alpha/PCI: Call iomem_is_exclusive() for IORESOURCE_MEM, but not IORESOURCE_IO

BugLink: https://bugs.launchpad.net/bugs/1878232

commit c20e1280 upstream.

The alpha pci_mmap_resource() is used for both IORESOURCE_MEM and
IORESOURCE_IO resources, but iomem_is_exclusive() is only applicable for
IORESOURCE_MEM.

Call iomem_is_exclusive() only for IORESOURCE_MEM resources, and do it
earlier to match the generic version of pci_mmap_resource().

Fixes: 10a0ef39 ("PCI/alpha: pci sysfs resources")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ian May <ian.may@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

arch/alpha/kernel/pci-sysfs.c

@@ -77,10 +77,10 @@ static int pci_mmap_resource(struct kobject *kobj,
 	if (i >= PCI_ROM_RESOURCE)
 		return -ENODEV;
 
-	if (!__pci_mmap_fits(pdev, i, vma, sparse))
+	if (res->flags & IORESOURCE_MEM && iomem_is_exclusive(res->start))
 		return -EINVAL;
 
-	if (iomem_is_exclusive(res->start))
+	if (!__pci_mmap_fits(pdev, i, vma, sparse))
 		return -EINVAL;
 
 	pcibios_resource_to_bus(pdev->bus, &bar, res);