Commit 3e61696b authored by Alan Cox's avatar Alan Cox Committed by Linus Torvalds
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isicom: redo locking to use tty port locks



This helps set the basis for moving block_til_ready into common code. We also
introduce a tty_port_hangup helper as this will also be generally needed.
Signed-off-by: default avatarAlan Cox <alan@redhat.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 5d951fb4
......@@ -841,7 +841,6 @@ static int isicom_carrier_raised(struct tty_port *port)
static int block_til_ready(struct tty_struct *tty, struct file *filp,
struct isi_port *ip)
{
struct isi_board *card = ip->card;
struct tty_port *port = &ip->port;
int do_clocal = 0, retval;
unsigned long flags;
......@@ -876,11 +875,11 @@ static int block_til_ready(struct tty_struct *tty, struct file *filp,
retval = 0;
add_wait_queue(&port->open_wait, &wait);
spin_lock_irqsave(&card->card_lock, flags);
spin_lock_irqsave(&port->lock, flags);
if (!tty_hung_up_p(filp))
port->count--;
port->blocked_open++;
spin_unlock_irqrestore(&card->card_lock, flags);
spin_unlock_irqrestore(&port->lock, flags);
while (1) {
tty_port_raise_dtr_rts(port);
......@@ -905,14 +904,13 @@ static int block_til_ready(struct tty_struct *tty, struct file *filp,
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&port->open_wait, &wait);
spin_lock_irqsave(&card->card_lock, flags);
spin_lock_irqsave(&port->lock, flags);
if (!tty_hung_up_p(filp))
port->count++;
port->blocked_open--;
spin_unlock_irqrestore(&card->card_lock, flags);
if (retval)
return retval;
port->flags |= ASYNC_NORMAL_ACTIVE;
if (retval == 0)
port->flags |= ASYNC_NORMAL_ACTIVE;
spin_unlock_irqrestore(&port->lock, flags);
return 0;
}
......@@ -1034,9 +1032,9 @@ static void isicom_close(struct tty_struct *tty, struct file *filp)
pr_dbg("Close start!!!.\n");
spin_lock_irqsave(&card->card_lock, flags);
spin_lock_irqsave(&port->port.lock, flags);
if (tty_hung_up_p(filp)) {
spin_unlock_irqrestore(&card->card_lock, flags);
spin_unlock_irqrestore(&port->port.lock, flags);
return;
}
......@@ -1054,12 +1052,12 @@ static void isicom_close(struct tty_struct *tty, struct file *filp)
}
if (port->port.count) {
spin_unlock_irqrestore(&card->card_lock, flags);
spin_unlock_irqrestore(&port->port.lock, flags);
return;
}
port->port.flags |= ASYNC_CLOSING;
tty->closing = 1;
spin_unlock_irqrestore(&card->card_lock, flags);
spin_unlock_irqrestore(&port->port.lock, flags);
if (port->port.closing_wait != ASYNC_CLOSING_WAIT_NONE)
tty_wait_until_sent(tty, port->port.closing_wait);
......@@ -1076,22 +1074,22 @@ static void isicom_close(struct tty_struct *tty, struct file *filp)
isicom_flush_buffer(tty);
tty_ldisc_flush(tty);
spin_lock_irqsave(&card->card_lock, flags);
spin_lock_irqsave(&port->port.lock, flags);
tty->closing = 0;
if (port->port.blocked_open) {
spin_unlock_irqrestore(&card->card_lock, flags);
spin_unlock_irqrestore(&port->port.lock, flags);
if (port->port.close_delay) {
pr_dbg("scheduling until time out.\n");
msleep_interruptible(
jiffies_to_msecs(port->port.close_delay));
}
spin_lock_irqsave(&card->card_lock, flags);
spin_lock_irqsave(&port->port.lock, flags);
wake_up_interruptible(&port->port.open_wait);
}
port->port.flags &= ~(ASYNC_NORMAL_ACTIVE | ASYNC_CLOSING);
wake_up_interruptible(&port->port.close_wait);
spin_unlock_irqrestore(&card->card_lock, flags);
spin_unlock_irqrestore(&port->port.lock, flags);
}
/* write et all */
......@@ -1430,10 +1428,7 @@ static void isicom_hangup(struct tty_struct *tty)
isicom_shutdown_port(port);
spin_unlock_irqrestore(&port->card->card_lock, flags);
port->port.count = 0;
port->port.flags &= ~ASYNC_NORMAL_ACTIVE;
tty_port_tty_set(&port->port, NULL);
wake_up_interruptible(&port->port.open_wait);
tty_port_hangup(&port->port);
}
......
......@@ -3331,6 +3331,17 @@ static int carrier_raised(struct tty_port *port)
return (info->serial_signals & SerialSignal_DCD) ? 1 : 0;
}
static void raise_dtr_rts(struct tty_port *port)
{
SLMP_INFO *info = container_of(port, SLMP_INFO, port);
unsigned long flags;
spin_lock_irqsave(&info->lock,flags);
info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
set_signals(info);
spin_unlock_irqrestore(&info->lock,flags);
}
/* Block the current process until the specified port is ready to open.
*/
static int block_til_ready(struct tty_struct *tty, struct file *filp,
......@@ -3381,12 +3392,8 @@ static int block_til_ready(struct tty_struct *tty, struct file *filp,
port->blocked_open++;
while (1) {
if ((tty->termios->c_cflag & CBAUD)) {
spin_lock_irqsave(&info->lock,flags);
info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
set_signals(info);
spin_unlock_irqrestore(&info->lock,flags);
}
if (tty->termios->c_cflag & CBAUD)
tty_port_raise_dtr_rts(port);
set_current_state(TASK_INTERRUPTIBLE);
......@@ -3793,6 +3800,7 @@ static void add_device(SLMP_INFO *info)
static const struct tty_port_operations port_ops = {
.carrier_raised = carrier_raised,
.raise_dtr_rts = raise_dtr_rts,
};
/* Allocate and initialize a device instance structure
......
......@@ -7,6 +7,7 @@
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/serial.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/slab.h>
......@@ -95,6 +96,29 @@ void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty)
}
EXPORT_SYMBOL(tty_port_tty_set);
/**
* tty_port_hangup - hangup helper
* @port: tty port
*
* Perform port level tty hangup flag and count changes. Drop the tty
* reference.
*/
void tty_port_hangup(struct tty_port *port)
{
unsigned long flags;
spin_lock_irqsave(&port->lock, flags);
port->count = 0;
port->flags &= ~ASYNC_NORMAL_ACTIVE;
if (port->tty)
tty_kref_put(port->tty);
port->tty = NULL;
spin_unlock_irqrestore(&port->lock, flags);
wake_up_interruptible(&port->open_wait);
}
EXPORT_SYMBOL(tty_port_hangup);
/**
* tty_port_carrier_raised - carrier raised check
* @port: tty port
......
......@@ -438,6 +438,7 @@ extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
extern int tty_port_carrier_raised(struct tty_port *port);
extern void tty_port_raise_dtr_rts(struct tty_port *port);
extern void tty_port_hangup(struct tty_port *port);
extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
extern int tty_unregister_ldisc(int disc);
......
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