diff --git a/drivers/char/amiserial.c b/drivers/char/amiserial.c index 1b21a7adeb58..8228e61bb54d 100644 --- a/drivers/char/amiserial.c +++ b/drivers/char/amiserial.c @@ -1528,6 +1528,7 @@ static void rs_wait_until_sent(struct tty_struct *tty, int timeout) { struct async_struct * info = tty->driver_data; unsigned long orig_jiffies, char_time; + int tty_was_locked = tty_locked(); int lsr; if (serial_paranoia_check(info, tty->name, "rs_wait_until_sent")) @@ -1538,7 +1539,12 @@ static void rs_wait_until_sent(struct tty_struct *tty, int timeout) orig_jiffies = jiffies; - tty_lock_nested(); /* tty_wait_until_sent is called from lots of places */ + /* + * tty_wait_until_sent is called from lots of places, + * with or without the BTM. + */ + if (!tty_was_locked) + tty_lock(); /* * Set the check interval to be 1/5 of the estimated time to * send a single character, and make it at least 1. The check @@ -1579,7 +1585,8 @@ static void rs_wait_until_sent(struct tty_struct *tty, int timeout) break; } __set_current_state(TASK_RUNNING); - tty_unlock(); + if (!tty_was_locked) + tty_unlock(); #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies); #endif diff --git a/drivers/serial/68360serial.c b/drivers/serial/68360serial.c index 16f5f2fab032..edcf1cc089d1 100644 --- a/drivers/serial/68360serial.c +++ b/drivers/serial/68360serial.c @@ -1705,7 +1705,6 @@ static void rs_360_wait_until_sent(struct tty_struct *tty, int timeout) printk("jiff=%lu...", jiffies); #endif - tty_lock_nested(); /* always held already since we come from ->close */ /* We go through the loop at least once because we can't tell * exactly when the last character exits the shifter. There can * be at least two characters waiting to be sent after the buffers @@ -1734,7 +1733,6 @@ static void rs_360_wait_until_sent(struct tty_struct *tty, int timeout) bdp--; } while (bdp->status & BD_SC_READY); current->state = TASK_RUNNING; - tty_unlock(); #ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies); #endif diff --git a/drivers/serial/crisv10.c b/drivers/serial/crisv10.c index 94bfb9f238e1..8e356c5eeae0 100644 --- a/drivers/serial/crisv10.c +++ b/drivers/serial/crisv10.c @@ -3935,7 +3935,6 @@ static void rs_wait_until_sent(struct tty_struct *tty, int timeout) * Check R_DMA_CHx_STATUS bit 0-6=number of available bytes in FIFO * R_DMA_CHx_HWSW bit 31-16=nbr of bytes left in DMA buffer (0=64k) */ - tty_lock_nested(); /* locked already when coming from close */ orig_jiffies = jiffies; while (info->xmit.head != info->xmit.tail || /* More in send queue */ (*info->ostatusadr & 0x007f) || /* more in FIFO */ @@ -3952,7 +3951,6 @@ static void rs_wait_until_sent(struct tty_struct *tty, int timeout) curr_time_usec - info->last_tx_active_usec; } set_current_state(TASK_RUNNING); - tty_unlock(); } /* diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c index 851d7c29132b..cd8511298bcb 100644 --- a/drivers/serial/serial_core.c +++ b/drivers/serial/serial_core.c @@ -60,7 +60,7 @@ static struct lock_class_key port_lock_key; static void uart_change_speed(struct tty_struct *tty, struct uart_state *state, struct ktermios *old_termios); -static void uart_wait_until_sent(struct tty_struct *tty, int timeout); +static void __uart_wait_until_sent(struct uart_port *port, int timeout); static void uart_change_pm(struct uart_state *state, int pm_state); /* @@ -1322,8 +1322,16 @@ static void uart_close(struct tty_struct *tty, struct file *filp) tty->closing = 1; spin_unlock_irqrestore(&port->lock, flags); - if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE) - tty_wait_until_sent(tty, msecs_to_jiffies(port->closing_wait)); + if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE) { + /* + * hack: open-coded tty_wait_until_sent to avoid + * recursive tty_lock + */ + long timeout = msecs_to_jiffies(port->closing_wait); + if (wait_event_interruptible_timeout(tty->write_wait, + !tty_chars_in_buffer(tty), timeout) >= 0) + __uart_wait_until_sent(uport, timeout); + } /* * At this point, we stop accepting input. To do this, we @@ -1339,7 +1347,7 @@ static void uart_close(struct tty_struct *tty, struct file *filp) * has completely drained; this is especially * important if there is a transmit FIFO! */ - uart_wait_until_sent(tty, uport->timeout); + __uart_wait_until_sent(uport, uport->timeout); } uart_shutdown(tty, state); @@ -1373,17 +1381,13 @@ done: mutex_unlock(&port->mutex); } -static void uart_wait_until_sent(struct tty_struct *tty, int timeout) +static void __uart_wait_until_sent(struct uart_port *port, int timeout) { - struct uart_state *state = tty->driver_data; - struct uart_port *port = state->uart_port; unsigned long char_time, expire; if (port->type == PORT_UNKNOWN || port->fifosize == 0) return; - tty_lock_nested(); /* already locked when coming from close */ - /* * Set the check interval to be 1/5 of the estimated time to * send a single character, and make it at least 1. The check @@ -1429,6 +1433,15 @@ static void uart_wait_until_sent(struct tty_struct *tty, int timeout) break; } set_current_state(TASK_RUNNING); /* might not be needed */ +} + +static void uart_wait_until_sent(struct tty_struct *tty, int timeout) +{ + struct uart_state *state = tty->driver_data; + struct uart_port *port = state->uart_port; + + tty_lock(); + __uart_wait_until_sent(port, timeout); tty_unlock(); }