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 device_node *np;
  23         struct platform_device *pdev;
  24
  25         np = dev_of_node(dev);
  26         if (!np)
  27                 return;
  28
  29         pdev = of_find_device_by_node(np);
  30         if (!pdev)
  31                 return;
  32
  33         of_device_unregister(pdev);
  34         of_node_clear_flag(np, OF_POPULATED);
  35 }
  36
  37 static void pci_stop_dev(struct pci_dev *dev)
  38 {
  39         pci_pme_active(dev, false);
  40
  41         if (!pci_dev_test_and_clear_added(dev))
  42                 return;
  43
  44         pci_pwrctrl_unregister(&dev->dev);
  45         device_release_driver(&dev->dev);
  46         pci_proc_detach_device(dev);
  47         pci_remove_sysfs_dev_files(dev);
  48         of_pci_remove_node(dev);
  49 }
  50
  51 static void pci_destroy_dev(struct pci_dev *dev)
  52 {
  53         if (pci_dev_test_and_set_removed(dev))
  54                 return;
  55
  56         pci_npem_remove(dev);
  57
  58         device_del(&dev->dev);
  59
  60         down_write(&pci_bus_sem);
  61         list_del(&dev->bus_list);
  62         up_write(&pci_bus_sem);
  63
  64         pci_doe_destroy(dev);
  65         pcie_aspm_exit_link_state(dev);
  66         pci_bridge_d3_update(dev);
  67         pci_free_resources(dev);
  68         put_device(&dev->dev);
  69 }
  70
  71 void pci_remove_bus(struct pci_bus *bus)
  72 {
  73         pci_proc_detach_bus(bus);
  74
  75         down_write(&pci_bus_sem);
  76         list_del(&bus->node);
  77         pci_bus_release_busn_res(bus);
  78         up_write(&pci_bus_sem);
  79         pci_remove_legacy_files(bus);
  80
  81         if (bus->ops->remove_bus)
  82                 bus->ops->remove_bus(bus);
  83
  84         pcibios_remove_bus(bus);
  85         device_unregister(&bus->dev);
  86 }
  87 EXPORT_SYMBOL(pci_remove_bus);
  88
  89 static void pci_stop_bus_device(struct pci_dev *dev)
  90 {
  91         struct pci_bus *bus = dev->subordinate;
  92         struct pci_dev *child, *tmp;
  93
  94         /*
  95          * Stopping an SR-IOV PF device removes all the associated VFs,
  96          * which will update the bus->devices list and confuse the
  97          * iterator.  Therefore, iterate in reverse so we remove the VFs
  98          * first, then the PF.
  99          */
 100         if (bus) {
 101                 list_for_each_entry_safe_reverse(child, tmp,
 102                                                  &bus->devices, bus_list)
 103                         pci_stop_bus_device(child);
 104         }
 105
 106         pci_stop_dev(dev);
 107 }
 108
 109 static void pci_remove_bus_device(struct pci_dev *dev)
 110 {
 111         struct pci_bus *bus = dev->subordinate;
 112         struct pci_dev *child, *tmp;
 113
 114         if (bus) {
 115                 list_for_each_entry_safe(child, tmp,
 116                                          &bus->devices, bus_list)
 117                         pci_remove_bus_device(child);
 118
 119                 pci_remove_bus(bus);
 120                 dev->subordinate = NULL;
 121         }
 122
 123         pci_destroy_dev(dev);
 124 }
 125
 126 /**
 127  * pci_stop_and_remove_bus_device - remove a PCI device and any children
 128  * @dev: the device to remove
 129  *
 130  * Remove a PCI device from the device lists, informing the drivers
 131  * that the device has been removed.  We also remove any subordinate
 132  * buses and children in a depth-first manner.
 133  *
 134  * For each device we remove, delete the device structure from the
 135  * device lists, remove the /proc entry, and notify userspace
 136  * (/sbin/hotplug).
 137  */
 138 void pci_stop_and_remove_bus_device(struct pci_dev *dev)
 139 {
 140         pci_stop_bus_device(dev);
 141         pci_remove_bus_device(dev);
 142 }
 143 EXPORT_SYMBOL(pci_stop_and_remove_bus_device);
 144
 145 void pci_stop_and_remove_bus_device_locked(struct pci_dev *dev)
 146 {
 147         pci_lock_rescan_remove();
 148         pci_stop_and_remove_bus_device(dev);
 149         pci_unlock_rescan_remove();
 150 }
 151 EXPORT_SYMBOL_GPL(pci_stop_and_remove_bus_device_locked);
 152
 153 void pci_stop_root_bus(struct pci_bus *bus)
 154 {
 155         struct pci_dev *child, *tmp;
 156         struct pci_host_bridge *host_bridge;
 157
 158         if (!pci_is_root_bus(bus))
 159                 return;
 160
 161         host_bridge = to_pci_host_bridge(bus->bridge);
 162         list_for_each_entry_safe_reverse(child, tmp,
 163                                          &bus->devices, bus_list)
 164                 pci_stop_bus_device(child);
 165
 166         /* stop the host bridge */
 167         device_release_driver(&host_bridge->dev);
 168 }
 169 EXPORT_SYMBOL_GPL(pci_stop_root_bus);
 170
 171 void pci_remove_root_bus(struct pci_bus *bus)
 172 {
 173         struct pci_dev *child, *tmp;
 174         struct pci_host_bridge *host_bridge;
 175
 176         if (!pci_is_root_bus(bus))
 177                 return;
 178
 179         host_bridge = to_pci_host_bridge(bus->bridge);
 180         list_for_each_entry_safe(child, tmp,
 181                                  &bus->devices, bus_list)
 182                 pci_remove_bus_device(child);
 183
 184 #ifdef CONFIG_PCI_DOMAINS_GENERIC
 185         /* Release domain_nr if it was dynamically allocated */
 186         if (host_bridge->domain_nr == PCI_DOMAIN_NR_NOT_SET)
 187                 pci_bus_release_domain_nr(host_bridge->dev.parent, bus->domain_nr);
 188 #endif
 189
 190         pci_remove_bus(bus);
 191         host_bridge->bus = NULL;
 192
 193         /* remove the host bridge */
 194         device_del(&host_bridge->dev);
 195 }
 196 EXPORT_SYMBOL_GPL(pci_remove_root_bus);