xref: /openbmc/linux/sound/core/rawmidi.c (revision 8dde5715)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Abstract layer for MIDI v1.0 stream
4  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5  */
6 
7 #include <sound/core.h>
8 #include <linux/major.h>
9 #include <linux/init.h>
10 #include <linux/sched/signal.h>
11 #include <linux/slab.h>
12 #include <linux/time.h>
13 #include <linux/wait.h>
14 #include <linux/mutex.h>
15 #include <linux/module.h>
16 #include <linux/delay.h>
17 #include <linux/mm.h>
18 #include <linux/nospec.h>
19 #include <sound/rawmidi.h>
20 #include <sound/info.h>
21 #include <sound/control.h>
22 #include <sound/minors.h>
23 #include <sound/initval.h>
24 
25 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>");
26 MODULE_DESCRIPTION("Midlevel RawMidi code for ALSA.");
27 MODULE_LICENSE("GPL");
28 
29 #ifdef CONFIG_SND_OSSEMUL
30 static int midi_map[SNDRV_CARDS];
31 static int amidi_map[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS-1)] = 1};
32 module_param_array(midi_map, int, NULL, 0444);
33 MODULE_PARM_DESC(midi_map, "Raw MIDI device number assigned to 1st OSS device.");
34 module_param_array(amidi_map, int, NULL, 0444);
35 MODULE_PARM_DESC(amidi_map, "Raw MIDI device number assigned to 2nd OSS device.");
36 #endif /* CONFIG_SND_OSSEMUL */
37 
38 static int snd_rawmidi_free(struct snd_rawmidi *rawmidi);
39 static int snd_rawmidi_dev_free(struct snd_device *device);
40 static int snd_rawmidi_dev_register(struct snd_device *device);
41 static int snd_rawmidi_dev_disconnect(struct snd_device *device);
42 
43 static LIST_HEAD(snd_rawmidi_devices);
44 static DEFINE_MUTEX(register_mutex);
45 
46 #define rmidi_err(rmidi, fmt, args...) \
47 	dev_err(&(rmidi)->dev, fmt, ##args)
48 #define rmidi_warn(rmidi, fmt, args...) \
49 	dev_warn(&(rmidi)->dev, fmt, ##args)
50 #define rmidi_dbg(rmidi, fmt, args...) \
51 	dev_dbg(&(rmidi)->dev, fmt, ##args)
52 
53 static struct snd_rawmidi *snd_rawmidi_search(struct snd_card *card, int device)
54 {
55 	struct snd_rawmidi *rawmidi;
56 
57 	list_for_each_entry(rawmidi, &snd_rawmidi_devices, list)
58 		if (rawmidi->card == card && rawmidi->device == device)
59 			return rawmidi;
60 	return NULL;
61 }
62 
63 static inline unsigned short snd_rawmidi_file_flags(struct file *file)
64 {
65 	switch (file->f_mode & (FMODE_READ | FMODE_WRITE)) {
66 	case FMODE_WRITE:
67 		return SNDRV_RAWMIDI_LFLG_OUTPUT;
68 	case FMODE_READ:
69 		return SNDRV_RAWMIDI_LFLG_INPUT;
70 	default:
71 		return SNDRV_RAWMIDI_LFLG_OPEN;
72 	}
73 }
74 
75 static inline int snd_rawmidi_ready(struct snd_rawmidi_substream *substream)
76 {
77 	struct snd_rawmidi_runtime *runtime = substream->runtime;
78 
79 	return runtime->avail >= runtime->avail_min;
80 }
81 
82 static inline int snd_rawmidi_ready_append(struct snd_rawmidi_substream *substream,
83 					   size_t count)
84 {
85 	struct snd_rawmidi_runtime *runtime = substream->runtime;
86 
87 	return runtime->avail >= runtime->avail_min &&
88 	       (!substream->append || runtime->avail >= count);
89 }
90 
91 static void snd_rawmidi_input_event_work(struct work_struct *work)
92 {
93 	struct snd_rawmidi_runtime *runtime =
94 		container_of(work, struct snd_rawmidi_runtime, event_work);
95 
96 	if (runtime->event)
97 		runtime->event(runtime->substream);
98 }
99 
100 static int snd_rawmidi_runtime_create(struct snd_rawmidi_substream *substream)
101 {
102 	struct snd_rawmidi_runtime *runtime;
103 
104 	runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
105 	if (!runtime)
106 		return -ENOMEM;
107 	runtime->substream = substream;
108 	spin_lock_init(&runtime->lock);
109 	init_waitqueue_head(&runtime->sleep);
110 	INIT_WORK(&runtime->event_work, snd_rawmidi_input_event_work);
111 	runtime->event = NULL;
112 	runtime->buffer_size = PAGE_SIZE;
113 	runtime->avail_min = 1;
114 	if (substream->stream == SNDRV_RAWMIDI_STREAM_INPUT)
115 		runtime->avail = 0;
116 	else
117 		runtime->avail = runtime->buffer_size;
118 	runtime->buffer = kvzalloc(runtime->buffer_size, GFP_KERNEL);
119 	if (!runtime->buffer) {
120 		kfree(runtime);
121 		return -ENOMEM;
122 	}
123 	runtime->appl_ptr = runtime->hw_ptr = 0;
124 	substream->runtime = runtime;
125 	return 0;
126 }
127 
128 static int snd_rawmidi_runtime_free(struct snd_rawmidi_substream *substream)
129 {
130 	struct snd_rawmidi_runtime *runtime = substream->runtime;
131 
132 	kvfree(runtime->buffer);
133 	kfree(runtime);
134 	substream->runtime = NULL;
135 	return 0;
136 }
137 
138 static inline void snd_rawmidi_output_trigger(struct snd_rawmidi_substream *substream, int up)
139 {
140 	if (!substream->opened)
141 		return;
142 	substream->ops->trigger(substream, up);
143 }
144 
145 static void snd_rawmidi_input_trigger(struct snd_rawmidi_substream *substream, int up)
146 {
147 	if (!substream->opened)
148 		return;
149 	substream->ops->trigger(substream, up);
150 	if (!up)
151 		cancel_work_sync(&substream->runtime->event_work);
152 }
153 
154 static void __reset_runtime_ptrs(struct snd_rawmidi_runtime *runtime,
155 				 bool is_input)
156 {
157 	runtime->drain = 0;
158 	runtime->appl_ptr = runtime->hw_ptr = 0;
159 	runtime->avail = is_input ? 0 : runtime->buffer_size;
160 }
161 
162 static void reset_runtime_ptrs(struct snd_rawmidi_runtime *runtime,
163 			       bool is_input)
164 {
165 	unsigned long flags;
166 
167 	spin_lock_irqsave(&runtime->lock, flags);
168 	__reset_runtime_ptrs(runtime, is_input);
169 	spin_unlock_irqrestore(&runtime->lock, flags);
170 }
171 
172 int snd_rawmidi_drop_output(struct snd_rawmidi_substream *substream)
173 {
174 	snd_rawmidi_output_trigger(substream, 0);
175 	reset_runtime_ptrs(substream->runtime, false);
176 	return 0;
177 }
178 EXPORT_SYMBOL(snd_rawmidi_drop_output);
179 
180 int snd_rawmidi_drain_output(struct snd_rawmidi_substream *substream)
181 {
182 	int err;
183 	long timeout;
184 	struct snd_rawmidi_runtime *runtime = substream->runtime;
185 
186 	err = 0;
187 	runtime->drain = 1;
188 	timeout = wait_event_interruptible_timeout(runtime->sleep,
189 				(runtime->avail >= runtime->buffer_size),
190 				10*HZ);
191 	if (signal_pending(current))
192 		err = -ERESTARTSYS;
193 	if (runtime->avail < runtime->buffer_size && !timeout) {
194 		rmidi_warn(substream->rmidi,
195 			   "rawmidi drain error (avail = %li, buffer_size = %li)\n",
196 			   (long)runtime->avail, (long)runtime->buffer_size);
197 		err = -EIO;
198 	}
199 	runtime->drain = 0;
200 	if (err != -ERESTARTSYS) {
201 		/* we need wait a while to make sure that Tx FIFOs are empty */
202 		if (substream->ops->drain)
203 			substream->ops->drain(substream);
204 		else
205 			msleep(50);
206 		snd_rawmidi_drop_output(substream);
207 	}
208 	return err;
209 }
210 EXPORT_SYMBOL(snd_rawmidi_drain_output);
211 
212 int snd_rawmidi_drain_input(struct snd_rawmidi_substream *substream)
213 {
214 	snd_rawmidi_input_trigger(substream, 0);
215 	reset_runtime_ptrs(substream->runtime, true);
216 	return 0;
217 }
218 EXPORT_SYMBOL(snd_rawmidi_drain_input);
219 
220 /* look for an available substream for the given stream direction;
221  * if a specific subdevice is given, try to assign it
222  */
223 static int assign_substream(struct snd_rawmidi *rmidi, int subdevice,
224 			    int stream, int mode,
225 			    struct snd_rawmidi_substream **sub_ret)
226 {
227 	struct snd_rawmidi_substream *substream;
228 	struct snd_rawmidi_str *s = &rmidi->streams[stream];
229 	static unsigned int info_flags[2] = {
230 		[SNDRV_RAWMIDI_STREAM_OUTPUT] = SNDRV_RAWMIDI_INFO_OUTPUT,
231 		[SNDRV_RAWMIDI_STREAM_INPUT] = SNDRV_RAWMIDI_INFO_INPUT,
232 	};
233 
234 	if (!(rmidi->info_flags & info_flags[stream]))
235 		return -ENXIO;
236 	if (subdevice >= 0 && subdevice >= s->substream_count)
237 		return -ENODEV;
238 
239 	list_for_each_entry(substream, &s->substreams, list) {
240 		if (substream->opened) {
241 			if (stream == SNDRV_RAWMIDI_STREAM_INPUT ||
242 			    !(mode & SNDRV_RAWMIDI_LFLG_APPEND) ||
243 			    !substream->append)
244 				continue;
245 		}
246 		if (subdevice < 0 || subdevice == substream->number) {
247 			*sub_ret = substream;
248 			return 0;
249 		}
250 	}
251 	return -EAGAIN;
252 }
253 
254 /* open and do ref-counting for the given substream */
255 static int open_substream(struct snd_rawmidi *rmidi,
256 			  struct snd_rawmidi_substream *substream,
257 			  int mode)
258 {
259 	int err;
260 
261 	if (substream->use_count == 0) {
262 		err = snd_rawmidi_runtime_create(substream);
263 		if (err < 0)
264 			return err;
265 		err = substream->ops->open(substream);
266 		if (err < 0) {
267 			snd_rawmidi_runtime_free(substream);
268 			return err;
269 		}
270 		substream->opened = 1;
271 		substream->active_sensing = 0;
272 		if (mode & SNDRV_RAWMIDI_LFLG_APPEND)
273 			substream->append = 1;
274 		substream->pid = get_pid(task_pid(current));
275 		rmidi->streams[substream->stream].substream_opened++;
276 	}
277 	substream->use_count++;
278 	return 0;
279 }
280 
281 static void close_substream(struct snd_rawmidi *rmidi,
282 			    struct snd_rawmidi_substream *substream,
283 			    int cleanup);
284 
285 static int rawmidi_open_priv(struct snd_rawmidi *rmidi, int subdevice, int mode,
286 			     struct snd_rawmidi_file *rfile)
287 {
288 	struct snd_rawmidi_substream *sinput = NULL, *soutput = NULL;
289 	int err;
290 
291 	rfile->input = rfile->output = NULL;
292 	if (mode & SNDRV_RAWMIDI_LFLG_INPUT) {
293 		err = assign_substream(rmidi, subdevice,
294 				       SNDRV_RAWMIDI_STREAM_INPUT,
295 				       mode, &sinput);
296 		if (err < 0)
297 			return err;
298 	}
299 	if (mode & SNDRV_RAWMIDI_LFLG_OUTPUT) {
300 		err = assign_substream(rmidi, subdevice,
301 				       SNDRV_RAWMIDI_STREAM_OUTPUT,
302 				       mode, &soutput);
303 		if (err < 0)
304 			return err;
305 	}
306 
307 	if (sinput) {
308 		err = open_substream(rmidi, sinput, mode);
309 		if (err < 0)
310 			return err;
311 	}
312 	if (soutput) {
313 		err = open_substream(rmidi, soutput, mode);
314 		if (err < 0) {
315 			if (sinput)
316 				close_substream(rmidi, sinput, 0);
317 			return err;
318 		}
319 	}
320 
321 	rfile->rmidi = rmidi;
322 	rfile->input = sinput;
323 	rfile->output = soutput;
324 	return 0;
325 }
326 
327 /* called from sound/core/seq/seq_midi.c */
328 int snd_rawmidi_kernel_open(struct snd_card *card, int device, int subdevice,
329 			    int mode, struct snd_rawmidi_file *rfile)
330 {
331 	struct snd_rawmidi *rmidi;
332 	int err = 0;
333 
334 	if (snd_BUG_ON(!rfile))
335 		return -EINVAL;
336 
337 	mutex_lock(&register_mutex);
338 	rmidi = snd_rawmidi_search(card, device);
339 	if (!rmidi)
340 		err = -ENODEV;
341 	else if (!try_module_get(rmidi->card->module))
342 		err = -ENXIO;
343 	mutex_unlock(&register_mutex);
344 	if (err < 0)
345 		return err;
346 
347 	mutex_lock(&rmidi->open_mutex);
348 	err = rawmidi_open_priv(rmidi, subdevice, mode, rfile);
349 	mutex_unlock(&rmidi->open_mutex);
350 	if (err < 0)
351 		module_put(rmidi->card->module);
352 	return err;
353 }
354 EXPORT_SYMBOL(snd_rawmidi_kernel_open);
355 
356 static int snd_rawmidi_open(struct inode *inode, struct file *file)
357 {
358 	int maj = imajor(inode);
359 	struct snd_card *card;
360 	int subdevice;
361 	unsigned short fflags;
362 	int err;
363 	struct snd_rawmidi *rmidi;
364 	struct snd_rawmidi_file *rawmidi_file = NULL;
365 	wait_queue_entry_t wait;
366 
367 	if ((file->f_flags & O_APPEND) && !(file->f_flags & O_NONBLOCK))
368 		return -EINVAL;		/* invalid combination */
369 
370 	err = stream_open(inode, file);
371 	if (err < 0)
372 		return err;
373 
374 	if (maj == snd_major) {
375 		rmidi = snd_lookup_minor_data(iminor(inode),
376 					      SNDRV_DEVICE_TYPE_RAWMIDI);
377 #ifdef CONFIG_SND_OSSEMUL
378 	} else if (maj == SOUND_MAJOR) {
379 		rmidi = snd_lookup_oss_minor_data(iminor(inode),
380 						  SNDRV_OSS_DEVICE_TYPE_MIDI);
381 #endif
382 	} else
383 		return -ENXIO;
384 
385 	if (rmidi == NULL)
386 		return -ENODEV;
387 
388 	if (!try_module_get(rmidi->card->module)) {
389 		snd_card_unref(rmidi->card);
390 		return -ENXIO;
391 	}
392 
393 	mutex_lock(&rmidi->open_mutex);
394 	card = rmidi->card;
395 	err = snd_card_file_add(card, file);
396 	if (err < 0)
397 		goto __error_card;
398 	fflags = snd_rawmidi_file_flags(file);
399 	if ((file->f_flags & O_APPEND) || maj == SOUND_MAJOR) /* OSS emul? */
400 		fflags |= SNDRV_RAWMIDI_LFLG_APPEND;
401 	rawmidi_file = kmalloc(sizeof(*rawmidi_file), GFP_KERNEL);
402 	if (rawmidi_file == NULL) {
403 		err = -ENOMEM;
404 		goto __error;
405 	}
406 	init_waitqueue_entry(&wait, current);
407 	add_wait_queue(&rmidi->open_wait, &wait);
408 	while (1) {
409 		subdevice = snd_ctl_get_preferred_subdevice(card, SND_CTL_SUBDEV_RAWMIDI);
410 		err = rawmidi_open_priv(rmidi, subdevice, fflags, rawmidi_file);
411 		if (err >= 0)
412 			break;
413 		if (err == -EAGAIN) {
414 			if (file->f_flags & O_NONBLOCK) {
415 				err = -EBUSY;
416 				break;
417 			}
418 		} else
419 			break;
420 		set_current_state(TASK_INTERRUPTIBLE);
421 		mutex_unlock(&rmidi->open_mutex);
422 		schedule();
423 		mutex_lock(&rmidi->open_mutex);
424 		if (rmidi->card->shutdown) {
425 			err = -ENODEV;
426 			break;
427 		}
428 		if (signal_pending(current)) {
429 			err = -ERESTARTSYS;
430 			break;
431 		}
432 	}
433 	remove_wait_queue(&rmidi->open_wait, &wait);
434 	if (err < 0) {
435 		kfree(rawmidi_file);
436 		goto __error;
437 	}
438 #ifdef CONFIG_SND_OSSEMUL
439 	if (rawmidi_file->input && rawmidi_file->input->runtime)
440 		rawmidi_file->input->runtime->oss = (maj == SOUND_MAJOR);
441 	if (rawmidi_file->output && rawmidi_file->output->runtime)
442 		rawmidi_file->output->runtime->oss = (maj == SOUND_MAJOR);
443 #endif
444 	file->private_data = rawmidi_file;
445 	mutex_unlock(&rmidi->open_mutex);
446 	snd_card_unref(rmidi->card);
447 	return 0;
448 
449  __error:
450 	snd_card_file_remove(card, file);
451  __error_card:
452 	mutex_unlock(&rmidi->open_mutex);
453 	module_put(rmidi->card->module);
454 	snd_card_unref(rmidi->card);
455 	return err;
456 }
457 
458 static void close_substream(struct snd_rawmidi *rmidi,
459 			    struct snd_rawmidi_substream *substream,
460 			    int cleanup)
461 {
462 	if (--substream->use_count)
463 		return;
464 
465 	if (cleanup) {
466 		if (substream->stream == SNDRV_RAWMIDI_STREAM_INPUT)
467 			snd_rawmidi_input_trigger(substream, 0);
468 		else {
469 			if (substream->active_sensing) {
470 				unsigned char buf = 0xfe;
471 				/* sending single active sensing message
472 				 * to shut the device up
473 				 */
474 				snd_rawmidi_kernel_write(substream, &buf, 1);
475 			}
476 			if (snd_rawmidi_drain_output(substream) == -ERESTARTSYS)
477 				snd_rawmidi_output_trigger(substream, 0);
478 		}
479 	}
480 	substream->ops->close(substream);
481 	if (substream->runtime->private_free)
482 		substream->runtime->private_free(substream);
483 	snd_rawmidi_runtime_free(substream);
484 	substream->opened = 0;
485 	substream->append = 0;
486 	put_pid(substream->pid);
487 	substream->pid = NULL;
488 	rmidi->streams[substream->stream].substream_opened--;
489 }
490 
491 static void rawmidi_release_priv(struct snd_rawmidi_file *rfile)
492 {
493 	struct snd_rawmidi *rmidi;
494 
495 	rmidi = rfile->rmidi;
496 	mutex_lock(&rmidi->open_mutex);
497 	if (rfile->input) {
498 		close_substream(rmidi, rfile->input, 1);
499 		rfile->input = NULL;
500 	}
501 	if (rfile->output) {
502 		close_substream(rmidi, rfile->output, 1);
503 		rfile->output = NULL;
504 	}
505 	rfile->rmidi = NULL;
506 	mutex_unlock(&rmidi->open_mutex);
507 	wake_up(&rmidi->open_wait);
508 }
509 
510 /* called from sound/core/seq/seq_midi.c */
511 int snd_rawmidi_kernel_release(struct snd_rawmidi_file *rfile)
512 {
513 	struct snd_rawmidi *rmidi;
514 
515 	if (snd_BUG_ON(!rfile))
516 		return -ENXIO;
517 
518 	rmidi = rfile->rmidi;
519 	rawmidi_release_priv(rfile);
520 	module_put(rmidi->card->module);
521 	return 0;
522 }
523 EXPORT_SYMBOL(snd_rawmidi_kernel_release);
524 
525 static int snd_rawmidi_release(struct inode *inode, struct file *file)
526 {
527 	struct snd_rawmidi_file *rfile;
528 	struct snd_rawmidi *rmidi;
529 	struct module *module;
530 
531 	rfile = file->private_data;
532 	rmidi = rfile->rmidi;
533 	rawmidi_release_priv(rfile);
534 	kfree(rfile);
535 	module = rmidi->card->module;
536 	snd_card_file_remove(rmidi->card, file);
537 	module_put(module);
538 	return 0;
539 }
540 
541 static int snd_rawmidi_info(struct snd_rawmidi_substream *substream,
542 			    struct snd_rawmidi_info *info)
543 {
544 	struct snd_rawmidi *rmidi;
545 
546 	if (substream == NULL)
547 		return -ENODEV;
548 	rmidi = substream->rmidi;
549 	memset(info, 0, sizeof(*info));
550 	info->card = rmidi->card->number;
551 	info->device = rmidi->device;
552 	info->subdevice = substream->number;
553 	info->stream = substream->stream;
554 	info->flags = rmidi->info_flags;
555 	strcpy(info->id, rmidi->id);
556 	strcpy(info->name, rmidi->name);
557 	strcpy(info->subname, substream->name);
558 	info->subdevices_count = substream->pstr->substream_count;
559 	info->subdevices_avail = (substream->pstr->substream_count -
560 				  substream->pstr->substream_opened);
561 	return 0;
562 }
563 
564 static int snd_rawmidi_info_user(struct snd_rawmidi_substream *substream,
565 				 struct snd_rawmidi_info __user *_info)
566 {
567 	struct snd_rawmidi_info info;
568 	int err;
569 
570 	err = snd_rawmidi_info(substream, &info);
571 	if (err < 0)
572 		return err;
573 	if (copy_to_user(_info, &info, sizeof(struct snd_rawmidi_info)))
574 		return -EFAULT;
575 	return 0;
576 }
577 
578 static int __snd_rawmidi_info_select(struct snd_card *card,
579 				     struct snd_rawmidi_info *info)
580 {
581 	struct snd_rawmidi *rmidi;
582 	struct snd_rawmidi_str *pstr;
583 	struct snd_rawmidi_substream *substream;
584 
585 	rmidi = snd_rawmidi_search(card, info->device);
586 	if (!rmidi)
587 		return -ENXIO;
588 	if (info->stream < 0 || info->stream > 1)
589 		return -EINVAL;
590 	info->stream = array_index_nospec(info->stream, 2);
591 	pstr = &rmidi->streams[info->stream];
592 	if (pstr->substream_count == 0)
593 		return -ENOENT;
594 	if (info->subdevice >= pstr->substream_count)
595 		return -ENXIO;
596 	list_for_each_entry(substream, &pstr->substreams, list) {
597 		if ((unsigned int)substream->number == info->subdevice)
598 			return snd_rawmidi_info(substream, info);
599 	}
600 	return -ENXIO;
601 }
602 
603 int snd_rawmidi_info_select(struct snd_card *card, struct snd_rawmidi_info *info)
604 {
605 	int ret;
606 
607 	mutex_lock(&register_mutex);
608 	ret = __snd_rawmidi_info_select(card, info);
609 	mutex_unlock(&register_mutex);
610 	return ret;
611 }
612 EXPORT_SYMBOL(snd_rawmidi_info_select);
613 
614 static int snd_rawmidi_info_select_user(struct snd_card *card,
615 					struct snd_rawmidi_info __user *_info)
616 {
617 	int err;
618 	struct snd_rawmidi_info info;
619 
620 	if (get_user(info.device, &_info->device))
621 		return -EFAULT;
622 	if (get_user(info.stream, &_info->stream))
623 		return -EFAULT;
624 	if (get_user(info.subdevice, &_info->subdevice))
625 		return -EFAULT;
626 	err = snd_rawmidi_info_select(card, &info);
627 	if (err < 0)
628 		return err;
629 	if (copy_to_user(_info, &info, sizeof(struct snd_rawmidi_info)))
630 		return -EFAULT;
631 	return 0;
632 }
633 
634 static int resize_runtime_buffer(struct snd_rawmidi_runtime *runtime,
635 				 struct snd_rawmidi_params *params,
636 				 bool is_input)
637 {
638 	char *newbuf, *oldbuf;
639 
640 	if (params->buffer_size < 32 || params->buffer_size > 1024L * 1024L)
641 		return -EINVAL;
642 	if (params->avail_min < 1 || params->avail_min > params->buffer_size)
643 		return -EINVAL;
644 	if (params->buffer_size != runtime->buffer_size) {
645 		newbuf = kvzalloc(params->buffer_size, GFP_KERNEL);
646 		if (!newbuf)
647 			return -ENOMEM;
648 		spin_lock_irq(&runtime->lock);
649 		oldbuf = runtime->buffer;
650 		runtime->buffer = newbuf;
651 		runtime->buffer_size = params->buffer_size;
652 		__reset_runtime_ptrs(runtime, is_input);
653 		spin_unlock_irq(&runtime->lock);
654 		kvfree(oldbuf);
655 	}
656 	runtime->avail_min = params->avail_min;
657 	return 0;
658 }
659 
660 int snd_rawmidi_output_params(struct snd_rawmidi_substream *substream,
661 			      struct snd_rawmidi_params *params)
662 {
663 	if (substream->append && substream->use_count > 1)
664 		return -EBUSY;
665 	snd_rawmidi_drain_output(substream);
666 	substream->active_sensing = !params->no_active_sensing;
667 	return resize_runtime_buffer(substream->runtime, params, false);
668 }
669 EXPORT_SYMBOL(snd_rawmidi_output_params);
670 
671 int snd_rawmidi_input_params(struct snd_rawmidi_substream *substream,
672 			     struct snd_rawmidi_params *params)
673 {
674 	snd_rawmidi_drain_input(substream);
675 	return resize_runtime_buffer(substream->runtime, params, true);
676 }
677 EXPORT_SYMBOL(snd_rawmidi_input_params);
678 
679 static int snd_rawmidi_output_status(struct snd_rawmidi_substream *substream,
680 				     struct snd_rawmidi_status *status)
681 {
682 	struct snd_rawmidi_runtime *runtime = substream->runtime;
683 
684 	memset(status, 0, sizeof(*status));
685 	status->stream = SNDRV_RAWMIDI_STREAM_OUTPUT;
686 	spin_lock_irq(&runtime->lock);
687 	status->avail = runtime->avail;
688 	spin_unlock_irq(&runtime->lock);
689 	return 0;
690 }
691 
692 static int snd_rawmidi_input_status(struct snd_rawmidi_substream *substream,
693 				    struct snd_rawmidi_status *status)
694 {
695 	struct snd_rawmidi_runtime *runtime = substream->runtime;
696 
697 	memset(status, 0, sizeof(*status));
698 	status->stream = SNDRV_RAWMIDI_STREAM_INPUT;
699 	spin_lock_irq(&runtime->lock);
700 	status->avail = runtime->avail;
701 	status->xruns = runtime->xruns;
702 	runtime->xruns = 0;
703 	spin_unlock_irq(&runtime->lock);
704 	return 0;
705 }
706 
707 static long snd_rawmidi_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
708 {
709 	struct snd_rawmidi_file *rfile;
710 	void __user *argp = (void __user *)arg;
711 
712 	rfile = file->private_data;
713 	if (((cmd >> 8) & 0xff) != 'W')
714 		return -ENOTTY;
715 	switch (cmd) {
716 	case SNDRV_RAWMIDI_IOCTL_PVERSION:
717 		return put_user(SNDRV_RAWMIDI_VERSION, (int __user *)argp) ? -EFAULT : 0;
718 	case SNDRV_RAWMIDI_IOCTL_INFO:
719 	{
720 		int stream;
721 		struct snd_rawmidi_info __user *info = argp;
722 
723 		if (get_user(stream, &info->stream))
724 			return -EFAULT;
725 		switch (stream) {
726 		case SNDRV_RAWMIDI_STREAM_INPUT:
727 			return snd_rawmidi_info_user(rfile->input, info);
728 		case SNDRV_RAWMIDI_STREAM_OUTPUT:
729 			return snd_rawmidi_info_user(rfile->output, info);
730 		default:
731 			return -EINVAL;
732 		}
733 	}
734 	case SNDRV_RAWMIDI_IOCTL_PARAMS:
735 	{
736 		struct snd_rawmidi_params params;
737 
738 		if (copy_from_user(&params, argp, sizeof(struct snd_rawmidi_params)))
739 			return -EFAULT;
740 		switch (params.stream) {
741 		case SNDRV_RAWMIDI_STREAM_OUTPUT:
742 			if (rfile->output == NULL)
743 				return -EINVAL;
744 			return snd_rawmidi_output_params(rfile->output, &params);
745 		case SNDRV_RAWMIDI_STREAM_INPUT:
746 			if (rfile->input == NULL)
747 				return -EINVAL;
748 			return snd_rawmidi_input_params(rfile->input, &params);
749 		default:
750 			return -EINVAL;
751 		}
752 	}
753 	case SNDRV_RAWMIDI_IOCTL_STATUS:
754 	{
755 		int err = 0;
756 		struct snd_rawmidi_status status;
757 
758 		if (copy_from_user(&status, argp, sizeof(struct snd_rawmidi_status)))
759 			return -EFAULT;
760 		switch (status.stream) {
761 		case SNDRV_RAWMIDI_STREAM_OUTPUT:
762 			if (rfile->output == NULL)
763 				return -EINVAL;
764 			err = snd_rawmidi_output_status(rfile->output, &status);
765 			break;
766 		case SNDRV_RAWMIDI_STREAM_INPUT:
767 			if (rfile->input == NULL)
768 				return -EINVAL;
769 			err = snd_rawmidi_input_status(rfile->input, &status);
770 			break;
771 		default:
772 			return -EINVAL;
773 		}
774 		if (err < 0)
775 			return err;
776 		if (copy_to_user(argp, &status, sizeof(struct snd_rawmidi_status)))
777 			return -EFAULT;
778 		return 0;
779 	}
780 	case SNDRV_RAWMIDI_IOCTL_DROP:
781 	{
782 		int val;
783 
784 		if (get_user(val, (int __user *) argp))
785 			return -EFAULT;
786 		switch (val) {
787 		case SNDRV_RAWMIDI_STREAM_OUTPUT:
788 			if (rfile->output == NULL)
789 				return -EINVAL;
790 			return snd_rawmidi_drop_output(rfile->output);
791 		default:
792 			return -EINVAL;
793 		}
794 	}
795 	case SNDRV_RAWMIDI_IOCTL_DRAIN:
796 	{
797 		int val;
798 
799 		if (get_user(val, (int __user *) argp))
800 			return -EFAULT;
801 		switch (val) {
802 		case SNDRV_RAWMIDI_STREAM_OUTPUT:
803 			if (rfile->output == NULL)
804 				return -EINVAL;
805 			return snd_rawmidi_drain_output(rfile->output);
806 		case SNDRV_RAWMIDI_STREAM_INPUT:
807 			if (rfile->input == NULL)
808 				return -EINVAL;
809 			return snd_rawmidi_drain_input(rfile->input);
810 		default:
811 			return -EINVAL;
812 		}
813 	}
814 	default:
815 		rmidi_dbg(rfile->rmidi,
816 			  "rawmidi: unknown command = 0x%x\n", cmd);
817 	}
818 	return -ENOTTY;
819 }
820 
821 static int snd_rawmidi_control_ioctl(struct snd_card *card,
822 				     struct snd_ctl_file *control,
823 				     unsigned int cmd,
824 				     unsigned long arg)
825 {
826 	void __user *argp = (void __user *)arg;
827 
828 	switch (cmd) {
829 	case SNDRV_CTL_IOCTL_RAWMIDI_NEXT_DEVICE:
830 	{
831 		int device;
832 
833 		if (get_user(device, (int __user *)argp))
834 			return -EFAULT;
835 		if (device >= SNDRV_RAWMIDI_DEVICES) /* next device is -1 */
836 			device = SNDRV_RAWMIDI_DEVICES - 1;
837 		mutex_lock(&register_mutex);
838 		device = device < 0 ? 0 : device + 1;
839 		while (device < SNDRV_RAWMIDI_DEVICES) {
840 			if (snd_rawmidi_search(card, device))
841 				break;
842 			device++;
843 		}
844 		if (device == SNDRV_RAWMIDI_DEVICES)
845 			device = -1;
846 		mutex_unlock(&register_mutex);
847 		if (put_user(device, (int __user *)argp))
848 			return -EFAULT;
849 		return 0;
850 	}
851 	case SNDRV_CTL_IOCTL_RAWMIDI_PREFER_SUBDEVICE:
852 	{
853 		int val;
854 
855 		if (get_user(val, (int __user *)argp))
856 			return -EFAULT;
857 		control->preferred_subdevice[SND_CTL_SUBDEV_RAWMIDI] = val;
858 		return 0;
859 	}
860 	case SNDRV_CTL_IOCTL_RAWMIDI_INFO:
861 		return snd_rawmidi_info_select_user(card, argp);
862 	}
863 	return -ENOIOCTLCMD;
864 }
865 
866 /**
867  * snd_rawmidi_receive - receive the input data from the device
868  * @substream: the rawmidi substream
869  * @buffer: the buffer pointer
870  * @count: the data size to read
871  *
872  * Reads the data from the internal buffer.
873  *
874  * Return: The size of read data, or a negative error code on failure.
875  */
876 int snd_rawmidi_receive(struct snd_rawmidi_substream *substream,
877 			const unsigned char *buffer, int count)
878 {
879 	unsigned long flags;
880 	int result = 0, count1;
881 	struct snd_rawmidi_runtime *runtime = substream->runtime;
882 
883 	if (!substream->opened)
884 		return -EBADFD;
885 	if (runtime->buffer == NULL) {
886 		rmidi_dbg(substream->rmidi,
887 			  "snd_rawmidi_receive: input is not active!!!\n");
888 		return -EINVAL;
889 	}
890 	spin_lock_irqsave(&runtime->lock, flags);
891 	if (count == 1) {	/* special case, faster code */
892 		substream->bytes++;
893 		if (runtime->avail < runtime->buffer_size) {
894 			runtime->buffer[runtime->hw_ptr++] = buffer[0];
895 			runtime->hw_ptr %= runtime->buffer_size;
896 			runtime->avail++;
897 			result++;
898 		} else {
899 			runtime->xruns++;
900 		}
901 	} else {
902 		substream->bytes += count;
903 		count1 = runtime->buffer_size - runtime->hw_ptr;
904 		if (count1 > count)
905 			count1 = count;
906 		if (count1 > (int)(runtime->buffer_size - runtime->avail))
907 			count1 = runtime->buffer_size - runtime->avail;
908 		memcpy(runtime->buffer + runtime->hw_ptr, buffer, count1);
909 		runtime->hw_ptr += count1;
910 		runtime->hw_ptr %= runtime->buffer_size;
911 		runtime->avail += count1;
912 		count -= count1;
913 		result += count1;
914 		if (count > 0) {
915 			buffer += count1;
916 			count1 = count;
917 			if (count1 > (int)(runtime->buffer_size - runtime->avail)) {
918 				count1 = runtime->buffer_size - runtime->avail;
919 				runtime->xruns += count - count1;
920 			}
921 			if (count1 > 0) {
922 				memcpy(runtime->buffer, buffer, count1);
923 				runtime->hw_ptr = count1;
924 				runtime->avail += count1;
925 				result += count1;
926 			}
927 		}
928 	}
929 	if (result > 0) {
930 		if (runtime->event)
931 			schedule_work(&runtime->event_work);
932 		else if (snd_rawmidi_ready(substream))
933 			wake_up(&runtime->sleep);
934 	}
935 	spin_unlock_irqrestore(&runtime->lock, flags);
936 	return result;
937 }
938 EXPORT_SYMBOL(snd_rawmidi_receive);
939 
940 static long snd_rawmidi_kernel_read1(struct snd_rawmidi_substream *substream,
941 				     unsigned char __user *userbuf,
942 				     unsigned char *kernelbuf, long count)
943 {
944 	unsigned long flags;
945 	long result = 0, count1;
946 	struct snd_rawmidi_runtime *runtime = substream->runtime;
947 	unsigned long appl_ptr;
948 
949 	spin_lock_irqsave(&runtime->lock, flags);
950 	while (count > 0 && runtime->avail) {
951 		count1 = runtime->buffer_size - runtime->appl_ptr;
952 		if (count1 > count)
953 			count1 = count;
954 		if (count1 > (int)runtime->avail)
955 			count1 = runtime->avail;
956 
957 		/* update runtime->appl_ptr before unlocking for userbuf */
958 		appl_ptr = runtime->appl_ptr;
959 		runtime->appl_ptr += count1;
960 		runtime->appl_ptr %= runtime->buffer_size;
961 		runtime->avail -= count1;
962 
963 		if (kernelbuf)
964 			memcpy(kernelbuf + result, runtime->buffer + appl_ptr, count1);
965 		if (userbuf) {
966 			spin_unlock_irqrestore(&runtime->lock, flags);
967 			if (copy_to_user(userbuf + result,
968 					 runtime->buffer + appl_ptr, count1)) {
969 				return result > 0 ? result : -EFAULT;
970 			}
971 			spin_lock_irqsave(&runtime->lock, flags);
972 		}
973 		result += count1;
974 		count -= count1;
975 	}
976 	spin_unlock_irqrestore(&runtime->lock, flags);
977 	return result;
978 }
979 
980 long snd_rawmidi_kernel_read(struct snd_rawmidi_substream *substream,
981 			     unsigned char *buf, long count)
982 {
983 	snd_rawmidi_input_trigger(substream, 1);
984 	return snd_rawmidi_kernel_read1(substream, NULL/*userbuf*/, buf, count);
985 }
986 EXPORT_SYMBOL(snd_rawmidi_kernel_read);
987 
988 static ssize_t snd_rawmidi_read(struct file *file, char __user *buf, size_t count,
989 				loff_t *offset)
990 {
991 	long result;
992 	int count1;
993 	struct snd_rawmidi_file *rfile;
994 	struct snd_rawmidi_substream *substream;
995 	struct snd_rawmidi_runtime *runtime;
996 
997 	rfile = file->private_data;
998 	substream = rfile->input;
999 	if (substream == NULL)
1000 		return -EIO;
1001 	runtime = substream->runtime;
1002 	snd_rawmidi_input_trigger(substream, 1);
1003 	result = 0;
1004 	while (count > 0) {
1005 		spin_lock_irq(&runtime->lock);
1006 		while (!snd_rawmidi_ready(substream)) {
1007 			wait_queue_entry_t wait;
1008 
1009 			if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1010 				spin_unlock_irq(&runtime->lock);
1011 				return result > 0 ? result : -EAGAIN;
1012 			}
1013 			init_waitqueue_entry(&wait, current);
1014 			add_wait_queue(&runtime->sleep, &wait);
1015 			set_current_state(TASK_INTERRUPTIBLE);
1016 			spin_unlock_irq(&runtime->lock);
1017 			schedule();
1018 			remove_wait_queue(&runtime->sleep, &wait);
1019 			if (rfile->rmidi->card->shutdown)
1020 				return -ENODEV;
1021 			if (signal_pending(current))
1022 				return result > 0 ? result : -ERESTARTSYS;
1023 			if (!runtime->avail)
1024 				return result > 0 ? result : -EIO;
1025 			spin_lock_irq(&runtime->lock);
1026 		}
1027 		spin_unlock_irq(&runtime->lock);
1028 		count1 = snd_rawmidi_kernel_read1(substream,
1029 						  (unsigned char __user *)buf,
1030 						  NULL/*kernelbuf*/,
1031 						  count);
1032 		if (count1 < 0)
1033 			return result > 0 ? result : count1;
1034 		result += count1;
1035 		buf += count1;
1036 		count -= count1;
1037 	}
1038 	return result;
1039 }
1040 
1041 /**
1042  * snd_rawmidi_transmit_empty - check whether the output buffer is empty
1043  * @substream: the rawmidi substream
1044  *
1045  * Return: 1 if the internal output buffer is empty, 0 if not.
1046  */
1047 int snd_rawmidi_transmit_empty(struct snd_rawmidi_substream *substream)
1048 {
1049 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1050 	int result;
1051 	unsigned long flags;
1052 
1053 	if (runtime->buffer == NULL) {
1054 		rmidi_dbg(substream->rmidi,
1055 			  "snd_rawmidi_transmit_empty: output is not active!!!\n");
1056 		return 1;
1057 	}
1058 	spin_lock_irqsave(&runtime->lock, flags);
1059 	result = runtime->avail >= runtime->buffer_size;
1060 	spin_unlock_irqrestore(&runtime->lock, flags);
1061 	return result;
1062 }
1063 EXPORT_SYMBOL(snd_rawmidi_transmit_empty);
1064 
1065 /**
1066  * __snd_rawmidi_transmit_peek - copy data from the internal buffer
1067  * @substream: the rawmidi substream
1068  * @buffer: the buffer pointer
1069  * @count: data size to transfer
1070  *
1071  * This is a variant of snd_rawmidi_transmit_peek() without spinlock.
1072  */
1073 int __snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
1074 			      unsigned char *buffer, int count)
1075 {
1076 	int result, count1;
1077 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1078 
1079 	if (runtime->buffer == NULL) {
1080 		rmidi_dbg(substream->rmidi,
1081 			  "snd_rawmidi_transmit_peek: output is not active!!!\n");
1082 		return -EINVAL;
1083 	}
1084 	result = 0;
1085 	if (runtime->avail >= runtime->buffer_size) {
1086 		/* warning: lowlevel layer MUST trigger down the hardware */
1087 		goto __skip;
1088 	}
1089 	if (count == 1) {	/* special case, faster code */
1090 		*buffer = runtime->buffer[runtime->hw_ptr];
1091 		result++;
1092 	} else {
1093 		count1 = runtime->buffer_size - runtime->hw_ptr;
1094 		if (count1 > count)
1095 			count1 = count;
1096 		if (count1 > (int)(runtime->buffer_size - runtime->avail))
1097 			count1 = runtime->buffer_size - runtime->avail;
1098 		memcpy(buffer, runtime->buffer + runtime->hw_ptr, count1);
1099 		count -= count1;
1100 		result += count1;
1101 		if (count > 0) {
1102 			if (count > (int)(runtime->buffer_size - runtime->avail - count1))
1103 				count = runtime->buffer_size - runtime->avail - count1;
1104 			memcpy(buffer + count1, runtime->buffer, count);
1105 			result += count;
1106 		}
1107 	}
1108       __skip:
1109 	return result;
1110 }
1111 EXPORT_SYMBOL(__snd_rawmidi_transmit_peek);
1112 
1113 /**
1114  * snd_rawmidi_transmit_peek - copy data from the internal buffer
1115  * @substream: the rawmidi substream
1116  * @buffer: the buffer pointer
1117  * @count: data size to transfer
1118  *
1119  * Copies data from the internal output buffer to the given buffer.
1120  *
1121  * Call this in the interrupt handler when the midi output is ready,
1122  * and call snd_rawmidi_transmit_ack() after the transmission is
1123  * finished.
1124  *
1125  * Return: The size of copied data, or a negative error code on failure.
1126  */
1127 int snd_rawmidi_transmit_peek(struct snd_rawmidi_substream *substream,
1128 			      unsigned char *buffer, int count)
1129 {
1130 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1131 	int result;
1132 	unsigned long flags;
1133 
1134 	spin_lock_irqsave(&runtime->lock, flags);
1135 	result = __snd_rawmidi_transmit_peek(substream, buffer, count);
1136 	spin_unlock_irqrestore(&runtime->lock, flags);
1137 	return result;
1138 }
1139 EXPORT_SYMBOL(snd_rawmidi_transmit_peek);
1140 
1141 /**
1142  * __snd_rawmidi_transmit_ack - acknowledge the transmission
1143  * @substream: the rawmidi substream
1144  * @count: the transferred count
1145  *
1146  * This is a variant of __snd_rawmidi_transmit_ack() without spinlock.
1147  */
1148 int __snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count)
1149 {
1150 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1151 
1152 	if (runtime->buffer == NULL) {
1153 		rmidi_dbg(substream->rmidi,
1154 			  "snd_rawmidi_transmit_ack: output is not active!!!\n");
1155 		return -EINVAL;
1156 	}
1157 	snd_BUG_ON(runtime->avail + count > runtime->buffer_size);
1158 	runtime->hw_ptr += count;
1159 	runtime->hw_ptr %= runtime->buffer_size;
1160 	runtime->avail += count;
1161 	substream->bytes += count;
1162 	if (count > 0) {
1163 		if (runtime->drain || snd_rawmidi_ready(substream))
1164 			wake_up(&runtime->sleep);
1165 	}
1166 	return count;
1167 }
1168 EXPORT_SYMBOL(__snd_rawmidi_transmit_ack);
1169 
1170 /**
1171  * snd_rawmidi_transmit_ack - acknowledge the transmission
1172  * @substream: the rawmidi substream
1173  * @count: the transferred count
1174  *
1175  * Advances the hardware pointer for the internal output buffer with
1176  * the given size and updates the condition.
1177  * Call after the transmission is finished.
1178  *
1179  * Return: The advanced size if successful, or a negative error code on failure.
1180  */
1181 int snd_rawmidi_transmit_ack(struct snd_rawmidi_substream *substream, int count)
1182 {
1183 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1184 	int result;
1185 	unsigned long flags;
1186 
1187 	spin_lock_irqsave(&runtime->lock, flags);
1188 	result = __snd_rawmidi_transmit_ack(substream, count);
1189 	spin_unlock_irqrestore(&runtime->lock, flags);
1190 	return result;
1191 }
1192 EXPORT_SYMBOL(snd_rawmidi_transmit_ack);
1193 
1194 /**
1195  * snd_rawmidi_transmit - copy from the buffer to the device
1196  * @substream: the rawmidi substream
1197  * @buffer: the buffer pointer
1198  * @count: the data size to transfer
1199  *
1200  * Copies data from the buffer to the device and advances the pointer.
1201  *
1202  * Return: The copied size if successful, or a negative error code on failure.
1203  */
1204 int snd_rawmidi_transmit(struct snd_rawmidi_substream *substream,
1205 			 unsigned char *buffer, int count)
1206 {
1207 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1208 	int result;
1209 	unsigned long flags;
1210 
1211 	spin_lock_irqsave(&runtime->lock, flags);
1212 	if (!substream->opened)
1213 		result = -EBADFD;
1214 	else {
1215 		count = __snd_rawmidi_transmit_peek(substream, buffer, count);
1216 		if (count <= 0)
1217 			result = count;
1218 		else
1219 			result = __snd_rawmidi_transmit_ack(substream, count);
1220 	}
1221 	spin_unlock_irqrestore(&runtime->lock, flags);
1222 	return result;
1223 }
1224 EXPORT_SYMBOL(snd_rawmidi_transmit);
1225 
1226 /**
1227  * snd_rawmidi_proceed - Discard the all pending bytes and proceed
1228  * @substream: rawmidi substream
1229  *
1230  * Return: the number of discarded bytes
1231  */
1232 int snd_rawmidi_proceed(struct snd_rawmidi_substream *substream)
1233 {
1234 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1235 	unsigned long flags;
1236 	int count = 0;
1237 
1238 	spin_lock_irqsave(&runtime->lock, flags);
1239 	if (runtime->avail < runtime->buffer_size) {
1240 		count = runtime->buffer_size - runtime->avail;
1241 		__snd_rawmidi_transmit_ack(substream, count);
1242 	}
1243 	spin_unlock_irqrestore(&runtime->lock, flags);
1244 	return count;
1245 }
1246 EXPORT_SYMBOL(snd_rawmidi_proceed);
1247 
1248 static long snd_rawmidi_kernel_write1(struct snd_rawmidi_substream *substream,
1249 				      const unsigned char __user *userbuf,
1250 				      const unsigned char *kernelbuf,
1251 				      long count)
1252 {
1253 	unsigned long flags;
1254 	long count1, result;
1255 	struct snd_rawmidi_runtime *runtime = substream->runtime;
1256 	unsigned long appl_ptr;
1257 
1258 	if (!kernelbuf && !userbuf)
1259 		return -EINVAL;
1260 	if (snd_BUG_ON(!runtime->buffer))
1261 		return -EINVAL;
1262 
1263 	result = 0;
1264 	spin_lock_irqsave(&runtime->lock, flags);
1265 	if (substream->append) {
1266 		if ((long)runtime->avail < count) {
1267 			spin_unlock_irqrestore(&runtime->lock, flags);
1268 			return -EAGAIN;
1269 		}
1270 	}
1271 	while (count > 0 && runtime->avail > 0) {
1272 		count1 = runtime->buffer_size - runtime->appl_ptr;
1273 		if (count1 > count)
1274 			count1 = count;
1275 		if (count1 > (long)runtime->avail)
1276 			count1 = runtime->avail;
1277 
1278 		/* update runtime->appl_ptr before unlocking for userbuf */
1279 		appl_ptr = runtime->appl_ptr;
1280 		runtime->appl_ptr += count1;
1281 		runtime->appl_ptr %= runtime->buffer_size;
1282 		runtime->avail -= count1;
1283 
1284 		if (kernelbuf)
1285 			memcpy(runtime->buffer + appl_ptr,
1286 			       kernelbuf + result, count1);
1287 		else if (userbuf) {
1288 			spin_unlock_irqrestore(&runtime->lock, flags);
1289 			if (copy_from_user(runtime->buffer + appl_ptr,
1290 					   userbuf + result, count1)) {
1291 				spin_lock_irqsave(&runtime->lock, flags);
1292 				result = result > 0 ? result : -EFAULT;
1293 				goto __end;
1294 			}
1295 			spin_lock_irqsave(&runtime->lock, flags);
1296 		}
1297 		result += count1;
1298 		count -= count1;
1299 	}
1300       __end:
1301 	count1 = runtime->avail < runtime->buffer_size;
1302 	spin_unlock_irqrestore(&runtime->lock, flags);
1303 	if (count1)
1304 		snd_rawmidi_output_trigger(substream, 1);
1305 	return result;
1306 }
1307 
1308 long snd_rawmidi_kernel_write(struct snd_rawmidi_substream *substream,
1309 			      const unsigned char *buf, long count)
1310 {
1311 	return snd_rawmidi_kernel_write1(substream, NULL, buf, count);
1312 }
1313 EXPORT_SYMBOL(snd_rawmidi_kernel_write);
1314 
1315 static ssize_t snd_rawmidi_write(struct file *file, const char __user *buf,
1316 				 size_t count, loff_t *offset)
1317 {
1318 	long result, timeout;
1319 	int count1;
1320 	struct snd_rawmidi_file *rfile;
1321 	struct snd_rawmidi_runtime *runtime;
1322 	struct snd_rawmidi_substream *substream;
1323 
1324 	rfile = file->private_data;
1325 	substream = rfile->output;
1326 	runtime = substream->runtime;
1327 	/* we cannot put an atomic message to our buffer */
1328 	if (substream->append && count > runtime->buffer_size)
1329 		return -EIO;
1330 	result = 0;
1331 	while (count > 0) {
1332 		spin_lock_irq(&runtime->lock);
1333 		while (!snd_rawmidi_ready_append(substream, count)) {
1334 			wait_queue_entry_t wait;
1335 
1336 			if (file->f_flags & O_NONBLOCK) {
1337 				spin_unlock_irq(&runtime->lock);
1338 				return result > 0 ? result : -EAGAIN;
1339 			}
1340 			init_waitqueue_entry(&wait, current);
1341 			add_wait_queue(&runtime->sleep, &wait);
1342 			set_current_state(TASK_INTERRUPTIBLE);
1343 			spin_unlock_irq(&runtime->lock);
1344 			timeout = schedule_timeout(30 * HZ);
1345 			remove_wait_queue(&runtime->sleep, &wait);
1346 			if (rfile->rmidi->card->shutdown)
1347 				return -ENODEV;
1348 			if (signal_pending(current))
1349 				return result > 0 ? result : -ERESTARTSYS;
1350 			if (!runtime->avail && !timeout)
1351 				return result > 0 ? result : -EIO;
1352 			spin_lock_irq(&runtime->lock);
1353 		}
1354 		spin_unlock_irq(&runtime->lock);
1355 		count1 = snd_rawmidi_kernel_write1(substream, buf, NULL, count);
1356 		if (count1 < 0)
1357 			return result > 0 ? result : count1;
1358 		result += count1;
1359 		buf += count1;
1360 		if ((size_t)count1 < count && (file->f_flags & O_NONBLOCK))
1361 			break;
1362 		count -= count1;
1363 	}
1364 	if (file->f_flags & O_DSYNC) {
1365 		spin_lock_irq(&runtime->lock);
1366 		while (runtime->avail != runtime->buffer_size) {
1367 			wait_queue_entry_t wait;
1368 			unsigned int last_avail = runtime->avail;
1369 
1370 			init_waitqueue_entry(&wait, current);
1371 			add_wait_queue(&runtime->sleep, &wait);
1372 			set_current_state(TASK_INTERRUPTIBLE);
1373 			spin_unlock_irq(&runtime->lock);
1374 			timeout = schedule_timeout(30 * HZ);
1375 			remove_wait_queue(&runtime->sleep, &wait);
1376 			if (signal_pending(current))
1377 				return result > 0 ? result : -ERESTARTSYS;
1378 			if (runtime->avail == last_avail && !timeout)
1379 				return result > 0 ? result : -EIO;
1380 			spin_lock_irq(&runtime->lock);
1381 		}
1382 		spin_unlock_irq(&runtime->lock);
1383 	}
1384 	return result;
1385 }
1386 
1387 static __poll_t snd_rawmidi_poll(struct file *file, poll_table *wait)
1388 {
1389 	struct snd_rawmidi_file *rfile;
1390 	struct snd_rawmidi_runtime *runtime;
1391 	__poll_t mask;
1392 
1393 	rfile = file->private_data;
1394 	if (rfile->input != NULL) {
1395 		runtime = rfile->input->runtime;
1396 		snd_rawmidi_input_trigger(rfile->input, 1);
1397 		poll_wait(file, &runtime->sleep, wait);
1398 	}
1399 	if (rfile->output != NULL) {
1400 		runtime = rfile->output->runtime;
1401 		poll_wait(file, &runtime->sleep, wait);
1402 	}
1403 	mask = 0;
1404 	if (rfile->input != NULL) {
1405 		if (snd_rawmidi_ready(rfile->input))
1406 			mask |= EPOLLIN | EPOLLRDNORM;
1407 	}
1408 	if (rfile->output != NULL) {
1409 		if (snd_rawmidi_ready(rfile->output))
1410 			mask |= EPOLLOUT | EPOLLWRNORM;
1411 	}
1412 	return mask;
1413 }
1414 
1415 /*
1416  */
1417 #ifdef CONFIG_COMPAT
1418 #include "rawmidi_compat.c"
1419 #else
1420 #define snd_rawmidi_ioctl_compat	NULL
1421 #endif
1422 
1423 /*
1424  */
1425 
1426 static void snd_rawmidi_proc_info_read(struct snd_info_entry *entry,
1427 				       struct snd_info_buffer *buffer)
1428 {
1429 	struct snd_rawmidi *rmidi;
1430 	struct snd_rawmidi_substream *substream;
1431 	struct snd_rawmidi_runtime *runtime;
1432 
1433 	rmidi = entry->private_data;
1434 	snd_iprintf(buffer, "%s\n\n", rmidi->name);
1435 	mutex_lock(&rmidi->open_mutex);
1436 	if (rmidi->info_flags & SNDRV_RAWMIDI_INFO_OUTPUT) {
1437 		list_for_each_entry(substream,
1438 				    &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams,
1439 				    list) {
1440 			snd_iprintf(buffer,
1441 				    "Output %d\n"
1442 				    "  Tx bytes     : %lu\n",
1443 				    substream->number,
1444 				    (unsigned long) substream->bytes);
1445 			if (substream->opened) {
1446 				snd_iprintf(buffer,
1447 				    "  Owner PID    : %d\n",
1448 				    pid_vnr(substream->pid));
1449 				runtime = substream->runtime;
1450 				snd_iprintf(buffer,
1451 				    "  Mode         : %s\n"
1452 				    "  Buffer size  : %lu\n"
1453 				    "  Avail        : %lu\n",
1454 				    runtime->oss ? "OSS compatible" : "native",
1455 				    (unsigned long) runtime->buffer_size,
1456 				    (unsigned long) runtime->avail);
1457 			}
1458 		}
1459 	}
1460 	if (rmidi->info_flags & SNDRV_RAWMIDI_INFO_INPUT) {
1461 		list_for_each_entry(substream,
1462 				    &rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT].substreams,
1463 				    list) {
1464 			snd_iprintf(buffer,
1465 				    "Input %d\n"
1466 				    "  Rx bytes     : %lu\n",
1467 				    substream->number,
1468 				    (unsigned long) substream->bytes);
1469 			if (substream->opened) {
1470 				snd_iprintf(buffer,
1471 					    "  Owner PID    : %d\n",
1472 					    pid_vnr(substream->pid));
1473 				runtime = substream->runtime;
1474 				snd_iprintf(buffer,
1475 					    "  Buffer size  : %lu\n"
1476 					    "  Avail        : %lu\n"
1477 					    "  Overruns     : %lu\n",
1478 					    (unsigned long) runtime->buffer_size,
1479 					    (unsigned long) runtime->avail,
1480 					    (unsigned long) runtime->xruns);
1481 			}
1482 		}
1483 	}
1484 	mutex_unlock(&rmidi->open_mutex);
1485 }
1486 
1487 /*
1488  *  Register functions
1489  */
1490 
1491 static const struct file_operations snd_rawmidi_f_ops = {
1492 	.owner =	THIS_MODULE,
1493 	.read =		snd_rawmidi_read,
1494 	.write =	snd_rawmidi_write,
1495 	.open =		snd_rawmidi_open,
1496 	.release =	snd_rawmidi_release,
1497 	.llseek =	no_llseek,
1498 	.poll =		snd_rawmidi_poll,
1499 	.unlocked_ioctl =	snd_rawmidi_ioctl,
1500 	.compat_ioctl =	snd_rawmidi_ioctl_compat,
1501 };
1502 
1503 static int snd_rawmidi_alloc_substreams(struct snd_rawmidi *rmidi,
1504 					struct snd_rawmidi_str *stream,
1505 					int direction,
1506 					int count)
1507 {
1508 	struct snd_rawmidi_substream *substream;
1509 	int idx;
1510 
1511 	for (idx = 0; idx < count; idx++) {
1512 		substream = kzalloc(sizeof(*substream), GFP_KERNEL);
1513 		if (!substream)
1514 			return -ENOMEM;
1515 		substream->stream = direction;
1516 		substream->number = idx;
1517 		substream->rmidi = rmidi;
1518 		substream->pstr = stream;
1519 		list_add_tail(&substream->list, &stream->substreams);
1520 		stream->substream_count++;
1521 	}
1522 	return 0;
1523 }
1524 
1525 static void release_rawmidi_device(struct device *dev)
1526 {
1527 	kfree(container_of(dev, struct snd_rawmidi, dev));
1528 }
1529 
1530 /**
1531  * snd_rawmidi_new - create a rawmidi instance
1532  * @card: the card instance
1533  * @id: the id string
1534  * @device: the device index
1535  * @output_count: the number of output streams
1536  * @input_count: the number of input streams
1537  * @rrawmidi: the pointer to store the new rawmidi instance
1538  *
1539  * Creates a new rawmidi instance.
1540  * Use snd_rawmidi_set_ops() to set the operators to the new instance.
1541  *
1542  * Return: Zero if successful, or a negative error code on failure.
1543  */
1544 int snd_rawmidi_new(struct snd_card *card, char *id, int device,
1545 		    int output_count, int input_count,
1546 		    struct snd_rawmidi **rrawmidi)
1547 {
1548 	struct snd_rawmidi *rmidi;
1549 	int err;
1550 	static struct snd_device_ops ops = {
1551 		.dev_free = snd_rawmidi_dev_free,
1552 		.dev_register = snd_rawmidi_dev_register,
1553 		.dev_disconnect = snd_rawmidi_dev_disconnect,
1554 	};
1555 
1556 	if (snd_BUG_ON(!card))
1557 		return -ENXIO;
1558 	if (rrawmidi)
1559 		*rrawmidi = NULL;
1560 	rmidi = kzalloc(sizeof(*rmidi), GFP_KERNEL);
1561 	if (!rmidi)
1562 		return -ENOMEM;
1563 	rmidi->card = card;
1564 	rmidi->device = device;
1565 	mutex_init(&rmidi->open_mutex);
1566 	init_waitqueue_head(&rmidi->open_wait);
1567 	INIT_LIST_HEAD(&rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT].substreams);
1568 	INIT_LIST_HEAD(&rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substreams);
1569 
1570 	if (id != NULL)
1571 		strlcpy(rmidi->id, id, sizeof(rmidi->id));
1572 
1573 	snd_device_initialize(&rmidi->dev, card);
1574 	rmidi->dev.release = release_rawmidi_device;
1575 	dev_set_name(&rmidi->dev, "midiC%iD%i", card->number, device);
1576 
1577 	err = snd_rawmidi_alloc_substreams(rmidi,
1578 					   &rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT],
1579 					   SNDRV_RAWMIDI_STREAM_INPUT,
1580 					   input_count);
1581 	if (err < 0)
1582 		goto error;
1583 	err = snd_rawmidi_alloc_substreams(rmidi,
1584 					   &rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT],
1585 					   SNDRV_RAWMIDI_STREAM_OUTPUT,
1586 					   output_count);
1587 	if (err < 0)
1588 		goto error;
1589 	err = snd_device_new(card, SNDRV_DEV_RAWMIDI, rmidi, &ops);
1590 	if (err < 0)
1591 		goto error;
1592 
1593 	if (rrawmidi)
1594 		*rrawmidi = rmidi;
1595 	return 0;
1596 
1597  error:
1598 	snd_rawmidi_free(rmidi);
1599 	return err;
1600 }
1601 EXPORT_SYMBOL(snd_rawmidi_new);
1602 
1603 static void snd_rawmidi_free_substreams(struct snd_rawmidi_str *stream)
1604 {
1605 	struct snd_rawmidi_substream *substream;
1606 
1607 	while (!list_empty(&stream->substreams)) {
1608 		substream = list_entry(stream->substreams.next, struct snd_rawmidi_substream, list);
1609 		list_del(&substream->list);
1610 		kfree(substream);
1611 	}
1612 }
1613 
1614 static int snd_rawmidi_free(struct snd_rawmidi *rmidi)
1615 {
1616 	if (!rmidi)
1617 		return 0;
1618 
1619 	snd_info_free_entry(rmidi->proc_entry);
1620 	rmidi->proc_entry = NULL;
1621 	mutex_lock(&register_mutex);
1622 	if (rmidi->ops && rmidi->ops->dev_unregister)
1623 		rmidi->ops->dev_unregister(rmidi);
1624 	mutex_unlock(&register_mutex);
1625 
1626 	snd_rawmidi_free_substreams(&rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT]);
1627 	snd_rawmidi_free_substreams(&rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT]);
1628 	if (rmidi->private_free)
1629 		rmidi->private_free(rmidi);
1630 	put_device(&rmidi->dev);
1631 	return 0;
1632 }
1633 
1634 static int snd_rawmidi_dev_free(struct snd_device *device)
1635 {
1636 	struct snd_rawmidi *rmidi = device->device_data;
1637 
1638 	return snd_rawmidi_free(rmidi);
1639 }
1640 
1641 #if IS_ENABLED(CONFIG_SND_SEQUENCER)
1642 static void snd_rawmidi_dev_seq_free(struct snd_seq_device *device)
1643 {
1644 	struct snd_rawmidi *rmidi = device->private_data;
1645 
1646 	rmidi->seq_dev = NULL;
1647 }
1648 #endif
1649 
1650 static int snd_rawmidi_dev_register(struct snd_device *device)
1651 {
1652 	int err;
1653 	struct snd_info_entry *entry;
1654 	char name[16];
1655 	struct snd_rawmidi *rmidi = device->device_data;
1656 
1657 	if (rmidi->device >= SNDRV_RAWMIDI_DEVICES)
1658 		return -ENOMEM;
1659 	err = 0;
1660 	mutex_lock(&register_mutex);
1661 	if (snd_rawmidi_search(rmidi->card, rmidi->device))
1662 		err = -EBUSY;
1663 	else
1664 		list_add_tail(&rmidi->list, &snd_rawmidi_devices);
1665 	mutex_unlock(&register_mutex);
1666 	if (err < 0)
1667 		return err;
1668 
1669 	err = snd_register_device(SNDRV_DEVICE_TYPE_RAWMIDI,
1670 				  rmidi->card, rmidi->device,
1671 				  &snd_rawmidi_f_ops, rmidi, &rmidi->dev);
1672 	if (err < 0) {
1673 		rmidi_err(rmidi, "unable to register\n");
1674 		goto error;
1675 	}
1676 	if (rmidi->ops && rmidi->ops->dev_register) {
1677 		err = rmidi->ops->dev_register(rmidi);
1678 		if (err < 0)
1679 			goto error_unregister;
1680 	}
1681 #ifdef CONFIG_SND_OSSEMUL
1682 	rmidi->ossreg = 0;
1683 	if ((int)rmidi->device == midi_map[rmidi->card->number]) {
1684 		if (snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI,
1685 					    rmidi->card, 0, &snd_rawmidi_f_ops,
1686 					    rmidi) < 0) {
1687 			rmidi_err(rmidi,
1688 				  "unable to register OSS rawmidi device %i:%i\n",
1689 				  rmidi->card->number, 0);
1690 		} else {
1691 			rmidi->ossreg++;
1692 #ifdef SNDRV_OSS_INFO_DEV_MIDI
1693 			snd_oss_info_register(SNDRV_OSS_INFO_DEV_MIDI, rmidi->card->number, rmidi->name);
1694 #endif
1695 		}
1696 	}
1697 	if ((int)rmidi->device == amidi_map[rmidi->card->number]) {
1698 		if (snd_register_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI,
1699 					    rmidi->card, 1, &snd_rawmidi_f_ops,
1700 					    rmidi) < 0) {
1701 			rmidi_err(rmidi,
1702 				  "unable to register OSS rawmidi device %i:%i\n",
1703 				  rmidi->card->number, 1);
1704 		} else {
1705 			rmidi->ossreg++;
1706 		}
1707 	}
1708 #endif /* CONFIG_SND_OSSEMUL */
1709 	sprintf(name, "midi%d", rmidi->device);
1710 	entry = snd_info_create_card_entry(rmidi->card, name, rmidi->card->proc_root);
1711 	if (entry) {
1712 		entry->private_data = rmidi;
1713 		entry->c.text.read = snd_rawmidi_proc_info_read;
1714 		if (snd_info_register(entry) < 0) {
1715 			snd_info_free_entry(entry);
1716 			entry = NULL;
1717 		}
1718 	}
1719 	rmidi->proc_entry = entry;
1720 #if IS_ENABLED(CONFIG_SND_SEQUENCER)
1721 	if (!rmidi->ops || !rmidi->ops->dev_register) { /* own registration mechanism */
1722 		if (snd_seq_device_new(rmidi->card, rmidi->device, SNDRV_SEQ_DEV_ID_MIDISYNTH, 0, &rmidi->seq_dev) >= 0) {
1723 			rmidi->seq_dev->private_data = rmidi;
1724 			rmidi->seq_dev->private_free = snd_rawmidi_dev_seq_free;
1725 			sprintf(rmidi->seq_dev->name, "MIDI %d-%d", rmidi->card->number, rmidi->device);
1726 			snd_device_register(rmidi->card, rmidi->seq_dev);
1727 		}
1728 	}
1729 #endif
1730 	return 0;
1731 
1732  error_unregister:
1733 	snd_unregister_device(&rmidi->dev);
1734  error:
1735 	mutex_lock(&register_mutex);
1736 	list_del(&rmidi->list);
1737 	mutex_unlock(&register_mutex);
1738 	return err;
1739 }
1740 
1741 static int snd_rawmidi_dev_disconnect(struct snd_device *device)
1742 {
1743 	struct snd_rawmidi *rmidi = device->device_data;
1744 	int dir;
1745 
1746 	mutex_lock(&register_mutex);
1747 	mutex_lock(&rmidi->open_mutex);
1748 	wake_up(&rmidi->open_wait);
1749 	list_del_init(&rmidi->list);
1750 	for (dir = 0; dir < 2; dir++) {
1751 		struct snd_rawmidi_substream *s;
1752 
1753 		list_for_each_entry(s, &rmidi->streams[dir].substreams, list) {
1754 			if (s->runtime)
1755 				wake_up(&s->runtime->sleep);
1756 		}
1757 	}
1758 
1759 #ifdef CONFIG_SND_OSSEMUL
1760 	if (rmidi->ossreg) {
1761 		if ((int)rmidi->device == midi_map[rmidi->card->number]) {
1762 			snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI, rmidi->card, 0);
1763 #ifdef SNDRV_OSS_INFO_DEV_MIDI
1764 			snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_MIDI, rmidi->card->number);
1765 #endif
1766 		}
1767 		if ((int)rmidi->device == amidi_map[rmidi->card->number])
1768 			snd_unregister_oss_device(SNDRV_OSS_DEVICE_TYPE_MIDI, rmidi->card, 1);
1769 		rmidi->ossreg = 0;
1770 	}
1771 #endif /* CONFIG_SND_OSSEMUL */
1772 	snd_unregister_device(&rmidi->dev);
1773 	mutex_unlock(&rmidi->open_mutex);
1774 	mutex_unlock(&register_mutex);
1775 	return 0;
1776 }
1777 
1778 /**
1779  * snd_rawmidi_set_ops - set the rawmidi operators
1780  * @rmidi: the rawmidi instance
1781  * @stream: the stream direction, SNDRV_RAWMIDI_STREAM_XXX
1782  * @ops: the operator table
1783  *
1784  * Sets the rawmidi operators for the given stream direction.
1785  */
1786 void snd_rawmidi_set_ops(struct snd_rawmidi *rmidi, int stream,
1787 			 const struct snd_rawmidi_ops *ops)
1788 {
1789 	struct snd_rawmidi_substream *substream;
1790 
1791 	list_for_each_entry(substream, &rmidi->streams[stream].substreams, list)
1792 		substream->ops = ops;
1793 }
1794 EXPORT_SYMBOL(snd_rawmidi_set_ops);
1795 
1796 /*
1797  *  ENTRY functions
1798  */
1799 
1800 static int __init alsa_rawmidi_init(void)
1801 {
1802 
1803 	snd_ctl_register_ioctl(snd_rawmidi_control_ioctl);
1804 	snd_ctl_register_ioctl_compat(snd_rawmidi_control_ioctl);
1805 #ifdef CONFIG_SND_OSSEMUL
1806 	{ int i;
1807 	/* check device map table */
1808 	for (i = 0; i < SNDRV_CARDS; i++) {
1809 		if (midi_map[i] < 0 || midi_map[i] >= SNDRV_RAWMIDI_DEVICES) {
1810 			pr_err("ALSA: rawmidi: invalid midi_map[%d] = %d\n",
1811 			       i, midi_map[i]);
1812 			midi_map[i] = 0;
1813 		}
1814 		if (amidi_map[i] < 0 || amidi_map[i] >= SNDRV_RAWMIDI_DEVICES) {
1815 			pr_err("ALSA: rawmidi: invalid amidi_map[%d] = %d\n",
1816 			       i, amidi_map[i]);
1817 			amidi_map[i] = 1;
1818 		}
1819 	}
1820 	}
1821 #endif /* CONFIG_SND_OSSEMUL */
1822 	return 0;
1823 }
1824 
1825 static void __exit alsa_rawmidi_exit(void)
1826 {
1827 	snd_ctl_unregister_ioctl(snd_rawmidi_control_ioctl);
1828 	snd_ctl_unregister_ioctl_compat(snd_rawmidi_control_ioctl);
1829 }
1830 
1831 module_init(alsa_rawmidi_init)
1832 module_exit(alsa_rawmidi_exit)
1833