tty: The big operations rework

[linux-2.6-omap-h63xx.git] / drivers / serial / serial_core.c

diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index 6c7a5cf765828fc7007e7e630a5a90b8f6a0c414..1e2b9d826f69a5db2756e8eb477f2249587122e4 100644 (file)
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -532,15 +532,25 @@ uart_write(struct tty_struct *tty, const unsigned char *buf, int count)
 static int uart_write_room(struct tty_struct *tty)
 {
        struct uart_state *state = tty->driver_data;
+       unsigned long flags;
+       int ret;
 
-       return uart_circ_chars_free(&state->info->xmit);
+       spin_lock_irqsave(&state->port->lock, flags);
+       ret = uart_circ_chars_free(&state->info->xmit);
+       spin_unlock_irqrestore(&state->port->lock, flags);
+       return ret;
 }
 
 static int uart_chars_in_buffer(struct tty_struct *tty)
 {
        struct uart_state *state = tty->driver_data;
+       unsigned long flags;
+       int ret;
 
-       return uart_circ_chars_pending(&state->info->xmit);
+       spin_lock_irqsave(&state->port->lock, flags);
+       ret = uart_circ_chars_pending(&state->info->xmit);
+       spin_unlock_irqrestore(&state->port->lock, flags);
+       return ret;
 }
 
 static void uart_flush_buffer(struct tty_struct *tty)
@@ -622,6 +632,11 @@ static int uart_get_info(struct uart_state *state,
        struct serial_struct tmp;
 
        memset(&tmp, 0, sizeof(tmp));
+
+       /* Ensure the state we copy is consistent and no hardware changes
+          occur as we go */
+       mutex_lock(&state->mutex);
+
        tmp.type            = port->type;
        tmp.line            = port->line;
        tmp.port            = port->iobase;
@@ -641,6 +656,8 @@ static int uart_get_info(struct uart_state *state,
        tmp.iomem_reg_shift = port->regshift;
        tmp.iomem_base      = (void *)(unsigned long)port->mapbase;
 
+       mutex_unlock(&state->mutex);
+
        if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
                return -EFAULT;
        return 0;
@@ -918,14 +935,12 @@ static void uart_break_ctl(struct tty_struct *tty, int break_state)
        struct uart_state *state = tty->driver_data;
        struct uart_port *port = state->port;
 
-       lock_kernel();
        mutex_lock(&state->mutex);
 
        if (port->type != PORT_UNKNOWN)
                port->ops->break_ctl(port, break_state);
 
        mutex_unlock(&state->mutex);
-       unlock_kernel();
 }
 
 static int uart_do_autoconfig(struct uart_state *state)
@@ -1074,7 +1089,6 @@ uart_ioctl(struct tty_struct *tty, struct file *filp, unsigned int cmd,
        int ret = -ENOIOCTLCMD;
 
 
-       lock_kernel();
        /*
         * These ioctls don't rely on the hardware to be present.
         */
@@ -1144,10 +1158,9 @@ uart_ioctl(struct tty_struct *tty, struct file *filp, unsigned int cmd,
                break;
        }
        }
- out_up:
+out_up:
        mutex_unlock(&state->mutex);
- out:
-       unlock_kernel();
+out:
        return ret;
 }
 
@@ -1173,7 +1186,6 @@ static void uart_set_termios(struct tty_struct *tty,
                return;
        }
 
-       lock_kernel();
        uart_change_speed(state, old_termios);
 
        /* Handle transition to B0 status */
@@ -1206,7 +1218,6 @@ static void uart_set_termios(struct tty_struct *tty,
                }
                spin_unlock_irqrestore(&state->port->lock, flags);
        }
-       unlock_kernel();
 #if 0
        /*
         * No need to wake up processes in open wait, since they
@@ -1322,11 +1333,11 @@ static void uart_wait_until_sent(struct tty_struct *tty, int timeout)
        struct uart_port *port = state->port;
        unsigned long char_time, expire;
 
-       BUG_ON(!kernel_locked());
-
        if (port->type == PORT_UNKNOWN || port->fifosize == 0)
                return;
 
+       lock_kernel();
+
        /*
         * 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
@@ -1372,6 +1383,7 @@ static void uart_wait_until_sent(struct tty_struct *tty, int timeout)
                        break;
        }
        set_current_state(TASK_RUNNING); /* might not be needed */
+       unlock_kernel();
 }
 
 /*
@@ -2085,7 +2097,9 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *port)
                int ret;
 
                uart_change_pm(state, 0);
+               spin_lock_irq(&port->lock);
                ops->set_mctrl(port, 0);
+               spin_unlock_irq(&port->lock);
                ret = ops->startup(port);
                if (ret == 0) {
                        uart_change_speed(state, NULL);