TTY: pty, cleanup the pty counting
Instead of the hackish way of counting ptys, let's define a specific
->remove hook both from slave and master. And decrease the count only
for master.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index e18604b..d8653ab 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -446,19 +446,8 @@
int pty_limit = NR_UNIX98_PTY_DEFAULT;
static int pty_limit_min;
static int pty_limit_max = NR_UNIX98_PTY_MAX;
-static int tty_count;
static int pty_count;
-static inline void pty_inc_count(void)
-{
- pty_count = (++tty_count) / 2;
-}
-
-static inline void pty_dec_count(void)
-{
- pty_count = (--tty_count) / 2;
-}
-
static struct cdev ptmx_cdev;
static struct ctl_table pty_table[] = {
@@ -600,8 +589,7 @@
*/
tty_driver_kref_get(driver);
tty->count++;
- pty_inc_count(); /* tty */
- pty_inc_count(); /* tty->link */
+ pty_count++;
return 0;
err_free_mem:
deinitialize_tty_struct(o_tty);
@@ -613,15 +601,19 @@
return -ENOMEM;
}
-static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
+static void ptm_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
{
- pty_dec_count();
+ pty_count--;
+}
+
+static void pts_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
+{
}
static const struct tty_operations ptm_unix98_ops = {
.lookup = ptm_unix98_lookup,
.install = pty_unix98_install,
- .remove = pty_unix98_remove,
+ .remove = ptm_unix98_remove,
.open = pty_open,
.close = pty_close,
.write = pty_write,
@@ -638,7 +630,7 @@
static const struct tty_operations pty_unix98_ops = {
.lookup = pts_unix98_lookup,
.install = pty_unix98_install,
- .remove = pty_unix98_remove,
+ .remove = pts_unix98_remove,
.open = pty_open,
.close = pty_close,
.write = pty_write,