From: "J. Bruce Fields" Subject: Re: [PATCH v2 23/47] nfsd41: create_session operation Date: Tue, 31 Mar 2009 21:06:54 -0400 Message-ID: <20090401010654.GE26583@fieldses.org> References: <49CDDFC2.4070402@panasas.com> <1238229177-10984-1-git-send-email-bhalevy@panasas.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-nfs@vger.kernel.org, pnfs@linux-nfs.org To: Benny Halevy Return-path: Received: from mail.fieldses.org ([141.211.133.115]:53559 "EHLO pickle.fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762530AbZDABG4 (ORCPT ); Tue, 31 Mar 2009 21:06:56 -0400 In-Reply-To: <1238229177-10984-1-git-send-email-bhalevy@panasas.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Sat, Mar 28, 2009 at 11:32:57AM +0300, Benny Halevy wrote: > From: Andy Adamson > > 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 > Signed-off-by: Dean Hildebrand > [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 > Signed-off-by: Benny Halevy > [use sessionid_lock spin lock] > [nfsd41: use bool inuse for slot state] > Signed-off-by: Benny Halevy > --- > fs/nfsd/nfs4state.c | 197 +++++++++++++++++++++++++++++++++++++++++++- > fs/nfsd/nfs4xdr.c | 147 ++++++++++++++++++++++++++++++++- > include/linux/nfsd/state.h | 7 ++ > include/linux/nfsd/xdr4.h | 21 +++++- > 4 files changed, 368 insertions(+), 4 deletions(-) > > diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c > index 37865c9..e4e2c19 100644 > --- a/fs/nfsd/nfs4state.c > +++ b/fs/nfsd/nfs4state.c > @@ -68,6 +68,9 @@ static u32 current_delegid = 1; > static u32 nfs4_init; > static stateid_t zerostateid; /* bits all 0 */ > static stateid_t onestateid; /* bits all 1 */ > +#ifdef CONFIG_NFSD_V4_1 > +static u64 current_sessionid = 1; > +#endif /* CONFIG_NFSD_V4_1 */ > > #define ZERO_STATEID(stateid) (!memcmp((stateid), &zerostateid, sizeof(stateid_t))) > #define ONE_STATEID(stateid) (!memcmp((stateid), &onestateid, sizeof(stateid_t))) > @@ -402,6 +405,138 @@ dump_sessionid(const char *fn, struct nfs4_sessionid *sessionid) > dprintk("%s: %u:%u:%u:%u\n", fn, ptr[0], ptr[1], ptr[2], ptr[3]); > } > > +static void > +gen_sessionid(struct nfsd4_session *ses) > +{ > + struct nfs4_client *clp = ses->se_client; > + struct nfsd4_sessionid *sid; > + > + sid = (struct nfsd4_sessionid *)ses->se_sessionid.data; > + sid->clientid = clp->cl_clientid; > + sid->sequence = current_sessionid++; > + sid->reserved = 0; > +} > + > +/* > + * Give the client the number of slots it requests bound by > + * NFSD_MAX_SLOTS_PER_SESSION and by sv_drc_max_pages. > + * > + * If we run out of pages (sv_drc_pages_used == sv_drc_max_pages) we > + * should (up to a point) re-negotiate active sessions and reduce their > + * slot usage to make rooom for new connections. For now we just fail the > + * create session. > + */ > +static int set_forechannel_maxreqs(struct nfsd4_channel_attrs *fchan) > +{ > + int status = 0, np = fchan->maxreqs * NFSD_PAGES_PER_SLOT; > + > + spin_lock(&nfsd_serv->sv_lock); > + if (np + nfsd_serv->sv_drc_pages_used > nfsd_serv->sv_drc_max_pages) > + np = nfsd_serv->sv_drc_max_pages - nfsd_serv->sv_drc_pages_used; > + nfsd_serv->sv_drc_pages_used += np; > + spin_unlock(&nfsd_serv->sv_lock); > + > + if (np <= 0) { > + status = nfserr_resource; > + fchan->maxreqs = 0; > + } else > + fchan->maxreqs = np / NFSD_PAGES_PER_SLOT; > + > + return status; > +} > + > +/* > + * fchan holds the client values on input, and the server values on output > + */ > +static int init_forechannel_attrs(struct svc_rqst *rqstp, > + struct nfsd4_session *session, > + struct nfsd4_channel_attrs *fchan) > +{ > + int status = 0; > + __u32 maxcount = svc_max_payload(rqstp); > + > + /* headerpadsz set to zero in encode routine*/ > + > + /* Use the client's max request and max response size if possible */ > + if (fchan->maxreq_sz > maxcount) > + fchan->maxreq_sz = maxcount; > + session->se_fmaxreq_sz = fchan->maxreq_sz; > + > + if (fchan->maxresp_sz > maxcount) > + fchan->maxresp_sz = maxcount; > + session->se_fmaxresp_sz = fchan->maxresp_sz; > + > + /* Set the max response cached size our default which is > + * a multiple of PAGE_SIZE and small */ > + session->se_fmaxresp_cached = NFSD_PAGES_PER_SLOT * PAGE_SIZE; > + fchan->maxresp_cached = session->se_fmaxresp_cached; > + > + /* Use the client's maxops if possible */ > + if (fchan->maxops > NFSD_MAX_OPS_PER_COMPOUND) > + fchan->maxops = NFSD_MAX_OPS_PER_COMPOUND; > + session->se_fmaxops = fchan->maxops; > + > + /* try to use the client requested number of slots */ > + if (fchan->maxreqs > NFSD_MAX_SLOTS_PER_SESSION) > + fchan->maxreqs = NFSD_MAX_SLOTS_PER_SESSION; > + > + /* FIXME: Error means no more DRC pages so the server should > + * recover pages from existing sessions. For now fail session > + * creation. > + */ > + status = set_forechannel_maxreqs(fchan); > + > + session->se_fnumslots = fchan->maxreqs; > + return status; > +} > + > +static int > +alloc_init_session(struct svc_rqst *rqstp, struct nfs4_client *clp, > + struct nfsd4_create_session *cses) > +{ > + struct nfsd4_session *new; > + int idx, status = nfserr_resource, slotsize, i; > + > + new = kzalloc(sizeof(*new), GFP_KERNEL); > + if (!new) > + goto out; > + > + /* FIXME: For now, we just accept the client back channel attributes. */ > + status = init_forechannel_attrs(rqstp, new, &cses->fore_channel); > + if (status) > + goto out_free; > + > + slotsize = new->se_fnumslots * sizeof(struct nfsd4_slot); > + new->se_slots = kzalloc(slotsize, GFP_KERNEL); > + if (!new->se_slots) > + goto out_free; > + > + for (i = 0; i < new->se_fnumslots; i++) > + new->se_slots[i].sl_session = new; > + > + new->se_client = clp; > + gen_sessionid(new); > + idx = hash_sessionid(&new->se_sessionid); > + memcpy(clp->cl_sessionid.data, new->se_sessionid.data, > + NFS4_MAX_SESSIONID_LEN); The sessionid should be part of the new session, not the client, right? > + > + new->se_flags = cses->flags; > + kref_init(&new->se_ref); > + INIT_LIST_HEAD(&new->se_hash); > + INIT_LIST_HEAD(&new->se_perclnt); > + spin_lock(&sessionid_lock); > + list_add(&new->se_hash, &sessionid_hashtbl[idx]); > + list_add(&new->se_perclnt, &clp->cl_sessions); > + spin_unlock(&sessionid_lock); > + > + status = nfs_ok; > +out: > + return status; > +out_free: > + kfree(new); > + goto out; > +} > + > /* caller must hold sessionid_lock */ > static struct nfsd4_session * > find_in_sessionid_hashtbl(struct nfs4_sessionid *sessionid) > @@ -1186,7 +1321,67 @@ nfsd4_create_session(struct svc_rqst *rqstp, > struct nfsd4_compound_state *cstate, > struct nfsd4_create_session *cr_ses) > { > - return -1; /* stub */ > + u32 ip_addr = svc_addr_in(rqstp)->sin_addr.s_addr; > + struct nfs4_client *conf, *unconf; > + int status = 0; > + > + nfs4_lock_state(); > + unconf = find_unconfirmed_client(&cr_ses->clientid); > + conf = find_confirmed_client(&cr_ses->clientid); > + > + if (conf) { > + status = nfs_ok; > + if (conf->cl_seqid == cr_ses->seqid) { > + dprintk("Got a create_session replay! seqid= %d\n", > + conf->cl_seqid); > + goto out_replay; > + } else if (cr_ses->seqid != conf->cl_seqid + 1) { > + status = nfserr_seq_misordered; > + dprintk("Sequence misordered!\n"); > + dprintk("Expected seqid= %d but got seqid= %d\n", > + conf->cl_seqid, cr_ses->seqid); > + goto out; > + } > + conf->cl_seqid++; > + } else if (unconf) { > + if (!same_creds(&unconf->cl_cred, &rqstp->rq_cred) || > + (ip_addr != unconf->cl_addr)) { Again, I don't believe the nfsv4/4.1 specs require the client to keep to a single ip address, so we shouldn't be doing ip address checks. --b. > + status = nfserr_clid_inuse; > + goto out; > + } > + > + if (unconf->cl_seqid != cr_ses->seqid) { > + status = nfserr_seq_misordered; > + goto out; > + } > + > + move_to_confirmed(unconf); > + > + /* > + * We do not support RDMA or persistent sessions > + */ > + cr_ses->flags &= ~SESSION4_PERSIST; > + cr_ses->flags &= ~SESSION4_RDMA; > + > + conf = unconf; > + } else { > + status = nfserr_stale_clientid; > + goto out; Is this the right error? --b. > + } > + > + status = alloc_init_session(rqstp, conf, cr_ses); > + if (status) > + goto out; > + > +out_replay: > + memcpy(cr_ses->sessionid.data, conf->cl_sessionid.data, > + NFS4_MAX_SESSIONID_LEN); > + cr_ses->seqid = conf->cl_seqid; > + > +out: > + nfs4_unlock_state(); > + dprintk("%s returns %d\n", __func__, ntohl(status)); > + return status; > } > > __be32 > diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c > index 57afb33..60db854 100644 > --- a/fs/nfsd/nfs4xdr.c > +++ b/fs/nfsd/nfs4xdr.c > @@ -1100,7 +1100,108 @@ static __be32 > nfsd4_decode_create_session(struct nfsd4_compoundargs *argp, > struct nfsd4_create_session *sess) > { > - return nfserr_opnotsupp; /* stub */ > + DECODE_HEAD; > + > + u32 dummy; > + char *machine_name; > + int i; > + int nr_secflavs; > + > + READ_BUF(16); > + COPYMEM(&sess->clientid, 8); > + READ32(sess->seqid); > + READ32(sess->flags); > + > + /* Fore channel attrs */ > + READ_BUF(28); > + READ32(dummy); /* headerpadsz is always 0 */ > + READ32(sess->fore_channel.maxreq_sz); > + READ32(sess->fore_channel.maxresp_sz); > + READ32(sess->fore_channel.maxresp_cached); > + READ32(sess->fore_channel.maxops); > + READ32(sess->fore_channel.maxreqs); > + READ32(sess->fore_channel.nr_rdma_attrs); > + if (sess->fore_channel.nr_rdma_attrs == 1) { > + READ_BUF(4); > + READ32(sess->fore_channel.rdma_attrs); > + } else if (sess->fore_channel.nr_rdma_attrs > 1) { > + dprintk("Too many fore channel attr bitmaps!\n"); > + goto xdr_error; > + } > + > + /* Back channel attrs */ > + READ_BUF(28); > + READ32(dummy); /* headerpadsz is always 0 */ > + READ32(sess->back_channel.maxreq_sz); > + READ32(sess->back_channel.maxresp_sz); > + READ32(sess->back_channel.maxresp_cached); > + READ32(sess->back_channel.maxops); > + READ32(sess->back_channel.maxreqs); > + READ32(sess->back_channel.nr_rdma_attrs); > + if (sess->back_channel.nr_rdma_attrs == 1) { > + READ_BUF(4); > + READ32(sess->back_channel.rdma_attrs); > + } else if (sess->back_channel.nr_rdma_attrs > 1) { > + dprintk("Too many back channel attr bitmaps!\n"); > + goto xdr_error; > + } > + > + READ_BUF(8); > + READ32(sess->callback_prog); > + > + /* callback_sec_params4 */ > + READ32(nr_secflavs); > + for (i = 0; i < nr_secflavs; ++i) { > + READ_BUF(4); > + READ32(dummy); > + switch (dummy) { > + case RPC_AUTH_NULL: > + /* Nothing to read */ > + break; > + case RPC_AUTH_UNIX: > + READ_BUF(8); > + /* stamp */ > + READ32(dummy); > + > + /* machine name */ > + READ32(dummy); > + READ_BUF(dummy); > + SAVEMEM(machine_name, dummy); > + > + /* uid, gid */ > + READ_BUF(8); > + READ32(sess->uid); > + READ32(sess->gid); > + > + /* more gids */ > + READ_BUF(4); > + READ32(dummy); > + READ_BUF(dummy * 4); > + for (i = 0; i < dummy; ++i) > + READ32(dummy); > + break; > + case RPC_AUTH_GSS: > + dprintk("RPC_AUTH_GSS callback secflavor " > + "not supported!\n"); > + READ_BUF(8); > + /* gcbp_service */ > + READ32(dummy); > + /* gcbp_handle_from_server */ > + READ32(dummy); > + READ_BUF(dummy); > + p += XDR_QUADLEN(dummy); > + /* gcbp_handle_from_client */ > + READ_BUF(4); > + READ32(dummy); > + READ_BUF(dummy); > + p += XDR_QUADLEN(dummy); > + break; > + default: > + dprintk("Illegal callback secflavor\n"); > + return nfserr_inval; > + } > + } > + DECODE_TAIL; > } > > static __be32 > @@ -2829,7 +2930,49 @@ static __be32 > nfsd4_encode_create_session(struct nfsd4_compoundres *resp, int nfserr, > struct nfsd4_create_session *sess) > { > - /* stub */ > + ENCODE_HEAD; > + > + if (nfserr) > + goto out; > + > + RESERVE_SPACE(24); > + WRITEMEM(sess->sessionid.data, NFS4_MAX_SESSIONID_LEN); > + WRITE32(sess->seqid); > + WRITE32(sess->flags); > + ADJUST_ARGS(); > + > + RESERVE_SPACE(28); > + WRITE32(0); /* headerpadsz */ > + WRITE32(sess->fore_channel.maxreq_sz); > + WRITE32(sess->fore_channel.maxresp_sz); > + WRITE32(sess->fore_channel.maxresp_cached); > + WRITE32(sess->fore_channel.maxops); > + WRITE32(sess->fore_channel.maxreqs); > + WRITE32(sess->fore_channel.nr_rdma_attrs); > + ADJUST_ARGS(); > + > + if (sess->fore_channel.nr_rdma_attrs) { > + RESERVE_SPACE(4); > + WRITE32(sess->fore_channel.rdma_attrs); > + ADJUST_ARGS(); > + } > + > + RESERVE_SPACE(28); > + WRITE32(0); /* headerpadsz */ > + WRITE32(sess->back_channel.maxreq_sz); > + WRITE32(sess->back_channel.maxresp_sz); > + WRITE32(sess->back_channel.maxresp_cached); > + WRITE32(sess->back_channel.maxops); > + WRITE32(sess->back_channel.maxreqs); > + WRITE32(sess->back_channel.nr_rdma_attrs); > + ADJUST_ARGS(); > + > + if (sess->back_channel.nr_rdma_attrs) { > + RESERVE_SPACE(4); > + WRITE32(sess->back_channel.rdma_attrs); > + ADJUST_ARGS(); > + } > +out: > return nfserr; > } > > diff --git a/include/linux/nfsd/state.h b/include/linux/nfsd/state.h > index 8ca6a82..98d7b1c 100644 > --- a/include/linux/nfsd/state.h > +++ b/include/linux/nfsd/state.h > @@ -99,8 +99,12 @@ struct nfs4_callback { > struct rpc_clnt * cb_client; > }; > > +/* Maximum number of slots per session. 128 is useful for long haul TCP */ > +#define NFSD_MAX_SLOTS_PER_SESSION 128 > /* Maximum number of pages per slot cache entry */ > #define NFSD_PAGES_PER_SLOT 1 > +/* Maximum number of operations per session compound */ > +#define NFSD_MAX_OPS_PER_COMPOUND 16 > > struct nfsd4_cache_entry { > __be32 ce_status; > @@ -188,6 +192,9 @@ struct nfs4_client { > struct list_head cl_sessions; > u32 cl_seqid; /* seqid for create_session */ > u32 cl_exchange_flags; > + struct nfs4_sessionid cl_sessionid; > + > + struct svc_xprt *cl_cb_xprt; /* 4.1 callback transport */ > #endif /* CONFIG_NFSD_V4_1 */ > }; > > diff --git a/include/linux/nfsd/xdr4.h b/include/linux/nfsd/xdr4.h > index 5c0d376..c7bf0a1 100644 > --- a/include/linux/nfsd/xdr4.h > +++ b/include/linux/nfsd/xdr4.h > @@ -360,8 +360,27 @@ struct nfsd4_exchange_id { > int spa_how; > }; > > +struct nfsd4_channel_attrs { > + u32 headerpadsz; > + u32 maxreq_sz; > + u32 maxresp_sz; > + u32 maxresp_cached; > + u32 maxops; > + u32 maxreqs; > + u32 nr_rdma_attrs; > + u32 rdma_attrs; > +}; > + > struct nfsd4_create_session { > - int foo; /* stub */ > + clientid_t clientid; > + struct nfs4_sessionid sessionid; > + u32 seqid; > + u32 flags; > + struct nfsd4_channel_attrs fore_channel; > + struct nfsd4_channel_attrs back_channel; > + u32 callback_prog; > + u32 uid; > + u32 gid; > }; > > struct nfsd4_sequence { > -- > 1.6.2.1 >