Merge branch 'net-smc-enhancements-2018-05-15'

Ursula Braun says:

====================
net/smc: enhancements 2018/05/15

here are smc patches for net-next. The first one is a fix for net-next
commit 01d2f7e2 "net/smc: sockopts TCP_NODELAY and TCP_CORK".
Patch 7 improves Connection Layer Control error handling, patch 10
improves abnormal termination of link groups. The remaining patches
from Karsten improve Link Layer Control code.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

net/smc/af_smc.c

@@ -293,14 +293,22 @@ static void smc_copy_sock_settings_to_smc(struct smc_sock *smc)
 	smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC);
 }
 
-/* register a new rmb */
-static int smc_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc)
+/* register a new rmb, optionally send confirm_rkey msg to register with peer */
+static int smc_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc,
+		       bool conf_rkey)
 {
 	/* register memory region for new rmb */
 	if (smc_wr_reg_send(link, rmb_desc->mr_rx[SMC_SINGLE_LINK])) {
 		rmb_desc->regerr = 1;
 		return -EFAULT;
 	}
+	if (!conf_rkey)
+		return 0;
+	/* exchange confirm_rkey msg with peer */
+	if (smc_llc_do_confirm_rkey(link, rmb_desc)) {
+		rmb_desc->regerr = 1;
+		return -EFAULT;
+	}
 	return 0;
 }
 
@@ -334,7 +342,7 @@ static int smc_clnt_conf_first_link(struct smc_sock *smc)
 
 	smc_wr_remember_qp_attr(link);
 
-	if (smc_reg_rmb(link, smc->conn.rmb_desc))
+	if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
 		return SMC_CLC_DECL_INTERR;
 
 	/* send CONFIRM LINK response over RoCE fabric */
@@ -455,6 +463,8 @@ static int smc_connect_rdma(struct smc_sock *smc)
 			reason_code = SMC_CLC_DECL_MEM;/* insufficient memory*/
 		else if (rc == -ENOLINK)
 			reason_code = SMC_CLC_DECL_SYNCERR; /* synchr. error */
+		else
+			reason_code = SMC_CLC_DECL_INTERR; /* other error */
 		goto decline_rdma_unlock;
 	}
 	link = &smc->conn.lgr->lnk[SMC_SINGLE_LINK];
@@ -488,7 +498,7 @@ static int smc_connect_rdma(struct smc_sock *smc)
 		}
 	} else {
 		if (!smc->conn.rmb_desc->reused) {
-			if (smc_reg_rmb(link, smc->conn.rmb_desc)) {
+			if (smc_reg_rmb(link, smc->conn.rmb_desc, true)) {
 				reason_code = SMC_CLC_DECL_INTERR;
 				goto decline_rdma_unlock;
 			}
@@ -729,7 +739,7 @@ static int smc_serv_conf_first_link(struct smc_sock *smc)
 
 	link = &lgr->lnk[SMC_SINGLE_LINK];
 
-	if (smc_reg_rmb(link, smc->conn.rmb_desc))
+	if (smc_reg_rmb(link, smc->conn.rmb_desc, false))
 		return SMC_CLC_DECL_INTERR;
 
 	/* send CONFIRM LINK request to client over the RoCE fabric */
@@ -866,7 +876,7 @@ static void smc_listen_work(struct work_struct *work)
 
 	if (local_contact != SMC_FIRST_CONTACT) {
 		if (!new_smc->conn.rmb_desc->reused) {
-			if (smc_reg_rmb(link, new_smc->conn.rmb_desc)) {
+			if (smc_reg_rmb(link, new_smc->conn.rmb_desc, true)) {
 				reason_code = SMC_CLC_DECL_INTERR;
 				goto decline_rdma_unlock;
 			}
@@ -1353,14 +1363,14 @@ static int smc_setsockopt(struct socket *sock, int level, int optname,
 		break;
 	case TCP_NODELAY:
 		if (sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) {
-			if (val)
+			if (val && !smc->use_fallback)
 				mod_delayed_work(system_wq, &smc->conn.tx_work,
 						 0);
 		}
 		break;
 	case TCP_CORK:
 		if (sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) {
-			if (!val)
+			if (!val && !smc->use_fallback)
 				mod_delayed_work(system_wq, &smc->conn.tx_work,
 						 0);
 		}
@@ -1634,6 +1644,7 @@ static void __exit smc_exit(void)
 	spin_unlock_bh(&smc_lgr_list.lock);
 	list_for_each_entry_safe(lgr, lg, &lgr_freeing_list, list) {
 		list_del_init(&lgr->list);
+		smc_llc_link_inactive(&lgr->lnk[SMC_SINGLE_LINK]);
 		cancel_delayed_work_sync(&lgr->free_work);
 		smc_lgr_free(lgr); /* free link group */
 	}

net/smc/smc_clc.c

@@ -316,7 +316,7 @@ int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
 	if (clcm->type == SMC_CLC_DECLINE) {
 		reason_code = SMC_CLC_DECL_REPLY;
 		if (((struct smc_clc_msg_decline *)buf)->hdr.flag) {
-			smc->conn.lgr->sync_err = true;
+			smc->conn.lgr->sync_err = 1;
 			smc_lgr_terminate(smc->conn.lgr);
 		}
 	}

net/smc/smc_core.c

@@ -148,8 +148,11 @@ static void smc_lgr_free_work(struct work_struct *work)
 	list_del_init(&lgr->list); /* remove from smc_lgr_list */
 free:
 	spin_unlock_bh(&smc_lgr_list.lock);
-	if (!delayed_work_pending(&lgr->free_work))
+	if (!delayed_work_pending(&lgr->free_work)) {
+		if (lgr->lnk[SMC_SINGLE_LINK].state != SMC_LNK_INACTIVE)
+			smc_llc_link_inactive(&lgr->lnk[SMC_SINGLE_LINK]);
 		smc_lgr_free(lgr);
+	}
 }
 
 /* create a new SMC link group */
@@ -169,7 +172,7 @@ static int smc_lgr_create(struct smc_sock *smc,
 		goto out;
 	}
 	lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT;
-	lgr->sync_err = false;
+	lgr->sync_err = 0;
 	memcpy(lgr->peer_systemid, peer_systemid, SMC_SYSTEMID_LEN);
 	lgr->vlan_id = vlan_id;
 	rwlock_init(&lgr->sndbufs_lock);
@@ -194,9 +197,12 @@ static int smc_lgr_create(struct smc_sock *smc,
 		smc_ib_setup_per_ibdev(smcibdev);
 	get_random_bytes(rndvec, sizeof(rndvec));
 	lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) + (rndvec[2] << 16);
-	rc = smc_wr_alloc_link_mem(lnk);
+	rc = smc_llc_link_init(lnk);
 	if (rc)
 		goto free_lgr;
+	rc = smc_wr_alloc_link_mem(lnk);
+	if (rc)
+		goto clear_llc_lnk;
 	rc = smc_ib_create_protection_domain(lnk);
 	if (rc)
 		goto free_link_mem;
@@ -206,10 +212,6 @@ static int smc_lgr_create(struct smc_sock *smc,
 	rc = smc_wr_create_link(lnk);
 	if (rc)
 		goto destroy_qp;
-	init_completion(&lnk->llc_confirm);
-	init_completion(&lnk->llc_confirm_resp);
-	init_completion(&lnk->llc_add);
-	init_completion(&lnk->llc_add_resp);
 
 	smc->conn.lgr = lgr;
 	rwlock_init(&lgr->conns_lock);
@@ -224,6 +226,8 @@ static int smc_lgr_create(struct smc_sock *smc,
 	smc_ib_dealloc_protection_domain(lnk);
 free_link_mem:
 	smc_wr_free_link_mem(lnk);
+clear_llc_lnk:
+	smc_llc_link_clear(lnk);
 free_lgr:
 	kfree(lgr);
 out:
@@ -269,6 +273,7 @@ void smc_conn_free(struct smc_connection *conn)
 static void smc_link_clear(struct smc_link *lnk)
 {
 	lnk->peer_qpn = 0;
+	smc_llc_link_clear(lnk);
 	smc_ib_modify_qp_reset(lnk);
 	smc_wr_free_link(lnk);
 	smc_ib_destroy_queue_pair(lnk);
@@ -326,7 +331,6 @@ static void smc_lgr_free_bufs(struct smc_link_group *lgr)
 /* remove a link group */
 void smc_lgr_free(struct smc_link_group *lgr)
 {
-	smc_llc_link_flush(&lgr->lnk[SMC_SINGLE_LINK]);
 	smc_lgr_free_bufs(lgr);
 	smc_link_clear(&lgr->lnk[SMC_SINGLE_LINK]);
 	kfree(lgr);
@@ -348,6 +352,9 @@ void smc_lgr_terminate(struct smc_link_group *lgr)
 	struct smc_sock *smc;
 	struct rb_node *node;
 
+	if (lgr->terminating)
+		return;	/* lgr already terminating */
+	lgr->terminating = 1;
 	smc_lgr_forget(lgr);
 	smc_llc_link_inactive(&lgr->lnk[SMC_SINGLE_LINK]);
 

net/smc/smc_core.h

@@ -96,6 +96,7 @@ struct smc_link {
 	u8			link_id;	/* unique # within link group */
 
 	enum smc_link_state	state;		/* state of link */
+	struct workqueue_struct *llc_wq;	/* single thread work queue */
 	struct completion	llc_confirm;	/* wait for rx of conf link */
 	struct completion	llc_confirm_resp; /* wait 4 rx of cnf lnk rsp */
 	int			llc_confirm_rc; /* rc from confirm link msg */
@@ -105,6 +106,8 @@ struct smc_link {
 	struct delayed_work	llc_testlink_wrk; /* testlink worker */
 	struct completion	llc_testlink_resp; /* wait for rx of testlink */
 	int			llc_testlink_time; /* testlink interval */
+	struct completion	llc_confirm_rkey; /* wait 4 rx of cnf rkey */
+	int			llc_confirm_rkey_rc; /* rc from cnf rkey msg */
 };
 
 /* For now we just allow one parallel link per link group. The SMC protocol
@@ -163,7 +166,8 @@ struct smc_link_group {
 
 	u8			id[SMC_LGR_ID_SIZE];	/* unique lgr id */
 	struct delayed_work	free_work;	/* delayed freeing of an lgr */
-	bool			sync_err;	/* lgr no longer fits to peer */
+	u8			sync_err : 1;	/* lgr no longer fits to peer */
+	u8			terminating : 1;/* lgr is terminating */
 };
 
 /* Find the connection associated with the given alert token in the link group.

net/smc/smc_llc.h

@@ -42,11 +42,12 @@ int smc_llc_send_add_link(struct smc_link *link, u8 mac[], union ib_gid *gid,
 			  enum smc_llc_reqresp reqresp);
 int smc_llc_send_delete_link(struct smc_link *link,
 			     enum smc_llc_reqresp reqresp);
-int smc_llc_send_test_link(struct smc_link *lnk, u8 user_data[16],
-			   enum smc_llc_reqresp reqresp);
+int smc_llc_link_init(struct smc_link *link);
 void smc_llc_link_active(struct smc_link *link, int testlink_time);
 void smc_llc_link_inactive(struct smc_link *link);
-void smc_llc_link_flush(struct smc_link *link);
+void smc_llc_link_clear(struct smc_link *link);
+int smc_llc_do_confirm_rkey(struct smc_link *link,
+			    struct smc_buf_desc *rmb_desc);
 int smc_llc_init(void) __init;
 
 #endif /* SMC_LLC_H */