[openib-general] Proposed device enumeration & async event APIs

[Roland Dreier]

    Grant> We don't know which client instances are bound to a
    Grant> particular device?

Nope... think of class_devices and class_interfaces in the current
driver model.

    Grant> But I don't want to turn the IB world upside down to make
    Grant> that work.  If if doesn't make sense, do it the way you
    Grant> proposed originally.

It's easy... like this:

Index: infiniband/core/ib_device.c
===================================================================
--- infiniband/core/ib_device.c	(revision 803)
+++ infiniband/core/ib_device.c	(working copy)
@@ -161,6 +161,28 @@
 }
 EXPORT_SYMBOL(ib_dealloc_device);
 
+static int add_client_context(struct ib_device *device, struct ib_client *client)
+{
+	struct ib_client_data *context;
+	unsigned long flags;
+
+	context = kmalloc(sizeof *context, GFP_KERNEL);
+	if (!context) {
+		printk(KERN_WARNING "Couldn't allocate client context for %s/%s\n",
+		       device->name, client->name);
+		return -ENOMEM;
+	}
+
+	context->client = client;
+	context->data   = NULL;
+
+	spin_lock_irqsave(&device->client_data_lock, flags);
+	list_add(&context->list, &device->client_data_list);
+	spin_unlock_irqrestore(&device->client_data_lock, flags);
+
+	return 0;
+}
+
 int ib_register_device(struct ib_device *device)
 {
 	struct ib_device_private   *priv;
@@ -234,17 +256,10 @@
 		goto out_free_port;
 	}
 
-	ret = ib_proc_setup(device, device->node_type == IB_NODE_SWITCH);
-	if (ret) {
-		printk(KERN_WARNING "Couldn't create /proc dir for %s\n",
-			       device->name);
-		goto out_free_cache;
-	}
-
 	if (ib_device_register_sysfs(device)) {
 		printk(KERN_WARNING "Couldn't register device %s with driver model\n",
 		       device->name);
-		goto out_proc;
+		goto out_free_cache;
 	}
 
 	list_add_tail(&device->core_list, &device_list);
@@ -255,16 +270,13 @@
 		struct ib_client *client;
 
 		list_for_each_entry(client, &client_list, list)
-			if (client->add)
+			if (client->add && !add_client_context(device, client))
 				client->add(device);
 	}
 
 	up(&device_sem);
 	return 0;
 
- out_proc:
-	ib_proc_cleanup(device);
-
  out_free_cache:
 	ib_cache_cleanup(device);
 
@@ -302,7 +314,6 @@
 		kfree(context);
 	spin_unlock_irqrestore(&device->client_data_lock, flags);
 
-	ib_proc_cleanup(device);
 	ib_cache_cleanup(device);
 
 	kfree(priv->port_data);
@@ -355,7 +366,7 @@
 
 	list_add_tail(&client->list, &client_list);
 	list_for_each_entry(device, &device_list, core_list)
-		if (client->add)
+		if (client->add && !add_client_context(device, client))
 			client->add(device);
 
 	up(&device_sem);
@@ -408,34 +419,23 @@
 }
 EXPORT_SYMBOL(ib_get_client_data);
 
-int ib_set_client_data(struct ib_device *device, struct ib_client *client,
-		       void *data)
+void ib_set_client_data(struct ib_device *device, struct ib_client *client,
+			void *data)
 {
 	struct ib_client_data *context;
-	int ret = 0;
 	unsigned long flags;
 
 	spin_lock_irqsave(&device->client_data_lock, flags);
 	list_for_each_entry(context, &device->client_data_list, list)
 		if (context->client == client) {
 			context->data = data;
-			spin_unlock_irqrestore(&device->client_data_lock, flags);
-			return 0;
+			break;
 		}
 
 	spin_unlock_irqrestore(&device->client_data_lock, flags);
-	context = kmalloc(sizeof *context, GFP_KERNEL);
-	if (!context)
-		return -ENOMEM;
 
-	context->client = client;
-	context->data   = data;
-
-	spin_lock_irqsave(&device->client_data_lock, flags);
-	list_add(&context->list, &device->client_data_list);
-	spin_unlock_irqrestore(&device->client_data_lock, flags);
-
-	return 0;
+	printk(KERN_WARNING "No client context found for %s/%s\n",
+	       device->name, client->name);
 }
 EXPORT_SYMBOL(ib_set_client_data);