diff options
Diffstat (limited to 'drivers/tty/serial/8250/8250_core.c')
| -rw-r--r-- | drivers/tty/serial/8250/8250_core.c | 93 |
1 files changed, 37 insertions, 56 deletions
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c index feb920c5b2e8..bfa421ab3253 100644 --- a/drivers/tty/serial/8250/8250_core.c +++ b/drivers/tty/serial/8250/8250_core.c @@ -72,7 +72,7 @@ static irqreturn_t serial8250_interrupt(int irq, void *dev_id) struct list_head *l, *end = NULL; int pass_counter = 0, handled = 0; - spin_lock(&i->lock); + guard(spinlock)(&i->lock); l = i->head; do { @@ -91,8 +91,6 @@ static irqreturn_t serial8250_interrupt(int irq, void *dev_id) break; } while (l != end); - spin_unlock(&i->lock); - return IRQ_RETVAL(handled); } @@ -132,22 +130,19 @@ static struct irq_info *serial_get_or_create_irq_info(const struct uart_8250_por { struct irq_info *i; - mutex_lock(&hash_mutex); + guard(mutex)(&hash_mutex); hash_for_each_possible(irq_lists, i, node, up->port.irq) if (i->irq == up->port.irq) - goto unlock; + return i; i = kzalloc(sizeof(*i), GFP_KERNEL); - if (i == NULL) { - i = ERR_PTR(-ENOMEM); - goto unlock; - } + if (i == NULL) + return ERR_PTR(-ENOMEM); + spin_lock_init(&i->lock); i->irq = up->port.irq; hash_add(irq_lists, &i->node, i->irq); -unlock: - mutex_unlock(&hash_mutex); return i; } @@ -161,23 +156,21 @@ static int serial_link_irq_chain(struct uart_8250_port *up) if (IS_ERR(i)) return PTR_ERR(i); - spin_lock_irq(&i->lock); + scoped_guard(spinlock_irq, &i->lock) { + if (i->head) { + list_add(&up->list, i->head); - if (i->head) { - list_add(&up->list, i->head); - spin_unlock_irq(&i->lock); + return 0; + } - ret = 0; - } else { INIT_LIST_HEAD(&up->list); i->head = &up->list; - spin_unlock_irq(&i->lock); - ret = request_irq(up->port.irq, serial8250_interrupt, - up->port.irqflags, up->port.name, i); - if (ret < 0) - serial_do_unlink(i, up); } + ret = request_irq(up->port.irq, serial8250_interrupt, up->port.irqflags, up->port.name, i); + if (ret < 0) + serial_do_unlink(i, up); + return ret; } @@ -185,20 +178,22 @@ static void serial_unlink_irq_chain(struct uart_8250_port *up) { struct irq_info *i; - mutex_lock(&hash_mutex); + guard(mutex)(&hash_mutex); hash_for_each_possible(irq_lists, i, node, up->port.irq) - if (i->irq == up->port.irq) - break; + if (i->irq == up->port.irq) { + if (WARN_ON(i->head == NULL)) + return; - BUG_ON(i == NULL); - BUG_ON(i->head == NULL); + if (list_empty(i->head)) + free_irq(up->port.irq, i); - if (list_empty(i->head)) - free_irq(up->port.irq, i); + serial_do_unlink(i, up); + + return; + } - serial_do_unlink(i, up); - mutex_unlock(&hash_mutex); + WARN_ON(1); } /* @@ -307,7 +302,7 @@ static void univ8250_release_irq(struct uart_8250_port *up) serial_unlink_irq_chain(up); } -const struct uart_ops *univ8250_port_base_ops = NULL; +const struct uart_ops *univ8250_port_base_ops; struct uart_ops univ8250_port_ops; static const struct uart_8250_ops univ8250_driver_ops = { @@ -670,16 +665,12 @@ static struct uart_8250_port *serial8250_find_match_or_unused(const struct uart_ static void serial_8250_overrun_backoff_work(struct work_struct *work) { - struct uart_8250_port *up = - container_of(to_delayed_work(work), struct uart_8250_port, - overrun_backoff); - struct uart_port *port = &up->port; - unsigned long flags; + struct uart_8250_port *up = container_of(to_delayed_work(work), struct uart_8250_port, + overrun_backoff); - uart_port_lock_irqsave(port, &flags); + guard(uart_port_lock_irqsave)(&up->port); up->ier |= UART_IER_RLSI | UART_IER_RDI; serial_out(up, UART_IER, up->ier); - uart_port_unlock_irqrestore(port, flags); } /** @@ -698,12 +689,12 @@ static void serial_8250_overrun_backoff_work(struct work_struct *work) int serial8250_register_8250_port(const struct uart_8250_port *up) { struct uart_8250_port *uart; - int ret = -ENOSPC; + int ret; if (up->port.uartclk == 0) return -EINVAL; - mutex_lock(&serial_mutex); + guard(mutex)(&serial_mutex); uart = serial8250_find_match_or_unused(&up->port); if (!uart) { @@ -713,15 +704,13 @@ int serial8250_register_8250_port(const struct uart_8250_port *up) */ uart = serial8250_setup_port(nr_uarts); if (!uart) - goto unlock; + return -ENOSPC; nr_uarts++; } /* Check if it is CIR already. We check this below again, see there why. */ - if (uart->port.type == PORT_8250_CIR) { - ret = -ENODEV; - goto unlock; - } + if (uart->port.type == PORT_8250_CIR) + return -ENODEV; if (uart->port.dev) uart_remove_one_port(&serial8250_reg, &uart->port); @@ -855,14 +844,10 @@ int serial8250_register_8250_port(const struct uart_8250_port *up) uart->overrun_backoff_time_ms = 0; } -unlock: - mutex_unlock(&serial_mutex); - return ret; err: uart->port.dev = NULL; - mutex_unlock(&serial_mutex); return ret; } EXPORT_SYMBOL(serial8250_register_8250_port); @@ -878,14 +863,11 @@ void serial8250_unregister_port(int line) { struct uart_8250_port *uart = &serial8250_ports[line]; - mutex_lock(&serial_mutex); + guard(mutex)(&serial_mutex); if (uart->em485) { - unsigned long flags; - - uart_port_lock_irqsave(&uart->port, &flags); + guard(uart_port_lock_irqsave)(&uart->port); serial8250_em485_destroy(uart); - uart_port_unlock_irqrestore(&uart->port, flags); } uart_remove_one_port(&serial8250_reg, &uart->port); @@ -901,7 +883,6 @@ void serial8250_unregister_port(int line) } else { uart->port.dev = NULL; } - mutex_unlock(&serial_mutex); } EXPORT_SYMBOL(serial8250_unregister_port); |