genirq/manage: Rework irq_set_vcpu_affinity()

Use the new guards to get and lock the interrupt descriptor and tidy up the
code.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/all/87ikmlq0fk.ffs@tglx

Author: KAGA-KOKO

kernel/irq/manage.c

@@ -629,32 +629,25 @@ int irq_setup_affinity(struct irq_desc *desc)
  */
 int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info)
 {
-	unsigned long flags;
-	struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0);
-	struct irq_data *data;
-	struct irq_chip *chip;
-	int ret = -ENOSYS;
-
-	if (!desc)
-		return -EINVAL;
+	scoped_irqdesc_get_and_lock(irq, 0) {
+		struct irq_desc *desc = scoped_irqdesc;
+		struct irq_data *data;
+		struct irq_chip *chip;
 
-	data = irq_desc_get_irq_data(desc);
-	do {
-		chip = irq_data_get_irq_chip(data);
-		if (chip && chip->irq_set_vcpu_affinity)
-			break;
-#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
-		data = data->parent_data;
-#else
-		data = NULL;
-#endif
-	} while (data);
+		data = irq_desc_get_irq_data(desc);
+		do {
+			chip = irq_data_get_irq_chip(data);
+			if (chip && chip->irq_set_vcpu_affinity)
+				break;
 
-	if (data)
-		ret = chip->irq_set_vcpu_affinity(data, vcpu_info);
-	irq_put_desc_unlock(desc, flags);
+			data = irqd_get_parent_data(data);
+		} while (data);
 
-	return ret;
+		if (!data)
+			return -ENOSYS;
+		return chip->irq_set_vcpu_affinity(data, vcpu_info);
+	}
+	return -EINVAL;
 }
 EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity);