--- servers/slapd/overlays/syncprov.c	2009/03/13 02:44:51	1.272
+++ servers/slapd/overlays/syncprov.c	2009/11/14 20:53:06	1.296
@@ -1,4 +1,4 @@
-/* $OpenLDAP: pkg/ldap/servers/slapd/overlays/syncprov.c,v 1.271 2009/03/13 00:07:45 hyc Exp $ */
+/* $OpenLDAP: pkg/ldap/servers/slapd/overlays/syncprov.c,v 1.295 2009/11/14 08:35:23 hyc Exp $ */
 /* syncprov.c - syncrepl provider */
 /* This work is part of OpenLDAP Software <http://www.openldap.org/>.
  *
@@ -124,6 +124,7 @@ typedef struct sessionlog {
 typedef struct syncprov_info_t {
 	syncops		*si_ops;
 	BerVarray	si_ctxcsn;	/* ldapsync context */
+	struct berval	si_contextdn;
 	int		*si_sids;
 	int		si_numcsns;
 	int		si_chkops;	/* checkpointing info */
@@ -137,16 +138,19 @@ typedef struct syncprov_info_t {
 	ldap_pvt_thread_rdwr_t	si_csn_rwlock;
 	ldap_pvt_thread_mutex_t	si_ops_mutex;
 	ldap_pvt_thread_mutex_t	si_mods_mutex;
+	ldap_pvt_thread_mutex_t	si_resp_mutex;
 } syncprov_info_t;
 
 typedef struct opcookie {
 	slap_overinst *son;
 	syncmatches *smatches;
+	modtarget *smt;
 	struct berval sdn;	/* DN of entry, for deletes */
 	struct berval sndn;
 	struct berval suuid;	/* UUID of entry */
 	struct berval sctxcsn;
-	short ssid;	/* sid of op csn */
+	short osid;	/* sid of op csn */
+	short rsid;	/* sid of relay */
 	short sreference;	/* Is the entry a reference? */
 } opcookie;
 
@@ -580,8 +584,8 @@ syncprov_findcsn( Operation *op, find_cs
 	slap_callback cb = {0};
 	Operation fop;
 	SlapReply frs = { REP_RESULT };
-	char buf[LDAP_LUTIL_CSNSTR_BUFSIZE + STRLENOF("(entryCSN<=)")];
-	char cbuf[LDAP_LUTIL_CSNSTR_BUFSIZE];
+	char buf[LDAP_PVT_CSNSTR_BUFSIZE + STRLENOF("(entryCSN<=)")];
+	char cbuf[LDAP_PVT_CSNSTR_BUFSIZE];
 	struct berval maxcsn;
 	Filter cf;
 	AttributeAssertion eq = ATTRIBUTEASSERTION_INIT;
@@ -773,7 +777,7 @@ syncprov_sendresp( Operation *op, opcook
 
 	SlapReply rs = { REP_SEARCH };
 	LDAPControl *ctrls[2];
-	struct berval cookie, csns[2];
+	struct berval cookie = BER_BVNULL, csns[2];
 	Entry e_uuid = {0};
 	Attribute a_uuid = {0};
 
@@ -781,18 +785,22 @@ syncprov_sendresp( Operation *op, opcook
 		return SLAPD_ABANDON;
 
 	ctrls[1] = NULL;
-	csns[0] = opc->sctxcsn;
-	BER_BVZERO( &csns[1] );
-	slap_compose_sync_cookie( op, &cookie, csns, so->s_rid, slap_serverID ? slap_serverID : -1 );
+	if ( !BER_BVISNULL( &opc->sctxcsn )) {
+		csns[0] = opc->sctxcsn;
+		BER_BVZERO( &csns[1] );
+		slap_compose_sync_cookie( op, &cookie, csns, so->s_rid, slap_serverID ? slap_serverID : -1 );
+	}
 
 #ifdef LDAP_DEBUG
-	if ( so->s_sid > 0 ) {
-		Debug( LDAP_DEBUG_SYNC, "syncprov_sendresp: to=%03x, cookie=%s\n",
-			so->s_sid, cookie.bv_val, 0 );
-	} else {
-		Debug( LDAP_DEBUG_SYNC, "syncprov_sendresp: cookie=%s\n",
-			cookie.bv_val, 0, 0 );
-	}
+	if ( !BER_BVISNULL( &cookie )) {
+		if ( so->s_sid > 0 ) {
+			Debug( LDAP_DEBUG_SYNC, "syncprov_sendresp: to=%03x, cookie=%s\n",
+				so->s_sid, cookie.bv_val , 0 );
+		} else {
+			Debug( LDAP_DEBUG_SYNC, "syncprov_sendresp: cookie=%s\n",
+				cookie.bv_val, 0, 0 );
+		}
+	}		
 #endif
 
 	e_uuid.e_attrs = &a_uuid;
@@ -800,7 +808,9 @@ syncprov_sendresp( Operation *op, opcook
 	a_uuid.a_nvals = &opc->suuid;
 	rs.sr_err = syncprov_state_ctrl( op, &rs, &e_uuid,
 		mode, ctrls, 0, 1, &cookie );
-	op->o_tmpfree( cookie.bv_val, op->o_tmpmemctx );
+	if ( !BER_BVISNULL( &cookie )) {
+		op->o_tmpfree( cookie.bv_val, op->o_tmpmemctx );
+	}
 
 	rs.sr_ctrls = ctrls;
 	op->o_bd->bd_info = (BackendInfo *)on->on_info;
@@ -845,7 +855,14 @@ syncprov_sendresp( Operation *op, opcook
 	}
 	/* In case someone else freed it already? */
 	if ( rs.sr_ctrls ) {
-		op->o_tmpfree( rs.sr_ctrls[0], op->o_tmpmemctx );
+		int i;
+		for ( i=0; rs.sr_ctrls[i]; i++ ) {
+			if ( rs.sr_ctrls[i] == ctrls[0] ) {
+				op->o_tmpfree( ctrls[0]->ldctl_value.bv_val, op->o_tmpmemctx );
+				ctrls[0]->ldctl_value.bv_val = NULL;
+				break;
+			}
+		}
 		rs.sr_ctrls = NULL;
 	}
 
@@ -1117,7 +1134,6 @@ syncprov_matchops( Operation *op, opcook
 
 	fbase_cookie fc;
 	syncops *ss, *sprev, *snext;
-	struct sync_cookie *scook;
 	Entry *e = NULL;
 	Attribute *a;
 	int rc;
@@ -1169,7 +1185,6 @@ syncprov_matchops( Operation *op, opcook
 		ber_dupbv_x( &opc->sndn, &e->e_nname, op->o_tmpmemctx );
 	}
 
-	scook = op->o_controls ? op->o_controls[slap_cids.sc_LDAPsync] : NULL;
 	ldap_pvt_thread_mutex_lock( &si->si_ops_mutex );
 	for (ss = si->si_ops, sprev = (syncops *)&si->si_ops; ss;
 		sprev = ss, ss=snext)
@@ -1183,18 +1198,22 @@ syncprov_matchops( Operation *op, opcook
 		if ( ss->s_op->o_abandon )
 			continue;
 
-		/* Don't send ops back to the originator */
-		if ( opc->ssid > 0 && opc->ssid == ss->s_sid ) {
-			Debug( LDAP_DEBUG_SYNC, "syncprov_matchops: skipping original sid %03x\n",
-				opc->ssid, 0, 0 );
-			continue;
-		}
+		/* First time thru, check for possible skips */
+		if ( saveit || op->o_tag == LDAP_REQ_ADD ) {
 
-		/* Don't send ops back to the messenger */
-		if ( scook && scook->sid > 0 && scook->sid == ss->s_sid ) {
-			Debug( LDAP_DEBUG_SYNC, "syncprov_matchops: skipping relayed sid %03x\n",
-				scook->sid, 0, 0 );
-			continue;
+			/* Don't send ops back to the originator */
+			if ( opc->osid > 0 && opc->osid == ss->s_sid ) {
+				Debug( LDAP_DEBUG_SYNC, "syncprov_matchops: skipping original sid %03x\n",
+					opc->osid, 0, 0 );
+				continue;
+			}
+
+			/* Don't send ops back to the messenger */
+			if ( opc->rsid > 0 && opc->rsid == ss->s_sid ) {
+				Debug( LDAP_DEBUG_SYNC, "syncprov_matchops: skipping relayed sid %03x\n",
+					opc->rsid, 0, 0 );
+				continue;
+			}
 		}
 
 		/* validate base */
@@ -1242,13 +1261,18 @@ syncprov_matchops( Operation *op, opcook
 			oh = *op->o_hdr;
 			oh.oh_conn = ss->s_op->o_conn;
 			oh.oh_connid = ss->s_op->o_connid;
+			op2.o_bd = op->o_bd->bd_self;
 			op2.o_hdr = &oh;
 			op2.o_extra = op->o_extra;
+			op2.o_callback = NULL;
+			rc = test_filter( &op2, e, ss->s_op->ors_filter );
 		}
 
+		Debug( LDAP_DEBUG_TRACE, "syncprov_matchops: sid %03x fscope %d rc %d\n",
+			ss->s_sid, fc.fscope, rc );
+
 		/* check if current o_req_dn is in scope and matches filter */
-		if ( fc.fscope && test_filter( &op2, e, ss->s_op->ors_filter ) ==
-			LDAP_COMPARE_TRUE ) {
+		if ( fc.fscope && rc == LDAP_COMPARE_TRUE ) {
 			if ( saveit ) {
 				sm = op->o_tmpalloc( sizeof(syncmatches), op->o_tmpmemctx );
 				sm->sm_next = opc->smatches;
@@ -1307,26 +1331,23 @@ syncprov_op_cleanup( Operation *op, Slap
 	}
 
 	/* Remove op from lock table */
-	mtdummy.mt_op = op;
-	ldap_pvt_thread_mutex_lock( &si->si_mods_mutex );
-	mt = avl_find( si->si_mods, &mtdummy, sp_avl_cmp );
+	mt = opc->smt;
 	if ( mt ) {
-		modinst *mi = mt->mt_mods;
-
-		/* If there are more, promote the next one */
 		ldap_pvt_thread_mutex_lock( &mt->mt_mutex );
-		if ( mi->mi_next ) {
-			mt->mt_mods = mi->mi_next;
+		mt->mt_mods = mt->mt_mods->mi_next;
+		/* If there are more, promote the next one */
+		if ( mt->mt_mods ) {
 			mt->mt_op = mt->mt_mods->mi_op;
 			ldap_pvt_thread_mutex_unlock( &mt->mt_mutex );
 		} else {
-			avl_delete( &si->si_mods, mt, sp_avl_cmp );
 			ldap_pvt_thread_mutex_unlock( &mt->mt_mutex );
+			ldap_pvt_thread_mutex_lock( &si->si_mods_mutex );
+			avl_delete( &si->si_mods, mt, sp_avl_cmp );
+			ldap_pvt_thread_mutex_unlock( &si->si_mods_mutex );
 			ldap_pvt_thread_mutex_destroy( &mt->mt_mutex );
 			ch_free( mt );
 		}
 	}
-	ldap_pvt_thread_mutex_unlock( &si->si_mods_mutex );
 	if ( !BER_BVISNULL( &opc->suuid ))
 		op->o_tmpfree( opc->suuid.bv_val, op->o_tmpmemctx );
 	if ( !BER_BVISNULL( &opc->sndn ))
@@ -1348,6 +1369,7 @@ syncprov_checkpoint( Operation *op, Slap
 	SlapReply rsm = { 0 };
 	slap_callback cb = {0};
 	BackendDB be;
+
 #ifdef CHECK_CSN
 	Syntax *syn = slap_schema.si_ad_contextCSN->ad_type->sat_syntax;
 
@@ -1374,12 +1396,26 @@ syncprov_checkpoint( Operation *op, Slap
 		be = *on->on_info->oi_origdb;
 		opm.o_bd = &be;
 	}
-	opm.o_req_dn = opm.o_bd->be_suffix[0];
-	opm.o_req_ndn = opm.o_bd->be_nsuffix[0];
+	opm.o_req_dn = si->si_contextdn;
+	opm.o_req_ndn = si->si_contextdn;
 	opm.o_bd->bd_info = on->on_info->oi_orig;
 	opm.o_managedsait = SLAP_CONTROL_NONCRITICAL;
 	opm.o_no_schema_check = 1;
 	opm.o_bd->be_modify( &opm, &rsm );
+
+	if ( rsm.sr_err == LDAP_NO_SUCH_OBJECT &&
+		SLAP_SYNC_SUBENTRY( opm.o_bd )) {
+		const char	*text;
+		char txtbuf[SLAP_TEXT_BUFLEN];
+		size_t textlen = sizeof txtbuf;
+		Entry *e = slap_create_context_csn_entry( opm.o_bd, NULL );
+		slap_mods2entry( &mod, &e, 0, 1, &text, txtbuf, textlen);
+		opm.ora_e = e;
+		opm.o_bd->be_add( &opm, &rsm );
+		if ( e == opm.ora_e )
+			be_entry_release_w( &opm, opm.ora_e );
+	}
+
 	if ( mod.sml_next != NULL ) {
 		slap_mods_free( mod.sml_next, 1 );
 	}
@@ -1455,7 +1491,7 @@ syncprov_playlog( Operation *op, SlapRep
 	slap_overinst		*on = (slap_overinst *)op->o_bd->bd_info;
 	slog_entry *se;
 	int i, j, ndel, num, nmods, mmods;
-	char cbuf[LDAP_LUTIL_CSNSTR_BUFSIZE];
+	char cbuf[LDAP_PVT_CSNSTR_BUFSIZE];
 	BerVarray uuids;
 	struct berval delcsn[2];
 
@@ -1630,17 +1666,18 @@ syncprov_op_response( Operation *op, Sla
 	if ( rs->sr_err == LDAP_SUCCESS )
 	{
 		struct berval maxcsn;
-		char cbuf[LDAP_LUTIL_CSNSTR_BUFSIZE];
+		char cbuf[LDAP_PVT_CSNSTR_BUFSIZE];
 		int do_check = 0, have_psearches, foundit, csn_changed = 0;
 
+		ldap_pvt_thread_mutex_lock( &si->si_resp_mutex );
+
 		/* Update our context CSN */
 		cbuf[0] = '\0';
 		maxcsn.bv_val = cbuf;
 		maxcsn.bv_len = sizeof(cbuf);
 		ldap_pvt_thread_rdwr_wlock( &si->si_csn_rwlock );
 
-#if 0
-		if ( op->o_dont_replicate &&
+		if ( op->o_dont_replicate && op->o_tag == LDAP_REQ_MODIFY &&
 				op->orm_modlist->sml_op == LDAP_MOD_REPLACE &&
 				op->orm_modlist->sml_desc == slap_schema.si_ad_contextCSN ) {
 			/* Catch contextCSN updates from syncrepl. We have to look at
@@ -1687,9 +1724,8 @@ syncprov_op_response( Operation *op, Sla
 					}
 				}
 			}
-			return SLAP_CB_CONTINUE;
+			goto leave;
 		}
-#endif
 
 		slap_get_commit_csn( op, &maxcsn, &foundit );
 		if ( BER_BVISEMPTY( &maxcsn ) && SLAP_GLUE_SUBORDINATE( op->o_bd )) {
@@ -1730,31 +1766,39 @@ syncprov_op_response( Operation *op, Sla
 					sizeof(int));
 				si->si_sids[i] = sid;
 			}
+#if 0
 		} else if ( !foundit ) {
 			/* internal ops that aren't meant to be replicated */
 			ldap_pvt_thread_rdwr_wunlock( &si->si_csn_rwlock );
 			return SLAP_CB_CONTINUE;
+#endif
 		}
 
 		/* Don't do any processing for consumer contextCSN updates */
 		if ( op->o_dont_replicate ) {
 			ldap_pvt_thread_rdwr_wunlock( &si->si_csn_rwlock );
-			return SLAP_CB_CONTINUE;
+			goto leave;
 		}
 
 		si->si_numops++;
 		if ( si->si_chkops || si->si_chktime ) {
-			if ( si->si_chkops && si->si_numops >= si->si_chkops ) {
-				do_check = 1;
-				si->si_numops = 0;
-			}
-			if ( si->si_chktime &&
-				(op->o_time - si->si_chklast >= si->si_chktime )) {
-				if ( si->si_chklast ) {
+			/* Never checkpoint adding the context entry,
+			 * it will deadlock
+			 */
+			if ( op->o_tag != LDAP_REQ_ADD ||
+				!dn_match( &op->o_req_ndn, &si->si_contextdn )) {
+				if ( si->si_chkops && si->si_numops >= si->si_chkops ) {
 					do_check = 1;
-					si->si_chklast = op->o_time;
-				} else {
-					si->si_chklast = 1;
+					si->si_numops = 0;
+				}
+				if ( si->si_chktime &&
+					(op->o_time - si->si_chklast >= si->si_chktime )) {
+					if ( si->si_chklast ) {
+						do_check = 1;
+						si->si_chklast = op->o_time;
+					} else {
+						si->si_chklast = 1;
+					}
 				}
 			}
 		}
@@ -1800,7 +1844,7 @@ syncprov_op_response( Operation *op, Sla
 		if ( si->si_logs && op->o_tag != LDAP_REQ_ADD ) {
 			syncprov_add_slog( op );
 		}
-
+leave:		ldap_pvt_thread_mutex_unlock( &si->si_resp_mutex );
 	}
 	return SLAP_CB_CONTINUE;
 }
@@ -1816,14 +1860,14 @@ syncprov_op_compare( Operation *op, Slap
 	syncprov_info_t		*si = on->on_bi.bi_private;
 	int rc = SLAP_CB_CONTINUE;
 
-	if ( dn_match( &op->o_req_ndn, op->o_bd->be_nsuffix ) &&
+	if ( dn_match( &op->o_req_ndn, &si->si_contextdn ) &&
 		op->oq_compare.rs_ava->aa_desc == slap_schema.si_ad_contextCSN )
 	{
 		Entry e = {0};
 		Attribute a = {0};
 
-		e.e_name = op->o_bd->be_suffix[0];
-		e.e_nname = op->o_bd->be_nsuffix[0];
+		e.e_name = si->si_contextdn;
+		e.e_nname = si->si_contextdn;
 		e.e_attrs = &a;
 
 		a.a_desc = slap_schema.si_ad_contextCSN;
@@ -1899,10 +1943,16 @@ syncprov_op_mod( Operation *op, SlapRepl
 	cb->sc_next = op->o_callback;
 	op->o_callback = cb;
 
+	opc->osid = -1;
+	opc->rsid = -1;
 	if ( op->o_csn.bv_val ) {
-		opc->ssid = slap_parse_csn_sid( &op->o_csn );
-	} else {
-		opc->ssid = -1;
+		opc->osid = slap_parse_csn_sid( &op->o_csn );
+	}
+	if ( op->o_controls ) {
+		struct sync_cookie *scook =
+		op->o_controls[slap_cids.sc_LDAPsync];
+		if ( scook )
+			opc->rsid = scook->sid;
 	}
 
 	/* If there are active persistent searches, lock this operation.
@@ -1921,6 +1971,15 @@ syncprov_op_mod( Operation *op, SlapRepl
 		mt = avl_find( si->si_mods, &mtdummy, sp_avl_cmp );
 		if ( mt ) {
 			ldap_pvt_thread_mutex_lock( &mt->mt_mutex );
+			if ( mt->mt_mods == NULL ) {
+				/* Cannot reuse this mt, as another thread is about
+				 * to release it in syncprov_op_cleanup.
+				 */
+				ldap_pvt_thread_mutex_unlock( &mt->mt_mutex );
+				mt = NULL;
+			}
+		}
+		if ( mt ) {
 			ldap_pvt_thread_mutex_unlock( &si->si_mods_mutex );
 			mt->mt_tail->mi_next = mi;
 			mt->mt_tail = mi;
@@ -1932,6 +1991,9 @@ syncprov_op_mod( Operation *op, SlapRepl
 				 * Currently it's not an issue because there are
 				 * no dynamic config deletes...
 				 */
+				if ( slapd_shutdown )
+					return SLAPD_ABANDON;
+
 				if ( !ldap_pvt_thread_pool_pausecheck( &connection_pool ))
 					ldap_pvt_thread_yield();
 				ldap_pvt_thread_mutex_lock( &mt->mt_mutex );
@@ -1959,6 +2021,7 @@ syncprov_op_mod( Operation *op, SlapRepl
 			avl_insert( &si->si_mods, mt, sp_avl_cmp, avl_dup_error );
 			ldap_pvt_thread_mutex_unlock( &si->si_mods_mutex );
 		}
+		opc->smt = mt;
 	}
 
 	if (( have_psearches || si->si_logs ) && op->o_tag != LDAP_REQ_ADD )
@@ -2182,9 +2245,10 @@ syncprov_search_response( Operation *op,
 				LDAP_SYNC_ADD, rs->sr_ctrls, 0, 0, NULL );
 		}
 	} else if ( rs->sr_type == REP_RESULT && rs->sr_err == LDAP_SUCCESS ) {
-		struct berval cookie;
+		struct berval cookie = BER_BVNULL;
 
-		if ( ss->ss_flags & SS_CHANGED ) {
+		if ( ( ss->ss_flags & SS_CHANGED ) &&
+			ss->ss_ctxcsn && !BER_BVISNULL( &ss->ss_ctxcsn[0] )) {
 			slap_compose_sync_cookie( op, &cookie, ss->ss_ctxcsn,
 				srs->sr_state.rid, slap_serverID ? slap_serverID : -1 );
 
@@ -2208,7 +2272,7 @@ syncprov_search_response( Operation *op,
 	 			LDAP_TAG_SYNC_REFRESH_PRESENT : LDAP_TAG_SYNC_REFRESH_DELETE,
 				( ss->ss_flags & SS_CHANGED ) ? &cookie : NULL,
 				1, NULL, 0 );
-			if ( ss->ss_flags & SS_CHANGED )
+			if ( !BER_BVISNULL( &cookie ))
 				op->o_tmpfree( cookie.bv_val, op->o_tmpmemctx );
 
 			/* Detach this Op from frontend control */
@@ -2362,13 +2426,32 @@ syncprov_op_search( Operation *op, SlapR
 
 		/* If nothing has changed, shortcut it */
 		if ( srs->sr_state.numcsns == numcsns ) {
-			int i, j;
+			int i, j, newer;
 			for ( i=0; i<srs->sr_state.numcsns; i++ ) {
 				for ( j=0; j<numcsns; j++ ) {
 					if ( srs->sr_state.sids[i] != sids[j] )
 						continue;
-					if ( !bvmatch( &srs->sr_state.ctxcsn[i], &ctxcsn[j] ))
+					newer = ber_bvcmp( &srs->sr_state.ctxcsn[i], &ctxcsn[j] );
+					/* If our state is newer, tell consumer about changes */
+					if ( newer < 0 )
 						changed = SS_CHANGED;
+					else if ( newer > 0 ) {
+					/* our state is older, tell consumer nothing */
+						if ( sop ) {
+							syncops **sp = &si->si_ops;
+							
+							ldap_pvt_thread_mutex_lock( &si->si_ops_mutex );
+							while ( *sp != sop )
+								sp = &(*sp)->s_next;
+							*sp = sop->s_next;
+							ldap_pvt_thread_mutex_unlock( &si->si_ops_mutex );
+							ch_free( sop );
+						}
+						rs->sr_err = LDAP_SUCCESS;
+						rs->sr_ctrls = NULL;
+						send_ldap_result( op, rs );
+						return rs->sr_err;
+					}
 					break;
 				}
 				if ( changed )
@@ -2523,7 +2606,7 @@ syncprov_operational(
 		return SLAP_CB_CONTINUE;
 
 	if ( rs->sr_entry &&
-		dn_match( &rs->sr_entry->e_nname, op->o_bd->be_nsuffix )) {
+		dn_match( &rs->sr_entry->e_nname, &si->si_contextdn )) {
 
 		if ( SLAP_OPATTRS( rs->sr_attr_flags ) ||
 			ad_inlist( slap_schema.si_ad_contextCSN, rs->sr_attrs )) {
@@ -2630,8 +2713,11 @@ sp_cf_gen(ConfigArgs *c)
 		case SP_CHKPT:
 			if ( si->si_chkops || si->si_chktime ) {
 				struct berval bv;
+				/* we assume si_chktime is a multiple of 60
+				 * because the parsed value was originally
+				 * multiplied by 60 */
 				bv.bv_len = snprintf( c->cr_msg, sizeof( c->cr_msg ),
-					"%d %d", si->si_chkops, si->si_chktime );
+					"%d %d", si->si_chkops, si->si_chktime/60 );
 				if ( bv.bv_len >= sizeof( c->cr_msg ) ) {
 					rc = 1;
 				} else {
@@ -2737,7 +2823,7 @@ sp_cf_gen(ConfigArgs *c)
 		}
 		sl = si->si_logs;
 		if ( !sl ) {
-			sl = ch_malloc( sizeof( sessionlog ) + LDAP_LUTIL_CSNSTR_BUFSIZE );
+			sl = ch_malloc( sizeof( sessionlog ) + LDAP_PVT_CSNSTR_BUFSIZE );
 			sl->sl_mincsn.bv_val = (char *)(sl+1);
 			sl->sl_mincsn.bv_len = 0;
 			sl->sl_num = 0;
@@ -2813,7 +2899,13 @@ syncprov_db_open(
 	op->o_dn = be->be_rootdn;
 	op->o_ndn = be->be_rootndn;
 
-	rc = overlay_entry_get_ov( op, be->be_nsuffix, NULL,
+	if ( SLAP_SYNC_SUBENTRY( be )) {
+		build_new_dn( &si->si_contextdn, be->be_nsuffix,
+			(struct berval *)&slap_ldapsync_cn_bv, NULL );
+	} else {
+		si->si_contextdn = be->be_nsuffix[0];
+	}
+	rc = overlay_entry_get_ov( op, &si->si_contextdn, NULL,
 		slap_schema.si_ad_contextCSN, 0, &e, on );
 
 	if ( e ) {
@@ -2837,7 +2929,7 @@ syncprov_db_open(
 
 	/* Didn't find a contextCSN, should we generate one? */
 	if ( !si->si_ctxcsn ) {
-		char csnbuf[ LDAP_LUTIL_CSNSTR_BUFSIZE ];
+		char csnbuf[ LDAP_PVT_CSNSTR_BUFSIZE ];
 		struct berval csn;
 
 		if ( SLAP_SYNC_SHADOW( op->o_bd )) {
@@ -2918,6 +3010,7 @@ syncprov_db_init(
 	ldap_pvt_thread_rdwr_init( &si->si_csn_rwlock );
 	ldap_pvt_thread_mutex_init( &si->si_ops_mutex );
 	ldap_pvt_thread_mutex_init( &si->si_mods_mutex );
+	ldap_pvt_thread_mutex_init( &si->si_resp_mutex );
 
 	csn_anlist[0].an_desc = slap_schema.si_ad_entryCSN;
 	csn_anlist[0].an_name = slap_schema.si_ad_entryCSN->ad_cname;
@@ -2955,6 +3048,7 @@ syncprov_db_destroy(
 			ber_bvarray_free( si->si_ctxcsn );
 		if ( si->si_sids )
 			ch_free( si->si_sids );
+		ldap_pvt_thread_mutex_destroy( &si->si_resp_mutex );
 		ldap_pvt_thread_mutex_destroy( &si->si_mods_mutex );
 		ldap_pvt_thread_mutex_destroy( &si->si_ops_mutex );
 		ldap_pvt_thread_rdwr_destroy( &si->si_csn_rwlock );