[PATCH] tty_driver refcounting

arch/um/drivers/* converted to dynamic allocation

arch/um/drivers/line.c

@@ -399,12 +399,17 @@ int line_remove(struct line *lines, int num, char *str)
 	return(line_setup(lines, num, config, 0));
 }
 
-void line_register_devfs(struct lines *set, struct line_driver *line_driver, 
-			 struct tty_driver *driver, struct line *lines,
+struct tty_driver *line_register_devfs(struct lines *set,
+			 struct line_driver *line_driver, 
+			 struct tty_operations *ops, struct line *lines,
 			 int nlines)
 {
 	int err, i;
 	char *from, *to;
+	struct tty_driver *driver = alloc_tty_driver(nlines);
+
+	if (!driver)
+		return NULL;
 
 	driver->driver_name = line_driver->name;
 	driver->name = line_driver->devfs_name;
@@ -412,11 +417,9 @@ void line_register_devfs(struct lines *set, struct line_driver *line_driver,
 	driver->minor_start = line_driver->minor_start;
 	driver->type = line_driver->type;
 	driver->subtype = line_driver->subtype;
-	driver->magic = TTY_DRIVER_MAGIC;
 	driver->flags = TTY_DRIVER_REAL_RAW;
-	driver->num = set->num;
-	driver->write_room = line_write_room;
 	driver->init_termios = tty_std_termios;
+	tty_set_operations(driver, ops);
 
 	if (tty_register_driver(driver))
 		panic("line_register_devfs : Couldn't register driver\n");
@@ -433,6 +436,7 @@ void line_register_devfs(struct lines *set, struct line_driver *line_driver,
 	}
 
 	mconsole_register_dev(&line_driver->mc);
+	return driver;
 }
 
 void lines_init(struct line *lines, int nlines)

arch/um/drivers/ssl.c

@@ -29,7 +29,7 @@ static int ssl_version = 1;
  * by the tty driver.
  */
 
-static struct tty_driver ssl_driver;
+static struct tty_driver *ssl_driver;
 
 #define NR_PORTS 64
 
@@ -189,7 +189,7 @@ void ssl_hangup(struct tty_struct *tty)
 {
 }
 
-static struct tty_driver ssl_driver = {
+static struct tty_operations ssl_ops = {
 	.open 	 		= ssl_open,
 	.close 	 		= ssl_close,
 	.write 	 		= ssl_write,
@@ -203,7 +203,8 @@ static struct tty_driver ssl_driver = {
 	.set_termios 		= ssl_set_termios,
 	.stop 	 		= ssl_stop,
 	.start 	 		= ssl_start,
-	.hangup 	 	= ssl_hangup
+	.hangup 	 	= ssl_hangup,
+	.write_room		= line_write_room,
 };
 
 /* Changed by ssl_init and referenced by ssl_exit, which are both serialized
@@ -218,8 +219,8 @@ int ssl_init(void)
 	printk(KERN_INFO "Initializing software serial port version %d\n", 
 	       ssl_version);
 
-	line_register_devfs(&lines, &driver, &ssl_driver, serial_lines, 
-			    sizeof(serial_lines)/sizeof(serial_lines[0]));
+	ssl_driver = line_register_devfs(&lines, &driver, &ssl_ops,
+		serial_lines, sizeof(serial_lines)/sizeof(serial_lines[0]));
 
 	lines_init(serial_lines, sizeof(serial_lines)/sizeof(serial_lines[0]));
 

arch/um/drivers/stdio_console.c

@@ -36,7 +36,7 @@
  * by the tty driver.
  */
 
-static struct tty_driver console_driver;
+static struct tty_driver *console_driver;
 
 static struct chan_ops init_console_ops = {
 	.type		= "you shouldn't see this",
@@ -165,8 +165,8 @@ int stdio_init(void)
 
 	printk(KERN_INFO "Initializing stdio console driver\n");
 
-	line_register_devfs(&console_lines, &driver, &console_driver, vts, 
-			    sizeof(vts)/sizeof(vts[0]));
+	console_driver = line_register_devfs(&console_lines, &driver,
+				&console_ops, vts, sizeof(vts)/sizeof(vts[0]));
 
 	lines_init(vts, sizeof(vts)/sizeof(vts[0]));
 
@@ -188,18 +188,19 @@ static void console_write(struct console *console, const char *string,
 	if(con_init_done) up(&vts[console->index].sem);
 }
 
-static struct tty_driver console_driver = {
+static struct tty_operations console_ops = {
 	.open 	 		= con_open,
 	.close 	 		= con_close,
 	.write 	 		= con_write,
 	.chars_in_buffer 	= chars_in_buffer,
-	.set_termios 		= set_termios
+	.set_termios 		= set_termios,
+	.write_room		= line_write_room,
 };
 
 static struct tty_driver *console_device(struct console *c, int *index)
 {
 	*index = c->index;
-	return &console_driver;
+	return console_driver;
 }
 
 static int console_setup(struct console *co, char *options)

arch/um/include/line.h

@@ -81,9 +81,10 @@ extern char *add_xterm_umid(char *base);
 extern int line_setup_irq(int fd, int input, int output, void *data);
 extern void line_close_chan(struct line *line);
 extern void line_disable(struct line *line, int current_irq);
-extern void line_register_devfs(struct lines *set, 
+extern struct tty_driver * line_register_devfs(struct lines *set, 
 				struct line_driver *line_driver, 
-				struct tty_driver *driver, struct line *lines,
+				struct tty_operations *driver,
+				struct line *lines,
 				int nlines);
 extern void lines_init(struct line *lines, int nlines);
 extern void close_lines(struct line *lines, int nlines);