diff options
| -rw-r--r-- | drivers/tty/serial/8250/8250_core.c | 37 |
1 files changed, 26 insertions, 11 deletions
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index 7a6050f1c094..d42ceb6ffdc2 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -129,11 +129,15 @@ static void serial_do_unlink(struct irq_info *i, struct uart_8250_port *up) } } -static int serial_link_irq_chain(struct uart_8250_port *up) +/* + * Either: + * - find the corresponding info in the hashtable and return it, or + * - allocate a new one, add it to the hashtable and return it. + */ +static struct irq_info *serial_get_or_create_irq_info(const struct uart_8250_port *up) { struct hlist_head *h; struct irq_info *i; - int ret; mutex_lock(&hash_mutex); @@ -141,20 +145,31 @@ static int serial_link_irq_chain(struct uart_8250_port *up) hlist_for_each_entry(i, h, node) if (i->irq == up->port.irq) - break; + goto unlock; + i = kzalloc(sizeof(*i), GFP_KERNEL); if (i == NULL) { - i = kzalloc(sizeof(struct irq_info), GFP_KERNEL); - if (i == NULL) { - mutex_unlock(&hash_mutex); - return -ENOMEM; - } - spin_lock_init(&i->lock); - i->irq = up->port.irq; - hlist_add_head(&i->node, h); + i = ERR_PTR(-ENOMEM); + goto unlock; } + spin_lock_init(&i->lock); + i->irq = up->port.irq; + hlist_add_head(&i->node, h); +unlock: mutex_unlock(&hash_mutex); + return i; +} + +static int serial_link_irq_chain(struct uart_8250_port *up) +{ + struct irq_info *i; + int ret; + + i = serial_get_or_create_irq_info(up); + if (IS_ERR(i)) + return PTR_ERR(i); + spin_lock_irq(&i->lock); if (i->head) { |