1 files changed, 31 insertions, 53 deletions

diff --git a/drivers/char/vt.c b/drivers/char/vt.c
index 60359c3..57029fe 100644
--- a/drivers/char/vt.c
+++ b/drivers/char/vt.c
@@ -100,10 +100,10 @@
 #include <linux/font.h>
 #include <linux/bitops.h>
 #include <linux/notifier.h>
-
-#include <asm/io.h>
+#include <linux/device.h>
+#include <linux/io.h>
 #include <asm/system.h>
-#include <asm/uaccess.h>
+#include <linux/uaccess.h>
 
 #define MAX_NR_CON_DRIVER 16
 
@@ -2136,27 +2136,9 @@ static int do_con_write(struct tty_struct *tty, const unsigned char *buf, int co
 	    release_console_sem();
 	    return 0;
 	}
-	release_console_sem();
-
 	orig_buf = buf;
 	orig_count = count;
 
-	/* At this point 'buf' is guaranteed to be a kernel buffer
-	 * and therefore no access to userspace (and therefore sleeping)
-	 * will be needed.  The con_buf_mtx serializes all tty based
-	 * console rendering and vcs write/read operations.  We hold
-	 * the console spinlock during the entire write.
-	 */
-
-	acquire_console_sem();
-
-	vc = tty->driver_data;
-	if (vc == NULL) {
-		printk(KERN_ERR "vt: argh, driver_data _became_ NULL !\n");
-		release_console_sem();
-		goto out;
-	}
-
 	himask = vc->vc_hi_font_mask;
 	charmask = himask ? 0x1ff : 0xff;
 
@@ -2370,8 +2352,6 @@ rescan_last_byte:
 	FLUSH
 	console_conditional_schedule();
 	release_console_sem();
-
-out:
 	notify_update(vc);
 	return n;
 #undef FLUSH
@@ -2583,8 +2563,6 @@ int tioclinux(struct tty_struct *tty, unsigned long arg)
 	int lines;
 	int ret;
 
-	if (tty->driver->type != TTY_DRIVER_TYPE_CONSOLE)
-		return -EINVAL;
 	if (current->signal->tty != tty && !capable(CAP_SYS_ADMIN))
 		return -EPERM;
 	if (get_user(type, p))
@@ -2778,6 +2756,12 @@ static int con_open(struct tty_struct *tty, struct file *filp)
 		ret = vc_allocate(currcons);
 		if (ret == 0) {
 			struct vc_data *vc = vc_cons[currcons].d;
+
+			/* Still being freed */
+			if (vc->vc_tty) {
+				release_console_sem();
+				return -ERESTARTSYS;
+			}
 			tty->driver_data = vc;
 			vc->vc_tty = tty;
 
@@ -2798,34 +2782,20 @@ static int con_open(struct tty_struct *tty, struct file *filp)
 	return ret;
 }
 
-/*
- * We take tty_mutex in here to prevent another thread from coming in via init_dev
- * and taking a ref against the tty while we're in the process of forgetting
- * about it and cleaning things up.
- *
- * This is because vcs_remove_sysfs() can sleep and will drop the BKL.
- */
 static void con_close(struct tty_struct *tty, struct file *filp)
 {
-	mutex_lock(&tty_mutex);
-	acquire_console_sem();
-	if (tty && tty->count == 1) {
-		struct vc_data *vc = tty->driver_data;
+	/* Nothing to do - we defer to shutdown */
+}
 
-		if (vc)
-			vc->vc_tty = NULL;
-		tty->driver_data = NULL;
-		vcs_remove_sysfs(tty);
-		release_console_sem();
-		mutex_unlock(&tty_mutex);
-		/*
-		 * tty_mutex is released, but we still hold BKL, so there is
-		 * still exclusion against init_dev()
-		 */
-		return;
-	}
+static void con_shutdown(struct tty_struct *tty)
+{
+	struct vc_data *vc = tty->driver_data;
+	BUG_ON(vc == NULL);
+	acquire_console_sem();
+	vc->vc_tty = NULL;
+	vcs_remove_sysfs(tty);
 	release_console_sem();
-	mutex_unlock(&tty_mutex);
+	tty_shutdown(tty);
 }
 
 static int default_italic_color    = 2; // green (ASCII)
@@ -2950,10 +2920,19 @@ static const struct tty_operations con_ops = {
 	.throttle = con_throttle,
 	.unthrottle = con_unthrottle,
 	.resize = vt_resize,
+	.shutdown = con_shutdown
 };
 
-int __init vty_init(void)
+static struct cdev vc0_cdev;
+
+int __init vty_init(const struct file_operations *console_fops)
 {
+	cdev_init(&vc0_cdev, console_fops);
+	if (cdev_add(&vc0_cdev, MKDEV(TTY_MAJOR, 0), 1) ||
+	    register_chrdev_region(MKDEV(TTY_MAJOR, 0), 1, "/dev/vc/0") < 0)
+		panic("Couldn't register /dev/tty0 driver\n");
+	device_create(tty_class, NULL, MKDEV(TTY_MAJOR, 0), NULL, "tty0");
+
 	vcs_init();
 
 	console_driver = alloc_tty_driver(MAX_NR_CONSOLES);
@@ -2972,7 +2951,6 @@ int __init vty_init(void)
 	tty_set_operations(console_driver, &con_ops);
 	if (tty_register_driver(console_driver))
 		panic("Couldn't register console driver\n");
-
 	kbd_init();
 	console_map_init();
 #ifdef CONFIG_PROM_CONSOLE
@@ -3466,7 +3444,7 @@ int register_con_driver(const struct consw *csw, int first, int last)
 	if (retval)
 		goto err;
 
-	con_driver->dev = device_create_drvdata(vtconsole_class, NULL,
+	con_driver->dev = device_create(vtconsole_class, NULL,
 						MKDEV(0, con_driver->node),
 						NULL, "vtcon%i",
 						con_driver->node);
@@ -3577,7 +3555,7 @@ static int __init vtconsole_class_init(void)
 		struct con_driver *con = &registered_con_driver[i];
 
 		if (con->con && !con->dev) {
-			con->dev = device_create_drvdata(vtconsole_class, NULL,
+			con->dev = device_create(vtconsole_class, NULL,
 							 MKDEV(0, con->node),
 							 NULL, "vtcon%i",
 							 con->node);