xref: /openbmc/linux/drivers/pci/remove.c (revision 63dc02bd)
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 	if (dev->is_added) {
23 		pci_proc_detach_device(dev);
24 		pci_remove_sysfs_dev_files(dev);
25 		device_unregister(&dev->dev);
26 		dev->is_added = 0;
27 	}
28 
29 	if (dev->bus->self)
30 		pcie_aspm_exit_link_state(dev);
31 }
32 
33 static void pci_destroy_dev(struct pci_dev *dev)
34 {
35 	/* Remove the device from the device lists, and prevent any further
36 	 * list accesses from this device */
37 	down_write(&pci_bus_sem);
38 	list_del(&dev->bus_list);
39 	dev->bus_list.next = dev->bus_list.prev = NULL;
40 	up_write(&pci_bus_sem);
41 
42 	pci_free_resources(dev);
43 	pci_dev_put(dev);
44 }
45 
46 /**
47  * pci_remove_device_safe - remove an unused hotplug device
48  * @dev: the device to remove
49  *
50  * Delete the device structure from the device lists and
51  * notify userspace (/sbin/hotplug), but only if the device
52  * in question is not being used by a driver.
53  * Returns 0 on success.
54  */
55 #if 0
56 int pci_remove_device_safe(struct pci_dev *dev)
57 {
58 	if (pci_dev_driver(dev))
59 		return -EBUSY;
60 	pci_destroy_dev(dev);
61 	return 0;
62 }
63 #endif  /*  0  */
64 
65 void pci_remove_bus(struct pci_bus *pci_bus)
66 {
67 	pci_proc_detach_bus(pci_bus);
68 
69 	down_write(&pci_bus_sem);
70 	list_del(&pci_bus->node);
71 	up_write(&pci_bus_sem);
72 	if (!pci_bus->is_added)
73 		return;
74 
75 	pci_remove_legacy_files(pci_bus);
76 	device_unregister(&pci_bus->dev);
77 }
78 EXPORT_SYMBOL(pci_remove_bus);
79 
80 static void __pci_remove_behind_bridge(struct pci_dev *dev);
81 /**
82  * pci_stop_and_remove_bus_device - remove a PCI device and any children
83  * @dev: the device to remove
84  *
85  * Remove a PCI device from the device lists, informing the drivers
86  * that the device has been removed.  We also remove any subordinate
87  * buses and children in a depth-first manner.
88  *
89  * For each device we remove, delete the device structure from the
90  * device lists, remove the /proc entry, and notify userspace
91  * (/sbin/hotplug).
92  */
93 void __pci_remove_bus_device(struct pci_dev *dev)
94 {
95 	if (dev->subordinate) {
96 		struct pci_bus *b = dev->subordinate;
97 
98 		__pci_remove_behind_bridge(dev);
99 		pci_remove_bus(b);
100 		dev->subordinate = NULL;
101 	}
102 
103 	pci_destroy_dev(dev);
104 }
105 EXPORT_SYMBOL(__pci_remove_bus_device);
106 
107 void pci_stop_and_remove_bus_device(struct pci_dev *dev)
108 {
109 	pci_stop_bus_device(dev);
110 	__pci_remove_bus_device(dev);
111 }
112 
113 static void __pci_remove_behind_bridge(struct pci_dev *dev)
114 {
115 	struct list_head *l, *n;
116 
117 	if (dev->subordinate)
118 		list_for_each_safe(l, n, &dev->subordinate->devices)
119 			__pci_remove_bus_device(pci_dev_b(l));
120 }
121 
122 static void pci_stop_behind_bridge(struct pci_dev *dev)
123 {
124 	struct list_head *l, *n;
125 
126 	if (dev->subordinate)
127 		list_for_each_safe(l, n, &dev->subordinate->devices)
128 			pci_stop_bus_device(pci_dev_b(l));
129 }
130 
131 /**
132  * pci_stop_and_remove_behind_bridge - stop and remove all devices behind
133  *					 a PCI bridge
134  * @dev: PCI bridge device
135  *
136  * Remove all devices on the bus, except for the parent bridge.
137  * This also removes any child buses, and any devices they may
138  * contain in a depth-first manner.
139  */
140 void pci_stop_and_remove_behind_bridge(struct pci_dev *dev)
141 {
142 	pci_stop_behind_bridge(dev);
143 	__pci_remove_behind_bridge(dev);
144 }
145 
146 static void pci_stop_bus_devices(struct pci_bus *bus)
147 {
148 	struct list_head *l, *n;
149 
150 	/*
151 	 * VFs could be removed by pci_stop_and_remove_bus_device() in the
152 	 *  pci_stop_bus_devices() code path for PF.
153 	 *  aka, bus->devices get updated in the process.
154 	 * but VFs are inserted after PFs when SRIOV is enabled for PF,
155 	 * We can iterate the list backwards to get prev valid PF instead
156 	 *  of removed VF.
157 	 */
158 	list_for_each_prev_safe(l, n, &bus->devices) {
159 		struct pci_dev *dev = pci_dev_b(l);
160 		pci_stop_bus_device(dev);
161 	}
162 }
163 
164 /**
165  * pci_stop_bus_device - stop a PCI device and any children
166  * @dev: the device to stop
167  *
168  * Stop a PCI device (detach the driver, remove from the global list
169  * and so on). This also stop any subordinate buses and children in a
170  * depth-first manner.
171  */
172 void pci_stop_bus_device(struct pci_dev *dev)
173 {
174 	if (dev->subordinate)
175 		pci_stop_bus_devices(dev->subordinate);
176 
177 	pci_stop_dev(dev);
178 }
179 
180 EXPORT_SYMBOL(pci_stop_and_remove_bus_device);
181 EXPORT_SYMBOL(pci_stop_and_remove_behind_bridge);
182 EXPORT_SYMBOL_GPL(pci_stop_bus_device);
183