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