From e6684d08cc1935774b07efc262e70b41ac1c0f93 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 27 Feb 2024 09:52:47 +0100 Subject: [PATCH] ALSA: hwdep: Use guard() for locking We can simplify the code gracefully with new guard() macro and co for automatic cleanup of locks. There are still a few remaining explicit mutex_lock/unlock calls, and those are for the places where we do temporary unlock/relock, which doesn't fit well with the guard(), so far. Only the code refactoring, and no functional changes. Signed-off-by: Takashi Iwai Link: https://lore.kernel.org/r/20240227085306.9764-6-tiwai@suse.de --- sound/core/hwdep.c | 85 +++++++++++++++++++++------------------------- 1 file changed, 38 insertions(+), 47 deletions(-) diff --git a/sound/core/hwdep.c b/sound/core/hwdep.c index de7476034f2c..9d7e5039c893 100644 --- a/sound/core/hwdep.c +++ b/sound/core/hwdep.c @@ -149,12 +149,12 @@ static int snd_hwdep_release(struct inode *inode, struct file * file) struct snd_hwdep *hw = file->private_data; struct module *mod = hw->card->module; - mutex_lock(&hw->open_mutex); - if (hw->ops.release) - err = hw->ops.release(hw, file); - if (hw->used > 0) - hw->used--; - mutex_unlock(&hw->open_mutex); + scoped_guard(mutex, &hw->open_mutex) { + if (hw->ops.release) + err = hw->ops.release(hw, file); + if (hw->used > 0) + hw->used--; + } wake_up(&hw->open_wait); snd_card_file_remove(hw->card, file); @@ -272,43 +272,43 @@ static int snd_hwdep_control_ioctl(struct snd_card *card, if (get_user(device, (int __user *)arg)) return -EFAULT; - mutex_lock(®ister_mutex); - if (device < 0) - device = 0; - else if (device < SNDRV_MINOR_HWDEPS) - device++; - else - device = SNDRV_MINOR_HWDEPS; + scoped_guard(mutex, ®ister_mutex) { + if (device < 0) + device = 0; + else if (device < SNDRV_MINOR_HWDEPS) + device++; + else + device = SNDRV_MINOR_HWDEPS; - while (device < SNDRV_MINOR_HWDEPS) { - if (snd_hwdep_search(card, device)) - break; - device++; + while (device < SNDRV_MINOR_HWDEPS) { + if (snd_hwdep_search(card, device)) + break; + device++; + } + if (device >= SNDRV_MINOR_HWDEPS) + device = -1; + if (put_user(device, (int __user *)arg)) + return -EFAULT; + return 0; } - if (device >= SNDRV_MINOR_HWDEPS) - device = -1; - mutex_unlock(®ister_mutex); - if (put_user(device, (int __user *)arg)) - return -EFAULT; - return 0; + break; } case SNDRV_CTL_IOCTL_HWDEP_INFO: { struct snd_hwdep_info __user *info = (struct snd_hwdep_info __user *)arg; - int device, err; + int device; struct snd_hwdep *hwdep; if (get_user(device, &info->device)) return -EFAULT; - mutex_lock(®ister_mutex); - hwdep = snd_hwdep_search(card, device); - if (hwdep) - err = snd_hwdep_info(hwdep, info); - else - err = -ENXIO; - mutex_unlock(®ister_mutex); - return err; + scoped_guard(mutex, ®ister_mutex) { + hwdep = snd_hwdep_search(card, device); + if (!hwdep) + return -ENXIO; + return snd_hwdep_info(hwdep, info); + } + break; } } return -ENOIOCTLCMD; @@ -422,11 +422,9 @@ static int snd_hwdep_dev_register(struct snd_device *device) struct snd_card *card = hwdep->card; int err; - mutex_lock(®ister_mutex); - if (snd_hwdep_search(card, hwdep->device)) { - mutex_unlock(®ister_mutex); + guard(mutex)(®ister_mutex); + if (snd_hwdep_search(card, hwdep->device)) return -EBUSY; - } list_add_tail(&hwdep->list, &snd_hwdep_devices); err = snd_register_device(SNDRV_DEVICE_TYPE_HWDEP, hwdep->card, hwdep->device, @@ -434,7 +432,6 @@ static int snd_hwdep_dev_register(struct snd_device *device) if (err < 0) { dev_err(hwdep->dev, "unable to register\n"); list_del(&hwdep->list); - mutex_unlock(®ister_mutex); return err; } @@ -454,7 +451,6 @@ static int snd_hwdep_dev_register(struct snd_device *device) hwdep->ossreg = 1; } #endif - mutex_unlock(®ister_mutex); return 0; } @@ -464,12 +460,10 @@ static int snd_hwdep_dev_disconnect(struct snd_device *device) if (snd_BUG_ON(!hwdep)) return -ENXIO; - mutex_lock(®ister_mutex); - if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) { - mutex_unlock(®ister_mutex); + guard(mutex)(®ister_mutex); + if (snd_hwdep_search(hwdep->card, hwdep->device) != hwdep) return -EINVAL; - } - mutex_lock(&hwdep->open_mutex); + guard(mutex)(&hwdep->open_mutex); wake_up(&hwdep->open_wait); #ifdef CONFIG_SND_OSSEMUL if (hwdep->ossreg) @@ -477,8 +471,6 @@ static int snd_hwdep_dev_disconnect(struct snd_device *device) #endif snd_unregister_device(hwdep->dev); list_del_init(&hwdep->list); - mutex_unlock(&hwdep->open_mutex); - mutex_unlock(®ister_mutex); return 0; } @@ -492,11 +484,10 @@ static void snd_hwdep_proc_read(struct snd_info_entry *entry, { struct snd_hwdep *hwdep; - mutex_lock(®ister_mutex); + guard(mutex)(®ister_mutex); list_for_each_entry(hwdep, &snd_hwdep_devices, list) snd_iprintf(buffer, "%02i-%02i: %s\n", hwdep->card->number, hwdep->device, hwdep->name); - mutex_unlock(®ister_mutex); } static struct snd_info_entry *snd_hwdep_proc_entry;