Refactor RDMA netlink infrastructure

index 91b7a2fe5a55..d7e29d86469b 100644
@@ -4531,9 +4531,7 @@ static int __init cma_init(void)
 	if (ret)
 		goto err;
 
-	if (ibnl_add_client(RDMA_NL_RDMA_CM, ARRAY_SIZE(cma_cb_table),
-			    cma_cb_table))
-		pr_warn("RDMA CMA: failed to add netlink callback\n");
+	rdma_nl_register(RDMA_NL_RDMA_CM, cma_cb_table);
 	cma_configfs_init();
 
 	return 0;

@@ -4550,7 +4548,7 @@ static int __init cma_init(void)
 static void __exit cma_cleanup(void)
 {
 	cma_configfs_exit();
-	ibnl_remove_client(RDMA_NL_RDMA_CM);
+	rdma_nl_unregister(RDMA_NL_RDMA_CM);
 	ib_unregister_client(&cma_client);
 	unregister_netdevice_notifier(&cma_nb);
 	rdma_addr_unregister_client(&addr_client);

83 lines not on this page · raw message

index 31661b5c1743..8599271d8be6 100644
@@ -1175,12 +1175,8 @@ static int __init iw_cm_init(void)
 	ret = iwpm_init(RDMA_NL_IWCM);
 	if (ret)
 		pr_err("iw_cm: couldn't init iwpm\n");
-
-	ret = ibnl_add_client(RDMA_NL_IWCM, ARRAY_SIZE(iwcm_nl_cb_table),
-			      iwcm_nl_cb_table);
-	if (ret)
-		pr_err("iw_cm: couldn't register netlink callbacks\n");
-
+	else
+		rdma_nl_register(RDMA_NL_IWCM, iwcm_nl_cb_table);
 	iwcm_wq = alloc_ordered_workqueue("iw_cm_wq", WQ_MEM_RECLAIM);
 	if (!iwcm_wq)
 		return -ENOMEM;

@@ -1200,7 +1196,7 @@ static void __exit iw_cm_cleanup(void)
 {
 	unregister_net_sysctl_table(iwcm_ctl_table_hdr);
 	destroy_workqueue(iwcm_wq);
-	ibnl_remove_client(RDMA_NL_IWCM);
+	rdma_nl_unregister(RDMA_NL_IWCM);
 	iwpm_exit(RDMA_NL_IWCM);
 }
 

249 lines not on this page · raw message

index 585266144329..6735dcf5d2a3 100644
@@ -10,27 +10,22 @@ struct ibnl_client_cbs {
 	struct module *module;
 };
 
-int ibnl_init(void);
-void ibnl_cleanup(void);
+int rdma_nl_init(void);
+void rdma_nl_exit(void);
 
 /**
- * Add a a client to the list of IB netlink exporters.
+ * Register client in RDMA netlink.
  * @index: Index of the added client
- * @nops: Number of supported ops by the added client.
  * @cb_table: A table for op->callback
- *
- * Returns 0 on success or a negative error code.
  */
-int ibnl_add_client(int index, int nops,
-		    const struct ibnl_client_cbs cb_table[]);
+void rdma_nl_register(unsigned int index,
+		      const struct ibnl_client_cbs cb_table[]);
 
 /**
  * Remove a client from IB netlink.
  * @index: Index of the removed IB client.
- *
- * Returns 0 on success or a negative error code.
  */
-int ibnl_remove_client(int index);
+void rdma_nl_unregister(unsigned int index);
 
 /**
  * Put a new message in a supplied skb.

index 5852661..348c102 100644
@@ -10,9 +10,6 @@ struct ibnl_client_cbs {
        struct module *module;
 };
 
-int ibnl_init(void);
-void ibnl_cleanup(void);
-
 
 

index d7e29d86469b..a4013b0908e2 100644
@@ -4478,8 +4478,7 @@ static int cma_get_id_stats(struct sk_buff *skb, struct netlink_callback *cb)
 }
 
 static const struct ibnl_client_cbs cma_cb_table[] = {
-	[RDMA_NL_RDMA_CM_ID_STATS] = { .dump = cma_get_id_stats,
-				       .module = THIS_MODULE },
+	[RDMA_NL_RDMA_CM_ID_STATS] = { .dump = cma_get_id_stats},
 };
 
 static int cma_init_net(struct net *net)

index ea5d46c34054..b18fa9c2dce6 100644
@@ -180,12 +180,10 @@ static int ibnl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
 		cb.skb = skb;
 		cb.nlh = nlh;
 		cb.dump = rdma_nl_types[index].cb_table[op].dump;
-		cb.module = rdma_nl_types[index].cb_table[op].module;
 		return cb.dump(skb, &cb);
 	}
 
 	c.dump = rdma_nl_types[index].cb_table[op].dump;
-	c.module = rdma_nl_types[index].cb_table[op].module;
 	return netlink_dump_start(nls, skb, nlh, &c);
 }
 

index 6735dcf5d2a3..761517105a36 100644
@@ -7,7 +7,6 @@
 
 struct ibnl_client_cbs {
 	int (*dump)(struct sk_buff *skb, struct netlink_callback *nlcb);
-	struct module *module;
 };
 
 int rdma_nl_init(void);

index b18fa9c2dce6..4fa6746a62b1 100644
@@ -159,8 +159,8 @@ int ibnl_put_attr(struct sk_buff *skb, struct nlmsghdr *nlh,
 }
 EXPORT_SYMBOL(ibnl_put_attr);
 
-static int ibnl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
-			struct netlink_ext_ack *extack)
+static int rdma_nl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+			   struct netlink_ext_ack *extack)
 {
 	int type = nlh->nlmsg_type;
 	unsigned int index = RDMA_NL_GET_CLIENT(type);

@@ -187,40 +187,66 @@ static int ibnl_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
 	return netlink_dump_start(nls, skb, nlh, &c);
 }
 
-static void ibnl_rcv_reply_skb(struct sk_buff *skb)
+/*
+ * This function is similar to netlink_rcv_skb with one exception:
+ * It calls to the callback for the netlink messages without NLM_F_REQUEST
+ * flag. These messages are intended for RDMA_NL_LS consumer, so it is allowed
+ * for that consumer only.
+ */
+static int rdma_nl_rcv_skb(struct sk_buff *skb, int (*cb)(struct sk_buff *,
+						   struct nlmsghdr *,
+						   struct netlink_ext_ack *))
 {
+	struct netlink_ext_ack extack = {};
 	struct nlmsghdr *nlh;
-	int msglen;
+	int err;
 
-	/*
-	 * Process responses until there is no more message or the first
-	 * request. Generally speaking, it is not recommended to mix responses
-	 * with requests.
-	 */
 	while (skb->len >= nlmsg_total_size(0)) {
+		int msglen;
+
 		nlh = nlmsg_hdr(skb);
+		err = 0;
 
 		if (nlh->nlmsg_len < NLMSG_HDRLEN || skb->len < nlh->nlmsg_len)
-			return;
+			return 0;
 
-		/* Handle response only */
-		if (nlh->nlmsg_flags & NLM_F_REQUEST)
-			return;
+		/*
+		 * Generally speaking, the only requests are handled
+		 * by the kernel, but RDMA_NL_LS is different, because it
+		 * runs backward netlink scheme. Kernel initiates messages
+		 * and waits for reply with data to keep pathrecord cache
+		 * in sync.
+		 */
+		if (!(nlh->nlmsg_flags & NLM_F_REQUEST) &&
+		    (RDMA_NL_GET_CLIENT(nlh->nlmsg_type) != RDMA_NL_LS))
+			goto ack;
+
+		/* Skip control messages */
+		if (nlh->nlmsg_type < NLMSG_MIN_TYPE)
+			goto ack;
+
+		err = cb(skb, nlh, &extack);
+		if (err == -EINTR)
+			goto skip;
 
-		ibnl_rcv_msg(skb, nlh, NULL);
+ack:
+		if (nlh->nlmsg_flags & NLM_F_ACK || err)
+			netlink_ack(skb, nlh, err, &extack);
 
+skip:
 		msglen = NLMSG_ALIGN(nlh->nlmsg_len);
 		if (msglen > skb->len)
 			msglen = skb->len;
 		skb_pull(skb, msglen);
 	}
+
+	return 0;
 }
 
-static void ibnl_rcv(struct sk_buff *skb)
+static void rdma_nl_rcv(struct sk_buff *skb)
 {
 	mutex_lock(&rdma_nl_mutex);
-	ibnl_rcv_reply_skb(skb);
-	netlink_rcv_skb(skb, &ibnl_rcv_msg);
+	rdma_nl_rcv_skb(skb, &rdma_nl_rcv_msg);
 	mutex_unlock(&rdma_nl_mutex);
 }
 

@@ -241,7 +267,7 @@ EXPORT_SYMBOL(ibnl_multicast);
 int __init rdma_nl_init(void)
 {
 	struct netlink_kernel_cfg cfg = {
-		.input	= ibnl_rcv,
+		.input	= rdma_nl_rcv,
 	};
 
 	nls = netlink_kernel_create(&init_net, NETLINK_RDMA, &cfg);

index f13870e69ccd..32ca2aaa4e3b 100644
@@ -54,8 +54,6 @@ static struct iwpm_admin_data iwpm_admin;
 int iwpm_init(u8 nl_client)
 {
 	int ret = 0;
-	if (iwpm_valid_client(nl_client))
-		return -EINVAL;
 	mutex_lock(&iwpm_admin_lock);
 	if (atomic_read(&iwpm_admin.refcount) == 0) {
 		iwpm_hash_bucket = kzalloc(IWPM_MAPINFO_HASH_SIZE *

@@ -383,15 +381,11 @@ int iwpm_get_nlmsg_seq(void)
 
 int iwpm_valid_client(u8 nl_client)
 {
-	if (nl_client >= RDMA_NL_NUM_CLIENTS)
-		return 0;
 	return iwpm_admin.client_list[nl_client];
 }
 
 void iwpm_set_valid(u8 nl_client, int valid)
 {
-	if (nl_client >= RDMA_NL_NUM_CLIENTS)
-		return;
 	iwpm_admin.client_list[nl_client] = valid;
 }
 

index a0e7c16d8bd8..1fab707b1f68 100644
@@ -42,7 +42,6 @@ int iwpm_valid_pid(void)
 {
 	return iwpm_user_pid > 0;
 }
-EXPORT_SYMBOL(iwpm_valid_pid);
 
 /*
  * iwpm_register_pid - Send a netlink query to user space

@@ -122,7 +121,6 @@ int iwpm_register_pid(struct iwpm_dev_data *pm_msg, u8 nl_client)
 		iwpm_free_nlmsg_request(&nlmsg_request->kref);
 	return ret;
 }
-EXPORT_SYMBOL(iwpm_register_pid);
 
 /*
  * iwpm_add_mapping - Send a netlink add mapping message

@@ -191,7 +189,6 @@ int iwpm_add_mapping(struct iwpm_sa_data *pm_msg, u8 nl_client)
 		iwpm_free_nlmsg_request(&nlmsg_request->kref);
 	return ret;
 }
-EXPORT_SYMBOL(iwpm_add_mapping);
 
 /*
  * iwpm_add_and_query_mapping - Send a netlink add and query

@@ -267,7 +264,6 @@ int iwpm_add_and_query_mapping(struct iwpm_sa_data *pm_msg, u8 nl_client)
 		iwpm_free_nlmsg_request(&nlmsg_request->kref);
 	return ret;
 }
-EXPORT_SYMBOL(iwpm_add_and_query_mapping);
 
 /*
  * iwpm_remove_mapping - Send a netlink remove mapping message

@@ -328,7 +324,6 @@ int iwpm_remove_mapping(struct sockaddr_storage *local_addr, u8 nl_client)
 		dev_kfree_skb_any(skb);
 	return ret;
 }
-EXPORT_SYMBOL(iwpm_remove_mapping);
 
 /* netlink attribute policy for the received response to register pid request */
 static const struct nla_policy resp_reg_policy[IWPM_NLA_RREG_PID_MAX] = {

@@ -397,7 +392,6 @@ int iwpm_register_pid_cb(struct sk_buff *skb, struct netlink_callback *cb)
 	up(&nlmsg_request->sem);
 	return 0;
 }
-EXPORT_SYMBOL(iwpm_register_pid_cb);
 
 /* netlink attribute policy for the received response to add mapping request */
 static const struct nla_policy resp_add_policy[IWPM_NLA_RMANAGE_MAPPING_MAX] = {

@@ -466,7 +460,6 @@ int iwpm_add_mapping_cb(struct sk_buff *skb, struct netlink_callback *cb)
 	up(&nlmsg_request->sem);
 	return 0;
 }
-EXPORT_SYMBOL(iwpm_add_mapping_cb);
 
 /* netlink attribute policy for the response to add and query mapping request
  * and response with remote address info */

@@ -558,7 +551,6 @@ int iwpm_add_and_query_mapping_cb(struct sk_buff *skb,
 	up(&nlmsg_request->sem);
 	return 0;
 }
-EXPORT_SYMBOL(iwpm_add_and_query_mapping_cb);
 
 /*
  * iwpm_remote_info_cb - Process a port mapper message, containing

@@ -627,7 +619,6 @@ int iwpm_remote_info_cb(struct sk_buff *skb, struct netlink_callback *cb)
 			"remote_info: Mapped remote sockaddr:");
 	return ret;
 }
-EXPORT_SYMBOL(iwpm_remote_info_cb);
 
 /* netlink attribute policy for the received request for mapping info */
 static const struct nla_policy resp_mapinfo_policy[IWPM_NLA_MAPINFO_REQ_MAX] = {

@@ -677,7 +668,6 @@ int iwpm_mapping_info_cb(struct sk_buff *skb, struct netlink_callback *cb)
 	ret = iwpm_send_mapinfo(nl_client, iwpm_user_pid);
 	return ret;
 }
-EXPORT_SYMBOL(iwpm_mapping_info_cb);
 
 /* netlink attribute policy for the received mapping info ack */
 static const struct nla_policy ack_mapinfo_policy[IWPM_NLA_MAPINFO_NUM_MAX] = {

@@ -707,7 +697,6 @@ int iwpm_ack_mapping_info_cb(struct sk_buff *skb, struct netlink_callback *cb)
 	atomic_set(&echo_nlmsg_seq, cb->nlh->nlmsg_seq);
 	return 0;
 }
-EXPORT_SYMBOL(iwpm_ack_mapping_info_cb);
 
 /* netlink attribute policy for the received port mapper error message */
 static const struct nla_policy map_error_policy[IWPM_NLA_ERR_MAX] = {

@@ -751,4 +740,3 @@ int iwpm_mapping_error_cb(struct sk_buff *skb, struct netlink_callback *cb)
 	up(&nlmsg_request->sem);
 	return 0;
 }
-EXPORT_SYMBOL(iwpm_mapping_error_cb);

index 32ca2aaa4e3b..c46442ac71a2 100644
@@ -81,7 +81,6 @@ int iwpm_init(u8 nl_client)
 	}
 	return ret;
 }
-EXPORT_SYMBOL(iwpm_init);
 
 static void free_hash_bucket(void);
 static void free_reminfo_bucket(void);

@@ -107,7 +106,6 @@ int iwpm_exit(u8 nl_client)
 	iwpm_set_registration(nl_client, IWPM_REG_UNDEF);
 	return 0;
 }
-EXPORT_SYMBOL(iwpm_exit);
 
 static struct hlist_head *get_mapinfo_hash_bucket(struct sockaddr_storage *,
 					       struct sockaddr_storage *);

@@ -146,7 +144,6 @@ int iwpm_create_mapinfo(struct sockaddr_storage *local_sockaddr,
 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
 	return ret;
 }
-EXPORT_SYMBOL(iwpm_create_mapinfo);
 
 int iwpm_remove_mapinfo(struct sockaddr_storage *local_sockaddr,
 			struct sockaddr_storage *mapped_local_addr)

@@ -182,7 +179,6 @@ int iwpm_remove_mapinfo(struct sockaddr_storage *local_sockaddr,
 	spin_unlock_irqrestore(&iwpm_mapinfo_lock, flags);
 	return ret;
 }
-EXPORT_SYMBOL(iwpm_remove_mapinfo);
 
 static void free_hash_bucket(void)
 {

@@ -295,7 +291,6 @@ int iwpm_get_remote_info(struct sockaddr_storage *mapped_loc_addr,
 	spin_unlock_irqrestore(&iwpm_reminfo_lock, flags);
 	return ret;
 }
-EXPORT_SYMBOL(iwpm_get_remote_info);
 
 struct iwpm_nlmsg_request *iwpm_get_nlmsg_request(__u32 nlmsg_seq,
 					u8 nl_client, gfp_t gfp)