drivers/pci/remove.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/pci.h>
   3 #include <linux/module.h>
   4 #include "pci.h"
   5
   6 static void pci_free_resources(struct pci_dev *dev)
   7 {
   8         int i;
   9
  10         for (i = 0; i < PCI_NUM_RESOURCES; i++) {
  11                 struct resource *res = dev->resource + i;
  12                 if (res->parent)
  13                         release_resource(res);
  14         }
  15 }
  16
  17 static void pci_stop_dev(struct pci_dev *dev)
  18 {
  19         pci_pme_active(dev, false);
  20
  21         if (pci_dev_is_added(dev)) {
  22
  23                 device_release_driver(&dev->dev);
  24                 pci_proc_detach_device(dev);
  25                 pci_remove_sysfs_dev_files(dev);
  26
  27                 pci_dev_assign_added(dev, false);
  28         }
  29 }
  30
  31 static void pci_destroy_dev(struct pci_dev *dev)
  32 {
  33         if (!dev->dev.kobj.parent)
  34                 return;
  35
  36         device_del(&dev->dev);
  37
  38         down_write(&pci_bus_sem);
  39         list_del(&dev->bus_list);
  40         up_write(&pci_bus_sem);
  41
  42         pcie_aspm_exit_link_state(dev);
  43         pci_bridge_d3_update(dev);
  44         pci_free_resources(dev);
  45         put_device(&dev->dev);
  46 }
  47
  48 void pci_remove_bus(struct pci_bus *bus)
  49 {
  50         pci_proc_detach_bus(bus);
  51
  52         down_write(&pci_bus_sem);
  53         list_del(&bus->node);
  54         pci_bus_release_busn_res(bus);
  55         up_write(&pci_bus_sem);
  56         pci_remove_legacy_files(bus);
  57
  58         if (bus->ops->remove_bus)
  59                 bus->ops->remove_bus(bus);
  60
  61         pcibios_remove_bus(bus);
  62         device_unregister(&bus->dev);
  63 }
  64 EXPORT_SYMBOL(pci_remove_bus);
  65
  66 static void pci_stop_bus_device(struct pci_dev *dev)
  67 {
  68         struct pci_bus *bus = dev->subordinate;
  69         struct pci_dev *child, *tmp;
  70
  71         /*
  72          * Stopping an SR-IOV PF device removes all the associated VFs,
  73          * which will update the bus->devices list and confuse the
  74          * iterator.  Therefore, iterate in reverse so we remove the VFs
  75          * first, then the PF.
  76          */
  77         if (bus) {
  78                 list_for_each_entry_safe_reverse(child, tmp,
  79                                                  &bus->devices, bus_list)
  80                         pci_stop_bus_device(child);
  81         }
  82
  83         pci_stop_dev(dev);
  84 }
  85
  86 static void pci_remove_bus_device(struct pci_dev *dev)
  87 {
  88         struct pci_bus *bus = dev->subordinate;
  89         struct pci_dev *child, *tmp;
  90
  91         if (bus) {
  92                 list_for_each_entry_safe(child, tmp,
  93                                          &bus->devices, bus_list)
  94                         pci_remove_bus_device(child);
  95
  96                 pci_remove_bus(bus);
  97                 dev->subordinate = NULL;
  98         }
  99
 100         pci_destroy_dev(dev);
 101 }
 102
 103 /**
 104  * pci_stop_and_remove_bus_device - remove a PCI device and any children
 105  * @dev: the device to remove
 106  *
 107  * Remove a PCI device from the device lists, informing the drivers
 108  * that the device has been removed.  We also remove any subordinate
 109  * buses and children in a depth-first manner.
 110  *
 111  * For each device we remove, delete the device structure from the
 112  * device lists, remove the /proc entry, and notify userspace
 113  * (/sbin/hotplug).
 114  */
 115 void pci_stop_and_remove_bus_device(struct pci_dev *dev)
 116 {
 117         pci_stop_bus_device(dev);
 118         pci_remove_bus_device(dev);
 119 }
 120 EXPORT_SYMBOL(pci_stop_and_remove_bus_device);
 121
 122 void pci_stop_and_remove_bus_device_locked(struct pci_dev *dev)
 123 {
 124         pci_lock_rescan_remove();
 125         pci_stop_and_remove_bus_device(dev);
 126         pci_unlock_rescan_remove();
 127 }
 128 EXPORT_SYMBOL_GPL(pci_stop_and_remove_bus_device_locked);
 129
 130 void pci_stop_root_bus(struct pci_bus *bus)
 131 {
 132         struct pci_dev *child, *tmp;
 133         struct pci_host_bridge *host_bridge;
 134
 135         if (!pci_is_root_bus(bus))
 136                 return;
 137
 138         host_bridge = to_pci_host_bridge(bus->bridge);
 139         list_for_each_entry_safe_reverse(child, tmp,
 140                                          &bus->devices, bus_list)
 141                 pci_stop_bus_device(child);
 142
 143         /* stop the host bridge */
 144         device_release_driver(&host_bridge->dev);
 145 }
 146 EXPORT_SYMBOL_GPL(pci_stop_root_bus);
 147
 148 void pci_remove_root_bus(struct pci_bus *bus)
 149 {
 150         struct pci_dev *child, *tmp;
 151         struct pci_host_bridge *host_bridge;
 152
 153         if (!pci_is_root_bus(bus))
 154                 return;
 155
 156         host_bridge = to_pci_host_bridge(bus->bridge);
 157         list_for_each_entry_safe(child, tmp,
 158                                  &bus->devices, bus_list)
 159                 pci_remove_bus_device(child);
 160         pci_remove_bus(bus);
 161         host_bridge->bus = NULL;
 162
 163         /* remove the host bridge */
 164         device_del(&host_bridge->dev);
 165 }
 166 EXPORT_SYMBOL_GPL(pci_remove_root_bus);