RDMA/rxe: Use ib_device_get_by_netdev() instead of open coding

The core API handles the locking correctly and is faster if there are
multiple devices.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/sw/rxe/rxe.h

@@ -105,9 +105,19 @@ static inline void rxe_dev_put(struct rxe_dev *rxe)
 {
 	kref_put(&rxe->ref_cnt, rxe_release);
 }
-struct rxe_dev *net_to_rxe(struct net_device *ndev);
 struct rxe_dev *get_rxe_by_name(const char *name);
 
+/* The caller must do a matching ib_device_put(&dev->ib_dev) */
+static inline struct rxe_dev *rxe_get_dev_from_net(struct net_device *ndev)
+{
+	struct ib_device *ibdev =
+		ib_device_get_by_netdev(ndev, RDMA_DRIVER_RXE);
+
+	if (!ibdev)
+		return NULL;
+	return container_of(ibdev, struct rxe_dev, ib_dev);
+}
+
 void rxe_port_up(struct rxe_dev *rxe);
 void rxe_port_down(struct rxe_dev *rxe);
 void rxe_set_port_state(struct rxe_dev *rxe);

drivers/infiniband/sw/rxe/rxe_net.c

@@ -48,23 +48,6 @@
 static LIST_HEAD(rxe_dev_list);
 static DEFINE_SPINLOCK(dev_list_lock); /* spinlock for device list */
 
-struct rxe_dev *net_to_rxe(struct net_device *ndev)
-{
-	struct rxe_dev *rxe;
-	struct rxe_dev *found = NULL;
-
-	spin_lock_bh(&dev_list_lock);
-	list_for_each_entry(rxe, &rxe_dev_list, list) {
-		if (rxe->ndev == ndev) {
-			found = rxe;
-			break;
-		}
-	}
-	spin_unlock_bh(&dev_list_lock);
-
-	return found;
-}
-
 struct rxe_dev *get_rxe_by_name(const char *name)
 {
 	struct rxe_dev *rxe;
@@ -81,7 +64,6 @@ struct rxe_dev *get_rxe_by_name(const char *name)
 	return found;
 }
 
-
 static struct rxe_recv_sockets recv_sockets;
 
 struct device *rxe_dma_device(struct rxe_dev *rxe)
@@ -229,18 +211,19 @@ static int rxe_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
 	struct udphdr *udph;
 	struct net_device *ndev = skb->dev;
 	struct net_device *rdev = ndev;
-	struct rxe_dev *rxe = net_to_rxe(ndev);
+	struct rxe_dev *rxe = rxe_get_dev_from_net(ndev);
 	struct rxe_pkt_info *pkt = SKB_TO_PKT(skb);
 
 	if (!rxe && is_vlan_dev(rdev)) {
 		rdev = vlan_dev_real_dev(ndev);
-		rxe = net_to_rxe(rdev);
+		rxe = rxe_get_dev_from_net(rdev);
 	}
 	if (!rxe)
 		goto drop;
 
 	if (skb_linearize(skb)) {
 		pr_err("skb_linearize failed\n");
+		ib_device_put(&rxe->ib_dev);
 		goto drop;
 	}
 
@@ -253,6 +236,12 @@ static int rxe_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
 
 	rxe_rcv(skb);
 
+	/*
+	 * FIXME: this is in the wrong place, it needs to be done when pkt is
+	 * destroyed
+	 */
+	ib_device_put(&rxe->ib_dev);
+
 	return 0;
 drop:
 	kfree_skb(skb);
@@ -635,16 +624,17 @@ static int rxe_notify(struct notifier_block *not_blk,
 		      void *arg)
 {
 	struct net_device *ndev = netdev_notifier_info_to_dev(arg);
-	struct rxe_dev *rxe = net_to_rxe(ndev);
+	struct rxe_dev *rxe = rxe_get_dev_from_net(ndev);
 
 	if (!rxe)
-		goto out;
+		return NOTIFY_OK;
 
 	switch (event) {
 	case NETDEV_UNREGISTER:
 		list_del(&rxe->list);
+		ib_device_put(&rxe->ib_dev);
 		rxe_remove(rxe);
-		break;
+		return NOTIFY_OK;
 	case NETDEV_UP:
 		rxe_port_up(rxe);
 		break;
@@ -668,7 +658,8 @@ static int rxe_notify(struct notifier_block *not_blk,
 			event, ndev->name);
 		break;
 	}
-out:
+
+	ib_device_put(&rxe->ib_dev);
 	return NOTIFY_OK;
 }
 

drivers/infiniband/sw/rxe/rxe_sysfs.c

@@ -58,24 +58,25 @@ static int rxe_param_set_add(const char *val, const struct kernel_param *kp)
 	int len;
 	int err = 0;
 	char intf[32];
-	struct net_device *ndev = NULL;
+	struct net_device *ndev;
+	struct rxe_dev *exists;
 	struct rxe_dev *rxe;
 
 	len = sanitize_arg(val, intf, sizeof(intf));
 	if (!len) {
 		pr_err("add: invalid interface name\n");
-		err = -EINVAL;
+		return -EINVAL;
-		goto err;
 	}
 
 	ndev = dev_get_by_name(&init_net, intf);
 	if (!ndev) {
 		pr_err("interface %s not found\n", intf);
-		err = -EINVAL;
+		return -EINVAL;
-		goto err;
 	}
 
-	if (net_to_rxe(ndev)) {
+	exists = rxe_get_dev_from_net(ndev);
+	if (exists) {
+		ib_device_put(&exists->ib_dev);
 		pr_err("already configured on %s\n", intf);
 		err = -EINVAL;
 		goto err;
@@ -90,9 +91,9 @@ static int rxe_param_set_add(const char *val, const struct kernel_param *kp)
 
 	rxe_set_port_state(rxe);
 	dev_info(&rxe->ib_dev.dev, "added %s\n", intf);
+
 err:
-	if (ndev)
+	dev_put(ndev);
-		dev_put(ndev);
 	return err;
 }
 

drivers/infiniband/sw/rxe/rxe_verbs.c

@@ -80,19 +80,6 @@ static int rxe_query_port(struct ib_device *dev,
 	return rc;
 }
 
-static struct net_device *rxe_get_netdev(struct ib_device *device,
-					 u8 port_num)
-{
-	struct rxe_dev *rxe = to_rdev(device);
-
-	if (rxe->ndev) {
-		dev_hold(rxe->ndev);
-		return rxe->ndev;
-	}
-
-	return NULL;
-}
-
 static int rxe_query_pkey(struct ib_device *device,
 			  u8 port_num, u16 index, u16 *pkey)
 {
@@ -1159,7 +1146,6 @@ static const struct ib_device_ops rxe_dev_ops = {
 	.get_dma_mr = rxe_get_dma_mr,
 	.get_hw_stats = rxe_ib_get_hw_stats,
 	.get_link_layer = rxe_get_link_layer,
-	.get_netdev = rxe_get_netdev,
 	.get_port_immutable = rxe_port_immutable,
 	.map_mr_sg = rxe_map_mr_sg,
 	.mmap = rxe_mmap,
@@ -1240,6 +1226,9 @@ int rxe_register_device(struct rxe_dev *rxe)
 	    ;
 
 	ib_set_device_ops(dev, &rxe_dev_ops);
+	err = ib_device_set_netdev(&rxe->ib_dev, rxe->ndev, 1);
+	if (err)
+		return err;
 
 	tfm = crypto_alloc_shash("crc32", 0, 0);
 	if (IS_ERR(tfm)) {