connector: add portid to unicast in addition to broadcasting

This allows replying only to the requestor portid while still
supporting broadcasting. Pass 0 to portid for the previous behavior.

Signed-off-by: David Fries <[e-mail]>
Acked-by: Evgeniy Polyakov <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

Documentation/connector/cn_test.c

···
 
 		memcpy(m + 1, data, m->len);
 
-		cn_netlink_send(m, 0, GFP_ATOMIC);
+		cn_netlink_send(m, 0, 0, GFP_ATOMIC);
 		kfree(m);
 	}
 

drivers/connector/cn_proc.c

···
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
 	/*  If cn_netlink_send() failed, the data is not sent */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 void proc_exec_connector(struct task_struct *task)
···
 	msg->ack = 0; /* not used */
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 void proc_id_connector(struct task_struct *task, int which_id)
···
 	msg->ack = 0; /* not used */
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 void proc_sid_connector(struct task_struct *task)
···
 	msg->ack = 0; /* not used */
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 void proc_ptrace_connector(struct task_struct *task, int ptrace_id)
···
 	msg->ack = 0; /* not used */
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 void proc_comm_connector(struct task_struct *task)
···
 	msg->ack = 0; /* not used */
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 void proc_coredump_connector(struct task_struct *task)
···
 	msg->ack = 0; /* not used */
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 void proc_exit_connector(struct task_struct *task)
···
 	msg->ack = 0; /* not used */
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 /*
···
 	msg->ack = rcvd_ack + 1;
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 /**

drivers/connector/connector.c

···
  *
  * Sequence number is incremented with each message to be sent.
  *
- * If we expect reply to our message then the sequence number in
+ * If we expect a reply to our message then the sequence number in
  * received message MUST be the same as in original message, and
  * acknowledge number MUST be the same + 1.
  *
···
  * the acknowledgement number in the original message + 1, then it is
  * a new message.
  *
+ * The message is sent to, the portid if given, the group if given, both if
+ * both, or if both are zero then the group is looked up and sent there.
  */
-int cn_netlink_send(struct cn_msg *msg, u32 __group, gfp_t gfp_mask)
+int cn_netlink_send(struct cn_msg *msg, u32 portid, u32 __group,
+	gfp_t gfp_mask)
 {
 	struct cn_callback_entry *__cbq;
 	unsigned int size;
···
 	u32 group = 0;
 	int found = 0;
 
-	if (!__group) {
+	if (portid || __group) {
+		group = __group;
+	} else {
 		spin_lock_bh(&dev->cbdev->queue_lock);
 		list_for_each_entry(__cbq, &dev->cbdev->queue_list,
 				    callback_entry) {
···
 
 		if (!found)
 			return -ENODEV;
-	} else {
-		group = __group;
 	}
 
-	if (!netlink_has_listeners(dev->nls, group))
+	if (!portid && !netlink_has_listeners(dev->nls, group))
 		return -ESRCH;
 
 	size = sizeof(*msg) + msg->len;
···
 
 	NETLINK_CB(skb).dst_group = group;
 
-	return netlink_broadcast(dev->nls, skb, 0, group, gfp_mask);
+	if (group)
+		return netlink_broadcast(dev->nls, skb, portid, group,
+					 gfp_mask);
+	return netlink_unicast(dev->nls, skb, portid, !(gfp_mask&__GFP_WAIT));
 }
 EXPORT_SYMBOL_GPL(cn_netlink_send);
 

drivers/hv/hv_kvp.c

···
 		kvp_msg->kvp_hdr.operation = reg_value;
 		strcpy(version, HV_DRV_VERSION);
 		msg->len = sizeof(struct hv_kvp_msg);
-		cn_netlink_send(msg, 0, GFP_ATOMIC);
+		cn_netlink_send(msg, 0, 0, GFP_ATOMIC);
 		kfree(msg);
 	}
 }
···
 	}
 
 	msg->len = sizeof(struct hv_kvp_msg);
-	cn_netlink_send(msg, 0, GFP_ATOMIC);
+	cn_netlink_send(msg, 0, 0, GFP_ATOMIC);
 	kfree(msg);
 
 	return;

drivers/hv/hv_snapshot.c

···
 	vss_msg->vss_hdr.operation = op;
 	msg->len = sizeof(struct hv_vss_msg);
 
-	cn_netlink_send(msg, 0, GFP_ATOMIC);
+	cn_netlink_send(msg, 0, 0, GFP_ATOMIC);
 	kfree(msg);
 
 	return;

drivers/md/dm-log-userspace-transfer.c

···
 	msg->seq = tfr->seq;
 	msg->len = sizeof(struct dm_ulog_request) + tfr->data_size;
 
-	r = cn_netlink_send(msg, 0, gfp_any());
+	r = cn_netlink_send(msg, 0, 0, gfp_any());
 
 	return r;
 }

drivers/video/uvesafb.c

···
 	uvfb_tasks[seq] = task;
 	mutex_unlock(&uvfb_lock);
 
-	err = cn_netlink_send(m, 0, GFP_KERNEL);
+	err = cn_netlink_send(m, 0, 0, GFP_KERNEL);
 	if (err == -ESRCH) {
 		/*
 		 * Try to start the userspace helper if sending
···
 					"helper is installed and executable\n");
 		} else {
 			v86d_started = 1;
-			err = cn_netlink_send(m, 0, gfp_any());
+			err = cn_netlink_send(m, 0, 0, gfp_any());
 			if (err == -ENOBUFS)
 				err = 0;
 		}

drivers/w1/w1_netlink.c

···
 
 	memcpy(w, msg, sizeof(struct w1_netlink_msg));
 
-	cn_netlink_send(m, 0, GFP_KERNEL);
+	cn_netlink_send(m, 0, 0, GFP_KERNEL);
 }
 
 static void w1_send_slave(struct w1_master *dev, u64 rn)
···
 
 	if (avail < 8) {
 		msg->ack++;
-		cn_netlink_send(msg, 0, GFP_KERNEL);
+		cn_netlink_send(msg, 0, 0, GFP_KERNEL);
 
 		msg->len = sizeof(struct w1_netlink_msg) +
 			sizeof(struct w1_netlink_cmd);
···
 	}
 
 	msg->ack = 0;
-	cn_netlink_send(msg, 0, GFP_KERNEL);
+	cn_netlink_send(msg, 0, 0, GFP_KERNEL);
 
 	dev->priv = NULL;
 	dev->priv_size = 0;
···
 
 	memcpy(c->data, cmd->data, c->len);
 
-	err = cn_netlink_send(cm, 0, GFP_KERNEL);
+	err = cn_netlink_send(cm, 0, 0, GFP_KERNEL);
 
 	kfree(data);
 
···
 	mutex_lock(&w1_mlock);
 	list_for_each_entry(m, &w1_masters, w1_master_entry) {
 		if (cn->len + sizeof(*id) > PAGE_SIZE - sizeof(struct cn_msg)) {
-			cn_netlink_send(cn, 0, GFP_KERNEL);
+			cn_netlink_send(cn, 0, 0, GFP_KERNEL);
 			cn->ack++;
 			cn->len = sizeof(struct w1_netlink_msg);
 			w->len = 0;
···
 		id++;
 	}
 	cn->ack = 0;
-	cn_netlink_send(cn, 0, GFP_KERNEL);
+	cn_netlink_send(cn, 0, 0, GFP_KERNEL);
 	mutex_unlock(&w1_mlock);
 
 	kfree(cn);
···
 		cmsg->len += sizeof(*cmd);
 	}
 
-	error = cn_netlink_send(cmsg, 0, GFP_KERNEL);
+	error = cn_netlink_send(cmsg, 0, 0, GFP_KERNEL);
 	kfree(cmsg);
 
 	return error;

include/linux/connector.h

···
 int cn_add_callback(struct cb_id *id, const char *name,
 		    void (*callback)(struct cn_msg *, struct netlink_skb_parms *));
 void cn_del_callback(struct cb_id *);
-int cn_netlink_send(struct cn_msg *, u32, gfp_t);
+int cn_netlink_send(struct cn_msg *msg, u32 portid, u32 group, gfp_t gfp_mask);
 
 int cn_queue_add_callback(struct cn_queue_dev *dev, const char *name,
 			  struct cb_id *id,