Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...

[firefly-linux-kernel-4.4.55.git] / drivers / tty / pty.c

diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index 79ff3a5e925d6fdc252c6aa6d2f066e959e4637f..c24b4db243b97fb97721730c6b5a7f57c2966ace 100644 (file)
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -38,16 +38,18 @@ static void pty_close(struct tty_struct *tty, struct file *filp)
        if (tty->driver->subtype == PTY_TYPE_MASTER)
                WARN_ON(tty->count > 1);
        else {
+               if (test_bit(TTY_IO_ERROR, &tty->flags))
+                       return;
                if (tty->count > 2)
                        return;
        }
+       set_bit(TTY_IO_ERROR, &tty->flags);
        wake_up_interruptible(&tty->read_wait);
        wake_up_interruptible(&tty->write_wait);
        tty->packet = 0;
        /* Review - krefs on tty_link ?? */
        if (!tty->link)
                return;
-       tty->link->packet = 0;
        set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
        wake_up_interruptible(&tty->link->read_wait);
        wake_up_interruptible(&tty->link->write_wait);
@@ -55,9 +57,10 @@ static void pty_close(struct tty_struct *tty, struct file *filp)
                set_bit(TTY_OTHER_CLOSED, &tty->flags);
 #ifdef CONFIG_UNIX98_PTYS
                if (tty->driver == ptm_driver) {
-                       mutex_lock(&devpts_mutex);
-                       devpts_pty_kill(tty->link->driver_data);
-                       mutex_unlock(&devpts_mutex);
+                       mutex_lock(&devpts_mutex);
+                       if (tty->link->driver_data)
+                               devpts_pty_kill(tty->link->driver_data);
+                       mutex_unlock(&devpts_mutex);
                }
 #endif
                tty_unlock(tty);
@@ -120,10 +123,10 @@ static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
 
        if (c > 0) {
                /* Stuff the data into the input queue of the other end */
-               c = tty_insert_flip_string(to, buf, c);
+               c = tty_insert_flip_string(to->port, buf, c);
                /* And shovel */
                if (c) {
-                       tty_flip_buffer_push(to);
+                       tty_flip_buffer_push(to->port);
                        tty_wakeup(tty);
                }
        }
@@ -246,14 +249,17 @@ static int pty_open(struct tty_struct *tty, struct file *filp)
        if (!tty || !tty->link)
                goto out;
 
+       set_bit(TTY_IO_ERROR, &tty->flags);
+
        retval = -EIO;
        if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
                goto out;
        if (test_bit(TTY_PTY_LOCK, &tty->link->flags))
                goto out;
-       if (tty->link->count != 1)
+       if (tty->driver->subtype == PTY_TYPE_SLAVE && tty->link->count != 1)
                goto out;
 
+       clear_bit(TTY_IO_ERROR, &tty->flags);
        clear_bit(TTY_OTHER_CLOSED, &tty->link->flags);
        set_bit(TTY_THROTTLED, &tty->flags);
        retval = 0;
@@ -663,7 +669,7 @@ static const struct tty_operations pty_unix98_ops = {
  *     Allocate a unix98 pty master device from the ptmx driver.
  *
  *     Locking: tty_mutex protects the init_dev work. tty->count should
- *             protect the rest.
+ *             protect the rest.
  *             allocated_ptys_lock handles the list of free pty numbers
  */
 
@@ -704,6 +710,7 @@ static int ptmx_open(struct inode *inode, struct file *filp)
        mutex_unlock(&tty_mutex);
 
        set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
+       tty->driver_data = inode;
 
        tty_add_file(tty, filp);
 
@@ -714,14 +721,13 @@ static int ptmx_open(struct inode *inode, struct file *filp)
                retval = PTR_ERR(slave_inode);
                goto err_release;
        }
+       tty->link->driver_data = slave_inode;
 
        retval = ptm_driver->ops->open(tty, filp);
        if (retval)
                goto err_release;
 
        tty_unlock(tty);
-       tty->driver_data = inode;
-       tty->link->driver_data = slave_inode;
        return 0;
 err_release:
        tty_unlock(tty);
@@ -797,7 +803,7 @@ static void __init unix98_pty_init(void)
        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");
+               panic("Couldn't register /dev/ptmx driver");
        device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
 }