1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/pci.h>
3 #include <linux/module.h>
4 #include "pci.h"
5 
pci_free_resources(struct pci_dev * dev)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 
pci_stop_dev(struct pci_dev * dev)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 
23 		device_release_driver(&dev->dev);
24 		pci_proc_detach_device(dev);
25 		pci_remove_sysfs_dev_files(dev);
26 
27 		pci_dev_assign_added(dev, false);
28 	}
29 }
30 
pci_destroy_dev(struct pci_dev * dev)31 static void pci_destroy_dev(struct pci_dev *dev)
32 {
33 	if (!dev->dev.kobj.parent)
34 		return;
35 
36 	device_del(&dev->dev);
37 
38 	down_write(&pci_bus_sem);
39 	list_del(&dev->bus_list);
40 	up_write(&pci_bus_sem);
41 
42 	pcie_aspm_exit_link_state(dev);
43 	pci_bridge_d3_update(dev);
44 	pci_free_resources(dev);
45 	put_device(&dev->dev);
46 }
47 
pci_remove_bus(struct pci_bus * bus)48 void pci_remove_bus(struct pci_bus *bus)
49 {
50 	pci_proc_detach_bus(bus);
51 
52 	down_write(&pci_bus_sem);
53 	list_del(&bus->node);
54 	pci_bus_release_busn_res(bus);
55 	up_write(&pci_bus_sem);
56 	pci_remove_legacy_files(bus);
57 
58 	if (bus->ops->remove_bus)
59 		bus->ops->remove_bus(bus);
60 
61 	pcibios_remove_bus(bus);
62 	device_unregister(&bus->dev);
63 }
64 EXPORT_SYMBOL(pci_remove_bus);
65 
pci_stop_bus_device(struct pci_dev * dev)66 static void pci_stop_bus_device(struct pci_dev *dev)
67 {
68 	struct pci_bus *bus = dev->subordinate;
69 	struct pci_dev *child, *tmp;
70 
71 	/*
72 	 * Stopping an SR-IOV PF device removes all the associated VFs,
73 	 * which will update the bus->devices list and confuse the
74 	 * iterator.  Therefore, iterate in reverse so we remove the VFs
75 	 * first, then the PF.
76 	 */
77 	if (bus) {
78 		list_for_each_entry_safe_reverse(child, tmp,
79 						 &bus->devices, bus_list)
80 			pci_stop_bus_device(child);
81 	}
82 
83 	pci_stop_dev(dev);
84 }
85 
pci_remove_bus_device(struct pci_dev * dev)86 static void pci_remove_bus_device(struct pci_dev *dev)
87 {
88 	struct pci_bus *bus = dev->subordinate;
89 	struct pci_dev *child, *tmp;
90 
91 	if (bus) {
92 		list_for_each_entry_safe(child, tmp,
93 					 &bus->devices, bus_list)
94 			pci_remove_bus_device(child);
95 
96 		pci_remove_bus(bus);
97 		dev->subordinate = NULL;
98 	}
99 
100 	pci_destroy_dev(dev);
101 }
102 
103 /**
104  * pci_stop_and_remove_bus_device - remove a PCI device and any children
105  * @dev: the device to remove
106  *
107  * Remove a PCI device from the device lists, informing the drivers
108  * that the device has been removed.  We also remove any subordinate
109  * buses and children in a depth-first manner.
110  *
111  * For each device we remove, delete the device structure from the
112  * device lists, remove the /proc entry, and notify userspace
113  * (/sbin/hotplug).
114  */
pci_stop_and_remove_bus_device(struct pci_dev * dev)115 void pci_stop_and_remove_bus_device(struct pci_dev *dev)
116 {
117 	pci_stop_bus_device(dev);
118 	pci_remove_bus_device(dev);
119 }
120 EXPORT_SYMBOL(pci_stop_and_remove_bus_device);
121 
pci_stop_and_remove_bus_device_locked(struct pci_dev * dev)122 void pci_stop_and_remove_bus_device_locked(struct pci_dev *dev)
123 {
124 	pci_lock_rescan_remove();
125 	pci_stop_and_remove_bus_device(dev);
126 	pci_unlock_rescan_remove();
127 }
128 EXPORT_SYMBOL_GPL(pci_stop_and_remove_bus_device_locked);
129 
pci_stop_root_bus(struct pci_bus * bus)130 void pci_stop_root_bus(struct pci_bus *bus)
131 {
132 	struct pci_dev *child, *tmp;
133 	struct pci_host_bridge *host_bridge;
134 
135 	if (!pci_is_root_bus(bus))
136 		return;
137 
138 	host_bridge = to_pci_host_bridge(bus->bridge);
139 	list_for_each_entry_safe_reverse(child, tmp,
140 					 &bus->devices, bus_list)
141 		pci_stop_bus_device(child);
142 
143 	/* stop the host bridge */
144 	device_release_driver(&host_bridge->dev);
145 }
146 EXPORT_SYMBOL_GPL(pci_stop_root_bus);
147 
pci_remove_root_bus(struct pci_bus * bus)148 void pci_remove_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(child, tmp,
158 				 &bus->devices, bus_list)
159 		pci_remove_bus_device(child);
160 	pci_remove_bus(bus);
161 	host_bridge->bus = NULL;
162 
163 	/* remove the host bridge */
164 	device_del(&host_bridge->dev);
165 }
166 EXPORT_SYMBOL_GPL(pci_remove_root_bus);
167