[wan hdlc] new private struct pointer in hdlc_device, and helpers for it

New field in hdlc_device: void *priv;
New helpers:
        struct net_device *alloc_hdlcdev(priv) allocates hdlc, sets ->priv and
returns pointer to hdlc->netdev
        free_hdlcdev(dev) takes such pointer and frees its hdlc.

wanxl switched to use of those; instead of embedding hdlc into card->ports[]
we allocate it separately right after card had been allocated and store pointer
to hdlc->netdev in card->ports[]->dev.  Freeing is done just before freeing
card.  Pointer back to card->ports[] is stored in hdlc->priv.  port_to_dev()
and dev_to_port() rewritten in the obvious way; by now the rest of driver
doesn't care whether hdlc is embedded or not - everything uses port_to_dev()
and dev_to_port().

That killed embedded hdlc replacing it with pointer to net_device.  Fairly
similar work will be done in the next few patches for other drivers.

Additionally, setup-after-register and free_irq()-before-unregister races
had been fixed.

drivers/net/wan/hdlc_generic.c

@@ -226,7 +226,15 @@ int hdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 	}
 }
 
-
+struct net_device *alloc_hdlcdev(void *priv)
+{
+	void *p = kmalloc(sizeof(hdlc_device), GFP_KERNEL);
+	if (p) {
+		memset(p, 0, sizeof(hdlc_device));
+		dev_to_hdlc(p)->priv = priv;
+	}
+	return p;
+}
 
 int register_hdlc_device(struct net_device *dev)
 {
@@ -279,6 +287,7 @@ EXPORT_SYMBOL(hdlc_open);
 EXPORT_SYMBOL(hdlc_close);
 EXPORT_SYMBOL(hdlc_set_carrier);
 EXPORT_SYMBOL(hdlc_ioctl);
+EXPORT_SYMBOL(alloc_hdlcdev);
 EXPORT_SYMBOL(register_hdlc_device);
 EXPORT_SYMBOL(unregister_hdlc_device);
 

drivers/net/wan/wanxl.c

@@ -51,7 +51,7 @@ static const char* version = "wanXL serial card driver version: 0.47";
 
 
 typedef struct {
-	hdlc_device hdlc;	/* HDLC device struct - must be first */
+	struct net_device *dev;
 	struct card_t *card;
 	spinlock_t lock;	/* for wanxl_xmit */
         int node;		/* physical port #0 - 3 */
@@ -78,19 +78,20 @@ typedef struct card_t {
 	struct sk_buff *rx_skbs[RX_QUEUE_LENGTH];
 	card_status_t *status;	/* shared between host and card */
 	dma_addr_t status_address;
+	port_t __ports[0];
 }card_t;
 
 
 
 static inline port_t* dev_to_port(struct net_device *dev)
 {
-        return (port_t *)(dev_to_hdlc(dev));
+        return (port_t *)dev_to_hdlc(dev)->priv;
 }
 
 
 static inline struct net_device *port_to_dev(port_t* port)
 {
-        return hdlc_to_dev(&port->hdlc);
+        return port->dev;
 }
 
 
@@ -527,16 +528,16 @@ static void wanxl_pci_remove_one(struct pci_dev *pdev)
 	card_t *card = pci_get_drvdata(pdev);
 	int i;
 
-	/* unregister and free all host resources */
-	if (card->irq)
-		free_irq(card->irq, card);
-
 	for (i = 0; i < 4; i++)
 		if (card->ports[i]) {
 			struct net_device *dev = port_to_dev(card->ports[i]);
 			unregister_hdlc_device(dev);
 		}
 
+	/* unregister and free all host resources */
+	if (card->irq)
+		free_irq(card->irq, card);
+
 	wanxl_reset(card);
 
 	for (i = 0; i < RX_QUEUE_LENGTH; i++)
@@ -554,6 +555,10 @@ static void wanxl_pci_remove_one(struct pci_dev *pdev)
 		pci_free_consistent(pdev, sizeof(card_status_t),
 				    card->status, card->status_address);
 
+	for (i = 0; i < card->n_ports; i++)
+		if (card->__ports[i].dev)
+			free_hdlcdev(card->__ports[i].dev);
+
 	pci_set_drvdata(pdev, NULL);
 	kfree(card);
 	pci_release_regions(pdev);
@@ -622,6 +627,16 @@ static int __devinit wanxl_pci_init_one(struct pci_dev *pdev,
 	card->pdev = pdev;
 	card->n_ports = ports;
 
+	for (i = 0; i < ports; i++) {
+		card->__ports[i].dev = alloc_hdlcdev(&card->__ports[i]);
+		if (!card->__ports[i].dev) {
+			printk(KERN_ERR "wanXL %s: unable to allocate memory\n",
+			       card_name(pdev));
+			wanxl_pci_remove_one(pdev);
+			return -ENOMEM;
+		}
+	}
+
 	card->status = pci_alloc_consistent(pdev, sizeof(card_status_t),
 					    &card->status_address);
 	if (card->status == NULL) {
@@ -702,32 +717,6 @@ static int __devinit wanxl_pci_init_one(struct pci_dev *pdev,
 		return -ENODEV;
 	}
 
-	for (i = 0; i < ports; i++) {
-		port_t *port = (void *)card + sizeof(card_t) +
-			i * sizeof(port_t);
-		struct net_device *dev = port_to_dev(port);
-		hdlc_device *hdlc = dev_to_hdlc(dev);
-		spin_lock_init(&port->lock);
-		SET_MODULE_OWNER(dev);
-		dev->tx_queue_len = 50;
-		dev->do_ioctl = wanxl_ioctl;
-		dev->open = wanxl_open;
-		dev->stop = wanxl_close;
-		hdlc->attach = wanxl_attach;
-		hdlc->xmit = wanxl_xmit;
-		if (register_hdlc_device(dev)) {
-			printk(KERN_ERR "wanXL %s: unable to register hdlc"
-			       " device\n", card_name(pdev));
-			wanxl_pci_remove_one(pdev);
-			return -ENOBUFS;
-		}
-		card->ports[i] = port;
-		dev->get_stats = wanxl_get_stats;
-		port->card = card;
-		port->node = i;
-		get_status(port)->clocking = CLOCK_EXT;
-	}
-
 	for (i = 0; i < RX_QUEUE_LENGTH; i++) {
 		struct sk_buff *skb = dev_alloc_skb(BUFFER_LENGTH);
 		card->rx_skbs[i] = skb;
@@ -796,6 +785,32 @@ static int __devinit wanxl_pci_init_one(struct pci_dev *pdev,
 	}
 	card->irq = pdev->irq;
 
+	for (i = 0; i < ports; i++) {
+		port_t *port = &card->__ports[i];
+		struct net_device *dev = port_to_dev(port);
+		hdlc_device *hdlc = dev_to_hdlc(dev);
+		spin_lock_init(&port->lock);
+		SET_MODULE_OWNER(dev);
+		dev->tx_queue_len = 50;
+		dev->do_ioctl = wanxl_ioctl;
+		dev->open = wanxl_open;
+		dev->stop = wanxl_close;
+		hdlc->attach = wanxl_attach;
+		hdlc->xmit = wanxl_xmit;
+		card->ports[i] = port;
+		dev->get_stats = wanxl_get_stats;
+		port->card = card;
+		port->node = i;
+		get_status(port)->clocking = CLOCK_EXT;
+		if (register_hdlc_device(dev)) {
+			printk(KERN_ERR "wanXL %s: unable to register hdlc"
+			       " device\n", card_name(pdev));
+			card->ports[i] = NULL;
+			wanxl_pci_remove_one(pdev);
+			return -ENOBUFS;
+		}
+	}
+
 	return 0;
 }
 

include/linux/hdlc.h

@@ -167,6 +167,7 @@ typedef struct hdlc_device_struct {
 					      int new_mtu);
 		}ppp;
 	}state;
+	void *priv;
 }hdlc_device;
 
 
@@ -188,6 +189,12 @@ int hdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
 int register_hdlc_device(struct net_device *dev);
 void unregister_hdlc_device(struct net_device *dev);
 
+struct net_device *alloc_hdlcdev(void *priv);
+
+static inline void free_hdlcdev(struct net_device *dev)
+{
+	kfree(dev);
+}
 
 static __inline__ struct net_device* hdlc_to_dev(hdlc_device *hdlc)
 {