redonkable/remarkable-linux
redonkable/remarkable-linux
1
0
Fork 0
Code Releases Activity

ALSA: Core - clean up snd_card_set_id* calls and remove possible id collision

Browse source 
Move locking outside snd_card_set_id_internal() function and rename it
to snd_card_set_id_no_lock() for better function description.

User defined id is just copied to card structure at allocation time.
The real unique id procedure is called in snd_card_register() to
ensure real atomicity.

Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Jaroslav Kysela 2009-06-04 00:12:18 +02:00 committed by Takashi Iwai
parent 872c78202c
commit 5fdc18d938
1 changed files with 10 additions and 16 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

26
sound/core/init.c
View file

@ -153,7 +153,7 @@ int snd_card_create(int idx, const char *xid,
if (!card)
return -ENOMEM;
if (xid)
snd_card_set_id(card, xid);
strlcpy(card->id, xid, sizeof(card->id));
err = 0;
mutex_lock(&snd_card_mutex);
if (idx < 0) {
@ -476,16 +476,12 @@ int snd_card_free(struct snd_card *card)
EXPORT_SYMBOL(snd_card_free);
static void snd_card_set_id_internal(struct snd_card *card, const char *nid,
int do_locking)
static void snd_card_set_id_no_lock(struct snd_card *card, const char *nid)
{
int i, len, idx_flag = 0, loops = SNDRV_CARDS;
const char *spos, *src;
char *id;
/* check if user specified own card->id */
if (card->id[0] != '\0')
return;
if (nid == NULL) {
id = card->shortname;
spos = src = id;
@ -522,16 +518,10 @@ static void snd_card_set_id_internal(struct snd_card *card, const char *nid,
}
if (!snd_info_check_reserved_words(id))
goto __change;
if (do_locking)
mutex_lock(&snd_card_mutex);
for (i = 0; i < snd_ecards_limit; i++) {
if (snd_cards[i] && !strcmp(snd_cards[i]->id, id)) {
mutex_unlock(&snd_card_mutex);
if (snd_cards[i] && !strcmp(snd_cards[i]->id, id))
goto __change;
}
}
if (do_locking)
mutex_unlock(&snd_card_mutex);
break;
__change:
@ -566,7 +556,12 @@ static void snd_card_set_id_internal(struct snd_card *card, const char *nid,
*/
void snd_card_set_id(struct snd_card *card, const char *nid)
{
snd_card_set_id_internal(card, nid, 1);
/* check if user specified own card->id */
if (card->id[0] != '\0')
return;
mutex_lock(&snd_card_mutex);
snd_card_set_id_no_lock(card, nid);
mutex_unlock(&snd_card_mutex);
}
EXPORT_SYMBOL(snd_card_set_id);
@ -663,8 +658,7 @@ int snd_card_register(struct snd_card *card)
mutex_unlock(&snd_card_mutex);
return 0;
}
if (card->id[0] == '\0')
snd_card_set_id_internal(card, NULL, 0);
snd_card_set_id_no_lock(card, card->id[0] == '\0' ? NULL : card->id);
snd_cards[card->number] = card;
mutex_unlock(&snd_card_mutex);
init_info_for_card(card);