irqbypass: Use guard(mutex) in lieu of manual lock+unlock

Use guard(mutex) to clean up irqbypass's error handling.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20250516230734.2564775-7-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

diff --git a/virt/lib/irqbypass.c b/virt/lib/irqbypass.c
index 6a183459dc443ca58ca8354cd6ee5d4f5fe4c7e3..828556c081f51a35ef9cf384d8389a345af23807 100644 (file)
--- a/virt/lib/irqbypass.c
+++ b/virt/lib/irqbypass.c
@@ -99,33 +99,25 @@ int irq_bypass_register_producer(struct irq_bypass_producer *producer,
        if (WARN_ON_ONCE(producer->eventfd))
                return -EINVAL;
 
-       mutex_lock(&lock);
+       guard(mutex)(&lock);
 
        list_for_each_entry(tmp, &producers, node) {
-               if (tmp->eventfd == eventfd) {
-                       ret = -EBUSY;
-                       goto out_err;
-               }
+               if (tmp->eventfd == eventfd)
+                       return -EBUSY;
        }
 
        list_for_each_entry(consumer, &consumers, node) {
                if (consumer->eventfd == eventfd) {
                        ret = __connect(producer, consumer);
                        if (ret)
-                               goto out_err;
+                               return ret;
                        break;
                }
        }
 
        producer->eventfd = eventfd;
        list_add(&producer->node, &producers);
-
-       mutex_unlock(&lock);
-
        return 0;
-out_err:
-       mutex_unlock(&lock);
-       return ret;
 }
 EXPORT_SYMBOL_GPL(irq_bypass_register_producer);
 
@@ -141,14 +133,13 @@ void irq_bypass_unregister_producer(struct irq_bypass_producer *producer)
        if (!producer->eventfd)
                return;
 
-       mutex_lock(&lock);
+       guard(mutex)(&lock);
 
        if (producer->consumer)
                __disconnect(producer, producer->consumer);
 
        producer->eventfd = NULL;
        list_del(&producer->node);
-       mutex_unlock(&lock);
 }
 EXPORT_SYMBOL_GPL(irq_bypass_unregister_producer);
 
@@ -173,33 +164,25 @@ int irq_bypass_register_consumer(struct irq_bypass_consumer *consumer,
        if (!consumer->add_producer || !consumer->del_producer)
                return -EINVAL;
 
-       mutex_lock(&lock);
+       guard(mutex)(&lock);
 
        list_for_each_entry(tmp, &consumers, node) {
-               if (tmp->eventfd == eventfd) {
-                       ret = -EBUSY;
-                       goto out_err;
-               }
+               if (tmp->eventfd == eventfd)
+                       return -EBUSY;
        }
 
        list_for_each_entry(producer, &producers, node) {
                if (producer->eventfd == eventfd) {
                        ret = __connect(producer, consumer);
                        if (ret)
-                               goto out_err;
+                               return ret;
                        break;
                }
        }
 
        consumer->eventfd = eventfd;
        list_add(&consumer->node, &consumers);
-
-       mutex_unlock(&lock);
-
        return 0;
-out_err:
-       mutex_unlock(&lock);
-       return ret;
 }
 EXPORT_SYMBOL_GPL(irq_bypass_register_consumer);
 
@@ -215,13 +198,12 @@ void irq_bypass_unregister_consumer(struct irq_bypass_consumer *consumer)
        if (!consumer->eventfd)
                return;
 
-       mutex_lock(&lock);
+       guard(mutex)(&lock);
 
        if (consumer->producer)
                __disconnect(consumer->producer, consumer);
 
        consumer->eventfd = NULL;
        list_del(&consumer->node);
-       mutex_unlock(&lock);
 }
 EXPORT_SYMBOL_GPL(irq_bypass_unregister_consumer);