xref: /linux/drivers/pci/remove.c (revision 2dbc0838bcf24ca59cabc3130cf3b1d6809cdcd4)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/pci.h>
3 #include <linux/module.h>
4 #include "pci.h"
5 
6 static void pci_free_resources(struct pci_dev *dev)
7 {
8 	int i;
9 
10 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
11 		struct resource *res = dev->resource + i;
12 		if (res->parent)
13 			release_resource(res);
14 	}
15 }
16 
17 static void pci_stop_dev(struct pci_dev *dev)
18 {
19 	pci_pme_active(dev, false);
20 
21 	if (pci_dev_is_added(dev)) {
22 		device_release_driver(&dev->dev);
23 		pci_proc_detach_device(dev);
24 		pci_remove_sysfs_dev_files(dev);
25 
26 		pci_dev_assign_added(dev, false);
27 	}
28 }
29 
30 static void pci_destroy_dev(struct pci_dev *dev)
31 {
32 	if (!dev->dev.kobj.parent)
33 		return;
34 
35 	device_del(&dev->dev);
36 
37 	down_write(&pci_bus_sem);
38 	list_del(&dev->bus_list);
39 	up_write(&pci_bus_sem);
40 
41 	pcie_aspm_exit_link_state(dev);
42 	pci_bridge_d3_update(dev);
43 	pci_free_resources(dev);
44 	put_device(&dev->dev);
45 }
46 
47 void pci_remove_bus(struct pci_bus *bus)
48 {
49 	pci_proc_detach_bus(bus);
50 
51 	down_write(&pci_bus_sem);
52 	list_del(&bus->node);
53 	pci_bus_release_busn_res(bus);
54 	up_write(&pci_bus_sem);
55 	pci_remove_legacy_files(bus);
56 
57 	if (bus->ops->remove_bus)
58 		bus->ops->remove_bus(bus);
59 
60 	pcibios_remove_bus(bus);
61 	device_unregister(&bus->dev);
62 }
63 EXPORT_SYMBOL(pci_remove_bus);
64 
65 static void pci_stop_bus_device(struct pci_dev *dev)
66 {
67 	struct pci_bus *bus = dev->subordinate;
68 	struct pci_dev *child, *tmp;
69 
70 	/*
71 	 * Stopping an SR-IOV PF device removes all the associated VFs,
72 	 * which will update the bus->devices list and confuse the
73 	 * iterator.  Therefore, iterate in reverse so we remove the VFs
74 	 * first, then the PF.
75 	 */
76 	if (bus) {
77 		list_for_each_entry_safe_reverse(child, tmp,
78 						 &bus->devices, bus_list)
79 			pci_stop_bus_device(child);
80 	}
81 
82 	pci_stop_dev(dev);
83 }
84 
85 static void pci_remove_bus_device(struct pci_dev *dev)
86 {
87 	struct pci_bus *bus = dev->subordinate;
88 	struct pci_dev *child, *tmp;
89 
90 	if (bus) {
91 		list_for_each_entry_safe(child, tmp,
92 					 &bus->devices, bus_list)
93 			pci_remove_bus_device(child);
94 
95 		pci_remove_bus(bus);
96 		dev->subordinate = NULL;
97 	}
98 
99 	pci_destroy_dev(dev);
100 }
101 
102 /**
103  * pci_stop_and_remove_bus_device - remove a PCI device and any children
104  * @dev: the device to remove
105  *
106  * Remove a PCI device from the device lists, informing the drivers
107  * that the device has been removed.  We also remove any subordinate
108  * buses and children in a depth-first manner.
109  *
110  * For each device we remove, delete the device structure from the
111  * device lists, remove the /proc entry, and notify userspace
112  * (/sbin/hotplug).
113  */
114 void pci_stop_and_remove_bus_device(struct pci_dev *dev)
115 {
116 	pci_stop_bus_device(dev);
117 	pci_remove_bus_device(dev);
118 }
119 EXPORT_SYMBOL(pci_stop_and_remove_bus_device);
120 
121 void pci_stop_and_remove_bus_device_locked(struct pci_dev *dev)
122 {
123 	pci_lock_rescan_remove();
124 	pci_stop_and_remove_bus_device(dev);
125 	pci_unlock_rescan_remove();
126 }
127 EXPORT_SYMBOL_GPL(pci_stop_and_remove_bus_device_locked);
128 
129 void pci_stop_root_bus(struct pci_bus *bus)
130 {
131 	struct pci_dev *child, *tmp;
132 	struct pci_host_bridge *host_bridge;
133 
134 	if (!pci_is_root_bus(bus))
135 		return;
136 
137 	host_bridge = to_pci_host_bridge(bus->bridge);
138 	list_for_each_entry_safe_reverse(child, tmp,
139 					 &bus->devices, bus_list)
140 		pci_stop_bus_device(child);
141 
142 	/* stop the host bridge */
143 	device_release_driver(&host_bridge->dev);
144 }
145 EXPORT_SYMBOL_GPL(pci_stop_root_bus);
146 
147 void pci_remove_root_bus(struct pci_bus *bus)
148 {
149 	struct pci_dev *child, *tmp;
150 	struct pci_host_bridge *host_bridge;
151 
152 	if (!pci_is_root_bus(bus))
153 		return;
154 
155 	host_bridge = to_pci_host_bridge(bus->bridge);
156 	list_for_each_entry_safe(child, tmp,
157 				 &bus->devices, bus_list)
158 		pci_remove_bus_device(child);
159 	pci_remove_bus(bus);
160 	host_bridge->bus = NULL;
161 
162 	/* remove the host bridge */
163 	device_unregister(&host_bridge->dev);
164 }
165 EXPORT_SYMBOL_GPL(pci_remove_root_bus);
166