PCI: sgihp: Iterate over all devices in slot, not functions 0-7

Iterate through devices in a slot by using the upstream bridge's
"bus->devices" list instead of assuming they are functions 0-7.  It's
possible there are several slots on the same pci_bus, so restrict it to
only devices matching this slot's device number.

ARI (which allows functions 0-255) is a PCIe-only feature, and this is
a PCI hotplug driver, so we shouldn't find anything other than functions
0-7, but it's better to iterate the same way as other hotplug drivers.

[bhelgaas: changelog, check PCI_SLOT, fix disable_slot()]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/hotplug/sgi_hotplug.c

@@ -334,7 +334,7 @@ static int enable_slot(struct hotplug_slot *bss_hotplug_slot)
 	struct slot *slot = bss_hotplug_slot->private;
 	struct pci_bus *new_bus = NULL;
 	struct pci_dev *dev;
-	int func, num_funcs;
+	int num_funcs;
 	int new_ppb = 0;
 	int rc;
 	char *ssdt = NULL;
@@ -381,29 +381,26 @@ static int enable_slot(struct hotplug_slot *bss_hotplug_slot)
 	 * to the Linux PCI interface and tell the drivers
 	 * about them.
 	 */
-	for (func = 0; func < num_funcs;  func++) {
-		dev = pci_get_slot(slot->pci_bus,
-				   PCI_DEVFN(slot->device_num + 1,
-					     PCI_FUNC(func)));
-		if (dev) {
-			/* Need to do slot fixup on PPB before fixup of children
-			 * (PPB's pcidev_info needs to be in pcidev_info list
-			 * before child's SN_PCIDEV_INFO() call to setup
-			 * pdi_host_pcidev_info).
-			 */
-			pcibios_fixup_device_resources(dev);
-			if (SN_ACPI_BASE_SUPPORT())
-				sn_acpi_slot_fixup(dev);
-			else
-				sn_io_slot_fixup(dev);
-			if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
-				pci_hp_add_bridge(dev);
-				if (dev->subordinate) {
-					new_bus = dev->subordinate;
-					new_ppb = 1;
-				}
+	list_for_each_entry(dev, &slot->pci_bus->devices, bus_list) {
+		if (PCI_SLOT(dev->devfn) != slot->device_num + 1)
+			continue;
+
+		/* Need to do slot fixup on PPB before fixup of children
+		 * (PPB's pcidev_info needs to be in pcidev_info list
+		 * before child's SN_PCIDEV_INFO() call to setup
+		 * pdi_host_pcidev_info).
+		 */
+		pcibios_fixup_device_resources(dev);
+		if (SN_ACPI_BASE_SUPPORT())
+			sn_acpi_slot_fixup(dev);
+		else
+			sn_io_slot_fixup(dev);
+		if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
+			pci_hp_add_bridge(dev);
+			if (dev->subordinate) {
+				new_bus = dev->subordinate;
+				new_ppb = 1;
 			}
-			pci_dev_put(dev);
 		}
 	}
 
@@ -485,8 +482,7 @@ static int enable_slot(struct hotplug_slot *bss_hotplug_slot)
 static int disable_slot(struct hotplug_slot *bss_hotplug_slot)
 {
 	struct slot *slot = bss_hotplug_slot->private;
-	struct pci_dev *dev;
-	int func;
+	struct pci_dev *dev, *temp;
 	int rc;
 	acpi_owner_id ssdt_id = 0;
 
@@ -546,15 +542,14 @@ static int disable_slot(struct hotplug_slot *bss_hotplug_slot)
 	}
 
 	/* Free the SN resources assigned to the Linux device.*/
-	for (func = 0; func < 8;  func++) {
-		dev = pci_get_slot(slot->pci_bus,
-				   PCI_DEVFN(slot->device_num + 1,
-				   	     PCI_FUNC(func)));
-		if (dev) {
-			sn_bus_free_data(dev);
-			pci_stop_and_remove_bus_device(dev);
-			pci_dev_put(dev);
-		}
+	list_for_each_entry_safe(dev, temp, &slot->pci_bus->devices, bus_list) {
+		if (PCI_SLOT(dev->devfn) != slot->device_num + 1)
+			continue;
+
+		pci_dev_get(dev);
+		sn_bus_free_data(dev);
+		pci_stop_and_remove_bus_device(dev);
+		pci_dev_put(dev);
 	}
 
 	/* Remove the SSDT for the slot from the ACPI namespace */