xref: /linux/drivers/pci/remove.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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);
194