Use NFSD_SLOT_CACHE_SIZE size buffers for sessions DRC instead of holding nfsd
pages in cache.

Connectathon testing has shown that 1024 bytes for encoded compound operation
responses past the sequence operation is sufficient, 512 bytes is a little too
small. Set NFSD_SLOT_CACHE_SIZE to 1024.

Allocate memory for the session DRC in the CREATE_SESSION operation
to guarantee that the memory resource is available for caching responses.
Allocate each slot individually in preparation for slot table size negotiation.

Remove struct nfsd4_cache_entry and helper functions for the old page-based
DRC.

The iov_len calculation in nfs4svc_encode_compoundres is now always
correct.  Replay is now done in nfsd4_sequence under the state lock, so
the session ref count is only bumped on non-replay. Clean up the
nfs4svc_encode_compoundres session logic.

The nfsd4_compound_state statp pointer is also not used.
Remove nfsd4_set_statp().

Move useful nfsd4_cache_entry fields into nfsd4_slot.

Signed-off-by: Andy Adamson <andros@netapp.com
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

The fact that the filesystem doesn't currently list any alternate
locations does _not_ imply that the fs_locations attribute should be
marked as "unsupported".
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Instead of trying to share the generic 4.1 reply cache code for the
CREATE_SESSION reply cache, it's simpler to handle CREATE_SESSION
separately.

The nfs41 single slot clientid DRC holds the results of create session
processing.  CREATE_SESSION can be preceeded by a SEQUENCE operation
(an embedded CREATE_SESSION) and the create session single slot cache must be
maintained.  nfsd4_replay_cache_entry() and nfsd4_store_cache_entry() do not
implement the replay of an embedded CREATE_SESSION.

The clientid DRC slot does not need the inuse, cachethis or other fields that
the multiple slot session cache uses.  Replace the clientid DRC cache struct
nfs4_slot cache with a new nfsd4_clid_slot cache.  Save the xdr struct
nfsd4_create_session into the cache at the end of processing, and on a replay,
replace the struct for the replay request with the cached version all while
under the state lock.

nfsd4_proc_compound will handle both the solo and embedded CREATE_SESSION case
via the normal use of encode_operation.

Errors that do not change the create session cache:
A create session NFS4ERR_STALE_CLIENTID error means that a client record
(and associated create session slot) could not be found and therefore can't
be changed.  NFSERR_SEQ_MISORDERED errors do not change the slot cache.

All other errors get cached.

Remove the clientid DRC specific check in nfs4svc_encode_compoundres to
put the session only if cstate.session is set which will now always be true.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

the change is valid for both the forechannel and the backchannel (currently dummy)
Signed-off-by: NAlexandros Batsakis <Alexandros.Batsakis@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Server should return NFS4ERR_ATTRNOTSUPP if an attribute specified is
not supported in current environment.
Operations CREATE, NVERIFY, OPEN, SETATTR and VERIFY should do this check.

This bug is found when do newpynfs tests. The names of the tests that failed
are following:
  CR12 NVF7a NVF7b NVF7c NVF7d NVF7f NVF7r NVF7s
  OPEN15 VF7a VF7b VF7c VF7d VF7f VF7r VF7s

Add function do_check_fattr() to do exact check:
1, Check attribute specified is supported by the NFSv4 server or not.
2, Check FATTR4_WORD0_ACL & FATTR4_WORD0_FS_LOCATIONS are supported
   in current environment or not.
3, Check attribute specified is writable or not.

step 1 and 3 are done in function nfsd4_decode_fattr() but removed
to this function now.
Signed-off-by: NYu Zhiguo <yuzg@cn.fujitsu.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

After 2f9092e1 "Fix i_mutex vs.  readdir
handling in nfsd" (and 14f7dd63 "Copy XFS readdir hack into nfsd code"),
an entry may be removed between the first mutex_unlock and the second
mutex_lock. In this case, lookup_one_len() will return a negative
dentry.  Check for this case to avoid a NULL dereference.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Reviewed-by: NJ. R. Okajima <hooanon05@yahoo.co.jp>
Cc: stable@kernel.org

Eliminate 56 sparse warnings like this one:

fs/nfsd/nfs4xdr.c:1331:15: warning: obsolete array initializer, use C99 syntax
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

ext4 supports a real NFSv4 change attribute, which is bumped whenever
the ctime would be updated, including times when two updates arrive
within a jiffy of each other.  (Note that although ext4 has space for
nanosecond-precision ctime, the real resolution is lower: it actually
uses jiffies as the time-source.)  This ensures clients will invalidate
their caches when they need to.

There is some fear that keeping the i_version up-to-date could have
performance drawbacks, so for now it's turned on only by a mount option.
We hope to do something better eventually.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Cc: Theodore Tso <tytso@mit.edu>

We don't need comments to tell us these macros are ugly.  And we're long
past trying to share any of this code with the BSD's.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

This macro doesn't serve any useful purpose.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Implement the CREATE_EXCLUSIVE4_1 open mode conforming to
http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-26

This mode allows the client to atomically create a file
if it doesn't exist while setting some of its attributes.

It must be implemented if the server supports persistent
reply cache and/or pnfs.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Return bitmask for supported EXCLUSIVE4_1 create attributes.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Also, use client minorversion to generate supported attrs
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

In preparation for EXCLUSIVE4_1
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Extract the clientid from sessionid to set the op_clientid on open.
Verify that the clid for other stateful ops is zero for minorversion != 0
Do all other checks for stateful ops without sessions.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NAndy Adamson <andros@netapp.com>
[fixed whitespace indent]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfsd41 remove sl_session from nfsd4_open]
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Calculate the space the compound response has taken after encoding the current
operation.

pad: add on 8 bytes for the next operation's op_code and status so that
there is room to cache a failure on the next operation.

Compare this length to the session se_fmaxresp_cached and return
nfserr_rep_too_big_to_cache if the length is too large.

Our se_fmaxresp_cached will always be a multiple of PAGE_SIZE, and so
will be at least a page and will therefore hold the xdr_buf head.
Signed-off-by: NAndy Adamson <andros@netapp.com>
[nfsd41: non-page DRC for solo sequence responses]
[fixed nfsd4_check_drc_limit cosmetics]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfsd41: use cstate session in nfsd4_check_drc_limit]
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

When sessions are used, stateful operation sequenceid and stateid handling
are not used. When sessions are used,  on the first open set the seqid to 1,
mark state confirmed and skip seqid processing.

When sessionas are used the stateid generation number is ignored when it is zero
whereas without sessions bad_stateid or stale stateid is returned.

Add flags to propagate session use to all stateful ops and down to
check_stateid_generation.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NAndy Adamson <andros@netapp.com>
[nfsd4_has_session should return a boolean, not u32]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfsd41: pass nfsd4_compoundres * to nfsd4_process_open1]
[nfsd41: calculate HAS_SESSION in nfs4_preprocess_stateid_op]
[nfsd41: calculate HAS_SESSION in nfs4_preprocess_seqid_op]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Implement the destory_session operation confoming to
http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-26

[use sessionid_lock spin lock]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

A session inactivity time compound (lease renewal) or a compound where the
sequence operation has sa_cachethis set to FALSE do not require any pages
to be held in the v4.1 DRC. This is because struct nfsd4_slot is already
caching the session information.

Add logic to the nfs41 server to not cache response pages for solo sequence
responses.

Return nfserr_replay_uncached_rep on the operation following the sequence
operation when sa_cachethis is FALSE.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfsd41: use cstate session in nfsd4_replay_cache_entry]
[nfsd41: rename nfsd4_no_page_in_cache]
[nfsd41 rename nfsd4_enc_no_page_replay]
[nfsd41 nfsd4_is_solo_sequence]
[nfsd41 change nfsd4_not_cached return]
Signed-off-by: NAndy Adamson <andros@netapp.com>
[changed return type to bool]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfsd41 drop parens in nfsd4_is_solo_sequence call]
Signed-off-by: NAndy Adamson <andros@netapp.com>
[changed "== 0" to "!"]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Implement the create_session operation confoming to
http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-26

Look up the client id (generated by the server on exchange_id,
given by the client on create_session).
If neither a confirmed or unconfirmed client is found
then the client id is stale
If a confirmed cilent is found (i.e. we already received
create_session for it) then compare the sequence id
to determine if it's a replay or possibly a mis-ordered rpc.
If the seqid is in order, update the confirmed client seqid
and procedd with updating the session parameters.

If an unconfirmed client_id is found then verify the creds
and seqid.  If both match move the client id to confirmed state
and proceed with processing the create_session.

Currently, we do not support persistent sessions, and RDMA.

alloc_init_session generates a new sessionid and creates
a session structure.

NFSD_PAGES_PER_SLOT is used for the max response cached calculation, and for
the counting of DRC pages using the hard limits set in struct srv_serv.

A note on NFSD_PAGES_PER_SLOT:

Other patches in this series allow for NFSD_PAGES_PER_SLOT + 1 pages to be
cached in a DRC slot when the response size is less than NFSD_PAGES_PER_SLOT *
PAGE_SIZE but xdr_buf pages are used. e.g. a READDIR operation will encode a
small amount of data in the xdr_buf head, and then the READDIR in the xdr_buf
pages.  So, the hard limit calculation use of pages by a session is
underestimated by the number of cached operations using the xdr_buf pages.

Yet another patch caches no pages for the solo sequence operation, or any
compound where cache_this is False.  So the hard limit calculation use of
pages by a session is overestimated by the number of these operations in the
cache.

TODO: improve resource pre-allocation and negotiate session
parameters accordingly.  Respect and possibly adjust
backchannel attributes.
Signed-off-by: NMarc Eshel <eshel@almaden.ibm.com>
Signed-off-by: NDean Hildebrand <dhildeb@us.ibm.com>
[nfsd41: remove headerpadsz from channel attributes]
Our client and server only support a headerpadsz of 0.
[nfsd41: use DRC limits in fore channel init]
[nfsd41: do not change CREATE_SESSION back channel attrs]
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[use sessionid_lock spin lock]
[nfsd41: use bool inuse for slot state]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfsd41 remove sl_session from alloc_init_session]
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[simplify nfsd4_encode_create_session error handling]
[nfsd41: fix comment style in init_forechannel_attrs]
[nfsd41: allocate struct nfsd4_session and slot table in one piece]
[nfsd41: no need to INIT_LIST_HEAD in alloc_init_session just prior to list_add]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Replay a request in nfsd4_sequence.
Add a minorversion to struct nfsd4_compound_state.

Pass the current slot to nfs4svc_encode_compound res via struct
nfsd4_compoundres to set an NFSv4.1 DRC entry.

Signed-off-by: Andy Adamson<andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfsd41: use bool inuse for slot state]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfsd41: use cstate session in nfs4svc_encode_compoundres]
[nfsd41 replace nfsd4_set_cache_entry]
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Implement the sequence operation conforming to
http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-26

Check for stale clientid (as derived from the sessionid).
Enforce slotid range and exactly-once semantics using
the slotid and seqid.

If everything went well renew the client lease and
mark the slot INPROGRESS.

Add a struct nfsd4_slot pointer to struct nfsd4_compound_state.
To be used for sessions DRC replay.

[nfsd41: rename sequence catchthis to cachethis]
Signed-off-by: Andy Adamson<andros@netapp.com>
[pulled some code to set cstate->slot from "nfsd DRC logic"]
[use sessionid_lock spin lock]
[nfsd41: use bool inuse for slot state]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfsd: add a struct nfsd4_slot pointer to struct nfsd4_compound_state]
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfsd41: add nfsd4_session pointer to nfsd4_compound_state]
[nfsd41: set cstate session]
[nfsd41: use cstate session in nfsd4_sequence]
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[simplify nfsd4_encode_sequence error handling]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Implement the exchange_id operation confoming to
http://tools.ietf.org/html/draft-ietf-nfsv4-minorversion1-28

Based on the client provided name, hash a client id.
If a confirmed one is found, compare the op's creds and
verifier.  If the creds match and the verifier is different
then expire the old client (client re-incarnated), otherwise,
if both match, assume it's a replay and ignore it.

If an unconfirmed client is found, then copy the new creds
and verifer if need update, otherwise assume replay.

The client is moved to a confirmed state on create_session.

In the nfs41 branch set the exchange_id flags to
EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_SUPP_MOVED_REFER
(pNFS is not supported, Referrals are supported,
Migration is not.).

Address various scenarios from section 18.35 of the spec:

1. Check for EXCHGID4_FLAG_UPD_CONFIRMED_REC_A and set
   EXCHGID4_FLAG_CONFIRMED_R as appropriate.

2. Return error codes per 18.35.4 scenarios.

3. Update client records or generate new client ids depending on
   scenario.

Note: 18.35.4 case 3 probably still needs revisiting.  The handling
seems not quite right.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NAndy Adamosn <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfsd41: use utsname for major_id (and copy to server_scope)]
[nfsd41: fix handling of various exchange id scenarios]
Signed-off-by: NMike Sager <sager@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfsd41: reverse use of EXCHGID4_INVAL_FLAG_MASK_A]
[simplify nfsd4_encode_exchange_id error handling]
[nfsd41: embed an xdr_netobj in nfsd4_exchange_id]
[nfsd41: return nfserr_serverfault for spa_how == SP4_MACH_CRED]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Define nfsd41_dec_ops vector and add it to nfsd4_minorversion for
minorversion 1.

Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
since we don't need to filter out obsolete ops as this is
done in the decoding phase.

exchange_id, create_session, destroy_session, and sequence ops are
implemented as stubs returning nfserr_opnotsupp at this stage.

[was nfsd41: xdr stubs]
[get rid of CONFIG_NFSD_V4_1]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Currently putpubfh returns NFSERR_OPNOTSUPP, which isn't actually
allowed for v4.  The right error is probably NFSERR_NOTSUPP.

But let's just implement it; though rarely seen, it can be used by
Solaris (with a special mount option), is mandated by the rfc, and is
trivial for us to support.

Thanks to Yang Hongyang for pointing out the original problem, and to
Mike Eisler, Tom Talpey, Trond Myklebust, and Dave Noveck for further
argument....
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Thanks for Bill Baker at sun.com for catching this
at Connectathon 2009.

This bug was introduced in 2.6.27
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Although this operation is unsupported by our implementation
we still need to provide an encode routine for it to
merely encode its (error) status back in the compound reply.

Thanks for Bill Baker at sun.com for testing with the Sun
OpenSolaris' client, finding, and reporting this bug at
Connectathon 2009.

This bug was introduced in 2.6.27
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Cc: stable@kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

After using the encode_stateid helper the "p" pointer declared
by ENCODE_SEQID_OP_HEAD is warned as unused.
In the single site where it is still needed it can be declared
separately using the ENCODE_HEAD macro.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

nfsd4_encode_open first reservation is currently for 36 + sizeof(stateid_t)
while it writes after the stateid a cinfo (20 bytes) and 5 more 4-bytes
words, for a total of 40 + sizeof(stateid_t).
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

The WRITEMEM macro produces sparse warnings of the form:
fs/nfsd/nfs4xdr.c:2668:2: warning: do-while statement is not a compound statement
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Cc: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Thanks to problem report and original patch from Harvey Harrison.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Cc: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Benny Halevy <bhalevy@panasas.com>

In preparation for minorversion 1

All encoders now return an nfserr status (typically their
nfserr argument).  Unsupported ops go through nfsd4_encode_operation
too, so use nfsd4_encode_noop to encode nothing for their reply body.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Have separate vectors of operation decoders for each minorversion.
Obsolete ops in newer minorversions have default implementation returning
nfserr_opnotsupp.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

nfserr_opnotsupp should be returned for unsupported nfs4 ops
rather than nfserr_op_illegal.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

In preparation for minorversion 1
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>