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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2006 Matthew Wilcox <matthew@wil.cx>
4 * Copyright (C) 2006-2009 Hewlett-Packard Development Company, L.P.
5 * Alex Chiang <achiang@hp.com>
6 */
7
8#include <linux/kobject.h>
9#include <linux/slab.h>
10#include <linux/module.h>
11#include <linux/pci.h>
12#include <linux/err.h>
13#include "pci.h"
14
15struct kset *pci_slots_kset;
16EXPORT_SYMBOL_GPL(pci_slots_kset);
17
18static ssize_t pci_slot_attr_show(struct kobject *kobj,
19 struct attribute *attr, char *buf)
20{
21 struct pci_slot *slot = to_pci_slot(kobj);
22 struct pci_slot_attribute *attribute = to_pci_slot_attr(attr);
23 return attribute->show ? attribute->show(slot, buf) : -EIO;
24}
25
26static ssize_t pci_slot_attr_store(struct kobject *kobj,
27 struct attribute *attr, const char *buf, size_t len)
28{
29 struct pci_slot *slot = to_pci_slot(kobj);
30 struct pci_slot_attribute *attribute = to_pci_slot_attr(attr);
31 return attribute->store ? attribute->store(slot, buf, len) : -EIO;
32}
33
34static const struct sysfs_ops pci_slot_sysfs_ops = {
35 .show = pci_slot_attr_show,
36 .store = pci_slot_attr_store,
37};
38
39static ssize_t address_read_file(struct pci_slot *slot, char *buf)
40{
41 if (slot->number == 0xff)
42 return sprintf(buf, "%04x:%02x\n",
43 pci_domain_nr(slot->bus),
44 slot->bus->number);
45 else
46 return sprintf(buf, "%04x:%02x:%02x\n",
47 pci_domain_nr(slot->bus),
48 slot->bus->number,
49 slot->number);
50}
51
52static ssize_t bus_speed_read(enum pci_bus_speed speed, char *buf)
53{
54 return sprintf(buf, "%s\n", pci_speed_string(speed));
55}
56
57static ssize_t max_speed_read_file(struct pci_slot *slot, char *buf)
58{
59 return bus_speed_read(slot->bus->max_bus_speed, buf);
60}
61
62static ssize_t cur_speed_read_file(struct pci_slot *slot, char *buf)
63{
64 return bus_speed_read(slot->bus->cur_bus_speed, buf);
65}
66
67static void pci_slot_release(struct kobject *kobj)
68{
69 struct pci_dev *dev;
70 struct pci_slot *slot = to_pci_slot(kobj);
71
72 dev_dbg(&slot->bus->dev, "dev %02x, released physical slot %s\n",
73 slot->number, pci_slot_name(slot));
74
75 down_read(&pci_bus_sem);
76 list_for_each_entry(dev, &slot->bus->devices, bus_list)
77 if (PCI_SLOT(dev->devfn) == slot->number)
78 dev->slot = NULL;
79 up_read(&pci_bus_sem);
80
81 list_del(&slot->list);
82
83 kfree(slot);
84}
85
86static struct pci_slot_attribute pci_slot_attr_address =
87 __ATTR(address, S_IRUGO, address_read_file, NULL);
88static struct pci_slot_attribute pci_slot_attr_max_speed =
89 __ATTR(max_bus_speed, S_IRUGO, max_speed_read_file, NULL);
90static struct pci_slot_attribute pci_slot_attr_cur_speed =
91 __ATTR(cur_bus_speed, S_IRUGO, cur_speed_read_file, NULL);
92
93static struct attribute *pci_slot_default_attrs[] = {
94 &pci_slot_attr_address.attr,
95 &pci_slot_attr_max_speed.attr,
96 &pci_slot_attr_cur_speed.attr,
97 NULL,
98};
99
100static struct kobj_type pci_slot_ktype = {
101 .sysfs_ops = &pci_slot_sysfs_ops,
102 .release = &pci_slot_release,
103 .default_attrs = pci_slot_default_attrs,
104};
105
106static char *make_slot_name(const char *name)
107{
108 char *new_name;
109 int len, max, dup;
110
111 new_name = kstrdup(name, GFP_KERNEL);
112 if (!new_name)
113 return NULL;
114
115 /*
116 * Make sure we hit the realloc case the first time through the
117 * loop. 'len' will be strlen(name) + 3 at that point which is
118 * enough space for "name-X" and the trailing NUL.
119 */
120 len = strlen(name) + 2;
121 max = 1;
122 dup = 1;
123
124 for (;;) {
125 struct kobject *dup_slot;
126 dup_slot = kset_find_obj(pci_slots_kset, new_name);
127 if (!dup_slot)
128 break;
129 kobject_put(dup_slot);
130 if (dup == max) {
131 len++;
132 max *= 10;
133 kfree(new_name);
134 new_name = kmalloc(len, GFP_KERNEL);
135 if (!new_name)
136 break;
137 }
138 sprintf(new_name, "%s-%d", name, dup++);
139 }
140
141 return new_name;
142}
143
144static int rename_slot(struct pci_slot *slot, const char *name)
145{
146 int result = 0;
147 char *slot_name;
148
149 if (strcmp(pci_slot_name(slot), name) == 0)
150 return result;
151
152 slot_name = make_slot_name(name);
153 if (!slot_name)
154 return -ENOMEM;
155
156 result = kobject_rename(&slot->kobj, slot_name);
157 kfree(slot_name);
158
159 return result;
160}
161
162void pci_dev_assign_slot(struct pci_dev *dev)
163{
164 struct pci_slot *slot;
165
166 mutex_lock(&pci_slot_mutex);
167 list_for_each_entry(slot, &dev->bus->slots, list)
168 if (PCI_SLOT(dev->devfn) == slot->number)
169 dev->slot = slot;
170 mutex_unlock(&pci_slot_mutex);
171}
172
173static struct pci_slot *get_slot(struct pci_bus *parent, int slot_nr)
174{
175 struct pci_slot *slot;
176
177 /* We already hold pci_slot_mutex */
178 list_for_each_entry(slot, &parent->slots, list)
179 if (slot->number == slot_nr) {
180 kobject_get(&slot->kobj);
181 return slot;
182 }
183
184 return NULL;
185}
186
187/**
188 * pci_create_slot - create or increment refcount for physical PCI slot
189 * @parent: struct pci_bus of parent bridge
190 * @slot_nr: PCI_SLOT(pci_dev->devfn) or -1 for placeholder
191 * @name: user visible string presented in /sys/bus/pci/slots/<name>
192 * @hotplug: set if caller is hotplug driver, NULL otherwise
193 *
194 * PCI slots have first class attributes such as address, speed, width,
195 * and a &struct pci_slot is used to manage them. This interface will
196 * either return a new &struct pci_slot to the caller, or if the pci_slot
197 * already exists, its refcount will be incremented.
198 *
199 * Slots are uniquely identified by a @pci_bus, @slot_nr tuple.
200 *
201 * There are known platforms with broken firmware that assign the same
202 * name to multiple slots. Workaround these broken platforms by renaming
203 * the slots on behalf of the caller. If firmware assigns name N to
204 * multiple slots:
205 *
206 * The first slot is assigned N
207 * The second slot is assigned N-1
208 * The third slot is assigned N-2
209 * etc.
210 *
211 * Placeholder slots:
212 * In most cases, @pci_bus, @slot_nr will be sufficient to uniquely identify
213 * a slot. There is one notable exception - pSeries (rpaphp), where the
214 * @slot_nr cannot be determined until a device is actually inserted into
215 * the slot. In this scenario, the caller may pass -1 for @slot_nr.
216 *
217 * The following semantics are imposed when the caller passes @slot_nr ==
218 * -1. First, we no longer check for an existing %struct pci_slot, as there
219 * may be many slots with @slot_nr of -1. The other change in semantics is
220 * user-visible, which is the 'address' parameter presented in sysfs will
221 * consist solely of a dddd:bb tuple, where dddd is the PCI domain of the
222 * %struct pci_bus and bb is the bus number. In other words, the devfn of
223 * the 'placeholder' slot will not be displayed.
224 */
225struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr,
226 const char *name,
227 struct hotplug_slot *hotplug)
228{
229 struct pci_dev *dev;
230 struct pci_slot *slot;
231 int err = 0;
232 char *slot_name = NULL;
233
234 mutex_lock(&pci_slot_mutex);
235
236 if (slot_nr == -1)
237 goto placeholder;
238
239 /*
240 * Hotplug drivers are allowed to rename an existing slot,
241 * but only if not already claimed.
242 */
243 slot = get_slot(parent, slot_nr);
244 if (slot) {
245 if (hotplug) {
246 if ((err = slot->hotplug ? -EBUSY : 0)
247 || (err = rename_slot(slot, name))) {
248 kobject_put(&slot->kobj);
249 slot = NULL;
250 goto err;
251 }
252 }
253 goto out;
254 }
255
256placeholder:
257 slot = kzalloc(sizeof(*slot), GFP_KERNEL);
258 if (!slot) {
259 err = -ENOMEM;
260 goto err;
261 }
262
263 slot->bus = parent;
264 slot->number = slot_nr;
265
266 slot->kobj.kset = pci_slots_kset;
267
268 slot_name = make_slot_name(name);
269 if (!slot_name) {
270 err = -ENOMEM;
271 kfree(slot);
272 goto err;
273 }
274
275 err = kobject_init_and_add(&slot->kobj, &pci_slot_ktype, NULL,
276 "%s", slot_name);
277 if (err) {
278 kobject_put(&slot->kobj);
279 goto err;
280 }
281
282 INIT_LIST_HEAD(&slot->list);
283 list_add(&slot->list, &parent->slots);
284
285 down_read(&pci_bus_sem);
286 list_for_each_entry(dev, &parent->devices, bus_list)
287 if (PCI_SLOT(dev->devfn) == slot_nr)
288 dev->slot = slot;
289 up_read(&pci_bus_sem);
290
291 dev_dbg(&parent->dev, "dev %02x, created physical slot %s\n",
292 slot_nr, pci_slot_name(slot));
293
294out:
295 kfree(slot_name);
296 mutex_unlock(&pci_slot_mutex);
297 return slot;
298err:
299 slot = ERR_PTR(err);
300 goto out;
301}
302EXPORT_SYMBOL_GPL(pci_create_slot);
303
304/**
305 * pci_destroy_slot - decrement refcount for physical PCI slot
306 * @slot: struct pci_slot to decrement
307 *
308 * %struct pci_slot is refcounted, so destroying them is really easy; we
309 * just call kobject_put on its kobj and let our release methods do the
310 * rest.
311 */
312void pci_destroy_slot(struct pci_slot *slot)
313{
314 dev_dbg(&slot->bus->dev, "dev %02x, dec refcount to %d\n",
315 slot->number, kref_read(&slot->kobj.kref) - 1);
316
317 mutex_lock(&pci_slot_mutex);
318 kobject_put(&slot->kobj);
319 mutex_unlock(&pci_slot_mutex);
320}
321EXPORT_SYMBOL_GPL(pci_destroy_slot);
322
323#if defined(CONFIG_HOTPLUG_PCI) || defined(CONFIG_HOTPLUG_PCI_MODULE)
324#include <linux/pci_hotplug.h>
325/**
326 * pci_hp_create_link - create symbolic link to the hotplug driver module.
327 * @pci_slot: struct pci_slot
328 *
329 * Helper function for pci_hotplug_core.c to create symbolic link to
330 * the hotplug driver module.
331 */
332void pci_hp_create_module_link(struct pci_slot *pci_slot)
333{
334 struct hotplug_slot *slot = pci_slot->hotplug;
335 struct kobject *kobj = NULL;
336 int ret;
337
338 if (!slot || !slot->ops)
339 return;
340 kobj = kset_find_obj(module_kset, slot->mod_name);
341 if (!kobj)
342 return;
343 ret = sysfs_create_link(&pci_slot->kobj, kobj, "module");
344 if (ret)
345 dev_err(&pci_slot->bus->dev, "Error creating sysfs link (%d)\n",
346 ret);
347 kobject_put(kobj);
348}
349EXPORT_SYMBOL_GPL(pci_hp_create_module_link);
350
351/**
352 * pci_hp_remove_link - remove symbolic link to the hotplug driver module.
353 * @pci_slot: struct pci_slot
354 *
355 * Helper function for pci_hotplug_core.c to remove symbolic link to
356 * the hotplug driver module.
357 */
358void pci_hp_remove_module_link(struct pci_slot *pci_slot)
359{
360 sysfs_remove_link(&pci_slot->kobj, "module");
361}
362EXPORT_SYMBOL_GPL(pci_hp_remove_module_link);
363#endif
364
365static int pci_slot_init(void)
366{
367 struct kset *pci_bus_kset;
368
369 pci_bus_kset = bus_get_kset(&pci_bus_type);
370 pci_slots_kset = kset_create_and_add("slots", NULL,
371 &pci_bus_kset->kobj);
372 if (!pci_slots_kset) {
373 pr_err("PCI: Slot initialization failure\n");
374 return -ENOMEM;
375 }
376 return 0;
377}
378
379subsys_initcall(pci_slot_init);
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2006 Matthew Wilcox <matthew@wil.cx>
4 * Copyright (C) 2006-2009 Hewlett-Packard Development Company, L.P.
5 * Alex Chiang <achiang@hp.com>
6 */
7
8#include <linux/kobject.h>
9#include <linux/slab.h>
10#include <linux/module.h>
11#include <linux/pci.h>
12#include <linux/err.h>
13#include "pci.h"
14
15struct kset *pci_slots_kset;
16EXPORT_SYMBOL_GPL(pci_slots_kset);
17
18static ssize_t pci_slot_attr_show(struct kobject *kobj,
19 struct attribute *attr, char *buf)
20{
21 struct pci_slot *slot = to_pci_slot(kobj);
22 struct pci_slot_attribute *attribute = to_pci_slot_attr(attr);
23 return attribute->show ? attribute->show(slot, buf) : -EIO;
24}
25
26static ssize_t pci_slot_attr_store(struct kobject *kobj,
27 struct attribute *attr, const char *buf, size_t len)
28{
29 struct pci_slot *slot = to_pci_slot(kobj);
30 struct pci_slot_attribute *attribute = to_pci_slot_attr(attr);
31 return attribute->store ? attribute->store(slot, buf, len) : -EIO;
32}
33
34static const struct sysfs_ops pci_slot_sysfs_ops = {
35 .show = pci_slot_attr_show,
36 .store = pci_slot_attr_store,
37};
38
39static ssize_t address_read_file(struct pci_slot *slot, char *buf)
40{
41 if (slot->number == 0xff)
42 return sysfs_emit(buf, "%04x:%02x\n",
43 pci_domain_nr(slot->bus),
44 slot->bus->number);
45
46 return sysfs_emit(buf, "%04x:%02x:%02x\n",
47 pci_domain_nr(slot->bus),
48 slot->bus->number,
49 slot->number);
50}
51
52static ssize_t bus_speed_read(enum pci_bus_speed speed, char *buf)
53{
54 return sysfs_emit(buf, "%s\n", pci_speed_string(speed));
55}
56
57static ssize_t max_speed_read_file(struct pci_slot *slot, char *buf)
58{
59 return bus_speed_read(slot->bus->max_bus_speed, buf);
60}
61
62static ssize_t cur_speed_read_file(struct pci_slot *slot, char *buf)
63{
64 return bus_speed_read(slot->bus->cur_bus_speed, buf);
65}
66
67static void pci_slot_release(struct kobject *kobj)
68{
69 struct pci_dev *dev;
70 struct pci_slot *slot = to_pci_slot(kobj);
71
72 dev_dbg(&slot->bus->dev, "dev %02x, released physical slot %s\n",
73 slot->number, pci_slot_name(slot));
74
75 down_read(&pci_bus_sem);
76 list_for_each_entry(dev, &slot->bus->devices, bus_list)
77 if (PCI_SLOT(dev->devfn) == slot->number)
78 dev->slot = NULL;
79 up_read(&pci_bus_sem);
80
81 list_del(&slot->list);
82 pci_bus_put(slot->bus);
83
84 kfree(slot);
85}
86
87static struct pci_slot_attribute pci_slot_attr_address =
88 __ATTR(address, S_IRUGO, address_read_file, NULL);
89static struct pci_slot_attribute pci_slot_attr_max_speed =
90 __ATTR(max_bus_speed, S_IRUGO, max_speed_read_file, NULL);
91static struct pci_slot_attribute pci_slot_attr_cur_speed =
92 __ATTR(cur_bus_speed, S_IRUGO, cur_speed_read_file, NULL);
93
94static struct attribute *pci_slot_default_attrs[] = {
95 &pci_slot_attr_address.attr,
96 &pci_slot_attr_max_speed.attr,
97 &pci_slot_attr_cur_speed.attr,
98 NULL,
99};
100ATTRIBUTE_GROUPS(pci_slot_default);
101
102static const struct kobj_type pci_slot_ktype = {
103 .sysfs_ops = &pci_slot_sysfs_ops,
104 .release = &pci_slot_release,
105 .default_groups = pci_slot_default_groups,
106};
107
108static char *make_slot_name(const char *name)
109{
110 char *new_name;
111 int len, max, dup;
112
113 new_name = kstrdup(name, GFP_KERNEL);
114 if (!new_name)
115 return NULL;
116
117 /*
118 * Make sure we hit the realloc case the first time through the
119 * loop. 'len' will be strlen(name) + 3 at that point which is
120 * enough space for "name-X" and the trailing NUL.
121 */
122 len = strlen(name) + 2;
123 max = 1;
124 dup = 1;
125
126 for (;;) {
127 struct kobject *dup_slot;
128 dup_slot = kset_find_obj(pci_slots_kset, new_name);
129 if (!dup_slot)
130 break;
131 kobject_put(dup_slot);
132 if (dup == max) {
133 len++;
134 max *= 10;
135 kfree(new_name);
136 new_name = kmalloc(len, GFP_KERNEL);
137 if (!new_name)
138 break;
139 }
140 sprintf(new_name, "%s-%d", name, dup++);
141 }
142
143 return new_name;
144}
145
146static int rename_slot(struct pci_slot *slot, const char *name)
147{
148 int result = 0;
149 char *slot_name;
150
151 if (strcmp(pci_slot_name(slot), name) == 0)
152 return result;
153
154 slot_name = make_slot_name(name);
155 if (!slot_name)
156 return -ENOMEM;
157
158 result = kobject_rename(&slot->kobj, slot_name);
159 kfree(slot_name);
160
161 return result;
162}
163
164void pci_dev_assign_slot(struct pci_dev *dev)
165{
166 struct pci_slot *slot;
167
168 mutex_lock(&pci_slot_mutex);
169 list_for_each_entry(slot, &dev->bus->slots, list)
170 if (PCI_SLOT(dev->devfn) == slot->number)
171 dev->slot = slot;
172 mutex_unlock(&pci_slot_mutex);
173}
174
175static struct pci_slot *get_slot(struct pci_bus *parent, int slot_nr)
176{
177 struct pci_slot *slot;
178
179 /* We already hold pci_slot_mutex */
180 list_for_each_entry(slot, &parent->slots, list)
181 if (slot->number == slot_nr) {
182 kobject_get(&slot->kobj);
183 return slot;
184 }
185
186 return NULL;
187}
188
189/**
190 * pci_create_slot - create or increment refcount for physical PCI slot
191 * @parent: struct pci_bus of parent bridge
192 * @slot_nr: PCI_SLOT(pci_dev->devfn) or -1 for placeholder
193 * @name: user visible string presented in /sys/bus/pci/slots/<name>
194 * @hotplug: set if caller is hotplug driver, NULL otherwise
195 *
196 * PCI slots have first class attributes such as address, speed, width,
197 * and a &struct pci_slot is used to manage them. This interface will
198 * either return a new &struct pci_slot to the caller, or if the pci_slot
199 * already exists, its refcount will be incremented.
200 *
201 * Slots are uniquely identified by a @pci_bus, @slot_nr tuple.
202 *
203 * There are known platforms with broken firmware that assign the same
204 * name to multiple slots. Workaround these broken platforms by renaming
205 * the slots on behalf of the caller. If firmware assigns name N to
206 * multiple slots:
207 *
208 * The first slot is assigned N
209 * The second slot is assigned N-1
210 * The third slot is assigned N-2
211 * etc.
212 *
213 * Placeholder slots:
214 * In most cases, @pci_bus, @slot_nr will be sufficient to uniquely identify
215 * a slot. There is one notable exception - pSeries (rpaphp), where the
216 * @slot_nr cannot be determined until a device is actually inserted into
217 * the slot. In this scenario, the caller may pass -1 for @slot_nr.
218 *
219 * The following semantics are imposed when the caller passes @slot_nr ==
220 * -1. First, we no longer check for an existing %struct pci_slot, as there
221 * may be many slots with @slot_nr of -1. The other change in semantics is
222 * user-visible, which is the 'address' parameter presented in sysfs will
223 * consist solely of a dddd:bb tuple, where dddd is the PCI domain of the
224 * %struct pci_bus and bb is the bus number. In other words, the devfn of
225 * the 'placeholder' slot will not be displayed.
226 */
227struct pci_slot *pci_create_slot(struct pci_bus *parent, int slot_nr,
228 const char *name,
229 struct hotplug_slot *hotplug)
230{
231 struct pci_dev *dev;
232 struct pci_slot *slot;
233 int err = 0;
234 char *slot_name = NULL;
235
236 mutex_lock(&pci_slot_mutex);
237
238 if (slot_nr == -1)
239 goto placeholder;
240
241 /*
242 * Hotplug drivers are allowed to rename an existing slot,
243 * but only if not already claimed.
244 */
245 slot = get_slot(parent, slot_nr);
246 if (slot) {
247 if (hotplug) {
248 if (slot->hotplug) {
249 err = -EBUSY;
250 goto put_slot;
251 }
252 err = rename_slot(slot, name);
253 if (err)
254 goto put_slot;
255 }
256 goto out;
257 }
258
259placeholder:
260 slot = kzalloc(sizeof(*slot), GFP_KERNEL);
261 if (!slot) {
262 err = -ENOMEM;
263 goto err;
264 }
265
266 slot->bus = pci_bus_get(parent);
267 slot->number = slot_nr;
268
269 slot->kobj.kset = pci_slots_kset;
270
271 slot_name = make_slot_name(name);
272 if (!slot_name) {
273 err = -ENOMEM;
274 pci_bus_put(slot->bus);
275 kfree(slot);
276 goto err;
277 }
278
279 INIT_LIST_HEAD(&slot->list);
280 list_add(&slot->list, &parent->slots);
281
282 err = kobject_init_and_add(&slot->kobj, &pci_slot_ktype, NULL,
283 "%s", slot_name);
284 if (err)
285 goto put_slot;
286
287 down_read(&pci_bus_sem);
288 list_for_each_entry(dev, &parent->devices, bus_list)
289 if (PCI_SLOT(dev->devfn) == slot_nr)
290 dev->slot = slot;
291 up_read(&pci_bus_sem);
292
293 dev_dbg(&parent->dev, "dev %02x, created physical slot %s\n",
294 slot_nr, pci_slot_name(slot));
295
296out:
297 kfree(slot_name);
298 mutex_unlock(&pci_slot_mutex);
299 return slot;
300
301put_slot:
302 kobject_put(&slot->kobj);
303err:
304 slot = ERR_PTR(err);
305 goto out;
306}
307EXPORT_SYMBOL_GPL(pci_create_slot);
308
309/**
310 * pci_destroy_slot - decrement refcount for physical PCI slot
311 * @slot: struct pci_slot to decrement
312 *
313 * %struct pci_slot is refcounted, so destroying them is really easy; we
314 * just call kobject_put on its kobj and let our release methods do the
315 * rest.
316 */
317void pci_destroy_slot(struct pci_slot *slot)
318{
319 dev_dbg(&slot->bus->dev, "dev %02x, dec refcount to %d\n",
320 slot->number, kref_read(&slot->kobj.kref) - 1);
321
322 mutex_lock(&pci_slot_mutex);
323 kobject_put(&slot->kobj);
324 mutex_unlock(&pci_slot_mutex);
325}
326EXPORT_SYMBOL_GPL(pci_destroy_slot);
327
328#if defined(CONFIG_HOTPLUG_PCI) || defined(CONFIG_HOTPLUG_PCI_MODULE)
329#include <linux/pci_hotplug.h>
330/**
331 * pci_hp_create_module_link - create symbolic link to hotplug driver module
332 * @pci_slot: struct pci_slot
333 *
334 * Helper function for pci_hotplug_core.c to create symbolic link to
335 * the hotplug driver module.
336 */
337void pci_hp_create_module_link(struct pci_slot *pci_slot)
338{
339 struct hotplug_slot *slot = pci_slot->hotplug;
340 struct kobject *kobj = NULL;
341 int ret;
342
343 if (!slot || !slot->ops)
344 return;
345 kobj = kset_find_obj(module_kset, slot->mod_name);
346 if (!kobj)
347 return;
348 ret = sysfs_create_link(&pci_slot->kobj, kobj, "module");
349 if (ret)
350 dev_err(&pci_slot->bus->dev, "Error creating sysfs link (%d)\n",
351 ret);
352 kobject_put(kobj);
353}
354EXPORT_SYMBOL_GPL(pci_hp_create_module_link);
355
356/**
357 * pci_hp_remove_module_link - remove symbolic link to the hotplug driver
358 * module.
359 * @pci_slot: struct pci_slot
360 *
361 * Helper function for pci_hotplug_core.c to remove symbolic link to
362 * the hotplug driver module.
363 */
364void pci_hp_remove_module_link(struct pci_slot *pci_slot)
365{
366 sysfs_remove_link(&pci_slot->kobj, "module");
367}
368EXPORT_SYMBOL_GPL(pci_hp_remove_module_link);
369#endif
370
371static int pci_slot_init(void)
372{
373 struct kset *pci_bus_kset;
374
375 pci_bus_kset = bus_get_kset(&pci_bus_type);
376 pci_slots_kset = kset_create_and_add("slots", NULL,
377 &pci_bus_kset->kobj);
378 if (!pci_slots_kset) {
379 pr_err("PCI: Slot initialization failure\n");
380 return -ENOMEM;
381 }
382 return 0;
383}
384
385subsys_initcall(pci_slot_init);