ISDN: Cleanup/fix isdn.o initialization

A small step in cleaning up isdn.o, fixing various bugs on the error paths.

drivers/isdn/i4l/isdn_common.c

@@ -2247,13 +2247,15 @@ static void isdn_cleanup_devfs(void)
 static int __init isdn_init(void)
 {
 	int i;
+	int retval;
 	char tmprev[50];
 
-	if (!(dev = (isdn_dev *) vmalloc(sizeof(isdn_dev)))) {
-		printk(KERN_WARNING "isdn: Could not allocate device-struct.\n");
-		return -EIO;
+	dev = vmalloc(sizeof(*dev));
+	if (!dev) {
+		retval = -ENOMEM;
+		goto err;
 	}
-	memset((char *) dev, 0, sizeof(isdn_dev));
+	memset(dev, 0, sizeof(*dev));
 	init_timer(&dev->timer);
 	dev->timer.function = isdn_timer_funct;
 	init_MUTEX(&dev->sem);
@@ -2266,34 +2268,22 @@ static int __init isdn_init(void)
 		init_waitqueue_head(&dev->mdm.info[i].open_wait);
 		init_waitqueue_head(&dev->mdm.info[i].close_wait);
 	}
-	if (devfs_register_chrdev(ISDN_MAJOR, "isdn", &isdn_fops)) {
+	retval = devfs_register_chrdev(ISDN_MAJOR, "isdn", &isdn_fops);
+	if (retval) {
 		printk(KERN_WARNING "isdn: Could not register control devices\n");
-		vfree(dev);
-		return -EIO;
+		goto err_vfree;
 	}
 	isdn_init_devfs();
-	if ((i = isdn_tty_modem_init()) < 0) {
+	retval = isdn_tty_init();
+	if (retval < 0) {
 		printk(KERN_WARNING "isdn: Could not register tty devices\n");
-		if (i == -3)
-			tty_unregister_driver(&dev->mdm.cua_modem);
-		if (i <= -2)
-			tty_unregister_driver(&dev->mdm.tty_modem);
-		vfree(dev);
-		isdn_cleanup_devfs();
-		devfs_unregister_chrdev(ISDN_MAJOR, "isdn");
-		return -EIO;
+		goto err_cleanup_devfs;
 	}
 #ifdef CONFIG_ISDN_PPP
-	if (isdn_ppp_init() < 0) {
+	retval = isdn_ppp_init();
+	if (retval < 0) {
 		printk(KERN_WARNING "isdn: Could not create PPP-device-structs\n");
-		tty_unregister_driver(&dev->mdm.tty_modem);
-		tty_unregister_driver(&dev->mdm.cua_modem);
-		for (i = 0; i < ISDN_MAX_CHANNELS; i++)
-			kfree(dev->mdm.info[i].xmit_buf - 4);
-		isdn_cleanup_devfs();
-		devfs_unregister_chrdev(ISDN_MAJOR, "isdn");
-		vfree(dev);
-		return -EIO;
+		goto err_tty_modem;
 	}
 #endif                          /* CONFIG_ISDN_PPP */
 
@@ -2317,6 +2307,15 @@ static int __init isdn_init(void)
 #endif
 	isdn_info_update();
 	return 0;
+
+ err_tty_modem:
+	isdn_tty_exit();
+ err_cleanup_devfs:
+	isdn_cleanup_devfs();
+ err_vfree:
+	vfree(dev);
+ err:
+	return retval;
 }
 
 /*
@@ -2325,46 +2324,24 @@ static int __init isdn_init(void)
 static void __exit isdn_exit(void)
 {
 	unsigned long flags;
-	int i;
 
 #ifdef CONFIG_ISDN_PPP
 	isdn_ppp_cleanup();
 #endif
 	save_flags(flags);
 	cli();
-	if (isdn_net_rmall() < 0) {
-		printk(KERN_WARNING "isdn: net-device busy, remove cancelled\n");
-		restore_flags(flags);
-		return;
-	}
-	if (tty_unregister_driver(&dev->mdm.tty_modem)) {
-		printk(KERN_WARNING "isdn: ttyI-device busy, remove cancelled\n");
-		restore_flags(flags);
-		return;
-	}
-	if (tty_unregister_driver(&dev->mdm.cua_modem)) {
-		printk(KERN_WARNING "isdn: cui-device busy, remove cancelled\n");
-		restore_flags(flags);
-		return;
-	}
-	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
-		isdn_tty_cleanup_xmit(&dev->mdm.info[i]);
-		kfree(dev->mdm.info[i].xmit_buf - 4);
-#ifdef CONFIG_ISDN_TTY_FAX
-		kfree(dev->mdm.info[i].fax);
-#endif
-	}
-	if (devfs_unregister_chrdev(ISDN_MAJOR, "isdn") != 0) {
-		printk(KERN_WARNING "isdn: controldevice busy, remove cancelled\n");
-		restore_flags(flags);
-	} else {
-		isdn_cleanup_devfs();
-		del_timer(&dev->timer);
-		restore_flags(flags);
-		/* call vfree with interrupts enabled, else it will hang */
-		vfree(dev);
-		printk(KERN_NOTICE "ISDN-subsystem unloaded\n");
-	}
+	if (isdn_net_rmall() < 0)
+		BUG();
+
+	isdn_tty_exit();
+	if (devfs_unregister_chrdev(ISDN_MAJOR, "isdn"))
+		BUG();
+
+	isdn_cleanup_devfs();
+	del_timer(&dev->timer);
+	restore_flags(flags);
+	/* call vfree with interrupts enabled, else it will hang */
+	vfree(dev);
 }
 
 module_init(isdn_init);

drivers/isdn/i4l/isdn_tty.c

@@ -2015,10 +2015,10 @@ modem_write_profile(atemu * m)
 }
 
 int
-isdn_tty_modem_init(void)
+isdn_tty_init(void)
 {
 	modem *m;
-	int i;
+	int i, retval;
 	modem_info *info;
 
 	m = &dev->mdm;
@@ -2063,13 +2063,15 @@ isdn_tty_modem_init(void)
 	m->tty_modem.minor_start = 0;
 	m->cua_modem.subtype = ISDN_SERIAL_TYPE_CALLOUT;
 
-	if (tty_register_driver(&m->tty_modem)) {
+	retval = tty_register_driver(&m->tty_modem);
+	if (retval) {
 		printk(KERN_WARNING "isdn_tty: Couldn't register modem-device\n");
-		return -1;
+		goto err;
 	}
-	if (tty_register_driver(&m->cua_modem)) {
+	retval = tty_register_driver(&m->cua_modem);
+	if (retval) {
 		printk(KERN_WARNING "isdn_tty: Couldn't register modem-callout-device\n");
-		return -2;
+		goto err_unregister_tty;
 	}
 	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
 		info = &m->info[i];
@@ -2106,16 +2108,52 @@ isdn_tty_modem_init(void)
 #ifdef CONFIG_ISDN_AUDIO
 		skb_queue_head_init(&info->dtmf_queue);
 #endif
-		if (!(info->xmit_buf = kmalloc(ISDN_SERIAL_XMIT_MAX + 5, GFP_KERNEL))) {
+		info->xmit_buf = kmalloc(ISDN_SERIAL_XMIT_MAX + 5, GFP_KERNEL);
+		if (!info->xmit_buf) {
 			printk(KERN_ERR "Could not allocate modem xmit-buffer\n");
-			return -3;
+#ifdef CONFIG_ISDN_TTY_FAX
+			kfree(info->fax);
+#endif
+			goto err_unregister_cua;
 		}
 		/* Make room for T.70 header */
 		info->xmit_buf += 4;
 	}
 	return 0;
+
+ err_unregister_cua:
+	for (i--; i >= 0; i--) {
+		info = &m->info[i];
+#ifdef CONFIG_ISDN_TTY_FAX
+		kfree(info->fax);
+#endif
+		kfree(info->xmit_buf - 4);
+	}
+	tty_unregister_driver(&dev->mdm.cua_modem);
+ err_unregister_tty:
+	tty_unregister_driver(&dev->mdm.tty_modem);
+ err:
+	return retval;
 }
 
+void
+isdn_tty_exit(void)
+{
+	modem *m = &dev->mdm;
+	modem_info *info;
+	int i;
+
+	for (i = 0; i < ISDN_MAX_CHANNELS; i++) {
+		info = &m->info[i];
+		isdn_tty_cleanup_xmit(info);
+#ifdef CONFIG_ISDN_TTY_FAX
+		kfree(info->fax);
+#endif
+		kfree(info->xmit_buf - 4);
+	}
+	tty_unregister_driver(&dev->mdm.cua_modem);
+	tty_unregister_driver(&dev->mdm.tty_modem);
+}
 
 /*
  * isdn_tty_match_icall(char *MSN, atemu *tty_emulator, int dev_idx)

drivers/isdn/i4l/isdn_tty.h

@@ -105,7 +105,7 @@ extern void isdn_tty_modem_escape(void);
 extern void isdn_tty_modem_ring(void);
 extern void isdn_tty_carrier_timeout(void);
 extern void isdn_tty_modem_xmit(void);
-extern int isdn_tty_modem_init(void);
+extern int isdn_tty_init(void);
 extern void isdn_tty_readmodem(void);
 extern int isdn_tty_find_icall(int, int, setup_parm *);
 extern void isdn_tty_cleanup_xmit(modem_info *);
@@ -119,3 +119,6 @@ extern int isdn_tty_cmd_PLUSF_FAX(char **, modem_info *);
 extern int isdn_tty_fax_command(modem_info *, isdn_ctrl *);
 extern void isdn_tty_fax_bitorder(modem_info *, struct sk_buff *);
 #endif
+
+extern int isdn_tty_init(void);
+extern void isdn_tty_exit(void);