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