irq_domain/powerpc: Eliminate virq_is_host()

There is only one user, and it is trivial to open-code.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: Olof Johansson <olof@lixom.net>

arch/powerpc/include/asm/irq.h

@@ -58,7 +58,6 @@ extern atomic_t ppc_n_lost_interrupts;
 struct irq_data;
 extern irq_hw_number_t irqd_to_hwirq(struct irq_data *d);
 extern irq_hw_number_t virq_to_hw(unsigned int virq);
-extern bool virq_is_host(unsigned int virq, struct irq_domain *host);
 
 /**
  * irq_alloc_host - Allocate a new irq_domain data structure

arch/powerpc/kernel/irq.c

@@ -510,13 +510,6 @@ irq_hw_number_t virq_to_hw(unsigned int virq)
 }
 EXPORT_SYMBOL_GPL(virq_to_hw);
 
-bool virq_is_host(unsigned int virq, struct irq_domain *host)
-{
-	struct irq_data *irq_data = irq_get_irq_data(virq);
-	return irq_data ? irq_data->domain == host : false;
-}
-EXPORT_SYMBOL_GPL(virq_is_host);
-
 static int default_irq_host_match(struct irq_domain *h, struct device_node *np)
 {
 	return h->of_node != NULL && h->of_node == np;

arch/powerpc/sysdev/xics/xics-common.c

@@ -212,16 +212,16 @@ void xics_migrate_irqs_away(void)
 		/* We can't set affinity on ISA interrupts */
 		if (virq < NUM_ISA_INTERRUPTS)
 			continue;
-		if (!virq_is_host(virq, xics_host))
-			continue;
-		irq = (unsigned int)virq_to_hw(virq);
-		/* We need to get IPIs still. */
-		if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
-			continue;
 		desc = irq_to_desc(virq);
 		/* We only need to migrate enabled IRQS */
 		if (!desc || !desc->action)
 			continue;
+		if (desc->irq_data.domain != xics_host)
+			continue;
+		irq = desc->irq_data.hwirq;
+		/* We need to get IPIs still. */
+		if (irq == XICS_IPI || irq == XICS_IRQ_SPURIOUS)
+			continue;
 		chip = irq_desc_get_chip(desc);
 		if (!chip || !chip->irq_set_affinity)
 			continue;