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

Use new irqdomain interfaces to allocate/free IRQ for DMAR and interrupt
remapping, so we can remove GENERIC_IRQ_LEGACY_ALLOC_HWIRQ later.

The private definitions of irq_alloc_hwirqs()/irq_free_hwirqs() are a
temporary solution, they will be removed once we have converted the
interrupt remapping driver to use irqdomain framework.

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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: iommu@lists.linux-foundation.org
Cc: Joerg Roedel <jroedel@suse.de>
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>
Cc: Joerg Roedel <joro@8bytes.org>
Link: http://lkml.kernel.org/r/1428905519-23704-8-git-send-email-jiang.liu@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/include/asm/irq_remapping.h

@@ -99,7 +99,7 @@ static inline bool setup_remapped_irq(int irq,
 }
 #endif /* CONFIG_IRQ_REMAP */
 
-#define dmar_alloc_hwirq()	irq_alloc_hwirq(-1)
-#define dmar_free_hwirq		irq_free_hwirq
+extern int dmar_alloc_hwirq(void);
+extern void dmar_free_hwirq(int irq);
 
 #endif /* __X86_IRQ_REMAPPING_H */

arch/x86/kernel/apic/msi.c

@@ -223,6 +223,16 @@ int arch_setup_dmar_msi(unsigned int irq)
 				      "edge");
 	return 0;
 }
+
+int dmar_alloc_hwirq(void)
+{
+	return irq_domain_alloc_irqs(NULL, 1, NUMA_NO_NODE, NULL);
+}
+
+void dmar_free_hwirq(int irq)
+{
+	irq_domain_free_irqs(irq, 1);
+}
 #endif
 
 /*

drivers/iommu/irq_remapping.c

@@ -6,6 +6,7 @@
 #include <linux/msi.h>
 #include <linux/irq.h>
 #include <linux/pci.h>
+#include <linux/irqdomain.h>
 
 #include <asm/hw_irq.h>
 #include <asm/irq_remapping.h>
@@ -49,6 +50,18 @@ static void irq_remapping_disable_io_apic(void)
 		disconnect_bsp_APIC(0);
 }
 
+#ifndef CONFIG_GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
+static unsigned int irq_alloc_hwirqs(int cnt, int node)
+{
+	return irq_domain_alloc_irqs(NULL, -1, cnt, node, NULL);
+}
+
+static void irq_free_hwirqs(unsigned int from, int cnt)
+{
+	irq_domain_free_irqs(from, cnt);
+}
+#endif
+
 static int do_setup_msi_irqs(struct pci_dev *dev, int nvec)
 {
 	int ret, sub_handle, nvec_pow2, index = 0;
@@ -104,7 +117,7 @@ static int do_setup_msix_irqs(struct pci_dev *dev, int nvec)
 
 	list_for_each_entry(msidesc, &dev->msi_list, list) {
 
-		irq = irq_alloc_hwirq(node);
+		irq = irq_alloc_hwirqs(1, node);
 		if (irq == 0)
 			return -1;
 
@@ -127,7 +140,7 @@ static int do_setup_msix_irqs(struct pci_dev *dev, int nvec)
 	return 0;
 
 error:
-	irq_free_hwirq(irq);
+	irq_free_hwirqs(irq, 1);
 	return ret;
 }