drivers/pci/remove.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/pci.h>
   3 #include <linux/module.h>
   4 #include <linux/of.h>
   5 #include <linux/of_platform.h>
   6 #include <linux/platform_device.h>
   7
   8 #include "pci.h"
   9
  10 static void pci_free_resources(struct pci_dev *dev)
  11 {
  12         struct resource *res;
  13
  14         pci_dev_for_each_resource(dev, res) {
  15                 if (res->parent)
  16                         release_resource(res);
  17         }
  18 }
  19
  20 static void pci_pwrctrl_unregister(struct device *dev)
  21 {
  22         struct platform_device *pdev;
  23
  24         pdev = of_find_device_by_node(dev_of_node(dev));
  25         if (!pdev)
  26                 return;
  27
  28         of_device_unregister(pdev);
  29         of_node_clear_flag(dev_of_node(dev), OF_POPULATED);
  30 }
  31
  32 static void pci_stop_dev(struct pci_dev *dev)
  33 {
  34         pci_pme_active(dev, false);
  35
  36         if (!pci_dev_test_and_clear_added(dev))
  37                 return;
  38
  39         pci_pwrctrl_unregister(&dev->dev);
  40         device_release_driver(&dev->dev);
  41         pci_proc_detach_device(dev);
  42         pci_remove_sysfs_dev_files(dev);
  43         of_pci_remove_node(dev);
  44 }
  45
  46 static void pci_destroy_dev(struct pci_dev *dev)
  47 {
  48         if (pci_dev_test_and_set_removed(dev))
  49                 return;
  50
  51         pci_npem_remove(dev);
  52
  53         device_del(&dev->dev);
  54
  55         down_write(&pci_bus_sem);
  56         list_del(&dev->bus_list);
  57         up_write(&pci_bus_sem);
  58
  59         pci_doe_destroy(dev);
  60         pcie_aspm_exit_link_state(dev);
  61         pci_bridge_d3_update(dev);
  62         pci_free_resources(dev);
  63         put_device(&dev->dev);
  64 }
  65
  66 void pci_remove_bus(struct pci_bus *bus)
  67 {
  68         pci_proc_detach_bus(bus);
  69
  70         down_write(&pci_bus_sem);
  71         list_del(&bus->node);
  72         pci_bus_release_busn_res(bus);
  73         up_write(&pci_bus_sem);
  74         pci_remove_legacy_files(bus);
  75
  76         if (bus->ops->remove_bus)
  77                 bus->ops->remove_bus(bus);
  78
  79         pcibios_remove_bus(bus);
  80         device_unregister(&bus->dev);
  81 }
  82 EXPORT_SYMBOL(pci_remove_bus);
  83
  84 static void pci_stop_bus_device(struct pci_dev *dev)
  85 {
  86         struct pci_bus *bus = dev->subordinate;
  87         struct pci_dev *child, *tmp;
  88
  89         /*
  90          * Stopping an SR-IOV PF device removes all the associated VFs,
  91          * which will update the bus->devices list and confuse the
  92          * iterator.  Therefore, iterate in reverse so we remove the VFs
  93          * first, then the PF.
  94          */
  95         if (bus) {
  96                 list_for_each_entry_safe_reverse(child, tmp,
  97                                                  &bus->devices, bus_list)
  98                         pci_stop_bus_device(child);
  99         }
 100
 101         pci_stop_dev(dev);
 102 }
 103
 104 static void pci_remove_bus_device(struct pci_dev *dev)
 105 {
 106         struct pci_bus *bus = dev->subordinate;
 107         struct pci_dev *child, *tmp;
 108
 109         if (bus) {
 110                 list_for_each_entry_safe(child, tmp,
 111                                          &bus->devices, bus_list)
 112                         pci_remove_bus_device(child);
 113
 114                 pci_remove_bus(bus);
 115                 dev->subordinate = NULL;
 116         }
 117
 118         pci_destroy_dev(dev);
 119 }
 120
 121 /**
 122  * pci_stop_and_remove_bus_device - remove a PCI device and any children
 123  * @dev: the device to remove
 124  *
 125  * Remove a PCI device from the device lists, informing the drivers
 126  * that the device has been removed.  We also remove any subordinate
 127  * buses and children in a depth-first manner.
 128  *
 129  * For each device we remove, delete the device structure from the
 130  * device lists, remove the /proc entry, and notify userspace
 131  * (/sbin/hotplug).
 132  */
 133 void pci_stop_and_remove_bus_device(struct pci_dev *dev)
 134 {
 135         pci_stop_bus_device(dev);
 136         pci_remove_bus_device(dev);
 137 }
 138 EXPORT_SYMBOL(pci_stop_and_remove_bus_device);
 139
 140 void pci_stop_and_remove_bus_device_locked(struct pci_dev *dev)
 141 {
 142         pci_lock_rescan_remove();
 143         pci_stop_and_remove_bus_device(dev);
 144         pci_unlock_rescan_remove();
 145 }
 146 EXPORT_SYMBOL_GPL(pci_stop_and_remove_bus_device_locked);
 147
 148 void pci_stop_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_reverse(child, tmp,
 158                                          &bus->devices, bus_list)
 159                 pci_stop_bus_device(child);
 160
 161         /* stop the host bridge */
 162         device_release_driver(&host_bridge->dev);
 163 }
 164 EXPORT_SYMBOL_GPL(pci_stop_root_bus);
 165
 166 void pci_remove_root_bus(struct pci_bus *bus)
 167 {
 168         struct pci_dev *child, *tmp;
 169         struct pci_host_bridge *host_bridge;
 170
 171         if (!pci_is_root_bus(bus))
 172                 return;
 173
 174         host_bridge = to_pci_host_bridge(bus->bridge);
 175         list_for_each_entry_safe(child, tmp,
 176                                  &bus->devices, bus_list)
 177                 pci_remove_bus_device(child);
 178
 179 #ifdef CONFIG_PCI_DOMAINS_GENERIC
 180         /* Release domain_nr if it was dynamically allocated */
 181         if (host_bridge->domain_nr == PCI_DOMAIN_NR_NOT_SET)
 182                 pci_bus_release_domain_nr(host_bridge->dev.parent, bus->domain_nr);
 183 #endif
 184
 185         pci_remove_bus(bus);
 186         host_bridge->bus = NULL;
 187
 188         /* remove the host bridge */
 189         device_del(&host_bridge->dev);
 190 }
 191 EXPORT_SYMBOL_GPL(pci_remove_root_bus);