x86/PCI: Expand the x86_msi_ops to have a restore MSIs.

The MSI restore function will become a function pointer in an
x86_msi_ops struct. It defaults to the implementation in the
io_apic.c and msi.c. We piggyback on the indirection mechanism
introduced by "x86: Introduce x86_msi_ops".

Cc: x86@kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: linux-pci@vger.kernel.org
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/arch/x86/include/asm/pci.h b/arch/x86/include/asm/pci.h
index d498943..df75d07 100644
--- a/arch/x86/include/asm/pci.h
+++ b/arch/x86/include/asm/pci.h
@@ -112,19 +112,28 @@
 {
 	x86_msi.teardown_msi_irq(irq);
 }
+static inline void x86_restore_msi_irqs(struct pci_dev *dev, int irq)
+{
+	x86_msi.restore_msi_irqs(dev, irq);
+}
 #define arch_setup_msi_irqs x86_setup_msi_irqs
 #define arch_teardown_msi_irqs x86_teardown_msi_irqs
 #define arch_teardown_msi_irq x86_teardown_msi_irq
+#define arch_restore_msi_irqs x86_restore_msi_irqs
 /* implemented in arch/x86/kernel/apic/io_apic. */
 int native_setup_msi_irqs(struct pci_dev *dev, int nvec, int type);
 void native_teardown_msi_irq(unsigned int irq);
+void native_restore_msi_irqs(struct pci_dev *dev, int irq);
 /* default to the implementation in drivers/lib/msi.c */
 #define HAVE_DEFAULT_MSI_TEARDOWN_IRQS
+#define HAVE_DEFAULT_MSI_RESTORE_IRQS
 void default_teardown_msi_irqs(struct pci_dev *dev);
+void default_restore_msi_irqs(struct pci_dev *dev, int irq);
 #else
 #define native_setup_msi_irqs		NULL
 #define native_teardown_msi_irq		NULL
 #define default_teardown_msi_irqs	NULL
+#define default_restore_msi_irqs	NULL
 #endif
 
 #define PCI_DMA_BUS_IS_PHYS (dma_ops->is_phys)