Defines a new 'struct nfs4_slot_table' in the 'struct nfs4_session'
for use by the backchannel. Initializes, resets, and destroys the backchannel
slot table in the same manner the forechannel slot table is initialized,
reset, and destroyed.
The sequenceid for each slot in the backchannel slot table is initialized
to 0, whereas the forechannel slotid's sequenceid is set to 1.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Generalize nfs4_init_slot_table() so it can be used to initialize the
backchannel slot table in addition to the forechannel slot table.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Generalize nfs4_reset_slot_table() so it can be used to reset the
backchannel slot table in addition to the forechannel slot table.
Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Frees the preallocated backchannel resources that are associated with
this session when the session is destroyed.
A backchannel is currently created once per session. Destroy the backchannel
only when the session is destroyed.
Signed-off-by: Ricardo Labiaga <ricardo.labiaga@netapp.com>
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Set the SESSION4_BACK_CHAN flag to indicate the client supports a backchannel.
Signed-off-by: Ricardo Labiaga <ricardo.labiaga@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
It is possible for servers to return NFS4ERR_BAD_STATEID when
the state management code is recovering locks or is reclaiming state when
returning a delegation. Ensure that we handle that case.
While we're at it, add in handlers for NFS4ERR_STALE,
NFS4ERR_ADMIN_REVOKED, NFS4ERR_OPENMODE, NFS4ERR_DENIED and
NFS4ERR_STALE_STATEID, since the protocol appears to allow for them too.
Also handle ENOMEM...
Finally, rather than add new NFSv4.0-specific errors and error handling into
the generic delegation code, move that open file and locking state error
handling into the NFSv4 layer.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The NFSv4 delegation recovery code is required by the protocol to handle
more errors. Rather than add NFSv4.0 specific errors into 'generic'
delegation code, we should move the error handling into the NFSv4 layer.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Unlike minorversion0, in nfsv4.1 the open and lock seqids need
not be incremented by the client and should always be set to zero.
This is implemented using a new nfs_rpc_ops methods -
increment_open_seqid and increment_lock_seqid
Signed-off-by: Rahul Iyer <iyer@netapp.com>
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>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This creates the nfsv4.1 session on mount.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
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>
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>
Define a new session reset state which is set upon a sequence operation error
in both the sync and async error handlers.
Place all new requests and all but the last outstanding rpc on the
slot_tbl_waitq. Spawn the recovery thread when the last slot is free.
Call nfs4_proc_destroy_session, reinitialize the session, call
nfs4_proc_create_session, clear the session reset state, and wake up the next
task on the slot_tbl_waitq.
Return the nfs4_proc_destroy_session status to the session reclaimer and
check for NFS4ERR_BADSESSION and NFS4ERR_DEADSESSION. Other destroy session
errors should be handled in nfs4_proc_destroy_session where the call can
be retried with adjusted arguments.
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
nfs41: make nfs4_wait_bit_killable public]
nfs4_wait_bit_killable to be used by NFSv4.1 session recover logic.
Signed-off-by: Rahul Iyer <iyer@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: have create_session work on nfs_client]
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: trigger the state manager for session reset]
Replace the session reset state with the NFS4CLNT_SESSION_SETUP cl_state.
Place all rpc tasks to sleep on the slot table waitqueue until the slot
table is drained, then schedule state recovery and wait for it to complete.
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: remove nfs41_session_recovery [ch]
Replaced by using the nfs4_state_manager.
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: nfs4_wait_bit_killable only used locally]
[nfs41: keep nfs4_wait_bit_killable static]
[nfs41: keep const nfs_server in nfs4_handle_exception]
[nfs41: remove session parameter from nfs4_find_slot]
Signed-off-by: Andy Adamson <andros@netapp.com
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: resset the session from nfs41_setup_sequence]
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>
Remove checking for any errors that the SEQUENCE operation does not return.
-NFS4ERR_STALE_CLIENTID, NFS4ERR_EXPIRED, NFS4ERR_CB_PATH_DOWN, NFS4ERR_BACK_CHAN_BUSY, NFS4ERR_OP_NOT_IN_SESSION.
SEQUENCE operation error recovery is very primative, we only reset the session.
Remove checking for any errors that are returned by the SEQUENCE operation, but
that resetting the session won't address.
NFS4ERR_RETRY_UNCACHED_REP, NFS4ERR_SEQUENCE_POS,NFS4ERR_TOO_MANY_OPS.
Add error checking for missing SEQUENCE errors that a session reset will
address.
NFS4ERR_BAD_HIGH_SLOT, NFS4ERR_DEADSESSION, NFS4ERR_SEQ_FALSE_RETRY.
A reset of the session is currently our only response to a SEQUENCE operation
error. Don't reset the session on errors where a new session won't help.
Don't reset the session on errors where a new session won't help.
[nfs41: nfs4_async_handle_error update error checking]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: trigger the state manager for session reset]
Replace session state bit with nfs_client state bit. Set the
NFS4CLNT_SESSION_SETUP bit upon a session related error in the sync/async
error handlers.
[nfs41: _nfs4_async_handle_error fix session reset error list]
Sequence operation errors that session reset could help.
NFS4ERR_BADSESSION
NFS4ERR_BADSLOT
NFS4ERR_BAD_HIGH_SLOT
NFS4ERR_DEADSESSION
NFS4ERR_CONN_NOT_BOUND_TO_SESSION
NFS4ERR_SEQ_FALSE_RETRY
NFS4ERR_SEQ_MISORDERED
Sequence operation errors that a session reset would not help
NFS4ERR_BADXDR
NFS4ERR_DELAY
NFS4ERR_REP_TOO_BIG
NFS4ERR_REP_TOO_BIG_TO_CACHE
NFS4ERR_REQ_TOO_BIG
NFS4ERR_RETRY_UNCACHED_REP
NFS4ERR_SEQUENCE_POS
NFS4ERR_TOO_MANY_OPS
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41 nfs4_handle_exception fix session reset error list]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[moved nfs41_sequece_call_done code to nfs41: sequence operation]
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>
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>
Separated from nfs41: schedule async session reset
Do not kfree the session slot table upon session reset, just re-initialize it.
Add a boolean to nfs4_proc_create_session to inidicate if this is a
session reset or a session initialization.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
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>
Implement the sequence operation conforming to
http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-26
Check returned sessionid, slotid and slot sequenceid in decode_sequence.
If the server returns different values for sessionID, slotID or slot sequence
number than what was sent, the server is looney tunes.
Pass the sequence operation status to nfs41_sequence_done in order to
determine when to increment the slot sequence ID.
Free slot is separated from sequence done.
Signed-off-by: Rahul Iyer <iyer@netapp.com>
Signed-off-by: Ricardo Labiaga <ricardo.labiaga@netapp.com>
Signed-off-by: Andy Adamson<andros@umich.edu>
[nfs41: sequence res use slotid]
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: deref slot table in decode_sequence only for minorversion!=0]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: nfs4_call_sync]
[nfs41: remove SEQ4_STATUS_USE_TK_STATUS]
[nfs41: return ESERVERFAULT in decode_sequence]
[no sr_session, no sr_flags]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: use nfs4_call_sync_sequence to renew session lease]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: remove nfs4_call_sync_sequence forward definition]
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: use struct nfs_client for nfs41_proc_async_sequence]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: pass *session in seq_args and seq_res]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41 nfs41_sequence_call_done update error checking]
[nfs41 nfs41_sequence_done update error checking]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: remove switch on error from nfs41_sequence_call_done]
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>
The session is per struct nfs_client, not per nfs_server. Allow the handler
to be called with no nfs_server which simplifies the nfs4_proc_async_sequence session renewal call and will let it be used by pnfs file layout data servers.
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>
Invalidate the session if the server returns invalid fore or back channel
attributes.
Use a KERN_WARNING to report the fatal session estabishment error.
Signed-off-by: Andy Adamson <andros@netapp.com>
[refactor nfs4_verify_channel_attrs]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Implement the create_session operation conforming to
http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-26
Set the real fore channel max operations to preserve server resources.
Note: If the server returns < NFS4_MAX_OPS, the client will very soon
get an NFS4ERR_TOO_MANY_OPS. A later patch will handle this.
Set the max_rqst_sz and max_resp_sz to PAGE_SIZE - we preallocate the buffers.
Set the back channel max_resp_sz_cached to zero to force the client to
always set csa_cachethis to FALSE because the current implementation
of the back channel DRC only supports caching the CB_SEQUENCE operation.
The client back channel server supports one slot, and desires 2 operations
per compound.
Signed-off-by: Ricardo Labiaga <ricardo.labiaga@netapp.com>
Signed-off-by: Andy Adamson<andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: remove extraneous rpc_clnt pointer]
Use the struct nfs_client cl_rpcclient.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: nfs4_init_channel_attrs, just use nfs41_create_session_args]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: use rsize and wsize for session channel attributes]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: set channel max operations]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: set back channel attributes]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: obliterate nfs4_adjust_channel_attrs]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: have create_session work on nfs_client]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: move CONFIG_NFS_V4_1 endif]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: pass *session in seq_args and seq_res]
[moved nfs4_init_slot_table definition here]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: use kcalloc to allocate slot table]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
[nfs41: fix Xcode_create_session's xdr Xcoding pointer type]
[nfs41: refactor decoding of channel attributes]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
get_lease_time uses the FSINFO rpc operation to
get the lease time attribute.
nfs4_get_lease_time() is only called from the state manager on session setup
so don't recover from clientid or sequence level errors.
We do need to recover from NFS4ERR_DELAY or NFS4ERR_GRACE.
Use NFS4_POLL_RETRY_MIN - the Linux server returns NFS4ERR_DELAY when an
upcall is needed to resolve an uncached export referenced by a file handle.
[nfs41: sequence res use slotid]
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: remove extraneous rpc_clnt pointer]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: have get_lease_time work on nfs_client]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: get_lease_time recover from NFS4ERR_DELAY]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: pass *session in seq_args and seq_res]
[define nfs4_get_lease_time_{args,res}]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Implement the exchange_id operation conforming to
http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-26
Unlike NFSv4.0, NFSv4.1 requires machine credentials. RPC_AUTH_GSS machine
credentials will be passed into the kernel at mount time to be available for
the exchange_id operation.
RPC_AUTH_UNIX root mounts can use the UNIX root credential. Store the root
credential in the nfs_client struct.
Without a credential, NFSv4.1 state renewal fails.
[nfs41: establish clientid via exchange id only if cred != NULL]
Signed-off-by: Andy Adamson<andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfsd41: move nfstime4 from under CONFIG_NFS_V4_1]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: do not wait a lease time in exchange id]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: pass *session in seq_args and seq_res]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
[nfs41: Ignoring impid in decode_exchange_id is missing a READ_BUF]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: fix Xcode_exchange_id's xdr Xcoding pointer type]
[nfs41: get rid of unused struct nfs41_exchange_id_res members]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Separate delegreturn calls from nfs41: sequence setup/done support
Implement the delegreturn rpc_call_prepare method for
asynchronuos nfs rpcs, call nfs41_setup_sequence from
respective rpc_call_validate_args methods.
Call nfs4_sequence_done from respective rpc_call_done methods.
Note that we need to pass a pointer to the nfs_server in calls data
for passing on to nfs4_sequence_done.
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[pnfs: client data server write validate and release]
Signed-off-by: Andy Adamson<andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Separate commit calls from nfs41: sequence setup/done support
Implement the commit rpc_call_prepare method for
asynchronuos nfs rpcs, call nfs41_setup_sequence from
respective rpc_call_validate_args methods.
Call nfs4_sequence_done from respective rpc_call_done methods.
Note that we need to pass a pointer to the nfs_server in calls data
for passing on to nfs4_sequence_done.
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[pnfs: client data server write validate and release]
Signed-off-by: Andy Adamson<andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: Support sessions with O_DIRECT.]
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: separate free slot from sequence done]
[nfs41: nfs4_sequence_free_slot use nfs_client for data server]
Signed-off-by: Andy Adamson<andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Separate write calls from nfs41: sequence setup/done support
Implement the write rpc_call_prepare method for
asynchronuos nfs rpcs, call nfs41_setup_sequence from
respective rpc_call_validate_args methods.
Call nfs4_sequence_done from respective rpc_call_done methods.
Note that we need to pass a pointer to the nfs_server in calls data
for passing on to nfs4_sequence_done.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[pnfs: client data server write validate and release]
Signed-off-by: Andy Adamson <andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[move the nfs4_sequence_free_slot call in nfs_readpage_retry from]
[nfs41: separate free slot from sequence done
Signed-off-by: Andy Adamson <andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: Support sessions with O_DIRECT.]
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: nfs4_sequence_free_slot use nfs_client for data server]
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>
Implement the read rpc_call_prepare method for
asynchronuos nfs rpcs, call nfs41_setup_sequence from
respective rpc_call_validate_args methods.
Call nfs4_sequence_done from respective rpc_call_done methods.
Note that we need to pass a pointer to the nfs_server in calls data
for passing on to nfs4_sequence_done.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[pnfs: client data server write validate and release]
Signed-off-by: Andy Adamson <andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[move the nfs4_sequence_free_slot call in nfs_readpage_retry from]
[nfs41: separate free slot from sequence done]
[remove nfs_readargs.nfs_server, use calldata->inode instead]
Signed-off-by: Andy Adamson <andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: Support sessions with O_DIRECT]
Signed-off-by: Dean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: nfs4_sequence_free_slot use nfs_client for data server]
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>
Implement the rpc_call_prepare methods for
asynchronuos nfs rpcs, call nfs41_setup_sequence from
respective rpc_call_validate_args methods.
Call nfs4_sequence_done from respective rpc_call_done methods.
Note that we need to pass a pointer to the nfs_server in calls data
for passing on to nfs4_sequence_done.
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[pnfs: client data server write validate and release]
Signed-off-by: Andy Adamson<andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: separate free slot from sequence done]
[nfs41: sequence res use slotid]
[nfs41: remove SEQ4_STATUS_USE_TK_STATUS]
[nfs41: nfs4_sequence_free_slot use nfs_client for data server]
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>
Separate nfs4_locku calls from nfs41: sequence setup/done support
Call nfs4_sequence_done from respective rpc_call_done methods.
Note that we need to pass a pointer to the nfs_server in calls data
for passing on to nfs4_sequence_done.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[pnfs: client data server write validate and release]
Signed-off-by: Andy Adamson <andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: nfs4_sequence_free_slot use nfs_client for data server]
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>
Separate nfs4_lock calls from nfs41: sequence setup/done support
Call nfs4_sequence_done from respective rpc_call_done methods.
Note that we need to pass a pointer to the nfs_server in calls data
for passing on to nfs4_sequence_done.
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[pnfs: client data server write validate and release]
[use nfs4_sequence_done_free_slot]
Signed-off-by: Andy Adamson<andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Separate nfs4_open calls from nfs41: sequence setup/done support
Call nfs4_sequence_done from respective rpc_call_done methods.
Note that we need to pass a pointer to the nfs_server in calls data
for passing on to nfs4_sequence_done.
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[pnfs: client data server write validate and release]
[use nfs4_sequence_done_free_slot]
Signed-off-by: Andy Adamson<andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Separate nfs4_close calls from nfs41: sequence setup/done support
Call nfs4_sequence_done from respective rpc_call_done methods.
Note that we need to pass a pointer to the nfs_server in calls data
for passing on to nfs4_sequence_done.
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[pnfs: client data server write validate and release]
Signed-off-by: Andy Adamson<andros@umich.edu>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: separate free slot from sequence done]
[nfs41: sequence res use slotid]
[nfs41: remove SEQ4_STATUS_USE_TK_STATUS]
[nfs41: nfs4_sequence_free_slot use nfs_client for data server]
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>
Implement nfs4.1 synchronous rpc_call_done method
that essentially just calls nfs4_sequence_done, that turns
around and calls nfs41_sequence_done for minorversion1 rpcs.
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>
[move adding nfs4_sequence_free_slot from nfs41-separate-free-slot-from-sequence-done]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: nfs41_call_sync_data use nfs_client not nfs_server]
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>
Handle session level errors, update slot sequence id and
sessions bookeeping, free slot.
[nfs41: sequence res use slotid]
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: remove SEQ4_STATUS_USE_TK_STATUS]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: check for session not minorversion]
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: bail out early out of nfs41_sequence_done if !res->sr_session]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[move nfs4_sequence_done from nfs41: nfs41_call_sync_done]
Signed-off-by: Andy Adamson <andros@netapp.com>
[move nfs4_sequence_free_slot from nfs41: separate free slot from sequence done]
Don't free the slot until after all rpc_restart_calls have completed.
Session reset will require more work.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[moved reset sr_slotid to nfs41_sequence_free_slot]
[free slot also on unexpectecd error]
[remove seq_res.sr_session member, use nfs_client's instead]
[ditch seq_res.sr_flags until used]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[look at sr_slotid for bailing out early from nfs41_sequence_done]
[nfs41: rpc_wake_up_next if sessions slot was not consumed.]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: nfs4_sequence_free_slot use nfs_client for data server]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: remove unused error checking in nfs41_sequence_done]
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: remove nfs4_has_session check in nfs41_sequence_done]
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: remove nfs_client pointer check]
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>
[from nfs41: separate free slot from sequence done]
Don't free the slot until after all rpc_restart_calls have completed.
Session reset will require more work.
As noted by Trond, since we're using rpc_wake_up_next rather than
rpc_wake_up() we must always wake up the next task in the queue
either by going through nfs4_free_slot, or just calling
rpc_wake_up_next if no slot is to be freed.
[nfs41: sequence res use slotid]
[nfs41: remove SEQ4_STATUS_USE_TK_STATUS]
[got rid of nfs4_sequence_res.sr_session, use nfs_client.cl_session instead]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: rpc_wake_up_next if sessions slot was not consumed.]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: nfs4_sequence_free_slot use nfs_client for data server]
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>
Free a slot in the slot table.
Mark the slot as free in the bitmap-based allocation table
by clearing a bit corresponding to the slotid.
Update lowest_free_slotid if freed slotid is lower than that.
Update highest_used_slotid. In the case the freed slotid
equals the highest_used_slotid, scan downwards for the next
highest used slotid using the optimized fls* functions.
Finally, wake up thread waiting on slot_tbl_waitq for a free slot
to become available.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: free slot use slotid]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: use find_first_zero_bit for nfs4_find_slot]
While at it, obliterate lowest_free_slotid and fix-up related comments.
As per review comment 21/85.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: use __clear_bit for nfs4_free_slot]
While at it, fix-up function comment.
Part of review comment 22/85.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: use find_last_bit in nfs4_free_slot to determine highest used slot.]
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>
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>
Find a free slot using bitmap-based allocation.
Use the optimized ffz function to find a zero bit
in the bitmap that indicates a free slot, starting
the search from the 'lowest_free_slotid' position.
If found, mark the slot as used in the bitmap, get
the slot's slotid and seqid, and update max_slotid
to be used by the SEQUENCE operation.
Also, update lowest_free_slotid for next search.
If no free slot was found the caller has to wait
for a free slot (outside the scope of this function)
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: find slot return slotid]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[use find_first_zero_bit for nfs4_find_slot as per review comment 21/85.]
[use NFS4_MAX_SLOT_TABLE rather than NFS4_NO_SLOT]
[nfs41: rpc_sleep_on slot_tbl_waitq must be called under slot_tbl_lock]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Perform the nfs4_setup_sequence in the rpc_call_prepare state.
If a session slot is not available, we will rpc_sleep_on the
slot wait queue leaving the tk_action as rpc_call_prepare.
Once we have a session slot, hang on to it even through rpc_restart_calls.
Ensure the nfs41_sequence_res sr_slot pointer is NULL before rpc_run_task is
called as nfs41_setup_sequence will only find a new slot if it is NULL.
A future patch will call free slot after any rpc_restart_calls, and handle the
rpc restart that result from a sequence operation error.
Signed-off-by: Rahul Iyer <iyer@netapp.com>
[nfs41: sequence res use slotid]
Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: simplify nfs4_call_sync]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: nfs4_call_sync]
[nfs41: check for session not minorversion]
[nfs41: remove rpc_message from nfs41_call_sync_args]
[moved NFS4_MAX_SLOT_TABLE logic into nfs41_setup_sequence]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: nfs41_call_sync_data use nfs_client not nfs_server]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: expose nfs4_call_sync_session for lease renewal]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: remove unnecessary return check]
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>
Initialize nfs4_sequence_res sr_slotid to NFS4_MAX_SLOT_TABLE.
[was nfs41: sequence res use slotid]
Signed-off-by: Andy Adamson <andros@netapp.com>
[pulled definition of struct nfs4_sequence_res.sr_slotid to here]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
To be used for getting the rpc's minorversion and for nfs41 xdr
{en,de}coding of the sequence operation.
Reset the seq session ptrs for minorversion=0 rpc calls.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Use nfs4_call_sync rather than rpc_call_sync to provide
for a nfs41 sessions-enabled interface for sessions manipulation.
The nfs41 rpc logic uses the rpc_call_prepare method to
recover and create the session, as well as selecting a free slot id
and the rpc_call_done to free the slot and update slot table
related metadata.
In the coming patches we'll add rpc prepare and done routines
for setting up the sequence op and processing the sequence result.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfs41: nfs4_call_sync]
As per 11-14-08 review.
Squash into "nfs41: introduce nfs4_call_sync" and "nfs41: nfs4_setup_sequence"
Define two functions one for v4 and one for v41
add a pointer to struct nfs4_client to the correct one.
Signed-off-by: Andy Adamson <andros@netapp.com>
[added BUG() in _nfs4_call_sync_session if !CONFIG_NFS_V4_1]
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>
[group minorversion specific stuff together]
Signed-off-by: Alexandros Batsakis <Alexandros.Batsakis@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: fixup nfs4_clear_client_minor_version]
[introduce nfs4_init_client_minor_version() in this patch]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[cleaned-up patch: got rid of nfs_call_sync_t, dprintks, cosmetics, extra server defs]
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 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>
If the asynchronous lease renewal fails (usually due to a soft timeout),
then we _must_ schedule state recovery in order to ensure that we don't
lose the lease unnecessarily or, if the lease is already lost, that we
recover the locking state promptly...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
Remove two unneeded exports and make two symbols static in fs/mpage.c
Cleanup after commit 585d3bc06f
Trim includes of fdtable.h
Don't crap into descriptor table in binfmt_som
Trim includes in binfmt_elf
Don't mess with descriptor table in load_elf_binary()
Get rid of indirect include of fs_struct.h
New helper - current_umask()
check_unsafe_exec() doesn't care about signal handlers sharing
New locking/refcounting for fs_struct
Take fs_struct handling to new file (fs/fs_struct.c)
Get rid of bumping fs_struct refcount in pivot_root(2)
Kill unsharing fs_struct in __set_personality()
Close-to-open cache consistency rules really only require us to flush out
writes on calls to close(), and require us to revalidate attributes on the
very last close of the file.
Currently we appear to be doing a lot of extra attribute revalidation
and cache flushes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The following patch is a combination of a patch by myself and Peter
Staubach.
Trond: If we allow other processes to dirty pages while a process is doing
a consistency sync to disk, we can end up never making progress.
Peter: Attached is a patch which addresses a continuing problem with
the NFS client generating out of order WRITE requests. While
this is compliant with all of the current protocol
specifications, there are servers in the market which can not
handle out of order WRITE requests very well. Also, this may
lead to sub-optimal block allocations in the underlying file
system on the server. This may cause the read throughputs to
be reduced when reading the file from the server.
Peter: There has been a lot of work recently done to address out of
order issues on a systemic level. However, the NFS client is
still susceptible to the problem. Out of order WRITE
requests can occur when pdflush is in the middle of writing
out pages while the process dirtying the pages calls
generic_file_buffered_write which calls
generic_perform_write which calls
balance_dirty_pages_rate_limited which ends up calling
writeback_inodes which ends up calling back into the NFS
client to writes out dirty pages for the same file that
pdflush happens to be working with.
Signed-off-by: Peter Staubach <staubach@redhat.com>
[modification by Trond to merge the two similar patches]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Certain asynchronous operations such as write() do not expect
(or care) that other metadata such as the file owner, mode, acls, ...
change. All they want to do is update and/or check the change attribute,
ctime, and mtime.
By skipping the file owner and group update, we also avoid having to do a
potential idmapper upcall for these asynchronous RPC calls.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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>
Marten Gajda <marten.gajda@fernuni-hagen.de> states:
I tracked the problem down to the function nfs4_do_open_expired.
Within this function _nfs4_open_expired is called and may return
-NFS4ERR_DELAY. When a further call to _nfs4_open_expired is
executed and does not return -NFS4ERR_DELAY the "exception.retry"
variable is not reset to 0, causing the loop to iterate again
(and as long as err != -NFS4ERR_DELAY, probably forever)
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If the client is not using a delegation, the right thing to do is to return
it as soon as possible. This helps reduce the amount of state the server
has to track, as well as reducing the potential for conflicts with other
clients.
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>
Now that we're using the flags to indicate state that needs to be
recovered, as well as having implemented proper refcounting and spinlocking
on the state and open_owners, we can get rid of nfs_client->cl_sem. The
only remaining case that was dubious was the file locking, and that case is
now covered by the nfsi->rwsem.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The unlock path is currently failing to take the nfs_client->cl_sem read
lock, and hence the recovery path may see locks disappear from underneath
it.
Also ensure that it takes the nfs_inode->rwsem read lock so that it there
is no conflict with delegation recalls.
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>
When we can update_open_stateid(), we need to be certain that we don't
race with a delegation return. While we could do this by grabbing the
nfs_client->cl_lock, a dedicated spin lock in the delegation structure
will scale better.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
As not all files have an associated open_context (e.g. device special
files), it is safest to test for the existence of the open context
before de-referencing it.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
All the NFSv4 stateful operations are already protected by other locks (in
particular by the rpc_sequence locks.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
gcc (4.3.0) rightfully warns about this:
/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/fs/nfs/nfs4proc.c: In function nfs4_proc_setclientid_confirm:
/usr0/export/dev/bhalevy/git/linux-pnfs-bh-nfs41/fs/nfs/nfs4proc.c:2936: warning: timeout may be used uninitialized in this function
nfs4_delay that's passed a pointer to 'timeout' is looking at its value
and sets it up to some value in the range: NFS4_POLL_RETRY_MIN..NFS4_POLL_RETRY_MAX
if (*timeout <= 0)
*timeout = NFS4_POLL_RETRY_MIN;
if (*timeout > NFS4_POLL_RETRY_MAX)
*timeout = NFS4_POLL_RETRY_MAX;
Therefore it will end up set to some sane, though rather indeterministic, value.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We're not modifying the nfs_server when we call nfs_inc_server_stats and
friends, so allow the compiler to pass 'const' pointers too.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
All instances are set to nfs_open(), so we should just remove the redundant
indirection. Ditto for the file_release op
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
ftruncate() access checking is supposed to be performed at open() time,
just like reads and writes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Here are some more places where path_{get,put}() can be used instead of
dput()/mntput() pair.
Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
With the recent change to generic creds, we can no longer use
cred->cr_ops->cr_name to distinguish between RPCSEC_GSS principals and
AUTH_SYS/AUTH_NULL identities. Replace it with the rpc_authops->au_name
instead...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It is quite possible that the OPEN, CLOSE, LOCK, LOCKU,... compounds fail
before the actual stateful operation has been executed (for instance in the
PUTFH call). There is no way to tell from the overall status result which
operations were executed from the COMPOUND.
The fix is to move incrementing of the sequence id into the XDR layer,
so that we do it as we process the results from the stateful operation.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
There should be no need to invalidate a perfectly good state owner just
because of a stale filehandle. Doing so can cause the state recovery code
to break, since nfs4_get_renew_cred() and nfs4_get_setclientid_cred() rely
on finding active state owners.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The NFSv4 protocol allows clients to negotiate security protocols on the
fly in the case where an administrator on the server changes the export
settings and/or in the case where we may have a filesystem migration event.
Instead of having the NFS client code cache credentials that are tied to a
particular AUTH method it is therefore preferable to have a generic credential
that can be converted into whatever AUTH is in use by the RPC client when
the read/write/sillyrename/... is put on the wire.
We do this by means of the new "generic" credential, which basically just
caches the minimal information that is needed to look up an RPCSEC_GSS,
AUTH_SYS, or AUTH_NULL credential.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
An audit of the current RPC timeout functions shows that they don't really
ever need to run in the softirq context. As long as the softirq is
able to signal that the wakeup is due to a timeout (which it can do by
setting task->tk_status to -ETIMEDOUT) then the callback functions can just
run as standard task->tk_callback functions (in the rpciod/process
context).
The only possible border-line case would be xprt_timer() for the case of
UDP, when the callback is used to reduce the size of the transport
congestion window. In testing, however, the effect of moving that update
to a callback would appear to be minor.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We want to ensure that rpc_call_ops that involve mntput() are run on nfsiod
rather than on rpciod, so that they don't deadlock when the resulting
umount calls rpc_shutdown_client(). Hence we specify that read, write and
commit calls must complete on nfsiod.
Ditto for NFSv4 open, lock, locku and close asynchronous calls.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This is the central patch of a cleanup series. In most cases there is no good
reason why someone would want to use a dentry for itself. This series reflects
that fact and embeds a struct path into nameidata.
Together with the other patches of this series
- it enforced the correct order of getting/releasing the reference count on
<dentry,vfsmount> pairs
- it prepares the VFS for stacking support since it is essential to have a
struct path in every place where the stack can be traversed
- it reduces the overall code size:
without patch series:
text data bss dec hex filename
5321639 858418 715768 6895825 6938d1 vmlinux
with patch series:
text data bss dec hex filename
5320026 858418 715768 6894212 693284 vmlinux
This patch:
Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix cifs]
[akpm@linux-foundation.org: fix smack]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'task_killable' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc: (22 commits)
Remove commented-out code copied from NFS
NFS: Switch from intr mount option to TASK_KILLABLE
Add wait_for_completion_killable
Add wait_event_killable
Add schedule_timeout_killable
Use mutex_lock_killable in vfs_readdir
Add mutex_lock_killable
Use lock_page_killable
Add lock_page_killable
Add fatal_signal_pending
Add TASK_WAKEKILL
exit: Use task_is_*
signal: Use task_is_*
sched: Use task_contributes_to_load, TASK_ALL and TASK_NORMAL
ptrace: Use task_is_*
power: Use task_is_*
wait: Use TASK_NORMAL
proc/base.c: Use task_is_*
proc/array.c: Use TASK_REPORT
perfmon: Use task_is_*
...
Fixed up conflicts in NFS/sunrpc manually..
Otherwise, there is a potential deadlock if the last dput() from an NFSv4
close() or other asynchronous operation leads to nfs_clear_inode calling
the synchronous delegreturn.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The rfc doesn't give any reason it shouldn't be possible to set an
attribute on a non-regular file. And if the server supports it, then it
shouldn't be up to us to prevent it.
Thanks to Erez for the report and Trond for further analysis.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Tested-by: Erez Zadok <ezk@cs.sunysb.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We recently added methods to RPC transports that provide string versions of
the remote peer address information. Convert the NFSv4 SETCLIENTID
procedure to use those methods instead of building the client ID out of
whole cloth.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Aurelien Charbon <aurelien.charbon@ext.bull.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Replace use of rpc_call_setup() with rpc_init_task(), and in cases where we
need to initialise task->tk_action, with rpc_call_start().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Move the common code for setting up the nfs_write_data and nfs_read_data
structures into fs/nfs/read.c, fs/nfs/write.c and fs/nfs/direct.c.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Reduce the time spent locking the rpc_sequence structure by queuing the
nfs_seqid only when we are ready to take the lock (when calling
nfs_wait_on_sequence).
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFSv4 file locking is currently completely broken since it doesn't respect
the OPEN sequencing when it is given an unconfirmed lock_owner and needs to
do an open_to_lock_owner. Worse: it breaks the sunrpc rules by doing a
GFP_KERNEL allocation inside an rpciod callback.
Fix is to preallocate the open seqid structure in nfs4_alloc_lockdata if we
see that the lock_owner is unconfirmed.
Then, in nfs4_lock_prepare() we wait for either the open_seqid, if
the lock_owner is still unconfirmed, or else fall back to waiting on the
standard lock_seqid.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
RFC3530 states that the open_owner is confirmed if and only if the client
sends an OPEN_CONFIRM request with the appropriate sequence id and stateid
within the lease period.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
By using the TASK_KILLABLE infrastructure, we can get rid of the 'intr'
mount option. We have to use _killable everywhere instead of _interruptible
as we get rid of rpc_clnt_sigmask/sigunmask.
Signed-off-by: Liam R. Howlett <howlett@gmail.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
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>
lookup() and sillyrename() can race one another because the sillyrename()
completion cannot take the parent directory's inode->i_mutex since the
latter may be held by whoever is calling dput().
We therefore have little option but to add extra locking to ensure that
nfs_lookup() and nfs_atomic_open() do not race with the sillyrename
completion.
If somebody has looked up the sillyrenamed file in the meantime, we just
transfer the sillydelete information to the new dentry.
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>
We're failing basic test6 against Linux servers because they lack a correct
change attribute. The fix is to assume that we always want to invalidate
the readdir caches when we call update_changeattr and/or
nfs_post_op_update_inode on a directory.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
nfs_post_op_update_inode() is really only meant to be used if we expect the
inode and its attributes to have changed in some way.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We don't want to leave an unverified hashed negative dentry if the
exclusive create fails to complete.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFSv2 and v4 don't offer weak cache consistency attributes on WRITE calls.
In NFSv3, returning wcc data is optional. In all cases, we want to prevent
the client from invalidating our cached data whenever ->write_done()
attempts to update the inode attributes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFSv3 will correctly update atime on a read() call, so there is no need to
set the NFS_INO_INVALID_ATIME flag unless the call to nfs_refresh_inode()
fails.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFSv3 will correctly update atime on a readdir call, so there is no need to
set the NFS_INO_INVALID_ATIME flag unless the call to nfs_refresh_inode()
fails.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The reason is that if the weak cache consistency update was successful,
then we know that our client must be the only one that changed the
directory, and we've already updated the dcache to reflect the change.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It doesn't really make sense to cache an access call without also
revalidating the attributes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, _nfs4_do_access() is just a copy of nfs_do_access() with added
conversion of the open flags into an access mask. This patch merges the
duplicate functionality.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Hi.
Attached is a patch to modify the NFS client code to support
64 bit ino's, as appropriate for the system and the NFS
protocol version.
The code basically just expand the NFS interfaces for routines
which handle ino's from using ino_t to u64 and then uses the
fileid in the nfs_inode instead of i_ino in the inode. The
code paths that were updated are in the getattr method and
the readdir methods.
This should be no real change on 64 bit platforms. Since
the ino_t is an unsigned long, it would already be 64 bits
wide.
Thanx...
ps
Signed-off-by: Peter Staubach <staubach@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Do not allow cached open for O_RDONLY or O_WRONLY unless the file has been
previously opened in these modes.
Also Fix the calculation of the mode in nfs4_close_prepare. We should only
issue an OPEN_DOWNGRADE if we're sure that we will still be holding the
correct open modes. This may not be the case if we've been doing delegated
opens.
Finally, there is no need to adjust the open mode bit flags in
nfs4_close_done(): that has already been done in nfs4_close_prepare().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Fix a couple of bugs:
- Don't rely on the parent dentry still being valid when the call completes.
Fixes a race with shrink_dcache_for_umount_subtree()
- Don't remove the file if the filehandle has been labelled as stale.
Fix a couple of inefficiencies
- Remove the global list of sillyrenamed files. Instead we can cache the
sillyrename information in the dentry->d_fsdata
- Move common code from unlink_setup/unlink_done into fs/nfs/unlink.c
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We need a common structure for setting up an unlink() rpc call in order to
fix the asynchronous unlink code.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Ensure that opendata->state is always initialised when we do state
recovery.
Ensure that we set the filehandle in the case where we're doing an
"OPEN_CLAIM_PREVIOUS" call due to a server reboot.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
I ran into a curious issue when a lock is being canceled. The
cancellation results in a lock request to the vfs layer instead of an
unlock request. This is particularly insidious when the process that
owns the lock is exiting. In that case, sometimes the erroneous lock is
applied AFTER the process has entered zombie state, preventing the lock
from ever being released. Eventually other processes block on the lock
causing a slow degredation of the system. In the 2.6.16 kernel this was
investigated on, the problem is compounded by the fact that the cl_sem
is held while blocking on the vfs lock, which results in most processes
accessing the nfs file system in question hanging.
In more detail, here is how the situation occurs:
first _nfs4_do_setlk():
static int _nfs4_do_setlk(struct nfs4_state *state, int cmd, struct file_lock *fl, int reclaim)
...
ret = nfs4_wait_for_completion_rpc_task(task);
if (ret == 0) {
...
} else
data->cancelled = 1;
then nfs4_lock_release():
static void nfs4_lock_release(void *calldata)
...
if (data->cancelled != 0) {
struct rpc_task *task;
task = nfs4_do_unlck(&data->fl, data->ctx, data->lsp,
data->arg.lock_seqid);
The problem is the same file_lock that was passed in to _nfs4_do_setlk()
gets passed to nfs4_do_unlck() from nfs4_lock_release(). So the type is
still F_RDLCK or FWRLCK, not F_UNLCK. At some point, when cancelling the
lock, the type needs to be changed to F_UNLCK. It seemed easiest to do
that in nfs4_do_unlck(), but it could be done in nfs4_lock_release().
The concern I had with doing it there was if something still needed the
original file_lock, though it turns out the original file_lock still
needs to be modified by nfs4_do_unlck() because nfs4_do_unlck() uses the
original file_lock to pass to the vfs layer, and a copy of the original
file_lock for the RPC request.
It seems like the simplest solution is to force all situations where
nfs4_do_unlck() is being used to result in an unlock, so with that in
mind, I made the following change:
Signed-off-by: Frank Filz <ffilzlnx@us.ibm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Rely on nfs4_try_open_cached() when appropriate.
Also fix an RCU violation in _nfs4_do_open_reclaim()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If we already have a stateid with the correct open mode for a given file,
then we can reuse that stateid instead of re-issuing an OPEN call without
violating the close-to-open caching semantics.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We should not be calling open() on an inode that has a delegation unless
we're doing a reclaim.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This ensures that nfs4_open_release() and nfs4_open_confirm_release()
can now handle an eventual delegation that was returned with out open.
As such, it fixes a delegation "leak" when the user breaks out of an open
call.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently we do not check for the FMODE_EXEC flag as we should. For that
particular case, we need to perform an ACCESS call to the server in order
to check that the file is executable.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The Linux NFS4 client simply skips over the bitmask in an O_EXCL open
call and so it doesn't bother to reset any fields that may be holding
the verifier. This patch has us save the first two words of the bitmask
(which is all the current client has #defines for). The client then
later checks this bitmask and turns on the appropriate flags in the
sattr->ia_verify field for the following SETATTR call.
This patch only currently checks to see if the server used the atime
and mtime slots for the verifier (which is what the Linux server uses
for this). I'm not sure of what other fields the server could
reasonably use, but adding checks for others should be trivial.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
nfs4_do_close() does not currently have any way to ensure that the user
won't attempt to unmount the partition while the asynchronous RPC call
is completing. This again may cause Oopses in nfs_update_inode().
Add a vfsmount argument to nfs4_close_state to ensure that the partition
remains mounted while we're closing the file.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>