of: Fix NULL dereference in unflatten_and_copy()
[firefly-linux-kernel-4.4.55.git] / drivers / pci / remove.c
1 #include <linux/pci.h>
2 #include <linux/module.h>
3 #include <linux/pci-aspm.h>
4 #include "pci.h"
5
6 static void pci_free_resources(struct pci_dev *dev)
7 {
8         int i;
9
10         msi_remove_pci_irq_vectors(dev);
11
12         pci_cleanup_rom(dev);
13         for (i = 0; i < PCI_NUM_RESOURCES; i++) {
14                 struct resource *res = dev->resource + i;
15                 if (res->parent)
16                         release_resource(res);
17         }
18 }
19
20 static void pci_stop_dev(struct pci_dev *dev)
21 {
22         pci_pme_active(dev, false);
23
24         if (dev->is_added) {
25                 pci_proc_detach_device(dev);
26                 pci_remove_sysfs_dev_files(dev);
27                 device_del(&dev->dev);
28                 dev->is_added = 0;
29         }
30
31         if (dev->bus->self)
32                 pcie_aspm_exit_link_state(dev);
33 }
34
35 static void pci_destroy_dev(struct pci_dev *dev)
36 {
37         down_write(&pci_bus_sem);
38         list_del(&dev->bus_list);
39         up_write(&pci_bus_sem);
40
41         pci_free_resources(dev);
42         put_device(&dev->dev);
43 }
44
45 void pci_remove_bus(struct pci_bus *bus)
46 {
47         pci_proc_detach_bus(bus);
48
49         down_write(&pci_bus_sem);
50         list_del(&bus->node);
51         pci_bus_release_busn_res(bus);
52         up_write(&pci_bus_sem);
53         pci_remove_legacy_files(bus);
54         pcibios_remove_bus(bus);
55         device_unregister(&bus->dev);
56 }
57 EXPORT_SYMBOL(pci_remove_bus);
58
59 static void pci_stop_bus_device(struct pci_dev *dev)
60 {
61         struct pci_bus *bus = dev->subordinate;
62         struct pci_dev *child, *tmp;
63
64         /*
65          * Stopping an SR-IOV PF device removes all the associated VFs,
66          * which will update the bus->devices list and confuse the
67          * iterator.  Therefore, iterate in reverse so we remove the VFs
68          * first, then the PF.
69          */
70         if (bus) {
71                 list_for_each_entry_safe_reverse(child, tmp,
72                                                  &bus->devices, bus_list)
73                         pci_stop_bus_device(child);
74         }
75
76         pci_stop_dev(dev);
77 }
78
79 static void pci_remove_bus_device(struct pci_dev *dev)
80 {
81         struct pci_bus *bus = dev->subordinate;
82         struct pci_dev *child, *tmp;
83
84         if (bus) {
85                 list_for_each_entry_safe(child, tmp,
86                                          &bus->devices, bus_list)
87                         pci_remove_bus_device(child);
88
89                 pci_remove_bus(bus);
90                 dev->subordinate = NULL;
91         }
92
93         pci_destroy_dev(dev);
94 }
95
96 /**
97  * pci_stop_and_remove_bus_device - remove a PCI device and any children
98  * @dev: the device to remove
99  *
100  * Remove a PCI device from the device lists, informing the drivers
101  * that the device has been removed.  We also remove any subordinate
102  * buses and children in a depth-first manner.
103  *
104  * For each device we remove, delete the device structure from the
105  * device lists, remove the /proc entry, and notify userspace
106  * (/sbin/hotplug).
107  */
108 void pci_stop_and_remove_bus_device(struct pci_dev *dev)
109 {
110         pci_stop_bus_device(dev);
111         pci_remove_bus_device(dev);
112 }
113 EXPORT_SYMBOL(pci_stop_and_remove_bus_device);
114
115 void pci_stop_root_bus(struct pci_bus *bus)
116 {
117         struct pci_dev *child, *tmp;
118         struct pci_host_bridge *host_bridge;
119
120         if (!pci_is_root_bus(bus))
121                 return;
122
123         host_bridge = to_pci_host_bridge(bus->bridge);
124         list_for_each_entry_safe_reverse(child, tmp,
125                                          &bus->devices, bus_list)
126                 pci_stop_bus_device(child);
127
128         /* stop the host bridge */
129         device_del(&host_bridge->dev);
130 }
131
132 void pci_remove_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(child, tmp,
142                                  &bus->devices, bus_list)
143                 pci_remove_bus_device(child);
144         pci_remove_bus(bus);
145         host_bridge->bus = NULL;
146
147         /* remove the host bridge */
148         put_device(&host_bridge->dev);
149 }