tty: BKL pushdown

[safe/jmp/linux-2.6] / drivers / char / n_hdlc.c

diff --git a/drivers/char/n_hdlc.c b/drivers/char/n_hdlc.c
index 06803ed..a07c0af 100644 (file)
--- a/drivers/char/n_hdlc.c
+++ b/drivers/char/n_hdlc.c
@@ -578,26 +578,36 @@ static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
                return -EFAULT;
        }
 
+       lock_kernel();
+
        for (;;) {
-               if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
+               if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) {
+                       unlock_kernel();
                        return -EIO;
+               }
 
                n_hdlc = tty2n_hdlc (tty);
                if (!n_hdlc || n_hdlc->magic != HDLC_MAGIC ||
-                        tty != n_hdlc->tty)
+                        tty != n_hdlc->tty) {
+                       unlock_kernel();
                        return 0;
+               }
 
                rbuf = n_hdlc_buf_get(&n_hdlc->rx_buf_list);
                if (rbuf)
                        break;
                        
                /* no data */
-               if (file->f_flags & O_NONBLOCK)
+               if (file->f_flags & O_NONBLOCK) {
+                       unlock_kernel();
                        return -EAGAIN;
+               }
                        
                interruptible_sleep_on (&tty->read_wait);
-               if (signal_pending(current))
+               if (signal_pending(current)) {
+                       unlock_kernel();
                        return -EINTR;
+               }
        }
                
        if (rbuf->count > nr)
@@ -618,7 +628,7 @@ static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
                kfree(rbuf);
        else    
                n_hdlc_buf_put(&n_hdlc->rx_free_buf_list,rbuf);
-       
+       unlock_kernel();
        return ret;
        
 }      /* end of n_hdlc_tty_read() */
@@ -661,6 +671,8 @@ static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file,
                count = maxframe;
        }
        
+       lock_kernel();
+
        add_wait_queue(&tty->write_wait, &wait);
        set_current_state(TASK_INTERRUPTIBLE);
        
@@ -695,7 +707,7 @@ static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file,
                n_hdlc_buf_put(&n_hdlc->tx_buf_list,tbuf);
                n_hdlc_send_frames(n_hdlc,tty);
        }
-
+       unlock_kernel();
        return error;
        
 }      /* end of n_hdlc_tty_write() */