treewide: Use helper function to access irq_data->msi_desc

Use irq_data access helper to access irq_data->msi_desc, so we can
move msi_desc from struct irq_data into struct irq_common_data later.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/ia64/kernel/msi_ia64.c

@@ -23,7 +23,7 @@ static int ia64_set_msi_irq_affinity(struct irq_data *idata,
 	if (irq_prepare_move(irq, cpu))
 		return -1;
 
-	__get_cached_msi_msg(idata->msi_desc, &msg);
+	__get_cached_msi_msg(irq_data_get_msi_desc(idata), &msg);
 
 	addr = msg.address_lo;
 	addr &= MSI_ADDR_DEST_ID_MASK;

arch/ia64/sn/kernel/msi_sn.c

@@ -175,7 +175,7 @@ static int sn_set_msi_irq_affinity(struct irq_data *data,
 	 * Release XIO resources for the old MSI PCI address
 	 */
 
-	__get_cached_msi_msg(data->msi_desc, &msg);
+	__get_cached_msi_msg(irq_data_get_msi_desc(data), &msg);
 	sn_pdev = (struct pcidev_info *)sn_irq_info->irq_pciioinfo;
 	pdev = sn_pdev->pdi_linux_pcidev;
 	provider = SN_PCIDEV_BUSPROVIDER(pdev);

arch/powerpc/sysdev/xics/ics-opal.c

@@ -72,7 +72,7 @@ static unsigned int ics_opal_startup(struct irq_data *d)
 	 * card, using the MSI mask bits. Firmware doesn't appear to unmask
 	 * at that level, so we do it here by hand.
 	 */
-	if (d->msi_desc)
+	if (irq_data_get_msi_desc(d))
 		pci_msi_unmask_irq(d);
 #endif
 

arch/powerpc/sysdev/xics/ics-rtas.c

@@ -75,7 +75,7 @@ static unsigned int ics_rtas_startup(struct irq_data *d)
 	 * card, using the MSI mask bits. Firmware doesn't appear to unmask
 	 * at that level, so we do it here by hand.
 	 */
-	if (d->msi_desc)
+	if (irq_data_get_msi_desc(d))
 		pci_msi_unmask_irq(d);
 #endif
 	/* unmask it */

arch/tile/kernel/pci_gx.c

@@ -1442,7 +1442,7 @@ static struct pci_ops tile_cfg_ops = {
 /* MSI support starts here. */
 static unsigned int tilegx_msi_startup(struct irq_data *d)
 {
-	if (d->msi_desc)
+	if (irq_data_get_msi_desc(d))
 		pci_msi_unmask_irq(d);
 
 	return 0;

drivers/pci/msi.c

@@ -1145,7 +1145,7 @@ EXPORT_SYMBOL(pci_enable_msix_range);
  */
 void pci_msi_domain_write_msg(struct irq_data *irq_data, struct msi_msg *msg)
 {
-	struct msi_desc *desc = irq_data->msi_desc;
+	struct msi_desc *desc = irq_data_get_msi_desc(irq_data);
 
 	/*
 	 * For MSI-X desc->irq is always equal to irq_data->irq. For