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* nfsd41: move channel attributes from nfsd4_session to a nfsd4_channel_attr ↵Alexandros Batsakis2009-06-161-11/+0
| | | | | | | | | | struct the change is valid for both the forechannel and the backchannel (currently dummy) Signed-off-by: Alexandros Batsakis <Alexandros.Batsakis@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd: support ext4 i_versionJ. Bruce Fields2009-04-291-4/+13
| | | | | | | | | | | | | | | | 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: J. Bruce Fields <bfields@citi.umich.edu> Cc: Theodore Tso <tytso@mit.edu>
* nfsd41: CREATE_EXCLUSIVE4_1Benny Halevy2009-04-031-6/+4
| | | | | | | | | | | | | | 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: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd41: support for 3-word long attribute bitmaskAndy Adamson2009-04-031-6/+6
| | | | | | | Also, use client minorversion to generate supported attrs Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd41: access_validAndy Adamson2009-04-031-0/+1
| | | | | | | | For nfs41, the open share flags are used also for delegation "wants" and "signals". Check that they are valid. Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd41: stateid handlingAndy Adamson2009-04-031-1/+7
| | | | | | | | | | | | | | | | | | | | | | 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: Benny Halevy <bhalevy@panasas.com> Signed-off-by: Andy Adamson <andros@netapp.com> [nfsd4_has_session should return a boolean, not u32] Signed-off-by: Benny 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: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd41: destroy_session operationBenny Halevy2009-04-031-1/+1
| | | | | | | | | 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: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd41: non-page DRC for solo sequence responsesAndy Adamson2009-04-031-1/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Andy Adamson <andros@netapp.com> Signed-off-by: Benny 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: Andy Adamson <andros@netapp.com> [changed return type to bool] Signed-off-by: Benny Halevy <bhalevy@panasas.com> [nfsd41 drop parens in nfsd4_is_solo_sequence call] Signed-off-by: Andy Adamson <andros@netapp.com> [changed "== 0" to "!"] Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd41: create_session operationAndy Adamson2009-04-031-1/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Marc Eshel <eshel@almaden.ibm.com> Signed-off-by: Dean 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: Andy Adamson <andros@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> [use sessionid_lock spin lock] [nfsd41: use bool inuse for slot state] Signed-off-by: Benny Halevy <bhalevy@panasas.com> [nfsd41 remove sl_session from alloc_init_session] Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Benny 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: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd41: nfsd DRC logicAndy Adamson2009-04-031-0/+1
| | | | | | | | | | | | | | | | | | 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: Benny Halevy <bhalevy@panasas.com> [nfsd41: use bool inuse for slot state] Signed-off-by: Benny Halevy <bhalevy@panasas.com> [nfsd41: use cstate session in nfs4svc_encode_compoundres] [nfsd41 replace nfsd4_set_cache_entry] Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd41: DRC save, restore, and clear functionsAndy Adamson2009-04-031-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Cache all the result pages, including the rpc header in rq_respages[0], for a request in the slot table cache entry. Cache the statp pointer from nfsd_dispatch which points into rq_respages[0] just past the rpc header. When setting a cache entry, calculate and save the length of the nfs data minus the rpc header for rq_respages[0]. When replaying a cache entry, replace the cached rpc header with the replayed request rpc result header, unless there is not enough room in the cached results first page. In that case, use the cached rpc header. The sessions fore channel maxresponse size cached is set to NFSD_PAGES_PER_SLOT * PAGE_SIZE. For compounds we are cacheing with operations such as READDIR that use the xdr_buf->pages to hold data, we choose to cache the extra page of data rather than copying data from xdr_buf->pages into the xdr_buf->head page. [nfsd41: limit cache to maxresponsesize_cached] [nfsd41: mv nfsd4_set_statp under CONFIG_NFSD_V4_1] [nfsd41: rename nfsd4_move_pages] [nfsd41: rename page_no variable] [nfsd41: rename nfsd4_set_cache_entry] [nfsd41: fix nfsd41_copy_replay_data comment] [nfsd41: add to nfsd4_set_cache_entry] Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd41: sequence operationBenny Halevy2009-04-031-1/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Benny Halevy <bhalevy@panasas.com> [nfsd: add a struct nfsd4_slot pointer to struct nfsd4_compound_state] Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Benny 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: Andy Adamson <andros@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> [simplify nfsd4_encode_sequence error handling] Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd41: exchange_id operationAndy Adamson2009-04-031-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: Benny Halevy <bhalevy@panasas.com> Signed-off-by: Andy Adamosn <andros@netapp.com> Signed-off-by: Benny 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: Mike Sager <sager@netapp.com> Signed-off-by: Benny 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: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd41: proc stubsAndy Adamson2009-04-031-0/+12
| | | | | Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd41: xdr infrastructureAndy Adamson2009-04-031-0/+22
| | | | | | | | | | | | | | | | | 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: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd: embed nfsd4_current_state in nfsd4_compoundresAndy Adamson2009-03-291-4/+5
| | | | | | | | Remove the allocation of struct nfsd4_compound_state. Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* nfsd: Allow AIX client to read dir containing mountpointsFrank Filz2008-02-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch addresses a compatibility issue with a Linux NFS server and AIX NFS client. I have exported /export as fsid=0 with sec=krb5:krb5i I have mount --bind /home onto /export/home I have exported /export/home with sec=krb5i The AIX client mounts / -o sec=krb5:krb5i onto /mnt If I do an ls /mnt, the AIX client gets a permission error. Looking at the network traceIwe see a READDIR looking for attributes FATTR4_RDATTR_ERROR and FATTR4_MOUNTED_ON_FILEID. The response gives a NFS4ERR_WRONGSEC which the AIX client is not expecting. Since the AIX client is only asking for an attribute that is an attribute of the parent file system (pseudo root in my example), it seems reasonable that there should not be an error. In discussing this issue with Bruce Fields, I initially proposed ignoring the error in nfsd4_encode_dirent_fattr() if all that was being asked for was FATTR4_RDATTR_ERROR and FATTR4_MOUNTED_ON_FILEID, however, Bruce suggested that we avoid calling cross_mnt() if only these attributes are requested. The following patch implements bypassing cross_mnt() if only FATTR4_RDATTR_ERROR and FATTR4_MOUNTED_ON_FILEID are called. Since there is some complexity in the code in nfsd4_encode_fattr(), I didn't want to duplicate code (and introduce a maintenance nightmare), so I added a parameter to nfsd4_encode_fattr() that indicates whether it should ignore cross mounts and simply fill in the attribute using the passed in dentry as opposed to it's parent. Signed-off-by: Frank Filz <ffilzlnx@us.ibm.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
* knfsd: 64 bit ino support for NFS serverPeter Staubach2007-10-091-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | Modify the NFS server code to support 64 bit ino's, as appropriate for the system and the NFS protocol version. The gist of the changes is to query the underlying file system for attributes and not just to use the cached attributes in the inode. For this specific purpose, the inode only contains an ino field which unsigned long, which is large enough on 64 bit platforms, but is not large enough on 32 bit platforms. I haven't been able to find any reason why ->getattr can't be called while i_mutex. The specification indicates that i_mutex is not required to be held in order to invoke ->getattr, but it doesn't say that i_mutex can't be held while invoking ->getattr. I also haven't come to any conclusions regarding the value of lease_get_mtime() and whether it should or should not be invoked by fill_post_wcc() too. I chose not to change this because I thought that it was safer to leave well enough alone. If we decide to make a change, it can be done separately. Signed-off-by: Peter Staubach <staubach@redhat.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Acked-by: Neil Brown <neilb@suse.de>
* knfsd: nfsd4: implement secinfoAndy Adamson2007-07-171-0/+7
| | | | | | | | | | | | | Implement the secinfo operation. (Thanks to Usha Ketineni wrote an earlier version of this support.) Cc: Usha Ketineni <uketinen@us.ibm.com> Signed-off-by: Andy Adamson <andros@citi.umich.edu> Signed-off-by: "J. Bruce Fields" <bfields@citi.umich.edu> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] knfsd: nfsd4: reorganize compound opsJ.Bruce Fields2006-12-131-0/+5
| | | | | | | | | Define an op descriptor struct, use it to simplify nfsd4_proc_compound(). Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] knfsd: nfsd4: move replay_owner to cstateJ.Bruce Fields2006-12-131-10/+7
| | | | | | | | | Tuck away the replay_owner in the cstate while we're at it. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] knfsd: nfsd4: pass saved and current fh together into nfsd4 operationsJ.Bruce Fields2006-12-131-7/+15
| | | | | | | | | | | | | | | | Pass the saved and current filehandles together into all the nfsd4 compound operations. I want a unified interface to these operations so we can just call them by pointer and throw out the huge switch statement. Also I'll eventually want a structure like this--that holds the state used during compound processing--for deferral. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] nfsd: nfs4 code returns error values in net-endianAl Viro2006-10-201-15/+15
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no> Acked-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] xdr annotations: NFSv4 serverAl Viro2006-10-201-12/+12
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no> Acked-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] knfsd: Avoid excess stack usage in svc_tcp_recvfromNeilBrown2006-10-041-2/+0
| | | | | | | | | | | | | | | | | | .. by allocating the array of 'kvec' in 'struct svc_rqst'. As we plan to increase RPCSVC_MAXPAGES from 8 upto 256, we can no longer allocate an array of this size on the stack. So we allocate it in 'struct svc_rqst'. However svc_rqst contains (indirectly) an array of the same type and size (actually several, but they are in a union). So rather than waste space, we move those arrays out of the separately allocated union and into svc_rqst to share with the kvec moved out of svc_tcp_recvfrom (various arrays are used at different times, so there is no conflict). Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] nfsd4: rename lk_stateownerJ. Bruce Fields2006-01-181-2/+3
| | | | | | | | | | | | | One of the things that's confusing about nfsd4_lock is that the lk_stateowner field could be set to either of two different lockowners: the open owner or the lock owner. Rename to lk_replay_owner and add a comment to make it clear that it's used for whichever stateowner has its sequence id bumped for replay detection. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] nfsd4: move replay_ownerNeil Brown2005-09-131-5/+10
| | | | | | | | | | It seems more natural to move the setting of the replay_owner into the relevant procedure instead of doing it in nfsv4_proc_compound. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] knfsd: nfsd4: delegation recoveryNeilBrown2005-06-241-0/+1
| | | | | | | | | Allow recovery of delegations after reboot. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+463
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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