TTY: ircomm, use tty from tty_port

This also includes a switch to tty refcounting. It makes sure, the
code no longer can access a freed TTY struct.

Sometimes the only thing needed is to pass tty down to the callies.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jiri Slaby 2012-06-04 13:35:21 +02:00 committed by Greg Kroah-Hartman
parent e673927d8a
commit 62f228acb8
5 changed files with 70 additions and 42 deletions

View File

@ -62,7 +62,6 @@ struct ircomm_tty_cb {
int state; /* Connect state */
struct tty_struct *tty;
struct ircomm_cb *ircomm; /* IrCOMM layer instance */
struct sk_buff *tx_skb; /* Transmit buffer */

View File

@ -99,7 +99,6 @@ pi_param_info_t ircomm_param_info = { pi_major_call_table, 3, 0x0f, 4 };
*/
int ircomm_param_request(struct ircomm_tty_cb *self, __u8 pi, int flush)
{
struct tty_struct *tty;
unsigned long flags;
struct sk_buff *skb;
int count;
@ -109,10 +108,6 @@ int ircomm_param_request(struct ircomm_tty_cb *self, __u8 pi, int flush)
IRDA_ASSERT(self != NULL, return -1;);
IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
tty = self->tty;
if (!tty)
return 0;
/* Make sure we don't send parameters for raw mode */
if (self->service_type == IRCOMM_3_WIRE_RAW)
return 0;

View File

@ -242,18 +242,15 @@ static int ircomm_tty_startup(struct ircomm_tty_cb *self)
*
*/
static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self,
struct file *filp)
struct tty_struct *tty, struct file *filp)
{
DECLARE_WAITQUEUE(wait, current);
int retval;
int do_clocal = 0, extra_count = 0;
unsigned long flags;
struct tty_struct *tty;
IRDA_DEBUG(2, "%s()\n", __func__ );
tty = self->tty;
/*
* If non-blocking mode is set, or the port is not enabled,
* then make the check up front and then exit.
@ -412,8 +409,8 @@ static int ircomm_tty_open(struct tty_struct *tty, struct file *filp)
self->port.count++;
tty->driver_data = self;
self->tty = tty;
spin_unlock_irqrestore(&self->port.lock, flags);
tty_port_tty_set(&self->port, tty);
IRDA_DEBUG(1, "%s(), %s%d, count = %d\n", __func__ , tty->driver->name,
self->line, self->port.count);
@ -467,7 +464,7 @@ static int ircomm_tty_open(struct tty_struct *tty, struct file *filp)
if (ret)
return ret;
ret = ircomm_tty_block_til_ready(self, filp);
ret = ircomm_tty_block_til_ready(self, tty, filp);
if (ret) {
IRDA_DEBUG(2,
"%s(), returning after block_til_ready with %d\n", __func__ ,
@ -548,7 +545,6 @@ static void ircomm_tty_close(struct tty_struct *tty, struct file *filp)
spin_lock_irqsave(&self->port.lock, flags);
tty->closing = 0;
self->tty = NULL;
if (self->port.blocked_open) {
if (self->port.close_delay) {
@ -562,6 +558,7 @@ static void ircomm_tty_close(struct tty_struct *tty, struct file *filp)
self->port.flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
spin_unlock_irqrestore(&self->port.lock, flags);
wake_up_interruptible(&self->port.close_wait);
tty_port_tty_set(&self->port, NULL);
}
/*
@ -604,7 +601,7 @@ static void ircomm_tty_do_softint(struct work_struct *work)
if (!self || self->magic != IRCOMM_TTY_MAGIC)
return;
tty = self->tty;
tty = tty_port_tty_get(&self->port);
if (!tty)
return;
@ -625,7 +622,7 @@ static void ircomm_tty_do_softint(struct work_struct *work)
}
if (tty->hw_stopped)
return;
goto put;
/* Unlink transmit buffer */
spin_lock_irqsave(&self->spinlock, flags);
@ -644,6 +641,8 @@ static void ircomm_tty_do_softint(struct work_struct *work)
/* Check if user (still) wants to be waken up */
tty_wakeup(tty);
put:
tty_kref_put(tty);
}
/*
@ -1004,7 +1003,11 @@ static void ircomm_tty_hangup(struct tty_struct *tty)
spin_lock_irqsave(&self->port.lock, flags);
self->port.flags &= ~ASYNC_NORMAL_ACTIVE;
self->tty = NULL;
if (self->port.tty) {
set_bit(TTY_IO_ERROR, &self->port.tty->flags);
tty_kref_put(self->port.tty);
}
self->port.tty = NULL;
self->port.count = 0;
spin_unlock_irqrestore(&self->port.lock, flags);
@ -1068,7 +1071,7 @@ void ircomm_tty_check_modem_status(struct ircomm_tty_cb *self)
IRDA_ASSERT(self != NULL, return;);
IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
tty = self->tty;
tty = tty_port_tty_get(&self->port);
status = self->settings.dce;
@ -1089,10 +1092,10 @@ void ircomm_tty_check_modem_status(struct ircomm_tty_cb *self)
tty_hangup(tty);
/* Hangup will remote the tty, so better break out */
return;
goto put;
}
}
if (self->port.flags & ASYNC_CTS_FLOW) {
if (tty && self->port.flags & ASYNC_CTS_FLOW) {
if (tty->hw_stopped) {
if (status & IRCOMM_CTS) {
IRDA_DEBUG(2,
@ -1103,7 +1106,7 @@ void ircomm_tty_check_modem_status(struct ircomm_tty_cb *self)
wake_up_interruptible(&self->port.open_wait);
schedule_work(&self->tqueue);
return;
goto put;
}
} else {
if (!(status & IRCOMM_CTS)) {
@ -1113,6 +1116,8 @@ void ircomm_tty_check_modem_status(struct ircomm_tty_cb *self)
}
}
}
put:
tty_kref_put(tty);
}
/*
@ -1125,6 +1130,7 @@ static int ircomm_tty_data_indication(void *instance, void *sap,
struct sk_buff *skb)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance;
struct tty_struct *tty;
IRDA_DEBUG(2, "%s()\n", __func__ );
@ -1132,7 +1138,8 @@ static int ircomm_tty_data_indication(void *instance, void *sap,
IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
IRDA_ASSERT(skb != NULL, return -1;);
if (!self->tty) {
tty = tty_port_tty_get(&self->port);
if (!tty) {
IRDA_DEBUG(0, "%s(), no tty!\n", __func__ );
return 0;
}
@ -1143,7 +1150,7 @@ static int ircomm_tty_data_indication(void *instance, void *sap,
* Devices like WinCE can do this, and since they don't send any
* params, we can just as well declare the hardware for running.
*/
if (self->tty->hw_stopped && (self->flow == FLOW_START)) {
if (tty->hw_stopped && (self->flow == FLOW_START)) {
IRDA_DEBUG(0, "%s(), polling for line settings!\n", __func__ );
ircomm_param_request(self, IRCOMM_POLL, TRUE);
@ -1156,8 +1163,9 @@ static int ircomm_tty_data_indication(void *instance, void *sap,
* Use flip buffer functions since the code may be called from interrupt
* context
*/
tty_insert_flip_string(self->tty, skb->data, skb->len);
tty_flip_buffer_push(self->tty);
tty_insert_flip_string(tty, skb->data, skb->len);
tty_flip_buffer_push(tty);
tty_kref_put(tty);
/* No need to kfree_skb - see ircomm_ttp_data_indication() */
@ -1208,12 +1216,13 @@ static void ircomm_tty_flow_indication(void *instance, void *sap,
IRDA_ASSERT(self != NULL, return;);
IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
tty = self->tty;
tty = tty_port_tty_get(&self->port);
switch (cmd) {
case FLOW_START:
IRDA_DEBUG(2, "%s(), hw start!\n", __func__ );
tty->hw_stopped = 0;
if (tty)
tty->hw_stopped = 0;
/* ircomm_tty_do_softint will take care of the rest */
schedule_work(&self->tqueue);
@ -1221,15 +1230,19 @@ static void ircomm_tty_flow_indication(void *instance, void *sap,
default: /* If we get here, something is very wrong, better stop */
case FLOW_STOP:
IRDA_DEBUG(2, "%s(), hw stopped!\n", __func__ );
tty->hw_stopped = 1;
if (tty)
tty->hw_stopped = 1;
break;
}
tty_kref_put(tty);
self->flow = cmd;
}
#ifdef CONFIG_PROC_FS
static void ircomm_tty_line_info(struct ircomm_tty_cb *self, struct seq_file *m)
{
struct tty_struct *tty;
char sep;
seq_printf(m, "State: %s\n", ircomm_tty_state[self->state]);
@ -1356,9 +1369,12 @@ static void ircomm_tty_line_info(struct ircomm_tty_cb *self, struct seq_file *m)
seq_printf(m, "Max data size: %d\n", self->max_data_size);
seq_printf(m, "Max header size: %d\n", self->max_header_size);
if (self->tty)
tty = tty_port_tty_get(&self->port);
if (tty) {
seq_printf(m, "Hardware: %s\n",
self->tty->hw_stopped ? "Stopped" : "Running");
tty->hw_stopped ? "Stopped" : "Running");
tty_kref_put(tty);
}
}
static int ircomm_tty_proc_show(struct seq_file *m, void *v)

View File

@ -130,6 +130,8 @@ static int (*state[])(struct ircomm_tty_cb *self, IRCOMM_TTY_EVENT event,
*/
int ircomm_tty_attach_cable(struct ircomm_tty_cb *self)
{
struct tty_struct *tty;
IRDA_DEBUG(0, "%s()\n", __func__ );
IRDA_ASSERT(self != NULL, return -1;);
@ -142,7 +144,11 @@ int ircomm_tty_attach_cable(struct ircomm_tty_cb *self)
}
/* Make sure nobody tries to write before the link is up */
self->tty->hw_stopped = 1;
tty = tty_port_tty_get(&self->port);
if (tty) {
tty->hw_stopped = 1;
tty_kref_put(tty);
}
ircomm_tty_ias_register(self);
@ -398,23 +404,26 @@ void ircomm_tty_disconnect_indication(void *instance, void *sap,
struct sk_buff *skb)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance;
struct tty_struct *tty;
IRDA_DEBUG(2, "%s()\n", __func__ );
IRDA_ASSERT(self != NULL, return;);
IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
if (!self->tty)
tty = tty_port_tty_get(&self->port);
if (!tty)
return;
/* This will stop control data transfers */
self->flow = FLOW_STOP;
/* Stop data transfers */
self->tty->hw_stopped = 1;
tty->hw_stopped = 1;
ircomm_tty_do_event(self, IRCOMM_TTY_DISCONNECT_INDICATION, NULL,
NULL);
tty_kref_put(tty);
}
/*
@ -550,12 +559,15 @@ void ircomm_tty_connect_indication(void *instance, void *sap,
*/
void ircomm_tty_link_established(struct ircomm_tty_cb *self)
{
struct tty_struct *tty;
IRDA_DEBUG(2, "%s()\n", __func__ );
IRDA_ASSERT(self != NULL, return;);
IRDA_ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
if (!self->tty)
tty = tty_port_tty_get(&self->port);
if (!tty)
return;
del_timer(&self->watchdog_timer);
@ -569,17 +581,19 @@ void ircomm_tty_link_established(struct ircomm_tty_cb *self)
if ((self->port.flags & ASYNC_CTS_FLOW) &&
((self->settings.dce & IRCOMM_CTS) == 0)) {
IRDA_DEBUG(0, "%s(), waiting for CTS ...\n", __func__ );
return;
goto put;
} else {
IRDA_DEBUG(1, "%s(), starting hardware!\n", __func__ );
self->tty->hw_stopped = 0;
tty->hw_stopped = 0;
/* Wake up processes blocked on open */
wake_up_interruptible(&self->port.open_wait);
}
schedule_work(&self->tqueue);
put:
tty_kref_put(tty);
}
/*
@ -983,9 +997,12 @@ static int ircomm_tty_state_ready(struct ircomm_tty_cb *self,
self->settings.dce = IRCOMM_DELTA_CD;
ircomm_tty_check_modem_status(self);
} else {
struct tty_struct *tty = tty_port_tty_get(&self->port);
IRDA_DEBUG(0, "%s(), hanging up!\n", __func__ );
if (self->tty)
tty_hangup(self->tty);
if (tty) {
tty_hangup(tty);
tty_kref_put(tty);
}
}
break;
default:

View File

@ -52,17 +52,18 @@
* Change speed of the driver. If the remote device is a DCE, then this
* should make it change the speed of its serial port
*/
static void ircomm_tty_change_speed(struct ircomm_tty_cb *self)
static void ircomm_tty_change_speed(struct ircomm_tty_cb *self,
struct tty_struct *tty)
{
unsigned int cflag, cval;
int baud;
IRDA_DEBUG(2, "%s()\n", __func__ );
if (!self->tty || !self->tty->termios || !self->ircomm)
if (!self->ircomm)
return;
cflag = self->tty->termios->c_cflag;
cflag = tty->termios->c_cflag;
/* byte size and parity */
switch (cflag & CSIZE) {
@ -81,7 +82,7 @@ static void ircomm_tty_change_speed(struct ircomm_tty_cb *self)
cval |= IRCOMM_PARITY_EVEN;
/* Determine divisor based on baud rate */
baud = tty_get_baud_rate(self->tty);
baud = tty_get_baud_rate(tty);
if (!baud)
baud = 9600; /* B0 transition handled in rs_set_termios */
@ -159,7 +160,7 @@ void ircomm_tty_set_termios(struct tty_struct *tty,
return;
}
ircomm_tty_change_speed(self);
ircomm_tty_change_speed(self, tty);
/* Handle transition to B0 status */
if ((old_termios->c_cflag & CBAUD) &&