.com>

Resetting the clientid from the state manager could result in not confirming
the clientid due to create session not being called.

Move the create session call from the NFS4CLNT_SESSION_SETUP state manager
initialize session case into the NFS4CLNT_LEASE_EXPIRED case establish_clid
call.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Commit 008f55d0

 (nfs41: recover lease in
_nfs4_lookup_root) forces the state manager to always run on mount. This is
a bug in the case of NFSv4.0, which doesn't require us to send a
setclientid until we want to grab file state.

In any case, this is completely the wrong place to be doing state
management. Moving that code into nfs4_init_session...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Unlike SETCLIENTID, EXCHANGE_ID requires a machine credential. Do not search
for credentials other than the machine credential.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

EXCHANGE_ID has different credential requirements than SETCLIENTID.
Prepare for a separate credential function.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfsv4.1 clientid is established via EXCHANGE_ID rather than
SETCLIENTID{,_CONFIRM}

This is implemented using a new establish_clid method in
nfs4_state_recovery_ops.

nfs41: establish clientid via exchange id only if cred != NULL

>From 2.6.26 reclaimer() uses machine cred for setting up the client id
therefore it is never expected to be NULL.
Signed-off-by: Rahul Iyer <iyer@netapp.com>
[removed dprintk]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: lease renewal]
[revamped patch for new nfs4_state_manager design]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Use the machine cred for sending SEQUENCE to renew
the client's lease.

[revamp patch for new state management design starting 2.6.29]
[nfs41: support minorversion 1 for nfs4_check_lease]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: get cred in exchange_id when cred arg is NULL]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: use cl_machined_cred instead of cl_ex_cred]
    Since EXCHANGE_ID insists on using the machine credential, cl_ex_cred is
    not needed. nfs4_proc_exchange_id() is only called if the machine credential
    is available. Remove the credential logic from nfs4_proc_exchange_id.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

[moved nfs4_get_renew_cred related changes to
 "nfs41: introduce get_state_renewal_cred"]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Send a NFSv4.1 SEQUENCE op rather than RENEW that was deprecated in
minorversion 1.
Use the nfs_client minorversion to select reboot_recover/
network_partition_recovery/state_renewal ops.

Note: we use reclaimer to create the nfs41 session before there are any
cl_superblocks for the nfs_client.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: check for session not minorversion]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[revamped patch for new nfs4_state_manager design]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: obliterate nfs4_state_recovery_ops.renew_lease method]
    moved to nfs4_state_maintenance_ops
[also undid per-minorversion nfs4_state_recovery_ops here]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Move the code to reset a session from the session_reclaimer to the
nfs4_state_manager.  Destroy the session, and create a new one. Treat
NFS4ERR_BADSESSION and NFS4ERR_DEADSESSION as a successful
nfs4_proc_destroy_session. Signal nfs4_proc_create_session that this is a
session reset so that the session slot table is re-used.

If the clientid is stale, set both NFS4CLNT_LEASE_EXPIRED and
NFS4CLNT_SESSION_SETUP bits and retry.

Use a switch statement in nfs4_session_recovery_handle_error for future
patche which will add handling for other errors.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>

[nfs41: session reset in nfs4_recovery_handle_error]
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: reset session on nfs4_do_reclaim session reset error]
    If nfs4_do_reclaim gets a session reset error, nfs4_recovery_handle_error
    will set the NFS4CLNT_SESSION_SETUP bit, and the state manager should
    continue processing to reset the session.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[move nfs4_proc_destroy_session declaration here]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

At mount, nfs_alloc_client sets the cl_state NFS4CLNT_LEASE_EXPIRED bit
and nfs4_alloc_session sets the NFS4CLNT_SESSION_SETUP bit, so both bits are
set when nfs4_lookup_root calls nfs4_recover_expired_lease which schedules
the nfs4_state_manager and waits for it to complete.

Place the session setup after the clientid establishment in nfs4_state_manager
so that the session is setup right after the clientid has been established
without rescheduling the state manager.

Unlike nfsv4.0, the nfs_client struct is not ready to use until the session
has been established.  Postpone marking the nfs_client struct to NFS_CS_READY
until after a successful CREATE_SESSION call so that other threads cannot use
the client until the session is established.

If the EXCHANGE_ID call fails and the session has not been setup (the
NFS4CLNT_SESSION_SETUP bit is set), mark the client with the error and return.

If the session setup CREATE_SESSION call fails with NFS4ERR_STALE_CLIENTID
which could occur due to server reboot or network partition inbetween the
EXCHANGE_ID and CREATE_SESSION call, reset the NFS4CLNT_LEASE_EXPIRED and
NFS4CLNT_SESSION_SETUP bits and try again.

If the CREATE_SESSION call fails with other errors, mark the client with
the error and return.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>

[nfs41: NFS_CS_SESSION_SETUP cl_cons_state for back channel setup]
  On session setup, the CREATE_SESSION reply races with the server back channel
  probe which needs to succeed to setup the back channel. Set a new
  cl_cons_state NFS_CS_SESSION_SETUP just prior to the CREATE_SESSION call
  and add it as a valid state to nfs_find_client so that the client back channel
  can find the nfs_client struct and won't drop the server backchannel probe.
  Use a new cl_cons_state so that NFSv4.0 back channel behaviour which only
  sets NFS_CS_READY is unchanged.
  Adjust waiting on the nfs_client_active_wq accordingly.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>

[nfs41: rename NFS_CS_SESSION_SETUP to NFS_CS_SESSION_INITING]
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: set NFS_CL_SESSION_INITING in alloc_session]
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: move session setup into a function]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[moved nfs4_proc_create_session declaration here]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Allocate a slot in the session slot table and set the sequence op arguments.

Called at the rpc prepare stage.

Add a status to nfs41_sequence_res, initialize it to one so that we catch
rpc level failures which do not go through decode_sequence which sets
the new status field.

Note that upon an rpc level failure, we don't know if the server processed the
sequence operation or not. Proceed as if the server did process the sequence
operation.
Signed-off-by: Rahul Iyer <iyer@netapp.com>
[nfs41: sequence args use slotid]
[nfs41: find slot return slotid]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: remove SEQ4_STATUS_USE_TK_STATUS]
As per 11-14-08 review
[move extern declaration from nfs41: sequence setup/done support]
[removed sa_session definition, changed sa_cache_this into a u8 to reduce footprint]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: rpc_sleep_on slot_tbl_waitq must be called under slot_tbl_lock]
    Otherwise there's a race (we've hit) with nfs4_free_slot where
    nfs41_setup_sequence sees a full slot table, unlocks slot_tbl_lock,
    nfs4_free_slots happen concurrently and call rpc_wake_up_next
    where there's nobody to wake up yet, context goes back to
    nfs41_setup_sequence which goes to sleep when the slot table
    is actually empty now and there's no-one to wake it up anymore.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4.1 Sessions basic data types, initialization, and destruction.

The session is always associated with a struct nfs_client that holds
the exchange_id results.
Signed-off-by: Rahul Iyer <iyer@netapp.com>
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[remove extraneous rpc_clnt pointer, use the struct nfs_client cl_rpcclient.
remove the rpc_clnt parameter from nfs4 nfs4_init_session]
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[Use the presence of a session to determine behaviour instead of the
minorversion number.]
Signed-off-by: Andy Adamson <andros@netapp.com>
[constified nfs4_has_session's struct nfs_client parameter]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[Rename nfs4_put_session() to nfs4_destroy_session() and call it from nfs4_free_client() not nfs4_free_server().
Also get rid of nfs4_get_session() and the ref_count in nfs4_session struct as keeping track of nfs_client should be sufficient]
Signed-off-by: Alexandros Batsakis <Alexandros.Batsakis@netapp.com>
[nfs41: pass rsize and wsize into nfs4_init_session]
Signed-off-by: Andy Adamson <andros@netapp.com>
[separated out removal of rpc_clnt parameter from nfs4_init_session ot a
 patch of its own]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[Pass the nfs_client pointer into nfs4_alloc_session]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: don't assign to session->clp->cl_session in nfs4_destroy_session]
[nfs41: fixup nfs4_clear_client_minor_version]
[introduce nfs4_clear_client_minor_version() in this patch]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[Refactor nfs4_init_session]
    Moved session allocation into nfs4_init_client_minor_version, called from
    nfs4_init_client.
    Leave rwise and wsize initialization in nfs4_init_session, called from
    nfs4_init_server.
    Reverted moving of nfs_fsid definition to nfs_fs_sb.h
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: Move NFS4_MAX_SLOT_TABLE define from under CONFIG_NFS_V4_1]
[Fix comile error when CONFIG_NFS_V4_1 is not set.]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[moved nfs4_init_slot_table definition to "create_session operation"]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: alloc session with GFP_KERNEL]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

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

nfs4_map_errors() can become static.
Signed-off-by: WANG Cong <wangcong@zeuux.org>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

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

Let the actual delegreturn stuff be run in the state manager thread rather
than allocating a separate kthread.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

It is really a more general purpose state management thread at this point.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Add a delegation cleanup phase to the state management loop, and do the
NFS4ERR_CB_PATH_DOWN recovery there.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFSv4 defines a number of state errors which the client does not currently
handle. Among those we should worry about are:
  NFS4ERR_ADMIN_REVOKED - the server's administrator revoked our locks
  			  and/or delegations.
  NFS4ERR_BAD_STATEID - the client and server are out of sync, possibly
                        due to a delegation return racing with an OPEN
			request.
  NFS4ERR_OPENMODE - the client attempted to do something not sanctioned
  		     by the open mode of the stateid. Should normally just
		     occur as a result of a delegation return race.
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>

If the client for some reason is not able to recover all its state within
the time allotted for the grace period, and the server reboots again, the
client is not allowed to recover the state that was 'lost' using reboot
recovery.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Ditto for nfs4_get_setclientid_cred().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

nfs4_drop_state_owner() can now become static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

Sharing the open sequence queue causes a deadlock when we try to take
both a lock sequence id and and open sequence id.

This fixes the regression reported by Dimitri Puzin and Jeff Garzik: See

	http://bugzilla.kernel.org/show_bug.cgi?id=9712



for details.
Reported-and-tested-by: Dimitri Puzin <bugs@psycast.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Olof Johansson <olof@lixom.net>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Otherwise, we do end up breaking close-to-open semantics. We also end up
breaking some of the silly-rename tests in Connectathon on some setups.

Please refer to the bug-report at
	http://bugzilla.linux-nfs.org/show_bug.cgi?id=150

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

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

Consider the case where the user has mounted the remote filesystem
server:/foo on the two local directories /bar and /baz using the
nosharedcache mount option. The files /bar/file and /baz/file are
represented by different inodes in the local namespace, but refer to the
same file /foo/file on the server.
Consider the case where a process opens both /bar/file and /baz/file, then
closes /bar/file: because the nfs4_state is not shared between /bar/file
and /baz/file, the kernel will see that the nfs4_state for /bar/file is no
longer referenced, so it will send off a CLOSE rpc call. Unless the
open_owners differ, then that CLOSE call will invalidate the open state on
/baz/file too.

Conclusion: we cannot share open state owners between two different
non-shared mount instances of the same filesystem.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

We really don't need to grab both the state->so_owner and the
inode->i_lock.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>