From 7dba48a474e68dcdda2b212cea131b4c9ddc7d89 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 27 Feb 2024 09:53:06 +0100 Subject: [PATCH] ALSA: control_led: Use guard() for locking We can simplify the code gracefully with new guard() macro and co for automatic cleanup of locks. A couple of functions that use snd_card_ref() and *_unref() are also cleaned up with a defined class, too. Only the code refactoring, and no functional changes. Signed-off-by: Takashi Iwai Link: https://lore.kernel.org/r/20240227085306.9764-25-tiwai@suse.de --- sound/core/control_led.c | 150 +++++++++++++++++---------------------- 1 file changed, 65 insertions(+), 85 deletions(-) diff --git a/sound/core/control_led.c b/sound/core/control_led.c index a78eb48927c7..3d37e9fa7b9c 100644 --- a/sound/core/control_led.c +++ b/sound/core/control_led.c @@ -147,29 +147,27 @@ static void snd_ctl_led_set_state(struct snd_card *card, unsigned int access, return; route = -1; found = false; - mutex_lock(&snd_ctl_led_mutex); - /* the card may not be registered (active) at this point */ - if (card && !snd_ctl_led_card_valid[card->number]) { - mutex_unlock(&snd_ctl_led_mutex); - return; - } - list_for_each_entry(lctl, &led->controls, list) { - if (lctl->kctl == kctl && lctl->index_offset == ioff) - found = true; - UPDATE_ROUTE(route, snd_ctl_led_get(lctl)); - } - if (!found && kctl && card) { - lctl = kzalloc(sizeof(*lctl), GFP_KERNEL); - if (lctl) { - lctl->card = card; - lctl->access = access; - lctl->kctl = kctl; - lctl->index_offset = ioff; - list_add(&lctl->list, &led->controls); + scoped_guard(mutex, &snd_ctl_led_mutex) { + /* the card may not be registered (active) at this point */ + if (card && !snd_ctl_led_card_valid[card->number]) + return; + list_for_each_entry(lctl, &led->controls, list) { + if (lctl->kctl == kctl && lctl->index_offset == ioff) + found = true; UPDATE_ROUTE(route, snd_ctl_led_get(lctl)); } + if (!found && kctl && card) { + lctl = kzalloc(sizeof(*lctl), GFP_KERNEL); + if (lctl) { + lctl->card = card; + lctl->access = access; + lctl->kctl = kctl; + lctl->index_offset = ioff; + list_add(&lctl->list, &led->controls); + UPDATE_ROUTE(route, snd_ctl_led_get(lctl)); + } + } } - mutex_unlock(&snd_ctl_led_mutex); switch (led->mode) { case MODE_OFF: route = 1; break; case MODE_ON: route = 0; break; @@ -201,14 +199,13 @@ static unsigned int snd_ctl_led_remove(struct snd_kcontrol *kctl, unsigned int i struct snd_ctl_led_ctl *lctl; unsigned int ret = 0; - mutex_lock(&snd_ctl_led_mutex); + guard(mutex)(&snd_ctl_led_mutex); lctl = snd_ctl_led_find(kctl, ioff); if (lctl && (access == 0 || access != lctl->access)) { ret = lctl->access; list_del(&lctl->list); kfree(lctl); } - mutex_unlock(&snd_ctl_led_mutex); return ret; } @@ -239,44 +236,36 @@ static void snd_ctl_led_notify(struct snd_card *card, unsigned int mask, } } +DEFINE_FREE(snd_card_unref, struct snd_card *, if (_T) snd_card_unref(_T)) + static int snd_ctl_led_set_id(int card_number, struct snd_ctl_elem_id *id, unsigned int group, bool set) { - struct snd_card *card; + struct snd_card *card __free(snd_card_unref) = NULL; struct snd_kcontrol *kctl; struct snd_kcontrol_volatile *vd; unsigned int ioff, access, new_access; - int err = 0; card = snd_card_ref(card_number); - if (card) { - down_write(&card->controls_rwsem); - kctl = snd_ctl_find_id_locked(card, id); - if (kctl) { - ioff = snd_ctl_get_ioff(kctl, id); - vd = &kctl->vd[ioff]; - access = vd->access & SNDRV_CTL_ELEM_ACCESS_LED_MASK; - if (access != 0 && access != group_to_access(group)) { - err = -EXDEV; - goto unlock; - } - new_access = vd->access & ~SNDRV_CTL_ELEM_ACCESS_LED_MASK; - if (set) - new_access |= group_to_access(group); - if (new_access != vd->access) { - vd->access = new_access; - snd_ctl_led_notify(card, SNDRV_CTL_EVENT_MASK_INFO, kctl, ioff); - } - } else { - err = -ENOENT; - } -unlock: - up_write(&card->controls_rwsem); - snd_card_unref(card); - } else { - err = -ENXIO; + if (!card) + return -ENXIO; + guard(rwsem_write)(&card->controls_rwsem); + kctl = snd_ctl_find_id_locked(card, id); + if (!kctl) + return -ENOENT; + ioff = snd_ctl_get_ioff(kctl, id); + vd = &kctl->vd[ioff]; + access = vd->access & SNDRV_CTL_ELEM_ACCESS_LED_MASK; + if (access != 0 && access != group_to_access(group)) + return -EXDEV; + new_access = vd->access & ~SNDRV_CTL_ELEM_ACCESS_LED_MASK; + if (set) + new_access |= group_to_access(group); + if (new_access != vd->access) { + vd->access = new_access; + snd_ctl_led_notify(card, SNDRV_CTL_EVENT_MASK_INFO, kctl, ioff); } - return err; + return 0; } static void snd_ctl_led_refresh(void) @@ -312,7 +301,7 @@ repeat: static int snd_ctl_led_reset(int card_number, unsigned int group) { - struct snd_card *card; + struct snd_card *card __free(snd_card_unref) = NULL; struct snd_ctl_led *led; struct snd_ctl_led_ctl *lctl; struct snd_kcontrol_volatile *vd; @@ -322,26 +311,22 @@ static int snd_ctl_led_reset(int card_number, unsigned int group) if (!card) return -ENXIO; - mutex_lock(&snd_ctl_led_mutex); - if (!snd_ctl_led_card_valid[card_number]) { - mutex_unlock(&snd_ctl_led_mutex); - snd_card_unref(card); - return -ENXIO; - } - led = &snd_ctl_leds[group]; + scoped_guard(mutex, &snd_ctl_led_mutex) { + if (!snd_ctl_led_card_valid[card_number]) + return -ENXIO; + led = &snd_ctl_leds[group]; repeat: - list_for_each_entry(lctl, &led->controls, list) - if (lctl->card == card) { - vd = &lctl->kctl->vd[lctl->index_offset]; - vd->access &= ~group_to_access(group); - snd_ctl_led_ctl_destroy(lctl); - change = true; - goto repeat; - } - mutex_unlock(&snd_ctl_led_mutex); + list_for_each_entry(lctl, &led->controls, list) + if (lctl->card == card) { + vd = &lctl->kctl->vd[lctl->index_offset]; + vd->access &= ~group_to_access(group); + snd_ctl_led_ctl_destroy(lctl); + change = true; + goto repeat; + } + } if (change) snd_ctl_led_set_state(NULL, group_to_access(group), NULL, 0); - snd_card_unref(card); return 0; } @@ -353,9 +338,8 @@ static void snd_ctl_led_register(struct snd_card *card) if (snd_BUG_ON(card->number < 0 || card->number >= ARRAY_SIZE(snd_ctl_led_card_valid))) return; - mutex_lock(&snd_ctl_led_mutex); - snd_ctl_led_card_valid[card->number] = true; - mutex_unlock(&snd_ctl_led_mutex); + scoped_guard(mutex, &snd_ctl_led_mutex) + snd_ctl_led_card_valid[card->number] = true; /* the register callback is already called with held card->controls_rwsem */ list_for_each_entry(kctl, &card->controls, list) for (ioff = 0; ioff < kctl->count; ioff++) @@ -367,10 +351,10 @@ static void snd_ctl_led_register(struct snd_card *card) static void snd_ctl_led_disconnect(struct snd_card *card) { snd_ctl_led_sysfs_remove(card); - mutex_lock(&snd_ctl_led_mutex); - snd_ctl_led_card_valid[card->number] = false; - snd_ctl_led_clean(card); - mutex_unlock(&snd_ctl_led_mutex); + scoped_guard(mutex, &snd_ctl_led_mutex) { + snd_ctl_led_card_valid[card->number] = false; + snd_ctl_led_clean(card); + } snd_ctl_led_refresh(); } @@ -430,9 +414,8 @@ static ssize_t mode_store(struct device *dev, else return count; - mutex_lock(&snd_ctl_led_mutex); - led->mode = mode; - mutex_unlock(&snd_ctl_led_mutex); + scoped_guard(mutex, &snd_ctl_led_mutex) + led->mode = mode; snd_ctl_led_set_state(NULL, group_to_access(led->group), NULL, 0); return count; @@ -615,15 +598,15 @@ static ssize_t list_show(struct device *dev, struct device_attribute *attr, char *buf) { struct snd_ctl_led_card *led_card = container_of(dev, struct snd_ctl_led_card, dev); - struct snd_card *card; + struct snd_card *card __free(snd_card_unref) = NULL; struct snd_ctl_led_ctl *lctl; size_t l = 0; card = snd_card_ref(led_card->number); if (!card) return -ENXIO; - down_read(&card->controls_rwsem); - mutex_lock(&snd_ctl_led_mutex); + guard(rwsem_read)(&card->controls_rwsem); + guard(mutex)(&snd_ctl_led_mutex); if (snd_ctl_led_card_valid[led_card->number]) { list_for_each_entry(lctl, &led_card->led->controls, list) { if (lctl->card != card) @@ -634,9 +617,6 @@ static ssize_t list_show(struct device *dev, lctl->kctl->id.numid + lctl->index_offset); } } - mutex_unlock(&snd_ctl_led_mutex); - up_read(&card->controls_rwsem); - snd_card_unref(card); return l; }