xref: /linux/drivers/pci/remove.c (revision a1aed6b34ff4545803673a8d2e4e1f865ee3746d)
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 	device_release_driver(&dev->dev);
45 	pci_proc_detach_device(dev);
46 	pci_remove_sysfs_dev_files(dev);
47 	of_pci_remove_node(dev);
48 }
49 
50 static void pci_destroy_dev(struct pci_dev *dev)
51 {
52 	if (pci_dev_test_and_set_removed(dev))
53 		return;
54 
55 	pci_doe_sysfs_teardown(dev);
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_pwrctrl_unregister(&dev->dev);
68 	pci_free_resources(dev);
69 	put_device(&dev->dev);
70 }
71 
72 void pci_remove_bus(struct pci_bus *bus)
73 {
74 	pci_proc_detach_bus(bus);
75 
76 	down_write(&pci_bus_sem);
77 	list_del(&bus->node);
78 	pci_bus_release_busn_res(bus);
79 	up_write(&pci_bus_sem);
80 	pci_remove_legacy_files(bus);
81 
82 	if (bus->ops->remove_bus)
83 		bus->ops->remove_bus(bus);
84 
85 	pcibios_remove_bus(bus);
86 	device_unregister(&bus->dev);
87 }
88 EXPORT_SYMBOL(pci_remove_bus);
89 
90 static void pci_stop_bus_device(struct pci_dev *dev)
91 {
92 	struct pci_bus *bus = dev->subordinate;
93 	struct pci_dev *child, *tmp;
94 
95 	/*
96 	 * Stopping an SR-IOV PF device removes all the associated VFs,
97 	 * which will update the bus->devices list and confuse the
98 	 * iterator.  Therefore, iterate in reverse so we remove the VFs
99 	 * first, then the PF.
100 	 */
101 	if (bus) {
102 		list_for_each_entry_safe_reverse(child, tmp,
103 						 &bus->devices, bus_list)
104 			pci_stop_bus_device(child);
105 	}
106 
107 	pci_stop_dev(dev);
108 }
109 
110 static void pci_remove_bus_device(struct pci_dev *dev)
111 {
112 	struct pci_bus *bus = dev->subordinate;
113 	struct pci_dev *child, *tmp;
114 
115 	if (bus) {
116 		list_for_each_entry_safe(child, tmp,
117 					 &bus->devices, bus_list)
118 			pci_remove_bus_device(child);
119 
120 		pci_remove_bus(bus);
121 		dev->subordinate = NULL;
122 	}
123 
124 	pci_destroy_dev(dev);
125 }
126 
127 /**
128  * pci_stop_and_remove_bus_device - remove a PCI device and any children
129  * @dev: the device to remove
130  *
131  * Remove a PCI device from the device lists, informing the drivers
132  * that the device has been removed.  We also remove any subordinate
133  * buses and children in a depth-first manner.
134  *
135  * For each device we remove, delete the device structure from the
136  * device lists, remove the /proc entry, and notify userspace
137  * (/sbin/hotplug).
138  */
139 void pci_stop_and_remove_bus_device(struct pci_dev *dev)
140 {
141 	pci_stop_bus_device(dev);
142 	pci_remove_bus_device(dev);
143 }
144 EXPORT_SYMBOL(pci_stop_and_remove_bus_device);
145 
146 void pci_stop_and_remove_bus_device_locked(struct pci_dev *dev)
147 {
148 	pci_lock_rescan_remove();
149 	pci_stop_and_remove_bus_device(dev);
150 	pci_unlock_rescan_remove();
151 }
152 EXPORT_SYMBOL_GPL(pci_stop_and_remove_bus_device_locked);
153 
154 void pci_stop_root_bus(struct pci_bus *bus)
155 {
156 	struct pci_dev *child, *tmp;
157 	struct pci_host_bridge *host_bridge;
158 
159 	if (!pci_is_root_bus(bus))
160 		return;
161 
162 	host_bridge = to_pci_host_bridge(bus->bridge);
163 	list_for_each_entry_safe_reverse(child, tmp,
164 					 &bus->devices, bus_list)
165 		pci_stop_bus_device(child);
166 
167 	of_pci_remove_host_bridge_node(host_bridge);
168 
169 	/* stop the host bridge */
170 	device_release_driver(&host_bridge->dev);
171 }
172 EXPORT_SYMBOL_GPL(pci_stop_root_bus);
173 
174 void pci_remove_root_bus(struct pci_bus *bus)
175 {
176 	struct pci_dev *child, *tmp;
177 	struct pci_host_bridge *host_bridge;
178 
179 	if (!pci_is_root_bus(bus))
180 		return;
181 
182 	host_bridge = to_pci_host_bridge(bus->bridge);
183 	list_for_each_entry_safe(child, tmp,
184 				 &bus->devices, bus_list)
185 		pci_remove_bus_device(child);
186 
187 #ifdef CONFIG_PCI_DOMAINS_GENERIC
188 	/* Release domain_nr if it was dynamically allocated */
189 	if (host_bridge->domain_nr == PCI_DOMAIN_NR_NOT_SET)
190 		pci_bus_release_domain_nr(host_bridge->dev.parent, bus->domain_nr);
191 #endif
192 
193 	pci_remove_bus(bus);
194 	host_bridge->bus = NULL;
195 
196 	/* remove the host bridge */
197 	device_del(&host_bridge->dev);
198 }
199 EXPORT_SYMBOL_GPL(pci_remove_root_bus);
200