1 files changed, 37 insertions, 55 deletions

diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 8b2a59969868..a1143238feca 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -102,7 +102,6 @@
 #include <linux/kbd_kern.h>
 #include <linux/vt_kern.h>
 #include <linux/selection.h>
-#include <linux/devfs_fs_kernel.h>
 
 #include <linux/kmod.h>
 
@@ -267,7 +266,6 @@ static struct tty_buffer *tty_buffer_alloc(size_t size)
         p->used = 0;
         p->size = size;
         p->next = NULL;
-        p->active = 0;
         p->commit = 0;
         p->read = 0;
         p->char_buf_ptr = (char *)(p->data);
@@ -327,10 +325,9 @@ int tty_buffer_request_room(struct tty_struct *tty, size_t size)
         /* OPTIMISATION: We could keep a per tty "zero" sized buffer to
            remove this conditional if its worth it. This would be invisible
            to the callers */
-        if ((b = tty->buf.tail) != NULL) {
+        if ((b = tty->buf.tail) != NULL)
                 left = b->size - b->used;
-                b->active = 1;
-        } else
+        else
                 left = 0;
 
         if (left < size) {
@@ -338,12 +335,10 @@ int tty_buffer_request_room(struct tty_struct *tty, size_t size)
                 if ((n = tty_buffer_find(tty, size)) != NULL) {
                         if (b != NULL) {
                                 b->next = n;
-                                b->active = 0;
                                 b->commit = b->used;
                         } else
                                 tty->buf.head = n;
                         tty->buf.tail = n;
-                        n->active = 1;
                 } else
                         size = left;
         }
@@ -404,10 +399,8 @@ void tty_schedule_flip(struct tty_struct *tty)
 {
         unsigned long flags;
         spin_lock_irqsave(&tty->buf.lock, flags);
-        if (tty->buf.tail != NULL) {
-                tty->buf.tail->active = 0;
+        if (tty->buf.tail != NULL)
                 tty->buf.tail->commit = tty->buf.tail->used;
-        }
         spin_unlock_irqrestore(&tty->buf.lock, flags);
         schedule_delayed_work(&tty->buf.work, 1);
 }
@@ -784,11 +777,8 @@ restart:
         }
 
         clear_bit(TTY_LDISC, &tty->flags);
-        clear_bit(TTY_DONT_FLIP, &tty->flags);
-        if (o_tty) {
+        if (o_tty)
                 clear_bit(TTY_LDISC, &o_tty->flags);
-                clear_bit(TTY_DONT_FLIP, &o_tty->flags);
-        }
         spin_unlock_irqrestore(&tty_ldisc_lock, flags);
 
         /*
@@ -1955,7 +1945,6 @@ static void release_dev(struct file * filp)
          * race with the set_ldisc code path.
          */
         clear_bit(TTY_LDISC, &tty->flags);
-        clear_bit(TTY_DONT_FLIP, &tty->flags);
         cancel_delayed_work(&tty->buf.work);
 
         /*
@@ -2621,10 +2610,9 @@ int tty_ioctl(struct inode * inode, struct file * file,
                         tty->driver->break_ctl(tty, 0);
                         return 0;
                 case TCSBRK:   /* SVID version: non-zero arg --> no break */
-                        /*
-                         * XXX is the above comment correct, or the
-                         * code below correct?  Is this ioctl used at
-                         * all by anyone?
+                        /* non-zero arg means wait for all output data
+                         * to be sent (performed above) but don't send break.
+                         * This is used by the tcdrain() termios function.
                          */
                         if (!arg)
                                 return send_break(tty, 250);
@@ -2776,8 +2764,7 @@ static void flush_to_ldisc(void *private_)
         struct tty_struct *tty = (struct tty_struct *) private_;
         unsigned long   flags;
         struct tty_ldisc *disc;
-        struct tty_buffer *tbuf;
-        int count;
+        struct tty_buffer *tbuf, *head;
         char *char_buf;
         unsigned char *flag_buf;
 
@@ -2785,32 +2772,37 @@ static void flush_to_ldisc(void *private_)
         if (disc == NULL)       /*  !TTY_LDISC */
                 return;
 
-        if (test_bit(TTY_DONT_FLIP, &tty->flags)) {
-                /*
-                 * Do it after the next timer tick:
-                 */
-                schedule_delayed_work(&tty->buf.work, 1);
-                goto out;
-        }
         spin_lock_irqsave(&tty->buf.lock, flags);
-        while((tbuf = tty->buf.head) != NULL) {
-                while ((count = tbuf->commit - tbuf->read) != 0) {
-                        char_buf = tbuf->char_buf_ptr + tbuf->read;
-                        flag_buf = tbuf->flag_buf_ptr + tbuf->read;
-                        tbuf->read += count;
+        head = tty->buf.head;
+        if (head != NULL) {
+                tty->buf.head = NULL;
+                for (;;) {
+                        int count = head->commit - head->read;
+                        if (!count) {
+                                if (head->next == NULL)
+                                        break;
+                                tbuf = head;
+                                head = head->next;
+                                tty_buffer_free(tty, tbuf);
+                                continue;
+                        }
+                        if (!tty->receive_room) {
+                                schedule_delayed_work(&tty->buf.work, 1);
+                                break;
+                        }
+                        if (count > tty->receive_room)
+                                count = tty->receive_room;
+                        char_buf = head->char_buf_ptr + head->read;
+                        flag_buf = head->flag_buf_ptr + head->read;
+                        head->read += count;
                         spin_unlock_irqrestore(&tty->buf.lock, flags);
                         disc->receive_buf(tty, char_buf, flag_buf, count);
                         spin_lock_irqsave(&tty->buf.lock, flags);
                 }
-                if (tbuf->active)
-                        break;
-                tty->buf.head = tbuf->next;
-                if (tty->buf.head == NULL)
-                        tty->buf.tail = NULL;
-                tty_buffer_free(tty, tbuf);
+                tty->buf.head = head;
         }
         spin_unlock_irqrestore(&tty->buf.lock, flags);
-out:
+
         tty_ldisc_deref(disc);
 }
 
@@ -2903,10 +2895,8 @@ void tty_flip_buffer_push(struct tty_struct *tty)
 {
         unsigned long flags;
         spin_lock_irqsave(&tty->buf.lock, flags);
-        if (tty->buf.tail != NULL) {
-                tty->buf.tail->active = 0;
+        if (tty->buf.tail != NULL)
                 tty->buf.tail->commit = tty->buf.tail->used;
-        }
         spin_unlock_irqrestore(&tty->buf.lock, flags);
 
         if (tty->low_latency)
@@ -2964,8 +2954,8 @@ static struct class *tty_class;
  * Returns a pointer to the class device (or ERR_PTR(-EFOO) on error).
  *
  * This call is required to be made to register an individual tty device if
- * the tty driver's flags have the TTY_DRIVER_NO_DEVFS bit set.  If that
- * bit is not set, this function should not be called.
+ * the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set.  If that
+ * bit is not set, this function should not be called by a tty driver.
  */
 struct class_device *tty_register_device(struct tty_driver *driver,
                                          unsigned index, struct device *device)
@@ -2979,9 +2969,6 @@ struct class_device *tty_register_device(struct tty_driver *driver,
                 return ERR_PTR(-EINVAL);
         }
 
-        devfs_mk_cdev(dev, S_IFCHR | S_IRUSR | S_IWUSR,
-                        "%s%d", driver->devfs_name, index + driver->name_base);
-
         if (driver->type == TTY_DRIVER_TYPE_PTY)
                 pty_line_name(driver, index, name);
         else
@@ -3000,7 +2987,6 @@ struct class_device *tty_register_device(struct tty_driver *driver,
  */
 void tty_unregister_device(struct tty_driver *driver, unsigned index)
 {
-        devfs_remove("%s%d", driver->devfs_name, index + driver->name_base);
         class_device_destroy(tty_class, MKDEV(driver->major, driver->minor_start) + index);
 }
 
@@ -3122,7 +3108,7 @@ int tty_register_driver(struct tty_driver *driver)
         
         list_add(&driver->tty_drivers, &tty_drivers);
         
-        if ( !(driver->flags & TTY_DRIVER_NO_DEVFS) ) {
+        if ( !(driver->flags & TTY_DRIVER_DYNAMIC_DEV) ) {
                 for(i = 0; i < driver->num; i++)
                     tty_register_device(driver, i, NULL);
         }
@@ -3165,7 +3151,7 @@ int tty_unregister_driver(struct tty_driver *driver)
                         driver->termios_locked[i] = NULL;
                         kfree(tp);
                 }
-                if (!(driver->flags & TTY_DRIVER_NO_DEVFS))
+                if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV))
                         tty_unregister_device(driver, i);
         }
         p = driver->ttys;
@@ -3241,14 +3227,12 @@ 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");
-        devfs_mk_cdev(MKDEV(TTYAUX_MAJOR, 0), S_IFCHR|S_IRUGO|S_IWUGO, "tty");
         class_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");
-        devfs_mk_cdev(MKDEV(TTYAUX_MAJOR, 1), S_IFCHR|S_IRUSR|S_IWUSR, "console");
         class_device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 1), NULL, "console");
 
 #ifdef CONFIG_UNIX98_PTYS
@@ -3256,7 +3240,6 @@ static int __init tty_init(void)
         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");
-        devfs_mk_cdev(MKDEV(TTYAUX_MAJOR, 2), S_IFCHR|S_IRUGO|S_IWUGO, "ptmx");
         class_device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
 #endif
 
@@ -3265,7 +3248,6 @@ static int __init tty_init(void)
         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");
-        devfs_mk_cdev(MKDEV(TTY_MAJOR, 0), S_IFCHR|S_IRUSR|S_IWUSR, "vc/0");
         class_device_create(tty_class, NULL, MKDEV(TTY_MAJOR, 0), NULL, "tty0");
 
         vty_init();