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authorAndy Adamson <andros@netapp.com>2009-04-03 01:28:28 -0400
committerJ. Bruce Fields <bfields@citi.umich.edu>2009-04-03 20:41:18 -0400
commitec6b5d7b5064fde27aee798b81107ea3a830de85 (patch)
treede1571b6773201268796fe5bf3db9bb0f8d23812 /fs/nfsd/nfs4state.c
parent14778a133e3be332be77d981552a79260a61ee17 (diff)
nfsd41: create_session operation
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>
Diffstat (limited to 'fs/nfsd/nfs4state.c')
-rw-r--r--fs/nfsd/nfs4state.c188
1 files changed, 187 insertions, 1 deletions
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index f25a7d2a9fac..463ae39df148 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -68,6 +68,7 @@ static u32 current_delegid = 1;
68static u32 nfs4_init; 68static u32 nfs4_init;
69static stateid_t zerostateid; /* bits all 0 */ 69static stateid_t zerostateid; /* bits all 0 */
70static stateid_t onestateid; /* bits all 1 */ 70static stateid_t onestateid; /* bits all 1 */
71static u64 current_sessionid = 1;
71 72
72#define ZERO_STATEID(stateid) (!memcmp((stateid), &zerostateid, sizeof(stateid_t))) 73#define ZERO_STATEID(stateid) (!memcmp((stateid), &zerostateid, sizeof(stateid_t)))
73#define ONE_STATEID(stateid) (!memcmp((stateid), &onestateid, sizeof(stateid_t))) 74#define ONE_STATEID(stateid) (!memcmp((stateid), &onestateid, sizeof(stateid_t)))
@@ -401,6 +402,131 @@ dump_sessionid(const char *fn, struct nfs4_sessionid *sessionid)
401 dprintk("%s: %u:%u:%u:%u\n", fn, ptr[0], ptr[1], ptr[2], ptr[3]); 402 dprintk("%s: %u:%u:%u:%u\n", fn, ptr[0], ptr[1], ptr[2], ptr[3]);
402} 403}
403 404
405static void
406gen_sessionid(struct nfsd4_session *ses)
407{
408 struct nfs4_client *clp = ses->se_client;
409 struct nfsd4_sessionid *sid;
410
411 sid = (struct nfsd4_sessionid *)ses->se_sessionid.data;
412 sid->clientid = clp->cl_clientid;
413 sid->sequence = current_sessionid++;
414 sid->reserved = 0;
415}
416
417/*
418 * Give the client the number of slots it requests bound by
419 * NFSD_MAX_SLOTS_PER_SESSION and by sv_drc_max_pages.
420 *
421 * If we run out of pages (sv_drc_pages_used == sv_drc_max_pages) we
422 * should (up to a point) re-negotiate active sessions and reduce their
423 * slot usage to make rooom for new connections. For now we just fail the
424 * create session.
425 */
426static int set_forechannel_maxreqs(struct nfsd4_channel_attrs *fchan)
427{
428 int status = 0, np = fchan->maxreqs * NFSD_PAGES_PER_SLOT;
429
430 spin_lock(&nfsd_serv->sv_lock);
431 if (np + nfsd_serv->sv_drc_pages_used > nfsd_serv->sv_drc_max_pages)
432 np = nfsd_serv->sv_drc_max_pages - nfsd_serv->sv_drc_pages_used;
433 nfsd_serv->sv_drc_pages_used += np;
434 spin_unlock(&nfsd_serv->sv_lock);
435
436 if (np <= 0) {
437 status = nfserr_resource;
438 fchan->maxreqs = 0;
439 } else
440 fchan->maxreqs = np / NFSD_PAGES_PER_SLOT;
441
442 return status;
443}
444
445/*
446 * fchan holds the client values on input, and the server values on output
447 */
448static int init_forechannel_attrs(struct svc_rqst *rqstp,
449 struct nfsd4_session *session,
450 struct nfsd4_channel_attrs *fchan)
451{
452 int status = 0;
453 __u32 maxcount = svc_max_payload(rqstp);
454
455 /* headerpadsz set to zero in encode routine */
456
457 /* Use the client's max request and max response size if possible */
458 if (fchan->maxreq_sz > maxcount)
459 fchan->maxreq_sz = maxcount;
460 session->se_fmaxreq_sz = fchan->maxreq_sz;
461
462 if (fchan->maxresp_sz > maxcount)
463 fchan->maxresp_sz = maxcount;
464 session->se_fmaxresp_sz = fchan->maxresp_sz;
465
466 /* Set the max response cached size our default which is
467 * a multiple of PAGE_SIZE and small */
468 session->se_fmaxresp_cached = NFSD_PAGES_PER_SLOT * PAGE_SIZE;
469 fchan->maxresp_cached = session->se_fmaxresp_cached;
470
471 /* Use the client's maxops if possible */
472 if (fchan->maxops > NFSD_MAX_OPS_PER_COMPOUND)
473 fchan->maxops = NFSD_MAX_OPS_PER_COMPOUND;
474 session->se_fmaxops = fchan->maxops;
475
476 /* try to use the client requested number of slots */
477 if (fchan->maxreqs > NFSD_MAX_SLOTS_PER_SESSION)
478 fchan->maxreqs = NFSD_MAX_SLOTS_PER_SESSION;
479
480 /* FIXME: Error means no more DRC pages so the server should
481 * recover pages from existing sessions. For now fail session
482 * creation.
483 */
484 status = set_forechannel_maxreqs(fchan);
485
486 session->se_fnumslots = fchan->maxreqs;
487 return status;
488}
489
490static int
491alloc_init_session(struct svc_rqst *rqstp, struct nfs4_client *clp,
492 struct nfsd4_create_session *cses)
493{
494 struct nfsd4_session *new, tmp;
495 int idx, status = nfserr_resource, slotsize;
496
497 memset(&tmp, 0, sizeof(tmp));
498
499 /* FIXME: For now, we just accept the client back channel attributes. */
500 status = init_forechannel_attrs(rqstp, &tmp, &cses->fore_channel);
501 if (status)
502 goto out;
503
504 /* allocate struct nfsd4_session and slot table in one piece */
505 slotsize = tmp.se_fnumslots * sizeof(struct nfsd4_slot);
506 new = kzalloc(sizeof(*new) + slotsize, GFP_KERNEL);
507 if (!new)
508 goto out;
509
510 memcpy(new, &tmp, sizeof(*new));
511
512 new->se_client = clp;
513 gen_sessionid(new);
514 idx = hash_sessionid(&new->se_sessionid);
515 memcpy(clp->cl_sessionid.data, new->se_sessionid.data,
516 NFS4_MAX_SESSIONID_LEN);
517
518 new->se_flags = cses->flags;
519 kref_init(&new->se_ref);
520 spin_lock(&sessionid_lock);
521 list_add(&new->se_hash, &sessionid_hashtbl[idx]);
522 list_add(&new->se_perclnt, &clp->cl_sessions);
523 spin_unlock(&sessionid_lock);
524
525 status = nfs_ok;
526out:
527 return status;
528}
529
404/* caller must hold sessionid_lock */ 530/* caller must hold sessionid_lock */
405static struct nfsd4_session * 531static struct nfsd4_session *
406find_in_sessionid_hashtbl(struct nfs4_sessionid *sessionid) 532find_in_sessionid_hashtbl(struct nfs4_sessionid *sessionid)
@@ -1182,7 +1308,67 @@ nfsd4_create_session(struct svc_rqst *rqstp,
1182 struct nfsd4_compound_state *cstate, 1308 struct nfsd4_compound_state *cstate,
1183 struct nfsd4_create_session *cr_ses) 1309 struct nfsd4_create_session *cr_ses)
1184{ 1310{
1185 return -1; /* stub */ 1311 u32 ip_addr = svc_addr_in(rqstp)->sin_addr.s_addr;
1312 struct nfs4_client *conf, *unconf;
1313 int status = 0;
1314
1315 nfs4_lock_state();
1316 unconf = find_unconfirmed_client(&cr_ses->clientid);
1317 conf = find_confirmed_client(&cr_ses->clientid);
1318
1319 if (conf) {
1320 status = nfs_ok;
1321 if (conf->cl_seqid == cr_ses->seqid) {
1322 dprintk("Got a create_session replay! seqid= %d\n",
1323 conf->cl_seqid);
1324 goto out_replay;
1325 } else if (cr_ses->seqid != conf->cl_seqid + 1) {
1326 status = nfserr_seq_misordered;
1327 dprintk("Sequence misordered!\n");
1328 dprintk("Expected seqid= %d but got seqid= %d\n",
1329 conf->cl_seqid, cr_ses->seqid);
1330 goto out;
1331 }
1332 conf->cl_seqid++;
1333 } else if (unconf) {
1334 if (!same_creds(&unconf->cl_cred, &rqstp->rq_cred) ||
1335 (ip_addr != unconf->cl_addr)) {
1336 status = nfserr_clid_inuse;
1337 goto out;
1338 }
1339
1340 if (unconf->cl_seqid != cr_ses->seqid) {
1341 status = nfserr_seq_misordered;
1342 goto out;
1343 }
1344
1345 move_to_confirmed(unconf);
1346
1347 /*
1348 * We do not support RDMA or persistent sessions
1349 */
1350 cr_ses->flags &= ~SESSION4_PERSIST;
1351 cr_ses->flags &= ~SESSION4_RDMA;
1352
1353 conf = unconf;
1354 } else {
1355 status = nfserr_stale_clientid;
1356 goto out;
1357 }
1358
1359 status = alloc_init_session(rqstp, conf, cr_ses);
1360 if (status)
1361 goto out;
1362
1363out_replay:
1364 memcpy(cr_ses->sessionid.data, conf->cl_sessionid.data,
1365 NFS4_MAX_SESSIONID_LEN);
1366 cr_ses->seqid = conf->cl_seqid;
1367
1368out:
1369 nfs4_unlock_state();
1370 dprintk("%s returns %d\n", __func__, ntohl(status));
1371 return status;
1186} 1372}
1187 1373
1188__be32 1374__be32