net/smc: add pnetid support for SMC-D and ISM

SMC-D relies on PNETIDs to find usable SMC-D/ISM devices for a SMC
connection. This patch adds SMC-D/ISM support to the current PNETID
implementation.
Signed-off-by: Hans Wippel <hwippel@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Suggested-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/smc.h

@@ -73,6 +73,7 @@ struct smcd_dev {
 	struct smc_connection **conn;
 	struct list_head vlan;
 	struct workqueue_struct *event_wq;
+	u8 pnetid[SMC_MAX_PNETID_LEN];
 };
 
 struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name,

net/smc/smc_ism.c

@@ -13,6 +13,7 @@
 #include "smc.h"
 #include "smc_core.h"
 #include "smc_ism.h"
+#include "smc_pnet.h"
 
 struct smcd_dev_list smcd_dev_list = {
 	.list = LIST_HEAD_INIT(smcd_dev_list.list),
@@ -227,6 +228,7 @@ struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name,
 	device_initialize(&smcd->dev);
 	dev_set_name(&smcd->dev, name);
 	smcd->ops = ops;
+	smc_pnetid_by_dev_port(parent, 0, smcd->pnetid);
 
 	spin_lock_init(&smcd->lock);
 	INIT_LIST_HEAD(&smcd->vlan);

net/smc/smc_pnet.c

@@ -22,6 +22,7 @@
 
 #include "smc_pnet.h"
 #include "smc_ib.h"
+#include "smc_ism.h"
 
 static struct nla_policy smc_pnet_policy[SMC_PNETID_MAX + 1] = {
 	[SMC_PNETID_NAME] = {
@@ -564,6 +565,27 @@ static void smc_pnet_find_roce_by_pnetid(struct net_device *ndev,
 	spin_unlock(&smc_ib_devices.lock);
 }
 
+static void smc_pnet_find_ism_by_pnetid(struct net_device *ndev,
+					struct smcd_dev **smcismdev)
+{
+	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
+	struct smcd_dev *ismdev;
+
+	ndev = pnet_find_base_ndev(ndev);
+	if (smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
+				   ndev_pnetid))
+		return; /* pnetid could not be determined */
+
+	spin_lock(&smcd_dev_list.lock);
+	list_for_each_entry(ismdev, &smcd_dev_list.list, list) {
+		if (!memcmp(ismdev->pnetid, ndev_pnetid, SMC_MAX_PNETID_LEN)) {
+			*smcismdev = ismdev;
+			break;
+		}
+	}
+	spin_unlock(&smcd_dev_list.lock);
+}
+
 /* Lookup of coupled ib_device via SMC pnet table */
 static void smc_pnet_find_roce_by_table(struct net_device *netdev,
 					struct smc_ib_device **smcibdev,
@@ -615,3 +637,22 @@ void smc_pnet_find_roce_resource(struct sock *sk,
 out:
 	return;
 }
+
+void smc_pnet_find_ism_resource(struct sock *sk, struct smcd_dev **smcismdev)
+{
+	struct dst_entry *dst = sk_dst_get(sk);
+
+	*smcismdev = NULL;
+	if (!dst)
+		goto out;
+	if (!dst->dev)
+		goto out_rel;
+
+	/* if possible, lookup via hardware-defined pnetid */
+	smc_pnet_find_ism_by_pnetid(dst->dev, smcismdev);
+
+out_rel:
+	dst_release(dst);
+out:
+	return;
+}

net/smc/smc_pnet.h

@@ -17,6 +17,7 @@
 #endif
 
 struct smc_ib_device;
+struct smcd_dev;
 
 static inline int smc_pnetid_by_dev_port(struct device *dev,
 					 unsigned short port, u8 *pnetid)
@@ -33,5 +34,6 @@ void smc_pnet_exit(void);
 int smc_pnet_remove_by_ibdev(struct smc_ib_device *ibdev);
 void smc_pnet_find_roce_resource(struct sock *sk,
 				 struct smc_ib_device **smcibdev, u8 *ibport);
+void smc_pnet_find_ism_resource(struct sock *sk, struct smcd_dev **smcismdev);
 
 #endif