1 files changed, 45 insertions, 45 deletions

diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c
index 47d32281032c..52fc0c9a6364 100644
--- a/drivers/tty/n_hdlc.c
+++ b/drivers/tty/n_hdlc.c
@@ -581,8 +581,9 @@ static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
                            __u8 __user *buf, size_t nr)
 {
         struct n_hdlc *n_hdlc = tty2n_hdlc(tty);
-        int ret;
+        int ret = 0;
         struct n_hdlc_buf *rbuf;
+        DECLARE_WAITQUEUE(wait, current);
 
         if (debuglevel >= DEBUG_LEVEL_INFO)     
                 printk("%s(%d)n_hdlc_tty_read() called\n",__FILE__,__LINE__);
@@ -598,57 +599,55 @@ static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
                 return -EFAULT;
         }
 
-        tty_lock();
+        add_wait_queue(&tty->read_wait, &wait);
 
         for (;;) {
                 if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) {
-                        tty_unlock();
-                        return -EIO;
+                        ret = -EIO;
+                        break;
                 }
+                if (tty_hung_up_p(file))
+                        break;
 
-                n_hdlc = tty2n_hdlc (tty);
-                if (!n_hdlc || n_hdlc->magic != HDLC_MAGIC ||
-                         tty != n_hdlc->tty) {
-                        tty_unlock();
-                        return 0;
-                }
+                set_current_state(TASK_INTERRUPTIBLE);
 
                 rbuf = n_hdlc_buf_get(&n_hdlc->rx_buf_list);
-                if (rbuf)
+                if (rbuf) {
+                        if (rbuf->count > nr) {
+                                /* too large for caller's buffer */
+                                ret = -EOVERFLOW;
+                        } else {
+                                if (copy_to_user(buf, rbuf->buf, rbuf->count))
+                                        ret = -EFAULT;
+                                else
+                                        ret = rbuf->count;
+                        }
+
+                        if (n_hdlc->rx_free_buf_list.count >
+                            DEFAULT_RX_BUF_COUNT)
+                                kfree(rbuf);
+                        else
+                                n_hdlc_buf_put(&n_hdlc->rx_free_buf_list, rbuf);
                         break;
+                }
                         
                 /* no data */
                 if (file->f_flags & O_NONBLOCK) {
-                        tty_unlock();
-                        return -EAGAIN;
+                        ret = -EAGAIN;
+                        break;
                 }
-                        
-                interruptible_sleep_on (&tty->read_wait);
+
+                schedule();
+
                 if (signal_pending(current)) {
-                        tty_unlock();
-                        return -EINTR;
+                        ret = -EINTR;
+                        break;
                 }
         }
-                
-        if (rbuf->count > nr)
-                /* frame too large for caller's buffer (discard frame) */
-                ret = -EOVERFLOW;
-        else {
-                /* Copy the data to the caller's buffer */
-                if (copy_to_user(buf, rbuf->buf, rbuf->count))
-                        ret = -EFAULT;
-                else
-                        ret = rbuf->count;
-        }
-        
-        /* return HDLC buffer to free list unless the free list */
-        /* count has exceeded the default value, in which case the */
-        /* buffer is freed back to the OS to conserve memory */
-        if (n_hdlc->rx_free_buf_list.count > DEFAULT_RX_BUF_COUNT)
-                kfree(rbuf);
-        else    
-                n_hdlc_buf_put(&n_hdlc->rx_free_buf_list,rbuf);
-        tty_unlock();
+
+        remove_wait_queue(&tty->read_wait, &wait);
+        __set_current_state(TASK_RUNNING);
+
         return ret;
         
 }       /* end of n_hdlc_tty_read() */
@@ -691,14 +690,15 @@ static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file,
                 count = maxframe;
         }
         
-        tty_lock();
-
         add_wait_queue(&tty->write_wait, &wait);
-        set_current_state(TASK_INTERRUPTIBLE);
+
+        for (;;) {
+                set_current_state(TASK_INTERRUPTIBLE);
         
-        /* Allocate transmit buffer */
-        /* sleep until transmit buffer available */             
-        while (!(tbuf = n_hdlc_buf_get(&n_hdlc->tx_free_buf_list))) {
+                tbuf = n_hdlc_buf_get(&n_hdlc->tx_free_buf_list);
+                if (tbuf)
+                        break;
+
                 if (file->f_flags & O_NONBLOCK) {
                         error = -EAGAIN;
                         break;
@@ -719,7 +719,7 @@ static ssize_t n_hdlc_tty_write(struct tty_struct *tty, struct file *file,
                 }
         }
 
-        set_current_state(TASK_RUNNING);
+        __set_current_state(TASK_RUNNING);
         remove_wait_queue(&tty->write_wait, &wait);
 
         if (!error) {           
@@ -731,7 +731,7 @@ 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);
         }
-        tty_unlock();
+
         return error;
         
 }       /* end of n_hdlc_tty_write() */