aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/pci/hotplug/fakephp.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/pci/hotplug/fakephp.c')
-rw-r--r--drivers/pci/hotplug/fakephp.c444
1 files changed, 106 insertions, 338 deletions
diff --git a/drivers/pci/hotplug/fakephp.c b/drivers/pci/hotplug/fakephp.c
index d8649e127298..6151389fd903 100644
--- a/drivers/pci/hotplug/fakephp.c
+++ b/drivers/pci/hotplug/fakephp.c
@@ -1,395 +1,163 @@
1/* 1/* Works like the fakephp driver used to, except a little better.
2 * Fake PCI Hot Plug Controller Driver
3 * 2 *
4 * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com> 3 * - It's possible to remove devices with subordinate busses.
5 * Copyright (C) 2003 IBM Corp. 4 * - New PCI devices that appear via any method, not just a fakephp triggered
6 * Copyright (C) 2003 Rolf Eike Beer <eike-kernel@sf-tec.de> 5 * rescan, will be noticed.
6 * - Devices that are removed via any method, not just a fakephp triggered
7 * removal, will also be noticed.
7 * 8 *
8 * Based on ideas and code from: 9 * Uses nothing from the pci-hotplug subsystem.
9 * Vladimir Kondratiev <vladimir.kondratiev@intel.com>
10 * Rolf Eike Beer <eike-kernel@sf-tec.de>
11 * 10 *
12 * All rights reserved.
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation, version 2 of the License.
17 *
18 * Send feedback to <greg@kroah.com>
19 */ 11 */
20 12
21/*
22 *
23 * This driver will "emulate" removing PCI devices from the system. If
24 * the "power" file is written to with "0" then the specified PCI device
25 * will be completely removed from the kernel.
26 *
27 * WARNING, this does NOT turn off the power to the PCI device. This is
28 * a "logical" removal, not a physical or electrical removal.
29 *
30 * Use this module at your own risk, you have been warned!
31 *
32 * Enabling PCI devices is left as an exercise for the reader...
33 *
34 */
35#include <linux/kernel.h>
36#include <linux/module.h> 13#include <linux/module.h>
37#include <linux/pci.h> 14#include <linux/kernel.h>
38#include <linux/pci_hotplug.h> 15#include <linux/types.h>
16#include <linux/list.h>
17#include <linux/kobject.h>
18#include <linux/sysfs.h>
39#include <linux/init.h> 19#include <linux/init.h>
40#include <linux/string.h> 20#include <linux/pci.h>
41#include <linux/slab.h> 21#include <linux/device.h>
42#include <linux/workqueue.h>
43#include "../pci.h" 22#include "../pci.h"
44 23
45#if !defined(MODULE) 24struct legacy_slot {
46 #define MY_NAME "fakephp" 25 struct kobject kobj;
47#else 26 struct pci_dev *dev;
48 #define MY_NAME THIS_MODULE->name 27 struct list_head list;
49#endif
50
51#define dbg(format, arg...) \
52 do { \
53 if (debug) \
54 printk(KERN_DEBUG "%s: " format, \
55 MY_NAME , ## arg); \
56 } while (0)
57#define err(format, arg...) printk(KERN_ERR "%s: " format, MY_NAME , ## arg)
58#define info(format, arg...) printk(KERN_INFO "%s: " format, MY_NAME , ## arg)
59
60#define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>"
61#define DRIVER_DESC "Fake PCI Hot Plug Controller Driver"
62
63struct dummy_slot {
64 struct list_head node;
65 struct hotplug_slot *slot;
66 struct pci_dev *dev;
67 struct work_struct remove_work;
68 unsigned long removed;
69}; 28};
70 29
71static int debug; 30static LIST_HEAD(legacy_list);
72static int dup_slots;
73static LIST_HEAD(slot_list);
74static struct workqueue_struct *dummyphp_wq;
75
76static void pci_rescan_worker(struct work_struct *work);
77static DECLARE_WORK(pci_rescan_work, pci_rescan_worker);
78
79static int enable_slot (struct hotplug_slot *slot);
80static int disable_slot (struct hotplug_slot *slot);
81 31
82static struct hotplug_slot_ops dummy_hotplug_slot_ops = { 32static ssize_t legacy_show(struct kobject *kobj, struct attribute *attr,
83 .owner = THIS_MODULE, 33 char *buf)
84 .enable_slot = enable_slot,
85 .disable_slot = disable_slot,
86};
87
88static void dummy_release(struct hotplug_slot *slot)
89{ 34{
90 struct dummy_slot *dslot = slot->private; 35 struct legacy_slot *slot = container_of(kobj, typeof(*slot), kobj);
91 36 strcpy(buf, "1\n");
92 list_del(&dslot->node); 37 return 2;
93 kfree(dslot->slot->info);
94 kfree(dslot->slot);
95 pci_dev_put(dslot->dev);
96 kfree(dslot);
97} 38}
98 39
99#define SLOT_NAME_SIZE 8 40static void remove_callback(void *data)
100
101static int add_slot(struct pci_dev *dev)
102{ 41{
103 struct dummy_slot *dslot; 42 pci_remove_bus_device((struct pci_dev *)data);
104 struct hotplug_slot *slot;
105 char name[SLOT_NAME_SIZE];
106 int retval = -ENOMEM;
107 static int count = 1;
108
109 slot = kzalloc(sizeof(struct hotplug_slot), GFP_KERNEL);
110 if (!slot)
111 goto error;
112
113 slot->info = kzalloc(sizeof(struct hotplug_slot_info), GFP_KERNEL);
114 if (!slot->info)
115 goto error_slot;
116
117 slot->info->power_status = 1;
118 slot->info->max_bus_speed = PCI_SPEED_UNKNOWN;
119 slot->info->cur_bus_speed = PCI_SPEED_UNKNOWN;
120
121 dslot = kzalloc(sizeof(struct dummy_slot), GFP_KERNEL);
122 if (!dslot)
123 goto error_info;
124
125 if (dup_slots)
126 snprintf(name, SLOT_NAME_SIZE, "fake");
127 else
128 snprintf(name, SLOT_NAME_SIZE, "fake%d", count++);
129 dbg("slot->name = %s\n", name);
130 slot->ops = &dummy_hotplug_slot_ops;
131 slot->release = &dummy_release;
132 slot->private = dslot;
133
134 retval = pci_hp_register(slot, dev->bus, PCI_SLOT(dev->devfn), name);
135 if (retval) {
136 err("pci_hp_register failed with error %d\n", retval);
137 goto error_dslot;
138 }
139
140 dbg("slot->name = %s\n", hotplug_slot_name(slot));
141 dslot->slot = slot;
142 dslot->dev = pci_dev_get(dev);
143 list_add (&dslot->node, &slot_list);
144 return retval;
145
146error_dslot:
147 kfree(dslot);
148error_info:
149 kfree(slot->info);
150error_slot:
151 kfree(slot);
152error:
153 return retval;
154} 43}
155 44
156static int __init pci_scan_buses(void) 45static ssize_t legacy_store(struct kobject *kobj, struct attribute *attr,
46 const char *buf, size_t len)
157{ 47{
158 struct pci_dev *dev = NULL; 48 struct legacy_slot *slot = container_of(kobj, typeof(*slot), kobj);
159 int lastslot = 0; 49 unsigned long val;
160 50
161 while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) { 51 if (strict_strtoul(buf, 0, &val) < 0)
162 if (PCI_FUNC(dev->devfn) > 0 && 52 return -EINVAL;
163 lastslot == PCI_SLOT(dev->devfn))
164 continue;
165 lastslot = PCI_SLOT(dev->devfn);
166 add_slot(dev);
167 }
168 53
169 return 0; 54 if (val)
55 pci_rescan_bus(slot->dev->bus);
56 else
57 sysfs_schedule_callback(&slot->dev->dev.kobj, remove_callback,
58 slot->dev, THIS_MODULE);
59 return len;
170} 60}
171 61
172static void remove_slot(struct dummy_slot *dslot) 62static struct attribute *legacy_attrs[] = {
173{ 63 &(struct attribute){ .name = "power", .mode = 0644 },
174 int retval; 64 NULL,
175 65};
176 dbg("removing slot %s\n", hotplug_slot_name(dslot->slot));
177 retval = pci_hp_deregister(dslot->slot);
178 if (retval)
179 err("Problem unregistering a slot %s\n",
180 hotplug_slot_name(dslot->slot));
181}
182 66
183/* called from the single-threaded workqueue handler to remove a slot */ 67static void legacy_release(struct kobject *kobj)
184static void remove_slot_worker(struct work_struct *work)
185{ 68{
186 struct dummy_slot *dslot = 69 struct legacy_slot *slot = container_of(kobj, typeof(*slot), kobj);
187 container_of(work, struct dummy_slot, remove_work);
188 remove_slot(dslot);
189}
190 70
191/** 71 pci_dev_put(slot->dev);
192 * pci_rescan_slot - Rescan slot 72 kfree(slot);
193 * @temp: Device template. Should be set: bus and devfn.
194 *
195 * Tries hard not to re-enable already existing devices;
196 * also handles scanning of subfunctions.
197 */
198static int pci_rescan_slot(struct pci_dev *temp)
199{
200 struct pci_bus *bus = temp->bus;
201 struct pci_dev *dev;
202 int func;
203 u8 hdr_type;
204 int count = 0;
205
206 if (!pci_read_config_byte(temp, PCI_HEADER_TYPE, &hdr_type)) {
207 temp->hdr_type = hdr_type & 0x7f;
208 if ((dev = pci_get_slot(bus, temp->devfn)) != NULL)
209 pci_dev_put(dev);
210 else {
211 dev = pci_scan_single_device(bus, temp->devfn);
212 if (dev) {
213 dbg("New device on %s function %x:%x\n",
214 bus->name, temp->devfn >> 3,
215 temp->devfn & 7);
216 count++;
217 }
218 }
219 /* multifunction device? */
220 if (!(hdr_type & 0x80))
221 return count;
222
223 /* continue scanning for other functions */
224 for (func = 1, temp->devfn++; func < 8; func++, temp->devfn++) {
225 if (pci_read_config_byte(temp, PCI_HEADER_TYPE, &hdr_type))
226 continue;
227 temp->hdr_type = hdr_type & 0x7f;
228
229 if ((dev = pci_get_slot(bus, temp->devfn)) != NULL)
230 pci_dev_put(dev);
231 else {
232 dev = pci_scan_single_device(bus, temp->devfn);
233 if (dev) {
234 dbg("New device on %s function %x:%x\n",
235 bus->name, temp->devfn >> 3,
236 temp->devfn & 7);
237 count++;
238 }
239 }
240 }
241 }
242
243 return count;
244} 73}
245 74
75static struct kobj_type legacy_ktype = {
76 .sysfs_ops = &(struct sysfs_ops){
77 .store = legacy_store, .show = legacy_show
78 },
79 .release = &legacy_release,
80 .default_attrs = legacy_attrs,
81};
246 82
247/** 83static int legacy_add_slot(struct pci_dev *pdev)
248 * pci_rescan_bus - Rescan PCI bus
249 * @bus: the PCI bus to rescan
250 *
251 * Call pci_rescan_slot for each possible function of the bus.
252 */
253static void pci_rescan_bus(const struct pci_bus *bus)
254{ 84{
255 unsigned int devfn; 85 struct legacy_slot *slot = kzalloc(sizeof(*slot), GFP_KERNEL);
256 struct pci_dev *dev;
257 int retval;
258 int found = 0;
259 dev = alloc_pci_dev();
260 if (!dev)
261 return;
262 86
263 dev->bus = (struct pci_bus*)bus; 87 if (!slot)
264 dev->sysdata = bus->sysdata; 88 return -ENOMEM;
265 for (devfn = 0; devfn < 0x100; devfn += 8) {
266 dev->devfn = devfn;
267 found += pci_rescan_slot(dev);
268 }
269
270 if (found) {
271 pci_bus_assign_resources(bus);
272 list_for_each_entry(dev, &bus->devices, bus_list) {
273 /* Skip already-added devices */
274 if (dev->is_added)
275 continue;
276 retval = pci_bus_add_device(dev);
277 if (retval)
278 dev_err(&dev->dev,
279 "Error adding device, continuing\n");
280 else
281 add_slot(dev);
282 }
283 pci_bus_add_devices(bus);
284 }
285 kfree(dev);
286}
287 89
288/* recursively scan all buses */ 90 if (kobject_init_and_add(&slot->kobj, &legacy_ktype,
289static void pci_rescan_buses(const struct list_head *list) 91 &pci_slots_kset->kobj, "%s",
290{ 92 dev_name(&pdev->dev))) {
291 const struct list_head *l; 93 dev_warn(&pdev->dev, "Failed to created legacy fake slot\n");
292 list_for_each(l,list) { 94 return -EINVAL;
293 const struct pci_bus *b = pci_bus_b(l);
294 pci_rescan_bus(b);
295 pci_rescan_buses(&b->children);
296 } 95 }
297} 96 slot->dev = pci_dev_get(pdev);
298 97
299/* initiate rescan of all pci buses */ 98 list_add(&slot->list, &legacy_list);
300static inline void pci_rescan(void) {
301 pci_rescan_buses(&pci_root_buses);
302}
303
304/* called from the single-threaded workqueue handler to rescan all pci buses */
305static void pci_rescan_worker(struct work_struct *work)
306{
307 pci_rescan();
308}
309 99
310static int enable_slot(struct hotplug_slot *hotplug_slot)
311{
312 /* mis-use enable_slot for rescanning of the pci bus */
313 cancel_work_sync(&pci_rescan_work);
314 queue_work(dummyphp_wq, &pci_rescan_work);
315 return 0; 100 return 0;
316} 101}
317 102
318static int disable_slot(struct hotplug_slot *slot) 103static int legacy_notify(struct notifier_block *nb,
104 unsigned long action, void *data)
319{ 105{
320 struct dummy_slot *dslot; 106 struct pci_dev *pdev = to_pci_dev(data);
321 struct pci_dev *dev;
322 int func;
323
324 if (!slot)
325 return -ENODEV;
326 dslot = slot->private;
327
328 dbg("%s - physical_slot = %s\n", __func__, hotplug_slot_name(slot));
329 107
330 for (func = 7; func >= 0; func--) { 108 if (action == BUS_NOTIFY_ADD_DEVICE) {
331 dev = pci_get_slot(dslot->dev->bus, dslot->dev->devfn + func); 109 legacy_add_slot(pdev);
332 if (!dev) 110 } else if (action == BUS_NOTIFY_DEL_DEVICE) {
333 continue; 111 struct legacy_slot *slot;
334 112
335 if (test_and_set_bit(0, &dslot->removed)) { 113 list_for_each_entry(slot, &legacy_list, list)
336 dbg("Slot already scheduled for removal\n"); 114 if (slot->dev == pdev)
337 pci_dev_put(dev); 115 goto found;
338 return -ENODEV;
339 }
340 116
341 /* remove the device from the pci core */ 117 dev_warn(&pdev->dev, "Missing legacy fake slot?");
342 pci_remove_bus_device(dev); 118 return -ENODEV;
343 119found:
344 /* queue work item to blow away this sysfs entry and other 120 kobject_del(&slot->kobj);
345 * parts. 121 list_del(&slot->list);
346 */ 122 kobject_put(&slot->kobj);
347 INIT_WORK(&dslot->remove_work, remove_slot_worker);
348 queue_work(dummyphp_wq, &dslot->remove_work);
349
350 pci_dev_put(dev);
351 } 123 }
124
352 return 0; 125 return 0;
353} 126}
354 127
355static void cleanup_slots (void) 128static struct notifier_block legacy_notifier = {
356{ 129 .notifier_call = legacy_notify
357 struct list_head *tmp; 130};
358 struct list_head *next;
359 struct dummy_slot *dslot;
360
361 destroy_workqueue(dummyphp_wq);
362 list_for_each_safe (tmp, next, &slot_list) {
363 dslot = list_entry (tmp, struct dummy_slot, node);
364 remove_slot(dslot);
365 }
366
367}
368 131
369static int __init dummyphp_init(void) 132static int __init init_legacy(void)
370{ 133{
371 info(DRIVER_DESC "\n"); 134 struct pci_dev *pdev = NULL;
372 135
373 dummyphp_wq = create_singlethread_workqueue(MY_NAME); 136 /* Add existing devices */
374 if (!dummyphp_wq) 137 while ((pdev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, pdev)))
375 return -ENOMEM; 138 legacy_add_slot(pdev);
376 139
377 return pci_scan_buses(); 140 /* Be alerted of any new ones */
141 bus_register_notifier(&pci_bus_type, &legacy_notifier);
142 return 0;
378} 143}
144module_init(init_legacy);
379 145
380 146static void __exit remove_legacy(void)
381static void __exit dummyphp_exit(void)
382{ 147{
383 cleanup_slots(); 148 struct legacy_slot *slot, *tmp;
149
150 bus_unregister_notifier(&pci_bus_type, &legacy_notifier);
151
152 list_for_each_entry_safe(slot, tmp, &legacy_list, list) {
153 list_del(&slot->list);
154 kobject_del(&slot->kobj);
155 kobject_put(&slot->kobj);
156 }
384} 157}
158module_exit(remove_legacy);
385 159
386module_init(dummyphp_init);
387module_exit(dummyphp_exit);
388 160
389MODULE_AUTHOR(DRIVER_AUTHOR); 161MODULE_AUTHOR("Trent Piepho <xyzzy@speakeasy.org>");
390MODULE_DESCRIPTION(DRIVER_DESC); 162MODULE_DESCRIPTION("Legacy version of the fakephp interface");
391MODULE_LICENSE("GPL"); 163MODULE_LICENSE("GPL");
392module_param(debug, bool, S_IRUGO | S_IWUSR);
393MODULE_PARM_DESC(debug, "Debugging mode enabled or not");
394module_param(dup_slots, bool, S_IRUGO | S_IWUSR);
395MODULE_PARM_DESC(dup_slots, "Force duplicate slot names for debugging");
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-24 19:33:34 -0500