rdma_rxe: Use netlink messages to add/delete links

Add support for the RDMA_NLDEV_CMD_NEWLINK/DELLINK messages which allow
dynamically adding new RXE links.  Deprecate the old module options for
now.

Cc: Moni Shoua <monis@mellanox.com>
Reviewed-by: Yanjun Zhu <yanjun.zhu@oracle.com>
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/sw/rxe/rxe.c

@@ -31,6 +31,7 @@
  * SOFTWARE.
  */
 
+#include <rdma/rdma_netlink.h>
 #include <net/addrconf.h>
 #include "rxe.h"
 #include "rxe_loc.h"
@@ -301,7 +302,7 @@ void rxe_set_mtu(struct rxe_dev *rxe, unsigned int ndev_mtu)
 /* called by ifc layer to create new rxe device.
  * The caller should allocate memory for rxe by calling ib_alloc_device.
  */
-int rxe_add(struct rxe_dev *rxe, unsigned int mtu)
+int rxe_add(struct rxe_dev *rxe, unsigned int mtu, const char *ibdev_name)
 {
 	int err;
 
@@ -311,9 +312,36 @@ int rxe_add(struct rxe_dev *rxe, unsigned int mtu)
 
 	rxe_set_mtu(rxe, mtu);
 
-	return rxe_register_device(rxe);
+	return rxe_register_device(rxe, ibdev_name);
 }
 
+static int rxe_newlink(const char *ibdev_name, struct net_device *ndev)
+{
+	struct rxe_dev *exists;
+	int err = 0;
+
+	exists = rxe_get_dev_from_net(ndev);
+	if (exists) {
+		ib_device_put(&exists->ib_dev);
+		pr_err("already configured on %s\n", ndev->name);
+		err = -EEXIST;
+		goto err;
+	}
+
+	err = rxe_net_add(ibdev_name, ndev);
+	if (err) {
+		pr_err("failed to add %s\n", ndev->name);
+		goto err;
+	}
+err:
+	return err;
+}
+
+static struct rdma_link_ops rxe_link_ops = {
+	.type = "rxe",
+	.newlink = rxe_newlink,
+};
+
 static int __init rxe_module_init(void)
 {
 	int err;
@@ -329,12 +357,14 @@ static int __init rxe_module_init(void)
 	if (err)
 		return err;
 
+	rdma_link_register(&rxe_link_ops);
 	pr_info("loaded\n");
 	return 0;
 }
 
 static void __exit rxe_module_exit(void)
 {
+	rdma_link_unregister(&rxe_link_ops);
 	ib_unregister_driver(RDMA_DRIVER_RXE);
 	rxe_net_exit();
 	rxe_cache_exit();
@@ -344,3 +374,5 @@ static void __exit rxe_module_exit(void)
 
 late_initcall(rxe_module_init);
 module_exit(rxe_module_exit);
+
+MODULE_ALIAS_RDMA_LINK("rxe");

drivers/infiniband/sw/rxe/rxe.h

@@ -95,7 +95,7 @@ static inline u32 rxe_crc32(struct rxe_dev *rxe,
 
 void rxe_set_mtu(struct rxe_dev *rxe, unsigned int dev_mtu);
 
-int rxe_add(struct rxe_dev *rxe, unsigned int mtu);
+int rxe_add(struct rxe_dev *rxe, unsigned int mtu, const char *ibdev_name);
 
 void rxe_rcv(struct sk_buff *skb);
 

drivers/infiniband/sw/rxe/rxe_net.c

@@ -517,7 +517,7 @@ enum rdma_link_layer rxe_link_layer(struct rxe_dev *rxe, unsigned int port_num)
 	return IB_LINK_LAYER_ETHERNET;
 }
 
-int rxe_net_add(struct net_device *ndev)
+int rxe_net_add(const char *ibdev_name, struct net_device *ndev)
 {
 	int err;
 	struct rxe_dev *rxe = NULL;
@@ -528,7 +528,7 @@ int rxe_net_add(struct net_device *ndev)
 
 	rxe->ndev = ndev;
 
-	err = rxe_add(rxe, ndev->mtu);
+	err = rxe_add(rxe, ndev->mtu, ibdev_name);
 	if (err) {
 		ib_dealloc_device(&rxe->ib_dev);
 		return err;

drivers/infiniband/sw/rxe/rxe_net.h

@@ -43,7 +43,7 @@ struct rxe_recv_sockets {
 	struct socket *sk6;
 };
 
-int rxe_net_add(struct net_device *ndev);
+int rxe_net_add(const char *ibdev_name, struct net_device *ndev);
 
 int rxe_net_init(void);
 void rxe_net_exit(void);

drivers/infiniband/sw/rxe/rxe_param.h

@@ -78,7 +78,8 @@ enum rxe_device_param {
 					| IB_DEVICE_SYS_IMAGE_GUID
 					| IB_DEVICE_RC_RNR_NAK_GEN
 					| IB_DEVICE_SRQ_RESIZE
-					| IB_DEVICE_MEM_MGT_EXTENSIONS,
+					| IB_DEVICE_MEM_MGT_EXTENSIONS
+					| IB_DEVICE_ALLOW_USER_UNREG,
 	RXE_MAX_SGE			= 32,
 	RXE_MAX_SGE_RD			= 32,
 	RXE_MAX_CQ			= 16384,

drivers/infiniband/sw/rxe/rxe_sysfs.c

@@ -81,7 +81,7 @@ static int rxe_param_set_add(const char *val, const struct kernel_param *kp)
 		goto err;
 	}
 
-	err = rxe_net_add(ndev);
+	err = rxe_net_add("rxe%d", ndev);
 	if (err) {
 		pr_err("failed to add %s\n", intf);
 		goto err;
@@ -130,6 +130,6 @@ static const struct kernel_param_ops rxe_remove_ops = {
 };
 
 module_param_cb(add, &rxe_add_ops, NULL, 0200);
-MODULE_PARM_DESC(add, "Create RXE device over network interface");
+MODULE_PARM_DESC(add, "DEPRECATED.  Create RXE device over network interface");
 module_param_cb(remove, &rxe_remove_ops, NULL, 0200);
-MODULE_PARM_DESC(remove, "Remove RXE device over network interface");
+MODULE_PARM_DESC(remove, "DEPRECATED.  Remove RXE device over network interface");

drivers/infiniband/sw/rxe/rxe_verbs.c

@@ -1182,7 +1182,7 @@ static const struct ib_device_ops rxe_dev_ops = {
 	INIT_RDMA_OBJ_SIZE(ib_pd, rxe_pd, ibpd),
 };
 
-int rxe_register_device(struct rxe_dev *rxe)
+int rxe_register_device(struct rxe_dev *rxe, const char *ibdev_name)
 {
 	int err;
 	struct ib_device *dev = &rxe->ib_dev;
@@ -1251,7 +1251,7 @@ int rxe_register_device(struct rxe_dev *rxe)
 
 	rdma_set_device_sysfs_group(dev, &rxe_attr_group);
 	dev->driver_id = RDMA_DRIVER_RXE;
-	err = ib_register_device(dev, "rxe%d");
+	err = ib_register_device(dev, ibdev_name);
 	if (err)
 		pr_warn("%s failed with error %d\n", __func__, err);
 

drivers/infiniband/sw/rxe/rxe_verbs.h

@@ -464,7 +464,7 @@ static inline struct rxe_mem *to_rmw(struct ib_mw *mw)
 	return mw ? container_of(mw, struct rxe_mem, ibmw) : NULL;
 }
 
-int rxe_register_device(struct rxe_dev *rxe);
+int rxe_register_device(struct rxe_dev *rxe, const char *ibdev_name);
 
 void rxe_mc_cleanup(struct rxe_pool_entry *arg);