[PATCH 15/20] serial: use tty_port

Alan Cox
2008-05-19T15:08:21Z

Switch the serial_core based drivers to use the new tty_port structure. We
can't quite use all of it yet because of the dynamically allocated extras
in the serial_core layer.
---

drivers/serial/8250.c | 2 +
drivers/serial/jsm/jsm_neo.c | 2 +
drivers/serial/jsm/jsm_tty.c | 8 ++--
drivers/serial/serial_core.c | 80 ++++++++++++++++++++++--------------------
include/linux/serial_core.h | 26 ++++++--------
5 files changed, 60 insertions(+), 58 deletions(-)

diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index a1ca9b7..56ca93a 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -1290,7 +1290,7 @@ static void serial8250_enable_ms(struct uart_port *port)
static void
receive_chars(struct uart_8250_port *up, unsigned int *status)
{
- struct tty_struct *tty = up->port.info->tty;
+ struct tty_struct *tty = up->port.info->port.tty;
unsigned char ch, lsr = *status;
int max_count = 256;
char flag;
diff --git a/drivers/serial/jsm/jsm_neo.c b/drivers/serial/jsm/jsm_neo.c
index b2d6f5b..b7584ca 100644
--- a/drivers/serial/jsm/jsm_neo.c
+++ b/drivers/serial/jsm/jsm_neo.c
@@ -998,7 +998,7 @@ static void neo_param(struct jsm_channel *ch)
{ 50, B50 },
};

- cflag = C_BAUD(ch->uart_port.info->tty);
+ cflag = C_BAUD(ch->uart_port.info->port.tty);
baud = 9600;
for (i = 0; i < ARRAY_SIZE(baud_rates); i++) {
if (baud_rates[i].cflag == cflag) {
diff --git a/drivers/serial/jsm/jsm_tty.c b/drivers/serial/jsm/jsm_tty.c
index 94ec663..a697914 100644
--- a/drivers/serial/jsm/jsm_tty.c
+++ b/drivers/serial/jsm/jsm_tty.c
@@ -145,7 +145,7 @@ static void jsm_tty_send_xchar(struct uart_port *port, char ch)
struct ktermios *termios;

spin_lock_irqsave(&port->lock, lock_flags);
- termios = port->info->tty->termios;
+ termios = port->info->port.tty->termios;
if (ch == termios->c_cc[VSTART])
channel->ch_bd->bd_ops->send_start_character(channel);

@@ -239,7 +239,7 @@ static int jsm_tty_open(struct uart_port *port)
channel->ch_cached_lsr = 0;
channel->ch_stops_sent = 0;

- termios = port->info->tty->termios;
+ termios = port->info->port.tty->termios;
channel->ch_c_cflag = termios->c_cflag;
channel->ch_c_iflag = termios->c_iflag;
channel->ch_c_oflag = termios->c_oflag;
@@ -272,7 +272,7 @@ static void jsm_tty_close(struct uart_port *port)
jsm_printk(CLOSE, INFO, &channel->ch_bd->pci_dev, "start\n");

bd = channel->ch_bd;
- ts = channel->uart_port.info->tty->termios;
+ ts = channel->uart_port.info->port.tty->termios;

channel->ch_flags &= ~(CH_STOPI);

@@ -515,7 +515,7 @@ void jsm_input(struct jsm_channel *ch)
if (!ch)
return;

- tp = ch->uart_port.info->tty;
+ tp = ch->uart_port.info->port.tty;

bd = ch->ch_bd;
if(!bd)
diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index eab0327..1c4fe79 100644
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -50,7 +50,7 @@ static struct lock_class_key port_lock_key;

#define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8)

-#define uart_users(state) ((state)->count + ((state)->info ? (state)->info->blocked_open : 0))
+#define uart_users(state) ((state)->count + ((state)->info ? (state)->info->port.blocked_open : 0))

#ifdef CONFIG_SERIAL_CORE_CONSOLE
#define uart_console(port) ((port)->cons && (port)->cons->index == (port)->line)
@@ -113,7 +113,7 @@ static void uart_start(struct tty_struct *tty)
static void uart_tasklet_action(unsigned long data)
{
struct uart_state *state = (struct uart_state *)data;
- tty_wakeup(state->info->tty);
+ tty_wakeup(state->info->port.tty);
}

static inline void
@@ -135,7 +135,7 @@ uart_update_mctrl(struct uart_port *port, unsigned int set, unsigned int clear)

/*
* Startup the port. This will be called once per open. All calls
- * will be serialised by the per-port semaphore.
+ * will be serialised by the per-port mutex.
*/
static int uart_startup(struct uart_state *state, int init_hw)
{
@@ -152,7 +152,7 @@ static int uart_startup(struct uart_state *state, int init_hw)
* once we have successfully opened the port. Also set
* up the tty->alt_speed kludge
*/
- set_bit(TTY_IO_ERROR, &info->tty->flags);
+ set_bit(TTY_IO_ERROR, &info->port.tty->flags);

if (port->type == PORT_UNKNOWN)
return 0;
@@ -162,6 +162,7 @@ static int uart_startup(struct uart_state *state, int init_hw)
* buffer.
*/
if (!info->xmit.buf) {
+ /* This is protected by the per port mutex */
page = get_zeroed_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
@@ -182,20 +183,20 @@ static int uart_startup(struct uart_state *state, int init_hw)
* Setup the RTS and DTR signals once the
* port is open and ready to respond.
*/
- if (info->tty->termios->c_cflag & CBAUD)
+ if (info->port.tty->termios->c_cflag & CBAUD)
uart_set_mctrl(port, TIOCM_RTS | TIOCM_DTR);
}

if (info->flags & UIF_CTS_FLOW) {
spin_lock_irq(&port->lock);
if (!(port->ops->get_mctrl(port) & TIOCM_CTS))
- info->tty->hw_stopped = 1;
+ info->port.tty->hw_stopped = 1;
spin_unlock_irq(&port->lock);
}

info->flags |= UIF_INITIALIZED;

- clear_bit(TTY_IO_ERROR, &info->tty->flags);
+ clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
}

if (retval && capable(CAP_SYS_ADMIN))
@@ -217,8 +218,8 @@ static void uart_shutdown(struct uart_state *state)
/*
* Set the TTY IO error marker
*/
- if (info->tty)
- set_bit(TTY_IO_ERROR, &info->tty->flags);
+ if (info->port.tty)
+ set_bit(TTY_IO_ERROR, &info->port.tty->flags);

if (info->flags & UIF_INITIALIZED) {
info->flags &= ~UIF_INITIALIZED;
@@ -226,7 +227,7 @@ static void uart_shutdown(struct uart_state *state)
/*
* Turn off DTR and RTS early.
*/
- if (!info->tty || (info->tty->termios->c_cflag & HUPCL))
+ if (!info->port.tty || (info->port.tty->termios->c_cflag & HUPCL))
uart_clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);

/*
@@ -426,7 +427,7 @@ EXPORT_SYMBOL(uart_get_divisor);
static void
uart_change_speed(struct uart_state *state, struct ktermios *old_termios)
{
- struct tty_struct *tty = state->info->tty;
+ struct tty_struct *tty = state->info->port.tty;
struct uart_port *port = state->port;
struct ktermios *termios;

@@ -834,8 +835,8 @@ static int uart_set_info(struct uart_state *state,
state->closing_wait = closing_wait;
if (new_serial.xmit_fifo_size)
port->fifosize = new_serial.xmit_fifo_size;
- if (state->info->tty)
- state->info->tty->low_latency =
+ if (state->info->port.tty)
+ state->info->port.tty->low_latency =
(port->flags & UPF_LOW_LATENCY) ? 1 : 0;

check_and_exit:
@@ -855,7 +856,7 @@ static int uart_set_info(struct uart_state *state,
printk(KERN_NOTICE
"%s sets custom speed on %s. This "
"is deprecated.\n", current->comm,
- tty_name(state->info->tty, buf));
+ tty_name(state->info->port.tty, buf));
}
uart_change_speed(state, NULL);
}
@@ -887,7 +888,7 @@ static int uart_get_lsr_info(struct uart_state *state,
*/
if (port->x_char ||
((uart_circ_chars_pending(&state->info->xmit) > 0) &&
- !state->info->tty->stopped && !state->info->tty->hw_stopped))
+ !state->info->port.tty->stopped && !state->info->port.tty->hw_stopped))
result &= ~TIOCSER_TEMT;

return put_user(result, value);
@@ -1228,7 +1229,7 @@ static void uart_set_termios(struct tty_struct *tty,
*/
if (!(old_termios->c_cflag & CLOCAL) &&
(tty->termios->c_cflag & CLOCAL))
- wake_up_interruptible(&state->info->open_wait);
+ wake_up_interruptible(&state->info->port.open_wait);
#endif
}

@@ -1309,9 +1310,9 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
tty_ldisc_flush(tty);

tty->closing = 0;
- state->info->tty = NULL;
+ state->info->port.tty = NULL;

- if (state->info->blocked_open) {
+ if (state->info->port.blocked_open) {
if (state->close_delay)
msleep_interruptible(state->close_delay);
} else if (!uart_console(port)) {
@@ -1322,7 +1323,7 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
* Wake up anyone trying to open this port.
*/
state->info->flags &= ~UIF_NORMAL_ACTIVE;
- wake_up_interruptible(&state->info->open_wait);
+ wake_up_interruptible(&state->info->port.open_wait);

done:
mutex_unlock(&state->mutex);
@@ -1406,8 +1407,8 @@ static void uart_hangup(struct tty_struct *tty)
uart_shutdown(state);
state->count = 0;
state->info->flags &= ~UIF_NORMAL_ACTIVE;
- state->info->tty = NULL;
- wake_up_interruptible(&state->info->open_wait);
+ state->info->port.tty = NULL;
+ wake_up_interruptible(&state->info->port.open_wait);
wake_up_interruptible(&state->info->delta_msr_wait);
}
mutex_unlock(&state->mutex);
@@ -1421,7 +1422,7 @@ static void uart_hangup(struct tty_struct *tty)
*/
static void uart_update_termios(struct uart_state *state)
{
- struct tty_struct *tty = state->info->tty;
+ struct tty_struct *tty = state->info->port.tty;
struct uart_port *port = state->port;

if (uart_console(port) && port->cons->cflag) {
@@ -1460,17 +1461,17 @@ uart_block_til_ready(struct file *filp, struct uart_state *state)
struct uart_port *port = state->port;
unsigned int mctrl;

- info->blocked_open++;
+ info->port.blocked_open++;
state->count--;

- add_wait_queue(&info->open_wait, &wait);
+ add_wait_queue(&info->port.open_wait, &wait);
while (1) {
set_current_state(TASK_INTERRUPTIBLE);

/*
* If we have been hung up, tell userspace/restart open.
*/
- if (tty_hung_up_p(filp) || info->tty == NULL)
+ if (tty_hung_up_p(filp) || info->port.tty == NULL)
break;

/*
@@ -1489,8 +1490,8 @@ uart_block_til_ready(struct file *filp, struct uart_state *state)
* have set TTY_IO_ERROR for a non-existant port.
*/
if ((filp->f_flags & O_NONBLOCK) ||
- (info->tty->termios->c_cflag & CLOCAL) ||
- (info->tty->flags & (1 << TTY_IO_ERROR)))
+ (info->port.tty->termios->c_cflag & CLOCAL) ||
+ (info->port.tty->flags & (1 << TTY_IO_ERROR)))
break;

/*
@@ -1498,7 +1499,7 @@ uart_block_til_ready(struct file *filp, struct uart_state *state)
* not set RTS here - we want to make sure we catch
* the data from the modem.
*/
- if (info->tty->termios->c_cflag & CBAUD)
+ if (info->port.tty->termios->c_cflag & CBAUD)
uart_set_mctrl(port, TIOCM_DTR);

/*
@@ -1520,15 +1521,15 @@ uart_block_til_ready(struct file *filp, struct uart_state *state)
break;
}
set_current_state(TASK_RUNNING);
- remove_wait_queue(&info->open_wait, &wait);
+ remove_wait_queue(&info->port.open_wait, &wait);

state->count++;
- info->blocked_open--;
+ info->port.blocked_open--;

if (signal_pending(current))
return -ERESTARTSYS;

- if (!info->tty || tty_hung_up_p(filp))
+ if (!info->port.tty || tty_hung_up_p(filp))
return -EAGAIN;

return 0;
@@ -1551,10 +1552,13 @@ static struct uart_state *uart_get(struct uart_driver *drv, int line)
goto err_unlock;
}

+ /* BKL: RACE HERE - LEAK */
+ /* We should move this into the uart_state structure and kill off
+ this whole complexity */
if (!state->info) {
state->info = kzalloc(sizeof(struct uart_info), GFP_KERNEL);
if (state->info) {
- init_waitqueue_head(&state->info->open_wait);
+ init_waitqueue_head(&state->info->port.open_wait);
init_waitqueue_head(&state->info->delta_msr_wait);

/*
@@ -1611,7 +1615,7 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
* be re-entered while allocating the info structure, or while we
* request any IRQs that the driver may need. This also has the nice
* side-effect that it delays the action of uart_hangup, so we can
- * guarantee that info->tty will always contain something reasonable.
+ * guarantee that info->port.tty will always contain something reasonable.
*/
state = uart_get(drv, line);
if (IS_ERR(state)) {
@@ -1627,7 +1631,7 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
tty->driver_data = state;
tty->low_latency = (state->port->flags & UPF_LOW_LATENCY) ? 1 : 0;
tty->alt_speed = 0;
- state->info->tty = tty;
+ state->info->port.tty = tty;

/*
* If the port is in the middle of closing, bail out now.
@@ -2085,8 +2089,8 @@ int uart_resume_port(struct uart_driver *drv, struct uart_port *port)
/*
* If that's unset, use the tty termios setting.
*/
- if (state->info && state->info->tty && termios.c_cflag == 0)
- termios = *state->info->tty->termios;
+ if (state->info && state->info->port.tty && termios.c_cflag == 0)
+ termios = *state->info->port.tty->termios;

uart_change_pm(state, 0);
port->ops->set_termios(port, &termios, NULL);
@@ -2504,8 +2508,8 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *port)
tty_unregister_device(drv->tty_driver, port->line);

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

/*
* All users of this port should now be disconnected from
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index d32123a..2fbe004 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -342,13 +342,15 @@ typedef unsigned int __bitwise__ uif_t;
* stuff here.
*/
struct uart_info {
- struct tty_struct *tty;
+ struct tty_port port;
struct circ_buf xmit;
uif_t flags;

/*
* Definitions for info->flags. These are _private_ to serial_core, and
* are specific to this structure. They may be queried by low level drivers.
+ *
+ * FIXME: use the ASY_ definitions
*/
#define UIF_CHECK_CD ((__force uif_t) (1 << 25))
#define UIF_CTS_FLOW ((__force uif_t) (1 << 26))
@@ -356,11 +358,7 @@ struct uart_info {
#define UIF_INITIALIZED ((__force uif_t) (1 << 31))
#define UIF_SUSPENDED ((__force uif_t) (1 << 30))

- int blocked_open;
-
struct tasklet_struct tlet;
-
- wait_queue_head_t open_wait;
wait_queue_head_t delta_msr_wait;
};

@@ -437,8 +435,8 @@ int uart_resume_port(struct uart_driver *reg, struct uart_port *port);
#define uart_circ_chars_free(circ) \
(CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE))

-#define uart_tx_stopped(port) \
- ((port)->info->tty->stopped || (port)->info->tty->hw_stopped)
+#define uart_tx_stopped(portp) \
+ ((portp)->info->port.tty->stopped || (portp)->info->port.tty->hw_stopped)

/*
* The following are helper functions for the low level drivers.
@@ -449,7 +447,7 @@ uart_handle_sysrq_char(struct uart_port *port, unsigned int ch)
#ifdef SUPPORT_SYSRQ
if (port->sysrq) {
if (ch && time_before(jiffies, port->sysrq)) {
- handle_sysrq(ch, port->info ? port->info->tty : NULL);
+ handle_sysrq(ch, port->info ? port->info->port.tty : NULL);
port->sysrq = 0;
return 1;
}
@@ -478,7 +476,7 @@ static inline int uart_handle_break(struct uart_port *port)
}
#endif
if (port->flags & UPF_SAK)
- do_SAK(info->tty);
+ do_SAK(info->port.tty);
return 0;
}

@@ -501,9 +499,9 @@ uart_handle_dcd_change(struct uart_port *port, unsigned int status)

if (info->flags & UIF_CHECK_CD) {
if (status)
- wake_up_interruptible(&info->open_wait);
- else if (info->tty)
- tty_hangup(info->tty);
+ wake_up_interruptible(&info->port.open_wait);
+ else if (info->port.tty)
+ tty_hangup(info->port.tty);
}
}

@@ -516,7 +514,7 @@ static inline void
uart_handle_cts_change(struct uart_port *port, unsigned int status)
{
struct uart_info *info = port->info;
- struct tty_struct *tty = info->tty;
+ struct tty_struct *tty = info->port.tty;

port->icount.cts++;

@@ -542,7 +540,7 @@ static inline void
uart_insert_char(struct uart_port *port, unsigned int status,
unsigned int overrun, unsigned int ch, unsigned int flag)
{
- struct tty_struct *tty = port->info->tty;
+ struct tty_struct *tty = port->info->port.tty;

if ((status & port->ignore_status_mask & ~overrun) == 0)
tty_insert_flip_char(tty, ch, flag);