diff options
Diffstat (limited to 'drivers/char/tty_ldisc.c')
| -rw-r--r-- | drivers/char/tty_ldisc.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/drivers/char/tty_ldisc.c b/drivers/char/tty_ldisc.c index be55dfcf59ac..1733d3439ad2 100644 --- a/drivers/char/tty_ldisc.c +++ b/drivers/char/tty_ldisc.c @@ -55,25 +55,32 @@ static inline struct tty_ldisc *get_ldisc(struct tty_ldisc *ld) return ld; } -static inline void put_ldisc(struct tty_ldisc *ld) +static void put_ldisc(struct tty_ldisc *ld) { + unsigned long flags; + if (WARN_ON_ONCE(!ld)) return; /* * If this is the last user, free the ldisc, and * release the ldisc ops. + * + * We really want an "atomic_dec_and_lock_irqsave()", + * but we don't have it, so this does it by hand. */ - if (atomic_dec_and_test(&ld->users)) { - unsigned long flags; + local_irq_save(flags); + if (atomic_dec_and_lock(&ld->users, &tty_ldisc_lock)) { struct tty_ldisc_ops *ldo = ld->ops; - kfree(ld); - spin_lock_irqsave(&tty_ldisc_lock, flags); ldo->refcount--; module_put(ldo->owner); spin_unlock_irqrestore(&tty_ldisc_lock, flags); + + kfree(ld); + return; } + local_irq_restore(flags); } /** |