aboutsummaryrefslogtreecommitdiffstats
path: root/arch/um/drivers/line.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/um/drivers/line.c')
-rw-r--r--arch/um/drivers/line.c61
1 files changed, 36 insertions, 25 deletions
diff --git a/arch/um/drivers/line.c b/arch/um/drivers/line.c
index d51c404..364c8a1 100644
--- a/arch/um/drivers/line.c
+++ b/arch/um/drivers/line.c
@@ -399,8 +399,8 @@ int line_setup_irq(int fd, int input, int output, struct line *line, void *data)
* is done under a spinlock. Checking whether the device is in use is
* line->tty->count > 1, also under the spinlock.
*
- * tty->count serves to decide whether the device should be enabled or
- * disabled on the host. If it's equal to 1, then we are doing the
+ * line->count serves to decide whether the device should be enabled or
+ * disabled on the host. If it's equal to 0, then we are doing the
* first open or last close. Otherwise, open and close just return.
*/
@@ -414,16 +414,16 @@ int line_open(struct line *lines, struct tty_struct *tty)
goto out_unlock;
err = 0;
- if (tty->count > 1)
+ if (line->count++)
goto out_unlock;
- spin_unlock(&line->count_lock);
-
+ BUG_ON(tty->driver_data);
tty->driver_data = line;
line->tty = tty;
+ spin_unlock(&line->count_lock);
err = enable_chan(line);
- if (err)
+ if (err) /* line_close() will be called by our caller */
return err;
INIT_DELAYED_WORK(&line->task, line_timer_cb);
@@ -436,7 +436,7 @@ int line_open(struct line *lines, struct tty_struct *tty)
chan_window_size(&line->chan_list, &tty->winsize.ws_row,
&tty->winsize.ws_col);
- return err;
+ return 0;
out_unlock:
spin_unlock(&line->count_lock);
@@ -460,17 +460,16 @@ void line_close(struct tty_struct *tty, struct file * filp)
flush_buffer(line);
spin_lock(&line->count_lock);
- if (!line->valid)
- goto out_unlock;
+ BUG_ON(!line->valid);
- if (tty->count > 1)
+ if (--line->count)
goto out_unlock;
- spin_unlock(&line->count_lock);
-
line->tty = NULL;
tty->driver_data = NULL;
+ spin_unlock(&line->count_lock);
+
if (line->sigio) {
unregister_winch(tty);
line->sigio = 0;
@@ -498,7 +497,7 @@ static int setup_one_line(struct line *lines, int n, char *init, int init_prio,
spin_lock(&line->count_lock);
- if (line->tty != NULL) {
+ if (line->count) {
*error_out = "Device is already open";
goto out;
}
@@ -722,41 +721,53 @@ struct winch {
int pid;
struct tty_struct *tty;
unsigned long stack;
+ struct work_struct work;
};
-static void free_winch(struct winch *winch, int free_irq_ok)
+static void __free_winch(struct work_struct *work)
{
- if (free_irq_ok)
- free_irq(WINCH_IRQ, winch);
-
- list_del(&winch->list);
+ struct winch *winch = container_of(work, struct winch, work);
+ free_irq(WINCH_IRQ, winch);
if (winch->pid != -1)
os_kill_process(winch->pid, 1);
- if (winch->fd != -1)
- os_close_file(winch->fd);
if (winch->stack != 0)
free_stack(winch->stack, 0);
kfree(winch);
}
+static void free_winch(struct winch *winch)
+{
+ int fd = winch->fd;
+ winch->fd = -1;
+ if (fd != -1)
+ os_close_file(fd);
+ list_del(&winch->list);
+ __free_winch(&winch->work);
+}
+
static irqreturn_t winch_interrupt(int irq, void *data)
{
struct winch *winch = data;
struct tty_struct *tty;
struct line *line;
+ int fd = winch->fd;
int err;
char c;
- if (winch->fd != -1) {
- err = generic_read(winch->fd, &c, NULL);
+ if (fd != -1) {
+ err = generic_read(fd, &c, NULL);
if (err < 0) {
if (err != -EAGAIN) {
+ winch->fd = -1;
+ list_del(&winch->list);
+ os_close_file(fd);
printk(KERN_ERR "winch_interrupt : "
"read failed, errno = %d\n", -err);
printk(KERN_ERR "fd %d is losing SIGWINCH "
"support\n", winch->tty_fd);
- free_winch(winch, 0);
+ INIT_WORK(&winch->work, __free_winch);
+ schedule_work(&winch->work);
return IRQ_HANDLED;
}
goto out;
@@ -828,7 +839,7 @@ static void unregister_winch(struct tty_struct *tty)
list_for_each_safe(ele, next, &winch_handlers) {
winch = list_entry(ele, struct winch, list);
if (winch->tty == tty) {
- free_winch(winch, 1);
+ free_winch(winch);
break;
}
}
@@ -844,7 +855,7 @@ static void winch_cleanup(void)
list_for_each_safe(ele, next, &winch_handlers) {
winch = list_entry(ele, struct winch, list);
- free_winch(winch, 1);
+ free_winch(winch);
}
spin_unlock(&winch_handler_lock);

Privacy Policy