Commit 4ed56666 authored by Takashi Sakamoto's avatar Takashi Sakamoto Committed by Takashi Iwai
Browse files

ALSA: core: use precomputed table to check userspace control params 



The parameters can be decided in compile time.

This commit adds precomputed table to reduce calculating time.

Signed-off-by: default avatarTakashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent ce991981

sound/core/control.c

+28 −32
Original line number Diff line number Diff line
@@ -1161,6 +1161,23 @@ static void snd_ctl_elem_user_free(struct snd_kcontrol *kcontrol) 
static int snd_ctl_elem_add(struct snd_ctl_file *file,

			    struct snd_ctl_elem_info *info, int replace)

{

	/* The capacity of struct snd_ctl_elem_value.value.*/

	static const unsigned int value_sizes[] = {

		[SNDRV_CTL_ELEM_TYPE_BOOLEAN]	= sizeof(long),

		[SNDRV_CTL_ELEM_TYPE_INTEGER]	= sizeof(long),

		[SNDRV_CTL_ELEM_TYPE_ENUMERATED] = sizeof(unsigned int),

		[SNDRV_CTL_ELEM_TYPE_BYTES]	= sizeof(unsigned char),

		[SNDRV_CTL_ELEM_TYPE_IEC958]	= sizeof(struct snd_aes_iec958),

		[SNDRV_CTL_ELEM_TYPE_INTEGER64] = sizeof(long long),

	};

	static const unsigned int max_value_counts[] = {

		[SNDRV_CTL_ELEM_TYPE_BOOLEAN]	= 128,

		[SNDRV_CTL_ELEM_TYPE_INTEGER]	= 128,

		[SNDRV_CTL_ELEM_TYPE_ENUMERATED] = 128,

		[SNDRV_CTL_ELEM_TYPE_BYTES]	= 512,

		[SNDRV_CTL_ELEM_TYPE_IEC958]	= 1,

		[SNDRV_CTL_ELEM_TYPE_INTEGER64] = 64,

	};

	struct snd_card *card = file->card;

	struct snd_kcontrol kctl, *_kctl;

	unsigned int access;
@@ -1168,8 +1185,6 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file, 
	struct user_element *ue;

	int idx, err;



	if (info->count < 1)

		return -EINVAL;

	access = info->access == 0 ? SNDRV_CTL_ELEM_ACCESS_READWRITE :

		(info->access & (SNDRV_CTL_ELEM_ACCESS_READWRITE|

				 SNDRV_CTL_ELEM_ACCESS_INACTIVE|
@@ -1201,37 +1216,18 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file, 
		kctl.tlv.c = snd_ctl_elem_user_tlv;

		access |= SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;

	}

	switch (info->type) {

	case SNDRV_CTL_ELEM_TYPE_BOOLEAN:

	case SNDRV_CTL_ELEM_TYPE_INTEGER:

		private_size = sizeof(long);

		if (info->count > 128)

			return -EINVAL;

		break;

	case SNDRV_CTL_ELEM_TYPE_INTEGER64:

		private_size = sizeof(long long);

		if (info->count > 64)

			return -EINVAL;

		break;

	case SNDRV_CTL_ELEM_TYPE_ENUMERATED:

		private_size = sizeof(unsigned int);

		if (info->count > 128 || info->value.enumerated.items == 0)



	if (info->type < SNDRV_CTL_ELEM_TYPE_BOOLEAN ||

	    info->type > SNDRV_CTL_ELEM_TYPE_INTEGER64)

		return -EINVAL;

		break;

	case SNDRV_CTL_ELEM_TYPE_BYTES:

		private_size = sizeof(unsigned char);

		if (info->count > 512)

	if (info->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED &&

	    info->value.enumerated.items == 0)

		return -EINVAL;

		break;

	case SNDRV_CTL_ELEM_TYPE_IEC958:

		private_size = sizeof(struct snd_aes_iec958);

		if (info->count != 1)

	if (info->count < 1 ||

	    info->count > max_value_counts[info->type])

		return -EINVAL;

		break;

	default:

		return -EINVAL;

	}

	private_size *= info->count;



	private_size = value_sizes[info->type] * info->count;

	ue = kzalloc(sizeof(struct user_element) + private_size, GFP_KERNEL);

	if (ue == NULL)

		return -ENOMEM;