tty: Remove more special casing and out of place code

Carry on pushing code out of tty_io when it belongs to other drivers. I'm
not 100% happy with some of this and it will be worth revisiting some of the
exports later when the restructuring work is done.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

6 files changed, 195 insertions, 156 deletions

diff --git a/drivers/char/pty.c b/drivers/char/pty.c
index ec09c1cd4fe9..328e8ac12306 100644
--- a/drivers/char/pty.c
+++ b/drivers/char/pty.c
@@ -23,6 +23,7 @@
 #include <linux/mm.h>
 #include <linux/init.h>
 #include <linux/sysctl.h>
+#include <linux/device.h>
 
 #include <asm/uaccess.h>
 #include <asm/system.h>
@@ -332,6 +333,8 @@ int pty_limit = NR_UNIX98_PTY_DEFAULT;
 static int pty_limit_min = 0;
 static int pty_limit_max = NR_UNIX98_PTY_MAX;
 
+static struct cdev ptmx_cdev;
+
 static struct ctl_table pty_table[] = {
         {
                 .ctl_name       = PTY_MAX,
@@ -408,6 +411,70 @@ static const struct tty_operations ptm_unix98_ops = {
         .shutdown = pty_shutdown
 };
 
+
+/**
+ *      ptmx_open               -       open a unix 98 pty master
+ *      @inode: inode of device file
+ *      @filp: file pointer to tty
+ *
+ *      Allocate a unix98 pty master device from the ptmx driver.
+ *
+ *      Locking: tty_mutex protects the init_dev work. tty->count should
+ *              protect the rest.
+ *              allocated_ptys_lock handles the list of free pty numbers
+ */
+
+static int __ptmx_open(struct inode *inode, struct file *filp)
+{
+        struct tty_struct *tty;
+        int retval;
+        int index;
+
+        nonseekable_open(inode, filp);
+
+        /* find a device that is not in use. */
+        index = devpts_new_index();
+        if (index < 0)
+                return index;
+
+        mutex_lock(&tty_mutex);
+        retval = tty_init_dev(ptm_driver, index, &tty, 1);
+        mutex_unlock(&tty_mutex);
+
+        if (retval)
+                goto out;
+
+        set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
+        filp->private_data = tty;
+        file_move(filp, &tty->tty_files);
+
+        retval = devpts_pty_new(tty->link);
+        if (retval)
+                goto out1;
+
+        retval = ptm_driver->ops->open(tty, filp);
+        if (!retval)
+                return 0;
+out1:
+        tty_release_dev(filp);
+        return retval;
+out:
+        devpts_kill_index(index);
+        return retval;
+}
+
+static int ptmx_open(struct inode *inode, struct file *filp)
+{
+        int ret;
+
+        lock_kernel();
+        ret = __ptmx_open(inode, filp);
+        unlock_kernel();
+        return ret;
+}
+
+static struct file_operations ptmx_fops;
+
 static void __init unix98_pty_init(void)
 {
         ptm_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
@@ -459,7 +526,18 @@ static void __init unix98_pty_init(void)
 
         pty_table[1].data = &ptm_driver->refcount;
         register_sysctl_table(pty_root_table);
+
+        /* Now create the /dev/ptmx special device */
+        tty_default_fops(&ptmx_fops);
+        ptmx_fops.open = ptmx_open;
+
+        cdev_init(&ptmx_cdev, &ptmx_fops);
+        if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
+            register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
+                panic("Couldn't register /dev/ptmx driver\n");
+        device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
 }
+
 #else
 static inline void unix98_pty_init(void) { }
 #endif
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index f91704d57a4e..fdcc43c8ef3c 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -49,7 +49,7 @@
  * implement CONFIG_VT and generalize console device interface.
  *      -- Marko Kohtala <Marko.Kohtala@hut.fi>, March 97
  *
- * Rewrote init_dev and release_dev to eliminate races.
+ * Rewrote tty_init_dev and tty_release_dev to eliminate races.
  *      -- Bill Hawes <whawes@star.net>, June 97
  *
  * Added devfs support.
@@ -136,11 +136,6 @@ LIST_HEAD(tty_drivers);			/* linked list of tty drivers */
 DEFINE_MUTEX(tty_mutex);
 EXPORT_SYMBOL(tty_mutex);
 
-#ifdef CONFIG_UNIX98_PTYS
-extern struct tty_driver *ptm_driver;   /* Unix98 pty masters; for /dev/ptmx */
-static int ptmx_open(struct inode *, struct file *);
-#endif
-
 static void initialize_tty_struct(struct tty_struct *tty);
 
 static ssize_t tty_read(struct file *, char __user *, size_t, loff_t *);
@@ -425,20 +420,6 @@ static const struct file_operations tty_fops = {
         .fasync         = tty_fasync,
 };
 
-#ifdef CONFIG_UNIX98_PTYS
-static const struct file_operations ptmx_fops = {
-        .llseek         = no_llseek,
-        .read           = tty_read,
-        .write          = tty_write,
-        .poll           = tty_poll,
-        .unlocked_ioctl = tty_ioctl,
-        .compat_ioctl   = tty_compat_ioctl,
-        .open           = ptmx_open,
-        .release        = tty_release,
-        .fasync         = tty_fasync,
-};
-#endif
-
 static const struct file_operations console_fops = {
         .llseek         = no_llseek,
         .read           = tty_read,
@@ -1224,7 +1205,7 @@ static void tty_line_name(struct tty_driver *driver, int index, char *p)
 }
 
 /**
- *      init_dev                -       initialise a tty device
+ *      tty_init_dev            -       initialise a tty device
  *      @driver: tty driver we are opening a device on
  *      @idx: device index
  *      @ret_tty: returned tty structure
@@ -1248,7 +1229,7 @@ static void tty_line_name(struct tty_driver *driver, int index, char *p)
  * relaxed for the (most common) case of reopening a tty.
  */
 
-static int init_dev(struct tty_driver *driver, int idx,
+int tty_init_dev(struct tty_driver *driver, int idx,
         struct tty_struct **ret_tty, int first_ok)
 {
         struct tty_struct *tty, *o_tty;
@@ -1269,8 +1250,8 @@ static int init_dev(struct tty_driver *driver, int idx,
                         goto end_init;
                 }
                 /*
-                 * It's safe from now on because init_dev() is called with
-                 * tty_mutex held and release_dev() won't change tty->count
+                 * It's safe from now on because tty_init_dev() is called with
+                 * tty_mutex held and tty_release_dev() won't change tty->count
                  * or tty->flags without having to grab tty_mutex
                  */
                 if (tty && driver->subtype == PTY_TYPE_MASTER)
@@ -1449,7 +1430,7 @@ fast_track:
 
         /* FIXME */
         if (!test_bit(TTY_LDISC, &tty->flags))
-                printk(KERN_ERR "init_dev but no ldisc\n");
+                printk(KERN_ERR "tty_init_dev but no ldisc\n");
 success:
         *ret_tty = tty;
 
@@ -1476,7 +1457,7 @@ fail_no_mem:
         /* call the tty release_tty routine to clean out this slot */
 release_mem_out:
         if (printk_ratelimit())
-                printk(KERN_INFO "init_dev: ldisc open failed, "
+                printk(KERN_INFO "tty_init_dev: ldisc open failed, "
                                  "clearing slot %d\n", idx);
         release_tty(tty, idx);
         goto end_init;
@@ -1587,7 +1568,7 @@ static void release_tty(struct tty_struct *tty, int idx)
  * WSH 09/09/97: rewritten to avoid some nasty race conditions that could
  * lead to double frees or releasing memory still in use.
  */
-static void release_dev(struct file *filp)
+void tty_release_dev(struct file *filp)
 {
         struct tty_struct *tty, *o_tty;
         int     pty_master, tty_closing, o_tty_closing, do_sleep;
@@ -1597,10 +1578,10 @@ static void release_dev(struct file *filp)
 
         tty = (struct tty_struct *)filp->private_data;
         if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode,
-                                                        "release_dev"))
+                                                        "tty_release_dev"))
                 return;
 
-        check_tty_count(tty, "release_dev");
+        check_tty_count(tty, "tty_release_dev");
 
         tty_fasync(-1, filp, 0);
 
@@ -1612,24 +1593,24 @@ static void release_dev(struct file *filp)
 
 #ifdef TTY_PARANOIA_CHECK
         if (idx < 0 || idx >= tty->driver->num) {
-                printk(KERN_DEBUG "release_dev: bad idx when trying to "
+                printk(KERN_DEBUG "tty_release_dev: bad idx when trying to "
                                   "free (%s)\n", tty->name);
                 return;
         }
         if (!(tty->driver->flags & TTY_DRIVER_DEVPTS_MEM)) {
                 if (tty != tty->driver->ttys[idx]) {
-                        printk(KERN_DEBUG "release_dev: driver.table[%d] not tty "
+                        printk(KERN_DEBUG "tty_release_dev: driver.table[%d] not tty "
                                "for (%s)\n", idx, tty->name);
                         return;
                 }
                 if (tty->termios != tty->driver->termios[idx]) {
-                        printk(KERN_DEBUG "release_dev: driver.termios[%d] not termios "
+                        printk(KERN_DEBUG "tty_release_dev: driver.termios[%d] not termios "
                                "for (%s)\n",
                                idx, tty->name);
                         return;
                 }
                 if (tty->termios_locked != tty->driver->termios_locked[idx]) {
-                        printk(KERN_DEBUG "release_dev: driver.termios_locked[%d] not "
+                        printk(KERN_DEBUG "tty_release_dev: driver.termios_locked[%d] not "
                                "termios_locked for (%s)\n",
                                idx, tty->name);
                         return;
@@ -1638,7 +1619,7 @@ static void release_dev(struct file *filp)
 #endif
 
 #ifdef TTY_DEBUG_HANGUP
-        printk(KERN_DEBUG "release_dev of %s (tty count=%d)...",
+        printk(KERN_DEBUG "tty_release_dev of %s (tty count=%d)...",
                tty_name(tty, buf), tty->count);
 #endif
 
@@ -1646,26 +1627,26 @@ static void release_dev(struct file *filp)
         if (tty->driver->other &&
              !(tty->driver->flags & TTY_DRIVER_DEVPTS_MEM)) {
                 if (o_tty != tty->driver->other->ttys[idx]) {
-                        printk(KERN_DEBUG "release_dev: other->table[%d] "
+                        printk(KERN_DEBUG "tty_release_dev: other->table[%d] "
                                           "not o_tty for (%s)\n",
                                idx, tty->name);
                         return;
                 }
                 if (o_tty->termios != tty->driver->other->termios[idx]) {
-                        printk(KERN_DEBUG "release_dev: other->termios[%d] "
+                        printk(KERN_DEBUG "tty_release_dev: other->termios[%d] "
                                           "not o_termios for (%s)\n",
                                idx, tty->name);
                         return;
                 }
                 if (o_tty->termios_locked !=
                       tty->driver->other->termios_locked[idx]) {
-                        printk(KERN_DEBUG "release_dev: other->termios_locked["
+                        printk(KERN_DEBUG "tty_release_dev: other->termios_locked["
                                           "%d] not o_termios_locked for (%s)\n",
                                idx, tty->name);
                         return;
                 }
                 if (o_tty->link != tty) {
-                        printk(KERN_DEBUG "release_dev: bad pty pointers\n");
+                        printk(KERN_DEBUG "tty_release_dev: bad pty pointers\n");
                         return;
                 }
         }
@@ -1723,7 +1704,7 @@ static void release_dev(struct file *filp)
                 if (!do_sleep)
                         break;
 
-                printk(KERN_WARNING "release_dev: %s: read/write wait queue "
+                printk(KERN_WARNING "tty_release_dev: %s: read/write wait queue "
                                     "active!\n", tty_name(tty, buf));
                 mutex_unlock(&tty_mutex);
                 schedule();
@@ -1736,14 +1717,14 @@ static void release_dev(struct file *filp)
          */
         if (pty_master) {
                 if (--o_tty->count < 0) {
-                        printk(KERN_WARNING "release_dev: bad pty slave count "
+                        printk(KERN_WARNING "tty_release_dev: bad pty slave count "
                                             "(%d) for %s\n",
                                o_tty->count, tty_name(o_tty, buf));
                         o_tty->count = 0;
                 }
         }
         if (--tty->count < 0) {
-                printk(KERN_WARNING "release_dev: bad tty->count (%d) for %s\n",
+                printk(KERN_WARNING "tty_release_dev: bad tty->count (%d) for %s\n",
                        tty->count, tty_name(tty, buf));
                 tty->count = 0;
         }
@@ -1825,7 +1806,7 @@ static void release_dev(struct file *filp)
  *      The termios state of a pty is reset on first open so that
  *      settings don't persist across reuse.
  *
- *      Locking: tty_mutex protects tty, get_tty_driver and init_dev work.
+ *      Locking: tty_mutex protects tty, get_tty_driver and tty_init_dev work.
  *               tty->count should protect the rest.
  *               ->siglock protects ->signal/->sighand
  */
@@ -1889,7 +1870,7 @@ retry_open:
                 return -ENODEV;
         }
 got_driver:
-        retval = init_dev(driver, index, &tty, 0);
+        retval = tty_init_dev(driver, index, &tty, 0);
         mutex_unlock(&tty_mutex);
         if (retval)
                 return retval;
@@ -1920,7 +1901,7 @@ got_driver:
                 printk(KERN_DEBUG "error %d in opening %s...", retval,
                        tty->name);
 #endif
-                release_dev(filp);
+                tty_release_dev(filp);
                 if (retval != -ERESTARTSYS)
                         return retval;
                 if (signal_pending(current))
@@ -1959,69 +1940,6 @@ static int tty_open(struct inode *inode, struct file *filp)
 
 
 
-#ifdef CONFIG_UNIX98_PTYS
-/**
- *      ptmx_open               -       open a unix 98 pty master
- *      @inode: inode of device file
- *      @filp: file pointer to tty
- *
- *      Allocate a unix98 pty master device from the ptmx driver.
- *
- *      Locking: tty_mutex protects theinit_dev work. tty->count should
- *              protect the rest.
- *              allocated_ptys_lock handles the list of free pty numbers
- */
-
-static int __ptmx_open(struct inode *inode, struct file *filp)
-{
-        struct tty_struct *tty;
-        int retval;
-        int index;
-
-        nonseekable_open(inode, filp);
-
-        /* find a device that is not in use. */
-        index = devpts_new_index();
-        if (index < 0)
-                return index;
-
-        mutex_lock(&tty_mutex);
-        retval = init_dev(ptm_driver, index, &tty, 1);
-        mutex_unlock(&tty_mutex);
-
-        if (retval)
-                goto out;
-
-        set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
-        filp->private_data = tty;
-        file_move(filp, &tty->tty_files);
-
-        retval = devpts_pty_new(tty->link);
-        if (retval)
-                goto out1;
-
-        check_tty_count(tty, "ptmx_open");
-        retval = ptm_driver->ops->open(tty, filp);
-        if (!retval)
-                return 0;
-out1:
-        release_dev(filp);
-        return retval;
-out:
-        devpts_kill_index(index);
-        return retval;
-}
-
-static int ptmx_open(struct inode *inode, struct file *filp)
-{
-        int ret;
-
-        lock_kernel();
-        ret = __ptmx_open(inode, filp);
-        unlock_kernel();
-        return ret;
-}
-#endif
 
 /**
  *      tty_release             -       vfs callback for close
@@ -2032,13 +1950,13 @@ static int ptmx_open(struct inode *inode, struct file *filp)
  *      this tty. There may however be several such references.
  *
  *      Locking:
- *              Takes bkl. See release_dev
+ *              Takes bkl. See tty_release_dev
  */
 
 static int tty_release(struct inode *inode, struct file *filp)
 {
         lock_kernel();
-        release_dev(filp);
+        tty_release_dev(filp);
         unlock_kernel();
         return 0;
 }
@@ -2932,7 +2850,7 @@ int tty_put_char(struct tty_struct *tty, unsigned char ch)
 
 EXPORT_SYMBOL_GPL(tty_put_char);
 
-static struct class *tty_class;
+struct class *tty_class;
 
 /**
  *      tty_register_device - register a tty device
@@ -3197,6 +3115,11 @@ struct tty_struct *get_current_tty(void)
 }
 EXPORT_SYMBOL_GPL(get_current_tty);
 
+void tty_default_fops(struct file_operations *fops)
+{
+        *fops = tty_fops;
+}
+
 /*
  * Initialize the console device. This is called *early*, so
  * we can't necessarily depend on lots of kernel help here.
@@ -3234,12 +3157,6 @@ postcore_initcall(tty_class_init);
 /* 3/2004 jmc: why do these devices exist? */
 
 static struct cdev tty_cdev, console_cdev;
-#ifdef CONFIG_UNIX98_PTYS
-static struct cdev ptmx_cdev;
-#endif
-#ifdef CONFIG_VT
-static struct cdev vc0_cdev;
-#endif
 
 /*
  * Ok, now we can initialize the rest of the tty devices and can count
@@ -3251,32 +3168,18 @@ static int __init tty_init(void)
         if (cdev_add(&tty_cdev, MKDEV(TTYAUX_MAJOR, 0), 1) ||
             register_chrdev_region(MKDEV(TTYAUX_MAJOR, 0), 1, "/dev/tty") < 0)
                 panic("Couldn't register /dev/tty driver\n");
-        device_create_drvdata(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 0), NULL,
+        device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 0), NULL,
                               "tty");
 
         cdev_init(&console_cdev, &console_fops);
         if (cdev_add(&console_cdev, MKDEV(TTYAUX_MAJOR, 1), 1) ||
             register_chrdev_region(MKDEV(TTYAUX_MAJOR, 1), 1, "/dev/console") < 0)
                 panic("Couldn't register /dev/console driver\n");
-        device_create_drvdata(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 1), NULL,
+        device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 1), NULL,
                               "console");
 
-#ifdef CONFIG_UNIX98_PTYS
-        cdev_init(&ptmx_cdev, &ptmx_fops);
-        if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
-            register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
-                panic("Couldn't register /dev/ptmx driver\n");
-        device_create_drvdata(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
-#endif
-
 #ifdef CONFIG_VT
-        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_drvdata(tty_class, NULL, MKDEV(TTY_MAJOR, 0), NULL, "tty0");
-
-        vty_init();
+        vty_init(&console_fops);
 #endif
         return 0;
 }
diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c
index 30670851e51a..14cc19c344cc 100644
--- a/drivers/char/tty_ioctl.c
+++ b/drivers/char/tty_ioctl.c
@@ -40,6 +40,15 @@
 #define TERMIOS_OLD     8
 
 
+/**
+ *      tty_chars_in_buffer     -       characters pending
+ *      @tty: terminal
+ *
+ *      Return the number of bytes of data in the device private
+ *      output queue. If no private method is supplied there is assumed
+ *      to be no queue on the device.
+ */
+
 int tty_chars_in_buffer(struct tty_struct *tty)
 {
         if (tty->ops->chars_in_buffer)
@@ -47,26 +56,49 @@ int tty_chars_in_buffer(struct tty_struct *tty)
         else
                 return 0;
 }
-
 EXPORT_SYMBOL(tty_chars_in_buffer);
 
+/**
+ *      tty_write_room          -       write queue space
+ *      @tty: terminal
+ *
+ *      Return the number of bytes that can be queued to this device
+ *      at the present time. The result should be treated as a guarantee
+ *      and the driver cannot offer a value it later shrinks by more than
+ *      the number of bytes written. If no method is provided 2K is always
+ *      returned and data may be lost as there will be no flow control.
+ */
+ 
 int tty_write_room(struct tty_struct *tty)
 {
         if (tty->ops->write_room)
                 return tty->ops->write_room(tty);
         return 2048;
 }
-
 EXPORT_SYMBOL(tty_write_room);
 
+/**
+ *      tty_driver_flush_buffer -       discard internal buffer
+ *      @tty: terminal
+ *
+ *      Discard the internal output buffer for this device. If no method
+ *      is provided then either the buffer cannot be hardware flushed or
+ *      there is no buffer driver side.
+ */
 void tty_driver_flush_buffer(struct tty_struct *tty)
 {
         if (tty->ops->flush_buffer)
                 tty->ops->flush_buffer(tty);
 }
-
 EXPORT_SYMBOL(tty_driver_flush_buffer);
 
+/**
+ *      tty_throttle            -       flow control
+ *      @tty: terminal
+ *
+ *      Indicate that a tty should stop transmitting data down the stack.
+ */
+
 void tty_throttle(struct tty_struct *tty)
 {
         /* check TTY_THROTTLED first so it indicates our state */
@@ -76,6 +108,13 @@ void tty_throttle(struct tty_struct *tty)
 }
 EXPORT_SYMBOL(tty_throttle);
 
+/**
+ *      tty_unthrottle          -       flow control
+ *      @tty: terminal
+ *
+ *      Indicate that a tty may continue transmitting data down the stack.
+ */
+
 void tty_unthrottle(struct tty_struct *tty)
 {
         if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) &&
@@ -112,6 +151,11 @@ void tty_wait_until_sent(struct tty_struct *tty, long timeout)
 }
 EXPORT_SYMBOL(tty_wait_until_sent);
 
+
+/*
+ *              Termios Helper Methods
+ */
+
 static void unset_locked_termios(struct ktermios *termios,
                                  struct ktermios *old,
                                  struct ktermios *locked)
@@ -346,6 +390,16 @@ void tty_termios_encode_baud_rate(struct ktermios *termios,
 }
 EXPORT_SYMBOL_GPL(tty_termios_encode_baud_rate);
 
+/**
+ *      tty_encode_baud_rate            -       set baud rate of the tty
+ *      @ibaud: input baud rate
+ *      @obad: output baud rate
+ *
+ *      Update the current termios data for the tty with the new speed
+ *      settings. The caller must hold the termios_mutex for the tty in
+ *      question.
+ */
+
 void tty_encode_baud_rate(struct tty_struct *tty, speed_t ibaud, speed_t obaud)
 {
         tty_termios_encode_baud_rate(tty->termios, ibaud, obaud);
@@ -430,7 +484,7 @@ EXPORT_SYMBOL(tty_termios_hw_change);
  *      is a bit of layering violation here with n_tty in terms of the
  *      internal knowledge of this function.
  *
- *      Locking: termios_sem
+ *      Locking: termios_mutex
  */
 
 static void change_termios(struct tty_struct *tty, struct ktermios *new_termios)
@@ -508,7 +562,7 @@ static void change_termios(struct tty_struct *tty, struct ktermios *new_termios)
  *      functions before using change_termios to do the actual changes.
  *
  *      Locking:
- *              Called functions take ldisc and termios_sem locks
+ *              Called functions take ldisc and termios_mutex locks
  */
 
 static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
@@ -715,7 +769,7 @@ static void set_sgflags(struct ktermios *termios, int flags)
  *      Updates a terminal from the legacy BSD style terminal information
  *      structure.
  *
- *      Locking: termios_sem
+ *      Locking: termios_mutex
  */
 
 static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb)
diff --git a/drivers/char/vt.c b/drivers/char/vt.c
index 37a45db5bae0..57029fefd64a 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
 
@@ -2352,8 +2352,6 @@ rescan_last_byte:
         FLUSH
         console_conditional_schedule();
         release_console_sem();
-
-out:
         notify_update(vc);
         return n;
 #undef FLUSH
@@ -2784,13 +2782,6 @@ 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)
 {
         /* Nothing to do - we defer to shutdown */
@@ -2932,8 +2923,16 @@ static const struct tty_operations con_ops = {
         .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);
@@ -2952,7 +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
@@ -3446,7 +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);
@@ -3557,7 +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);
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 6e39c705b9b6..6cc7ccc93c69 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -314,6 +314,8 @@ extern int kmsg_redirect;
 extern void console_init(void);
 extern int vcs_init(void);
 
+extern struct class *tty_class;
+
 /**
  *      tty_kref_get            -       get a tty reference
  *      @tty: tty device
@@ -398,6 +400,10 @@ extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
 extern dev_t tty_devnum(struct tty_struct *tty);
 extern void proc_clear_tty(struct task_struct *p);
 extern struct tty_struct *get_current_tty(void);
+extern void tty_default_fops(struct file_operations *fops);
+extern int tty_init_dev(struct tty_driver *driver, int idx,
+                        struct tty_struct **ret_tty, int first_ok);
+extern void tty_release_dev(struct file *filp);
 
 extern struct mutex tty_mutex;
 
diff --git a/include/linux/vt_kern.h b/include/linux/vt_kern.h
index 1cbd0a7db4e6..2f1113467f70 100644
--- a/include/linux/vt_kern.h
+++ b/include/linux/vt_kern.h
@@ -96,7 +96,7 @@ void change_console(struct vc_data *new_vc);
 void reset_vc(struct vc_data *vc);
 extern int unbind_con_driver(const struct consw *csw, int first, int last,
                              int deflt);
-int vty_init(void);
+int vty_init(const struct file_operations *console_fops);
 
 /*
  * vc_screen.c shares this temporary buffer with the console write code so that