net/smc: move link group list to smc_core

This patch moves the global link group list to smc_core where the link
group functions are. To make this work, it moves code in af_smc and
smc_ib that operates on the link group list to smc_core as well.

While at it, the link group counter is integrated into the list
structure and initialized to zero.

Signed-off-by: Hans Wippel <hwippel@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/smc/af_smc.c

@@ -46,11 +46,6 @@ static DEFINE_MUTEX(smc_create_lgr_pending);	/* serialize link group
 						 * creation
 						 */
 
-struct smc_lgr_list smc_lgr_list = {		/* established link groups */
-	.lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock),
-	.list = LIST_HEAD_INIT(smc_lgr_list.list),
-};
-
 static void smc_tcp_listen_work(struct work_struct *);
 
 static void smc_set_keepalive(struct sock *sk, int val)
@@ -1637,19 +1632,7 @@ static int __init smc_init(void)
 
 static void __exit smc_exit(void)
 {
-	struct smc_link_group *lgr, *lg;
-	LIST_HEAD(lgr_freeing_list);
-
-	spin_lock_bh(&smc_lgr_list.lock);
-	if (!list_empty(&smc_lgr_list.list))
-		list_splice_init(&smc_lgr_list.list, &lgr_freeing_list);
-	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 */
-	}
+	smc_core_exit();
 	static_branch_disable(&tcp_have_smc);
 	smc_ib_unregister_client();
 	sock_unregister(PF_SMC);

net/smc/smc_core.c

@@ -30,7 +30,11 @@
 #define SMC_LGR_FREE_DELAY_SERV		(600 * HZ)
 #define SMC_LGR_FREE_DELAY_CLNT		(SMC_LGR_FREE_DELAY_SERV + 10)
 
-static u32 smc_lgr_num;			/* unique link group number */
+static struct smc_lgr_list smc_lgr_list = {	/* established link groups */
+	.lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock),
+	.list = LIST_HEAD_INIT(smc_lgr_list.list),
+	.num = 0,
+};
 
 static void smc_buf_free(struct smc_buf_desc *buf_desc, struct smc_link *lnk,
 			 bool is_rmb);
@@ -181,8 +185,8 @@ static int smc_lgr_create(struct smc_sock *smc,
 		INIT_LIST_HEAD(&lgr->sndbufs[i]);
 		INIT_LIST_HEAD(&lgr->rmbs[i]);
 	}
-	smc_lgr_num += SMC_LGR_NUM_INCR;
-	memcpy(&lgr->id, (u8 *)&smc_lgr_num, SMC_LGR_ID_SIZE);
+	smc_lgr_list.num += SMC_LGR_NUM_INCR;
+	memcpy(&lgr->id, (u8 *)&smc_lgr_list.num, SMC_LGR_ID_SIZE);
 	INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work);
 	lgr->conns_all = RB_ROOT;
 
@@ -374,6 +378,18 @@ void smc_lgr_terminate(struct smc_link_group *lgr)
 	smc_lgr_schedule_free_work(lgr);
 }
 
+/* Called when IB port is terminated */
+void smc_port_terminate(struct smc_ib_device *smcibdev, u8 ibport)
+{
+	struct smc_link_group *lgr, *l;
+
+	list_for_each_entry_safe(lgr, l, &smc_lgr_list.list, list) {
+		if (lgr->lnk[SMC_SINGLE_LINK].smcibdev == smcibdev &&
+		    lgr->lnk[SMC_SINGLE_LINK].ibport == ibport)
+			smc_lgr_terminate(lgr);
+	}
+}
+
 /* Determine vlan of internal TCP socket.
  * @vlan_id: address to store the determined vlan id into
  */
@@ -802,3 +818,21 @@ int smc_rmb_rtoken_handling(struct smc_connection *conn,
 		return conn->rtoken_idx;
 	return 0;
 }
+
+/* Called (from smc_exit) when module is removed */
+void smc_core_exit(void)
+{
+	struct smc_link_group *lgr, *lg;
+	LIST_HEAD(lgr_freeing_list);
+
+	spin_lock_bh(&smc_lgr_list.lock);
+	if (!list_empty(&smc_lgr_list.list))
+		list_splice_init(&smc_lgr_list.list, &lgr_freeing_list);
+	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_core.h

@@ -23,10 +23,9 @@
 struct smc_lgr_list {			/* list of link group definition */
 	struct list_head	list;
 	spinlock_t		lock;	/* protects list of link groups */
+	u32			num;	/* unique link group number */
 };
 
-extern struct smc_lgr_list	smc_lgr_list; /* list of link groups */
-
 enum smc_lgr_role {		/* possible roles of a link group */
 	SMC_CLNT,	/* client */
 	SMC_SERV	/* server */
@@ -210,6 +209,7 @@ struct smc_clc_msg_accept_confirm;
 void smc_lgr_free(struct smc_link_group *lgr);
 void smc_lgr_forget(struct smc_link_group *lgr);
 void smc_lgr_terminate(struct smc_link_group *lgr);
+void smc_port_terminate(struct smc_ib_device *smcibdev, u8 ibport);
 int smc_buf_create(struct smc_sock *smc);
 int smc_rmb_rtoken_handling(struct smc_connection *conn,
 			    struct smc_clc_msg_accept_confirm *clc);
@@ -219,4 +219,5 @@ void smc_sndbuf_sync_sg_for_cpu(struct smc_connection *conn);
 void smc_sndbuf_sync_sg_for_device(struct smc_connection *conn);
 void smc_rmb_sync_sg_for_cpu(struct smc_connection *conn);
 void smc_rmb_sync_sg_for_device(struct smc_connection *conn);
+void smc_core_exit(void);
 #endif

net/smc/smc_ib.c

@@ -143,17 +143,6 @@ int smc_ib_ready_link(struct smc_link *lnk)
 	return rc;
 }
 
-static void smc_ib_port_terminate(struct smc_ib_device *smcibdev, u8 ibport)
-{
-	struct smc_link_group *lgr, *l;
-
-	list_for_each_entry_safe(lgr, l, &smc_lgr_list.list, list) {
-		if (lgr->lnk[SMC_SINGLE_LINK].smcibdev == smcibdev &&
-		    lgr->lnk[SMC_SINGLE_LINK].ibport == ibport)
-			smc_lgr_terminate(lgr);
-	}
-}
-
 /* process context wrapper for might_sleep smc_ib_remember_port_attr */
 static void smc_ib_port_event_work(struct work_struct *work)
 {
@@ -165,7 +154,7 @@ static void smc_ib_port_event_work(struct work_struct *work)
 		smc_ib_remember_port_attr(smcibdev, port_idx + 1);
 		clear_bit(port_idx, &smcibdev->port_event_mask);
 		if (!smc_ib_port_active(smcibdev, port_idx + 1))
-			smc_ib_port_terminate(smcibdev, port_idx + 1);
+			smc_port_terminate(smcibdev, port_idx + 1);
 	}
 }