rawmidi.c

linux 内核源代码

		subdevice = -1;
		down_read(&card->controls_rwsem);
		list_for_each_entry(kctl, &card->ctl_files, list) {
			if (kctl->pid == current->pid) {
				subdevice = kctl->prefer_rawmidi_subdevice;
				if (subdevice != -1)
					break;
			}
		}
		up_read(&card->controls_rwsem);
		err = snd_rawmidi_kernel_open(rmidi->card, rmidi->device,
					      subdevice, fflags, rawmidi_file);
		if (err >= 0)
			break;
		if (err == -EAGAIN) {
			if (file->f_flags & O_NONBLOCK) {
				err = -EBUSY;
				break;
			}
		} else
			break;
		set_current_state(TASK_INTERRUPTIBLE);
		mutex_unlock(&rmidi->open_mutex);
		schedule();
		mutex_lock(&rmidi->open_mutex);
		if (signal_pending(current)) {
			err = -ERESTARTSYS;
			break;
		}
	}
#ifdef CONFIG_SND_OSSEMUL
	if (rawmidi_file->input && rawmidi_file->input->runtime)
		rawmidi_file->input->runtime->oss = (maj == SOUND_MAJOR);
	if (rawmidi_file->output && rawmidi_file->output->runtime)
		rawmidi_file->output->runtime->oss = (maj == SOUND_MAJOR);
#endif
	remove_wait_queue(&rmidi->open_wait, &wait);
	if (err >= 0) {
		file->private_data = rawmidi_file;
	} else {
		snd_card_file_remove(card, file);
		kfree(rawmidi_file);
	}
	mutex_unlock(&rmidi->open_mutex);
	return err;
}

int snd_rawmidi_kernel_release(struct snd_rawmidi_file * rfile)
{
	struct snd_rawmidi *rmidi;
	struct snd_rawmidi_substream *substream;
	struct snd_rawmidi_runtime *runtime;

	snd_assert(rfile != NULL, return -ENXIO);
	snd_assert(rfile->input != NULL || rfile->output != NULL, return -ENXIO);
	rmidi = rfile->rmidi;
	mutex_lock(&rmidi->open_mutex);
	if (rfile->input != NULL) {
		substream = rfile->input;
		rfile->input = NULL;
		runtime = substream->runtime;
		snd_rawmidi_input_trigger(substream, 0);
		substream->ops->close(substream);
		if (runtime->private_free != NULL)
			runtime->private_free(substream);
		snd_rawmidi_runtime_free(substream);
		substream->opened = 0;
		rmidi->streams[SNDRV_RAWMIDI_STREAM_INPUT].substream_opened--;
	}
	if (rfile->output != NULL) {
		substream = rfile->output;
		rfile->output = NULL;
		if (--substream->use_count == 0) {
			runtime = substream->runtime;
			if (substream->active_sensing) {
				unsigned char buf = 0xfe;
				/* sending single active sensing message to shut the device up */
				snd_rawmidi_kernel_write(substream, &buf, 1);
			}
			if (snd_rawmidi_drain_output(substream) == -ERESTARTSYS)
				snd_rawmidi_output_trigger(substream, 0);
			substream->ops->close(substream);
			if (runtime->private_free != NULL)
				runtime->private_free(substream);
			snd_rawmidi_runtime_free(substream);
			substream->opened = 0;
			substream->append = 0;
		}
		rmidi->streams[SNDRV_RAWMIDI_STREAM_OUTPUT].substream_opened--;
	}
	mutex_unlock(&rmidi->open_mutex);
	module_put(rmidi->card->module);
	return 0;
}

static int snd_rawmidi_release(struct inode *inode, struct file *file)
{
	struct snd_rawmidi_file *rfile;
	struct snd_rawmidi *rmidi;
	int err;

	rfile = file->private_data;
	err = snd_rawmidi_kernel_release(rfile);
	rmidi = rfile->rmidi;
	wake_up(&rmidi->open_wait);
	kfree(rfile);
	snd_card_file_remove(rmidi->card, file);
	return err;
}

static int snd_rawmidi_info(struct snd_rawmidi_substream *substream,
			    struct snd_rawmidi_info *info)
{
	struct snd_rawmidi *rmidi;
	
	if (substream == NULL)
		return -ENODEV;
	rmidi = substream->rmidi;
	memset(info, 0, sizeof(*info));
	info->card = rmidi->card->number;
	info->device = rmidi->device;
	info->subdevice = substream->number;
	info->stream = substream->stream;
	info->flags = rmidi->info_flags;
	strcpy(info->id, rmidi->id);
	strcpy(info->name, rmidi->name);
	strcpy(info->subname, substream->name);
	info->subdevices_count = substream->pstr->substream_count;
	info->subdevices_avail = (substream->pstr->substream_count -
				  substream->pstr->substream_opened);
	return 0;
}

static int snd_rawmidi_info_user(struct snd_rawmidi_substream *substream,
				 struct snd_rawmidi_info __user * _info)
{
	struct snd_rawmidi_info info;
	int err;
	if ((err = snd_rawmidi_info(substream, &info)) < 0)
		return err;
	if (copy_to_user(_info, &info, sizeof(struct snd_rawmidi_info)))
		return -EFAULT;
	return 0;
}

int snd_rawmidi_info_select(struct snd_card *card, struct snd_rawmidi_info *info)
{
	struct snd_rawmidi *rmidi;
	struct snd_rawmidi_str *pstr;
	struct snd_rawmidi_substream *substream;

	mutex_lock(&register_mutex);
	rmidi = snd_rawmidi_search(card, info->device);
	mutex_unlock(&register_mutex);
	if (!rmidi)
		return -ENXIO;
	if (info->stream < 0 || info->stream > 1)
		return -EINVAL;
	pstr = &rmidi->streams[info->stream];
	if (pstr->substream_count == 0)
		return -ENOENT;
	if (info->subdevice >= pstr->substream_count)
		return -ENXIO;
	list_for_each_entry(substream, &pstr->substreams, list) {
		if ((unsigned int)substream->number == info->subdevice)
			return snd_rawmidi_info(substream, info);
	}
	return -ENXIO;
}

static int snd_rawmidi_info_select_user(struct snd_card *card,
					struct snd_rawmidi_info __user *_info)
{
	int err;
	struct snd_rawmidi_info info;
	if (get_user(info.device, &_info->device))
		return -EFAULT;
	if (get_user(info.stream, &_info->stream))
		return -EFAULT;
	if (get_user(info.subdevice, &_info->subdevice))
		return -EFAULT;
	if ((err = snd_rawmidi_info_select(card, &info)) < 0)
		return err;
	if (copy_to_user(_info, &info, sizeof(struct snd_rawmidi_info)))
		return -EFAULT;
	return 0;
}

int snd_rawmidi_output_params(struct snd_rawmidi_substream *substream,
			      struct snd_rawmidi_params * params)
{
	char *newbuf;
	struct snd_rawmidi_runtime *runtime = substream->runtime;
	
	if (substream->append && substream->use_count > 1)
		return -EBUSY;
	snd_rawmidi_drain_output(substream);
	if (params->buffer_size < 32 || params->buffer_size > 1024L * 1024L) {
		return -EINVAL;
	}
	if (params->avail_min < 1 || params->avail_min > params->buffer_size) {
		return -EINVAL;
	}
	if (params->buffer_size != runtime->buffer_size) {
		newbuf = kmalloc(params->buffer_size, GFP_KERNEL);
		if (!newbuf)
			return -ENOMEM;
		kfree(runtime->buffer);
		runtime->buffer = newbuf;
		runtime->buffer_size = params->buffer_size;
		runtime->avail = runtime->buffer_size;
	}
	runtime->avail_min = params->avail_min;
	substream->active_sensing = !params->no_active_sensing;
	return 0;
}

int snd_rawmidi_input_params(struct snd_rawmidi_substream *substream,
			     struct snd_rawmidi_params * params)
{
	char *newbuf;
	struct snd_rawmidi_runtime *runtime = substream->runtime;

	snd_rawmidi_drain_input(substream);
	if (params->buffer_size < 32 || params->buffer_size > 1024L * 1024L) {
		return -EINVAL;
	}
	if (params->avail_min < 1 || params->avail_min > params->buffer_size) {
		return -EINVAL;
	}
	if (params->buffer_size != runtime->buffer_size) {
		newbuf = kmalloc(params->buffer_size, GFP_KERNEL);
		if (!newbuf)
			return -ENOMEM;
		kfree(runtime->buffer);
		runtime->buffer = newbuf;
		runtime->buffer_size = params->buffer_size;
	}
	runtime->avail_min = params->avail_min;
	return 0;
}

static int snd_rawmidi_output_status(struct snd_rawmidi_substream *substream,
				     struct snd_rawmidi_status * status)
{
	struct snd_rawmidi_runtime *runtime = substream->runtime;

	memset(status, 0, sizeof(*status));
	status->stream = SNDRV_RAWMIDI_STREAM_OUTPUT;
	spin_lock_irq(&runtime->lock);
	status->avail = runtime->avail;
	spin_unlock_irq(&runtime->lock);
	return 0;
}

static int snd_rawmidi_input_status(struct snd_rawmidi_substream *substream,
				    struct snd_rawmidi_status * status)
{
	struct snd_rawmidi_runtime *runtime = substream->runtime;

	memset(status, 0, sizeof(*status));
	status->stream = SNDRV_RAWMIDI_STREAM_INPUT;
	spin_lock_irq(&runtime->lock);
	status->avail = runtime->avail;
	status->xruns = runtime->xruns;
	runtime->xruns = 0;
	spin_unlock_irq(&runtime->lock);
	return 0;
}

static long snd_rawmidi_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	struct snd_rawmidi_file *rfile;
	void __user *argp = (void __user *)arg;

	rfile = file->private_data;
	if (((cmd >> 8) & 0xff) != 'W')
		return -ENOTTY;
	switch (cmd) {
	case SNDRV_RAWMIDI_IOCTL_PVERSION:
		return put_user(SNDRV_RAWMIDI_VERSION, (int __user *)argp) ? -EFAULT : 0;
	case SNDRV_RAWMIDI_IOCTL_INFO:
	{
		int stream;
		struct snd_rawmidi_info __user *info = argp;
		if (get_user(stream, &info->stream))
			return -EFAULT;
		switch (stream) {
		case SNDRV_RAWMIDI_STREAM_INPUT:
			return snd_rawmidi_info_user(rfile->input, info);
		case SNDRV_RAWMIDI_STREAM_OUTPUT:
			return snd_rawmidi_info_user(rfile->output, info);
		default:
			return -EINVAL;
		}
	}
	case SNDRV_RAWMIDI_IOCTL_PARAMS:
	{
		struct snd_rawmidi_params params;
		if (copy_from_user(&params, argp, sizeof(struct snd_rawmidi_params)))
			return -EFAULT;
		switch (params.stream) {
		case SNDRV_RAWMIDI_STREAM_OUTPUT:
			if (rfile->output == NULL)
				return -EINVAL;
			return snd_rawmidi_output_params(rfile->output, &params);
		case SNDRV_RAWMIDI_STREAM_INPUT:
			if (rfile->input == NULL)
				return -EINVAL;
			return snd_rawmidi_input_params(rfile->input, &params);
		default:
			return -EINVAL;
		}
	}
	case SNDRV_RAWMIDI_IOCTL_STATUS:
	{
		int err = 0;
		struct snd_rawmidi_status status;
		if (copy_from_user(&status, argp, sizeof(struct snd_rawmidi_status)))
			return -EFAULT;
		switch (status.stream) {
		case SNDRV_RAWMIDI_STREAM_OUTPUT:
			if (rfile->output == NULL)
				return -EINVAL;
			err = snd_rawmidi_output_status(rfile->output, &status);
			break;
		case SNDRV_RAWMIDI_STREAM_INPUT:
			if (rfile->input == NULL)
				return -EINVAL;
			err = snd_rawmidi_input_status(rfile->input, &status);
			break;
		default:
			return -EINVAL;
		}
		if (err < 0)
			return err;
		if (copy_to_user(argp, &status, sizeof(struct snd_rawmidi_status)))
			return -EFAULT;
		return 0;
	}
	case SNDRV_RAWMIDI_IOCTL_DROP:
	{
		int val;
		if (get_user(val, (int __user *) argp))
			return -EFAULT;
		switch (val) {
		case SNDRV_RAWMIDI_STREAM_OUTPUT:
			if (rfile->output == NULL)
				return -EINVAL;
			return snd_rawmidi_drop_output(rfile->output);
		default:
			return -EINVAL;
		}
	}
	case SNDRV_RAWMIDI_IOCTL_DRAIN:
	{
		int val;
		if (get_user(val, (int __user *) argp))
			return -EFAULT;
		switch (val) {
		case SNDRV_RAWMIDI_STREAM_OUTPUT:
			if (rfile->output == NULL)
				return -EINVAL;
			return snd_rawmidi_drain_output(rfile->output);
		case SNDRV_RAWMIDI_STREAM_INPUT:
			if (rfile->input == NULL)
				return -EINVAL;
			return snd_rawmidi_drain_input(rfile->input);
		default:
			return -EINVAL;
		}
	}
#ifdef CONFIG_SND_DEBUG
	default:
		snd_printk(KERN_WARNING "rawmidi: unknown command = 0x%x\n", cmd);
#endif
	}
	return -ENOTTY;
}

static int snd_rawmidi_control_ioctl(struct snd_card *card,
				     struct snd_ctl_file *control,
				     unsigned int cmd,
				     unsigned long arg)
{
	void __user *argp = (void __user *)arg;

	switch (cmd) {
	case SNDRV_CTL_IOCTL_RAWMIDI_NEXT_DEVICE:
	{
		int device;
		
		if (get_user(device, (int __user *)argp))
			return -EFAULT;
		mutex_lock(&register_mutex);
		device = device < 0 ? 0 : device + 1;
		while (device < SNDRV_RAWMIDI_DEVICES) {
			if (snd_rawmidi_search(card, device))
				break;
			device++;
		}
		if (device == SNDRV_RAWMIDI_DEVICES)
			device = -1;
		mutex_unlock(&register_mutex);
		if (put_user(device, (int __user *)argp))
			return -EFAULT;
		return 0;
	}
	case SNDRV_CTL_IOCTL_RAWMIDI_PREFER_SUBDEVICE:
	{
		int val;
		
		if (get_user(val, (int __user *)argp))
			return -EFAULT;
		control->prefer_rawmidi_subdevice = val;
		return 0;
	}
	case SNDRV_CTL_IOCTL_RAWMIDI_INFO:
		return snd_rawmidi_info_select_user(card, argp);
	}