[PATCH 52/79] serial: replace the state mutex with the tty port mutex

From: Greg Kroah-Hartman
Date: Sat Sep 19 2009 - 17:43:16 EST

From: Alan Cox <alan@xxxxxxxxxxxxxxx>

They cover essentially the same stuff and we can therefore fold it into the
tty_port one.

Signed-off-by: Alan Cox <alan@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
drivers/serial/pmac_zilog.c | 8 +-
drivers/serial/serial_core.c | 227 ++++++++++++++++++++++--------------------
include/linux/serial_core.h | 2 -
3 files changed, 123 insertions(+), 114 deletions(-)

diff --git a/drivers/serial/pmac_zilog.c b/drivers/serial/pmac_zilog.c
index ab4c85b..0dc7868 100644
--- a/drivers/serial/pmac_zilog.c
+++ b/drivers/serial/pmac_zilog.c
@@ -1645,7 +1645,7 @@ static int pmz_suspend(struct macio_dev *mdev, pm_message_t pm_state)
state = pmz_uart_reg.state + uap->port.line;

mutex_lock(&pmz_irq_mutex);
- mutex_lock(&state->mutex);
+ mutex_lock(&state->port.mutex);

spin_lock_irqsave(&uap->port.lock, flags);

@@ -1676,7 +1676,7 @@ static int pmz_suspend(struct macio_dev *mdev, pm_message_t pm_state)
/* Shut the chip down */
pmz_set_scc_power(uap, 0);

- mutex_unlock(&state->mutex);
+ mutex_unlock(&state->port.mutex);
mutex_unlock(&pmz_irq_mutex);

pmz_debug("suspend, switching complete\n");
@@ -1705,7 +1705,7 @@ static int pmz_resume(struct macio_dev *mdev)
state = pmz_uart_reg.state + uap->port.line;

mutex_lock(&pmz_irq_mutex);
- mutex_lock(&state->mutex);
+ mutex_lock(&state->port.mutex);

spin_lock_irqsave(&uap->port.lock, flags);
if (!ZS_IS_OPEN(uap) && !ZS_IS_CONS(uap)) {
@@ -1737,7 +1737,7 @@ static int pmz_resume(struct macio_dev *mdev)
}

bail:
- mutex_unlock(&state->mutex);
+ mutex_unlock(&state->port.mutex);
mutex_unlock(&pmz_irq_mutex);

/* Right now, we deal with delay by blocking here, I'll be
diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index 744dec9..9d42e57 100644
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -633,35 +633,36 @@ static void uart_unthrottle(struct tty_struct *tty)
static int uart_get_info(struct uart_state *state,
struct serial_struct __user *retinfo)
{
- struct uart_port *port = state->uart_port;
+ struct uart_port *uport = state->uart_port;
+ struct tty_port *port = &state->port;
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);
+ mutex_lock(&port->mutex);

- tmp.type = port->type;
- tmp.line = port->line;
- tmp.port = port->iobase;
+ tmp.type = uport->type;
+ tmp.line = uport->line;
+ tmp.port = uport->iobase;
if (HIGH_BITS_OFFSET)
- tmp.port_high = (long) port->iobase >> HIGH_BITS_OFFSET;
- tmp.irq = port->irq;
- tmp.flags = port->flags;
- tmp.xmit_fifo_size = port->fifosize;
- tmp.baud_base = port->uartclk / 16;
- tmp.close_delay = state->port.close_delay / 10;
- tmp.closing_wait = state->port.closing_wait == USF_CLOSING_WAIT_NONE ?
+ tmp.port_high = (long) uport->iobase >> HIGH_BITS_OFFSET;
+ tmp.irq = uport->irq;
+ tmp.flags = uport->flags;
+ tmp.xmit_fifo_size = uport->fifosize;
+ tmp.baud_base = uport->uartclk / 16;
+ tmp.close_delay = port->close_delay / 10;
+ tmp.closing_wait = port->closing_wait == USF_CLOSING_WAIT_NONE ?
ASYNC_CLOSING_WAIT_NONE :
- state->port.closing_wait / 10;
- tmp.custom_divisor = port->custom_divisor;
- tmp.hub6 = port->hub6;
- tmp.io_type = port->iotype;
- tmp.iomem_reg_shift = port->regshift;
- tmp.iomem_base = (void *)(unsigned long)port->mapbase;
+ port->closing_wait / 10;
+ tmp.custom_divisor = uport->custom_divisor;
+ tmp.hub6 = uport->hub6;
+ tmp.io_type = uport->iotype;
+ tmp.iomem_reg_shift = uport->regshift;
+ tmp.iomem_base = (void *)(unsigned long)uport->mapbase;

- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);

if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
return -EFAULT;
@@ -699,7 +700,7 @@ static int uart_set_info(struct uart_state *state,
* module insertion/removal doesn't change anything
* under us.
*/
- mutex_lock(&state->mutex);
+ mutex_lock(&port->mutex);

change_irq = !(uport->flags & UPF_FIXED_PORT)
&& new_serial.irq != uport->irq;
@@ -867,7 +868,7 @@ static int uart_set_info(struct uart_state *state,
} else
retval = uart_startup(state, 1);
exit:
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);
return retval;
}

@@ -902,10 +903,11 @@ static int uart_get_lsr_info(struct uart_state *state,
static int uart_tiocmget(struct tty_struct *tty, struct file *file)
{
struct uart_state *state = tty->driver_data;
+ struct tty_port *port = &state->port;
struct uart_port *uport = state->uart_port;
int result = -EIO;

- mutex_lock(&state->mutex);
+ mutex_lock(&port->mutex);
if ((!file || !tty_hung_up_p(file)) &&
!(tty->flags & (1 << TTY_IO_ERROR))) {
result = uport->mctrl;
@@ -914,7 +916,7 @@ static int uart_tiocmget(struct tty_struct *tty, struct file *file)
result |= uport->ops->get_mctrl(uport);
spin_unlock_irq(&uport->lock);
}
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);

return result;
}
@@ -925,35 +927,38 @@ uart_tiocmset(struct tty_struct *tty, struct file *file,
{
struct uart_state *state = tty->driver_data;
struct uart_port *uport = state->uart_port;
+ struct tty_port *port = &state->port;
int ret = -EIO;

- mutex_lock(&state->mutex);
+ mutex_lock(&port->mutex);
if ((!file || !tty_hung_up_p(file)) &&
!(tty->flags & (1 << TTY_IO_ERROR))) {
uart_update_mctrl(uport, set, clear);
ret = 0;
}
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);
return ret;
}

static int uart_break_ctl(struct tty_struct *tty, int break_state)
{
struct uart_state *state = tty->driver_data;
+ struct tty_port *port = &state->port;
struct uart_port *uport = state->uart_port;

- mutex_lock(&state->mutex);
+ mutex_lock(&port->mutex);

if (uport->type != PORT_UNKNOWN)
uport->ops->break_ctl(uport, break_state);

- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);
return 0;
}

static int uart_do_autoconfig(struct uart_state *state)
{
struct uart_port *uport = state->uart_port;
+ struct tty_port *port = &state->port;
int flags, ret;

if (!capable(CAP_SYS_ADMIN))
@@ -964,7 +969,7 @@ static int uart_do_autoconfig(struct uart_state *state)
* changing, and hence any extra opens of the port while
* we're auto-configuring.
*/
- if (mutex_lock_interruptible(&state->mutex))
+ if (mutex_lock_interruptible(&port->mutex))
return -ERESTARTSYS;

ret = -EBUSY;
@@ -990,7 +995,7 @@ static int uart_do_autoconfig(struct uart_state *state)

ret = uart_startup(state, 1);
}
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);
return ret;
}

@@ -1093,6 +1098,7 @@ uart_ioctl(struct tty_struct *tty, struct file *filp, unsigned int cmd,
unsigned long arg)
{
struct uart_state *state = tty->driver_data;
+ struct tty_port *port = &state->port;
void __user *uarg = (void __user *)arg;
int ret = -ENOIOCTLCMD;

@@ -1143,7 +1149,7 @@ uart_ioctl(struct tty_struct *tty, struct file *filp, unsigned int cmd,
if (ret != -ENOIOCTLCMD)
goto out;

- mutex_lock(&state->mutex);
+ mutex_lock(&port->mutex);

if (tty_hung_up_p(filp)) {
ret = -EIO;
@@ -1167,7 +1173,7 @@ uart_ioctl(struct tty_struct *tty, struct file *filp, unsigned int cmd,
}
}
out_up:
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);
out:
return ret;
}
@@ -1266,7 +1272,7 @@ static void uart_close(struct tty_struct *tty, struct file *filp)

pr_debug("uart_close(%d) called\n", uport->line);

- mutex_lock(&state->mutex);
+ mutex_lock(&port->mutex);

if (tty_hung_up_p(filp))
goto done;
@@ -1340,7 +1346,7 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
wake_up_interruptible(&port->open_wait);

done:
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);
}

static void uart_wait_until_sent(struct tty_struct *tty, int timeout)
@@ -1416,7 +1422,7 @@ static void uart_hangup(struct tty_struct *tty)
BUG_ON(!kernel_locked());
pr_debug("uart_hangup(%d)\n", state->uart_port->line);

- mutex_lock(&state->mutex);
+ mutex_lock(&port->mutex);
if (port->flags & ASYNC_NORMAL_ACTIVE) {
uart_flush_buffer(tty);
uart_shutdown(state);
@@ -1426,7 +1432,7 @@ static void uart_hangup(struct tty_struct *tty)
wake_up_interruptible(&port->open_wait);
wake_up_interruptible(&state->delta_msr_wait);
}
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);
}

/*
@@ -1528,9 +1534,9 @@ uart_block_til_ready(struct file *filp, struct uart_state *state)
if (mctrl & TIOCM_CAR)
break;

- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);
schedule();
- mutex_lock(&state->mutex);
+ mutex_lock(&port->mutex);

if (signal_pending(current))
break;
@@ -1553,15 +1559,17 @@ uart_block_til_ready(struct file *filp, struct uart_state *state)
static struct uart_state *uart_get(struct uart_driver *drv, int line)
{
struct uart_state *state;
+ struct tty_port *port;
int ret = 0;

state = drv->state + line;
- if (mutex_lock_interruptible(&state->mutex)) {
+ port = &state->port;
+ if (mutex_lock_interruptible(&port->mutex)) {
ret = -ERESTARTSYS;
goto err;
}

- state->port.count++;
+ port->count++;
if (!state->uart_port || state->uart_port->flags & UPF_DEAD) {
ret = -ENXIO;
goto err_unlock;
@@ -1569,8 +1577,8 @@ static struct uart_state *uart_get(struct uart_driver *drv, int line)
return state;

err_unlock:
- state->port.count--;
- mutex_unlock(&state->mutex);
+ port->count--;
+ mutex_unlock(&port->mutex);
err:
return ERR_PTR(ret);
}
@@ -1636,7 +1644,7 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
if (tty_hung_up_p(filp)) {
retval = -EAGAIN;
port->count--;
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);
goto fail;
}

@@ -1656,7 +1664,7 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
*/
if (retval == 0)
retval = uart_block_til_ready(filp, state);
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);

/*
* If this is the first open to succeed, adjust things to suit.
@@ -1667,7 +1675,7 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
uart_update_termios(state);
}

- fail:
+fail:
return retval;
}

@@ -1689,57 +1697,58 @@ static const char *uart_type(struct uart_port *port)
static void uart_line_info(struct seq_file *m, struct uart_driver *drv, int i)
{
struct uart_state *state = drv->state + i;
+ struct tty_port *port = &state->port;
int pm_state;
- struct uart_port *port = state->uart_port;
+ struct uart_port *uport = state->uart_port;
char stat_buf[32];
unsigned int status;
int mmio;

- if (!port)
+ if (!uport)
return;

- mmio = port->iotype >= UPIO_MEM;
+ mmio = uport->iotype >= UPIO_MEM;
seq_printf(m, "%d: uart:%s %s%08llX irq:%d",
- port->line, uart_type(port),
+ uport->line, uart_type(uport),
mmio ? "mmio:0x" : "port:",
- mmio ? (unsigned long long)port->mapbase
- : (unsigned long long) port->iobase,
- port->irq);
+ mmio ? (unsigned long long)uport->mapbase
+ : (unsigned long long)uport->iobase,
+ uport->irq);

- if (port->type == PORT_UNKNOWN) {
+ if (uport->type == PORT_UNKNOWN) {
seq_putc(m, '\n');
return;
}

if (capable(CAP_SYS_ADMIN)) {
- mutex_lock(&state->mutex);
+ mutex_lock(&port->mutex);
pm_state = state->pm_state;
if (pm_state)
uart_change_pm(state, 0);
- spin_lock_irq(&port->lock);
- status = port->ops->get_mctrl(port);
- spin_unlock_irq(&port->lock);
+ spin_lock_irq(&uport->lock);
+ status = uport->ops->get_mctrl(uport);
+ spin_unlock_irq(&uport->lock);
if (pm_state)
uart_change_pm(state, pm_state);
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);

seq_printf(m, " tx:%d rx:%d",
- port->icount.tx, port->icount.rx);
- if (port->icount.frame)
+ uport->icount.tx, uport->icount.rx);
+ if (uport->icount.frame)
seq_printf(m, " fe:%d",
- port->icount.frame);
- if (port->icount.parity)
+ uport->icount.frame);
+ if (uport->icount.parity)
seq_printf(m, " pe:%d",
- port->icount.parity);
- if (port->icount.brk)
+ uport->icount.parity);
+ if (uport->icount.brk)
seq_printf(m, " brk:%d",
- port->icount.brk);
- if (port->icount.overrun)
+ uport->icount.brk);
+ if (uport->icount.overrun)
seq_printf(m, " oe:%d",
- port->icount.overrun);
+ uport->icount.overrun);

#define INFOBIT(bit, str) \
- if (port->mctrl & (bit)) \
+ if (uport->mctrl & (bit)) \
strncat(stat_buf, (str), sizeof(stat_buf) - \
strlen(stat_buf) - 2)
#define STATBIT(bit, str) \
@@ -1991,11 +2000,11 @@ int uart_suspend_port(struct uart_driver *drv, struct uart_port *uport)
struct device *tty_dev;
struct uart_match match = {uport, drv};

- mutex_lock(&state->mutex);
+ mutex_lock(&port->mutex);

if (!console_suspend_enabled && uart_console(uport)) {
/* we're going to avoid suspending serial console */
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);
return 0;
}

@@ -2003,7 +2012,7 @@ int uart_suspend_port(struct uart_driver *drv, struct uart_port *uport)
if (device_may_wakeup(tty_dev)) {
enable_irq_wake(uport->irq);
put_device(tty_dev);
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);
return 0;
}
uport->suspended = 1;
@@ -2045,7 +2054,7 @@ int uart_suspend_port(struct uart_driver *drv, struct uart_port *uport)

uart_change_pm(state, 3);

- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);

return 0;
}
@@ -2057,18 +2066,18 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *uport)
struct device *tty_dev;
struct uart_match match = {uport, drv};

- mutex_lock(&state->mutex);
+ mutex_lock(&port->mutex);

if (!console_suspend_enabled && uart_console(uport)) {
/* no need to resume serial console, it wasn't suspended */
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);
return 0;
}

tty_dev = device_find_child(uport->dev, &match, serial_match_port);
if (!uport->suspended && device_may_wakeup(tty_dev)) {
disable_irq_wake(uport->irq);
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);
return 0;
}
uport->suspended = 0;
@@ -2124,7 +2133,7 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *uport)
clear_bit(ASYNCB_SUSPENDED, &port->flags);
}

- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);

return 0;
}
@@ -2364,12 +2373,11 @@ int uart_register_driver(struct uart_driver *drv)
*/
for (i = 0; i < drv->nr; i++) {
struct uart_state *state = drv->state + i;
+ struct tty_port *port = &state->port;

- mutex_init(&state->mutex);
-
- tty_port_init(&state->port);
- state->port.close_delay = 500; /* .5 seconds */
- state->port.closing_wait = 30000; /* 30 seconds */
+ tty_port_init(port);
+ port->close_delay = 500; /* .5 seconds */
+ port->closing_wait = 30000; /* 30 seconds */
init_waitqueue_head(&state->delta_msr_wait);
tasklet_init(&state->tlet, uart_tasklet_action,
(unsigned long)state);
@@ -2419,62 +2427,64 @@ struct tty_driver *uart_console_device(struct console *co, int *index)
* level uart drivers to expand uart_port, rather than having yet
* more levels of structures.
*/
-int uart_add_one_port(struct uart_driver *drv, struct uart_port *port)
+int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport)
{
struct uart_state *state;
+ struct tty_port *port;
int ret = 0;
struct device *tty_dev;

BUG_ON(in_interrupt());

- if (port->line >= drv->nr)
+ if (uport->line >= drv->nr)
return -EINVAL;

- state = drv->state + port->line;
+ state = drv->state + uport->line;
+ port = &state->port;

mutex_lock(&port_mutex);
- mutex_lock(&state->mutex);
+ mutex_lock(&port->mutex);
if (state->uart_port) {
ret = -EINVAL;
goto out;
}

- state->uart_port = port;
+ state->uart_port = uport;
state->pm_state = -1;

- port->cons = drv->cons;
- port->state = state;
+ uport->cons = drv->cons;
+ uport->state = state;

/*
* If this port is a console, then the spinlock is already
* initialised.
*/
- if (!(uart_console(port) && (port->cons->flags & CON_ENABLED))) {
- spin_lock_init(&port->lock);
- lockdep_set_class(&port->lock, &port_lock_key);
+ if (!(uart_console(uport) && (uport->cons->flags & CON_ENABLED))) {
+ spin_lock_init(&uport->lock);
+ lockdep_set_class(&uport->lock, &port_lock_key);
}

- uart_configure_port(drv, state, port);
+ uart_configure_port(drv, state, uport);

/*
* Register the port whether it's detected or not. This allows
* setserial to be used to alter this ports parameters.
*/
- tty_dev = tty_register_device(drv->tty_driver, port->line, port->dev);
+ tty_dev = tty_register_device(drv->tty_driver, uport->line, uport->dev);
if (likely(!IS_ERR(tty_dev))) {
device_init_wakeup(tty_dev, 1);
device_set_wakeup_enable(tty_dev, 0);
} else
printk(KERN_ERR "Cannot register tty device on line %d\n",
- port->line);
+ uport->line);

/*
* Ensure UPF_DEAD is not set.
*/
- port->flags &= ~UPF_DEAD;
+ uport->flags &= ~UPF_DEAD;

out:
- mutex_unlock(&state->mutex);
+ mutex_unlock(&port->mutex);
mutex_unlock(&port_mutex);

return ret;
@@ -2489,15 +2499,16 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *port)
* core driver. No further calls will be made to the low-level code
* for this port.
*/
-int uart_remove_one_port(struct uart_driver *drv, struct uart_port *port)
+int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport)
{
- struct uart_state *state = drv->state + port->line;
+ struct uart_state *state = drv->state + uport->line;
+ struct tty_port *port = &state->port;

BUG_ON(in_interrupt());

- if (state->uart_port != port)
+ if (state->uart_port != uport)
printk(KERN_ALERT "Removing wrong port: %p != %p\n",
- state->uart_port, port);
+ state->uart_port, uport);

mutex_lock(&port_mutex);

@@ -2505,28 +2516,28 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *port)
* Mark the port "dead" - this prevents any opens from
* succeeding while we shut down the port.
*/
- mutex_lock(&state->mutex);
- port->flags |= UPF_DEAD;
- mutex_unlock(&state->mutex);
+ mutex_lock(&port->mutex);
+ uport->flags |= UPF_DEAD;
+ mutex_unlock(&port->mutex);

/*
* Remove the devices from the tty layer
*/
- tty_unregister_device(drv->tty_driver, port->line);
+ tty_unregister_device(drv->tty_driver, uport->line);

- if (state->port.tty)
- tty_vhangup(state->port.tty);
+ if (port->tty)
+ tty_vhangup(port->tty);

/*
* Free the port IO and memory resources, if any.
*/
- if (port->type != PORT_UNKNOWN)
- port->ops->release_port(port);
+ if (uport->type != PORT_UNKNOWN)
+ uport->ops->release_port(uport);

/*
* Indicate that there isn't a port here anymore.
*/
- port->type = PORT_UNKNOWN;
+ uport->type = PORT_UNKNOWN;

/*
* Kill the tasklet, and free resources.
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index f98dc78..27767ea 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -351,8 +351,6 @@ struct uart_state {
struct tasklet_struct tlet;
wait_queue_head_t delta_msr_wait;
struct uart_port *uart_port;
-
- struct mutex mutex;
};

#define UART_XMIT_SIZE PAGE_SIZE
--
1.6.4.2

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