v4.19.13 snapshot.
diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c
new file mode 100644
index 0000000..e9c6b12
--- /dev/null
+++ b/drivers/pci/remove.c
@@ -0,0 +1,165 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/pci.h>
+#include <linux/module.h>
+#include "pci.h"
+
+static void pci_free_resources(struct pci_dev *dev)
+{
+ int i;
+
+ for (i = 0; i < PCI_NUM_RESOURCES; i++) {
+ struct resource *res = dev->resource + i;
+ if (res->parent)
+ release_resource(res);
+ }
+}
+
+static void pci_stop_dev(struct pci_dev *dev)
+{
+ pci_pme_active(dev, false);
+
+ if (pci_dev_is_added(dev)) {
+ device_release_driver(&dev->dev);
+ pci_proc_detach_device(dev);
+ pci_remove_sysfs_dev_files(dev);
+
+ pci_dev_assign_added(dev, false);
+ }
+}
+
+static void pci_destroy_dev(struct pci_dev *dev)
+{
+ if (!dev->dev.kobj.parent)
+ return;
+
+ device_del(&dev->dev);
+
+ down_write(&pci_bus_sem);
+ list_del(&dev->bus_list);
+ up_write(&pci_bus_sem);
+
+ pcie_aspm_exit_link_state(dev);
+ pci_bridge_d3_update(dev);
+ pci_free_resources(dev);
+ put_device(&dev->dev);
+}
+
+void pci_remove_bus(struct pci_bus *bus)
+{
+ pci_proc_detach_bus(bus);
+
+ down_write(&pci_bus_sem);
+ list_del(&bus->node);
+ pci_bus_release_busn_res(bus);
+ up_write(&pci_bus_sem);
+ pci_remove_legacy_files(bus);
+
+ if (bus->ops->remove_bus)
+ bus->ops->remove_bus(bus);
+
+ pcibios_remove_bus(bus);
+ device_unregister(&bus->dev);
+}
+EXPORT_SYMBOL(pci_remove_bus);
+
+static void pci_stop_bus_device(struct pci_dev *dev)
+{
+ struct pci_bus *bus = dev->subordinate;
+ struct pci_dev *child, *tmp;
+
+ /*
+ * Stopping an SR-IOV PF device removes all the associated VFs,
+ * which will update the bus->devices list and confuse the
+ * iterator. Therefore, iterate in reverse so we remove the VFs
+ * first, then the PF.
+ */
+ if (bus) {
+ list_for_each_entry_safe_reverse(child, tmp,
+ &bus->devices, bus_list)
+ pci_stop_bus_device(child);
+ }
+
+ pci_stop_dev(dev);
+}
+
+static void pci_remove_bus_device(struct pci_dev *dev)
+{
+ struct pci_bus *bus = dev->subordinate;
+ struct pci_dev *child, *tmp;
+
+ if (bus) {
+ list_for_each_entry_safe(child, tmp,
+ &bus->devices, bus_list)
+ pci_remove_bus_device(child);
+
+ pci_remove_bus(bus);
+ dev->subordinate = NULL;
+ }
+
+ pci_destroy_dev(dev);
+}
+
+/**
+ * pci_stop_and_remove_bus_device - remove a PCI device and any children
+ * @dev: the device to remove
+ *
+ * Remove a PCI device from the device lists, informing the drivers
+ * that the device has been removed. We also remove any subordinate
+ * buses and children in a depth-first manner.
+ *
+ * For each device we remove, delete the device structure from the
+ * device lists, remove the /proc entry, and notify userspace
+ * (/sbin/hotplug).
+ */
+void pci_stop_and_remove_bus_device(struct pci_dev *dev)
+{
+ pci_stop_bus_device(dev);
+ pci_remove_bus_device(dev);
+}
+EXPORT_SYMBOL(pci_stop_and_remove_bus_device);
+
+void pci_stop_and_remove_bus_device_locked(struct pci_dev *dev)
+{
+ pci_lock_rescan_remove();
+ pci_stop_and_remove_bus_device(dev);
+ pci_unlock_rescan_remove();
+}
+EXPORT_SYMBOL_GPL(pci_stop_and_remove_bus_device_locked);
+
+void pci_stop_root_bus(struct pci_bus *bus)
+{
+ struct pci_dev *child, *tmp;
+ struct pci_host_bridge *host_bridge;
+
+ if (!pci_is_root_bus(bus))
+ return;
+
+ host_bridge = to_pci_host_bridge(bus->bridge);
+ list_for_each_entry_safe_reverse(child, tmp,
+ &bus->devices, bus_list)
+ pci_stop_bus_device(child);
+
+ /* stop the host bridge */
+ device_release_driver(&host_bridge->dev);
+}
+EXPORT_SYMBOL_GPL(pci_stop_root_bus);
+
+void pci_remove_root_bus(struct pci_bus *bus)
+{
+ struct pci_dev *child, *tmp;
+ struct pci_host_bridge *host_bridge;
+
+ if (!pci_is_root_bus(bus))
+ return;
+
+ host_bridge = to_pci_host_bridge(bus->bridge);
+ list_for_each_entry_safe(child, tmp,
+ &bus->devices, bus_list)
+ pci_remove_bus_device(child);
+ pci_remove_bus(bus);
+ host_bridge->bus = NULL;
+
+ /* remove the host bridge */
+ device_unregister(&host_bridge->dev);
+}
+EXPORT_SYMBOL_GPL(pci_remove_root_bus);