PCI: Make pci_rescan_bus handle add_list

This allows us to allocate resources to hotplug bridges during
remove/rescan.

We need to move the function to setup-bus.c so it can use
__pci_bus_size_bridges and __pci_bus_assign_resources directly to take
the add_list resource tracking list.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 39 insertions, 0 deletions

diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 97c1eda96e64..c09c67ab5612 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -1357,3 +1357,42 @@ enable_all:
 	pci_enable_bridges(parent);
 }
 EXPORT_SYMBOL_GPL(pci_assign_unassigned_bridge_resources);
+
+#ifdef CONFIG_HOTPLUG
+/**
+ * pci_rescan_bus - scan a PCI bus for devices.
+ * @bus: PCI bus to scan
+ *
+ * Scan a PCI bus and child buses for new devices, adds them,
+ * and enables them.
+ *
+ * Returns the max number of subordinate bus discovered.
+ */
+unsigned int __ref pci_rescan_bus(struct pci_bus *bus)
+{
+	unsigned int max;
+	struct pci_dev *dev;
+	struct resource_list_x add_list; /* list of resources that
+					want additional resources */
+
+	max = pci_scan_child_bus(bus);
+
+	add_list.next = NULL;
+	down_read(&pci_bus_sem);
+	list_for_each_entry(dev, &bus->devices, bus_list)
+		if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
+		    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
+			if (dev->subordinate)
+				__pci_bus_size_bridges(dev->subordinate,
+							 &add_list);
+	up_read(&pci_bus_sem);
+	__pci_bus_assign_resources(bus, &add_list, NULL);
+	BUG_ON(add_list.next);
+
+	pci_enable_bridges(bus);
+	pci_bus_add_devices(bus);
+
+	return max;
+}
+EXPORT_SYMBOL_GPL(pci_rescan_bus);
+#endif