From b85d4c01b76f6969a085d07a767fa45225cb14be Mon Sep 17 00:00:00 2001 From: Benny Halevy Date: Fri, 3 Apr 2009 08:28:08 +0300 Subject: [PATCH] nfsd41: sequence operation 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 [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 [nfsd: add a struct nfsd4_slot pointer to struct nfsd4_compound_state] Signed-off-by: Andy Adamson Signed-off-by: Benny Halevy [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 Signed-off-by: Benny Halevy [simplify nfsd4_encode_sequence error handling] Signed-off-by: Benny Halevy Signed-off-by: J. Bruce Fields --- fs/nfsd/nfs4state.c | 73 +++++++++++++++++++++++++++++++++++++-- fs/nfsd/nfs4xdr.c | 33 ++++++++++++++++-- include/linux/nfsd/xdr4.h | 13 ++++++- 3 files changed, 113 insertions(+), 6 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index dfc6d946cdfe..24b6e0593184 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -1000,6 +1000,32 @@ nfsd4_exchange_id(struct svc_rqst *rqstp, return status; } +static int +check_slot_seqid(u32 seqid, struct nfsd4_slot *slot) +{ + dprintk("%s enter. seqid %d slot->sl_seqid %d\n", __func__, seqid, + slot->sl_seqid); + + /* The slot is in use, and no response has been sent. */ + if (slot->sl_inuse) { + if (seqid == slot->sl_seqid) + return nfserr_jukebox; + else + return nfserr_seq_misordered; + } + /* Normal */ + if (likely(seqid == slot->sl_seqid + 1)) + return nfs_ok; + /* Replay */ + if (seqid == slot->sl_seqid) + return nfserr_replay_cache; + /* Wraparound */ + if (seqid == 1 && (slot->sl_seqid + 1) == 0) + return nfs_ok; + /* Misordered replay or misordered new request */ + return nfserr_seq_misordered; +} + __be32 nfsd4_create_session(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, @@ -1017,11 +1043,54 @@ nfsd4_destroy_session(struct svc_rqst *r, } __be32 -nfsd4_sequence(struct svc_rqst *r, +nfsd4_sequence(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, struct nfsd4_sequence *seq) { - return -1; /* stub */ + struct nfsd4_session *session; + struct nfsd4_slot *slot; + int status; + + spin_lock(&sessionid_lock); + status = nfserr_badsession; + session = find_in_sessionid_hashtbl(&seq->sessionid); + if (!session) + goto out; + + status = nfserr_badslot; + if (seq->slotid >= session->se_fnumslots) + goto out; + + slot = &session->se_slots[seq->slotid]; + dprintk("%s: slotid %d\n", __func__, seq->slotid); + + status = check_slot_seqid(seq->seqid, slot); + if (status == nfserr_replay_cache) { + cstate->slot = slot; + cstate->session = session; + goto replay_cache; + } + if (status) + goto out; + + /* Success! bump slot seqid */ + slot->sl_inuse = true; + slot->sl_seqid = seq->seqid; + + cstate->slot = slot; + cstate->session = session; + +replay_cache: + /* Renew the clientid on success and on replay. + * Hold a session reference until done processing the compound: + * nfsd4_put_session called only if the cstate slot is set. + */ + renew_client(session->se_client); + nfsd4_get_session(session); +out: + spin_unlock(&sessionid_lock); + dprintk("%s: return %d\n", __func__, ntohl(status)); + return status; } __be32 diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index bebf6d249069..8556575480ce 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -1113,7 +1113,16 @@ static __be32 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp, struct nfsd4_sequence *seq) { - return nfserr_opnotsupp; /* stub */ + DECODE_HEAD; + + READ_BUF(NFS4_MAX_SESSIONID_LEN + 16); + COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN); + READ32(seq->seqid); + READ32(seq->slotid); + READ32(seq->maxslots); + READ32(seq->cachethis); + + DECODE_TAIL; } static __be32 @@ -2828,8 +2837,26 @@ static __be32 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, int nfserr, struct nfsd4_sequence *seq) { - /* stub */ - return nfserr; + ENCODE_HEAD; + + if (nfserr) + return nfserr; + + RESERVE_SPACE(NFS4_MAX_SESSIONID_LEN + 20); + WRITEMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN); + WRITE32(seq->seqid); + WRITE32(seq->slotid); + WRITE32(seq->maxslots); + /* + * FIXME: for now: + * target_maxslots = maxslots + * status_flags = 0 + */ + WRITE32(seq->maxslots); + WRITE32(0); + + ADJUST_ARGS(); + return 0; } static __be32 diff --git a/include/linux/nfsd/xdr4.h b/include/linux/nfsd/xdr4.h index 33ee71e988b4..6e28a041008d 100644 --- a/include/linux/nfsd/xdr4.h +++ b/include/linux/nfsd/xdr4.h @@ -48,6 +48,9 @@ struct nfsd4_compound_state { struct svc_fh current_fh; struct svc_fh save_fh; struct nfs4_stateowner *replay_owner; + /* For sessions DRC */ + struct nfsd4_session *session; + struct nfsd4_slot *slot; }; struct nfsd4_change_info { @@ -358,7 +361,15 @@ struct nfsd4_create_session { }; struct nfsd4_sequence { - int foo; /* stub */ + struct nfs4_sessionid sessionid; /* request/response */ + u32 seqid; /* request/response */ + u32 slotid; /* request/response */ + u32 maxslots; /* request/response */ + u32 cachethis; /* request */ +#if 0 + u32 target_maxslots; /* response */ + u32 status_flags; /* response */ +#endif /* not yet */ }; struct nfsd4_destroy_session {