x86/htirq: Use new irqdomain interfaces to allocate/free IRQ

Use new irqdomain interfaces to allocate/free IRQ for HTIRQ, so we can
remove GENERIC_IRQ_LEGACY_ALLOC_HWIRQ later.

This patch changes the interfaces between arch independent PCI driver
and arch specific code. Currently HT_IRQ is only enabled on x86, so it
does not affect other architectures.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Cohen <david.a.cohen@linux.intel.com>
Cc: Sander Eikelenboom <linux@eikelenboom.it>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Link: http://lkml.kernel.org/r/1428905519-23704-7-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/kernel/apic/htirq.c

@@ -14,6 +14,7 @@
 #include <linux/device.h>
 #include <linux/pci.h>
 #include <linux/htirq.h>
+#include <linux/irqdomain.h>
 #include <asm/hw_irq.h>
 #include <asm/apic.h>
 #include <asm/hypertransport.h>
@@ -61,31 +62,30 @@ static struct irq_chip ht_irq_chip = {
 	.flags			= IRQCHIP_SKIP_SET_WAKE,
 };
 
+int arch_alloc_ht_irq(struct pci_dev *dev)
+{
+	return irq_domain_alloc_irqs(NULL, 1, dev_to_node(&dev->dev), NULL);
+}
+
+void arch_free_ht_irq(int irq)
+{
+	irq_domain_free_irqs(irq, 1);
+}
+
 int arch_setup_ht_irq(unsigned int irq, struct pci_dev *dev)
 {
 	struct irq_cfg *cfg;
 	struct ht_irq_msg msg;
-	unsigned dest;
-	int err;
 
 	if (disable_apic)
 		return -ENXIO;
 
 	cfg = irq_cfg(irq);
-	err = assign_irq_vector(irq, cfg, apic->target_cpus());
-	if (err)
-		return err;
-
-	err = apic->cpu_mask_to_apicid_and(cfg->domain,
-					   apic->target_cpus(), &dest);
-	if (err)
-		return err;
-
-	msg.address_hi = HT_IRQ_HIGH_DEST_ID(dest);
+	msg.address_hi = HT_IRQ_HIGH_DEST_ID(cfg->dest_apicid);
 
 	msg.address_lo =
 		HT_IRQ_LOW_BASE |
-		HT_IRQ_LOW_DEST_ID(dest) |
+		HT_IRQ_LOW_DEST_ID(cfg->dest_apicid) |
 		HT_IRQ_LOW_VECTOR(cfg->vector) |
 		((apic->irq_dest_mode == 0) ?
 			HT_IRQ_LOW_DM_PHYSICAL :