// SPDX-License-Identifier: GPL-2.0-or-later/* * Initialization routines * Copyright (c) by Jaroslav Kysela <perex@perex.cz> */ #include <linux/init.h>#include <linux/sched.h>#include <linux/module.h>#include <linux/device.h>#include <linux/file.h>#include <linux/slab.h>#include <linux/time.h>#include <linux/ctype.h>#include <linux/pm.h>#include <linux/debugfs.h>#include <linux/completion.h>#include <linux/interrupt.h> #include <sound/core.h>#include <sound/control.h>#include <sound/info.h> /* monitor files for graceful shutdown (hotplug) */struct snd_monitor_file { struct file *file; const struct file_operations *disconnected_f_op; struct list_head shutdown_list; /* still need to shutdown */ struct list_head list; /* link of monitor files */}; static DEFINE_SPINLOCK(shutdown_lock);static LIST_HEAD(shutdown_files); static const struct file_operations snd_shutdown_f_ops; /* locked for registering/using */static DECLARE_BITMAP(snd_cards_lock, SNDRV_CARDS);static struct snd_card *snd_cards[SNDRV_CARDS]; static DEFINE_MUTEX(snd_card_mutex); static char *slots[SNDRV_CARDS];module_param_array(slots, charp, NULL, 0444);MODULE_PARM_DESC(slots, "Module names assigned to the slots."); /* return non-zero if the given index is reserved for the given * module via slots option */static int module_slot_match(struct module *module, int idx){ int match = 1;#ifdef CONFIG_MODULES const char *s1, *s2; if (!module || !*module->name || !slots[idx]) return 0; s1 = module->name; s2 = slots[idx]; if (*s2 == '!') { match = 0; /* negative match */ s2++; } /* compare module name strings * hyphens are handled as equivalent with underscore */ for (;;) { char c1 = *s1++; char c2 = *s2++; if (c1 == '-') c1 = '_'; if (c2 == '-') c2 = '_'; if (c1 != c2) return !match; if (!c1) break; }#endif /* CONFIG_MODULES */ return match;} #if IS_ENABLED(CONFIG_SND_MIXER_OSS)int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag);EXPORT_SYMBOL(snd_mixer_oss_notify_callback);#endif static int check_empty_slot(struct module *module, int slot){ return !slots[slot] || !*slots[slot];} /* return an empty slot number (>= 0) found in the given bitmask @mask. * @mask == -1 == 0xffffffff means: take any free slot up to 32 * when no slot is available, return the original @mask as is. */static int get_slot_from_bitmask(int mask, int (*check)(struct module *, int), struct module *module){ int slot; for (slot = 0; slot < SNDRV_CARDS; slot++) { if (slot < 32 && !(mask & (1U << slot))) continue; if (!test_bit(slot, snd_cards_lock)) { if (check(module, slot)) return slot; /* found */ } } return mask; /* unchanged */} /* the default release callback set in snd_device_alloc() */static void default_release_alloc(struct device *dev){ kfree(dev);} /** * snd_device_alloc - Allocate and initialize struct device for sound devices * @dev_p: pointer to store the allocated device * @card: card to assign, optional * * For releasing the allocated device, call put_device(). */int snd_device_alloc(struct device **dev_p, struct snd_card *card){ struct device *dev; *dev_p = NULL; dev = kzalloc_obj(*dev); if (!dev) return -ENOMEM; device_initialize(dev); if (card) dev->parent = &card->card_dev; dev->class = &sound_class; dev->release = default_release_alloc; *dev_p = dev; return 0;}EXPORT_SYMBOL_GPL(snd_device_alloc); static int snd_card_init(struct snd_card *card, struct device *parent, int idx, const char *xid, struct module *module, size_t extra_size);static int snd_card_do_free(struct snd_card *card);static const struct attribute_group card_dev_attr_group; static void release_card_device(struct device *dev){ snd_card_do_free(dev_to_snd_card(dev));} /** * snd_card_new - create and initialize a soundcard structure * @parent: the parent device object * @idx: card index (address) [0 ... (SNDRV_CARDS-1)] * @xid: card identification (ASCII string) * @module: top level module for locking * @extra_size: allocate this extra size after the main soundcard structure * @card_ret: the pointer to store the created card instance * * The function allocates snd_card instance via kzalloc with the given * space for the driver to use freely. The allocated struct is stored * in the given card_ret pointer. * * Return: Zero if successful or a negative error code. */int snd_card_new(struct device *parent, int idx, const char *xid, struct module *module, int extra_size, struct snd_card **card_ret){ struct snd_card *card; int err; if (snd_BUG_ON(!card_ret)) return -EINVAL; *card_ret = NULL; if (extra_size < 0) extra_size = 0; card = kzalloc_flex(*card, private_data_area, extra_size); if (!card) return -ENOMEM; err = snd_card_init(card, parent, idx, xid, module, extra_size); if (err < 0) return err; /* card is freed by error handler */ *card_ret = card; return 0;}EXPORT_SYMBOL(snd_card_new); static void __snd_card_release(struct device *dev, void *data){ snd_card_free(data);} /** * snd_devm_card_new - managed snd_card object creation * @parent: the parent device object * @idx: card index (address) [0 ... (SNDRV_CARDS-1)] * @xid: card identification (ASCII string) * @module: top level module for locking * @extra_size: allocate this extra size after the main soundcard structure * @card_ret: the pointer to store the created card instance * * This function works like snd_card_new() but manages the allocated resource * via devres, i.e. you don't need to free explicitly. * * When a snd_card object is created with this function and registered via * snd_card_register(), the very first devres action to call snd_card_free() * is added automatically. In that way, the resource disconnection is assured * at first, then released in the expected order. * * If an error happens at the probe before snd_card_register() is called and * there have been other devres resources, you'd need to free the card manually * via snd_card_free() call in the error; otherwise it may lead to UAF due to * devres call orders. You can use snd_card_free_on_error() helper for * handling it more easily. * * Return: zero if successful, or a negative error code */int snd_devm_card_new(struct device *parent, int idx, const char *xid, struct module *module, size_t extra_size, struct snd_card **card_ret){ struct snd_card *card; int err; *card_ret = NULL; card = devres_alloc(__snd_card_release, struct_size(card, private_data_area, extra_size), GFP_KERNEL); if (!card) return -ENOMEM; card->managed = true; err = snd_card_init(card, parent, idx, xid, module, extra_size); if (err < 0) { devres_free(card); /* in managed mode, we need to free manually */ return err; } devres_add(parent, card); *card_ret = card; return 0;}EXPORT_SYMBOL_GPL(snd_devm_card_new); /** * snd_card_free_on_error - a small helper for handling devm probe errors * @dev: the managed device object * @ret: the return code from the probe callback * * This function handles the explicit snd_card_free() call at the error from * the probe callback. It's just a small helper for simplifying the error * handling with the managed devices. * * Return: zero if successful, or a negative error code */int snd_card_free_on_error(struct device *dev, int ret){ struct snd_card *card; if (!ret) return 0; card = devres_find(dev, __snd_card_release, NULL, NULL); if (card) snd_card_free(card); return ret;}EXPORT_SYMBOL_GPL(snd_card_free_on_error); static int snd_card_init(struct snd_card *card, struct device *parent, int idx, const char *xid, struct module *module, size_t extra_size){ int err; if (extra_size > 0) card->private_data = card->private_data_area; if (xid) strscpy(card->id, xid, sizeof(card->id)); err = 0; scoped_guard(mutex, &snd_card_mutex) { if (idx < 0) /* first check the matching module-name slot */ idx = get_slot_from_bitmask(idx, module_slot_match, module); if (idx < 0) /* if not matched, assign an empty slot */ idx = get_slot_from_bitmask(idx, check_empty_slot, module); if (idx < 0) err = -ENODEV; else if (idx < snd_ecards_limit) { if (test_bit(idx, snd_cards_lock)) err = -EBUSY; /* invalid */ } else if (idx >= SNDRV_CARDS) err = -ENODEV; if (!err) { set_bit(idx, snd_cards_lock); /* lock it */ if (idx >= snd_ecards_limit) snd_ecards_limit = idx + 1; /* increase the limit */ } } if (err < 0) { dev_err(parent, "cannot find the slot for index %d (range 0-%i), error: %d\n", idx, snd_ecards_limit - 1, err); if (!card->managed) kfree(card); /* manually free here, as no destructor called */ return err; } card->dev = parent; card->number = idx; WARN_ON(IS_MODULE(CONFIG_SND) && !module); card->module = module; INIT_LIST_HEAD(&card->devices); init_rwsem(&card->controls_rwsem); rwlock_init(&card->controls_rwlock); INIT_LIST_HEAD(&card->controls); INIT_LIST_HEAD(&card->ctl_files);#ifdef CONFIG_SND_CTL_FAST_LOOKUP xa_init(&card->ctl_numids); xa_init(&card->ctl_hash);#endif spin_lock_init(&card->files_lock); INIT_LIST_HEAD(&card->files_list); mutex_init(&card->memory_mutex);#ifdef CONFIG_PM init_waitqueue_head(&card->power_sleep); snd_refcount_init(&card->power_ref);#endif init_waitqueue_head(&card->remove_sleep); card->sync_irq = -1; device_initialize(&card->card_dev); card->card_dev.parent = parent; card->card_dev.class = &sound_class; card->card_dev.release = release_card_device; card->card_dev.groups = card->dev_groups; card->dev_groups[0] = &card_dev_attr_group; err = kobject_set_name(&card->card_dev.kobj, "card%d", idx); if (err < 0) goto __error; snprintf(card->irq_descr, sizeof(card->irq_descr), "%s:%s", dev_driver_string(card->dev), dev_name(&card->card_dev)); /* the control interface cannot be accessed from the user space until */ /* snd_cards_bitmask and snd_cards are set with snd_card_register */ err = snd_ctl_create(card); if (err < 0) { dev_err(parent, "unable to register control minors\n"); goto __error; } err = snd_info_card_create(card); if (err < 0) { dev_err(parent, "unable to create card info\n"); goto __error_ctl; } #ifdef CONFIG_SND_DEBUG card->debugfs_root = debugfs_create_dir(dev_name(&card->card_dev), sound_debugfs_root);#endif#ifdef CONFIG_SND_CTL_DEBUG card->value_buf = kmalloc_obj(*card->value_buf); if (!card->value_buf) return -ENOMEM;#endif return 0; __error_ctl: snd_device_free_all(card); __error: put_device(&card->card_dev); return err;} /** * snd_card_ref - Get the card object from the index * @idx: the card index * * Returns a card object corresponding to the given index or NULL if not found. * Release the object via snd_card_unref(). * * Return: a card object or NULL */struct snd_card *snd_card_ref(int idx){ struct snd_card *card; guard(mutex)(&snd_card_mutex); card = snd_cards[idx]; if (card) get_device(&card->card_dev); return card;}EXPORT_SYMBOL_GPL(snd_card_ref); /* return non-zero if a card is already locked */int snd_card_locked(int card){ guard(mutex)(&snd_card_mutex); return test_bit(card, snd_cards_lock);} static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig){ return -ENODEV;} static ssize_t snd_disconnect_read(struct file *file, char __user *buf, size_t count, loff_t *offset){ return -ENODEV;} static ssize_t snd_disconnect_write(struct file *file, const char __user *buf, size_t count, loff_t *offset){ return -ENODEV;} static int snd_disconnect_release(struct inode *inode, struct file *file){ struct snd_monitor_file *df = NULL, *_df; scoped_guard(spinlock, &shutdown_lock) { list_for_each_entry(_df, &shutdown_files, shutdown_list) { if (_df->file == file) { df = _df; list_del_init(&df->shutdown_list); break; } } } if (likely(df)) { if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync) df->disconnected_f_op->fasync(-1, file, 0); return df->disconnected_f_op->release(inode, file); } panic("%s(%p, %p) failed!", __func__, inode, file);} static __poll_t snd_disconnect_poll(struct file * file, poll_table * wait){ return EPOLLERR | EPOLLNVAL;} static long snd_disconnect_ioctl(struct file *file, unsigned int cmd, unsigned long arg){ return -ENODEV;} static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma){ return -ENODEV;} static int snd_disconnect_fasync(int fd, struct file *file, int on){ return -ENODEV;} static const struct file_operations snd_shutdown_f_ops = { .owner = THIS_MODULE, .llseek = snd_disconnect_llseek, .read = snd_disconnect_read, .write = snd_disconnect_write, .release = snd_disconnect_release, .poll = snd_disconnect_poll, .unlocked_ioctl = snd_disconnect_ioctl,#ifdef CONFIG_COMPAT .compat_ioctl = snd_disconnect_ioctl,#endif .mmap = snd_disconnect_mmap, .fasync = snd_disconnect_fasync}; /** * snd_card_disconnect - disconnect all APIs from the file-operations (user space) * @card: soundcard structure * * Disconnects all APIs from the file-operations (user space). * * Return: Zero, otherwise a negative error code. * * Note: The current implementation replaces all active file->f_op with special * dummy file operations (they do nothing except release). */void snd_card_disconnect(struct snd_card *card){ struct snd_monitor_file *mfile; if (!card) return;Lines 1–500 of 1208. 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// SPDX-License-Identifier: GPL-2.0-or-later /* * Initialization routines * Copyright (c) by Jaroslav Kysela <perex@perex.cz> */ #include <linux/init.h> #include <linux/sched.h> #include <linux/module.h> #include <linux/device.h> #include <linux/file.h> #include <linux/slab.h> #include <linux/time.h> #include <linux/ctype.h> #include <linux/pm.h> #include <linux/debugfs.h> #include <linux/completion.h> #include <linux/interrupt.h> #include <sound/core.h> #include <sound/control.h> #include <sound/info.h> /* monitor files for graceful shutdown (hotplug) */ struct snd_monitor_file { struct file *file; const struct file_operations *disconnected_f_op; struct list_head shutdown_list; /* still need to shutdown */ struct list_head list; /* link of monitor files */ }; static DEFINE_SPINLOCK(shutdown_lock); static LIST_HEAD(shutdown_files); static const struct file_operations snd_shutdown_f_ops; /* locked for registering/using */ static DECLARE_BITMAP(snd_cards_lock, SNDRV_CARDS); static struct snd_card *snd_cards[SNDRV_CARDS]; static DEFINE_MUTEX(snd_card_mutex); static char *slots[SNDRV_CARDS]; module_param_array(slots, charp, NULL, 0444); MODULE_PARM_DESC(slots, "Module names assigned to the slots."); /* return non-zero if the given index is reserved for the given * module via slots option */ static int module_slot_match(struct module *module, int idx) { int match = 1; #ifdef CONFIG_MODULES const char *s1, *s2; if (!module || !*module->name || !slots[idx]) return 0; s1 = module->name; s2 = slots[idx]; if (*s2 == '!') { match = 0; /* negative match */ s2++; } /* compare module name strings * hyphens are handled as equivalent with underscore */ for (;;) { char c1 = *s1++; char c2 = *s2++; if (c1 == '-') c1 = '_'; if (c2 == '-') c2 = '_'; if (c1 != c2) return !match; if (!c1) break; } #endif /* CONFIG_MODULES */ return match; } #if IS_ENABLED(CONFIG_SND_MIXER_OSS) int (*snd_mixer_oss_notify_callback)(struct snd_card *card, int free_flag); EXPORT_SYMBOL(snd_mixer_oss_notify_callback); #endif static int check_empty_slot(struct module *module, int slot) { return !slots[slot] || !*slots[slot]; } /* return an empty slot number (>= 0) found in the given bitmask @mask. * @mask == -1 == 0xffffffff means: take any free slot up to 32 * when no slot is available, return the original @mask as is. */ static int get_slot_from_bitmask(int mask, int (*check)(struct module *, int), struct module *module) { int slot; for (slot = 0; slot < SNDRV_CARDS; slot++) { if (slot < 32 && !(mask & (1U << slot))) continue; if (!test_bit(slot, snd_cards_lock)) { if (check(module, slot)) return slot; /* found */ } } return mask; /* unchanged */ } /* the default release callback set in snd_device_alloc() */ static void default_release_alloc(struct device *dev) { kfree(dev); } /** * snd_device_alloc - Allocate and initialize struct device for sound devices * @dev_p: pointer to store the allocated device * @card: card to assign, optional * * For releasing the allocated device, call put_device(). */ int snd_device_alloc(struct device **dev_p, struct snd_card *card) { struct device *dev; *dev_p = NULL; dev = kzalloc_obj(*dev); if (!dev) return -ENOMEM; device_initialize(dev); if (card) dev->parent = &card->card_dev; dev->class = &sound_class; dev->release = default_release_alloc; *dev_p = dev; return 0; } EXPORT_SYMBOL_GPL(snd_device_alloc); static int snd_card_init(struct snd_card *card, struct device *parent, int idx, const char *xid, struct module *module, size_t extra_size); static int snd_card_do_free(struct snd_card *card); static const struct attribute_group card_dev_attr_group; static void release_card_device(struct device *dev) { snd_card_do_free(dev_to_snd_card(dev)); } /** * snd_card_new - create and initialize a soundcard structure * @parent: the parent device object * @idx: card index (address) [0 ... (SNDRV_CARDS-1)] * @xid: card identification (ASCII string) * @module: top level module for locking * @extra_size: allocate this extra size after the main soundcard structure * @card_ret: the pointer to store the created card instance * * The function allocates snd_card instance via kzalloc with the given * space for the driver to use freely. The allocated struct is stored * in the given card_ret pointer. * * Return: Zero if successful or a negative error code. */ int snd_card_new(struct device *parent, int idx, const char *xid, struct module *module, int extra_size, struct snd_card **card_ret) { struct snd_card *card; int err; if (snd_BUG_ON(!card_ret)) return -EINVAL; *card_ret = NULL; if (extra_size < 0) extra_size = 0; card = kzalloc_flex(*card, private_data_area, extra_size); if (!card) return -ENOMEM; err = snd_card_init(card, parent, idx, xid, module, extra_size); if (err < 0) return err; /* card is freed by error handler */ *card_ret = card; return 0; } EXPORT_SYMBOL(snd_card_new); static void __snd_card_release(struct device *dev, void *data) { snd_card_free(data); } /** * snd_devm_card_new - managed snd_card object creation * @parent: the parent device object * @idx: card index (address) [0 ... (SNDRV_CARDS-1)] * @xid: card identification (ASCII string) * @module: top level module for locking * @extra_size: allocate this extra size after the main soundcard structure * @card_ret: the pointer to store the created card instance * * This function works like snd_card_new() but manages the allocated resource * via devres, i.e. you don't need to free explicitly. * * When a snd_card object is created with this function and registered via * snd_card_register(), the very first devres action to call snd_card_free() * is added automatically. In that way, the resource disconnection is assured * at first, then released in the expected order. * * If an error happens at the probe before snd_card_register() is called and * there have been other devres resources, you'd need to free the card manually * via snd_card_free() call in the error; otherwise it may lead to UAF due to * devres call orders. You can use snd_card_free_on_error() helper for * handling it more easily. * * Return: zero if successful, or a negative error code */ int snd_devm_card_new(struct device *parent, int idx, const char *xid, struct module *module, size_t extra_size, struct snd_card **card_ret) { struct snd_card *card; int err; *card_ret = NULL; card = devres_alloc(__snd_card_release, struct_size(card, private_data_area, extra_size), GFP_KERNEL); if (!card) return -ENOMEM; card->managed = true; err = snd_card_init(card, parent, idx, xid, module, extra_size); if (err < 0) { devres_free(card); /* in managed mode, we need to free manually */ return err; } devres_add(parent, card); *card_ret = card; return 0; } EXPORT_SYMBOL_GPL(snd_devm_card_new); /** * snd_card_free_on_error - a small helper for handling devm probe errors * @dev: the managed device object * @ret: the return code from the probe callback * * This function handles the explicit snd_card_free() call at the error from * the probe callback. It's just a small helper for simplifying the error * handling with the managed devices. * * Return: zero if successful, or a negative error code */ int snd_card_free_on_error(struct device *dev, int ret) { struct snd_card *card; if (!ret) return 0; card = devres_find(dev, __snd_card_release, NULL, NULL); if (card) snd_card_free(card); return ret; } EXPORT_SYMBOL_GPL(snd_card_free_on_error); static int snd_card_init(struct snd_card *card, struct device *parent, int idx, const char *xid, struct module *module, size_t extra_size) { int err; if (extra_size > 0) card->private_data = card->private_data_area; if (xid) strscpy(card->id, xid, sizeof(card->id)); err = 0; scoped_guard(mutex, &snd_card_mutex) { if (idx < 0) /* first check the matching module-name slot */ idx = get_slot_from_bitmask(idx, module_slot_match, module); if (idx < 0) /* if not matched, assign an empty slot */ idx = get_slot_from_bitmask(idx, check_empty_slot, module); if (idx < 0) err = -ENODEV; else if (idx < snd_ecards_limit) { if (test_bit(idx, snd_cards_lock)) err = -EBUSY; /* invalid */ } else if (idx >= SNDRV_CARDS) err = -ENODEV; if (!err) { set_bit(idx, snd_cards_lock); /* lock it */ if (idx >= snd_ecards_limit) snd_ecards_limit = idx + 1; /* increase the limit */ } } if (err < 0) { dev_err(parent, "cannot find the slot for index %d (range 0-%i), error: %d\n", idx, snd_ecards_limit - 1, err); if (!card->managed) kfree(card); /* manually free here, as no destructor called */ return err; } card->dev = parent; card->number = idx; WARN_ON(IS_MODULE(CONFIG_SND) && !module); card->module = module; INIT_LIST_HEAD(&card->devices); init_rwsem(&card->controls_rwsem); rwlock_init(&card->controls_rwlock); INIT_LIST_HEAD(&card->controls); INIT_LIST_HEAD(&card->ctl_files); #ifdef CONFIG_SND_CTL_FAST_LOOKUP xa_init(&card->ctl_numids); xa_init(&card->ctl_hash); #endif spin_lock_init(&card->files_lock); INIT_LIST_HEAD(&card->files_list); mutex_init(&card->memory_mutex); #ifdef CONFIG_PM init_waitqueue_head(&card->power_sleep); snd_refcount_init(&card->power_ref); #endif init_waitqueue_head(&card->remove_sleep); card->sync_irq = -1; device_initialize(&card->card_dev); card->card_dev.parent = parent; card->card_dev.class = &sound_class; card->card_dev.release = release_card_device; card->card_dev.groups = card->dev_groups; card->dev_groups[0] = &card_dev_attr_group; err = kobject_set_name(&card->card_dev.kobj, "card%d", idx); if (err < 0) goto __error; snprintf(card->irq_descr, sizeof(card->irq_descr), "%s:%s", dev_driver_string(card->dev), dev_name(&card->card_dev)); /* the control interface cannot be accessed from the user space until */ /* snd_cards_bitmask and snd_cards are set with snd_card_register */ err = snd_ctl_create(card); if (err < 0) { dev_err(parent, "unable to register control minors\n"); goto __error; } err = snd_info_card_create(card); if (err < 0) { dev_err(parent, "unable to create card info\n"); goto __error_ctl; } #ifdef CONFIG_SND_DEBUG card->debugfs_root = debugfs_create_dir(dev_name(&card->card_dev), sound_debugfs_root); #endif #ifdef CONFIG_SND_CTL_DEBUG card->value_buf = kmalloc_obj(*card->value_buf); if (!card->value_buf) return -ENOMEM; #endif return 0; __error_ctl: snd_device_free_all(card); __error: put_device(&card->card_dev); return err; } /** * snd_card_ref - Get the card object from the index * @idx: the card index * * Returns a card object corresponding to the given index or NULL if not found. * Release the object via snd_card_unref(). * * Return: a card object or NULL */ struct snd_card *snd_card_ref(int idx) { struct snd_card *card; guard(mutex)(&snd_card_mutex); card = snd_cards[idx]; if (card) get_device(&card->card_dev); return card; } EXPORT_SYMBOL_GPL(snd_card_ref); /* return non-zero if a card is already locked */ int snd_card_locked(int card) { guard(mutex)(&snd_card_mutex); return test_bit(card, snd_cards_lock); } static loff_t snd_disconnect_llseek(struct file *file, loff_t offset, int orig) { return -ENODEV; } static ssize_t snd_disconnect_read(struct file *file, char __user *buf, size_t count, loff_t *offset) { return -ENODEV; } static ssize_t snd_disconnect_write(struct file *file, const char __user *buf, size_t count, loff_t *offset) { return -ENODEV; } static int snd_disconnect_release(struct inode *inode, struct file *file) { struct snd_monitor_file *df = NULL, *_df; scoped_guard(spinlock, &shutdown_lock) { list_for_each_entry(_df, &shutdown_files, shutdown_list) { if (_df->file == file) { df = _df; list_del_init(&df->shutdown_list); break; } } } if (likely(df)) { if ((file->f_flags & FASYNC) && df->disconnected_f_op->fasync) df->disconnected_f_op->fasync(-1, file, 0); return df->disconnected_f_op->release(inode, file); } panic("%s(%p, %p) failed!", __func__, inode, file); } static __poll_t snd_disconnect_poll(struct file * file, poll_table * wait) { return EPOLLERR | EPOLLNVAL; } static long snd_disconnect_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { return -ENODEV; } static int snd_disconnect_mmap(struct file *file, struct vm_area_struct *vma) { return -ENODEV; } static int snd_disconnect_fasync(int fd, struct file *file, int on) { return -ENODEV; } static const struct file_operations snd_shutdown_f_ops = { .owner = THIS_MODULE, .llseek = snd_disconnect_llseek, .read = snd_disconnect_read, .write = snd_disconnect_write, .release = snd_disconnect_release, .poll = snd_disconnect_poll, .unlocked_ioctl = snd_disconnect_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = snd_disconnect_ioctl, #endif .mmap = snd_disconnect_mmap, .fasync = snd_disconnect_fasync }; /** * snd_card_disconnect - disconnect all APIs from the file-operations (user space) * @card: soundcard structure * * Disconnects all APIs from the file-operations (user space). * * Return: Zero, otherwise a negative error code. * * Note: The current implementation replaces all active file->f_op with special * dummy file operations (they do nothing except release). */ void snd_card_disconnect(struct snd_card *card) { struct snd_monitor_file *mfile; if (!card) return;