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dkim=pass header.d=suse.de header.s=susede2_rsa header.b=CfFZAmtT; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=Kd3rIoXj X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Spamd-Result: default: False [-1.51 / 50.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FROM_HAS_DN(0.00)[]; DWL_DNSWL_MED(-2.00)[suse.de:dkim]; R_MISSING_CHARSET(2.50)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; TO_DN_NONE(0.00)[]; BROKEN_CONTENT_TYPE(1.50)[]; RCPT_COUNT_ONE(0.00)[1]; NEURAL_HAM_LONG(-1.00)[-1.000]; RCVD_COUNT_THREE(0.00)[3]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; DKIM_TRACE(0.00)[suse.de:+]; MX_GOOD(-0.01)[]; MID_CONTAINS_FROM(1.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:dkim,suse.de:email]; FUZZY_BLOCKED(0.00)[rspamd.com]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; NEURAL_HAM_SHORT(-0.20)[-0.992]; RCVD_TLS_ALL(0.00)[]; BAYES_HAM(-3.00)[100.00%] X-Spam-Score: -1.51 X-Rspamd-Queue-Id: 8F9771FCD6 X-Spam-Flag: NO We can simplify the code gracefully with new guard() macro and co for automatic cleanup of locks. The lops calls under multiple rwsems are factored out as a simple macro, so that it can be called easily from snd_ctl_dev_register() and snd_ctl_dev_disconnect(). There are a few remaining explicit rwsem and spinlock calls, and those are the places where the lock downgrade happens or where the temporary unlock/relocking happens -- which guard() doens't cover well yet. Only the code refactoring, and no functional changes. Signed-off-by: Takashi Iwai --- sound/core/control.c | 429 +++++++++++++++++-------------------------- 1 file changed, 171 insertions(+), 258 deletions(-) diff --git a/sound/core/control.c b/sound/core/control.c index c8cd70aed6af..d45428dbdfb0 100644 --- a/sound/core/control.c +++ b/sound/core/control.c @@ -44,7 +44,6 @@ static int snd_ctl_remove_locked(struct snd_card *card, static int snd_ctl_open(struct inode *inode, struct file *file) { - unsigned long flags; struct snd_card *card; struct snd_ctl_file *ctl; int i, err; @@ -80,9 +79,8 @@ static int snd_ctl_open(struct inode *inode, struct file *file) ctl->preferred_subdevice[i] = -1; ctl->pid = get_pid(task_pid(current)); file->private_data = ctl; - write_lock_irqsave(&card->ctl_files_rwlock, flags); - list_add_tail(&ctl->list, &card->ctl_files); - write_unlock_irqrestore(&card->ctl_files_rwlock, flags); + scoped_guard(write_lock_irqsave, &card->ctl_files_rwlock) + list_add_tail(&ctl->list, &card->ctl_files); snd_card_unref(card); return 0; @@ -98,21 +96,18 @@ static int snd_ctl_open(struct inode *inode, struct file *file) static void snd_ctl_empty_read_queue(struct snd_ctl_file * ctl) { - unsigned long flags; struct snd_kctl_event *cread; - spin_lock_irqsave(&ctl->read_lock, flags); + guard(spinlock_irqsave)(&ctl->read_lock); while (!list_empty(&ctl->events)) { cread = snd_kctl_event(ctl->events.next); list_del(&cread->list); kfree(cread); } - spin_unlock_irqrestore(&ctl->read_lock, flags); } static int snd_ctl_release(struct inode *inode, struct file *file) { - unsigned long flags; struct snd_card *card; struct snd_ctl_file *ctl; struct snd_kcontrol *control; @@ -121,15 +116,17 @@ static int snd_ctl_release(struct inode *inode, struct file *file) ctl = file->private_data; file->private_data = NULL; card = ctl->card; - write_lock_irqsave(&card->ctl_files_rwlock, flags); - list_del(&ctl->list); - write_unlock_irqrestore(&card->ctl_files_rwlock, flags); - down_write(&card->controls_rwsem); - list_for_each_entry(control, &card->controls, list) - for (idx = 0; idx < control->count; idx++) - if (control->vd[idx].owner == ctl) - control->vd[idx].owner = NULL; - up_write(&card->controls_rwsem); + + scoped_guard(write_lock_irqsave, &card->ctl_files_rwlock) + list_del(&ctl->list); + + scoped_guard(rwsem_write, &card->controls_rwsem) { + list_for_each_entry(control, &card->controls, list) + for (idx = 0; idx < control->count; idx++) + if (control->vd[idx].owner == ctl) + control->vd[idx].owner = NULL; + } + snd_fasync_free(ctl->fasync); snd_ctl_empty_read_queue(ctl); put_pid(ctl->pid); @@ -152,7 +149,6 @@ static int snd_ctl_release(struct inode *inode, struct file *file) void snd_ctl_notify(struct snd_card *card, unsigned int mask, struct snd_ctl_elem_id *id) { - unsigned long flags; struct snd_ctl_file *ctl; struct snd_kctl_event *ev; @@ -160,34 +156,34 @@ void snd_ctl_notify(struct snd_card *card, unsigned int mask, return; if (card->shutdown) return; - read_lock_irqsave(&card->ctl_files_rwlock, flags); + + guard(read_lock_irqsave)(&card->ctl_files_rwlock); #if IS_ENABLED(CONFIG_SND_MIXER_OSS) card->mixer_oss_change_count++; #endif list_for_each_entry(ctl, &card->ctl_files, list) { if (!ctl->subscribed) continue; - spin_lock(&ctl->read_lock); - list_for_each_entry(ev, &ctl->events, list) { - if (ev->id.numid == id->numid) { - ev->mask |= mask; - goto _found; + scoped_guard(spinlock, &ctl->read_lock) { + list_for_each_entry(ev, &ctl->events, list) { + if (ev->id.numid == id->numid) { + ev->mask |= mask; + goto _found; + } } + ev = kzalloc(sizeof(*ev), GFP_ATOMIC); + if (ev) { + ev->id = *id; + ev->mask = mask; + list_add_tail(&ev->list, &ctl->events); + } else { + dev_err(card->dev, "No memory available to allocate event\n"); + } +_found: + wake_up(&ctl->change_sleep); } - ev = kzalloc(sizeof(*ev), GFP_ATOMIC); - if (ev) { - ev->id = *id; - ev->mask = mask; - list_add_tail(&ev->list, &ctl->events); - } else { - dev_err(card->dev, "No memory available to allocate event\n"); - } - _found: - wake_up(&ctl->change_sleep); - spin_unlock(&ctl->read_lock); snd_kill_fasync(ctl->fasync, SIGIO, POLL_IN); } - read_unlock_irqrestore(&card->ctl_files_rwlock, flags); } EXPORT_SYMBOL(snd_ctl_notify); @@ -210,10 +206,9 @@ void snd_ctl_notify_one(struct snd_card *card, unsigned int mask, id.index += ioff; id.numid += ioff; snd_ctl_notify(card, mask, &id); - down_read(&snd_ctl_layer_rwsem); + guard(rwsem_read)(&snd_ctl_layer_rwsem); for (lops = snd_ctl_layer; lops; lops = lops->next) lops->lnotify(card, mask, kctl, ioff); - up_read(&snd_ctl_layer_rwsem); } EXPORT_SYMBOL(snd_ctl_notify_one); @@ -520,9 +515,9 @@ static int snd_ctl_add_replace(struct snd_card *card, if (snd_BUG_ON(!card || !kcontrol->info)) goto error; - down_write(&card->controls_rwsem); - err = __snd_ctl_add_replace(card, kcontrol, mode); - up_write(&card->controls_rwsem); + scoped_guard(rwsem_write, &card->controls_rwsem) + err = __snd_ctl_add_replace(card, kcontrol, mode); + if (err < 0) goto error; return 0; @@ -616,12 +611,8 @@ static inline int snd_ctl_remove_locked(struct snd_card *card, */ int snd_ctl_remove(struct snd_card *card, struct snd_kcontrol *kcontrol) { - int ret; - - down_write(&card->controls_rwsem); - ret = snd_ctl_remove_locked(card, kcontrol); - up_write(&card->controls_rwsem); - return ret; + guard(rwsem_write)(&card->controls_rwsem); + return snd_ctl_remove_locked(card, kcontrol); } EXPORT_SYMBOL(snd_ctl_remove); @@ -638,17 +629,12 @@ EXPORT_SYMBOL(snd_ctl_remove); int snd_ctl_remove_id(struct snd_card *card, struct snd_ctl_elem_id *id) { struct snd_kcontrol *kctl; - int ret; - down_write(&card->controls_rwsem); + guard(rwsem_write)(&card->controls_rwsem); kctl = snd_ctl_find_id_locked(card, id); - if (kctl == NULL) { - up_write(&card->controls_rwsem); + if (kctl == NULL) return -ENOENT; - } - ret = snd_ctl_remove_locked(card, kctl); - up_write(&card->controls_rwsem); - return ret; + return snd_ctl_remove_locked(card, kctl); } EXPORT_SYMBOL(snd_ctl_remove_id); @@ -667,27 +653,18 @@ static int snd_ctl_remove_user_ctl(struct snd_ctl_file * file, { struct snd_card *card = file->card; struct snd_kcontrol *kctl; - int idx, ret; + int idx; - down_write(&card->controls_rwsem); + guard(rwsem_write)(&card->controls_rwsem); kctl = snd_ctl_find_id_locked(card, id); - if (kctl == NULL) { - ret = -ENOENT; - goto error; - } - if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) { - ret = -EINVAL; - goto error; - } + if (kctl == NULL) + return -ENOENT; + if (!(kctl->vd[0].access & SNDRV_CTL_ELEM_ACCESS_USER)) + return -EINVAL; for (idx = 0; idx < kctl->count; idx++) - if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) { - ret = -EBUSY; - goto error; - } - ret = snd_ctl_remove_locked(card, kctl); -error: - up_write(&card->controls_rwsem); - return ret; + if (kctl->vd[idx].owner != NULL && kctl->vd[idx].owner != file) + return -EBUSY; + return snd_ctl_remove_locked(card, kctl); } /** @@ -764,18 +741,15 @@ int snd_ctl_rename_id(struct snd_card *card, struct snd_ctl_elem_id *src_id, struct snd_kcontrol *kctl; int saved_numid; - down_write(&card->controls_rwsem); + guard(rwsem_write)(&card->controls_rwsem); kctl = snd_ctl_find_id_locked(card, src_id); - if (kctl == NULL) { - up_write(&card->controls_rwsem); + if (kctl == NULL) return -ENOENT; - } saved_numid = kctl->id.numid; remove_hash_entries(card, kctl); kctl->id = *dst_id; kctl->id.numid = saved_numid; add_hash_entries(card, kctl); - up_write(&card->controls_rwsem); return 0; } EXPORT_SYMBOL(snd_ctl_rename_id); @@ -793,7 +767,7 @@ EXPORT_SYMBOL(snd_ctl_rename_id); void snd_ctl_rename(struct snd_card *card, struct snd_kcontrol *kctl, const char *name) { - down_write(&card->controls_rwsem); + guard(rwsem_write)(&card->controls_rwsem); remove_hash_entries(card, kctl); if (strscpy(kctl->id.name, name, sizeof(kctl->id.name)) < 0) @@ -801,7 +775,6 @@ void snd_ctl_rename(struct snd_card *card, struct snd_kcontrol *kctl, name, kctl->id.name); add_hash_entries(card, kctl); - up_write(&card->controls_rwsem); } EXPORT_SYMBOL(snd_ctl_rename); @@ -859,12 +832,8 @@ EXPORT_SYMBOL(snd_ctl_find_numid_locked); struct snd_kcontrol *snd_ctl_find_numid(struct snd_card *card, unsigned int numid) { - struct snd_kcontrol *kctl; - - down_read(&card->controls_rwsem); - kctl = snd_ctl_find_numid_locked(card, numid); - up_read(&card->controls_rwsem); - return kctl; + guard(rwsem_read)(&card->controls_rwsem); + return snd_ctl_find_numid_locked(card, numid); } EXPORT_SYMBOL(snd_ctl_find_numid); @@ -920,12 +889,8 @@ EXPORT_SYMBOL(snd_ctl_find_id_locked); struct snd_kcontrol *snd_ctl_find_id(struct snd_card *card, const struct snd_ctl_elem_id *id) { - struct snd_kcontrol *kctl; - - down_read(&card->controls_rwsem); - kctl = snd_ctl_find_id_locked(card, id); - up_read(&card->controls_rwsem); - return kctl; + guard(rwsem_read)(&card->controls_rwsem); + return snd_ctl_find_id_locked(card, id); } EXPORT_SYMBOL(snd_ctl_find_id); @@ -937,15 +902,15 @@ static int snd_ctl_card_info(struct snd_card *card, struct snd_ctl_file * ctl, info = kzalloc(sizeof(*info), GFP_KERNEL); if (! info) return -ENOMEM; - down_read(&snd_ioctl_rwsem); - info->card = card->number; - strscpy(info->id, card->id, sizeof(info->id)); - strscpy(info->driver, card->driver, sizeof(info->driver)); - strscpy(info->name, card->shortname, sizeof(info->name)); - strscpy(info->longname, card->longname, sizeof(info->longname)); - strscpy(info->mixername, card->mixername, sizeof(info->mixername)); - strscpy(info->components, card->components, sizeof(info->components)); - up_read(&snd_ioctl_rwsem); + scoped_guard(rwsem_read, &snd_ioctl_rwsem) { + info->card = card->number; + strscpy(info->id, card->id, sizeof(info->id)); + strscpy(info->driver, card->driver, sizeof(info->driver)); + strscpy(info->name, card->shortname, sizeof(info->name)); + strscpy(info->longname, card->longname, sizeof(info->longname)); + strscpy(info->mixername, card->mixername, sizeof(info->mixername)); + strscpy(info->components, card->components, sizeof(info->components)); + } if (copy_to_user(arg, info, sizeof(struct snd_ctl_card_info))) return -EFAULT; return 0; @@ -957,37 +922,31 @@ static int snd_ctl_elem_list(struct snd_card *card, struct snd_kcontrol *kctl; struct snd_ctl_elem_id id; unsigned int offset, space, jidx; - int err = 0; offset = list->offset; space = list->space; - down_read(&card->controls_rwsem); + guard(rwsem_read)(&card->controls_rwsem); list->count = card->controls_count; list->used = 0; - if (space > 0) { - list_for_each_entry(kctl, &card->controls, list) { - if (offset >= kctl->count) { - offset -= kctl->count; - continue; - } - for (jidx = offset; jidx < kctl->count; jidx++) { - snd_ctl_build_ioff(&id, kctl, jidx); - if (copy_to_user(list->pids + list->used, &id, - sizeof(id))) { - err = -EFAULT; - goto out; - } - list->used++; - if (!--space) - goto out; - } - offset = 0; + if (!space) + return 0; + list_for_each_entry(kctl, &card->controls, list) { + if (offset >= kctl->count) { + offset -= kctl->count; + continue; } + for (jidx = offset; jidx < kctl->count; jidx++) { + snd_ctl_build_ioff(&id, kctl, jidx); + if (copy_to_user(list->pids + list->used, &id, sizeof(id))) + return -EFAULT; + list->used++; + if (!--space) + return 0; + } + offset = 0; } - out: - up_read(&card->controls_rwsem); - return err; + return 0; } static int snd_ctl_elem_list_user(struct snd_card *card, @@ -1235,16 +1194,12 @@ static int snd_ctl_elem_info(struct snd_ctl_file *ctl, { struct snd_card *card = ctl->card; struct snd_kcontrol *kctl; - int result; - down_read(&card->controls_rwsem); + guard(rwsem_read)(&card->controls_rwsem); kctl = snd_ctl_find_id_locked(card, &info->id); - if (kctl == NULL) - result = -ENOENT; - else - result = __snd_ctl_elem_info(card, kctl, info, ctl); - up_read(&card->controls_rwsem); - return result; + if (!kctl) + return -ENOENT; + return __snd_ctl_elem_info(card, kctl, info, ctl); } static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl, @@ -1276,19 +1231,15 @@ static int snd_ctl_elem_read(struct snd_card *card, const u32 pattern = 0xdeadbeef; int ret; - down_read(&card->controls_rwsem); + guard(rwsem_read)(&card->controls_rwsem); kctl = snd_ctl_find_id_locked(card, &control->id); - if (kctl == NULL) { - ret = -ENOENT; - goto unlock; - } + if (!kctl) + return -ENOENT; index_offset = snd_ctl_get_ioff(kctl, &control->id); vd = &kctl->vd[index_offset]; - if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_READ) || kctl->get == NULL) { - ret = -EPERM; - goto unlock; - } + if (!(vd->access & SNDRV_CTL_ELEM_ACCESS_READ) || !kctl->get) + return -EPERM; snd_ctl_build_ioff(&control->id, kctl, index_offset); @@ -1298,7 +1249,7 @@ static int snd_ctl_elem_read(struct snd_card *card, info.id = control->id; ret = __snd_ctl_elem_info(card, kctl, &info, NULL); if (ret < 0) - goto unlock; + return ret; #endif if (!snd_ctl_skip_validation(&info)) @@ -1308,7 +1259,7 @@ static int snd_ctl_elem_read(struct snd_card *card, ret = kctl->get(kctl, control); snd_power_unref(card); if (ret < 0) - goto unlock; + return ret; if (!snd_ctl_skip_validation(&info) && sanity_check_elem_value(card, control, &info, pattern) < 0) { dev_err(card->dev, @@ -1316,12 +1267,9 @@ static int snd_ctl_elem_read(struct snd_card *card, control->id.iface, control->id.device, control->id.subdevice, control->id.name, control->id.index); - ret = -EINVAL; - goto unlock; + return -EINVAL; } -unlock: - up_read(&card->controls_rwsem); - return ret; + return 0; } static int snd_ctl_elem_read_user(struct snd_card *card, @@ -1426,25 +1374,18 @@ static int snd_ctl_elem_lock(struct snd_ctl_file *file, struct snd_ctl_elem_id id; struct snd_kcontrol *kctl; struct snd_kcontrol_volatile *vd; - int result; if (copy_from_user(&id, _id, sizeof(id))) return -EFAULT; - down_write(&card->controls_rwsem); + guard(rwsem_write)(&card->controls_rwsem); kctl = snd_ctl_find_id_locked(card, &id); - if (kctl == NULL) { - result = -ENOENT; - } else { - vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)]; - if (vd->owner != NULL) - result = -EBUSY; - else { - vd->owner = file; - result = 0; - } - } - up_write(&card->controls_rwsem); - return result; + if (!kctl) + return -ENOENT; + vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)]; + if (vd->owner) + return -EBUSY; + vd->owner = file; + return 0; } static int snd_ctl_elem_unlock(struct snd_ctl_file *file, @@ -1454,27 +1395,20 @@ static int snd_ctl_elem_unlock(struct snd_ctl_file *file, struct snd_ctl_elem_id id; struct snd_kcontrol *kctl; struct snd_kcontrol_volatile *vd; - int result; if (copy_from_user(&id, _id, sizeof(id))) return -EFAULT; - down_write(&card->controls_rwsem); + guard(rwsem_write)(&card->controls_rwsem); kctl = snd_ctl_find_id_locked(card, &id); - if (kctl == NULL) { - result = -ENOENT; - } else { - vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)]; - if (vd->owner == NULL) - result = -EINVAL; - else if (vd->owner != file) - result = -EPERM; - else { - vd->owner = NULL; - result = 0; - } - } - up_write(&card->controls_rwsem); - return result; + if (!kctl) + return -ENOENT; + vd = &kctl->vd[snd_ctl_get_ioff(kctl, &id)]; + if (!vd->owner) + return -EINVAL; + if (vd->owner != file) + return -EPERM; + vd->owner = NULL; + return 0; } struct user_element { @@ -1756,11 +1690,9 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file, private_size = value_sizes[info->type] * info->count; alloc_size = compute_user_elem_size(private_size, count); - down_write(&card->controls_rwsem); - if (check_user_elem_overflow(card, alloc_size)) { - err = -ENOMEM; - goto unlock; - } + guard(rwsem_write)(&card->controls_rwsem); + if (check_user_elem_overflow(card, alloc_size)) + return -ENOMEM; /* * Keep memory object for this userspace control. After passing this @@ -1770,13 +1702,12 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file, */ err = snd_ctl_new(&kctl, count, access, file); if (err < 0) - goto unlock; + return err; memcpy(&kctl->id, &info->id, sizeof(kctl->id)); ue = kzalloc(alloc_size, GFP_KERNEL); if (!ue) { kfree(kctl); - err = -ENOMEM; - goto unlock; + return -ENOMEM; } kctl->private_data = ue; kctl->private_free = snd_ctl_elem_user_free; @@ -1794,7 +1725,7 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file, err = snd_ctl_elem_init_enum_names(ue); if (err < 0) { snd_ctl_free_one(kctl); - goto unlock; + return err; } } @@ -1814,7 +1745,7 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file, err = __snd_ctl_add_replace(card, kctl, CTL_ADD_EXCLUSIVE); if (err < 0) { snd_ctl_free_one(kctl); - goto unlock; + return err; } offset = snd_ctl_get_ioff(kctl, &info->id); snd_ctl_build_ioff(&info->id, kctl, offset); @@ -1825,9 +1756,7 @@ static int snd_ctl_elem_add(struct snd_ctl_file *file, * applications because the field originally means PID of a process * which locks the element. */ - unlock: - up_write(&card->controls_rwsem); - return err; + return 0; } static int snd_ctl_elem_add_user(struct snd_ctl_file *file, @@ -2029,34 +1958,31 @@ static long snd_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg case SNDRV_CTL_IOCTL_SUBSCRIBE_EVENTS: return snd_ctl_subscribe_events(ctl, ip); case SNDRV_CTL_IOCTL_TLV_READ: - down_read(&ctl->card->controls_rwsem); - err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_READ); + scoped_guard(rwsem_read, &ctl->card->controls_rwsem) + err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_READ); up_read(&ctl->card->controls_rwsem); return err; case SNDRV_CTL_IOCTL_TLV_WRITE: - down_write(&ctl->card->controls_rwsem); - err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_WRITE); + scoped_guard(rwsem_write, &ctl->card->controls_rwsem) + err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_WRITE); up_write(&ctl->card->controls_rwsem); return err; case SNDRV_CTL_IOCTL_TLV_COMMAND: - down_write(&ctl->card->controls_rwsem); - err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_CMD); - up_write(&ctl->card->controls_rwsem); + scoped_guard(rwsem_write, &ctl->card->controls_rwsem) + err = snd_ctl_tlv_ioctl(ctl, argp, SNDRV_CTL_TLV_OP_CMD); return err; case SNDRV_CTL_IOCTL_POWER: return -ENOPROTOOPT; case SNDRV_CTL_IOCTL_POWER_STATE: return put_user(SNDRV_CTL_POWER_D0, ip) ? -EFAULT : 0; } - down_read(&snd_ioctl_rwsem); + + guard(rwsem_read)(&snd_ioctl_rwsem); list_for_each_entry(p, &snd_control_ioctls, list) { err = p->fioctl(card, ctl, cmd, arg); - if (err != -ENOIOCTLCMD) { - up_read(&snd_ioctl_rwsem); + if (err != -ENOIOCTLCMD) return err; - } } - up_read(&snd_ioctl_rwsem); dev_dbg(card->dev, "unknown ioctl = 0x%x\n", cmd); return -ENOTTY; } @@ -2148,9 +2074,8 @@ static int _snd_ctl_register_ioctl(snd_kctl_ioctl_func_t fcn, struct list_head * if (pn == NULL) return -ENOMEM; pn->fioctl = fcn; - down_write(&snd_ioctl_rwsem); + guard(rwsem_write)(&snd_ioctl_rwsem); list_add_tail(&pn->list, lists); - up_write(&snd_ioctl_rwsem); return 0; } @@ -2193,16 +2118,14 @@ static int _snd_ctl_unregister_ioctl(snd_kctl_ioctl_func_t fcn, if (snd_BUG_ON(!fcn)) return -EINVAL; - down_write(&snd_ioctl_rwsem); + guard(rwsem_write)(&snd_ioctl_rwsem); list_for_each_entry(p, lists, list) { if (p->fioctl == fcn) { list_del(&p->list); - up_write(&snd_ioctl_rwsem); kfree(p); return 0; } } - up_write(&snd_ioctl_rwsem); snd_BUG(); return -EINVAL; } @@ -2249,9 +2172,8 @@ int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type) { struct snd_ctl_file *kctl; int subdevice = -1; - unsigned long flags; - read_lock_irqsave(&card->ctl_files_rwlock, flags); + guard(read_lock_irqsave)(&card->ctl_files_rwlock); list_for_each_entry(kctl, &card->ctl_files, list) { if (kctl->pid == task_pid(current)) { subdevice = kctl->preferred_subdevice[type]; @@ -2259,7 +2181,6 @@ int snd_ctl_get_preferred_subdevice(struct snd_card *card, int type) break; } } - read_unlock_irqrestore(&card->ctl_files_rwlock, flags); return subdevice; } EXPORT_SYMBOL_GPL(snd_ctl_get_preferred_subdevice); @@ -2289,13 +2210,11 @@ int snd_ctl_request_layer(const char *module_name) if (module_name == NULL) return 0; - down_read(&snd_ctl_layer_rwsem); - for (lops = snd_ctl_layer; lops; lops = lops->next) - if (strcmp(lops->module_name, module_name) == 0) - break; - up_read(&snd_ctl_layer_rwsem); - if (lops) - return 0; + scoped_guard(rwsem_read, &snd_ctl_layer_rwsem) { + for (lops = snd_ctl_layer; lops; lops = lops->next) + if (strcmp(lops->module_name, module_name) == 0) + return 0; + } return request_module(module_name); } EXPORT_SYMBOL_GPL(snd_ctl_request_layer); @@ -2312,16 +2231,15 @@ void snd_ctl_register_layer(struct snd_ctl_layer_ops *lops) struct snd_card *card; int card_number; - down_write(&snd_ctl_layer_rwsem); - lops->next = snd_ctl_layer; - snd_ctl_layer = lops; - up_write(&snd_ctl_layer_rwsem); + scoped_guard(rwsem_write, &snd_ctl_layer_rwsem) { + lops->next = snd_ctl_layer; + snd_ctl_layer = lops; + } for (card_number = 0; card_number < SNDRV_CARDS; card_number++) { card = snd_card_ref(card_number); if (card) { - down_read(&card->controls_rwsem); - lops->lregister(card); - up_read(&card->controls_rwsem); + scoped_guard(rwsem_read, &card->controls_rwsem) + lops->lregister(card); snd_card_unref(card); } } @@ -2340,7 +2258,7 @@ void snd_ctl_disconnect_layer(struct snd_ctl_layer_ops *lops) { struct snd_ctl_layer_ops *lops2, *prev_lops2; - down_write(&snd_ctl_layer_rwsem); + guard(rwsem_write)(&snd_ctl_layer_rwsem); for (lops2 = snd_ctl_layer, prev_lops2 = NULL; lops2; lops2 = lops2->next) { if (lops2 == lops) { if (!prev_lops2) @@ -2351,7 +2269,6 @@ void snd_ctl_disconnect_layer(struct snd_ctl_layer_ops *lops) } prev_lops2 = lops2; } - up_write(&snd_ctl_layer_rwsem); } EXPORT_SYMBOL_GPL(snd_ctl_disconnect_layer); @@ -2372,25 +2289,29 @@ static const struct file_operations snd_ctl_f_ops = .fasync = snd_ctl_fasync, }; +/* call lops under rwsems; called from snd_ctl_dev_*() below() */ +#define call_snd_ctl_lops(_card, _op) \ + do { \ + struct snd_ctl_layer_ops *lops; \ + guard(rwsem_read)(&(_card)->controls_rwsem); \ + guard(rwsem_read)(&snd_ctl_layer_rwsem); \ + for (lops = snd_ctl_layer; lops; lops = lops->next) \ + lops->_op(_card); \ + } while (0) + /* * registration of the control device */ static int snd_ctl_dev_register(struct snd_device *device) { struct snd_card *card = device->device_data; - struct snd_ctl_layer_ops *lops; int err; err = snd_register_device(SNDRV_DEVICE_TYPE_CONTROL, card, -1, &snd_ctl_f_ops, card, card->ctl_dev); if (err < 0) return err; - down_read(&card->controls_rwsem); - down_read(&snd_ctl_layer_rwsem); - for (lops = snd_ctl_layer; lops; lops = lops->next) - lops->lregister(card); - up_read(&snd_ctl_layer_rwsem); - up_read(&card->controls_rwsem); + call_snd_ctl_lops(card, lregister); return 0; } @@ -2401,23 +2322,15 @@ static int snd_ctl_dev_disconnect(struct snd_device *device) { struct snd_card *card = device->device_data; struct snd_ctl_file *ctl; - struct snd_ctl_layer_ops *lops; - unsigned long flags; - read_lock_irqsave(&card->ctl_files_rwlock, flags); - list_for_each_entry(ctl, &card->ctl_files, list) { - wake_up(&ctl->change_sleep); - snd_kill_fasync(ctl->fasync, SIGIO, POLL_ERR); + scoped_guard(read_lock_irqsave, &card->ctl_files_rwlock) { + list_for_each_entry(ctl, &card->ctl_files, list) { + wake_up(&ctl->change_sleep); + snd_kill_fasync(ctl->fasync, SIGIO, POLL_ERR); + } } - read_unlock_irqrestore(&card->ctl_files_rwlock, flags); - - down_read(&card->controls_rwsem); - down_read(&snd_ctl_layer_rwsem); - for (lops = snd_ctl_layer; lops; lops = lops->next) - lops->ldisconnect(card); - up_read(&snd_ctl_layer_rwsem); - up_read(&card->controls_rwsem); + call_snd_ctl_lops(card, ldisconnect); return snd_unregister_device(card->ctl_dev); } @@ -2429,17 +2342,17 @@ static int snd_ctl_dev_free(struct snd_device *device) struct snd_card *card = device->device_data; struct snd_kcontrol *control; - down_write(&card->controls_rwsem); - while (!list_empty(&card->controls)) { - control = snd_kcontrol(card->controls.next); - __snd_ctl_remove(card, control, false); - } + scoped_guard(rwsem_write, &card->controls_rwsem) { + while (!list_empty(&card->controls)) { + control = snd_kcontrol(card->controls.next); + __snd_ctl_remove(card, control, false); + } #ifdef CONFIG_SND_CTL_FAST_LOOKUP - xa_destroy(&card->ctl_numids); - xa_destroy(&card->ctl_hash); + xa_destroy(&card->ctl_numids); + xa_destroy(&card->ctl_hash); #endif - up_write(&card->controls_rwsem); + } put_device(card->ctl_dev); return 0; }