drivers/pci/remove.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/pci.h>
   3 #include <linux/module.h>
   4 #include <linux/pci-aspm.h>
   5 #include "pci.h"
   6
   7 static void pci_free_resources(struct pci_dev *dev)
   8 {
   9         int i;
  10
  11         for (i = 0; i < PCI_NUM_RESOURCES; i++) {
  12                 struct resource *res = dev->resource + i;
  13                 if (res->parent)
  14                         release_resource(res);
  15         }
  16 }
  17
  18 static void pci_stop_dev(struct pci_dev *dev)
  19 {
  20         pci_pme_active(dev, false);
  21
  22         if (pci_dev_is_added(dev)) {
  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         if (dev->bus->self)
  31                 pcie_aspm_exit_link_state(dev);
  32 }
  33
  34 static void pci_destroy_dev(struct pci_dev *dev)
  35 {
  36         if (!dev->dev.kobj.parent)
  37                 return;
  38
  39         device_del(&dev->dev);
  40
  41         down_write(&pci_bus_sem);
  42         list_del(&dev->bus_list);
  43         up_write(&pci_bus_sem);
  44
  45         pci_bridge_d3_update(dev);
  46         pci_free_resources(dev);
  47         put_device(&dev->dev);
  48 }
  49
  50 void pci_remove_bus(struct pci_bus *bus)
  51 {
  52         pci_proc_detach_bus(bus);
  53
  54         down_write(&pci_bus_sem);
  55         list_del(&bus->node);
  56         pci_bus_release_busn_res(bus);
  57         up_write(&pci_bus_sem);
  58         pci_remove_legacy_files(bus);
  59
  60         if (bus->ops->remove_bus)
  61                 bus->ops->remove_bus(bus);
  62
  63         pcibios_remove_bus(bus);
  64         device_unregister(&bus->dev);
  65 }
  66 EXPORT_SYMBOL(pci_remove_bus);
  67
  68 static void pci_stop_bus_device(struct pci_dev *dev)
  69 {
  70         struct pci_bus *bus = dev->subordinate;
  71         struct pci_dev *child, *tmp;
  72
  73         /*
  74          * Stopping an SR-IOV PF device removes all the associated VFs,
  75          * which will update the bus->devices list and confuse the
  76          * iterator.  Therefore, iterate in reverse so we remove the VFs
  77          * first, then the PF.
  78          */
  79         if (bus) {
  80                 list_for_each_entry_safe_reverse(child, tmp,
  81                                                  &bus->devices, bus_list)
  82                         pci_stop_bus_device(child);
  83         }
  84
  85         pci_stop_dev(dev);
  86 }
  87
  88 static void pci_remove_bus_device(struct pci_dev *dev)
  89 {
  90         struct pci_bus *bus = dev->subordinate;
  91         struct pci_dev *child, *tmp;
  92
  93         if (bus) {
  94                 list_for_each_entry_safe(child, tmp,
  95                                          &bus->devices, bus_list)
  96                         pci_remove_bus_device(child);
  97
  98                 pci_remove_bus(bus);
  99                 dev->subordinate = NULL;
 100         }
 101
 102         pci_destroy_dev(dev);
 103 }
 104
 105 /**
 106  * pci_stop_and_remove_bus_device - remove a PCI device and any children
 107  * @dev: the device to remove
 108  *
 109  * Remove a PCI device from the device lists, informing the drivers
 110  * that the device has been removed.  We also remove any subordinate
 111  * buses and children in a depth-first manner.
 112  *
 113  * For each device we remove, delete the device structure from the
 114  * device lists, remove the /proc entry, and notify userspace
 115  * (/sbin/hotplug).
 116  */
 117 void pci_stop_and_remove_bus_device(struct pci_dev *dev)
 118 {
 119         pci_stop_bus_device(dev);
 120         pci_remove_bus_device(dev);
 121 }
 122 EXPORT_SYMBOL(pci_stop_and_remove_bus_device);
 123
 124 void pci_stop_and_remove_bus_device_locked(struct pci_dev *dev)
 125 {
 126         pci_lock_rescan_remove();
 127         pci_stop_and_remove_bus_device(dev);
 128         pci_unlock_rescan_remove();
 129 }
 130 EXPORT_SYMBOL_GPL(pci_stop_and_remove_bus_device_locked);
 131
 132 void pci_stop_root_bus(struct pci_bus *bus)
 133 {
 134         struct pci_dev *child, *tmp;
 135         struct pci_host_bridge *host_bridge;
 136
 137         if (!pci_is_root_bus(bus))
 138                 return;
 139
 140         host_bridge = to_pci_host_bridge(bus->bridge);
 141         list_for_each_entry_safe_reverse(child, tmp,
 142                                          &bus->devices, bus_list)
 143                 pci_stop_bus_device(child);
 144
 145         /* stop the host bridge */
 146         device_release_driver(&host_bridge->dev);
 147 }
 148 EXPORT_SYMBOL_GPL(pci_stop_root_bus);
 149
 150 void pci_remove_root_bus(struct pci_bus *bus)
 151 {
 152         struct pci_dev *child, *tmp;
 153         struct pci_host_bridge *host_bridge;
 154
 155         if (!pci_is_root_bus(bus))
 156                 return;
 157
 158         host_bridge = to_pci_host_bridge(bus->bridge);
 159         list_for_each_entry_safe(child, tmp,
 160                                  &bus->devices, bus_list)
 161                 pci_remove_bus_device(child);
 162         pci_remove_bus(bus);
 163         host_bridge->bus = NULL;
 164
 165         /* remove the host bridge */
 166         device_unregister(&host_bridge->dev);
 167 }
 168 EXPORT_SYMBOL_GPL(pci_remove_root_bus);