Loading...
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright(c) 2007 - 2009 Intel Corporation. All rights reserved.
4 */
5
6/*
7 * This driver supports an interface for DCA clients and providers to meet.
8 */
9
10#include <linux/kernel.h>
11#include <linux/notifier.h>
12#include <linux/device.h>
13#include <linux/dca.h>
14#include <linux/slab.h>
15#include <linux/module.h>
16
17#define DCA_VERSION "1.12.1"
18
19MODULE_VERSION(DCA_VERSION);
20MODULE_LICENSE("GPL");
21MODULE_AUTHOR("Intel Corporation");
22
23static DEFINE_RAW_SPINLOCK(dca_lock);
24
25static LIST_HEAD(dca_domains);
26
27static BLOCKING_NOTIFIER_HEAD(dca_provider_chain);
28
29static int dca_providers_blocked;
30
31static struct pci_bus *dca_pci_rc_from_dev(struct device *dev)
32{
33 struct pci_dev *pdev = to_pci_dev(dev);
34 struct pci_bus *bus = pdev->bus;
35
36 while (bus->parent)
37 bus = bus->parent;
38
39 return bus;
40}
41
42static struct dca_domain *dca_allocate_domain(struct pci_bus *rc)
43{
44 struct dca_domain *domain;
45
46 domain = kzalloc(sizeof(*domain), GFP_NOWAIT);
47 if (!domain)
48 return NULL;
49
50 INIT_LIST_HEAD(&domain->dca_providers);
51 domain->pci_rc = rc;
52
53 return domain;
54}
55
56static void dca_free_domain(struct dca_domain *domain)
57{
58 list_del(&domain->node);
59 kfree(domain);
60}
61
62static int dca_provider_ioat_ver_3_0(struct device *dev)
63{
64 struct pci_dev *pdev = to_pci_dev(dev);
65
66 return ((pdev->vendor == PCI_VENDOR_ID_INTEL) &&
67 ((pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG0) ||
68 (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG1) ||
69 (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG2) ||
70 (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG3) ||
71 (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG4) ||
72 (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG5) ||
73 (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG6) ||
74 (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG7)));
75}
76
77static void unregister_dca_providers(void)
78{
79 struct dca_provider *dca, *_dca;
80 struct list_head unregistered_providers;
81 struct dca_domain *domain;
82 unsigned long flags;
83
84 blocking_notifier_call_chain(&dca_provider_chain,
85 DCA_PROVIDER_REMOVE, NULL);
86
87 INIT_LIST_HEAD(&unregistered_providers);
88
89 raw_spin_lock_irqsave(&dca_lock, flags);
90
91 if (list_empty(&dca_domains)) {
92 raw_spin_unlock_irqrestore(&dca_lock, flags);
93 return;
94 }
95
96 /* at this point only one domain in the list is expected */
97 domain = list_first_entry(&dca_domains, struct dca_domain, node);
98
99 list_for_each_entry_safe(dca, _dca, &domain->dca_providers, node)
100 list_move(&dca->node, &unregistered_providers);
101
102 dca_free_domain(domain);
103
104 raw_spin_unlock_irqrestore(&dca_lock, flags);
105
106 list_for_each_entry_safe(dca, _dca, &unregistered_providers, node) {
107 dca_sysfs_remove_provider(dca);
108 list_del(&dca->node);
109 }
110}
111
112static struct dca_domain *dca_find_domain(struct pci_bus *rc)
113{
114 struct dca_domain *domain;
115
116 list_for_each_entry(domain, &dca_domains, node)
117 if (domain->pci_rc == rc)
118 return domain;
119
120 return NULL;
121}
122
123static struct dca_domain *dca_get_domain(struct device *dev)
124{
125 struct pci_bus *rc;
126 struct dca_domain *domain;
127
128 rc = dca_pci_rc_from_dev(dev);
129 domain = dca_find_domain(rc);
130
131 if (!domain) {
132 if (dca_provider_ioat_ver_3_0(dev) && !list_empty(&dca_domains))
133 dca_providers_blocked = 1;
134 }
135
136 return domain;
137}
138
139static struct dca_provider *dca_find_provider_by_dev(struct device *dev)
140{
141 struct dca_provider *dca;
142 struct pci_bus *rc;
143 struct dca_domain *domain;
144
145 if (dev) {
146 rc = dca_pci_rc_from_dev(dev);
147 domain = dca_find_domain(rc);
148 if (!domain)
149 return NULL;
150 } else {
151 if (!list_empty(&dca_domains))
152 domain = list_first_entry(&dca_domains,
153 struct dca_domain,
154 node);
155 else
156 return NULL;
157 }
158
159 list_for_each_entry(dca, &domain->dca_providers, node)
160 if ((!dev) || (dca->ops->dev_managed(dca, dev)))
161 return dca;
162
163 return NULL;
164}
165
166/**
167 * dca_add_requester - add a dca client to the list
168 * @dev - the device that wants dca service
169 */
170int dca_add_requester(struct device *dev)
171{
172 struct dca_provider *dca;
173 int err, slot = -ENODEV;
174 unsigned long flags;
175 struct pci_bus *pci_rc;
176 struct dca_domain *domain;
177
178 if (!dev)
179 return -EFAULT;
180
181 raw_spin_lock_irqsave(&dca_lock, flags);
182
183 /* check if the requester has not been added already */
184 dca = dca_find_provider_by_dev(dev);
185 if (dca) {
186 raw_spin_unlock_irqrestore(&dca_lock, flags);
187 return -EEXIST;
188 }
189
190 pci_rc = dca_pci_rc_from_dev(dev);
191 domain = dca_find_domain(pci_rc);
192 if (!domain) {
193 raw_spin_unlock_irqrestore(&dca_lock, flags);
194 return -ENODEV;
195 }
196
197 list_for_each_entry(dca, &domain->dca_providers, node) {
198 slot = dca->ops->add_requester(dca, dev);
199 if (slot >= 0)
200 break;
201 }
202
203 raw_spin_unlock_irqrestore(&dca_lock, flags);
204
205 if (slot < 0)
206 return slot;
207
208 err = dca_sysfs_add_req(dca, dev, slot);
209 if (err) {
210 raw_spin_lock_irqsave(&dca_lock, flags);
211 if (dca == dca_find_provider_by_dev(dev))
212 dca->ops->remove_requester(dca, dev);
213 raw_spin_unlock_irqrestore(&dca_lock, flags);
214 return err;
215 }
216
217 return 0;
218}
219EXPORT_SYMBOL_GPL(dca_add_requester);
220
221/**
222 * dca_remove_requester - remove a dca client from the list
223 * @dev - the device that wants dca service
224 */
225int dca_remove_requester(struct device *dev)
226{
227 struct dca_provider *dca;
228 int slot;
229 unsigned long flags;
230
231 if (!dev)
232 return -EFAULT;
233
234 raw_spin_lock_irqsave(&dca_lock, flags);
235 dca = dca_find_provider_by_dev(dev);
236 if (!dca) {
237 raw_spin_unlock_irqrestore(&dca_lock, flags);
238 return -ENODEV;
239 }
240 slot = dca->ops->remove_requester(dca, dev);
241 raw_spin_unlock_irqrestore(&dca_lock, flags);
242
243 if (slot < 0)
244 return slot;
245
246 dca_sysfs_remove_req(dca, slot);
247
248 return 0;
249}
250EXPORT_SYMBOL_GPL(dca_remove_requester);
251
252/**
253 * dca_common_get_tag - return the dca tag (serves both new and old api)
254 * @dev - the device that wants dca service
255 * @cpu - the cpuid as returned by get_cpu()
256 */
257static u8 dca_common_get_tag(struct device *dev, int cpu)
258{
259 struct dca_provider *dca;
260 u8 tag;
261 unsigned long flags;
262
263 raw_spin_lock_irqsave(&dca_lock, flags);
264
265 dca = dca_find_provider_by_dev(dev);
266 if (!dca) {
267 raw_spin_unlock_irqrestore(&dca_lock, flags);
268 return -ENODEV;
269 }
270 tag = dca->ops->get_tag(dca, dev, cpu);
271
272 raw_spin_unlock_irqrestore(&dca_lock, flags);
273 return tag;
274}
275
276/**
277 * dca3_get_tag - return the dca tag to the requester device
278 * for the given cpu (new api)
279 * @dev - the device that wants dca service
280 * @cpu - the cpuid as returned by get_cpu()
281 */
282u8 dca3_get_tag(struct device *dev, int cpu)
283{
284 if (!dev)
285 return -EFAULT;
286
287 return dca_common_get_tag(dev, cpu);
288}
289EXPORT_SYMBOL_GPL(dca3_get_tag);
290
291/**
292 * dca_get_tag - return the dca tag for the given cpu (old api)
293 * @cpu - the cpuid as returned by get_cpu()
294 */
295u8 dca_get_tag(int cpu)
296{
297 struct device *dev = NULL;
298
299 return dca_common_get_tag(dev, cpu);
300}
301EXPORT_SYMBOL_GPL(dca_get_tag);
302
303/**
304 * alloc_dca_provider - get data struct for describing a dca provider
305 * @ops - pointer to struct of dca operation function pointers
306 * @priv_size - size of extra mem to be added for provider's needs
307 */
308struct dca_provider *alloc_dca_provider(const struct dca_ops *ops,
309 int priv_size)
310{
311 struct dca_provider *dca;
312 int alloc_size;
313
314 alloc_size = (sizeof(*dca) + priv_size);
315 dca = kzalloc(alloc_size, GFP_KERNEL);
316 if (!dca)
317 return NULL;
318 dca->ops = ops;
319
320 return dca;
321}
322EXPORT_SYMBOL_GPL(alloc_dca_provider);
323
324/**
325 * free_dca_provider - release the dca provider data struct
326 * @ops - pointer to struct of dca operation function pointers
327 * @priv_size - size of extra mem to be added for provider's needs
328 */
329void free_dca_provider(struct dca_provider *dca)
330{
331 kfree(dca);
332}
333EXPORT_SYMBOL_GPL(free_dca_provider);
334
335/**
336 * register_dca_provider - register a dca provider
337 * @dca - struct created by alloc_dca_provider()
338 * @dev - device providing dca services
339 */
340int register_dca_provider(struct dca_provider *dca, struct device *dev)
341{
342 int err;
343 unsigned long flags;
344 struct dca_domain *domain, *newdomain = NULL;
345
346 raw_spin_lock_irqsave(&dca_lock, flags);
347 if (dca_providers_blocked) {
348 raw_spin_unlock_irqrestore(&dca_lock, flags);
349 return -ENODEV;
350 }
351 raw_spin_unlock_irqrestore(&dca_lock, flags);
352
353 err = dca_sysfs_add_provider(dca, dev);
354 if (err)
355 return err;
356
357 raw_spin_lock_irqsave(&dca_lock, flags);
358 domain = dca_get_domain(dev);
359 if (!domain) {
360 struct pci_bus *rc;
361
362 if (dca_providers_blocked) {
363 raw_spin_unlock_irqrestore(&dca_lock, flags);
364 dca_sysfs_remove_provider(dca);
365 unregister_dca_providers();
366 return -ENODEV;
367 }
368
369 raw_spin_unlock_irqrestore(&dca_lock, flags);
370 rc = dca_pci_rc_from_dev(dev);
371 newdomain = dca_allocate_domain(rc);
372 if (!newdomain)
373 return -ENODEV;
374 raw_spin_lock_irqsave(&dca_lock, flags);
375 /* Recheck, we might have raced after dropping the lock */
376 domain = dca_get_domain(dev);
377 if (!domain) {
378 domain = newdomain;
379 newdomain = NULL;
380 list_add(&domain->node, &dca_domains);
381 }
382 }
383 list_add(&dca->node, &domain->dca_providers);
384 raw_spin_unlock_irqrestore(&dca_lock, flags);
385
386 blocking_notifier_call_chain(&dca_provider_chain,
387 DCA_PROVIDER_ADD, NULL);
388 kfree(newdomain);
389 return 0;
390}
391EXPORT_SYMBOL_GPL(register_dca_provider);
392
393/**
394 * unregister_dca_provider - remove a dca provider
395 * @dca - struct created by alloc_dca_provider()
396 */
397void unregister_dca_provider(struct dca_provider *dca, struct device *dev)
398{
399 unsigned long flags;
400 struct pci_bus *pci_rc;
401 struct dca_domain *domain;
402
403 blocking_notifier_call_chain(&dca_provider_chain,
404 DCA_PROVIDER_REMOVE, NULL);
405
406 raw_spin_lock_irqsave(&dca_lock, flags);
407
408 if (list_empty(&dca_domains)) {
409 raw_spin_unlock_irqrestore(&dca_lock, flags);
410 return;
411 }
412
413 list_del(&dca->node);
414
415 pci_rc = dca_pci_rc_from_dev(dev);
416 domain = dca_find_domain(pci_rc);
417 if (list_empty(&domain->dca_providers))
418 dca_free_domain(domain);
419
420 raw_spin_unlock_irqrestore(&dca_lock, flags);
421
422 dca_sysfs_remove_provider(dca);
423}
424EXPORT_SYMBOL_GPL(unregister_dca_provider);
425
426/**
427 * dca_register_notify - register a client's notifier callback
428 */
429void dca_register_notify(struct notifier_block *nb)
430{
431 blocking_notifier_chain_register(&dca_provider_chain, nb);
432}
433EXPORT_SYMBOL_GPL(dca_register_notify);
434
435/**
436 * dca_unregister_notify - remove a client's notifier callback
437 */
438void dca_unregister_notify(struct notifier_block *nb)
439{
440 blocking_notifier_chain_unregister(&dca_provider_chain, nb);
441}
442EXPORT_SYMBOL_GPL(dca_unregister_notify);
443
444static int __init dca_init(void)
445{
446 pr_info("dca service started, version %s\n", DCA_VERSION);
447 return dca_sysfs_init();
448}
449
450static void __exit dca_exit(void)
451{
452 dca_sysfs_exit();
453}
454
455arch_initcall(dca_init);
456module_exit(dca_exit);
457
1/*
2 * Copyright(c) 2007 - 2009 Intel Corporation. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by the Free
6 * Software Foundation; either version 2 of the License, or (at your option)
7 * any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 59
16 * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
17 *
18 * The full GNU General Public License is included in this distribution in the
19 * file called COPYING.
20 */
21
22/*
23 * This driver supports an interface for DCA clients and providers to meet.
24 */
25
26#include <linux/kernel.h>
27#include <linux/notifier.h>
28#include <linux/device.h>
29#include <linux/dca.h>
30#include <linux/slab.h>
31#include <linux/module.h>
32
33#define DCA_VERSION "1.12.1"
34
35MODULE_VERSION(DCA_VERSION);
36MODULE_LICENSE("GPL");
37MODULE_AUTHOR("Intel Corporation");
38
39static DEFINE_RAW_SPINLOCK(dca_lock);
40
41static LIST_HEAD(dca_domains);
42
43static BLOCKING_NOTIFIER_HEAD(dca_provider_chain);
44
45static int dca_providers_blocked;
46
47static struct pci_bus *dca_pci_rc_from_dev(struct device *dev)
48{
49 struct pci_dev *pdev = to_pci_dev(dev);
50 struct pci_bus *bus = pdev->bus;
51
52 while (bus->parent)
53 bus = bus->parent;
54
55 return bus;
56}
57
58static struct dca_domain *dca_allocate_domain(struct pci_bus *rc)
59{
60 struct dca_domain *domain;
61
62 domain = kzalloc(sizeof(*domain), GFP_NOWAIT);
63 if (!domain)
64 return NULL;
65
66 INIT_LIST_HEAD(&domain->dca_providers);
67 domain->pci_rc = rc;
68
69 return domain;
70}
71
72static void dca_free_domain(struct dca_domain *domain)
73{
74 list_del(&domain->node);
75 kfree(domain);
76}
77
78static int dca_provider_ioat_ver_3_0(struct device *dev)
79{
80 struct pci_dev *pdev = to_pci_dev(dev);
81
82 return ((pdev->vendor == PCI_VENDOR_ID_INTEL) &&
83 ((pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG0) ||
84 (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG1) ||
85 (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG2) ||
86 (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG3) ||
87 (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG4) ||
88 (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG5) ||
89 (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG6) ||
90 (pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG7)));
91}
92
93static void unregister_dca_providers(void)
94{
95 struct dca_provider *dca, *_dca;
96 struct list_head unregistered_providers;
97 struct dca_domain *domain;
98 unsigned long flags;
99
100 blocking_notifier_call_chain(&dca_provider_chain,
101 DCA_PROVIDER_REMOVE, NULL);
102
103 INIT_LIST_HEAD(&unregistered_providers);
104
105 raw_spin_lock_irqsave(&dca_lock, flags);
106
107 if (list_empty(&dca_domains)) {
108 raw_spin_unlock_irqrestore(&dca_lock, flags);
109 return;
110 }
111
112 /* at this point only one domain in the list is expected */
113 domain = list_first_entry(&dca_domains, struct dca_domain, node);
114
115 list_for_each_entry_safe(dca, _dca, &domain->dca_providers, node)
116 list_move(&dca->node, &unregistered_providers);
117
118 dca_free_domain(domain);
119
120 raw_spin_unlock_irqrestore(&dca_lock, flags);
121
122 list_for_each_entry_safe(dca, _dca, &unregistered_providers, node) {
123 dca_sysfs_remove_provider(dca);
124 list_del(&dca->node);
125 }
126}
127
128static struct dca_domain *dca_find_domain(struct pci_bus *rc)
129{
130 struct dca_domain *domain;
131
132 list_for_each_entry(domain, &dca_domains, node)
133 if (domain->pci_rc == rc)
134 return domain;
135
136 return NULL;
137}
138
139static struct dca_domain *dca_get_domain(struct device *dev)
140{
141 struct pci_bus *rc;
142 struct dca_domain *domain;
143
144 rc = dca_pci_rc_from_dev(dev);
145 domain = dca_find_domain(rc);
146
147 if (!domain) {
148 if (dca_provider_ioat_ver_3_0(dev) && !list_empty(&dca_domains))
149 dca_providers_blocked = 1;
150 }
151
152 return domain;
153}
154
155static struct dca_provider *dca_find_provider_by_dev(struct device *dev)
156{
157 struct dca_provider *dca;
158 struct pci_bus *rc;
159 struct dca_domain *domain;
160
161 if (dev) {
162 rc = dca_pci_rc_from_dev(dev);
163 domain = dca_find_domain(rc);
164 if (!domain)
165 return NULL;
166 } else {
167 if (!list_empty(&dca_domains))
168 domain = list_first_entry(&dca_domains,
169 struct dca_domain,
170 node);
171 else
172 return NULL;
173 }
174
175 list_for_each_entry(dca, &domain->dca_providers, node)
176 if ((!dev) || (dca->ops->dev_managed(dca, dev)))
177 return dca;
178
179 return NULL;
180}
181
182/**
183 * dca_add_requester - add a dca client to the list
184 * @dev - the device that wants dca service
185 */
186int dca_add_requester(struct device *dev)
187{
188 struct dca_provider *dca;
189 int err, slot = -ENODEV;
190 unsigned long flags;
191 struct pci_bus *pci_rc;
192 struct dca_domain *domain;
193
194 if (!dev)
195 return -EFAULT;
196
197 raw_spin_lock_irqsave(&dca_lock, flags);
198
199 /* check if the requester has not been added already */
200 dca = dca_find_provider_by_dev(dev);
201 if (dca) {
202 raw_spin_unlock_irqrestore(&dca_lock, flags);
203 return -EEXIST;
204 }
205
206 pci_rc = dca_pci_rc_from_dev(dev);
207 domain = dca_find_domain(pci_rc);
208 if (!domain) {
209 raw_spin_unlock_irqrestore(&dca_lock, flags);
210 return -ENODEV;
211 }
212
213 list_for_each_entry(dca, &domain->dca_providers, node) {
214 slot = dca->ops->add_requester(dca, dev);
215 if (slot >= 0)
216 break;
217 }
218
219 raw_spin_unlock_irqrestore(&dca_lock, flags);
220
221 if (slot < 0)
222 return slot;
223
224 err = dca_sysfs_add_req(dca, dev, slot);
225 if (err) {
226 raw_spin_lock_irqsave(&dca_lock, flags);
227 if (dca == dca_find_provider_by_dev(dev))
228 dca->ops->remove_requester(dca, dev);
229 raw_spin_unlock_irqrestore(&dca_lock, flags);
230 return err;
231 }
232
233 return 0;
234}
235EXPORT_SYMBOL_GPL(dca_add_requester);
236
237/**
238 * dca_remove_requester - remove a dca client from the list
239 * @dev - the device that wants dca service
240 */
241int dca_remove_requester(struct device *dev)
242{
243 struct dca_provider *dca;
244 int slot;
245 unsigned long flags;
246
247 if (!dev)
248 return -EFAULT;
249
250 raw_spin_lock_irqsave(&dca_lock, flags);
251 dca = dca_find_provider_by_dev(dev);
252 if (!dca) {
253 raw_spin_unlock_irqrestore(&dca_lock, flags);
254 return -ENODEV;
255 }
256 slot = dca->ops->remove_requester(dca, dev);
257 raw_spin_unlock_irqrestore(&dca_lock, flags);
258
259 if (slot < 0)
260 return slot;
261
262 dca_sysfs_remove_req(dca, slot);
263
264 return 0;
265}
266EXPORT_SYMBOL_GPL(dca_remove_requester);
267
268/**
269 * dca_common_get_tag - return the dca tag (serves both new and old api)
270 * @dev - the device that wants dca service
271 * @cpu - the cpuid as returned by get_cpu()
272 */
273u8 dca_common_get_tag(struct device *dev, int cpu)
274{
275 struct dca_provider *dca;
276 u8 tag;
277 unsigned long flags;
278
279 raw_spin_lock_irqsave(&dca_lock, flags);
280
281 dca = dca_find_provider_by_dev(dev);
282 if (!dca) {
283 raw_spin_unlock_irqrestore(&dca_lock, flags);
284 return -ENODEV;
285 }
286 tag = dca->ops->get_tag(dca, dev, cpu);
287
288 raw_spin_unlock_irqrestore(&dca_lock, flags);
289 return tag;
290}
291
292/**
293 * dca3_get_tag - return the dca tag to the requester device
294 * for the given cpu (new api)
295 * @dev - the device that wants dca service
296 * @cpu - the cpuid as returned by get_cpu()
297 */
298u8 dca3_get_tag(struct device *dev, int cpu)
299{
300 if (!dev)
301 return -EFAULT;
302
303 return dca_common_get_tag(dev, cpu);
304}
305EXPORT_SYMBOL_GPL(dca3_get_tag);
306
307/**
308 * dca_get_tag - return the dca tag for the given cpu (old api)
309 * @cpu - the cpuid as returned by get_cpu()
310 */
311u8 dca_get_tag(int cpu)
312{
313 struct device *dev = NULL;
314
315 return dca_common_get_tag(dev, cpu);
316}
317EXPORT_SYMBOL_GPL(dca_get_tag);
318
319/**
320 * alloc_dca_provider - get data struct for describing a dca provider
321 * @ops - pointer to struct of dca operation function pointers
322 * @priv_size - size of extra mem to be added for provider's needs
323 */
324struct dca_provider *alloc_dca_provider(struct dca_ops *ops, int priv_size)
325{
326 struct dca_provider *dca;
327 int alloc_size;
328
329 alloc_size = (sizeof(*dca) + priv_size);
330 dca = kzalloc(alloc_size, GFP_KERNEL);
331 if (!dca)
332 return NULL;
333 dca->ops = ops;
334
335 return dca;
336}
337EXPORT_SYMBOL_GPL(alloc_dca_provider);
338
339/**
340 * free_dca_provider - release the dca provider data struct
341 * @ops - pointer to struct of dca operation function pointers
342 * @priv_size - size of extra mem to be added for provider's needs
343 */
344void free_dca_provider(struct dca_provider *dca)
345{
346 kfree(dca);
347}
348EXPORT_SYMBOL_GPL(free_dca_provider);
349
350/**
351 * register_dca_provider - register a dca provider
352 * @dca - struct created by alloc_dca_provider()
353 * @dev - device providing dca services
354 */
355int register_dca_provider(struct dca_provider *dca, struct device *dev)
356{
357 int err;
358 unsigned long flags;
359 struct dca_domain *domain, *newdomain = NULL;
360
361 raw_spin_lock_irqsave(&dca_lock, flags);
362 if (dca_providers_blocked) {
363 raw_spin_unlock_irqrestore(&dca_lock, flags);
364 return -ENODEV;
365 }
366 raw_spin_unlock_irqrestore(&dca_lock, flags);
367
368 err = dca_sysfs_add_provider(dca, dev);
369 if (err)
370 return err;
371
372 raw_spin_lock_irqsave(&dca_lock, flags);
373 domain = dca_get_domain(dev);
374 if (!domain) {
375 struct pci_bus *rc;
376
377 if (dca_providers_blocked) {
378 raw_spin_unlock_irqrestore(&dca_lock, flags);
379 dca_sysfs_remove_provider(dca);
380 unregister_dca_providers();
381 return -ENODEV;
382 }
383
384 raw_spin_unlock_irqrestore(&dca_lock, flags);
385 rc = dca_pci_rc_from_dev(dev);
386 newdomain = dca_allocate_domain(rc);
387 if (!newdomain)
388 return -ENODEV;
389 raw_spin_lock_irqsave(&dca_lock, flags);
390 /* Recheck, we might have raced after dropping the lock */
391 domain = dca_get_domain(dev);
392 if (!domain) {
393 domain = newdomain;
394 newdomain = NULL;
395 list_add(&domain->node, &dca_domains);
396 }
397 }
398 list_add(&dca->node, &domain->dca_providers);
399 raw_spin_unlock_irqrestore(&dca_lock, flags);
400
401 blocking_notifier_call_chain(&dca_provider_chain,
402 DCA_PROVIDER_ADD, NULL);
403 kfree(newdomain);
404 return 0;
405}
406EXPORT_SYMBOL_GPL(register_dca_provider);
407
408/**
409 * unregister_dca_provider - remove a dca provider
410 * @dca - struct created by alloc_dca_provider()
411 */
412void unregister_dca_provider(struct dca_provider *dca, struct device *dev)
413{
414 unsigned long flags;
415 struct pci_bus *pci_rc;
416 struct dca_domain *domain;
417
418 blocking_notifier_call_chain(&dca_provider_chain,
419 DCA_PROVIDER_REMOVE, NULL);
420
421 raw_spin_lock_irqsave(&dca_lock, flags);
422
423 list_del(&dca->node);
424
425 pci_rc = dca_pci_rc_from_dev(dev);
426 domain = dca_find_domain(pci_rc);
427 if (list_empty(&domain->dca_providers))
428 dca_free_domain(domain);
429
430 raw_spin_unlock_irqrestore(&dca_lock, flags);
431
432 dca_sysfs_remove_provider(dca);
433}
434EXPORT_SYMBOL_GPL(unregister_dca_provider);
435
436/**
437 * dca_register_notify - register a client's notifier callback
438 */
439void dca_register_notify(struct notifier_block *nb)
440{
441 blocking_notifier_chain_register(&dca_provider_chain, nb);
442}
443EXPORT_SYMBOL_GPL(dca_register_notify);
444
445/**
446 * dca_unregister_notify - remove a client's notifier callback
447 */
448void dca_unregister_notify(struct notifier_block *nb)
449{
450 blocking_notifier_chain_unregister(&dca_provider_chain, nb);
451}
452EXPORT_SYMBOL_GPL(dca_unregister_notify);
453
454static int __init dca_init(void)
455{
456 pr_info("dca service started, version %s\n", DCA_VERSION);
457 return dca_sysfs_init();
458}
459
460static void __exit dca_exit(void)
461{
462 dca_sysfs_exit();
463}
464
465arch_initcall(dca_init);
466module_exit(dca_exit);
467