[PATCH] tty_driver refcounting

drivers/s390/net/ctctty.c converted to dynamic allocation

diff --git a/drivers/s390/net/ctctty.c b/drivers/s390/net/ctctty.c
index f3fc20f6a6d7ee965d2f88cfbec3bd4921af6cbd..10f4c51f060150dbcbfae7fe6f163acec4830840 100644 (file)
--- a/drivers/s390/net/ctctty.c
+++ b/drivers/s390/net/ctctty.c
@@ -70,7 +70,7 @@ typedef struct {
 
 /* Description of one CTC-tty */
 typedef struct {
-  struct tty_driver  ctc_tty_device;              /* tty-device             */
+  struct tty_driver  *ctc_tty_device;             /* tty-device             */
   ctc_tty_info       info[CTC_TTY_MAX_DEVICES];           /* Private data           */
 } ctc_tty_driver;
 
@@ -1130,6 +1130,21 @@ ctc_tty_task(unsigned long arg)
        spin_unlock_irqrestore(&ctc_tty_lock, saveflags);
 }
 
+static struct tty_operations ctc_ops = {
+       .open = ctc_tty_open,
+       .close = ctc_tty_close,
+       .write = ctc_tty_write,
+       .flush_chars = ctc_tty_flush_chars,
+       .write_room = ctc_tty_write_room,
+       .chars_in_buffer = ctc_tty_chars_in_buffer,
+       .flush_buffer = ctc_tty_flush_buffer,
+       .ioctl = ctc_tty_ioctl,
+       .throttle = ctc_tty_throttle,
+       .unthrottle = ctc_tty_unthrottle,
+       .set_termios = ctc_tty_set_termios,
+       .hangup = ctc_tty_hangup,
+};
+
 int
 ctc_tty_init(void)
 {
@@ -1143,41 +1158,31 @@ ctc_tty_init(void)
                return -ENOMEM;
        }
        memset(driver, 0, sizeof(ctc_tty_driver));
-       device = &driver->ctc_tty_device;
+       device = alloc_tty_driver(CTC_TTY_MAX_DEVICES);
+       if (!device) {
+               kfree(driver);
+               printk(KERN_WARNING "Out of memory in ctc_tty_modem_init\n");
+               return -ENOMEM;
+       }
 
-       device->magic = TTY_DRIVER_MAGIC;
        device->devfs_name = "ctc/" CTC_TTY_NAME;
        device->name = CTC_TTY_NAME;
        device->major = CTC_TTY_MAJOR;
        device->minor_start = 0;
-       device->num = CTC_TTY_MAX_DEVICES;
        device->type = TTY_DRIVER_TYPE_SERIAL;
        device->subtype = SERIAL_TYPE_NORMAL;
        device->init_termios = tty_std_termios;
        device->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
        device->flags = TTY_DRIVER_REAL_RAW;
-       device->open = ctc_tty_open;
-       device->close = ctc_tty_close;
-       device->write = ctc_tty_write;
-       device->put_char = NULL;
-       device->flush_chars = ctc_tty_flush_chars;
-       device->write_room = ctc_tty_write_room;
-       device->chars_in_buffer = ctc_tty_chars_in_buffer;
-       device->flush_buffer = ctc_tty_flush_buffer;
-       device->ioctl = ctc_tty_ioctl;
-       device->throttle = ctc_tty_throttle;
-       device->unthrottle = ctc_tty_unthrottle;
-       device->set_termios = ctc_tty_set_termios;
-       device->stop = NULL;
-       device->start = NULL;
-       device->hangup = ctc_tty_hangup;
-       device->driver_name = "ctc_tty";
-
+       device->driver_name = "ctc_tty",
+       tty_set_operations(device, &ctc_ops);
        if (tty_register_driver(device)) {
                printk(KERN_WARNING "ctc_tty: Couldn't register serial-device\n");
+               put_tty_driver(device);
                kfree(driver);
                return -1;
        }
+       driver->ctc_tty_device = device;
        for (i = 0; i < CTC_TTY_MAX_DEVICES; i++) {
                info = &driver->info[i];
                init_MUTEX(&info->write_sem);
@@ -1258,8 +1263,9 @@ ctc_tty_cleanup(void) {
        
        spin_lock_irqsave(&ctc_tty_lock, saveflags);
        ctc_tty_shuttingdown = 1;
-       tty_unregister_driver(&driver->ctc_tty_device);
+       tty_unregister_driver(driver->ctc_tty_device);
        kfree(driver);
+       put_tty_driver(driver->ctc_tty_device);
        driver = NULL;
        spin_unlock_irqrestore(&ctc_tty_lock, saveflags);
 }