]>
Commit | Line | Data |
---|---|---|
1 | // SPDX-License-Identifier: GPL-2.0-or-later | |
2 | /* | |
3 | * Routines for driver control interface | |
4 | * Copyright (c) by Jaroslav Kysela <perex@perex.cz> | |
5 | */ | |
6 | ||
7 | #include <linux/threads.h> | |
8 | #include <linux/interrupt.h> | |
9 | #include <linux/module.h> | |
10 | #include <linux/moduleparam.h> | |
11 | #include <linux/slab.h> | |
12 | #include <linux/vmalloc.h> | |
13 | #include <linux/time.h> | |
14 | #include <linux/mm.h> | |
15 | #include <linux/math64.h> | |
16 | #include <linux/sched/signal.h> | |
17 | #include <sound/core.h> | |
18 | #include <sound/minors.h> | |
19 | #include <sound/info.h> | |
20 | #include <sound/control.h> | |
21 | ||
22 | // Max allocation size for user controls. | |
23 | static int max_user_ctl_alloc_size = 8 * 1024 * 1024; | |
24 | module_param_named(max_user_ctl_alloc_size, max_user_ctl_alloc_size, int, 0444); | |
25 | MODULE_PARM_DESC(max_user_ctl_alloc_size, "Max allocation size for user controls"); | |
26 | ||
27 | #define MAX_CONTROL_COUNT 1028 | |
28 | ||
29 | struct snd_kctl_ioctl { | |
30 | struct list_head list; /* list of all ioctls */ | |
31 | snd_kctl_ioctl_func_t fioctl; | |
32 | }; | |
33 | ||
34 | static DECLARE_RWSEM(snd_ioctl_rwsem); | |
35 | static DECLARE_RWSEM(snd_ctl_layer_rwsem); | |
36 | static LIST_HEAD(snd_control_ioctls); | |
37 | #ifdef CONFIG_COMPAT | |
38 | static LIST_HEAD(snd_control_compat_ioctls); | |
39 | #endif | |
40 | static struct snd_ctl_layer_ops *snd_ctl_layer; | |
41 | ||
42 | static int snd_ctl_remove_locked(struct snd_card *card, | |
43 | struct snd_kcontrol *kcontrol); | |
44 | ||
45 | static int snd_ctl_open(struct inode *inode, struct file *file) | |
46 | { | |
47 | struct snd_card *card; | |
48 | struct snd_ctl_file *ctl; | |
49 | int i, err; | |
50 | ||
51 | err = stream_open(inode, file); | |
52 | if (err < 0) | |
53 | return err; | |
54 | ||
55 | card = snd_lookup_minor_data(iminor(inode), SNDRV_DEVICE_TYPE_CONTROL); | |
56 | if (!card) { | |
57 | err = -ENODEV; | |
58 | goto __error1; | |
59 | } | |
60 | err = snd_card_file_add(card, file); | |
61 | if (err < 0) { | |
62 | err = -ENODEV; | |
63 | goto __error1; | |
64 | } | |
65 | if (!try_module_get(card->module)) { | |
66 | err = -EFAULT; | |
67 | goto __error2; | |
68 | } | |
69 | ctl = kzalloc(sizeof(*ctl), GFP_KERNEL); | |
70 | if (ctl == NULL) { | |
71 | err = -ENOMEM; | |
72 | goto __error; | |
73 | } | |
74 | INIT_LIST_HEAD(&ctl->events); | |
75 | init_waitqueue_head(&ctl->change_sleep); | |
76 | spin_lock_init(&ctl->read_lock); | |
77 | ctl->card = card; | |
78 | for (i = 0; i < SND_CTL_SUBDEV_ITEMS; i++) | |
79 | ctl->preferred_subdevice[i] = -1; | |
80 | ctl->pid = get_pid(task_pid(current)); | |
81 | file->private_data = ctl; | |
82 | scoped_guard(write_lock_irqsave, &card->ctl_files_rwlock) | |
83 | list_add_tail(&ctl->list, &card->ctl_files); | |
84 | snd_card_unref(card); | |
85 | return 0; | |
86 | ||
87 | __error: | |
88 | module_put(card->module); | |
89 | __error2: | |
90 | snd_card_file_remove(card, file); | |
91 | __error1: | |
92 | if (card) | |
93 | snd_card_unref(card); | |
94 | return err; | |
95 | } | |
96 | ||
97 | static void snd_ctl_empty_read_queue(struct snd_ctl_file * ctl) | |
98 | { | |
99 | struct snd_kctl_event *cread; | |
100 | ||
101 | guard(spinlock_irqsave)(&ctl->read_lock); | |
102 | while (!list_empty(&ctl->events)) { | |
103 | cread = snd_kctl_event(ctl->events.next); | |
104 | list_del(&cread->list); | |
105 | kfree(cread); | |
106 | } | |
107 | } | |
108 | ||
109 | static int snd_ctl_release(struct inode *inode, struct file *file) | |
110 | { | |
111 | struct snd_card *card; | |
112 | struct snd_ctl_file *ctl; | |
113 | struct snd_kcontrol *control; | |
114 | unsigned int idx; | |
115 | ||
116 | ctl = file->private_data; | |
117 | file->private_data = NULL; | |
118 | card = ctl->card; | |
119 | ||
120 | scoped_guard(write_lock_irqsave, &card->ctl_files_rwlock) | |
121 | list_del(&ctl->list); | |
122 | ||
123 | scoped_guard(rwsem_write, &card->controls_rwsem) { | |
124 | list_for_each_entry(control, &card->controls, list) | |
125 | for (idx = 0; idx < control->count; idx++) | |
126 | if (control->vd[idx].owner == ctl) | |
127 | control->vd[idx].owner = NULL; | |
128 | } | |
129 | ||
130 | snd_fasync_free(ctl->fasync); | |
131 | snd_ctl_empty_read_queue(ctl); | |
132 | put_pid(ctl->pid); | |
133 | kfree(ctl); | |
134 | module_put(card->module); | |
135 | snd_card_file_remove(card, file); | |
136 | return 0; | |
137 | } | |
138 | ||
139 | /** | |
140 | * snd_ctl_notify - Send notification to user-space for a control change | |
141 | * @card: the card to send notification | |
142 | * @mask: the event mask, SNDRV_CTL_EVENT_* | |
143 | * @id: the ctl element id to send notification | |
144 | * | |
145 | * This function adds an event record with the given id and mask, appends | |
146 | * to the list and wakes up the user-space for notification. This can be | |
147 | * called in the atomic context. | |
148 | */ | |
149 | void snd_ctl_notify(struct snd_card *card, unsigned int mask, | |
150 | struct snd_ctl_elem_id *id) | |
151 | { | |
152 | struct snd_ctl_file *ctl; | |
153 | struct snd_kctl_event *ev; | |
154 | ||
155 | if (snd_BUG_ON(!card || !id)) | |
156 | return; | |
157 | if (card->shutdown) | |
158 | return; | |
159 | ||
160 | guard(read_lock_irqsave)(&card->ctl_files_rwlock); | |
161 | #if IS_ENABLED(CONFIG_SND_MIXER_OSS) | |
162 | card->mixer_oss_change_count++; | |
163 | #endif | |
164 | list_for_each_entry(ctl, &card->ctl_files, list) { | |
165 | if (!ctl->subscribed) | |
166 | continue; | |
167 | scoped_guard(spinlock, &ctl->read_lock) { | |
168 | list_for_each_entry(ev, &ctl->events, list) { | |
169 | if (ev->id.numid == id->numid) { | |
170 | ev->mask |= mask; | |
171 | goto _found; | |
172 | } | |
173 | } | |
174 | ev = kzalloc(sizeof(*ev), GFP_ATOMIC); | |
175 | if (ev) { | |
176 | ev->id = *id; | |
177 | ev->mask = mask; | |
178 | list_add_tail(&ev->list, &ctl->events); | |
179 | } else { | |
180 | dev_err(card->dev, "No memory available to allocate event\n"); | |
181 | } | |
182 | _found: | |
183 | wake_up(&ctl->change_sleep); | |
184 | } | |
185 | snd_kill_fasync(ctl->fasync, SIGIO, POLL_IN); | |
186 | } | |
187 | } | |
188 | EXPORT_SYMBOL(snd_ctl_notify); | |
189 | ||
190 | /** | |
191 | * snd_ctl_notify_one - Send notification to user-space for a control change | |
192 | * @card: the card to send notification | |
193 | * @mask: the event mask, SNDRV_CTL_EVENT_* | |
194 | * @kctl: the pointer with the control instance | |
195 | * @ioff: the additional offset to the control index | |
196 | * | |
197 | * This function calls snd_ctl_notify() and does additional jobs | |
198 | * like LED state changes. | |
199 | */ | |
200 | void snd_ctl_notify_one(struct snd_card *card, unsigned int mask, | |
201 | struct snd_kcontrol *kctl, unsigned int ioff) | |
202 | { | |
203 | struct snd_ctl_elem_id id = kctl->id; | |
204 | struct snd_ctl_layer_ops *lops; | |
205 | ||
206 | id.index += ioff; | |
207 | id.numid += ioff; | |
208 | snd_ctl_notify(card, mask, &id); | |
209 | guard(rwsem_read)(&snd_ctl_layer_rwsem); | |
210 | for (lops = snd_ctl_layer; lops; lops = lops->next) | |
211 | lops->lnotify(card, mask, kctl, ioff); | |
212 | } | |
213 | EXPORT_SYMBOL(snd_ctl_notify_one); | |
214 | ||
215 | /** | |
216 | * snd_ctl_new - create a new control instance with some elements | |
217 | * @kctl: the pointer to store new control instance | |
218 | * @count: the number of elements in this control | |
219 | * @access: the default access flags for elements in this control | |
220 | * @file: given when locking these elements | |
221 | * | |
222 | * Allocates a memory object for a new control instance. The instance has | |
223 | * elements as many as the given number (@count). Each element has given | |
224 | * access permissions (@access). Each element is locked when @file is given. | |
225 | * | |
226 | * Return: 0 on success, error code on failure | |
227 | */ | |
228 | static int snd_ctl_new(struct snd_kcontrol **kctl, unsigned int count, | |
229 | unsigned int access, struct snd_ctl_file *file) | |
230 | { | |
231 | unsigned int idx; | |
232 | ||
233 | if (count == 0 || count > MAX_CONTROL_COUNT) | |
234 | return -EINVAL; | |
235 | ||
236 | *kctl = kzalloc(struct_size(*kctl, vd, count), GFP_KERNEL); | |
237 | if (!*kctl) | |
238 | return -ENOMEM; | |
239 | ||
240 | for (idx = 0; idx < count; idx++) { | |
241 | (*kctl)->vd[idx].access = access; | |
242 | (*kctl)->vd[idx].owner = file; | |
243 | } | |
244 | (*kctl)->count = count; | |
245 | ||
246 | return 0; | |
247 | } | |
248 | ||
249 | /** | |
250 | * snd_ctl_new1 - create a control instance from the template | |
251 | * @ncontrol: the initialization record | |
252 | * @private_data: the private data to set | |
253 | * | |
254 | * Allocates a new struct snd_kcontrol instance and initialize from the given | |
255 | * template. When the access field of ncontrol is 0, it's assumed as | |
256 | * READWRITE access. When the count field is 0, it's assumes as one. | |
257 | * | |
258 | * Return: The pointer of the newly generated instance, or %NULL on failure. | |
259 | */ | |
260 | struct snd_kcontrol *snd_ctl_new1(const struct snd_kcontrol_new *ncontrol, | |
261 | void *private_data) | |
262 | { | |
263 | struct snd_kcontrol *kctl; | |
264 | unsigned int count; | |
265 | unsigned int access; | |
266 | int err; | |
267 | ||
268 | if (snd_BUG_ON(!ncontrol || !ncontrol->info)) | |
269 | return NULL; | |
270 | ||
271 | count = ncontrol->count; | |
272 | if (count == 0) | |
273 | count = 1; | |
274 | ||
275 | access = ncontrol->access; | |
276 | if (access == 0) | |
277 | access = SNDRV_CTL_ELEM_ACCESS_READWRITE; | |
278 | access &= (SNDRV_CTL_ELEM_ACCESS_READWRITE | | |
279 | SNDRV_CTL_ELEM_ACCESS_VOLATILE | | |
280 | SNDRV_CTL_ELEM_ACCESS_INACTIVE | | |
281 | SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE | | |
282 | SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND | | |
283 | SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK | | |
284 | SNDRV_CTL_ELEM_ACCESS_LED_MASK | | |
285 | SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK); | |
286 | ||
287 | err = snd_ctl_new(&kctl, count, access, NULL); | |
288 | if (err < 0) | |
289 | return NULL; | |
290 | ||
291 | /* The 'numid' member is decided when calling snd_ctl_add(). */ | |
292 | kctl->id.iface = ncontrol->iface; | |
293 | kctl->id.device = ncontrol->device; | |
294 | kctl->id.subdevice = ncontrol->subdevice; | |
295 | if (ncontrol->name) { | |
296 | strscpy(kctl->id.name, ncontrol->name, sizeof(kctl->id.name)); | |
297 | if (strcmp(ncontrol->name, kctl->id.name) != 0) | |
298 | pr_warn("ALSA: Control name '%s' truncated to '%s'\n", | |
299 | ncontrol->name, kctl->id.name); | |
300 | } | |
301 | kctl->id.index = ncontrol->index; | |
302 | ||
303 | kctl->info = ncontrol->info; | |
304 | kctl->get = ncontrol->get; | |
305 | kctl->put = ncontrol->put; | |
306 | kctl->tlv.p = ncontrol->tlv.p; | |
307 | ||
308 | kctl->private_value = ncontrol->private_value; | |
309 | kctl->private_data = private_data; | |
310 | ||
311 | return kctl; | |
312 | } | |
313 | EXPORT_SYMBOL(snd_ctl_new1); | |
314 | ||
315 | /** | |
316 | * snd_ctl_free_one - release the control instance | |
317 | * @kcontrol: the control instance | |
318 | * | |
319 | * Releases the control instance created via snd_ctl_new() | |
320 | * or snd_ctl_new1(). | |
321 | * Don't call this after the control was added to the card. | |
322 | */ | |
323 | void snd_ctl_free_one(struct snd_kcontrol *kcontrol) | |
324 | { | |
325 | if (kcontrol) { | |
326 | if (kcontrol->private_free) | |
327 | kcontrol->private_free(kcontrol); | |
328 | kfree(kcontrol); | |
329 | } | |
330 | } | |
331 | EXPORT_SYMBOL(snd_ctl_free_one); | |
332 | ||
333 | static bool snd_ctl_remove_numid_conflict(struct snd_card *card, | |
334 | unsigned int count) | |
335 | { | |
336 | struct snd_kcontrol *kctl; | |
337 | ||
338 | /* Make sure that the ids assigned to the control do not wrap around */ | |
339 | if (card->last_numid >= UINT_MAX - count) | |
340 | card->last_numid = 0; | |
341 | ||
342 | list_for_each_entry(kctl, &card->controls, list) { | |
343 | if (kctl->id.numid < card->last_numid + 1 + count && | |
344 | kctl->id.numid + kctl->count > card->last_numid + 1) { | |
345 | card->last_numid = kctl->id.numid + kctl->count - 1; | |
346 | return true; | |
347 | } | |
348 | } | |
349 | return false; | |
350 | } | |
351 | ||
352 | static int snd_ctl_find_hole(struct snd_card *card, unsigned int count) | |
353 | { | |
354 | unsigned int iter = 100000; | |
355 | ||
356 | while (snd_ctl_remove_numid_conflict(card, count)) { | |
357 | if (--iter == 0) { | |
358 | /* this situation is very unlikely */ | |
359 | dev_err(card->dev, "unable to allocate new control numid\n"); | |
360 | return -ENOMEM; | |
361 | } | |
362 | } | |
363 | return 0; | |
364 | } | |
365 | ||
366 | /* check whether the given id is contained in the given kctl */ | |
367 | static bool elem_id_matches(const struct snd_kcontrol *kctl, | |
368 | const struct snd_ctl_elem_id *id) | |
369 | { | |
370 | return kctl->id.iface == id->iface && | |
371 | kctl->id.device == id->device && | |
372 | kctl->id.subdevice == id->subdevice && | |
373 | !strncmp(kctl->id.name, id->name, sizeof(kctl->id.name)) && | |
374 | kctl->id.index <= id->index && | |
375 | kctl->id.index + kctl->count > id->index; | |
376 | } | |
377 | ||
378 | #ifdef CONFIG_SND_CTL_FAST_LOOKUP | |
379 | /* Compute a hash key for the corresponding ctl id | |
380 | * It's for the name lookup, hence the numid is excluded. | |
381 | * The hash key is bound in LONG_MAX to be used for Xarray key. | |
382 | */ | |
383 | #define MULTIPLIER 37 | |
384 | static unsigned long get_ctl_id_hash(const struct snd_ctl_elem_id *id) | |
385 | { | |
386 | int i; | |
387 | unsigned long h; | |
388 | ||
389 | h = id->iface; | |
390 | h = MULTIPLIER * h + id->device; | |
391 | h = MULTIPLIER * h + id->subdevice; | |
392 | for (i = 0; i < SNDRV_CTL_ELEM_ID_NAME_MAXLEN && id->name[i]; i++) | |
393 | h = MULTIPLIER * h + id->name[i]; | |
394 | h = MULTIPLIER * h + id->index; | |
395 | h &= LONG_MAX; | |
396 | return h; | |
397 | } | |
398 | ||
399 | /* add hash entries to numid and ctl xarray tables */ | |
400 | static void add_hash_entries(struct snd_card *card, | |
401 | struct snd_kcontrol *kcontrol) | |
402 | { | |
403 | struct snd_ctl_elem_id id = kcontrol->id; | |
404 | int i; | |
405 | ||
406 | xa_store_range(&card->ctl_numids, kcontrol->id.numid, | |
407 | kcontrol->id.numid + kcontrol->count - 1, | |
408 | kcontrol, GFP_KERNEL); | |
409 | ||
410 | for (i = 0; i < kcontrol->count; i++) { | |
411 | id.index = kcontrol->id.index + i; | |
412 | if (xa_insert(&card->ctl_hash, get_ctl_id_hash(&id), | |
413 | kcontrol, GFP_KERNEL)) { | |
414 | /* skip hash for this entry, noting we had collision */ | |
415 | card->ctl_hash_collision = true; | |
416 | dev_dbg(card->dev, "ctl_hash collision %d:%s:%d\n", | |
417 | id.iface, id.name, id.index); | |
418 | } | |
419 | } | |
420 | } | |
421 | ||
422 | /* remove hash entries that have been added */ | |
423 | static void remove_hash_entries(struct snd_card *card, | |
424 | struct snd_kcontrol *kcontrol) | |
425 | { | |
426 | struct snd_ctl_elem_id id = kcontrol->id; | |
427 | struct snd_kcontrol *matched; | |
428 | unsigned long h; | |
429 | int i; | |
430 | ||
431 | for (i = 0; i < kcontrol->count; i++) { | |
432 | xa_erase(&card->ctl_numids, id.numid); | |
433 | h = get_ctl_id_hash(&id); | |
434 | matched = xa_load(&card->ctl_hash, h); | |
435 | if (matched && (matched == kcontrol || | |
436 | elem_id_matches(matched, &id))) | |
437 | xa_erase(&card->ctl_hash, h); | |
438 | id.index++; | |
439 | id.numid++; | |
440 | } | |
441 | } | |
442 | #else /* CONFIG_SND_CTL_FAST_LOOKUP */ | |
443 | static inline void add_hash_entries(struct snd_card *card, | |
444 | struct snd_kcontrol *kcontrol) | |
445 | { | |
446 | } | |
447 | static inline void remove_hash_entries(struct snd_card *card, | |
448 | struct snd_kcontrol *kcontrol) | |
449 | { | |
450 | } | |
451 | #endif /* CONFIG_SND_CTL_FAST_LOOKUP */ | |
452 | ||
453 | enum snd_ctl_add_mode { | |
454 | CTL_ADD_EXCLUSIVE, CTL_REPLACE, CTL_ADD_ON_REPLACE, | |
455 | }; | |
456 | ||
457 | /* add/replace a new kcontrol object; call with card->controls_rwsem locked */ | |
458 | static int __snd_ctl_add_replace(struct snd_card *card, | |
459 | struct snd_kcontrol *kcontrol, | |
460 | enum snd_ctl_add_mode mode) | |
461 | { | |
462 | struct snd_ctl_elem_id id; | |
463 | unsigned int idx; | |
464 | struct snd_kcontrol *old; | |
465 | int err; | |
466 | ||
467 | lockdep_assert_held_write(&card->controls_rwsem); | |
468 | ||
469 | id = kcontrol->id; | |
470 | if (id.index > UINT_MAX - kcontrol->count) | |
471 | return -EINVAL; | |
472 | ||
473 | old = snd_ctl_find_id_locked(card, &id); | |
474 | if (!old) { | |
475 | if (mode == CTL_REPLACE) | |
476 | return -EINVAL; | |
477 | } else { | |
478 | if (mode == CTL_ADD_EXCLUSIVE) { | |
479 | dev_err(card->dev, | |
480 | "control %i:%i:%i:%s:%i is already present\n", | |
481 | id.iface, id.device, id.subdevice, id.name, | |
482 | id.index); | |
483 | return -EBUSY; | |
484 | } | |
485 | ||
486 | err = snd_ctl_remove_locked(card, old); | |
487 | if (err < 0) | |
488 | return err; | |
489 | } | |
490 | ||
491 | if (snd_ctl_find_hole(card, kcontrol->count) < 0) | |
492 | return -ENOMEM; | |
493 | ||
494 | list_add_tail(&kcontrol->list, &card->controls); | |
495 | card->controls_count += kcontrol->count; | |
496 | kcontrol->id.numid = card->last_numid + 1; | |
497 | card->last_numid += kcontrol->count; | |
498 | ||
499 | add_hash_entries(card, kcontrol); | |
500 | ||
501 | for (idx = 0; idx < kcontrol->count; idx++) | |
502 | snd_ctl_notify_one(card, SNDRV_CTL_EVENT_MASK_ADD, kcontrol, idx); | |
503 | ||
504 | return 0; | |
505 | } | |
506 | ||
507 | static int snd_ctl_add_replace(struct snd_card *card, | |
508 | struct snd_kcontrol *kcontrol, | |
509 | enum snd_ctl_add_mode mode) | |
510 | { | |
511 | int err = -EINVAL; | |
512 | ||
513 | if (! kcontrol) | |
514 | return err; | |
515 | if (snd_BUG_ON(!card || !kcontrol->info)) | |
516 | goto error; | |
517 | ||
518 | scoped_guard(rwsem_write, &card->controls_rwsem) | |
519 | err = __snd_ctl_add_replace(card, kcontrol, mode); | |
520 | ||
521 | if (err < 0) | |
522 | goto error; | |
523 | return 0; | |
524 | ||
525 | error: | |
526 | snd_ctl_free_one(kcontrol); | |
527 | return err; | |
528 | } | |
529 | ||
530 | /** | |
531 | * snd_ctl_add - add the control instance to the card | |
532 | * @card: the card instance | |
533 | * @kcontrol: the control instance to add | |
534 | * | |
535 | * Adds the control instance created via snd_ctl_new() or | |
536 | * snd_ctl_new1() to the given card. Assigns also an unique | |
537 | * numid used for fast search. | |
538 | * | |
539 | * It frees automatically the control which cannot be added. | |
540 | * | |
541 | * Return: Zero if successful, or a negative error code on failure. | |
542 | * | |
543 | */ | |
544 | int snd_ctl_add(struct snd_card *card, struct snd_kcontrol *kcontrol) | |
545 | { | |
546 | return snd_ctl_add_replace(card, kcontrol, CTL_ADD_EXCLUSIVE); | |
547 | } | |
548 | EXPORT_SYMBOL(snd_ctl_add); | |
549 | ||
550 | /** | |
551 | * snd_ctl_replace - replace the control instance of the card | |
552 | * @card: the card instance | |
553 | * @kcontrol: the control instance to replace | |
554 | * @add_on_replace: add the control if not already added | |
555 | * | |
556 | * Replaces the given control. If the given control does not exist | |
557 | * and the add_on_replace flag is set, the control is added. If the | |
558 | * control exists, it is destroyed first. | |
559 | * | |
560 | * It frees automatically the control which cannot be added or replaced. | |
561 | * | |
562 | * Return: Zero if successful, or a negative error code on failure. | |
563 | */ | |
564 | int snd_ctl_replace(struct snd_card *card, struct snd_kcontrol *kcontrol, | |
565 | bool add_on_replace) | |
566 | { | |
567 | return snd_ctl_add_replace(card, kcontrol, | |
568 | add_on_replace ? CTL_ADD_ON_REPLACE : CTL_REPLACE); | |
569 | } | |
570 | EXPORT_SYMBOL(snd_ctl_replace); | |
571 | ||
572 | static int __snd_ctl_remove(struct snd_card *card, | |
573 | struct snd_kcontrol *kcontrol, | |
574 | bool remove_hash) | |
575 | { | |
576 | unsigned int idx; | |
577 | ||
578 | lockdep_assert_held_write(&card->controls_rwsem); | |
579 | ||
580 | if (snd_BUG_ON(!card || !kcontrol)) | |
581 | return -EINVAL; | |
582 | list_del(&kcontrol->list); | |
583 | ||
584 | if (remove_hash) | |
585 | remove_hash_entries(card, kcontrol); | |
586 | ||
587 | card->controls_count -= kcontrol->count; | |
588 | for (idx = 0; idx < kcontrol->count; idx++) | |
589 | snd_ctl_notify_one(card, SNDRV_CTL_EVENT_MASK_REMOVE, kcontrol, idx); | |
590 | snd_ctl_free_one(kcontrol); | |
591 | return 0; | |
592 | } | |
593 | ||
594 | static inline int snd_ctl_remove_locked(struct snd_card *card, | |
595 | struct snd_kcontrol *kcontrol) | |
596 | { | |
597 | return __snd_ctl_remove(card, kcontrol, true); | |
598 | } | |
599 | ||
600 | /** | |
601 | * snd_ctl_remove - remove the control from the card and release it | |
602 | * @card: the card instance | |
603 | * @kcontrol: the control instance to remove | |
604 | * | |
605 | * Removes the control from the card and then releases the instance. | |
606 | * You don't need to call snd_ctl_free_one(). | |
607 | * | |
608 | * Return: 0 if successful, or a negative error code on failure. | |
609 | * | |
610 | * Note that this function takes card->controls_rwsem lock internally. | |
611 | */ | |
612 | int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol) | |
613 | { | |
614 | guard(rwsem_write)(&card->controls_rwsem); | |
615 | return snd_ctl_remove_locked(card, kcontrol); | |
616 | } | |
617 | EXPORT_SYMBOL(snd_ctl_remove); | |
618 | ||
619 | /** | |
620 | * snd_ctl_remove_id - remove the control of the given id and release it | |
621 | * @card: the card instance | |
622 | * @id: the control id to remove | |
623 | * | |
624 | * Finds the control instance with the given id, removes it from the | |
625 | * card list and releases it. | |
626 | * | |
627 | * Return: 0 if successful, or a negative error code on failure. | |
628 | */ | |
629 | int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id) | |
630 | { | |
631 | struct snd_kcontrol *kctl; | |
632 | ||
633 | guard(rwsem_write)(&card->controls_rwsem); | |
634 | kctl = snd_ctl_find_id_locked(card, id); | |
635 | if (kctl == NULL) | |
636 | return -ENOENT; | |
637 | return snd_ctl_remove_locked(card, kctl); | |
638 | } | |
639 | EXPORT_SYMBOL(snd_ctl_remove_id); | |
640 | ||
641 | /** | |
642 | * snd_ctl_remove_user_ctl - remove and release the unlocked user control | |
643 | * @file: active control handle | |
644 | * @id: the control id to remove | |
645 | * | |
646 | * Finds the control instance with the given id, removes it from the | |
647 | * card list and releases it. | |
648 | * | |
649 | * Return: 0 if successful, or a negative error code on failure. | |
650 | */ | |
651 | static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file, | |
652 | struct snd_ctl_elem_id *id) | |
653 | { | |
654 | struct snd_card *card = file->card; | |
655 | struct snd_kcontrol *kctl; | |
656 | int idx; | |
657 | ||
658 | guard(rwsem_write)(&card->controls_rwsem); | |
659 | kctl = snd_ctl_find_id_locked(card, id); | |
660 | if (kctl == NULL) | |
661 | return -ENOENT; | |
662 | if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) | |
663 | return -EINVAL; | |
664 | for (idx = 0; idx < kctl->count; idx++) | |
665 | if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) | |
666 | return -EBUSY; | |
667 | return snd_ctl_remove_locked(card, kctl); | |
668 | } | |
669 | ||
670 | /** | |
671 | * snd_ctl_activate_id - activate/inactivate the control of the given id | |
672 | * @card: the card instance | |
673 | * @id: the control id to activate/inactivate | |
674 | * @active: non-zero to activate | |
675 | * | |
676 | * Finds the control instance with the given id, and activate or | |
677 | * inactivate the control together with notification, if changed. | |
678 | * The given ID data is filled with full information. | |
679 | * | |
680 | * Return: 0 if unchanged, 1 if changed, or a negative error code on failure. | |
681 | */ | |
682 | int snd_ctl_activate_id(struct snd_card *card, struct snd_ctl_elem_id *id, | |
683 | int active) | |
684 | { | |
685 | struct snd_kcontrol *kctl; | |
686 | struct snd_kcontrol_volatile *vd; | |
687 | unsigned int index_offset; | |
688 | int ret; | |
689 | ||
690 | down_write(&card->controls_rwsem); | |
691 | kctl = snd_ctl_find_id_locked(card, id); | |
692 | if (kctl == NULL) { | |
693 | ret = -ENOENT; | |
694 | goto unlock; | |
695 | } | |
696 | index_offset = snd_ctl_get_ioff(kctl, id); | |
697 | vd = &kctl->vd[index_offset]; | |
698 | ret = 0; | |
699 | if (active) { | |
700 | if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE)) | |
701 | goto unlock; | |
702 | vd->access &= ~SNDRV_CTL_ELEM_ACCESS_INACTIVE; | |
703 | } else { | |
704 | if (vd->access & SNDRV_CTL_ELEM_ACCESS_INACTIVE) | |
705 | goto unlock; | |
706 | vd->access |= SNDRV_CTL_ELEM_ACCESS_INACTIVE; | |
707 | } | |
708 | snd_ctl_build_ioff(id, kctl, index_offset); | |
709 | downgrade_write(&card->controls_rwsem); | |
710 | snd_ctl_notify_one(card, SNDRV_CTL_EVENT_MASK_INFO, kctl, index_offset); | |
711 | up_read(&card->controls_rwsem); | |
712 | return 1; | |
713 | ||
714 | unlock: | |
715 | up_write(&card->controls_rwsem); | |
716 | return ret; | |
717 | } | |
718 | EXPORT_SYMBOL_GPL(snd_ctl_activate_id); | |
719 | ||
720 | /** | |
721 | * snd_ctl_rename_id - replace the id of a control on the card | |
722 | * @card: the card instance | |
723 | * @src_id: the old id | |
724 | * @dst_id: the new id | |
725 | * | |
726 | * Finds the control with the old id from the card, and replaces the | |
727 | * id with the new one. | |
728 | * | |
729 | * The function tries to keep the already assigned numid while replacing | |
730 | * the rest. | |
731 | * | |
732 | * Note that this function should be used only in the card initialization | |
733 | * phase. Calling after the card instantiation may cause issues with | |
734 | * user-space expecting persistent numids. | |
735 | * | |
736 | * Return: Zero if successful, or a negative error code on failure. | |
737 | */ | |
738 | int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id, | |
739 | struct snd_ctl_elem_id *dst_id) | |
740 | { | |
741 | struct snd_kcontrol *kctl; | |
742 | int saved_numid; | |
743 | ||
744 | guard(rwsem_write)(&card->controls_rwsem); | |
745 | kctl = snd_ctl_find_id_locked(card, src_id); | |
746 | if (kctl == NULL) | |
747 | return -ENOENT; | |
748 | saved_numid = kctl->id.numid; | |
749 | remove_hash_entries(card, kctl); | |
750 | kctl->id = *dst_id; | |
751 | kctl->id.numid = saved_numid; | |
752 | add_hash_entries(card, kctl); | |
753 | return 0; | |
754 | } | |
755 | EXPORT_SYMBOL(snd_ctl_rename_id); | |
756 | ||
757 | /** | |
758 | * snd_ctl_rename - rename the control on the card | |
759 | * @card: the card instance | |
760 | * @kctl: the control to rename | |
761 | * @name: the new name | |
762 | * | |
763 | * Renames the specified control on the card to the new name. | |
764 | * | |
765 | * Note that this function takes card->controls_rwsem lock internally. | |
766 | */ | |
767 | void snd_ctl_rename(struct snd_card *card, struct snd_kcontrol *kctl, | |
768 | const char *name) | |
769 | { | |
770 | guard(rwsem_write)(&card->controls_rwsem); | |
771 | remove_hash_entries(card, kctl); | |
772 | ||
773 | if (strscpy(kctl->id.name, name, sizeof(kctl->id.name)) < 0) | |
774 | pr_warn("ALSA: Renamed control new name '%s' truncated to '%s'\n", | |
775 | name, kctl->id.name); | |
776 | ||
777 | add_hash_entries(card, kctl); | |
778 | } | |
779 | EXPORT_SYMBOL(snd_ctl_rename); | |
780 | ||
781 | #ifndef CONFIG_SND_CTL_FAST_LOOKUP | |
782 | static struct snd_kcontrol * | |
783 | snd_ctl_find_numid_slow(struct snd_card *card, unsigned int numid) | |
784 | { | |
785 | struct snd_kcontrol *kctl; | |
786 | ||
787 | list_for_each_entry(kctl, &card->controls, list) { | |
788 | if (kctl->id.numid <= numid && kctl->id.numid + kctl->count > numid) | |
789 | return kctl; | |
790 | } | |
791 | return NULL; | |
792 | } | |
793 | #endif /* !CONFIG_SND_CTL_FAST_LOOKUP */ | |
794 | ||
795 | /** | |
796 | * snd_ctl_find_numid_locked - find the control instance with the given number-id | |
797 | * @card: the card instance | |
798 | * @numid: the number-id to search | |
799 | * | |
800 | * Finds the control instance with the given number-id from the card. | |
801 | * | |
802 | * The caller must down card->controls_rwsem before calling this function | |
803 | * (if the race condition can happen). | |
804 | * | |
805 | * Return: The pointer of the instance if found, or %NULL if not. | |
806 | */ | |
807 | struct snd_kcontrol * | |
808 | snd_ctl_find_numid_locked(struct snd_card *card, unsigned int numid) | |
809 | { | |
810 | if (snd_BUG_ON(!card || !numid)) | |
811 | return NULL; | |
812 | lockdep_assert_held(&card->controls_rwsem); | |
813 | #ifdef CONFIG_SND_CTL_FAST_LOOKUP | |
814 | return xa_load(&card->ctl_numids, numid); | |
815 | #else | |
816 | return snd_ctl_find_numid_slow(card, numid); | |
817 | #endif | |
818 | } | |
819 | EXPORT_SYMBOL(snd_ctl_find_numid_locked); | |
820 | ||
821 | /** | |
822 | * snd_ctl_find_numid - find the control instance with the given number-id | |
823 | * @card: the card instance | |
824 | * @numid: the number-id to search | |
825 | * | |
826 | * Finds the control instance with the given number-id from the card. | |
827 | * | |
828 | * Return: The pointer of the instance if found, or %NULL if not. | |
829 | * | |
830 | * Note that this function takes card->controls_rwsem lock internally. | |
831 | */ | |
832 | struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, | |
833 | unsigned int numid) | |
834 | { | |
835 | guard(rwsem_read)(&card->controls_rwsem); | |
836 | return snd_ctl_find_numid_locked(card, numid); | |
837 | } | |
838 | EXPORT_SYMBOL(snd_ctl_find_numid); | |
839 | ||
840 | /** | |
841 | * snd_ctl_find_id_locked - find the control instance with the given id | |
842 | * @card: the card instance | |
843 | * @id: the id to search | |
844 | * | |
845 | * Finds the control instance with the given id from the card. | |
846 | * | |
847 | * The caller must down card->controls_rwsem before calling this function | |
848 | * (if the race condition can happen). | |
849 | * | |
850 | * Return: The pointer of the instance if found, or %NULL if not. | |
851 | */ | |
852 | struct snd_kcontrol *snd_ctl_find_id_locked(struct snd_card *card, | |
853 | const struct snd_ctl_elem_id *id) | |
854 | { | |
855 | struct snd_kcontrol *kctl; | |
856 | ||
857 | if (snd_BUG_ON(!card || !id)) | |
858 | return NULL; | |
859 | lockdep_assert_held(&card->controls_rwsem); | |
860 | if (id->numid != 0) | |
861 | return snd_ctl_find_numid_locked(card, id->numid); | |
862 | #ifdef CONFIG_SND_CTL_FAST_LOOKUP | |
863 | kctl = xa_load(&card->ctl_hash, get_ctl_id_hash(id)); | |
864 | if (kctl && elem_id_matches(kctl, id)) | |
865 | return kctl; | |
866 | if (!card->ctl_hash_collision) | |
867 | return NULL; /* we can rely on only hash table */ | |
868 | #endif | |
869 | /* no matching in hash table - try all as the last resort */ | |
870 | list_for_each_entry(kctl, &card->controls, list) | |
871 | if (elem_id_matches(kctl, id)) | |
872 | return kctl; | |
873 | ||
874 | return NULL; | |
875 | } | |
876 | EXPORT_SYMBOL(snd_ctl_find_id_locked); | |
877 | ||
878 | /** | |
879 | * snd_ctl_find_id - find the control instance with the given id | |
880 | * @card: the card instance | |
881 | * @id: the id to search | |
882 | * | |
883 | * Finds the control instance with the given id from the card. | |
884 | * | |
885 | * Return: The pointer of the instance if found, or %NULL if not. | |
886 | * | |
887 | * Note that this function takes card->controls_rwsem lock internally. | |
888 | */ | |
889 | struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card, | |
890 | const struct snd_ctl_elem_id *id) | |
891 | { | |
892 | guard(rwsem_read)(&card->controls_rwsem); | |
893 | return snd_ctl_find_id_locked(card, id); | |
894 | } | |
895 | EXPORT_SYMBOL(snd_ctl_find_id); | |
896 | ||
897 | static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl, | |
898 | unsigned int cmd, void __user *arg) | |
899 | { | |
900 | struct snd_ctl_card_info *info __free(kfree) = NULL; | |
901 | ||
902 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
903 | if (! info) | |
904 | return -ENOMEM; | |
905 | scoped_guard(rwsem_read, &snd_ioctl_rwsem) { | |
906 | info->card = card->number; | |
907 | strscpy(info->id, card->id, sizeof(info->id)); | |
908 | strscpy(info->driver, card->driver, sizeof(info->driver)); | |
909 | strscpy(info->name, card->shortname, sizeof(info->name)); | |
910 | strscpy(info->longname, card->longname, sizeof(info->longname)); | |
911 | strscpy(info->mixername, card->mixername, sizeof(info->mixername)); | |
912 | strscpy(info->components, card->components, sizeof(info->components)); | |
913 | } | |
914 | if (copy_to_user(arg, info, sizeof(struct snd_ctl_card_info))) | |
915 | return -EFAULT; | |
916 | return 0; | |
917 | } | |
918 | ||
919 | static int snd_ctl_elem_list(struct snd_card *card, | |
920 | struct snd_ctl_elem_list *list) | |
921 | { | |
922 | struct snd_kcontrol *kctl; | |
923 | struct snd_ctl_elem_id id; | |
924 | unsigned int offset, space, jidx; | |
925 | ||
926 | offset = list->offset; | |
927 | space = list->space; | |
928 | ||
929 | guard(rwsem_read)(&card->controls_rwsem); | |
930 | list->count = card->controls_count; | |
931 | list->used = 0; | |
932 | if (!space) | |
933 | return 0; | |
934 | list_for_each_entry(kctl, &card->controls, list) { | |
935 | if (offset >= kctl->count) { | |
936 | offset -= kctl->count; | |
937 | continue; | |
938 | } | |
939 | for (jidx = offset; jidx < kctl->count; jidx++) { | |
940 | snd_ctl_build_ioff(&id, kctl, jidx); | |
941 | if (copy_to_user(list->pids + list->used, &id, sizeof(id))) | |
942 | return -EFAULT; | |
943 | list->used++; | |
944 | if (!--space) | |
945 | return 0; | |
946 | } | |
947 | offset = 0; | |
948 | } | |
949 | return 0; | |
950 | } | |
951 | ||
952 | static int snd_ctl_elem_list_user(struct snd_card *card, | |
953 | struct snd_ctl_elem_list __user *_list) | |
954 | { | |
955 | struct snd_ctl_elem_list list; | |
956 | int err; | |
957 | ||
958 | if (copy_from_user(&list, _list, sizeof(list))) | |
959 | return -EFAULT; | |
960 | err = snd_ctl_elem_list(card, &list); | |
961 | if (err) | |
962 | return err; | |
963 | if (copy_to_user(_list, &list, sizeof(list))) | |
964 | return -EFAULT; | |
965 | ||
966 | return 0; | |
967 | } | |
968 | ||
969 | /* Check whether the given kctl info is valid */ | |
970 | static int snd_ctl_check_elem_info(struct snd_card *card, | |
971 | const struct snd_ctl_elem_info *info) | |
972 | { | |
973 | static const unsigned int max_value_counts[] = { | |
974 | [SNDRV_CTL_ELEM_TYPE_BOOLEAN] = 128, | |
975 | [SNDRV_CTL_ELEM_TYPE_INTEGER] = 128, | |
976 | [SNDRV_CTL_ELEM_TYPE_ENUMERATED] = 128, | |
977 | [SNDRV_CTL_ELEM_TYPE_BYTES] = 512, | |
978 | [SNDRV_CTL_ELEM_TYPE_IEC958] = 1, | |
979 | [SNDRV_CTL_ELEM_TYPE_INTEGER64] = 64, | |
980 | }; | |
981 | ||
982 | if (info->type < SNDRV_CTL_ELEM_TYPE_BOOLEAN || | |
983 | info->type > SNDRV_CTL_ELEM_TYPE_INTEGER64) { | |
984 | if (card) | |
985 | dev_err(card->dev, | |
986 | "control %i:%i:%i:%s:%i: invalid type %d\n", | |
987 | info->id.iface, info->id.device, | |
988 | info->id.subdevice, info->id.name, | |
989 | info->id.index, info->type); | |
990 | return -EINVAL; | |
991 | } | |
992 | if (info->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED && | |
993 | info->value.enumerated.items == 0) { | |
994 | if (card) | |
995 | dev_err(card->dev, | |
996 | "control %i:%i:%i:%s:%i: zero enum items\n", | |
997 | info->id.iface, info->id.device, | |
998 | info->id.subdevice, info->id.name, | |
999 | info->id.index); | |
1000 | return -EINVAL; | |
1001 | } | |
1002 | if (info->count > max_value_counts[info->type]) { | |
1003 | if (card) | |
1004 | dev_err(card->dev, | |
1005 | "control %i:%i:%i:%s:%i: invalid count %d\n", | |
1006 | info->id.iface, info->id.device, | |
1007 | info->id.subdevice, info->id.name, | |
1008 | info->id.index, info->count); | |
1009 | return -EINVAL; | |
1010 | } | |
1011 | ||
1012 | return 0; | |
1013 | } | |
1014 | ||
1015 | /* The capacity of struct snd_ctl_elem_value.value.*/ | |
1016 | static const unsigned int value_sizes[] = { | |
1017 | [SNDRV_CTL_ELEM_TYPE_BOOLEAN] = sizeof(long), | |
1018 | [SNDRV_CTL_ELEM_TYPE_INTEGER] = sizeof(long), | |
1019 | [SNDRV_CTL_ELEM_TYPE_ENUMERATED] = sizeof(unsigned int), | |
1020 | [SNDRV_CTL_ELEM_TYPE_BYTES] = sizeof(unsigned char), | |
1021 | [SNDRV_CTL_ELEM_TYPE_IEC958] = sizeof(struct snd_aes_iec958), | |
1022 | [SNDRV_CTL_ELEM_TYPE_INTEGER64] = sizeof(long long), | |
1023 | }; | |
1024 | ||
1025 | /* fill the remaining snd_ctl_elem_value data with the given pattern */ | |
1026 | static void fill_remaining_elem_value(struct snd_ctl_elem_value *control, | |
1027 | struct snd_ctl_elem_info *info, | |
1028 | u32 pattern) | |
1029 | { | |
1030 | size_t offset = value_sizes[info->type] * info->count; | |
1031 | ||
1032 | offset = DIV_ROUND_UP(offset, sizeof(u32)); | |
1033 | memset32((u32 *)control->value.bytes.data + offset, pattern, | |
1034 | sizeof(control->value) / sizeof(u32) - offset); | |
1035 | } | |
1036 | ||
1037 | /* check whether the given integer ctl value is valid */ | |
1038 | static int sanity_check_int_value(struct snd_card *card, | |
1039 | const struct snd_ctl_elem_value *control, | |
1040 | const struct snd_ctl_elem_info *info, | |
1041 | int i, bool print_error) | |
1042 | { | |
1043 | long long lval, lmin, lmax, lstep; | |
1044 | u64 rem; | |
1045 | ||
1046 | switch (info->type) { | |
1047 | default: | |
1048 | case SNDRV_CTL_ELEM_TYPE_BOOLEAN: | |
1049 | lval = control->value.integer.value[i]; | |
1050 | lmin = 0; | |
1051 | lmax = 1; | |
1052 | lstep = 0; | |
1053 | break; | |
1054 | case SNDRV_CTL_ELEM_TYPE_INTEGER: | |
1055 | lval = control->value.integer.value[i]; | |
1056 | lmin = info->value.integer.min; | |
1057 | lmax = info->value.integer.max; | |
1058 | lstep = info->value.integer.step; | |
1059 | break; | |
1060 | case SNDRV_CTL_ELEM_TYPE_INTEGER64: | |
1061 | lval = control->value.integer64.value[i]; | |
1062 | lmin = info->value.integer64.min; | |
1063 | lmax = info->value.integer64.max; | |
1064 | lstep = info->value.integer64.step; | |
1065 | break; | |
1066 | case SNDRV_CTL_ELEM_TYPE_ENUMERATED: | |
1067 | lval = control->value.enumerated.item[i]; | |
1068 | lmin = 0; | |
1069 | lmax = info->value.enumerated.items - 1; | |
1070 | lstep = 0; | |
1071 | break; | |
1072 | } | |
1073 | ||
1074 | if (lval < lmin || lval > lmax) { | |
1075 | if (print_error) | |
1076 | dev_err(card->dev, | |
1077 | "control %i:%i:%i:%s:%i: value out of range %lld (%lld/%lld) at count %i\n", | |
1078 | control->id.iface, control->id.device, | |
1079 | control->id.subdevice, control->id.name, | |
1080 | control->id.index, lval, lmin, lmax, i); | |
1081 | return -EINVAL; | |
1082 | } | |
1083 | if (lstep) { | |
1084 | div64_u64_rem(lval, lstep, &rem); | |
1085 | if (rem) { | |
1086 | if (print_error) | |
1087 | dev_err(card->dev, | |
1088 | "control %i:%i:%i:%s:%i: unaligned value %lld (step %lld) at count %i\n", | |
1089 | control->id.iface, control->id.device, | |
1090 | control->id.subdevice, control->id.name, | |
1091 | control->id.index, lval, lstep, i); | |
1092 | return -EINVAL; | |
1093 | } | |
1094 | } | |
1095 | ||
1096 | return 0; | |
1097 | } | |
1098 | ||
1099 | /* check whether the all input values are valid for the given elem value */ | |
1100 | static int sanity_check_input_values(struct snd_card *card, | |
1101 | const struct snd_ctl_elem_value *control, | |
1102 | const struct snd_ctl_elem_info *info, | |
1103 | bool print_error) | |
1104 | { | |
1105 | int i, ret; | |
1106 | ||
1107 | switch (info->type) { | |
1108 | case SNDRV_CTL_ELEM_TYPE_BOOLEAN: | |
1109 | case SNDRV_CTL_ELEM_TYPE_INTEGER: | |
1110 | case SNDRV_CTL_ELEM_TYPE_INTEGER64: | |
1111 | case SNDRV_CTL_ELEM_TYPE_ENUMERATED: | |
1112 | for (i = 0; i < info->count; i++) { | |
1113 | ret = sanity_check_int_value(card, control, info, i, | |
1114 | print_error); | |
1115 | if (ret < 0) | |
1116 | return ret; | |
1117 | } | |
1118 | break; | |
1119 | default: | |
1120 | break; | |
1121 | } | |
1122 | ||
1123 | return 0; | |
1124 | } | |
1125 | ||
1126 | /* perform sanity checks to the given snd_ctl_elem_value object */ | |
1127 | static int sanity_check_elem_value(struct snd_card *card, | |
1128 | const struct snd_ctl_elem_value *control, | |
1129 | const struct snd_ctl_elem_info *info, | |
1130 | u32 pattern) | |
1131 | { | |
1132 | size_t offset; | |
1133 | int ret; | |
1134 | u32 *p; | |
1135 | ||
1136 | ret = sanity_check_input_values(card, control, info, true); | |
1137 | if (ret < 0) | |
1138 | return ret; | |
1139 | ||
1140 | /* check whether the remaining area kept untouched */ | |
1141 | offset = value_sizes[info->type] * info->count; | |
1142 | offset = DIV_ROUND_UP(offset, sizeof(u32)); | |
1143 | p = (u32 *)control->value.bytes.data + offset; | |
1144 | for (; offset < sizeof(control->value) / sizeof(u32); offset++, p++) { | |
1145 | if (*p != pattern) { | |
1146 | ret = -EINVAL; | |
1147 | break; | |
1148 | } | |
1149 | *p = 0; /* clear the checked area */ | |
1150 | } | |
1151 | ||
1152 | return ret; | |
1153 | } | |
1154 | ||
1155 | static int __snd_ctl_elem_info(struct snd_card *card, | |
1156 | struct snd_kcontrol *kctl, | |
1157 | struct snd_ctl_elem_info *info, | |
1158 | struct snd_ctl_file *ctl) | |
1159 | { | |
1160 | struct snd_kcontrol_volatile *vd; | |
1161 | unsigned int index_offset; | |
1162 | int result; | |
1163 | ||
1164 | #ifdef CONFIG_SND_DEBUG | |
1165 | info->access = 0; | |
1166 | #endif | |
1167 | result = snd_power_ref_and_wait(card); | |
1168 | if (!result) | |
1169 | result = kctl->info(kctl, info); | |
1170 | snd_power_unref(card); | |
1171 | if (result >= 0) { | |
1172 | snd_BUG_ON(info->access); | |
1173 | index_offset = snd_ctl_get_ioff(kctl, &info->id); | |
1174 | vd = &kctl->vd[index_offset]; | |
1175 | snd_ctl_build_ioff(&info->id, kctl, index_offset); | |
1176 | info->access = vd->access; | |
1177 | if (vd->owner) { | |
1178 | info->access |= SNDRV_CTL_ELEM_ACCESS_LOCK; | |
1179 | if (vd->owner == ctl) | |
1180 | info->access |= SNDRV_CTL_ELEM_ACCESS_OWNER; | |
1181 | info->owner = pid_vnr(vd->owner->pid); | |
1182 | } else { | |
1183 | info->owner = -1; | |
1184 | } | |
1185 | if (!snd_ctl_skip_validation(info) && | |
1186 | snd_ctl_check_elem_info(card, info) < 0) | |
1187 | result = -EINVAL; | |
1188 | } | |
1189 | return result; | |
1190 | } | |
1191 | ||
1192 | static int snd_ctl_elem_info(struct snd_ctl_file *ctl, | |
1193 | struct snd_ctl_elem_info *info) | |
1194 | { | |
1195 | struct snd_card *card = ctl->card; | |
1196 | struct snd_kcontrol *kctl; | |
1197 | ||
1198 | guard(rwsem_read)(&card->controls_rwsem); | |
1199 | kctl = snd_ctl_find_id_locked(card, &info->id); | |
1200 | if (!kctl) | |
1201 | return -ENOENT; | |
1202 | return __snd_ctl_elem_info(card, kctl, info, ctl); | |
1203 | } | |
1204 | ||
1205 | static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl, | |
1206 | struct snd_ctl_elem_info __user *_info) | |
1207 | { | |
1208 | struct snd_ctl_elem_info info; | |
1209 | int result; | |
1210 | ||
1211 | if (copy_from_user(&info, _info, sizeof(info))) | |
1212 | return -EFAULT; | |
1213 | result = snd_ctl_elem_info(ctl, &info); | |
1214 | if (result < 0) | |
1215 | return result; | |
1216 | /* drop internal access flags */ | |
1217 | info.access &= ~(SNDRV_CTL_ELEM_ACCESS_SKIP_CHECK| | |
1218 | SNDRV_CTL_ELEM_ACCESS_LED_MASK); | |
1219 | if (copy_to_user(_info, &info, sizeof(info))) | |
1220 | return -EFAULT; | |
1221 | return result; | |
1222 | } | |
1223 | ||
1224 | static int snd_ctl_elem_read(struct snd_card *card, | |
1225 | struct snd_ctl_elem_value *control) | |
1226 | { | |
1227 | struct snd_kcontrol *kctl; | |
1228 | struct snd_kcontrol_volatile *vd; | |
1229 | unsigned int index_offset; | |
1230 | struct snd_ctl_elem_info info; | |
1231 | const u32 pattern = 0xdeadbeef; | |
1232 | int ret; | |
1233 | ||
1234 | guard(rwsem_read)(&card->controls_rwsem); | |
1235 | kctl = snd_ctl_find_id_locked(card, &control->id); | |
1236 | if (!kctl) | |
1237 | return -ENOENT; | |
1238 | ||
1239 | index_offset = snd_ctl_get_ioff(kctl, &control->id); | |
1240 | vd = &kctl->vd[index_offset]; | |
1241 | if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_READ) || !kctl->get) | |
1242 | return -EPERM; | |
1243 | ||
1244 | snd_ctl_build_ioff(&control->id, kctl, index_offset); | |
1245 | ||
1246 | #ifdef CONFIG_SND_CTL_DEBUG | |
1247 | /* info is needed only for validation */ | |
1248 | memset(&info, 0, sizeof(info)); | |
1249 | info.id = control->id; | |
1250 | ret = __snd_ctl_elem_info(card, kctl, &info, NULL); | |
1251 | if (ret < 0) | |
1252 | return ret; | |
1253 | #endif | |
1254 | ||
1255 | if (!snd_ctl_skip_validation(&info)) | |
1256 | fill_remaining_elem_value(control, &info, pattern); | |
1257 | ret = snd_power_ref_and_wait(card); | |
1258 | if (!ret) | |
1259 | ret = kctl->get(kctl, control); | |
1260 | snd_power_unref(card); | |
1261 | if (ret < 0) | |
1262 | return ret; | |
1263 | if (!snd_ctl_skip_validation(&info) && | |
1264 | sanity_check_elem_value(card, control, &info, pattern) < 0) { | |
1265 | dev_err(card->dev, | |
1266 | "control %i:%i:%i:%s:%i: access overflow\n", | |
1267 | control->id.iface, control->id.device, | |
1268 | control->id.subdevice, control->id.name, | |
1269 | control->id.index); | |
1270 | return -EINVAL; | |
1271 | } | |
1272 | return 0; | |
1273 | } | |
1274 | ||
1275 | static int snd_ctl_elem_read_user(struct snd_card *card, | |
1276 | struct snd_ctl_elem_value __user *_control) | |
1277 | { | |
1278 | struct snd_ctl_elem_value *control; | |
1279 | int result; | |
1280 | ||
1281 | control = memdup_user(_control, sizeof(*control)); | |
1282 | if (IS_ERR(control)) | |
1283 | return PTR_ERR(control); | |
1284 | ||
1285 | result = snd_ctl_elem_read(card, control); | |
1286 | if (result < 0) | |
1287 | return result; | |
1288 | ||
1289 | if (copy_to_user(_control, control, sizeof(*control))) | |
1290 | return -EFAULT; | |
1291 | return result; | |
1292 | } | |
1293 | ||
1294 | static int snd_ctl_elem_write(struct snd_card *card, struct snd_ctl_file *file, | |
1295 | struct snd_ctl_elem_value *control) | |
1296 | { | |
1297 | struct snd_kcontrol *kctl; | |
1298 | struct snd_kcontrol_volatile *vd; | |
1299 | unsigned int index_offset; | |
1300 | int result; | |
1301 | ||
1302 | down_write(&card->controls_rwsem); | |
1303 | kctl = snd_ctl_find_id_locked(card, &control->id); | |
1304 | if (kctl == NULL) { | |
1305 | up_write(&card->controls_rwsem); | |
1306 | return -ENOENT; | |
1307 | } | |
1308 | ||
1309 | index_offset = snd_ctl_get_ioff(kctl, &control->id); | |
1310 | vd = &kctl->vd[index_offset]; | |
1311 | if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_WRITE) || kctl->put == NULL || | |
1312 | (file && vd->owner && vd->owner != file)) { | |
1313 | up_write(&card->controls_rwsem); | |
1314 | return -EPERM; | |
1315 | } | |
1316 | ||
1317 | snd_ctl_build_ioff(&control->id, kctl, index_offset); | |
1318 | result = snd_power_ref_and_wait(card); | |
1319 | /* validate input values */ | |
1320 | if (IS_ENABLED(CONFIG_SND_CTL_INPUT_VALIDATION) && !result) { | |
1321 | struct snd_ctl_elem_info info; | |
1322 | ||
1323 | memset(&info, 0, sizeof(info)); | |
1324 | info.id = control->id; | |
1325 | result = __snd_ctl_elem_info(card, kctl, &info, NULL); | |
1326 | if (!result) | |
1327 | result = sanity_check_input_values(card, control, &info, | |
1328 | false); | |
1329 | } | |
1330 | if (!result) | |
1331 | result = kctl->put(kctl, control); | |
1332 | snd_power_unref(card); | |
1333 | if (result < 0) { | |
1334 | up_write(&card->controls_rwsem); | |
1335 | return result; | |
1336 | } | |
1337 | ||
1338 | if (result > 0) { | |
1339 | downgrade_write(&card->controls_rwsem); | |
1340 | snd_ctl_notify_one(card, SNDRV_CTL_EVENT_MASK_VALUE, kctl, index_offset); | |
1341 | up_read(&card->controls_rwsem); | |
1342 | } else { | |
1343 | up_write(&card->controls_rwsem); | |
1344 | } | |
1345 | ||
1346 | return 0; | |
1347 | } | |
1348 | ||
1349 | static int snd_ctl_elem_write_user(struct snd_ctl_file *file, | |
1350 | struct snd_ctl_elem_value __user *_control) | |
1351 | { | |
1352 | struct snd_ctl_elem_value *control __free(kfree) = NULL; | |
1353 | struct snd_card *card; | |
1354 | int result; | |
1355 | ||
1356 | control = memdup_user(_control, sizeof(*control)); | |
1357 | if (IS_ERR(control)) | |
1358 | return PTR_ERR(no_free_ptr(control)); | |
1359 | ||
1360 | card = file->card; | |
1361 | result = snd_ctl_elem_write(card, file, control); | |
1362 | if (result < 0) | |
1363 | return result; | |
1364 | ||
1365 | if (copy_to_user(_control, control, sizeof(*control))) | |
1366 | return -EFAULT; | |
1367 | return result; | |
1368 | } | |
1369 | ||
1370 | static int snd_ctl_elem_lock(struct snd_ctl_file *file, | |
1371 | struct snd_ctl_elem_id __user *_id) | |
1372 | { | |
1373 | struct snd_card *card = file->card; | |
1374 | struct snd_ctl_elem_id id; | |
1375 | struct snd_kcontrol *kctl; | |
1376 | struct snd_kcontrol_volatile *vd; | |
1377 | ||
1378 | if (copy_from_user(&id, _id, sizeof(id))) | |
1379 | return -EFAULT; | |
1380 | guard(rwsem_write)(&card->controls_rwsem); | |
1381 | kctl = snd_ctl_find_id_locked(card, &id); | |
1382 | if (!kctl) | |
1383 | return -ENOENT; | |
1384 | vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)]; | |
1385 | if (vd->owner) | |
1386 | return -EBUSY; | |
1387 | vd->owner = file; | |
1388 | return 0; | |
1389 | } | |
1390 | ||
1391 | static int snd_ctl_elem_unlock(struct snd_ctl_file *file, | |
1392 | struct snd_ctl_elem_id __user *_id) | |
1393 | { | |
1394 | struct snd_card *card = file->card; | |
1395 | struct snd_ctl_elem_id id; | |
1396 | struct snd_kcontrol *kctl; | |
1397 | struct snd_kcontrol_volatile *vd; | |
1398 | ||
1399 | if (copy_from_user(&id, _id, sizeof(id))) | |
1400 | return -EFAULT; | |
1401 | guard(rwsem_write)(&card->controls_rwsem); | |
1402 | kctl = snd_ctl_find_id_locked(card, &id); | |
1403 | if (!kctl) | |
1404 | return -ENOENT; | |
1405 | vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)]; | |
1406 | if (!vd->owner) | |
1407 | return -EINVAL; | |
1408 | if (vd->owner != file) | |
1409 | return -EPERM; | |
1410 | vd->owner = NULL; | |
1411 | return 0; | |
1412 | } | |
1413 | ||
1414 | struct user_element { | |
1415 | struct snd_ctl_elem_info info; | |
1416 | struct snd_card *card; | |
1417 | char *elem_data; /* element data */ | |
1418 | unsigned long elem_data_size; /* size of element data in bytes */ | |
1419 | void *tlv_data; /* TLV data */ | |
1420 | unsigned long tlv_data_size; /* TLV data size */ | |
1421 | void *priv_data; /* private data (like strings for enumerated type) */ | |
1422 | }; | |
1423 | ||
1424 | // check whether the addition (in bytes) of user ctl element may overflow the limit. | |
1425 | static bool check_user_elem_overflow(struct snd_card *card, ssize_t add) | |
1426 | { | |
1427 | return (ssize_t)card->user_ctl_alloc_size + add > max_user_ctl_alloc_size; | |
1428 | } | |
1429 | ||
1430 | static int snd_ctl_elem_user_info(struct snd_kcontrol *kcontrol, | |
1431 | struct snd_ctl_elem_info *uinfo) | |
1432 | { | |
1433 | struct user_element *ue = kcontrol->private_data; | |
1434 | unsigned int offset; | |
1435 | ||
1436 | offset = snd_ctl_get_ioff(kcontrol, &uinfo->id); | |
1437 | *uinfo = ue->info; | |
1438 | snd_ctl_build_ioff(&uinfo->id, kcontrol, offset); | |
1439 | ||
1440 | return 0; | |
1441 | } | |
1442 | ||
1443 | static int snd_ctl_elem_user_enum_info(struct snd_kcontrol *kcontrol, | |
1444 | struct snd_ctl_elem_info *uinfo) | |
1445 | { | |
1446 | struct user_element *ue = kcontrol->private_data; | |
1447 | const char *names; | |
1448 | unsigned int item; | |
1449 | unsigned int offset; | |
1450 | ||
1451 | item = uinfo->value.enumerated.item; | |
1452 | ||
1453 | offset = snd_ctl_get_ioff(kcontrol, &uinfo->id); | |
1454 | *uinfo = ue->info; | |
1455 | snd_ctl_build_ioff(&uinfo->id, kcontrol, offset); | |
1456 | ||
1457 | item = min(item, uinfo->value.enumerated.items - 1); | |
1458 | uinfo->value.enumerated.item = item; | |
1459 | ||
1460 | names = ue->priv_data; | |
1461 | for (; item > 0; --item) | |
1462 | names += strlen(names) + 1; | |
1463 | strcpy(uinfo->value.enumerated.name, names); | |
1464 | ||
1465 | return 0; | |
1466 | } | |
1467 | ||
1468 | static int snd_ctl_elem_user_get(struct snd_kcontrol *kcontrol, | |
1469 | struct snd_ctl_elem_value *ucontrol) | |
1470 | { | |
1471 | struct user_element *ue = kcontrol->private_data; | |
1472 | unsigned int size = ue->elem_data_size; | |
1473 | char *src = ue->elem_data + | |
1474 | snd_ctl_get_ioff(kcontrol, &ucontrol->id) * size; | |
1475 | ||
1476 | memcpy(&ucontrol->value, src, size); | |
1477 | return 0; | |
1478 | } | |
1479 | ||
1480 | static int snd_ctl_elem_user_put(struct snd_kcontrol *kcontrol, | |
1481 | struct snd_ctl_elem_value *ucontrol) | |
1482 | { | |
1483 | int change; | |
1484 | struct user_element *ue = kcontrol->private_data; | |
1485 | unsigned int size = ue->elem_data_size; | |
1486 | char *dst = ue->elem_data + | |
1487 | snd_ctl_get_ioff(kcontrol, &ucontrol->id) * size; | |
1488 | ||
1489 | change = memcmp(&ucontrol->value, dst, size) != 0; | |
1490 | if (change) | |
1491 | memcpy(dst, &ucontrol->value, size); | |
1492 | return change; | |
1493 | } | |
1494 | ||
1495 | /* called in controls_rwsem write lock */ | |
1496 | static int replace_user_tlv(struct snd_kcontrol *kctl, unsigned int __user *buf, | |
1497 | unsigned int size) | |
1498 | { | |
1499 | struct user_element *ue = kctl->private_data; | |
1500 | unsigned int *container; | |
1501 | unsigned int mask = 0; | |
1502 | int i; | |
1503 | int change; | |
1504 | ||
1505 | lockdep_assert_held_write(&ue->card->controls_rwsem); | |
1506 | ||
1507 | if (size > 1024 * 128) /* sane value */ | |
1508 | return -EINVAL; | |
1509 | ||
1510 | // does the TLV size change cause overflow? | |
1511 | if (check_user_elem_overflow(ue->card, (ssize_t)(size - ue->tlv_data_size))) | |
1512 | return -ENOMEM; | |
1513 | ||
1514 | container = vmemdup_user(buf, size); | |
1515 | if (IS_ERR(container)) | |
1516 | return PTR_ERR(container); | |
1517 | ||
1518 | change = ue->tlv_data_size != size; | |
1519 | if (!change) | |
1520 | change = memcmp(ue->tlv_data, container, size) != 0; | |
1521 | if (!change) { | |
1522 | kvfree(container); | |
1523 | return 0; | |
1524 | } | |
1525 | ||
1526 | if (ue->tlv_data == NULL) { | |
1527 | /* Now TLV data is available. */ | |
1528 | for (i = 0; i < kctl->count; ++i) | |
1529 | kctl->vd[i].access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ; | |
1530 | mask = SNDRV_CTL_EVENT_MASK_INFO; | |
1531 | } else { | |
1532 | ue->card->user_ctl_alloc_size -= ue->tlv_data_size; | |
1533 | ue->tlv_data_size = 0; | |
1534 | kvfree(ue->tlv_data); | |
1535 | } | |
1536 | ||
1537 | ue->tlv_data = container; | |
1538 | ue->tlv_data_size = size; | |
1539 | // decremented at private_free. | |
1540 | ue->card->user_ctl_alloc_size += size; | |
1541 | ||
1542 | mask |= SNDRV_CTL_EVENT_MASK_TLV; | |
1543 | for (i = 0; i < kctl->count; ++i) | |
1544 | snd_ctl_notify_one(ue->card, mask, kctl, i); | |
1545 | ||
1546 | return change; | |
1547 | } | |
1548 | ||
1549 | static int read_user_tlv(struct snd_kcontrol *kctl, unsigned int __user *buf, | |
1550 | unsigned int size) | |
1551 | { | |
1552 | struct user_element *ue = kctl->private_data; | |
1553 | ||
1554 | if (ue->tlv_data_size == 0 || ue->tlv_data == NULL) | |
1555 | return -ENXIO; | |
1556 | ||
1557 | if (size < ue->tlv_data_size) | |
1558 | return -ENOSPC; | |
1559 | ||
1560 | if (copy_to_user(buf, ue->tlv_data, ue->tlv_data_size)) | |
1561 | return -EFAULT; | |
1562 | ||
1563 | return 0; | |
1564 | } | |
1565 | ||
1566 | static int snd_ctl_elem_user_tlv(struct snd_kcontrol *kctl, int op_flag, | |
1567 | unsigned int size, unsigned int __user *buf) | |
1568 | { | |
1569 | if (op_flag == SNDRV_CTL_TLV_OP_WRITE) | |
1570 | return replace_user_tlv(kctl, buf, size); | |
1571 | else | |
1572 | return read_user_tlv(kctl, buf, size); | |
1573 | } | |
1574 | ||
1575 | /* called in controls_rwsem write lock */ | |
1576 | static int snd_ctl_elem_init_enum_names(struct user_element *ue) | |
1577 | { | |
1578 | char *names, *p; | |
1579 | size_t buf_len, name_len; | |
1580 | unsigned int i; | |
1581 | const uintptr_t user_ptrval = ue->info.value.enumerated.names_ptr; | |
1582 | ||
1583 | lockdep_assert_held_write(&ue->card->controls_rwsem); | |
1584 | ||
1585 | buf_len = ue->info.value.enumerated.names_length; | |
1586 | if (buf_len > 64 * 1024) | |
1587 | return -EINVAL; | |
1588 | ||
1589 | if (check_user_elem_overflow(ue->card, buf_len)) | |
1590 | return -ENOMEM; | |
1591 | names = vmemdup_user((const void __user *)user_ptrval, buf_len); | |
1592 | if (IS_ERR(names)) | |
1593 | return PTR_ERR(names); | |
1594 | ||
1595 | /* check that there are enough valid names */ | |
1596 | p = names; | |
1597 | for (i = 0; i < ue->info.value.enumerated.items; ++i) { | |
1598 | name_len = strnlen(p, buf_len); | |
1599 | if (name_len == 0 || name_len >= 64 || name_len == buf_len) { | |
1600 | kvfree(names); | |
1601 | return -EINVAL; | |
1602 | } | |
1603 | p += name_len + 1; | |
1604 | buf_len -= name_len + 1; | |
1605 | } | |
1606 | ||
1607 | ue->priv_data = names; | |
1608 | ue->info.value.enumerated.names_ptr = 0; | |
1609 | // increment the allocation size; decremented again at private_free. | |
1610 | ue->card->user_ctl_alloc_size += ue->info.value.enumerated.names_length; | |
1611 | ||
1612 | return 0; | |
1613 | } | |
1614 | ||
1615 | static size_t compute_user_elem_size(size_t size, unsigned int count) | |
1616 | { | |
1617 | return sizeof(struct user_element) + size * count; | |
1618 | } | |
1619 | ||
1620 | static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol) | |
1621 | { | |
1622 | struct user_element *ue = kcontrol->private_data; | |
1623 | ||
1624 | // decrement the allocation size. | |
1625 | ue->card->user_ctl_alloc_size -= compute_user_elem_size(ue->elem_data_size, kcontrol->count); | |
1626 | ue->card->user_ctl_alloc_size -= ue->tlv_data_size; | |
1627 | if (ue->priv_data) | |
1628 | ue->card->user_ctl_alloc_size -= ue->info.value.enumerated.names_length; | |
1629 | ||
1630 | kvfree(ue->tlv_data); | |
1631 | kvfree(ue->priv_data); | |
1632 | kfree(ue); | |
1633 | } | |
1634 | ||
1635 | static int snd_ctl_elem_add(struct snd_ctl_file *file, | |
1636 | struct snd_ctl_elem_info *info, int replace) | |
1637 | { | |
1638 | struct snd_card *card = file->card; | |
1639 | struct snd_kcontrol *kctl; | |
1640 | unsigned int count; | |
1641 | unsigned int access; | |
1642 | long private_size; | |
1643 | size_t alloc_size; | |
1644 | struct user_element *ue; | |
1645 | unsigned int offset; | |
1646 | int err; | |
1647 | ||
1648 | if (!*info->id.name) | |
1649 | return -EINVAL; | |
1650 | if (strnlen(info->id.name, sizeof(info->id.name)) >= sizeof(info->id.name)) | |
1651 | return -EINVAL; | |
1652 | ||
1653 | /* Delete a control to replace them if needed. */ | |
1654 | if (replace) { | |
1655 | info->id.numid = 0; | |
1656 | err = snd_ctl_remove_user_ctl(file, &info->id); | |
1657 | if (err) | |
1658 | return err; | |
1659 | } | |
1660 | ||
1661 | /* Check the number of elements for this userspace control. */ | |
1662 | count = info->owner; | |
1663 | if (count == 0) | |
1664 | count = 1; | |
1665 | ||
1666 | /* Arrange access permissions if needed. */ | |
1667 | access = info->access; | |
1668 | if (access == 0) | |
1669 | access = SNDRV_CTL_ELEM_ACCESS_READWRITE; | |
1670 | access &= (SNDRV_CTL_ELEM_ACCESS_READWRITE | | |
1671 | SNDRV_CTL_ELEM_ACCESS_INACTIVE | | |
1672 | SNDRV_CTL_ELEM_ACCESS_TLV_WRITE); | |
1673 | ||
1674 | /* In initial state, nothing is available as TLV container. */ | |
1675 | if (access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE) | |
1676 | access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK; | |
1677 | access |= SNDRV_CTL_ELEM_ACCESS_USER; | |
1678 | ||
1679 | /* | |
1680 | * Check information and calculate the size of data specific to | |
1681 | * this userspace control. | |
1682 | */ | |
1683 | /* pass NULL to card for suppressing error messages */ | |
1684 | err = snd_ctl_check_elem_info(NULL, info); | |
1685 | if (err < 0) | |
1686 | return err; | |
1687 | /* user-space control doesn't allow zero-size data */ | |
1688 | if (info->count < 1) | |
1689 | return -EINVAL; | |
1690 | private_size = value_sizes[info->type] * info->count; | |
1691 | alloc_size = compute_user_elem_size(private_size, count); | |
1692 | ||
1693 | guard(rwsem_write)(&card->controls_rwsem); | |
1694 | if (check_user_elem_overflow(card, alloc_size)) | |
1695 | return -ENOMEM; | |
1696 | ||
1697 | /* | |
1698 | * Keep memory object for this userspace control. After passing this | |
1699 | * code block, the instance should be freed by snd_ctl_free_one(). | |
1700 | * | |
1701 | * Note that these elements in this control are locked. | |
1702 | */ | |
1703 | err = snd_ctl_new(&kctl, count, access, file); | |
1704 | if (err < 0) | |
1705 | return err; | |
1706 | memcpy(&kctl->id, &info->id, sizeof(kctl->id)); | |
1707 | ue = kzalloc(alloc_size, GFP_KERNEL); | |
1708 | if (!ue) { | |
1709 | kfree(kctl); | |
1710 | return -ENOMEM; | |
1711 | } | |
1712 | kctl->private_data = ue; | |
1713 | kctl->private_free = snd_ctl_elem_user_free; | |
1714 | ||
1715 | // increment the allocated size; decremented again at private_free. | |
1716 | card->user_ctl_alloc_size += alloc_size; | |
1717 | ||
1718 | /* Set private data for this userspace control. */ | |
1719 | ue->card = card; | |
1720 | ue->info = *info; | |
1721 | ue->info.access = 0; | |
1722 | ue->elem_data = (char *)ue + sizeof(*ue); | |
1723 | ue->elem_data_size = private_size; | |
1724 | if (ue->info.type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) { | |
1725 | err = snd_ctl_elem_init_enum_names(ue); | |
1726 | if (err < 0) { | |
1727 | snd_ctl_free_one(kctl); | |
1728 | return err; | |
1729 | } | |
1730 | } | |
1731 | ||
1732 | /* Set callback functions. */ | |
1733 | if (info->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) | |
1734 | kctl->info = snd_ctl_elem_user_enum_info; | |
1735 | else | |
1736 | kctl->info = snd_ctl_elem_user_info; | |
1737 | if (access & SNDRV_CTL_ELEM_ACCESS_READ) | |
1738 | kctl->get = snd_ctl_elem_user_get; | |
1739 | if (access & SNDRV_CTL_ELEM_ACCESS_WRITE) | |
1740 | kctl->put = snd_ctl_elem_user_put; | |
1741 | if (access & SNDRV_CTL_ELEM_ACCESS_TLV_WRITE) | |
1742 | kctl->tlv.c = snd_ctl_elem_user_tlv; | |
1743 | ||
1744 | /* This function manage to free the instance on failure. */ | |
1745 | err = __snd_ctl_add_replace(card, kctl, CTL_ADD_EXCLUSIVE); | |
1746 | if (err < 0) { | |
1747 | snd_ctl_free_one(kctl); | |
1748 | return err; | |
1749 | } | |
1750 | offset = snd_ctl_get_ioff(kctl, &info->id); | |
1751 | snd_ctl_build_ioff(&info->id, kctl, offset); | |
1752 | /* | |
1753 | * Here we cannot fill any field for the number of elements added by | |
1754 | * this operation because there're no specific fields. The usage of | |
1755 | * 'owner' field for this purpose may cause any bugs to userspace | |
1756 | * applications because the field originally means PID of a process | |
1757 | * which locks the element. | |
1758 | */ | |
1759 | return 0; | |
1760 | } | |
1761 | ||
1762 | static int snd_ctl_elem_add_user(struct snd_ctl_file *file, | |
1763 | struct snd_ctl_elem_info __user *_info, int replace) | |
1764 | { | |
1765 | struct snd_ctl_elem_info info; | |
1766 | int err; | |
1767 | ||
1768 | if (copy_from_user(&info, _info, sizeof(info))) | |
1769 | return -EFAULT; | |
1770 | err = snd_ctl_elem_add(file, &info, replace); | |
1771 | if (err < 0) | |
1772 | return err; | |
1773 | if (copy_to_user(_info, &info, sizeof(info))) { | |
1774 | snd_ctl_remove_user_ctl(file, &info.id); | |
1775 | return -EFAULT; | |
1776 | } | |
1777 | ||
1778 | return 0; | |
1779 | } | |
1780 | ||
1781 | static int snd_ctl_elem_remove(struct snd_ctl_file *file, | |
1782 | struct snd_ctl_elem_id __user *_id) | |
1783 | { | |
1784 | struct snd_ctl_elem_id id; | |
1785 | ||
1786 | if (copy_from_user(&id, _id, sizeof(id))) | |
1787 | return -EFAULT; | |
1788 | return snd_ctl_remove_user_ctl(file, &id); | |
1789 | } | |
1790 | ||
1791 | static int snd_ctl_subscribe_events(struct snd_ctl_file *file, int __user *ptr) | |
1792 | { | |
1793 | int subscribe; | |
1794 | if (get_user(subscribe, ptr)) | |
1795 | return -EFAULT; | |
1796 | if (subscribe < 0) { | |
1797 | subscribe = file->subscribed; | |
1798 | if (put_user(subscribe, ptr)) | |
1799 | return -EFAULT; | |
1800 | return 0; | |
1801 | } | |
1802 | if (subscribe) { | |
1803 | file->subscribed = 1; | |
1804 | return 0; | |
1805 | } else if (file->subscribed) { | |
1806 | snd_ctl_empty_read_queue(file); | |
1807 | file->subscribed = 0; | |
1808 | } | |
1809 | return 0; | |
1810 | } | |
1811 | ||
1812 | static int call_tlv_handler(struct snd_ctl_file *file, int op_flag, | |
1813 | struct snd_kcontrol *kctl, | |
1814 | struct snd_ctl_elem_id *id, | |
1815 | unsigned int __user *buf, unsigned int size) | |
1816 | { | |
1817 | static const struct { | |
1818 | int op; | |
1819 | int perm; | |
1820 | } pairs[] = { | |
1821 | {SNDRV_CTL_TLV_OP_READ, SNDRV_CTL_ELEM_ACCESS_TLV_READ}, | |
1822 | {SNDRV_CTL_TLV_OP_WRITE, SNDRV_CTL_ELEM_ACCESS_TLV_WRITE}, | |
1823 | {SNDRV_CTL_TLV_OP_CMD, SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND}, | |
1824 | }; | |
1825 | struct snd_kcontrol_volatile *vd = &kctl->vd[snd_ctl_get_ioff(kctl, id)]; | |
1826 | int i, ret; | |
1827 | ||
1828 | /* Check support of the request for this element. */ | |
1829 | for (i = 0; i < ARRAY_SIZE(pairs); ++i) { | |
1830 | if (op_flag == pairs[i].op && (vd->access & pairs[i].perm)) | |
1831 | break; | |
1832 | } | |
1833 | if (i == ARRAY_SIZE(pairs)) | |
1834 | return -ENXIO; | |
1835 | ||
1836 | if (kctl->tlv.c == NULL) | |
1837 | return -ENXIO; | |
1838 | ||
1839 | /* Write and command operations are not allowed for locked element. */ | |
1840 | if (op_flag != SNDRV_CTL_TLV_OP_READ && | |
1841 | vd->owner != NULL && vd->owner != file) | |
1842 | return -EPERM; | |
1843 | ||
1844 | ret = snd_power_ref_and_wait(file->card); | |
1845 | if (!ret) | |
1846 | ret = kctl->tlv.c(kctl, op_flag, size, buf); | |
1847 | snd_power_unref(file->card); | |
1848 | return ret; | |
1849 | } | |
1850 | ||
1851 | static int read_tlv_buf(struct snd_kcontrol *kctl, struct snd_ctl_elem_id *id, | |
1852 | unsigned int __user *buf, unsigned int size) | |
1853 | { | |
1854 | struct snd_kcontrol_volatile *vd = &kctl->vd[snd_ctl_get_ioff(kctl, id)]; | |
1855 | unsigned int len; | |
1856 | ||
1857 | if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_READ)) | |
1858 | return -ENXIO; | |
1859 | ||
1860 | if (kctl->tlv.p == NULL) | |
1861 | return -ENXIO; | |
1862 | ||
1863 | len = sizeof(unsigned int) * 2 + kctl->tlv.p[1]; | |
1864 | if (size < len) | |
1865 | return -ENOMEM; | |
1866 | ||
1867 | if (copy_to_user(buf, kctl->tlv.p, len)) | |
1868 | return -EFAULT; | |
1869 | ||
1870 | return 0; | |
1871 | } | |
1872 | ||
1873 | static int snd_ctl_tlv_ioctl(struct snd_ctl_file *file, | |
1874 | struct snd_ctl_tlv __user *buf, | |
1875 | int op_flag) | |
1876 | { | |
1877 | struct snd_ctl_tlv header; | |
1878 | unsigned int __user *container; | |
1879 | unsigned int container_size; | |
1880 | struct snd_kcontrol *kctl; | |
1881 | struct snd_ctl_elem_id id; | |
1882 | struct snd_kcontrol_volatile *vd; | |
1883 | ||
1884 | lockdep_assert_held(&file->card->controls_rwsem); | |
1885 | ||
1886 | if (copy_from_user(&header, buf, sizeof(header))) | |
1887 | return -EFAULT; | |
1888 | ||
1889 | /* In design of control core, numerical ID starts at 1. */ | |
1890 | if (header.numid == 0) | |
1891 | return -EINVAL; | |
1892 | ||
1893 | /* At least, container should include type and length fields. */ | |
1894 | if (header.length < sizeof(unsigned int) * 2) | |
1895 | return -EINVAL; | |
1896 | container_size = header.length; | |
1897 | container = buf->tlv; | |
1898 | ||
1899 | kctl = snd_ctl_find_numid_locked(file->card, header.numid); | |
1900 | if (kctl == NULL) | |
1901 | return -ENOENT; | |
1902 | ||
1903 | /* Calculate index of the element in this set. */ | |
1904 | id = kctl->id; | |
1905 | snd_ctl_build_ioff(&id, kctl, header.numid - id.numid); | |
1906 | vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)]; | |
1907 | ||
1908 | if (vd->access & SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK) { | |
1909 | return call_tlv_handler(file, op_flag, kctl, &id, container, | |
1910 | container_size); | |
1911 | } else { | |
1912 | if (op_flag == SNDRV_CTL_TLV_OP_READ) { | |
1913 | return read_tlv_buf(kctl, &id, container, | |
1914 | container_size); | |
1915 | } | |
1916 | } | |
1917 | ||
1918 | /* Not supported. */ | |
1919 | return -ENXIO; | |
1920 | } | |
1921 | ||
1922 | static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg) | |
1923 | { | |
1924 | struct snd_ctl_file *ctl; | |
1925 | struct snd_card *card; | |
1926 | struct snd_kctl_ioctl *p; | |
1927 | void __user *argp = (void __user *)arg; | |
1928 | int __user *ip = argp; | |
1929 | int err; | |
1930 | ||
1931 | ctl = file->private_data; | |
1932 | card = ctl->card; | |
1933 | if (snd_BUG_ON(!card)) | |
1934 | return -ENXIO; | |
1935 | switch (cmd) { | |
1936 | case SNDRV_CTL_IOCTL_PVERSION: | |
1937 | return put_user(SNDRV_CTL_VERSION, ip) ? -EFAULT : 0; | |
1938 | case SNDRV_CTL_IOCTL_CARD_INFO: | |
1939 | return snd_ctl_card_info(card, ctl, cmd, argp); | |
1940 | case SNDRV_CTL_IOCTL_ELEM_LIST: | |
1941 | return snd_ctl_elem_list_user(card, argp); | |
1942 | case SNDRV_CTL_IOCTL_ELEM_INFO: | |
1943 | return snd_ctl_elem_info_user(ctl, argp); | |
1944 | case SNDRV_CTL_IOCTL_ELEM_READ: | |
1945 | return snd_ctl_elem_read_user(card, argp); | |
1946 | case SNDRV_CTL_IOCTL_ELEM_WRITE: | |
1947 | return snd_ctl_elem_write_user(ctl, argp); | |
1948 | case SNDRV_CTL_IOCTL_ELEM_LOCK: | |
1949 | return snd_ctl_elem_lock(ctl, argp); | |
1950 | case SNDRV_CTL_IOCTL_ELEM_UNLOCK: | |
1951 | return snd_ctl_elem_unlock(ctl, argp); | |
1952 | case SNDRV_CTL_IOCTL_ELEM_ADD: | |
1953 | return snd_ctl_elem_add_user(ctl, argp, 0); | |
1954 | case SNDRV_CTL_IOCTL_ELEM_REPLACE: | |
1955 | return snd_ctl_elem_add_user(ctl, argp, 1); | |
1956 | case SNDRV_CTL_IOCTL_ELEM_REMOVE: | |
1957 | return snd_ctl_elem_remove(ctl, argp); | |
1958 | case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS: | |
1959 | return snd_ctl_subscribe_events(ctl, ip); | |
1960 | case SNDRV_CTL_IOCTL_TLV_READ: | |
1961 | scoped_guard(rwsem_read, &ctl->card->controls_rwsem) | |
1962 | err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_READ); | |
1963 | return err; | |
1964 | case SNDRV_CTL_IOCTL_TLV_WRITE: | |
1965 | scoped_guard(rwsem_write, &ctl->card->controls_rwsem) | |
1966 | err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_WRITE); | |
1967 | return err; | |
1968 | case SNDRV_CTL_IOCTL_TLV_COMMAND: | |
1969 | scoped_guard(rwsem_write, &ctl->card->controls_rwsem) | |
1970 | err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_CMD); | |
1971 | return err; | |
1972 | case SNDRV_CTL_IOCTL_POWER: | |
1973 | return -ENOPROTOOPT; | |
1974 | case SNDRV_CTL_IOCTL_POWER_STATE: | |
1975 | return put_user(SNDRV_CTL_POWER_D0, ip) ? -EFAULT : 0; | |
1976 | } | |
1977 | ||
1978 | guard(rwsem_read)(&snd_ioctl_rwsem); | |
1979 | list_for_each_entry(p, &snd_control_ioctls, list) { | |
1980 | err = p->fioctl(card, ctl, cmd, arg); | |
1981 | if (err != -ENOIOCTLCMD) | |
1982 | return err; | |
1983 | } | |
1984 | dev_dbg(card->dev, "unknown ioctl = 0x%x\n", cmd); | |
1985 | return -ENOTTY; | |
1986 | } | |
1987 | ||
1988 | static ssize_t snd_ctl_read(struct file *file, char __user *buffer, | |
1989 | size_t count, loff_t * offset) | |
1990 | { | |
1991 | struct snd_ctl_file *ctl; | |
1992 | int err = 0; | |
1993 | ssize_t result = 0; | |
1994 | ||
1995 | ctl = file->private_data; | |
1996 | if (snd_BUG_ON(!ctl || !ctl->card)) | |
1997 | return -ENXIO; | |
1998 | if (!ctl->subscribed) | |
1999 | return -EBADFD; | |
2000 | if (count < sizeof(struct snd_ctl_event)) | |
2001 | return -EINVAL; | |
2002 | spin_lock_irq(&ctl->read_lock); | |
2003 | while (count >= sizeof(struct snd_ctl_event)) { | |
2004 | struct snd_ctl_event ev; | |
2005 | struct snd_kctl_event *kev; | |
2006 | while (list_empty(&ctl->events)) { | |
2007 | wait_queue_entry_t wait; | |
2008 | if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) { | |
2009 | err = -EAGAIN; | |
2010 | goto __end_lock; | |
2011 | } | |
2012 | init_waitqueue_entry(&wait, current); | |
2013 | add_wait_queue(&ctl->change_sleep, &wait); | |
2014 | set_current_state(TASK_INTERRUPTIBLE); | |
2015 | spin_unlock_irq(&ctl->read_lock); | |
2016 | schedule(); | |
2017 | remove_wait_queue(&ctl->change_sleep, &wait); | |
2018 | if (ctl->card->shutdown) | |
2019 | return -ENODEV; | |
2020 | if (signal_pending(current)) | |
2021 | return -ERESTARTSYS; | |
2022 | spin_lock_irq(&ctl->read_lock); | |
2023 | } | |
2024 | kev = snd_kctl_event(ctl->events.next); | |
2025 | ev.type = SNDRV_CTL_EVENT_ELEM; | |
2026 | ev.data.elem.mask = kev->mask; | |
2027 | ev.data.elem.id = kev->id; | |
2028 | list_del(&kev->list); | |
2029 | spin_unlock_irq(&ctl->read_lock); | |
2030 | kfree(kev); | |
2031 | if (copy_to_user(buffer, &ev, sizeof(struct snd_ctl_event))) { | |
2032 | err = -EFAULT; | |
2033 | goto __end; | |
2034 | } | |
2035 | spin_lock_irq(&ctl->read_lock); | |
2036 | buffer += sizeof(struct snd_ctl_event); | |
2037 | count -= sizeof(struct snd_ctl_event); | |
2038 | result += sizeof(struct snd_ctl_event); | |
2039 | } | |
2040 | __end_lock: | |
2041 | spin_unlock_irq(&ctl->read_lock); | |
2042 | __end: | |
2043 | return result > 0 ? result : err; | |
2044 | } | |
2045 | ||
2046 | static __poll_t snd_ctl_poll(struct file *file, poll_table * wait) | |
2047 | { | |
2048 | __poll_t mask; | |
2049 | struct snd_ctl_file *ctl; | |
2050 | ||
2051 | ctl = file->private_data; | |
2052 | if (!ctl->subscribed) | |
2053 | return 0; | |
2054 | poll_wait(file, &ctl->change_sleep, wait); | |
2055 | ||
2056 | mask = 0; | |
2057 | if (!list_empty(&ctl->events)) | |
2058 | mask |= EPOLLIN | EPOLLRDNORM; | |
2059 | ||
2060 | return mask; | |
2061 | } | |
2062 | ||
2063 | /* | |
2064 | * register the device-specific control-ioctls. | |
2065 | * called from each device manager like pcm.c, hwdep.c, etc. | |
2066 | */ | |
2067 | static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head *lists) | |
2068 | { | |
2069 | struct snd_kctl_ioctl *pn; | |
2070 | ||
2071 | pn = kzalloc(sizeof(struct snd_kctl_ioctl), GFP_KERNEL); | |
2072 | if (pn == NULL) | |
2073 | return -ENOMEM; | |
2074 | pn->fioctl = fcn; | |
2075 | guard(rwsem_write)(&snd_ioctl_rwsem); | |
2076 | list_add_tail(&pn->list, lists); | |
2077 | return 0; | |
2078 | } | |
2079 | ||
2080 | /** | |
2081 | * snd_ctl_register_ioctl - register the device-specific control-ioctls | |
2082 | * @fcn: ioctl callback function | |
2083 | * | |
2084 | * called from each device manager like pcm.c, hwdep.c, etc. | |
2085 | * | |
2086 | * Return: zero if successful, or a negative error code | |
2087 | */ | |
2088 | int snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn) | |
2089 | { | |
2090 | return _snd_ctl_register_ioctl(fcn, &snd_control_ioctls); | |
2091 | } | |
2092 | EXPORT_SYMBOL(snd_ctl_register_ioctl); | |
2093 | ||
2094 | #ifdef CONFIG_COMPAT | |
2095 | /** | |
2096 | * snd_ctl_register_ioctl_compat - register the device-specific 32bit compat | |
2097 | * control-ioctls | |
2098 | * @fcn: ioctl callback function | |
2099 | * | |
2100 | * Return: zero if successful, or a negative error code | |
2101 | */ | |
2102 | int snd_ctl_register_ioctl_compat(snd_kctl_ioctl_func_t fcn) | |
2103 | { | |
2104 | return _snd_ctl_register_ioctl(fcn, &snd_control_compat_ioctls); | |
2105 | } | |
2106 | EXPORT_SYMBOL(snd_ctl_register_ioctl_compat); | |
2107 | #endif | |
2108 | ||
2109 | /* | |
2110 | * de-register the device-specific control-ioctls. | |
2111 | */ | |
2112 | static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn, | |
2113 | struct list_head *lists) | |
2114 | { | |
2115 | struct snd_kctl_ioctl *p; | |
2116 | ||
2117 | if (snd_BUG_ON(!fcn)) | |
2118 | return -EINVAL; | |
2119 | guard(rwsem_write)(&snd_ioctl_rwsem); | |
2120 | list_for_each_entry(p, lists, list) { | |
2121 | if (p->fioctl == fcn) { | |
2122 | list_del(&p->list); | |
2123 | kfree(p); | |
2124 | return 0; | |
2125 | } | |
2126 | } | |
2127 | snd_BUG(); | |
2128 | return -EINVAL; | |
2129 | } | |
2130 | ||
2131 | /** | |
2132 | * snd_ctl_unregister_ioctl - de-register the device-specific control-ioctls | |
2133 | * @fcn: ioctl callback function to unregister | |
2134 | * | |
2135 | * Return: zero if successful, or a negative error code | |
2136 | */ | |
2137 | int snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn) | |
2138 | { | |
2139 | return _snd_ctl_unregister_ioctl(fcn, &snd_control_ioctls); | |
2140 | } | |
2141 | EXPORT_SYMBOL(snd_ctl_unregister_ioctl); | |
2142 | ||
2143 | #ifdef CONFIG_COMPAT | |
2144 | /** | |
2145 | * snd_ctl_unregister_ioctl_compat - de-register the device-specific compat | |
2146 | * 32bit control-ioctls | |
2147 | * @fcn: ioctl callback function to unregister | |
2148 | * | |
2149 | * Return: zero if successful, or a negative error code | |
2150 | */ | |
2151 | int snd_ctl_unregister_ioctl_compat(snd_kctl_ioctl_func_t fcn) | |
2152 | { | |
2153 | return _snd_ctl_unregister_ioctl(fcn, &snd_control_compat_ioctls); | |
2154 | } | |
2155 | EXPORT_SYMBOL(snd_ctl_unregister_ioctl_compat); | |
2156 | #endif | |
2157 | ||
2158 | static int snd_ctl_fasync(int fd, struct file * file, int on) | |
2159 | { | |
2160 | struct snd_ctl_file *ctl; | |
2161 | ||
2162 | ctl = file->private_data; | |
2163 | return snd_fasync_helper(fd, file, on, &ctl->fasync); | |
2164 | } | |
2165 | ||
2166 | /* return the preferred subdevice number if already assigned; | |
2167 | * otherwise return -1 | |
2168 | */ | |
2169 | int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type) | |
2170 | { | |
2171 | struct snd_ctl_file *kctl; | |
2172 | int subdevice = -1; | |
2173 | ||
2174 | guard(read_lock_irqsave)(&card->ctl_files_rwlock); | |
2175 | list_for_each_entry(kctl, &card->ctl_files, list) { | |
2176 | if (kctl->pid == task_pid(current)) { | |
2177 | subdevice = kctl->preferred_subdevice[type]; | |
2178 | if (subdevice != -1) | |
2179 | break; | |
2180 | } | |
2181 | } | |
2182 | return subdevice; | |
2183 | } | |
2184 | EXPORT_SYMBOL_GPL(snd_ctl_get_preferred_subdevice); | |
2185 | ||
2186 | /* | |
2187 | * ioctl32 compat | |
2188 | */ | |
2189 | #ifdef CONFIG_COMPAT | |
2190 | #include "control_compat.c" | |
2191 | #else | |
2192 | #define snd_ctl_ioctl_compat NULL | |
2193 | #endif | |
2194 | ||
2195 | /* | |
2196 | * control layers (audio LED etc.) | |
2197 | */ | |
2198 | ||
2199 | /** | |
2200 | * snd_ctl_request_layer - request to use the layer | |
2201 | * @module_name: Name of the kernel module (NULL == build-in) | |
2202 | * | |
2203 | * Return: zero if successful, or an error code when the module cannot be loaded | |
2204 | */ | |
2205 | int snd_ctl_request_layer(const char *module_name) | |
2206 | { | |
2207 | struct snd_ctl_layer_ops *lops; | |
2208 | ||
2209 | if (module_name == NULL) | |
2210 | return 0; | |
2211 | scoped_guard(rwsem_read, &snd_ctl_layer_rwsem) { | |
2212 | for (lops = snd_ctl_layer; lops; lops = lops->next) | |
2213 | if (strcmp(lops->module_name, module_name) == 0) | |
2214 | return 0; | |
2215 | } | |
2216 | return request_module(module_name); | |
2217 | } | |
2218 | EXPORT_SYMBOL_GPL(snd_ctl_request_layer); | |
2219 | ||
2220 | /** | |
2221 | * snd_ctl_register_layer - register new control layer | |
2222 | * @lops: operation structure | |
2223 | * | |
2224 | * The new layer can track all control elements and do additional | |
2225 | * operations on top (like audio LED handling). | |
2226 | */ | |
2227 | void snd_ctl_register_layer(struct snd_ctl_layer_ops *lops) | |
2228 | { | |
2229 | struct snd_card *card; | |
2230 | int card_number; | |
2231 | ||
2232 | scoped_guard(rwsem_write, &snd_ctl_layer_rwsem) { | |
2233 | lops->next = snd_ctl_layer; | |
2234 | snd_ctl_layer = lops; | |
2235 | } | |
2236 | for (card_number = 0; card_number < SNDRV_CARDS; card_number++) { | |
2237 | card = snd_card_ref(card_number); | |
2238 | if (card) { | |
2239 | scoped_guard(rwsem_read, &card->controls_rwsem) | |
2240 | lops->lregister(card); | |
2241 | snd_card_unref(card); | |
2242 | } | |
2243 | } | |
2244 | } | |
2245 | EXPORT_SYMBOL_GPL(snd_ctl_register_layer); | |
2246 | ||
2247 | /** | |
2248 | * snd_ctl_disconnect_layer - disconnect control layer | |
2249 | * @lops: operation structure | |
2250 | * | |
2251 | * It is expected that the information about tracked cards | |
2252 | * is freed before this call (the disconnect callback is | |
2253 | * not called here). | |
2254 | */ | |
2255 | void snd_ctl_disconnect_layer(struct snd_ctl_layer_ops *lops) | |
2256 | { | |
2257 | struct snd_ctl_layer_ops *lops2, *prev_lops2; | |
2258 | ||
2259 | guard(rwsem_write)(&snd_ctl_layer_rwsem); | |
2260 | for (lops2 = snd_ctl_layer, prev_lops2 = NULL; lops2; lops2 = lops2->next) { | |
2261 | if (lops2 == lops) { | |
2262 | if (!prev_lops2) | |
2263 | snd_ctl_layer = lops->next; | |
2264 | else | |
2265 | prev_lops2->next = lops->next; | |
2266 | break; | |
2267 | } | |
2268 | prev_lops2 = lops2; | |
2269 | } | |
2270 | } | |
2271 | EXPORT_SYMBOL_GPL(snd_ctl_disconnect_layer); | |
2272 | ||
2273 | /* | |
2274 | * INIT PART | |
2275 | */ | |
2276 | ||
2277 | static const struct file_operations snd_ctl_f_ops = | |
2278 | { | |
2279 | .owner = THIS_MODULE, | |
2280 | .read = snd_ctl_read, | |
2281 | .open = snd_ctl_open, | |
2282 | .release = snd_ctl_release, | |
2283 | .llseek = no_llseek, | |
2284 | .poll = snd_ctl_poll, | |
2285 | .unlocked_ioctl = snd_ctl_ioctl, | |
2286 | .compat_ioctl = snd_ctl_ioctl_compat, | |
2287 | .fasync = snd_ctl_fasync, | |
2288 | }; | |
2289 | ||
2290 | /* call lops under rwsems; called from snd_ctl_dev_*() below() */ | |
2291 | #define call_snd_ctl_lops(_card, _op) \ | |
2292 | do { \ | |
2293 | struct snd_ctl_layer_ops *lops; \ | |
2294 | guard(rwsem_read)(&(_card)->controls_rwsem); \ | |
2295 | guard(rwsem_read)(&snd_ctl_layer_rwsem); \ | |
2296 | for (lops = snd_ctl_layer; lops; lops = lops->next) \ | |
2297 | lops->_op(_card); \ | |
2298 | } while (0) | |
2299 | ||
2300 | /* | |
2301 | * registration of the control device | |
2302 | */ | |
2303 | static int snd_ctl_dev_register(struct snd_device *device) | |
2304 | { | |
2305 | struct snd_card *card = device->device_data; | |
2306 | int err; | |
2307 | ||
2308 | err = snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1, | |
2309 | &snd_ctl_f_ops, card, card->ctl_dev); | |
2310 | if (err < 0) | |
2311 | return err; | |
2312 | call_snd_ctl_lops(card, lregister); | |
2313 | return 0; | |
2314 | } | |
2315 | ||
2316 | /* | |
2317 | * disconnection of the control device | |
2318 | */ | |
2319 | static int snd_ctl_dev_disconnect(struct snd_device *device) | |
2320 | { | |
2321 | struct snd_card *card = device->device_data; | |
2322 | struct snd_ctl_file *ctl; | |
2323 | ||
2324 | scoped_guard(read_lock_irqsave, &card->ctl_files_rwlock) { | |
2325 | list_for_each_entry(ctl, &card->ctl_files, list) { | |
2326 | wake_up(&ctl->change_sleep); | |
2327 | snd_kill_fasync(ctl->fasync, SIGIO, POLL_ERR); | |
2328 | } | |
2329 | } | |
2330 | ||
2331 | call_snd_ctl_lops(card, ldisconnect); | |
2332 | return snd_unregister_device(card->ctl_dev); | |
2333 | } | |
2334 | ||
2335 | /* | |
2336 | * free all controls | |
2337 | */ | |
2338 | static int snd_ctl_dev_free(struct snd_device *device) | |
2339 | { | |
2340 | struct snd_card *card = device->device_data; | |
2341 | struct snd_kcontrol *control; | |
2342 | ||
2343 | scoped_guard(rwsem_write, &card->controls_rwsem) { | |
2344 | while (!list_empty(&card->controls)) { | |
2345 | control = snd_kcontrol(card->controls.next); | |
2346 | __snd_ctl_remove(card, control, false); | |
2347 | } | |
2348 | ||
2349 | #ifdef CONFIG_SND_CTL_FAST_LOOKUP | |
2350 | xa_destroy(&card->ctl_numids); | |
2351 | xa_destroy(&card->ctl_hash); | |
2352 | #endif | |
2353 | } | |
2354 | put_device(card->ctl_dev); | |
2355 | return 0; | |
2356 | } | |
2357 | ||
2358 | /* | |
2359 | * create control core: | |
2360 | * called from init.c | |
2361 | */ | |
2362 | int snd_ctl_create(struct snd_card *card) | |
2363 | { | |
2364 | static const struct snd_device_ops ops = { | |
2365 | .dev_free = snd_ctl_dev_free, | |
2366 | .dev_register = snd_ctl_dev_register, | |
2367 | .dev_disconnect = snd_ctl_dev_disconnect, | |
2368 | }; | |
2369 | int err; | |
2370 | ||
2371 | if (snd_BUG_ON(!card)) | |
2372 | return -ENXIO; | |
2373 | if (snd_BUG_ON(card->number < 0 || card->number >= SNDRV_CARDS)) | |
2374 | return -ENXIO; | |
2375 | ||
2376 | err = snd_device_alloc(&card->ctl_dev, card); | |
2377 | if (err < 0) | |
2378 | return err; | |
2379 | dev_set_name(card->ctl_dev, "controlC%d", card->number); | |
2380 | ||
2381 | err = snd_device_new(card, SNDRV_DEV_CONTROL, card, &ops); | |
2382 | if (err < 0) | |
2383 | put_device(card->ctl_dev); | |
2384 | return err; | |
2385 | } | |
2386 | ||
2387 | /* | |
2388 | * Frequently used control callbacks/helpers | |
2389 | */ | |
2390 | ||
2391 | /** | |
2392 | * snd_ctl_boolean_mono_info - Helper function for a standard boolean info | |
2393 | * callback with a mono channel | |
2394 | * @kcontrol: the kcontrol instance | |
2395 | * @uinfo: info to store | |
2396 | * | |
2397 | * This is a function that can be used as info callback for a standard | |
2398 | * boolean control with a single mono channel. | |
2399 | * | |
2400 | * Return: Zero (always successful) | |
2401 | */ | |
2402 | int snd_ctl_boolean_mono_info(struct snd_kcontrol *kcontrol, | |
2403 | struct snd_ctl_elem_info *uinfo) | |
2404 | { | |
2405 | uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN; | |
2406 | uinfo->count = 1; | |
2407 | uinfo->value.integer.min = 0; | |
2408 | uinfo->value.integer.max = 1; | |
2409 | return 0; | |
2410 | } | |
2411 | EXPORT_SYMBOL(snd_ctl_boolean_mono_info); | |
2412 | ||
2413 | /** | |
2414 | * snd_ctl_boolean_stereo_info - Helper function for a standard boolean info | |
2415 | * callback with stereo two channels | |
2416 | * @kcontrol: the kcontrol instance | |
2417 | * @uinfo: info to store | |
2418 | * | |
2419 | * This is a function that can be used as info callback for a standard | |
2420 | * boolean control with stereo two channels. | |
2421 | * | |
2422 | * Return: Zero (always successful) | |
2423 | */ | |
2424 | int snd_ctl_boolean_stereo_info(struct snd_kcontrol *kcontrol, | |
2425 | struct snd_ctl_elem_info *uinfo) | |
2426 | { | |
2427 | uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN; | |
2428 | uinfo->count = 2; | |
2429 | uinfo->value.integer.min = 0; | |
2430 | uinfo->value.integer.max = 1; | |
2431 | return 0; | |
2432 | } | |
2433 | EXPORT_SYMBOL(snd_ctl_boolean_stereo_info); | |
2434 | ||
2435 | /** | |
2436 | * snd_ctl_enum_info - fills the info structure for an enumerated control | |
2437 | * @info: the structure to be filled | |
2438 | * @channels: the number of the control's channels; often one | |
2439 | * @items: the number of control values; also the size of @names | |
2440 | * @names: an array containing the names of all control values | |
2441 | * | |
2442 | * Sets all required fields in @info to their appropriate values. | |
2443 | * If the control's accessibility is not the default (readable and writable), | |
2444 | * the caller has to fill @info->access. | |
2445 | * | |
2446 | * Return: Zero (always successful) | |
2447 | */ | |
2448 | int snd_ctl_enum_info(struct snd_ctl_elem_info *info, unsigned int channels, | |
2449 | unsigned int items, const char *const names[]) | |
2450 | { | |
2451 | info->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED; | |
2452 | info->count = channels; | |
2453 | info->value.enumerated.items = items; | |
2454 | if (!items) | |
2455 | return 0; | |
2456 | if (info->value.enumerated.item >= items) | |
2457 | info->value.enumerated.item = items - 1; | |
2458 | WARN(strlen(names[info->value.enumerated.item]) >= sizeof(info->value.enumerated.name), | |
2459 | "ALSA: too long item name '%s'\n", | |
2460 | names[info->value.enumerated.item]); | |
2461 | strscpy(info->value.enumerated.name, | |
2462 | names[info->value.enumerated.item], | |
2463 | sizeof(info->value.enumerated.name)); | |
2464 | return 0; | |
2465 | } | |
2466 | EXPORT_SYMBOL(snd_ctl_enum_info); |