free_page((unsigned long) buf);
}
-static inline void put_tty_queue_nolock(unsigned char c, struct tty_struct *tty)
+/**
+ * n_tty_set__room - receive space
+ * @tty: terminal
+ *
+ * Called by the driver to find out how much data it is
+ * permitted to feed to the line discipline without any being lost
+ * and thus to manage flow control. Not serialized. Answers for the
+ * "instant".
+ */
+
+static void n_tty_set_room(struct tty_struct *tty)
+{
+ int left = N_TTY_BUF_SIZE - tty->read_cnt - 1;
+
+ /*
+ * If we are doing input canonicalization, and there are no
+ * pending newlines, let characters through without limit, so
+ * that erase characters will be handled. Other excess
+ * characters will be beeped.
+ */
+ if (left <= 0)
+ left = tty->icanon && !tty->canon_data;
+ tty->receive_room = left;
+}
+
+static void put_tty_queue_nolock(unsigned char c, struct tty_struct *tty)
{
if (tty->read_cnt < N_TTY_BUF_SIZE) {
tty->read_buf[tty->read_head] = c;
}
}
-static inline void put_tty_queue(unsigned char c, struct tty_struct *tty)
+static void put_tty_queue(unsigned char c, struct tty_struct *tty)
{
unsigned long flags;
/*
* We test the TTY_THROTTLED bit first so that it always
* indicates the current state. The decision about whether
* it is worth allowing more input has been taken by the caller.
- * Can sleep, may be called under the atomic_read semaphore but
+ * Can sleep, may be called under the atomic_read_lock mutex but
* this is not guaranteed.
*/
spin_unlock_irqrestore(&tty->read_lock, flags);
tty->canon_head = tty->canon_data = tty->erasing = 0;
memset(&tty->read_flags, 0, sizeof tty->read_flags);
+ n_tty_set_room(tty);
check_unthrottle(tty);
}
put_tty_queue(c, tty);
}
-/**
- * n_tty_receive_room - receive space
- * @tty: terminal
- *
- * Called by the driver to find out how much data it is
- * permitted to feed to the line discipline without any being lost
- * and thus to manage flow control. Not serialized. Answers for the
- * "instant".
- */
-
-static int n_tty_receive_room(struct tty_struct *tty)
-{
- int left = N_TTY_BUF_SIZE - tty->read_cnt - 1;
-
- /*
- * If we are doing input canonicalization, and there are no
- * pending newlines, let characters through without limit, so
- * that erase characters will be handled. Other excess
- * characters will be beeped.
- */
- if (left <= 0)
- left = tty->icanon && !tty->canon_data;
- return left;
-}
/**
* n_tty_write_wakeup - asynchronous I/O notifier
tty->driver->flush_chars(tty);
}
+ n_tty_set_room(tty);
+
if (!tty->icanon && (tty->read_cnt >= tty->minimum_to_wake)) {
kill_fasync(&tty->fasync, SIGIO, POLL_IN);
if (waitqueue_active(&tty->read_wait))
* mode. We don't want to throttle the driver if we're in
* canonical mode and don't have a newline yet!
*/
- if (n_tty_receive_room(tty) < TTY_THRESHOLD_THROTTLE) {
+ if (tty->receive_room < TTY_THRESHOLD_THROTTLE) {
/* check TTY_THROTTLED first so it indicates our state */
if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) &&
tty->driver->throttle)
if (test_bit(TTY_HW_COOK_IN, &tty->flags)) {
tty->raw = 1;
tty->real_raw = 1;
+ n_tty_set_room(tty);
return;
}
if (I_ISTRIP(tty) || I_IUCLC(tty) || I_IGNCR(tty) ||
else
tty->real_raw = 0;
}
+ n_tty_set_room(tty);
}
/**
* buffer, and once to drain the space from the (physical) beginning of
* the buffer to head pointer.
*
- * Called under the tty->atomic_read sem and with TTY_DONT_FLIP set
+ * Called under the tty->atomic_read_lock sem and with TTY_DONT_FLIP set
*
*/
-static inline int copy_from_read_buf(struct tty_struct *tty,
+static int copy_from_read_buf(struct tty_struct *tty,
unsigned char __user **b,
size_t *nr)
* Internal serialization of reads.
*/
if (file->f_flags & O_NONBLOCK) {
- if (down_trylock(&tty->atomic_read))
+ if (!mutex_trylock(&tty->atomic_read_lock))
return -EAGAIN;
}
else {
- if (down_interruptible(&tty->atomic_read))
+ if (mutex_lock_interruptible(&tty->atomic_read_lock))
return -ERESTARTSYS;
}
retval = -ERESTARTSYS;
break;
}
+ n_tty_set_room(tty);
clear_bit(TTY_DONT_FLIP, &tty->flags);
timeout = schedule_timeout(timeout);
set_bit(TTY_DONT_FLIP, &tty->flags);
timeout = time;
}
clear_bit(TTY_DONT_FLIP, &tty->flags);
- up(&tty->atomic_read);
+ mutex_unlock(&tty->atomic_read_lock);
remove_wait_queue(&tty->read_wait, &wait);
if (!waitqueue_active(&tty->read_wait))
} else if (test_and_clear_bit(TTY_PUSH, &tty->flags))
goto do_it_again;
+ n_tty_set_room(tty);
+
return retval;
}
normal_poll, /* poll */
NULL, /* hangup */
n_tty_receive_buf, /* receive_buf */
- n_tty_receive_room, /* receive_room */
n_tty_write_wakeup /* write_wakeup */
};