From bf864a31d50e3e94d6e76537b97d664913906ff8 Mon Sep 17 00:00:00 2001 From: Andy Adamson Date: Fri, 3 Apr 2009 08:28:35 +0300 Subject: [PATCH] nfsd41: non-page DRC for solo sequence responses 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 Signed-off-by: Benny Halevy [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 [changed return type to bool] Signed-off-by: Benny Halevy [nfsd41 drop parens in nfsd4_is_solo_sequence call] Signed-off-by: Andy Adamson [changed "== 0" to "!"] Signed-off-by: Benny Halevy Signed-off-by: J. Bruce Fields --- fs/nfsd/nfs4proc.c | 34 +++++++++++++++++++++++++++++++-- fs/nfsd/nfs4state.c | 47 ++++++++++++++++++++++++++++++++++++++++------ fs/nfsd/nfs4xdr.c | 5 +++-- include/linux/nfsd/state.h | 1 + include/linux/nfsd/xdr4.h | 15 ++++++++++++++- 5 files changed, 91 insertions(+), 11 deletions(-) diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index 9e2ee75..ae21a4e 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -828,6 +828,34 @@ static struct nfsd4_operation nfsd4_ops[]; static const char *nfsd4_op_name(unsigned opnum); /* + * This is a replay of a compound for which no cache entry pages + * were used. Encode the sequence operation, and if cachethis is FALSE + * encode the uncache rep error on the next operation. + */ +static __be32 +nfsd4_enc_uncached_replay(struct nfsd4_compoundargs *args, + struct nfsd4_compoundres *resp) +{ + struct nfsd4_op *op; + + dprintk("--> %s resp->opcnt %d ce_cachethis %u \n", __func__, + resp->opcnt, resp->cstate.slot->sl_cache_entry.ce_cachethis); + + /* Encode the replayed sequence operation */ + BUG_ON(resp->opcnt != 1); + op = &args->ops[resp->opcnt - 1]; + nfsd4_encode_operation(resp, op); + + /*return nfserr_retry_uncached_rep in next operation. */ + if (resp->cstate.slot->sl_cache_entry.ce_cachethis == 0) { + op = &args->ops[resp->opcnt++]; + op->status = nfserr_retry_uncached_rep; + nfsd4_encode_operation(resp, op); + } + return op->status; +} + +/* * Enforce NFSv4.1 COMPOUND ordering rules. * * TODO: @@ -895,7 +923,6 @@ nfsd4_proc_compound(struct svc_rqst *rqstp, dprintk("nfsv4 compound op #%d/%d: %d (%s)\n", resp->opcnt, args->opcnt, op->opnum, nfsd4_op_name(op->opnum)); - /* * The XDR decode routines may have pre-set op->status; * for example, if there is a miscellaneous XDR error @@ -939,7 +966,10 @@ encode_op: /* Only from SEQUENCE or CREATE_SESSION */ if (resp->cstate.status == nfserr_replay_cache) { dprintk("%s NFS4.1 replay from cache\n", __func__); - status = op->status; + if (nfsd4_not_cached(resp)) + status = nfsd4_enc_uncached_replay(args, resp); + else + status = op->status; goto out; } if (op->status == nfserr_replay_me) { diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 58f9797..04a395f 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -1049,17 +1049,31 @@ nfsd4_store_cache_entry(struct nfsd4_compoundres *resp) /* Don't cache a failed OP_SEQUENCE. */ if (resp->opcnt == 1 && op->opnum == OP_SEQUENCE && resp->cstate.status) return; + nfsd4_release_respages(entry->ce_respages, entry->ce_resused); + entry->ce_opcnt = resp->opcnt; + entry->ce_status = resp->cstate.status; + + /* + * Don't need a page to cache just the sequence operation - the slot + * does this for us! + */ + + if (nfsd4_not_cached(resp)) { + entry->ce_resused = 0; + entry->ce_rpchdrlen = 0; + dprintk("%s Just cache SEQUENCE. ce_cachethis %d\n", __func__, + resp->cstate.slot->sl_cache_entry.ce_cachethis); + return; + } entry->ce_resused = rqstp->rq_resused; if (entry->ce_resused > NFSD_PAGES_PER_SLOT + 1) entry->ce_resused = NFSD_PAGES_PER_SLOT + 1; nfsd4_copy_pages(entry->ce_respages, rqstp->rq_respages, entry->ce_resused); - entry->ce_status = resp->cstate.status; entry->ce_datav.iov_base = resp->cstate.statp; entry->ce_datav.iov_len = resv->iov_len - ((char *)resp->cstate.statp - (char *)page_address(rqstp->rq_respages[0])); - entry->ce_opcnt = resp->opcnt; /* Current request rpc header length*/ entry->ce_rpchdrlen = (char *)resp->cstate.statp - (char *)page_address(rqstp->rq_respages[0]); @@ -1096,13 +1110,28 @@ nfsd41_copy_replay_data(struct nfsd4_compoundres *resp, * cached page. Replace any futher replay pages from the cache. */ __be32 -nfsd4_replay_cache_entry(struct nfsd4_compoundres *resp) +nfsd4_replay_cache_entry(struct nfsd4_compoundres *resp, + struct nfsd4_sequence *seq) { struct nfsd4_cache_entry *entry = &resp->cstate.slot->sl_cache_entry; __be32 status; dprintk("--> %s entry %p\n", __func__, entry); + /* + * If this is just the sequence operation, we did not keep + * a page in the cache entry because we can just use the + * slot info stored in struct nfsd4_sequence that was checked + * against the slot in nfsd4_sequence(). + * + * This occurs when seq->cachethis is FALSE, or when the client + * session inactivity timer fires and a solo sequence operation + * is sent (lease renewal). + */ + if (seq && nfsd4_not_cached(resp)) { + seq->maxslots = resp->cstate.session->se_fnumslots; + return nfs_ok; + } if (!nfsd41_copy_replay_data(resp, entry)) { /* @@ -1330,7 +1359,7 @@ nfsd4_create_session(struct svc_rqst *rqstp, cstate->slot = slot; cstate->status = status; /* Return the cached reply status */ - status = nfsd4_replay_cache_entry(resp); + status = nfsd4_replay_cache_entry(resp, NULL); goto out; } else if (cr_ses->seqid != conf->cl_slot.sl_seqid + 1) { status = nfserr_seq_misordered; @@ -1380,6 +1409,8 @@ nfsd4_create_session(struct svc_rqst *rqstp, slot->sl_inuse = true; cstate->slot = slot; + /* Ensure a page is used for the cache */ + slot->sl_cache_entry.ce_cachethis = 1; out: nfs4_unlock_state(); dprintk("%s returns %d\n", __func__, ntohl(status)); @@ -1425,8 +1456,8 @@ nfsd4_sequence(struct svc_rqst *rqstp, cstate->slot = slot; cstate->session = session; /* Return the cached reply status and set cstate->status - * for nfsd4_svc_encode_compoundres processing*/ - status = nfsd4_replay_cache_entry(resp); + * for nfsd4_svc_encode_compoundres processing */ + status = nfsd4_replay_cache_entry(resp, seq); cstate->status = nfserr_replay_cache; goto replay_cache; } @@ -1436,6 +1467,10 @@ nfsd4_sequence(struct svc_rqst *rqstp, /* Success! bump slot seqid */ slot->sl_inuse = true; slot->sl_seqid = seq->seqid; + slot->sl_cache_entry.ce_cachethis = seq->cachethis; + /* Always set the cache entry cachethis for solo sequence */ + if (nfsd4_is_solo_sequence(resp)) + slot->sl_cache_entry.ce_cachethis = 1; cstate->slot = slot; cstate->session = session; diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 671f9b9..64bc215 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -2975,7 +2975,7 @@ nfsd4_encode_destroy_session(struct nfsd4_compoundres *resp, int nfserr, return nfserr; } -static __be32 +__be32 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, int nfserr, struct nfsd4_sequence *seq) { @@ -3192,7 +3192,8 @@ nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compo iov->iov_len = ((char*)resp->p) - (char*)iov->iov_base; BUG_ON(iov->iov_len > PAGE_SIZE); if (resp->cstate.slot != NULL) { - if (resp->cstate.status == nfserr_replay_cache) { + if (resp->cstate.status == nfserr_replay_cache && + !nfsd4_not_cached(resp)) { iov->iov_len = resp->cstate.iovlen; } else { nfsd4_store_cache_entry(resp); diff --git a/include/linux/nfsd/state.h b/include/linux/nfsd/state.h index f063df7..18dcffa 100644 --- a/include/linux/nfsd/state.h +++ b/include/linux/nfsd/state.h @@ -110,6 +110,7 @@ struct nfsd4_cache_entry { __be32 ce_status; struct kvec ce_datav; /* encoded NFSv4.1 data in rq_res.head[0] */ struct page *ce_respages[NFSD_PAGES_PER_SLOT + 1]; + int ce_cachethis; short ce_resused; int ce_opcnt; int ce_rpchdrlen; diff --git a/include/linux/nfsd/xdr4.h b/include/linux/nfsd/xdr4.h index 9468829..4861888 100644 --- a/include/linux/nfsd/xdr4.h +++ b/include/linux/nfsd/xdr4.h @@ -480,6 +480,18 @@ struct nfsd4_compoundres { struct nfsd4_compound_state cstate; }; +static inline bool nfsd4_is_solo_sequence(struct nfsd4_compoundres *resp) +{ + struct nfsd4_compoundargs *args = resp->rqstp->rq_argp; + return args->opcnt == 1; +} + +static inline bool nfsd4_not_cached(struct nfsd4_compoundres *resp) +{ + return !resp->cstate.slot->sl_cache_entry.ce_cachethis || + nfsd4_is_solo_sequence(resp); +} + #define NFS4_SVC_XDRSIZE sizeof(struct nfsd4_compoundargs) static inline void @@ -510,7 +522,8 @@ extern __be32 nfsd4_setclientid_confirm(struct svc_rqst *rqstp, struct nfsd4_compound_state *, struct nfsd4_setclientid_confirm *setclientid_confirm); extern void nfsd4_store_cache_entry(struct nfsd4_compoundres *resp); -extern __be32 nfsd4_replay_cache_entry(struct nfsd4_compoundres *resp); +extern __be32 nfsd4_replay_cache_entry(struct nfsd4_compoundres *resp, + struct nfsd4_sequence *seq); extern __be32 nfsd4_exchange_id(struct svc_rqst *rqstp, struct nfsd4_compound_state *, struct nfsd4_exchange_id *); -- 1.8.2.3