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