Commit | Line | Data |
---|---|---|
7589670f | 1 | /* |
211a22ce | 2 | * Copyright(c) 2007 - 2009 Intel Corporation. All rights reserved. |
7589670f SN |
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> | |
5a0e3ad6 | 30 | #include <linux/slab.h> |
7589670f | 31 | |
1a5aeeec | 32 | #define DCA_VERSION "1.12.1" |
7589670f | 33 | |
7f1b358a MS |
34 | MODULE_VERSION(DCA_VERSION); |
35 | MODULE_LICENSE("GPL"); | |
36 | MODULE_AUTHOR("Intel Corporation"); | |
7589670f SN |
37 | |
38 | static DEFINE_SPINLOCK(dca_lock); | |
39 | ||
1a5aeeec | 40 | static LIST_HEAD(dca_domains); |
7f1b358a | 41 | |
1a5aeeec | 42 | static struct pci_bus *dca_pci_rc_from_dev(struct device *dev) |
7f1b358a | 43 | { |
1a5aeeec MS |
44 | struct pci_dev *pdev = to_pci_dev(dev); |
45 | struct pci_bus *bus = pdev->bus; | |
7f1b358a | 46 | |
1a5aeeec MS |
47 | while (bus->parent) |
48 | bus = bus->parent; | |
49 | ||
50 | return bus; | |
51 | } | |
52 | ||
53 | static struct dca_domain *dca_allocate_domain(struct pci_bus *rc) | |
54 | { | |
55 | struct dca_domain *domain; | |
56 | ||
57 | domain = kzalloc(sizeof(*domain), GFP_NOWAIT); | |
58 | if (!domain) | |
59 | return NULL; | |
60 | ||
61 | INIT_LIST_HEAD(&domain->dca_providers); | |
62 | domain->pci_rc = rc; | |
63 | ||
64 | return domain; | |
65 | } | |
66 | ||
67 | static void dca_free_domain(struct dca_domain *domain) | |
68 | { | |
69 | list_del(&domain->node); | |
70 | kfree(domain); | |
71 | } | |
72 | ||
73 | static struct dca_domain *dca_find_domain(struct pci_bus *rc) | |
74 | { | |
75 | struct dca_domain *domain; | |
76 | ||
77 | list_for_each_entry(domain, &dca_domains, node) | |
78 | if (domain->pci_rc == rc) | |
79 | return domain; | |
80 | ||
81 | return NULL; | |
82 | } | |
83 | ||
84 | static struct dca_domain *dca_get_domain(struct device *dev) | |
85 | { | |
86 | struct pci_bus *rc; | |
87 | struct dca_domain *domain; | |
88 | ||
89 | rc = dca_pci_rc_from_dev(dev); | |
90 | domain = dca_find_domain(rc); | |
91 | ||
92 | if (!domain) { | |
93 | domain = dca_allocate_domain(rc); | |
94 | if (domain) | |
95 | list_add(&domain->node, &dca_domains); | |
96 | } | |
97 | ||
98 | return domain; | |
99 | } | |
100 | ||
101 | static struct dca_provider *dca_find_provider_by_dev(struct device *dev) | |
102 | { | |
103 | struct dca_provider *dca; | |
104 | struct pci_bus *rc; | |
105 | struct dca_domain *domain; | |
106 | ||
107 | if (dev) { | |
108 | rc = dca_pci_rc_from_dev(dev); | |
109 | domain = dca_find_domain(rc); | |
110 | if (!domain) | |
111 | return NULL; | |
112 | } else { | |
113 | if (!list_empty(&dca_domains)) | |
114 | domain = list_first_entry(&dca_domains, | |
115 | struct dca_domain, | |
116 | node); | |
117 | else | |
118 | return NULL; | |
7f1b358a MS |
119 | } |
120 | ||
1a5aeeec MS |
121 | list_for_each_entry(dca, &domain->dca_providers, node) |
122 | if ((!dev) || (dca->ops->dev_managed(dca, dev))) | |
123 | return dca; | |
124 | ||
125 | return NULL; | |
7f1b358a | 126 | } |
7589670f SN |
127 | |
128 | /** | |
129 | * dca_add_requester - add a dca client to the list | |
130 | * @dev - the device that wants dca service | |
131 | */ | |
132 | int dca_add_requester(struct device *dev) | |
133 | { | |
7f1b358a MS |
134 | struct dca_provider *dca; |
135 | int err, slot = -ENODEV; | |
eb4400e3 | 136 | unsigned long flags; |
1a5aeeec MS |
137 | struct pci_bus *pci_rc; |
138 | struct dca_domain *domain; | |
7589670f | 139 | |
7f1b358a MS |
140 | if (!dev) |
141 | return -EFAULT; | |
7589670f | 142 | |
eb4400e3 | 143 | spin_lock_irqsave(&dca_lock, flags); |
7f1b358a MS |
144 | |
145 | /* check if the requester has not been added already */ | |
146 | dca = dca_find_provider_by_dev(dev); | |
147 | if (dca) { | |
eb4400e3 | 148 | spin_unlock_irqrestore(&dca_lock, flags); |
7f1b358a MS |
149 | return -EEXIST; |
150 | } | |
151 | ||
1a5aeeec MS |
152 | pci_rc = dca_pci_rc_from_dev(dev); |
153 | domain = dca_find_domain(pci_rc); | |
154 | if (!domain) { | |
155 | spin_unlock_irqrestore(&dca_lock, flags); | |
156 | return -ENODEV; | |
157 | } | |
158 | ||
159 | list_for_each_entry(dca, &domain->dca_providers, node) { | |
7f1b358a MS |
160 | slot = dca->ops->add_requester(dca, dev); |
161 | if (slot >= 0) | |
162 | break; | |
163 | } | |
eb4400e3 MS |
164 | |
165 | spin_unlock_irqrestore(&dca_lock, flags); | |
166 | ||
167 | if (slot < 0) | |
7589670f SN |
168 | return slot; |
169 | ||
7f1b358a | 170 | err = dca_sysfs_add_req(dca, dev, slot); |
7589670f | 171 | if (err) { |
eb4400e3 MS |
172 | spin_lock_irqsave(&dca_lock, flags); |
173 | if (dca == dca_find_provider_by_dev(dev)) | |
174 | dca->ops->remove_requester(dca, dev); | |
175 | spin_unlock_irqrestore(&dca_lock, flags); | |
7589670f SN |
176 | return err; |
177 | } | |
178 | ||
179 | return 0; | |
180 | } | |
181 | EXPORT_SYMBOL_GPL(dca_add_requester); | |
182 | ||
183 | /** | |
184 | * dca_remove_requester - remove a dca client from the list | |
185 | * @dev - the device that wants dca service | |
186 | */ | |
187 | int dca_remove_requester(struct device *dev) | |
188 | { | |
7f1b358a | 189 | struct dca_provider *dca; |
7589670f | 190 | int slot; |
eb4400e3 | 191 | unsigned long flags; |
7f1b358a MS |
192 | |
193 | if (!dev) | |
194 | return -EFAULT; | |
7589670f | 195 | |
eb4400e3 | 196 | spin_lock_irqsave(&dca_lock, flags); |
7f1b358a MS |
197 | dca = dca_find_provider_by_dev(dev); |
198 | if (!dca) { | |
eb4400e3 | 199 | spin_unlock_irqrestore(&dca_lock, flags); |
7f1b358a MS |
200 | return -ENODEV; |
201 | } | |
202 | slot = dca->ops->remove_requester(dca, dev); | |
eb4400e3 MS |
203 | spin_unlock_irqrestore(&dca_lock, flags); |
204 | ||
205 | if (slot < 0) | |
7589670f SN |
206 | return slot; |
207 | ||
7f1b358a MS |
208 | dca_sysfs_remove_req(dca, slot); |
209 | ||
7589670f SN |
210 | return 0; |
211 | } | |
212 | EXPORT_SYMBOL_GPL(dca_remove_requester); | |
213 | ||
214 | /** | |
7f1b358a MS |
215 | * dca_common_get_tag - return the dca tag (serves both new and old api) |
216 | * @dev - the device that wants dca service | |
7589670f SN |
217 | * @cpu - the cpuid as returned by get_cpu() |
218 | */ | |
7f1b358a | 219 | u8 dca_common_get_tag(struct device *dev, int cpu) |
7589670f | 220 | { |
7f1b358a MS |
221 | struct dca_provider *dca; |
222 | u8 tag; | |
eb4400e3 | 223 | unsigned long flags; |
7f1b358a | 224 | |
eb4400e3 | 225 | spin_lock_irqsave(&dca_lock, flags); |
7f1b358a MS |
226 | |
227 | dca = dca_find_provider_by_dev(dev); | |
228 | if (!dca) { | |
eb4400e3 | 229 | spin_unlock_irqrestore(&dca_lock, flags); |
7589670f | 230 | return -ENODEV; |
7f1b358a MS |
231 | } |
232 | tag = dca->ops->get_tag(dca, dev, cpu); | |
233 | ||
eb4400e3 | 234 | spin_unlock_irqrestore(&dca_lock, flags); |
7f1b358a MS |
235 | return tag; |
236 | } | |
237 | ||
238 | /** | |
239 | * dca3_get_tag - return the dca tag to the requester device | |
240 | * for the given cpu (new api) | |
241 | * @dev - the device that wants dca service | |
242 | * @cpu - the cpuid as returned by get_cpu() | |
243 | */ | |
244 | u8 dca3_get_tag(struct device *dev, int cpu) | |
245 | { | |
246 | if (!dev) | |
247 | return -EFAULT; | |
248 | ||
249 | return dca_common_get_tag(dev, cpu); | |
250 | } | |
251 | EXPORT_SYMBOL_GPL(dca3_get_tag); | |
252 | ||
253 | /** | |
254 | * dca_get_tag - return the dca tag for the given cpu (old api) | |
255 | * @cpu - the cpuid as returned by get_cpu() | |
256 | */ | |
257 | u8 dca_get_tag(int cpu) | |
258 | { | |
259 | struct device *dev = NULL; | |
260 | ||
261 | return dca_common_get_tag(dev, cpu); | |
7589670f SN |
262 | } |
263 | EXPORT_SYMBOL_GPL(dca_get_tag); | |
264 | ||
265 | /** | |
266 | * alloc_dca_provider - get data struct for describing a dca provider | |
267 | * @ops - pointer to struct of dca operation function pointers | |
268 | * @priv_size - size of extra mem to be added for provider's needs | |
269 | */ | |
270 | struct dca_provider *alloc_dca_provider(struct dca_ops *ops, int priv_size) | |
271 | { | |
272 | struct dca_provider *dca; | |
273 | int alloc_size; | |
274 | ||
275 | alloc_size = (sizeof(*dca) + priv_size); | |
276 | dca = kzalloc(alloc_size, GFP_KERNEL); | |
277 | if (!dca) | |
278 | return NULL; | |
279 | dca->ops = ops; | |
280 | ||
281 | return dca; | |
282 | } | |
283 | EXPORT_SYMBOL_GPL(alloc_dca_provider); | |
284 | ||
285 | /** | |
286 | * free_dca_provider - release the dca provider data struct | |
287 | * @ops - pointer to struct of dca operation function pointers | |
288 | * @priv_size - size of extra mem to be added for provider's needs | |
289 | */ | |
290 | void free_dca_provider(struct dca_provider *dca) | |
291 | { | |
292 | kfree(dca); | |
293 | } | |
294 | EXPORT_SYMBOL_GPL(free_dca_provider); | |
295 | ||
296 | static BLOCKING_NOTIFIER_HEAD(dca_provider_chain); | |
297 | ||
298 | /** | |
299 | * register_dca_provider - register a dca provider | |
300 | * @dca - struct created by alloc_dca_provider() | |
301 | * @dev - device providing dca services | |
302 | */ | |
303 | int register_dca_provider(struct dca_provider *dca, struct device *dev) | |
304 | { | |
305 | int err; | |
eb4400e3 | 306 | unsigned long flags; |
1a5aeeec | 307 | struct dca_domain *domain; |
7589670f | 308 | |
7589670f SN |
309 | err = dca_sysfs_add_provider(dca, dev); |
310 | if (err) | |
311 | return err; | |
eb4400e3 MS |
312 | |
313 | spin_lock_irqsave(&dca_lock, flags); | |
1a5aeeec MS |
314 | domain = dca_get_domain(dev); |
315 | if (!domain) { | |
316 | spin_unlock_irqrestore(&dca_lock, flags); | |
317 | return -ENODEV; | |
318 | } | |
319 | list_add(&dca->node, &domain->dca_providers); | |
eb4400e3 MS |
320 | spin_unlock_irqrestore(&dca_lock, flags); |
321 | ||
7589670f SN |
322 | blocking_notifier_call_chain(&dca_provider_chain, |
323 | DCA_PROVIDER_ADD, NULL); | |
324 | return 0; | |
325 | } | |
326 | EXPORT_SYMBOL_GPL(register_dca_provider); | |
327 | ||
328 | /** | |
329 | * unregister_dca_provider - remove a dca provider | |
330 | * @dca - struct created by alloc_dca_provider() | |
331 | */ | |
1a5aeeec | 332 | void unregister_dca_provider(struct dca_provider *dca, struct device *dev) |
7589670f | 333 | { |
eb4400e3 | 334 | unsigned long flags; |
1a5aeeec MS |
335 | struct pci_bus *pci_rc; |
336 | struct dca_domain *domain; | |
eb4400e3 | 337 | |
7589670f SN |
338 | blocking_notifier_call_chain(&dca_provider_chain, |
339 | DCA_PROVIDER_REMOVE, NULL); | |
eb4400e3 MS |
340 | |
341 | spin_lock_irqsave(&dca_lock, flags); | |
1a5aeeec | 342 | |
7f1b358a | 343 | list_del(&dca->node); |
1a5aeeec MS |
344 | |
345 | pci_rc = dca_pci_rc_from_dev(dev); | |
346 | domain = dca_find_domain(pci_rc); | |
347 | if (list_empty(&domain->dca_providers)) | |
348 | dca_free_domain(domain); | |
349 | ||
eb4400e3 MS |
350 | spin_unlock_irqrestore(&dca_lock, flags); |
351 | ||
7589670f SN |
352 | dca_sysfs_remove_provider(dca); |
353 | } | |
354 | EXPORT_SYMBOL_GPL(unregister_dca_provider); | |
355 | ||
356 | /** | |
357 | * dca_register_notify - register a client's notifier callback | |
358 | */ | |
359 | void dca_register_notify(struct notifier_block *nb) | |
360 | { | |
361 | blocking_notifier_chain_register(&dca_provider_chain, nb); | |
362 | } | |
363 | EXPORT_SYMBOL_GPL(dca_register_notify); | |
364 | ||
365 | /** | |
366 | * dca_unregister_notify - remove a client's notifier callback | |
367 | */ | |
368 | void dca_unregister_notify(struct notifier_block *nb) | |
369 | { | |
370 | blocking_notifier_chain_unregister(&dca_provider_chain, nb); | |
371 | } | |
372 | EXPORT_SYMBOL_GPL(dca_unregister_notify); | |
373 | ||
374 | static int __init dca_init(void) | |
375 | { | |
084dac53 | 376 | pr_info("dca service started, version %s\n", DCA_VERSION); |
7589670f SN |
377 | return dca_sysfs_init(); |
378 | } | |
379 | ||
380 | static void __exit dca_exit(void) | |
381 | { | |
382 | dca_sysfs_exit(); | |
383 | } | |
384 | ||
652afc27 | 385 | arch_initcall(dca_init); |
7589670f SN |
386 | module_exit(dca_exit); |
387 |