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 int pci_pwrctl_unregister(struct device *dev, void *data)
  21 {
  22         struct device_node *pci_node = data, *plat_node = dev_of_node(dev);
  23
  24         if (dev_is_platform(dev) && plat_node && plat_node == pci_node) {
  25                 of_device_unregister(to_platform_device(dev));
  26                 of_node_clear_flag(plat_node, OF_POPULATED);
  27         }
  28
  29         return 0;
  30 }
  31
  32 static void pci_stop_dev(struct pci_dev *dev)
  33 {
  34         pci_pme_active(dev, false);
  35
  36         if (pci_dev_is_added(dev)) {
  37                 device_for_each_child(dev->dev.parent, dev_of_node(&dev->dev),
  38                                       pci_pwrctl_unregister);
  39                 device_release_driver(&dev->dev);
  40                 pci_proc_detach_device(dev);
  41                 pci_remove_sysfs_dev_files(dev);
  42                 of_pci_remove_node(dev);
  43
  44                 pci_dev_assign_added(dev, false);
  45         }
  46 }
  47
  48 static void pci_destroy_dev(struct pci_dev *dev)
  49 {
  50         if (!dev->dev.kobj.parent)
  51                 return;
  52
  53         pci_npem_remove(dev);
  54
  55         device_del(&dev->dev);
  56
  57         down_write(&pci_bus_sem);
  58         list_del(&dev->bus_list);
  59         up_write(&pci_bus_sem);
  60
  61         pci_doe_destroy(dev);
  62         pcie_aspm_exit_link_state(dev);
  63         pci_bridge_d3_update(dev);
  64         pci_free_resources(dev);
  65         put_device(&dev->dev);
  66 }
  67
  68 void pci_remove_bus(struct pci_bus *bus)
  69 {
  70         pci_proc_detach_bus(bus);
  71
  72         down_write(&pci_bus_sem);
  73         list_del(&bus->node);
  74         pci_bus_release_busn_res(bus);
  75         up_write(&pci_bus_sem);
  76         pci_remove_legacy_files(bus);
  77
  78         if (bus->ops->remove_bus)
  79                 bus->ops->remove_bus(bus);
  80
  81         pcibios_remove_bus(bus);
  82         device_unregister(&bus->dev);
  83 }
  84 EXPORT_SYMBOL(pci_remove_bus);
  85
  86 static void pci_stop_bus_device(struct pci_dev *dev)
  87 {
  88         struct pci_bus *bus = dev->subordinate;
  89         struct pci_dev *child, *tmp;
  90
  91         /*
  92          * Stopping an SR-IOV PF device removes all the associated VFs,
  93          * which will update the bus->devices list and confuse the
  94          * iterator.  Therefore, iterate in reverse so we remove the VFs
  95          * first, then the PF.
  96          */
  97         if (bus) {
  98                 list_for_each_entry_safe_reverse(child, tmp,
  99                                                  &bus->devices, bus_list)
 100                         pci_stop_bus_device(child);
 101         }
 102
 103         pci_stop_dev(dev);
 104 }
 105
 106 static void pci_remove_bus_device(struct pci_dev *dev)
 107 {
 108         struct pci_bus *bus = dev->subordinate;
 109         struct pci_dev *child, *tmp;
 110
 111         if (bus) {
 112                 list_for_each_entry_safe(child, tmp,
 113                                          &bus->devices, bus_list)
 114                         pci_remove_bus_device(child);
 115
 116                 pci_remove_bus(bus);
 117                 dev->subordinate = NULL;
 118         }
 119
 120         pci_destroy_dev(dev);
 121 }
 122
 123 /**
 124  * pci_stop_and_remove_bus_device - remove a PCI device and any children
 125  * @dev: the device to remove
 126  *
 127  * Remove a PCI device from the device lists, informing the drivers
 128  * that the device has been removed.  We also remove any subordinate
 129  * buses and children in a depth-first manner.
 130  *
 131  * For each device we remove, delete the device structure from the
 132  * device lists, remove the /proc entry, and notify userspace
 133  * (/sbin/hotplug).
 134  */
 135 void pci_stop_and_remove_bus_device(struct pci_dev *dev)
 136 {
 137         pci_stop_bus_device(dev);
 138         pci_remove_bus_device(dev);
 139 }
 140 EXPORT_SYMBOL(pci_stop_and_remove_bus_device);
 141
 142 void pci_stop_and_remove_bus_device_locked(struct pci_dev *dev)
 143 {
 144         pci_lock_rescan_remove();
 145         pci_stop_and_remove_bus_device(dev);
 146         pci_unlock_rescan_remove();
 147 }
 148 EXPORT_SYMBOL_GPL(pci_stop_and_remove_bus_device_locked);
 149
 150 void pci_stop_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_reverse(child, tmp,
 160                                          &bus->devices, bus_list)
 161                 pci_stop_bus_device(child);
 162
 163         /* stop the host bridge */
 164         device_release_driver(&host_bridge->dev);
 165 }
 166 EXPORT_SYMBOL_GPL(pci_stop_root_bus);
 167
 168 void pci_remove_root_bus(struct pci_bus *bus)
 169 {
 170         struct pci_dev *child, *tmp;
 171         struct pci_host_bridge *host_bridge;
 172
 173         if (!pci_is_root_bus(bus))
 174                 return;
 175
 176         host_bridge = to_pci_host_bridge(bus->bridge);
 177         list_for_each_entry_safe(child, tmp,
 178                                  &bus->devices, bus_list)
 179                 pci_remove_bus_device(child);
 180
 181 #ifdef CONFIG_PCI_DOMAINS_GENERIC
 182         /* Release domain_nr if it was dynamically allocated */
 183         if (host_bridge->domain_nr == PCI_DOMAIN_NR_NOT_SET)
 184                 pci_bus_release_domain_nr(host_bridge->dev.parent, bus->domain_nr);
 185 #endif
 186
 187         pci_remove_bus(bus);
 188         host_bridge->bus = NULL;
 189
 190         /* remove the host bridge */
 191         device_del(&host_bridge->dev);
 192 }
 193 EXPORT_SYMBOL_GPL(pci_remove_root_bus);