From 721da5cee9d43901105f5b8bd33fcb9101b12fc3 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Thu, 23 Feb 2023 08:33:26 +0100 Subject: driver core: remove CONFIG_SYSFS_DEPRECATED and CONFIG_SYSFS_DEPRECATED_V2 CONFIG_SYSFS_DEPRECATED was added in commit 88a22c985e35 ("CONFIG_SYSFS_DEPRECATED") in 2006 to allow systems with older versions of some tools (i.e. Fedora 3's version of udev) to boot properly. Four years later, in 2010, the option was attempted to be removed as most of userspace should have been fixed up properly by then, but some kernel developers clung to those old systems and refused to update, so we added CONFIG_SYSFS_DEPRECATED_V2 in commit e52eec13cd6b ("SYSFS: Allow boot time switching between deprecated and modern sysfs layout") to allow them to continue to boot properly, and we allowed a boot time parameter to be used to switch back to the old format if needed. Over time, the logic that was covered under these config options was slowly removed from individual driver subsystems successfully, removed, and the only thing that is now left in the kernel are some changes in the block layer's representation in sysfs where real directories are used instead of symlinks like normal. Because the original changes were done to userspace tools in 2006, and all distros that use those tools are long end-of-life, and older non-udev-based systems do not care about the block layer's sysfs representation, it is time to finally remove this old logic and the config entries from the kernel. Cc: Jonathan Corbet Cc: "Rafael J. Wysocki" Cc: linux-block@vger.kernel.org Cc: linux-doc@vger.kernel.org Acked-by: Jens Axboe Link: https://lore.kernel.org/r/20230223073326.2073220-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index 2373b3e210d89..fb8f2a1e1c198 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -180,7 +180,7 @@ int __class_register(struct class *cls, struct lock_class_key *key) #if defined(CONFIG_BLOCK) /* let the block class directory show up in the root of sysfs */ - if (!sysfs_deprecated || cls != &block_class) + if (cls != &block_class) cp->subsys.kobj.kset = class_kset; #else cp->subsys.kobj.kset = class_kset; -- cgit v1.2.3 From 22fd6153c16a40d123d8c9936967d0a59e417129 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Tue, 7 Mar 2023 08:51:02 +0100 Subject: driver core: class: fix block class problem when removing CONFIG_SYSFS_DEPRECATED* In removing the CONFIG_SYSFS_DEPRECATED and CONFIG_SYSFS_DEPRECATED_V2 config options, I messed up in the __class_register() function and got the logic incorrect. Fix this all up by just removing the special case of a block device class logic in this function, as that is what is intended. In testing, this solves the boot problem on my systems, hopefully on others as well. Cc: "Rafael J. Wysocki" Reported-by: Stephen Rothwell Fixes: 721da5cee9d4 ("driver core: remove CONFIG_SYSFS_DEPRECATED and CONFIG_SYSFS_DEPRECATED_V2") Link: https://lore.kernel.org/r/20230307075102.3537-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 6 ------ 1 file changed, 6 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index fb8f2a1e1c198..5983eead8391f 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -178,13 +178,7 @@ int __class_register(struct class *cls, struct lock_class_key *key) if (!cls->dev_kobj) cls->dev_kobj = sysfs_dev_char_kobj; -#if defined(CONFIG_BLOCK) - /* let the block class directory show up in the root of sysfs */ - if (cls != &block_class) - cp->subsys.kobj.kset = class_kset; -#else cp->subsys.kobj.kset = class_kset; -#endif cp->subsys.kobj.ktype = &class_ktype; cp->class = cls; cls->p = cp; -- cgit v1.2.3 From 4a46ac9d64030d9f6f18baaf115a3558880c1ae2 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 13 Mar 2023 19:18:32 +0100 Subject: driver core: class: specify the module owner in __class_register() There's no need to manually have to set the module owner of a class, the compiler should do it automatically for you, so add a module * to the __class_register() function and allow it to set the module owner automatically. This will let us move the module pointer out of struct class eventually, as it should not be embedded in there if we wish for it to be a read-only structure eventually. And, funny story, this module pointer isn't even being used for anything, so while we will keep it around for now, it's not like it even matters. Cc: "Rafael J. Wysocki" Link: https://lore.kernel.org/r/20230313181843.1207845-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 6 +++--- include/linux/device/class.h | 9 +++++---- 2 files changed, 8 insertions(+), 7 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index 5983eead8391f..90dc5788957af 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -154,7 +154,7 @@ static void class_remove_groups(struct class *cls, return sysfs_remove_groups(&cls->p->subsys.kobj, groups); } -int __class_register(struct class *cls, struct lock_class_key *key) +int __class_register(struct class *cls, struct module *owner, struct lock_class_key *key) { struct subsys_private *cp; int error; @@ -187,6 +187,7 @@ int __class_register(struct class *cls, struct lock_class_key *key) if (error) goto err_out; + cls->owner = owner; error = class_add_groups(class_get(cls), cls->class_groups); class_put(cls); if (error) { @@ -244,10 +245,9 @@ struct class *__class_create(struct module *owner, const char *name, } cls->name = name; - cls->owner = owner; cls->class_release = class_create_release; - retval = __class_register(cls, key); + retval = __class_register(cls, owner, key); if (retval) goto error; diff --git a/include/linux/device/class.h b/include/linux/device/class.h index 42cc3fb44a846..d1ba4ee235dc3 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -85,15 +85,16 @@ struct class_dev_iter { extern struct kobject *sysfs_dev_block_kobj; extern struct kobject *sysfs_dev_char_kobj; extern int __must_check __class_register(struct class *class, + struct module *owner, struct lock_class_key *key); extern void class_unregister(struct class *class); /* This is a #define to keep the compiler from merging different * instances of the __key variable */ -#define class_register(class) \ -({ \ - static struct lock_class_key __key; \ - __class_register(class, &__key); \ +#define class_register(class) \ +({ \ + static struct lock_class_key __key; \ + __class_register(class, THIS_MODULE, &__key); \ }) struct class_compat; -- cgit v1.2.3 From 6e30a66433afee90e902ced95d7136e8f7edcc7e Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 13 Mar 2023 19:18:34 +0100 Subject: driver core: class: remove struct module owner out of struct class The module owner field for a struct class was never actually used, so remove it as it is not doing anything at all. Cc: "Rafael J. Wysocki" Link: https://lore.kernel.org/r/20230313181843.1207845-3-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 9 +++------ include/linux/device/class.h | 18 +++++++----------- 2 files changed, 10 insertions(+), 17 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index 90dc5788957af..9439c6c7466fb 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -154,7 +154,7 @@ static void class_remove_groups(struct class *cls, return sysfs_remove_groups(&cls->p->subsys.kobj, groups); } -int __class_register(struct class *cls, struct module *owner, struct lock_class_key *key) +int __class_register(struct class *cls, struct lock_class_key *key) { struct subsys_private *cp; int error; @@ -187,7 +187,6 @@ int __class_register(struct class *cls, struct module *owner, struct lock_class_ if (error) goto err_out; - cls->owner = owner; error = class_add_groups(class_get(cls), cls->class_groups); class_put(cls); if (error) { @@ -220,7 +219,6 @@ static void class_create_release(struct class *cls) /** * __class_create - create a struct class structure - * @owner: pointer to the module that is to "own" this struct class * @name: pointer to a string for the name of this class. * @key: the lock_class_key for this class; used by mutex lock debugging * @@ -232,8 +230,7 @@ static void class_create_release(struct class *cls) * Note, the pointer created here is to be destroyed when finished by * making a call to class_destroy(). */ -struct class *__class_create(struct module *owner, const char *name, - struct lock_class_key *key) +struct class *__class_create(const char *name, struct lock_class_key *key) { struct class *cls; int retval; @@ -247,7 +244,7 @@ struct class *__class_create(struct module *owner, const char *name, cls->name = name; cls->class_release = class_create_release; - retval = __class_register(cls, owner, key); + retval = __class_register(cls, key); if (retval) goto error; diff --git a/include/linux/device/class.h b/include/linux/device/class.h index d1ba4ee235dc3..bf736f14f0c1b 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -25,7 +25,6 @@ struct fwnode_handle; /** * struct class - device classes * @name: Name of the class. - * @owner: The module owner. * @class_groups: Default attributes of this class. * @dev_groups: Default attributes of the devices that belong to the class. * @dev_kobj: The kobject that represents this class and links it into the hierarchy. @@ -53,7 +52,6 @@ struct fwnode_handle; */ struct class { const char *name; - struct module *owner; const struct attribute_group **class_groups; const struct attribute_group **dev_groups; @@ -85,16 +83,15 @@ struct class_dev_iter { extern struct kobject *sysfs_dev_block_kobj; extern struct kobject *sysfs_dev_char_kobj; extern int __must_check __class_register(struct class *class, - struct module *owner, struct lock_class_key *key); extern void class_unregister(struct class *class); /* This is a #define to keep the compiler from merging different * instances of the __key variable */ -#define class_register(class) \ -({ \ - static struct lock_class_key __key; \ - __class_register(class, THIS_MODULE, &__key); \ +#define class_register(class) \ +({ \ + static struct lock_class_key __key; \ + __class_register(class, &__key); \ }) struct class_compat; @@ -250,8 +247,7 @@ struct class_interface { extern int __must_check class_interface_register(struct class_interface *); extern void class_interface_unregister(struct class_interface *); -extern struct class * __must_check __class_create(struct module *owner, - const char *name, +extern struct class * __must_check __class_create(const char *name, struct lock_class_key *key); extern void class_destroy(struct class *cls); @@ -260,7 +256,7 @@ extern void class_destroy(struct class *cls); /** * class_create - create a struct class structure - * @owner: pointer to the module that is to "own" this struct class + * @owner: dummy pointer, does nothing, will be removed soon. * @name: pointer to a string for the name of this class. * * This is used to create a struct class pointer that can then be used @@ -274,7 +270,7 @@ extern void class_destroy(struct class *cls); #define class_create(owner, name) \ ({ \ static struct lock_class_key __key; \ - __class_create(owner, name, &__key); \ + __class_create(name, &__key); \ }) -- cgit v1.2.3 From a2fd6e42e4fb661e183977072022b7dd8dd65d90 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 13 Mar 2023 19:18:36 +0100 Subject: driver core: class: make class_dev_iter_init() options const class_dev_iter_init() does not modify the struct class or the struct device passed into it, so mark them as const * to enforce that. Cc: "Rafael J. Wysocki" Link: https://lore.kernel.org/r/20230313181843.1207845-5-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 4 ++-- include/linux/device/class.h | 4 ++-- 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index 9439c6c7466fb..5a60e88951654 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -284,8 +284,8 @@ EXPORT_SYMBOL_GPL(class_destroy); * otherwise if it is NULL, the iteration starts at the beginning of * the list. */ -void class_dev_iter_init(struct class_dev_iter *iter, struct class *class, - struct device *start, const struct device_type *type) +void class_dev_iter_init(struct class_dev_iter *iter, const struct class *class, + const struct device *start, const struct device_type *type) { struct klist_node *start_knode = NULL; diff --git a/include/linux/device/class.h b/include/linux/device/class.h index cda598fc5fa07..1f5cfae8db883 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -103,8 +103,8 @@ void class_compat_remove_link(struct class_compat *cls, struct device *dev, struct device *device_link); extern void class_dev_iter_init(struct class_dev_iter *iter, - struct class *class, - struct device *start, + const struct class *class, + const struct device *start, const struct device_type *type); extern struct device *class_dev_iter_next(struct class_dev_iter *iter); extern void class_dev_iter_exit(struct class_dev_iter *iter); -- cgit v1.2.3 From 69df024ebbf8b1d4d8f0808b5700688fed9e45e9 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 13 Mar 2023 19:18:37 +0100 Subject: driver core: class: make class_for_each_device() options const class_for_each_device() does not modify the struct class or the struct device passed into it, so mark them as const * to enforce that. Cc: "Rafael J. Wysocki" Link: https://lore.kernel.org/r/20230313181843.1207845-6-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 2 +- include/linux/device/class.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index 5a60e88951654..4937d660c5711 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -355,7 +355,7 @@ EXPORT_SYMBOL_GPL(class_dev_iter_exit); * @fn is allowed to do anything including calling back into class * code. There's no locking restriction. */ -int class_for_each_device(struct class *class, struct device *start, +int class_for_each_device(const struct class *class, const struct device *start, void *data, int (*fn)(struct device *, void *)) { struct class_dev_iter iter; diff --git a/include/linux/device/class.h b/include/linux/device/class.h index 1f5cfae8db883..fdbcd487e5087 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -109,7 +109,7 @@ extern void class_dev_iter_init(struct class_dev_iter *iter, extern struct device *class_dev_iter_next(struct class_dev_iter *iter); extern void class_dev_iter_exit(struct class_dev_iter *iter); -extern int class_for_each_device(struct class *class, struct device *start, +extern int class_for_each_device(const struct class *class, const struct device *start, void *data, int (*fn)(struct device *dev, void *data)); extern struct device *class_find_device(struct class *class, -- cgit v1.2.3 From cf41015ea8d3f2ae451d9b7e39ef42569caeb875 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 13 Mar 2023 19:18:38 +0100 Subject: driver core: class: make class_find_device*() options const The class_find_device*() functions do not modify the struct class or the struct device passed into it, so mark them as const * to enforce that. Cc: "Rafael J. Wysocki" Link: https://lore.kernel.org/r/20230313181843.1207845-7-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 2 +- include/linux/device/class.h | 25 ++++++++++++------------- 2 files changed, 13 insertions(+), 14 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index 4937d660c5711..52ba0187e66dc 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -402,7 +402,7 @@ EXPORT_SYMBOL_GPL(class_for_each_device); * @match is allowed to do anything including calling back into class * code. There's no locking restriction. */ -struct device *class_find_device(struct class *class, struct device *start, +struct device *class_find_device(const struct class *class, const struct device *start, const void *data, int (*match)(struct device *, const void *)) { diff --git a/include/linux/device/class.h b/include/linux/device/class.h index fdbcd487e5087..dfa8958105e73 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -112,8 +112,8 @@ extern void class_dev_iter_exit(struct class_dev_iter *iter); extern int class_for_each_device(const struct class *class, const struct device *start, void *data, int (*fn)(struct device *dev, void *data)); -extern struct device *class_find_device(struct class *class, - struct device *start, const void *data, +extern struct device *class_find_device(const struct class *class, + const struct device *start, const void *data, int (*match)(struct device *, const void *)); /** @@ -122,7 +122,7 @@ extern struct device *class_find_device(struct class *class, * @class: class type * @name: name of the device to match */ -static inline struct device *class_find_device_by_name(struct class *class, +static inline struct device *class_find_device_by_name(const struct class *class, const char *name) { return class_find_device(class, NULL, name, device_match_name); @@ -134,8 +134,8 @@ static inline struct device *class_find_device_by_name(struct class *class, * @class: class type * @np: of_node of the device to match. */ -static inline struct device * -class_find_device_by_of_node(struct class *class, const struct device_node *np) +static inline struct device *class_find_device_by_of_node(const struct class *class, + const struct device_node *np) { return class_find_device(class, NULL, np, device_match_of_node); } @@ -146,9 +146,8 @@ class_find_device_by_of_node(struct class *class, const struct device_node *np) * @class: class type * @fwnode: fwnode of the device to match. */ -static inline struct device * -class_find_device_by_fwnode(struct class *class, - const struct fwnode_handle *fwnode) +static inline struct device *class_find_device_by_fwnode(const struct class *class, + const struct fwnode_handle *fwnode) { return class_find_device(class, NULL, fwnode, device_match_fwnode); } @@ -159,7 +158,7 @@ class_find_device_by_fwnode(struct class *class, * @class: class type * @devt: device type of the device to match. */ -static inline struct device *class_find_device_by_devt(struct class *class, +static inline struct device *class_find_device_by_devt(const struct class *class, dev_t devt) { return class_find_device(class, NULL, &devt, device_match_devt); @@ -173,14 +172,14 @@ struct acpi_device; * @class: class type * @adev: ACPI_COMPANION device to match. */ -static inline struct device * -class_find_device_by_acpi_dev(struct class *class, const struct acpi_device *adev) +static inline struct device *class_find_device_by_acpi_dev(const struct class *class, + const struct acpi_device *adev) { return class_find_device(class, NULL, adev, device_match_acpi_dev); } #else -static inline struct device * -class_find_device_by_acpi_dev(struct class *class, const void *adev) +static inline struct device *class_find_device_by_acpi_dev(const struct class *class, + const void *adev) { return NULL; } -- cgit v1.2.3 From 80842a92907bd68454591f9c7a73778f130ac38f Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 13 Mar 2023 19:18:39 +0100 Subject: driver core: class: make class_create/remove_file*() options const The class_create_file*() and class_remove_file*() functions do not modify the struct class at all, so mark them as const * to enforce that. Cc: "Rafael J. Wysocki" Link: https://lore.kernel.org/r/20230313181843.1207845-8-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 4 ++-- include/linux/device/class.h | 10 +++++----- 2 files changed, 7 insertions(+), 7 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index 52ba0187e66dc..3d65221b0dcb4 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -87,7 +87,7 @@ static const struct kobj_type class_ktype = { static struct kset *class_kset; -int class_create_file_ns(struct class *cls, const struct class_attribute *attr, +int class_create_file_ns(const struct class *cls, const struct class_attribute *attr, const void *ns) { int error; @@ -101,7 +101,7 @@ int class_create_file_ns(struct class *cls, const struct class_attribute *attr, } EXPORT_SYMBOL_GPL(class_create_file_ns); -void class_remove_file_ns(struct class *cls, const struct class_attribute *attr, +void class_remove_file_ns(const struct class *cls, const struct class_attribute *attr, const void *ns) { if (cls) diff --git a/include/linux/device/class.h b/include/linux/device/class.h index dfa8958105e73..75c1451fcc637 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -200,20 +200,20 @@ struct class_attribute { #define CLASS_ATTR_WO(_name) \ struct class_attribute class_attr_##_name = __ATTR_WO(_name) -extern int __must_check class_create_file_ns(struct class *class, +extern int __must_check class_create_file_ns(const struct class *class, const struct class_attribute *attr, const void *ns); -extern void class_remove_file_ns(struct class *class, +extern void class_remove_file_ns(const struct class *class, const struct class_attribute *attr, const void *ns); -static inline int __must_check class_create_file(struct class *class, - const struct class_attribute *attr) +static inline int __must_check class_create_file(const struct class *class, + const struct class_attribute *attr) { return class_create_file_ns(class, attr, NULL); } -static inline void class_remove_file(struct class *class, +static inline void class_remove_file(const struct class *class, const struct class_attribute *attr) { return class_remove_file_ns(class, attr, NULL); -- cgit v1.2.3 From dcfbb67e48a2becfce7990386e985b9c45098ee5 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Fri, 24 Mar 2023 11:01:31 +0100 Subject: driver core: class: use lock_class_key already present in struct subsys_private In commit 37e98d9bedb5 ("driver core: bus: move lock_class_key into dynamic structure"), we moved the lock_class_key into the internal structure shared by busses and classes, but only used it for buses. Move the class code to use this structure as it is already present and being allocated, instead of the statically allocated on-the-stack variable that class_create() was using as part of a macro wrapper around the core function call. Reviewed-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20230324100132.1633647-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 15 +++++++++------ include/linux/device/class.h | 36 ++---------------------------------- 2 files changed, 11 insertions(+), 40 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index 3d65221b0dcb4..dbaeb79ae9176 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -154,9 +154,10 @@ static void class_remove_groups(struct class *cls, return sysfs_remove_groups(&cls->p->subsys.kobj, groups); } -int __class_register(struct class *cls, struct lock_class_key *key) +int class_register(struct class *cls) { struct subsys_private *cp; + struct lock_class_key *key; int error; pr_debug("device class '%s': registering\n", cls->name); @@ -167,6 +168,8 @@ int __class_register(struct class *cls, struct lock_class_key *key) klist_init(&cp->klist_devices, klist_class_dev_get, klist_class_dev_put); INIT_LIST_HEAD(&cp->interfaces); kset_init(&cp->glue_dirs); + key = &cp->lock_key; + lockdep_register_key(key); __mutex_init(&cp->mutex, "subsys mutex", key); error = kobject_set_name(&cp->subsys.kobj, "%s", cls->name); if (error) { @@ -201,7 +204,7 @@ err_out: cls->p = NULL; return error; } -EXPORT_SYMBOL_GPL(__class_register); +EXPORT_SYMBOL_GPL(class_register); void class_unregister(struct class *cls) { @@ -218,7 +221,7 @@ static void class_create_release(struct class *cls) } /** - * __class_create - create a struct class structure + * class_create - create a struct class structure * @name: pointer to a string for the name of this class. * @key: the lock_class_key for this class; used by mutex lock debugging * @@ -230,7 +233,7 @@ static void class_create_release(struct class *cls) * Note, the pointer created here is to be destroyed when finished by * making a call to class_destroy(). */ -struct class *__class_create(const char *name, struct lock_class_key *key) +struct class *class_create(const char *name) { struct class *cls; int retval; @@ -244,7 +247,7 @@ struct class *__class_create(const char *name, struct lock_class_key *key) cls->name = name; cls->class_release = class_create_release; - retval = __class_register(cls, key); + retval = class_register(cls); if (retval) goto error; @@ -254,7 +257,7 @@ error: kfree(cls); return ERR_PTR(retval); } -EXPORT_SYMBOL_GPL(__class_create); +EXPORT_SYMBOL_GPL(class_create); /** * class_destroy - destroys a struct class structure diff --git a/include/linux/device/class.h b/include/linux/device/class.h index 75c1451fcc637..03d2f99f84c52 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -82,18 +82,9 @@ struct class_dev_iter { extern struct kobject *sysfs_dev_block_kobj; extern struct kobject *sysfs_dev_char_kobj; -extern int __must_check __class_register(struct class *class, - struct lock_class_key *key); +extern int __must_check class_register(struct class *class); extern void class_unregister(struct class *class); -/* This is a #define to keep the compiler from merging different - * instances of the __key variable */ -#define class_register(class) \ -({ \ - static struct lock_class_key __key; \ - __class_register(class, &__key); \ -}) - struct class_compat; struct class_compat *class_compat_register(const char *name); void class_compat_unregister(struct class_compat *cls); @@ -246,30 +237,7 @@ struct class_interface { extern int __must_check class_interface_register(struct class_interface *); extern void class_interface_unregister(struct class_interface *); -extern struct class * __must_check __class_create(const char *name, - struct lock_class_key *key); +extern struct class * __must_check class_create(const char *name); extern void class_destroy(struct class *cls); -/* This is a #define to keep the compiler from merging different - * instances of the __key variable */ - -/** - * class_create - create a struct class structure - * @name: pointer to a string for the name of this class. - * - * This is used to create a struct class pointer that can then be used - * in calls to device_create(). - * - * Returns &struct class pointer on success, or ERR_PTR() on error. - * - * Note, the pointer created here is to be destroyed when finished by - * making a call to class_destroy(). - */ -#define class_create(name) \ -({ \ - static struct lock_class_key __key; \ - __class_create(name, &__key); \ -}) - - #endif /* _DEVICE_CLASS_H_ */ -- cgit v1.2.3 From 170848d4060d40220194c0af19f977a582f08922 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Mon, 27 Mar 2023 10:18:28 +0200 Subject: driver core: class: fix documentation for class_create() In commit dcfbb67e48a2 ("driver core: class: use lock_class_key already present in struct subsys_private") we removed the key parameter to the function class_create() but forgot to remove it from the kerneldoc, which causes a build warning. Fix that up by removing the key parameter from the documentation as it is now gone. Reported-by: Stephen Rothwell Fixes: dcfbb67e48a2 ("driver core: class: use lock_class_key already present in struct subsys_private") Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20230327081828.1087364-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 1 - 1 file changed, 1 deletion(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index dbaeb79ae9176..0f8938a171444 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -223,7 +223,6 @@ static void class_create_release(struct class *cls) /** * class_create - create a struct class structure * @name: pointer to a string for the name of this class. - * @key: the lock_class_key for this class; used by mutex lock debugging * * This is used to create a struct class pointer that can then be used * in calls to device_create(). -- cgit v1.2.3 From 517d4927aabe488144863e72b52bb3e506fecd34 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Sat, 25 Mar 2023 09:45:26 +0100 Subject: driver core: bus: constify class_unregister/destroy() The class_unregister() and class_destroy() function should be taking a const * to struct class, not just a *, so fix that up. Cc: "Rafael J. Wysocki" Link: https://lore.kernel.org/r/20230325084526.3622123-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 8 ++++---- include/linux/device/class.h | 4 ++-- 2 files changed, 6 insertions(+), 6 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index 0f8938a171444..8ae91e118827c 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -142,13 +142,13 @@ static void klist_class_dev_put(struct klist_node *n) put_device(dev); } -static int class_add_groups(struct class *cls, +static int class_add_groups(const struct class *cls, const struct attribute_group **groups) { return sysfs_create_groups(&cls->p->subsys.kobj, groups); } -static void class_remove_groups(struct class *cls, +static void class_remove_groups(const struct class *cls, const struct attribute_group **groups) { return sysfs_remove_groups(&cls->p->subsys.kobj, groups); @@ -206,7 +206,7 @@ err_out: } EXPORT_SYMBOL_GPL(class_register); -void class_unregister(struct class *cls) +void class_unregister(const struct class *cls) { pr_debug("device class '%s': unregistering\n", cls->name); class_remove_groups(cls, cls->class_groups); @@ -265,7 +265,7 @@ EXPORT_SYMBOL_GPL(class_create); * Note, the pointer to be destroyed must have been created with a call * to class_create(). */ -void class_destroy(struct class *cls) +void class_destroy(const struct class *cls) { if (IS_ERR_OR_NULL(cls)) return; diff --git a/include/linux/device/class.h b/include/linux/device/class.h index d3960733c0fa8..73436c578d373 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -83,7 +83,7 @@ struct class_dev_iter { extern struct kobject *sysfs_dev_block_kobj; int __must_check class_register(struct class *class); -void class_unregister(struct class *class); +void class_unregister(const struct class *class); struct class_compat; struct class_compat *class_compat_register(const char *name); @@ -231,6 +231,6 @@ int __must_check class_interface_register(struct class_interface *); void class_interface_unregister(struct class_interface *); struct class * __must_check class_create(const char *name); -void class_destroy(struct class *cls); +void class_destroy(const struct class *cls); #endif /* _DEVICE_CLASS_H_ */ -- cgit v1.2.3 From 75a2d4226b53710380d1017b3f4c88f937ddba78 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Sat, 25 Mar 2023 09:45:37 +0100 Subject: driver core: class: mark the struct class for sysfs callbacks as constant struct class should never be modified in a sysfs callback as there is nothing in the structure to modify, and frankly, the structure is almost never used in a sysfs callback, so mark it as constant to allow struct class to be moved to read-only memory. While we are touching all class sysfs callbacks also mark the attribute as constant as it can not be modified. The bonding code still uses this structure so it can not be removed from the function callbacks. Cc: "David S. Miller" Cc: "Rafael J. Wysocki" Cc: Bartosz Golaszewski Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Jens Axboe Cc: Johannes Berg Cc: Linus Walleij Cc: Minchan Kim Cc: Miquel Raynal Cc: Namjae Jeon Cc: Paolo Abeni Cc: Russ Weight Cc: Sergey Senozhatsky Cc: Steve French Cc: Vignesh Raghavendra Cc: linux-cifs@vger.kernel.org Cc: linux-gpio@vger.kernel.org Cc: linux-mtd@lists.infradead.org Cc: linux-rdma@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: netdev@vger.kernel.org Reviewed-by: Luis Chamberlain Link: https://lore.kernel.org/r/20230325084537.3622280-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/platforms/pseries/dlpar.c | 4 ++-- arch/powerpc/platforms/pseries/mobility.c | 4 ++-- drivers/base/class.c | 4 ++-- drivers/base/devcoredump.c | 4 ++-- drivers/base/firmware_loader/sysfs.c | 4 ++-- drivers/block/pktcdvd.c | 6 +++--- drivers/block/zram/zram_drv.c | 11 +++++------ drivers/gpio/gpiolib-sysfs.c | 8 ++++---- drivers/infiniband/core/user_mad.c | 4 ++-- drivers/mtd/ubi/build.c | 2 +- drivers/net/bonding/bond_sysfs.c | 18 +++++++++--------- drivers/s390/crypto/zcrypt_api.c | 8 ++++---- fs/ksmbd/server.c | 10 +++++----- include/linux/device/class.h | 9 +++++---- 14 files changed, 48 insertions(+), 48 deletions(-) (limited to 'drivers/base/class.c') diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c index 75ffdbcd28659..719c97a155edf 100644 --- a/arch/powerpc/platforms/pseries/dlpar.c +++ b/arch/powerpc/platforms/pseries/dlpar.c @@ -512,7 +512,7 @@ static int dlpar_parse_id_type(char **cmd, struct pseries_hp_errorlog *hp_elog) return 0; } -static ssize_t dlpar_store(struct class *class, struct class_attribute *attr, +static ssize_t dlpar_store(const struct class *class, const struct class_attribute *attr, const char *buf, size_t count) { struct pseries_hp_errorlog hp_elog; @@ -551,7 +551,7 @@ dlpar_store_out: return rc ? rc : count; } -static ssize_t dlpar_show(struct class *class, struct class_attribute *attr, +static ssize_t dlpar_show(const struct class *class, const struct class_attribute *attr, char *buf) { return sprintf(buf, "%s\n", "memory,cpu"); diff --git a/arch/powerpc/platforms/pseries/mobility.c b/arch/powerpc/platforms/pseries/mobility.c index 643d309d1bd05..6b25642adfa04 100644 --- a/arch/powerpc/platforms/pseries/mobility.c +++ b/arch/powerpc/platforms/pseries/mobility.c @@ -787,8 +787,8 @@ int rtas_syscall_dispatch_ibm_suspend_me(u64 handle) return pseries_migrate_partition(handle); } -static ssize_t migration_store(struct class *class, - struct class_attribute *attr, const char *buf, +static ssize_t migration_store(const struct class *class, + const struct class_attribute *attr, const char *buf, size_t count) { u64 streamid; diff --git a/drivers/base/class.c b/drivers/base/class.c index 8ae91e118827c..04de20e0dba86 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -482,8 +482,8 @@ void class_interface_unregister(struct class_interface *class_intf) } EXPORT_SYMBOL_GPL(class_interface_unregister); -ssize_t show_class_attr_string(struct class *class, - struct class_attribute *attr, char *buf) +ssize_t show_class_attr_string(const struct class *class, + const struct class_attribute *attr, char *buf) { struct class_attribute_string *cs; diff --git a/drivers/base/devcoredump.c b/drivers/base/devcoredump.c index 59aaf2e1375a6..91536ee05f144 100644 --- a/drivers/base/devcoredump.c +++ b/drivers/base/devcoredump.c @@ -167,7 +167,7 @@ static int devcd_free(struct device *dev, void *data) return 0; } -static ssize_t disabled_show(struct class *class, struct class_attribute *attr, +static ssize_t disabled_show(const struct class *class, const struct class_attribute *attr, char *buf) { return sysfs_emit(buf, "%d\n", devcd_disabled); @@ -197,7 +197,7 @@ static ssize_t disabled_show(struct class *class, struct class_attribute *attr, * so, above situation would not occur. */ -static ssize_t disabled_store(struct class *class, struct class_attribute *attr, +static ssize_t disabled_store(const struct class *class, const struct class_attribute *attr, const char *buf, size_t count) { long tmp = simple_strtol(buf, NULL, 10); diff --git a/drivers/base/firmware_loader/sysfs.c b/drivers/base/firmware_loader/sysfs.c index 56911d75b90a1..c9c93b47d9a51 100644 --- a/drivers/base/firmware_loader/sysfs.c +++ b/drivers/base/firmware_loader/sysfs.c @@ -25,7 +25,7 @@ void __fw_load_abort(struct fw_priv *fw_priv) } #ifdef CONFIG_FW_LOADER_USER_HELPER -static ssize_t timeout_show(struct class *class, struct class_attribute *attr, +static ssize_t timeout_show(const struct class *class, const struct class_attribute *attr, char *buf) { return sysfs_emit(buf, "%d\n", __firmware_loading_timeout()); @@ -44,7 +44,7 @@ static ssize_t timeout_show(struct class *class, struct class_attribute *attr, * * Note: zero means 'wait forever'. **/ -static ssize_t timeout_store(struct class *class, struct class_attribute *attr, +static ssize_t timeout_store(const struct class *class, const struct class_attribute *attr, const char *buf, size_t count) { int tmp_loading_timeout = simple_strtol(buf, NULL, 10); diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c index 642e3377441af..ba9bbdef9ef50 100644 --- a/drivers/block/pktcdvd.c +++ b/drivers/block/pktcdvd.c @@ -343,7 +343,7 @@ static void class_pktcdvd_release(struct class *cls) kfree(cls); } -static ssize_t device_map_show(struct class *c, struct class_attribute *attr, +static ssize_t device_map_show(const struct class *c, const struct class_attribute *attr, char *data) { int n = 0; @@ -364,7 +364,7 @@ static ssize_t device_map_show(struct class *c, struct class_attribute *attr, } static CLASS_ATTR_RO(device_map); -static ssize_t add_store(struct class *c, struct class_attribute *attr, +static ssize_t add_store(const struct class *c, const struct class_attribute *attr, const char *buf, size_t count) { unsigned int major, minor; @@ -385,7 +385,7 @@ static ssize_t add_store(struct class *c, struct class_attribute *attr, } static CLASS_ATTR_WO(add); -static ssize_t remove_store(struct class *c, struct class_attribute *attr, +static ssize_t remove_store(const struct class *c, const struct class_attribute *attr, const char *buf, size_t count) { unsigned int major, minor; diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index b7bb52f8dfbdf..3feadfb961142 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -2424,8 +2424,8 @@ static int zram_remove(struct zram *zram) * creates a new un-initialized zram device and returns back this device's * device_id (or an error code if it fails to create a new device). */ -static ssize_t hot_add_show(struct class *class, - struct class_attribute *attr, +static ssize_t hot_add_show(const struct class *class, + const struct class_attribute *attr, char *buf) { int ret; @@ -2438,11 +2438,10 @@ static ssize_t hot_add_show(struct class *class, return ret; return scnprintf(buf, PAGE_SIZE, "%d\n", ret); } -static struct class_attribute class_attr_hot_add = - __ATTR(hot_add, 0400, hot_add_show, NULL); +static CLASS_ATTR_RO(hot_add); -static ssize_t hot_remove_store(struct class *class, - struct class_attribute *attr, +static ssize_t hot_remove_store(const struct class *class, + const struct class_attribute *attr, const char *buf, size_t count) { diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c index 774755052618a..a895915affa59 100644 --- a/drivers/gpio/gpiolib-sysfs.c +++ b/drivers/gpio/gpiolib-sysfs.c @@ -426,8 +426,8 @@ ATTRIBUTE_GROUPS(gpiochip); * /sys/class/gpio/unexport ... write-only * integer N ... number of GPIO to unexport */ -static ssize_t export_store(struct class *class, - struct class_attribute *attr, +static ssize_t export_store(const struct class *class, + const struct class_attribute *attr, const char *buf, size_t len) { long gpio; @@ -478,8 +478,8 @@ done: } static CLASS_ATTR_WO(export); -static ssize_t unexport_store(struct class *class, - struct class_attribute *attr, +static ssize_t unexport_store(const struct class *class, + const struct class_attribute *attr, const char *buf, size_t len) { long gpio; diff --git a/drivers/infiniband/core/user_mad.c b/drivers/infiniband/core/user_mad.c index f83954180a338..0e9e04f8c6858 100644 --- a/drivers/infiniband/core/user_mad.c +++ b/drivers/infiniband/core/user_mad.c @@ -1229,8 +1229,8 @@ static char *umad_devnode(const struct device *dev, umode_t *mode) return kasprintf(GFP_KERNEL, "infiniband/%s", dev_name(dev)); } -static ssize_t abi_version_show(struct class *class, - struct class_attribute *attr, char *buf) +static ssize_t abi_version_show(const struct class *class, + const struct class_attribute *attr, char *buf) { return sysfs_emit(buf, "%d\n", IB_USER_MAD_ABI_VERSION); } diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c index ae6d35e3da9c0..32105bd358317 100644 --- a/drivers/mtd/ubi/build.c +++ b/drivers/mtd/ubi/build.c @@ -95,7 +95,7 @@ static DEFINE_SPINLOCK(ubi_devices_lock); /* "Show" method for files in '//class/ubi/' */ /* UBI version attribute ('//class/ubi/version') */ -static ssize_t version_show(struct class *class, struct class_attribute *attr, +static ssize_t version_show(const struct class *class, const struct class_attribute *attr, char *buf) { return sprintf(buf, "%d\n", UBI_VERSION); diff --git a/drivers/net/bonding/bond_sysfs.c b/drivers/net/bonding/bond_sysfs.c index 8996bd0a194ab..0bb59da249224 100644 --- a/drivers/net/bonding/bond_sysfs.c +++ b/drivers/net/bonding/bond_sysfs.c @@ -31,12 +31,12 @@ /* "show" function for the bond_masters attribute. * The class parameter is ignored. */ -static ssize_t bonding_show_bonds(struct class *cls, - struct class_attribute *attr, +static ssize_t bonding_show_bonds(const struct class *cls, + const struct class_attribute *attr, char *buf) { - struct bond_net *bn = - container_of(attr, struct bond_net, class_attr_bonding_masters); + const struct bond_net *bn = + container_of_const(attr, struct bond_net, class_attr_bonding_masters); int res = 0; struct bonding *bond; @@ -59,7 +59,7 @@ static ssize_t bonding_show_bonds(struct class *cls, return res; } -static struct net_device *bond_get_by_name(struct bond_net *bn, const char *ifname) +static struct net_device *bond_get_by_name(const struct bond_net *bn, const char *ifname) { struct bonding *bond; @@ -75,12 +75,12 @@ static struct net_device *bond_get_by_name(struct bond_net *bn, const char *ifna * * The class parameter is ignored. */ -static ssize_t bonding_store_bonds(struct class *cls, - struct class_attribute *attr, +static ssize_t bonding_store_bonds(const struct class *cls, + const struct class_attribute *attr, const char *buffer, size_t count) { - struct bond_net *bn = - container_of(attr, struct bond_net, class_attr_bonding_masters); + const struct bond_net *bn = + container_of_const(attr, struct bond_net, class_attr_bonding_masters); char command[IFNAMSIZ + 1] = {0, }; char *ifname; int rv, res = count; diff --git a/drivers/s390/crypto/zcrypt_api.c b/drivers/s390/crypto/zcrypt_api.c index 582ac301d3150..cff2eea88f98d 100644 --- a/drivers/s390/crypto/zcrypt_api.c +++ b/drivers/s390/crypto/zcrypt_api.c @@ -340,8 +340,8 @@ static const struct attribute_group *zcdn_dev_attr_groups[] = { NULL }; -static ssize_t zcdn_create_store(struct class *class, - struct class_attribute *attr, +static ssize_t zcdn_create_store(const struct class *class, + const struct class_attribute *attr, const char *buf, size_t count) { int rc; @@ -357,8 +357,8 @@ static ssize_t zcdn_create_store(struct class *class, static const struct class_attribute class_attr_zcdn_create = __ATTR(create, 0600, NULL, zcdn_create_store); -static ssize_t zcdn_destroy_store(struct class *class, - struct class_attribute *attr, +static ssize_t zcdn_destroy_store(const struct class *class, + const struct class_attribute *attr, const char *buf, size_t count) { int rc; diff --git a/fs/ksmbd/server.c b/fs/ksmbd/server.c index b5af3e43e6770..c2c958a5423ea 100644 --- a/fs/ksmbd/server.c +++ b/fs/ksmbd/server.c @@ -418,7 +418,7 @@ int server_queue_ctrl_reset_work(void) return __queue_ctrl_work(SERVER_CTRL_TYPE_RESET); } -static ssize_t stats_show(struct class *class, struct class_attribute *attr, +static ssize_t stats_show(const struct class *class, const struct class_attribute *attr, char *buf) { /* @@ -437,8 +437,8 @@ static ssize_t stats_show(struct class *class, struct class_attribute *attr, server_conf.ipc_last_active / HZ); } -static ssize_t kill_server_store(struct class *class, - struct class_attribute *attr, const char *buf, +static ssize_t kill_server_store(const struct class *class, + const struct class_attribute *attr, const char *buf, size_t len) { if (!sysfs_streq(buf, "hard")) @@ -458,7 +458,7 @@ static const char * const debug_type_strings[] = {"smb", "auth", "vfs", "oplock", "ipc", "conn", "rdma"}; -static ssize_t debug_show(struct class *class, struct class_attribute *attr, +static ssize_t debug_show(const struct class *class, const struct class_attribute *attr, char *buf) { ssize_t sz = 0; @@ -476,7 +476,7 @@ static ssize_t debug_show(struct class *class, struct class_attribute *attr, return sz; } -static ssize_t debug_store(struct class *class, struct class_attribute *attr, +static ssize_t debug_store(const struct class *class, const struct class_attribute *attr, const char *buf, size_t len) { int i; diff --git a/include/linux/device/class.h b/include/linux/device/class.h index 73436c578d373..b53728ca56fbc 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -174,10 +174,10 @@ static inline struct device *class_find_device_by_acpi_dev(const struct class *c struct class_attribute { struct attribute attr; - ssize_t (*show)(struct class *class, struct class_attribute *attr, + ssize_t (*show)(const struct class *class, const struct class_attribute *attr, char *buf); - ssize_t (*store)(struct class *class, struct class_attribute *attr, - const char *buf, size_t count); + ssize_t (*store)(const struct class *class, const struct class_attribute *attr, + const char *buf, size_t count); }; #define CLASS_ATTR_RW(_name) \ @@ -217,7 +217,8 @@ struct class_attribute_string { struct class_attribute_string class_attr_##_name = \ _CLASS_ATTR_STRING(_name, _mode, _str) -ssize_t show_class_attr_string(struct class *class, struct class_attribute *attr, char *buf); +ssize_t show_class_attr_string(const struct class *class, const struct class_attribute *attr, + char *buf); struct class_interface { struct list_head node; -- cgit v1.2.3 From 884f8ce42ccec9d0bf11d8bf9f111e5961ca1c82 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Sat, 25 Mar 2023 20:42:33 +0100 Subject: driver core: class: implement class_get/put without the private pointer. Much like what was done in commit 273afac615ad ("driver core: bus: implement bus_get/put() without the private pointer"), it is time to move the driver core away from using the internal private pointer in struct class in order to enable it to be always a constant and be placed in read-only memory in the future. First step in doing this is to create a helper function that turns a 'struct class' into 'struct subsys_private' called class_to_subsys(). class_to_subsys() walks the list of registered busses in the system and finds the matching one based on the pointer to the class itself. As this is a short list, and this function is not on any fast path, it should not be noticable. Implement class_get() and class_put() using this new helper function. Cc: "Rafael J. Wysocki" Link: https://lore.kernel.org/r/20230325194234.46588-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 81 ++++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 63 insertions(+), 18 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index 04de20e0dba86..c53d6f98cfc61 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -20,8 +20,70 @@ #include #include "base.h" +/* /sys/class */ +static struct kset *class_kset; + #define to_class_attr(_attr) container_of(_attr, struct class_attribute, attr) +/** + * class_to_subsys - Turn a struct class into a struct subsys_private + * + * @class: pointer to the struct bus_type to look up + * + * The driver core internals need to work on the subsys_private structure, not + * the external struct class pointer. This function walks the list of + * registered classes in the system and finds the matching one and returns the + * internal struct subsys_private that relates to that class. + * + * Note, the reference count of the return value is INCREMENTED if it is not + * NULL. A call to subsys_put() must be done when finished with the pointer in + * order for it to be properly freed. + */ +static struct subsys_private *class_to_subsys(const struct class *class) +{ + struct subsys_private *sp = NULL; + struct kobject *kobj; + + if (!class || !class_kset) + return NULL; + + spin_lock(&class_kset->list_lock); + + if (list_empty(&class_kset->list)) + goto done; + + list_for_each_entry(kobj, &class_kset->list, entry) { + struct kset *kset = container_of(kobj, struct kset, kobj); + + sp = container_of_const(kset, struct subsys_private, subsys); + if (sp->class == class) + goto done; + } + sp = NULL; +done: + sp = subsys_get(sp); + spin_unlock(&class_kset->list_lock); + return sp; +} + +static const struct class *class_get(const struct class *class) +{ + struct subsys_private *sp = class_to_subsys(class); + + if (sp) + return class; + return NULL; +} + +static void class_put(const struct class *class) +{ + struct subsys_private *sp = class_to_subsys(class); + + /* two puts are required as the call to bus_to_subsys incremented it again */ + subsys_put(sp); + subsys_put(sp); +} + static ssize_t class_attr_show(struct kobject *kobj, struct attribute *attr, char *buf) { @@ -83,10 +145,6 @@ static const struct kobj_type class_ktype = { .child_ns_type = class_child_ns_type, }; -/* Hotplug events for classes go to the class subsys */ -static struct kset *class_kset; - - int class_create_file_ns(const struct class *cls, const struct class_attribute *attr, const void *ns) { @@ -109,19 +167,6 @@ void class_remove_file_ns(const struct class *cls, const struct class_attribute } EXPORT_SYMBOL_GPL(class_remove_file_ns); -static struct class *class_get(struct class *cls) -{ - if (cls) - kset_get(&cls->p->subsys); - return cls; -} - -static void class_put(struct class *cls) -{ - if (cls) - kset_put(&cls->p->subsys); -} - static struct device *klist_class_to_dev(struct klist_node *n) { struct device_private *p = to_device_private_class(n); @@ -434,7 +479,7 @@ EXPORT_SYMBOL_GPL(class_find_device); int class_interface_register(struct class_interface *class_intf) { - struct class *parent; + const struct class *parent; struct class_dev_iter iter; struct device *dev; -- cgit v1.2.3 From 7b884b7f24b42fa25e92ed724ad82f137610afaf Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Sat, 25 Mar 2023 20:42:34 +0100 Subject: driver core: class.c: convert to only use class_to_subsys Now that class_to_subsys() can be used to get access to the internal class private pointer, convert the remaining few places in class.c that were accessing the pointer directly to use class_to_subsys() instead. By doing this, the need for class_get() and class_put() goes away as no one actually tries to increment the class structures anymore, only the internal dynamic one. Cc: "Rafael J. Wysocki" Link: https://lore.kernel.org/r/20230325194234.46588-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 113 +++++++++++++++++++++++++++------------------------ 1 file changed, 61 insertions(+), 52 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index c53d6f98cfc61..1f12bd5d56d9d 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -66,24 +66,6 @@ done: return sp; } -static const struct class *class_get(const struct class *class) -{ - struct subsys_private *sp = class_to_subsys(class); - - if (sp) - return class; - return NULL; -} - -static void class_put(const struct class *class) -{ - struct subsys_private *sp = class_to_subsys(class); - - /* two puts are required as the call to bus_to_subsys incremented it again */ - subsys_put(sp); - subsys_put(sp); -} - static ssize_t class_attr_show(struct kobject *kobj, struct attribute *attr, char *buf) { @@ -148,13 +130,15 @@ static const struct kobj_type class_ktype = { int class_create_file_ns(const struct class *cls, const struct class_attribute *attr, const void *ns) { + struct subsys_private *sp = class_to_subsys(cls); int error; - if (cls) - error = sysfs_create_file_ns(&cls->p->subsys.kobj, - &attr->attr, ns); - else - error = -EINVAL; + if (!sp) + return -EINVAL; + + error = sysfs_create_file_ns(&sp->subsys.kobj, &attr->attr, ns); + subsys_put(sp); + return error; } EXPORT_SYMBOL_GPL(class_create_file_ns); @@ -162,8 +146,13 @@ EXPORT_SYMBOL_GPL(class_create_file_ns); void class_remove_file_ns(const struct class *cls, const struct class_attribute *attr, const void *ns) { - if (cls) - sysfs_remove_file_ns(&cls->p->subsys.kobj, &attr->attr, ns); + struct subsys_private *sp = class_to_subsys(cls); + + if (!sp) + return; + + sysfs_remove_file_ns(&sp->subsys.kobj, &attr->attr, ns); + subsys_put(sp); } EXPORT_SYMBOL_GPL(class_remove_file_ns); @@ -187,18 +176,6 @@ static void klist_class_dev_put(struct klist_node *n) put_device(dev); } -static int class_add_groups(const struct class *cls, - const struct attribute_group **groups) -{ - return sysfs_create_groups(&cls->p->subsys.kobj, groups); -} - -static void class_remove_groups(const struct class *cls, - const struct attribute_group **groups) -{ - return sysfs_remove_groups(&cls->p->subsys.kobj, groups); -} - int class_register(struct class *cls) { struct subsys_private *cp; @@ -235,8 +212,7 @@ int class_register(struct class *cls) if (error) goto err_out; - error = class_add_groups(class_get(cls), cls->class_groups); - class_put(cls); + error = sysfs_create_groups(&cp->subsys.kobj, cls->class_groups); if (error) { kobject_del(&cp->subsys.kobj); kfree_const(cp->subsys.kobj.name); @@ -253,9 +229,16 @@ EXPORT_SYMBOL_GPL(class_register); void class_unregister(const struct class *cls) { + struct subsys_private *sp = class_to_subsys(cls); + + if (!sp) + return; + pr_debug("device class '%s': unregistering\n", cls->name); - class_remove_groups(cls, cls->class_groups); - kset_unregister(&cls->p->subsys); + + sysfs_remove_groups(&sp->subsys.kobj, cls->class_groups); + kset_unregister(&sp->subsys); + subsys_put(sp); } EXPORT_SYMBOL_GPL(class_unregister); @@ -334,11 +317,15 @@ EXPORT_SYMBOL_GPL(class_destroy); void class_dev_iter_init(struct class_dev_iter *iter, const struct class *class, const struct device *start, const struct device_type *type) { + struct subsys_private *sp = class_to_subsys(class); struct klist_node *start_knode = NULL; + if (!sp) + return; + if (start) start_knode = &start->p->knode_class; - klist_iter_init_node(&class->p->klist_devices, &iter->ki, start_knode); + klist_iter_init_node(&sp->klist_devices, &iter->ki, start_knode); iter->type = type; } EXPORT_SYMBOL_GPL(class_dev_iter_init); @@ -405,13 +392,14 @@ EXPORT_SYMBOL_GPL(class_dev_iter_exit); int class_for_each_device(const struct class *class, const struct device *start, void *data, int (*fn)(struct device *, void *)) { + struct subsys_private *sp = class_to_subsys(class); struct class_dev_iter iter; struct device *dev; int error = 0; if (!class) return -EINVAL; - if (!class->p) { + if (!sp) { WARN(1, "%s called for class '%s' before it was initialized", __func__, class->name); return -EINVAL; @@ -424,6 +412,7 @@ int class_for_each_device(const struct class *class, const struct device *start, break; } class_dev_iter_exit(&iter); + subsys_put(sp); return error; } @@ -453,12 +442,13 @@ struct device *class_find_device(const struct class *class, const struct device const void *data, int (*match)(struct device *, const void *)) { + struct subsys_private *sp = class_to_subsys(class); struct class_dev_iter iter; struct device *dev; if (!class) return NULL; - if (!class->p) { + if (!sp) { WARN(1, "%s called for class '%s' before it was initialized", __func__, class->name); return NULL; @@ -472,6 +462,7 @@ struct device *class_find_device(const struct class *class, const struct device } } class_dev_iter_exit(&iter); + subsys_put(sp); return dev; } @@ -479,6 +470,7 @@ EXPORT_SYMBOL_GPL(class_find_device); int class_interface_register(struct class_interface *class_intf) { + struct subsys_private *sp; const struct class *parent; struct class_dev_iter iter; struct device *dev; @@ -486,19 +478,25 @@ int class_interface_register(struct class_interface *class_intf) if (!class_intf || !class_intf->class) return -ENODEV; - parent = class_get(class_intf->class); - if (!parent) + parent = class_intf->class; + sp = class_to_subsys(parent); + if (!sp) return -EINVAL; - mutex_lock(&parent->p->mutex); - list_add_tail(&class_intf->node, &parent->p->interfaces); + /* + * Reference in sp is now incremented and will be dropped when + * the interface is removed in the call to class_interface_unregister() + */ + + mutex_lock(&sp->mutex); + list_add_tail(&class_intf->node, &sp->interfaces); if (class_intf->add_dev) { class_dev_iter_init(&iter, parent, NULL, NULL); while ((dev = class_dev_iter_next(&iter))) class_intf->add_dev(dev, class_intf); class_dev_iter_exit(&iter); } - mutex_unlock(&parent->p->mutex); + mutex_unlock(&sp->mutex); return 0; } @@ -506,6 +504,7 @@ EXPORT_SYMBOL_GPL(class_interface_register); void class_interface_unregister(struct class_interface *class_intf) { + struct subsys_private *sp; struct class *parent = class_intf->class; struct class_dev_iter iter; struct device *dev; @@ -513,7 +512,11 @@ void class_interface_unregister(struct class_interface *class_intf) if (!parent) return; - mutex_lock(&parent->p->mutex); + sp = class_to_subsys(parent); + if (!sp) + return; + + mutex_lock(&sp->mutex); list_del_init(&class_intf->node); if (class_intf->remove_dev) { class_dev_iter_init(&iter, parent, NULL, NULL); @@ -521,9 +524,15 @@ void class_interface_unregister(struct class_interface *class_intf) class_intf->remove_dev(dev, class_intf); class_dev_iter_exit(&iter); } - mutex_unlock(&parent->p->mutex); + mutex_unlock(&sp->mutex); - class_put(parent); + /* + * Decrement the reference count twice, once for the class_to_subsys() + * call in the start of this function, and the second one from the + * reference increment in class_interface_register() + */ + subsys_put(sp); + subsys_put(sp); } EXPORT_SYMBOL_GPL(class_interface_unregister); -- cgit v1.2.3 From 7d90e81a2d5edbd04037100bdd54d955bdd9b0d0 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Fri, 31 Mar 2023 11:33:12 +0200 Subject: driver core: core: move to use class_to_subsys() There are a number of places in core.c that need access to the private subsystem structure of struct class, so move them to use class_to_subsys() instead of accessing it directly. This requires exporting class_to_subsys() out of class.c, but keeping it local to the driver core. Reviewed-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20230331093318.82288-1-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/base.h | 2 + drivers/base/class.c | 2 +- drivers/base/core.c | 121 +++++++++++++++++++++++++++++++++------------------ 3 files changed, 81 insertions(+), 44 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/base.h b/drivers/base/base.h index 2867ca4ee4ce6..6296164bb7f33 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -73,6 +73,8 @@ static inline void subsys_put(struct subsys_private *sp) kset_put(&sp->subsys); } +struct subsys_private *class_to_subsys(const struct class *class); + struct driver_private { struct kobject kobj; struct klist klist_devices; diff --git a/drivers/base/class.c b/drivers/base/class.c index 1f12bd5d56d9d..68a6f9b56d193 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -39,7 +39,7 @@ static struct kset *class_kset; * NULL. A call to subsys_put() must be done when finished with the pointer in * order for it to be properly freed. */ -static struct subsys_private *class_to_subsys(const struct class *class) +struct subsys_private *class_to_subsys(const struct class *class) { struct subsys_private *sp = NULL; struct kobject *kobj; diff --git a/drivers/base/core.c b/drivers/base/core.c index 89249be22161b..e3bc34fcf779e 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -3149,8 +3149,8 @@ static const struct kobj_type class_dir_ktype = { .child_ns_type = class_dir_child_ns_type }; -static struct kobject * -class_dir_create_and_add(const struct class *class, struct kobject *parent_kobj) +static struct kobject *class_dir_create_and_add(struct subsys_private *sp, + struct kobject *parent_kobj) { struct class_dir *dir; int retval; @@ -3159,12 +3159,12 @@ class_dir_create_and_add(const struct class *class, struct kobject *parent_kobj) if (!dir) return ERR_PTR(-ENOMEM); - dir->class = class; + dir->class = sp->class; kobject_init(&dir->kobj, &class_dir_ktype); - dir->kobj.kset = &class->p->glue_dirs; + dir->kobj.kset = &sp->glue_dirs; - retval = kobject_add(&dir->kobj, parent_kobj, "%s", class->name); + retval = kobject_add(&dir->kobj, parent_kobj, "%s", sp->class->name); if (retval < 0) { kobject_put(&dir->kobj); return ERR_PTR(retval); @@ -3177,9 +3177,10 @@ static DEFINE_MUTEX(gdp_mutex); static struct kobject *get_device_parent(struct device *dev, struct device *parent) { + struct subsys_private *sp = class_to_subsys(dev->class); struct kobject *kobj = NULL; - if (dev->class) { + if (sp) { struct kobject *parent_kobj; struct kobject *k; @@ -3190,30 +3191,34 @@ static struct kobject *get_device_parent(struct device *dev, */ if (parent == NULL) parent_kobj = virtual_device_parent(dev); - else if (parent->class && !dev->class->ns_type) + else if (parent->class && !dev->class->ns_type) { + subsys_put(sp); return &parent->kobj; - else + } else { parent_kobj = &parent->kobj; + } mutex_lock(&gdp_mutex); /* find our class-directory at the parent and reference it */ - spin_lock(&dev->class->p->glue_dirs.list_lock); - list_for_each_entry(k, &dev->class->p->glue_dirs.list, entry) + spin_lock(&sp->glue_dirs.list_lock); + list_for_each_entry(k, &sp->glue_dirs.list, entry) if (k->parent == parent_kobj) { kobj = kobject_get(k); break; } - spin_unlock(&dev->class->p->glue_dirs.list_lock); + spin_unlock(&sp->glue_dirs.list_lock); if (kobj) { mutex_unlock(&gdp_mutex); + subsys_put(sp); return kobj; } /* or create a new class-directory at the parent device */ - k = class_dir_create_and_add(dev->class, parent_kobj); + k = class_dir_create_and_add(sp, parent_kobj); /* do not emit an uevent for this simple "glue" directory */ mutex_unlock(&gdp_mutex); + subsys_put(sp); return k; } @@ -3236,10 +3241,23 @@ static struct kobject *get_device_parent(struct device *dev, static inline bool live_in_glue_dir(struct kobject *kobj, struct device *dev) { - if (!kobj || !dev->class || - kobj->kset != &dev->class->p->glue_dirs) + struct subsys_private *sp; + bool retval; + + if (!kobj || !dev->class) return false; - return true; + + sp = class_to_subsys(dev->class); + if (!sp) + return false; + + if (kobj->kset == &sp->glue_dirs) + retval = true; + else + retval = false; + + subsys_put(sp); + return retval; } static inline struct kobject *get_glue_dir(struct device *dev) @@ -3336,6 +3354,7 @@ static void cleanup_glue_dir(struct device *dev, struct kobject *glue_dir) static int device_add_class_symlinks(struct device *dev) { struct device_node *of_node = dev_of_node(dev); + struct subsys_private *sp; int error; if (of_node) { @@ -3345,12 +3364,11 @@ static int device_add_class_symlinks(struct device *dev) /* An error here doesn't warrant bringing down the device */ } - if (!dev->class) + sp = class_to_subsys(dev->class); + if (!sp) return 0; - error = sysfs_create_link(&dev->kobj, - &dev->class->p->subsys.kobj, - "subsystem"); + error = sysfs_create_link(&dev->kobj, &sp->subsys.kobj, "subsystem"); if (error) goto out_devnode; @@ -3362,35 +3380,37 @@ static int device_add_class_symlinks(struct device *dev) } /* link in the class directory pointing to the device */ - error = sysfs_create_link(&dev->class->p->subsys.kobj, - &dev->kobj, dev_name(dev)); + error = sysfs_create_link(&sp->subsys.kobj, &dev->kobj, dev_name(dev)); if (error) goto out_device; - - return 0; + goto exit; out_device: sysfs_remove_link(&dev->kobj, "device"); - out_subsys: sysfs_remove_link(&dev->kobj, "subsystem"); out_devnode: sysfs_remove_link(&dev->kobj, "of_node"); +exit: + subsys_put(sp); return error; } static void device_remove_class_symlinks(struct device *dev) { + struct subsys_private *sp = class_to_subsys(dev->class); + if (dev_of_node(dev)) sysfs_remove_link(&dev->kobj, "of_node"); - if (!dev->class) + if (!sp) return; if (dev->parent && device_is_not_partition(dev)) sysfs_remove_link(&dev->kobj, "device"); sysfs_remove_link(&dev->kobj, "subsystem"); - sysfs_delete_link(&dev->class->p->subsys.kobj, &dev->kobj, dev_name(dev)); + sysfs_delete_link(&sp->subsys.kobj, &dev->kobj, dev_name(dev)); + subsys_put(sp); } /** @@ -3499,6 +3519,7 @@ static int device_private_init(struct device *dev) */ int device_add(struct device *dev) { + struct subsys_private *sp; struct device *parent; struct kobject *kobj; struct class_interface *class_intf; @@ -3627,18 +3648,18 @@ int device_add(struct device *dev) klist_add_tail(&dev->p->knode_parent, &parent->p->klist_children); - if (dev->class) { - mutex_lock(&dev->class->p->mutex); + sp = class_to_subsys(dev->class); + if (sp) { + mutex_lock(&sp->mutex); /* tie the class to the device */ - klist_add_tail(&dev->p->knode_class, - &dev->class->p->klist_devices); + klist_add_tail(&dev->p->knode_class, &sp->klist_devices); /* notify any interfaces that the device is here */ - list_for_each_entry(class_intf, - &dev->class->p->interfaces, node) + list_for_each_entry(class_intf, &sp->interfaces, node) if (class_intf->add_dev) class_intf->add_dev(dev, class_intf); - mutex_unlock(&dev->class->p->mutex); + mutex_unlock(&sp->mutex); + subsys_put(sp); } done: put_device(dev); @@ -3758,6 +3779,7 @@ EXPORT_SYMBOL_GPL(kill_device); */ void device_del(struct device *dev) { + struct subsys_private *sp; struct device *parent = dev->parent; struct kobject *glue_dir = NULL; struct class_interface *class_intf; @@ -3784,18 +3806,20 @@ void device_del(struct device *dev) device_remove_sys_dev_entry(dev); device_remove_file(dev, &dev_attr_dev); } - if (dev->class) { + + sp = class_to_subsys(dev->class); + if (sp) { device_remove_class_symlinks(dev); - mutex_lock(&dev->class->p->mutex); + mutex_lock(&sp->mutex); /* notify any interfaces that the device is now gone */ - list_for_each_entry(class_intf, - &dev->class->p->interfaces, node) + list_for_each_entry(class_intf, &sp->interfaces, node) if (class_intf->remove_dev) class_intf->remove_dev(dev, class_intf); /* remove the device from the class list */ klist_del(&dev->p->knode_class); - mutex_unlock(&dev->class->p->mutex); + mutex_unlock(&sp->mutex); + subsys_put(sp); } device_remove_file(dev, &dev_attr_uevent); device_remove_attrs(dev); @@ -4458,9 +4482,16 @@ int device_rename(struct device *dev, const char *new_name) } if (dev->class) { - error = sysfs_rename_link_ns(&dev->class->p->subsys.kobj, - kobj, old_device_name, + struct subsys_private *sp = class_to_subsys(dev->class); + + if (!sp) { + error = -EINVAL; + goto out; + } + + error = sysfs_rename_link_ns(&sp->subsys.kobj, kobj, old_device_name, new_name, kobject_namespace(kobj)); + subsys_put(sp); if (error) goto out; } @@ -4643,6 +4674,7 @@ int device_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid) { int error; struct kobject *kobj = &dev->kobj; + struct subsys_private *sp; dev = get_device(dev); if (!dev) @@ -4685,10 +4717,13 @@ int device_change_owner(struct device *dev, kuid_t kuid, kgid_t kgid) * directory entry for @dev to @kuid/@kgid. This ensures that the * symlink shows the same permissions as its target. */ - error = sysfs_link_change_owner(&dev->class->p->subsys.kobj, &dev->kobj, - dev_name(dev), kuid, kgid); - if (error) + sp = class_to_subsys(dev->class); + if (!sp) { + error = -EINVAL; goto out; + } + error = sysfs_link_change_owner(&sp->subsys.kobj, &dev->kobj, dev_name(dev), kuid, kgid); + subsys_put(sp); out: put_device(dev); -- cgit v1.2.3 From 6f14c02220c791d5c46b0f965b9340c58f3d503d Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Fri, 31 Mar 2023 11:33:13 +0200 Subject: driver core: create class_is_registered() Some classes (i.e. gpio), want to know if they have been registered or not, and poke around in the class's internal structures to try to figure this out. Because this is not really a good idea, provide a function for classes to call to try to figure this out. Note, this is racy as the state of the class could change at any moment in time after the call is made, but as usually a class only wants to know if it has been registered yet or not, it should be fairly safe to use, and is just as safe as the previous "poke at the class internals" check was. Move the gpiolib code to use this function as proof that it works properly. Cc: Bartosz Golaszewski Cc: Sebastian Reichel Cc: Benjamin Tissoires Cc: linux-gpio@vger.kernel.org Reviewed-by: Linus Walleij Reviewed-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20230331093318.82288-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 25 +++++++++++++++++++++++++ drivers/gpio/gpiolib-sysfs.c | 4 ++-- include/linux/device/class.h | 1 + 3 files changed, 28 insertions(+), 2 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index 68a6f9b56d193..a8a1bf9762908 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -634,6 +634,31 @@ void class_compat_remove_link(struct class_compat *cls, struct device *dev, } EXPORT_SYMBOL_GPL(class_compat_remove_link); +/** + * class_is_registered - determine if at this moment in time, a class is + * registered in the driver core or not. + * @class: the class to check + * + * Returns a boolean to state if the class is registered in the driver core + * or not. Note that the value could switch right after this call is made, + * so only use this in places where you "know" it is safe to do so (usually + * to determine if the specific class has been registered yet or not). + * + * Be careful in using this. + */ +bool class_is_registered(const struct class *class) +{ + struct subsys_private *sp = class_to_subsys(class); + bool is_initialized = false; + + if (sp) { + is_initialized = true; + subsys_put(sp); + } + return is_initialized; +} +EXPORT_SYMBOL_GPL(class_is_registered); + int __init classes_init(void) { class_kset = kset_create_and_add("class", NULL, NULL); diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c index a895915affa59..1a9b21731cc9a 100644 --- a/drivers/gpio/gpiolib-sysfs.c +++ b/drivers/gpio/gpiolib-sysfs.c @@ -554,7 +554,7 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change) int offset; /* can't export until sysfs is available ... */ - if (!gpio_class.p) { + if (!class_is_registered(&gpio_class)) { pr_debug("%s: called too early!\n", __func__); return -ENOENT; } @@ -728,7 +728,7 @@ int gpiochip_sysfs_register(struct gpio_device *gdev) * register later, in gpiolib_sysfs_init() ... here we just * verify that _some_ field of gpio_class got initialized. */ - if (!gpio_class.p) + if (!class_is_registered(&gpio_class)) return 0; /* diff --git a/include/linux/device/class.h b/include/linux/device/class.h index b53728ca56fbc..9cb5db0588c8e 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -84,6 +84,7 @@ extern struct kobject *sysfs_dev_block_kobj; int __must_check class_register(struct class *class); void class_unregister(const struct class *class); +bool class_is_registered(const struct class *class); struct class_compat; struct class_compat *class_compat_register(const char *name); -- cgit v1.2.3 From 2df418cf4b720fe3a0db4b4aab67be43d26af9dd Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Fri, 31 Mar 2023 11:33:14 +0200 Subject: driver core: class: remove subsystem private pointer from struct class Now that the last users of the subsystem private pointer in struct class are gone, the pointer can be removed, as no one is using it. One step closer to allowing struct class to be const and moved into read-only memory. Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20230331093318.82288-3-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 4 ---- include/linux/device/class.h | 2 -- 2 files changed, 6 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index a8a1bf9762908..fcfb295363cc2 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -97,8 +97,6 @@ static void class_release(struct kobject *kobj) pr_debug("class '%s': release.\n", class->name); - class->p = NULL; - if (class->class_release) class->class_release(class); else @@ -206,7 +204,6 @@ int class_register(struct class *cls) cp->subsys.kobj.kset = class_kset; cp->subsys.kobj.ktype = &class_ktype; cp->class = cls; - cls->p = cp; error = kset_register(&cp->subsys); if (error) @@ -222,7 +219,6 @@ int class_register(struct class *cls) err_out: kfree(cp); - cls->p = NULL; return error; } EXPORT_SYMBOL_GPL(class_register); diff --git a/include/linux/device/class.h b/include/linux/device/class.h index 9cb5db0588c8e..f7aad64e256ad 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -71,8 +71,6 @@ struct class { void (*get_ownership)(const struct device *dev, kuid_t *uid, kgid_t *gid); const struct dev_pm_ops *pm; - - struct subsys_private *p; }; struct class_dev_iter { -- cgit v1.2.3 From e78195d52981fc634a4e1e66610a316088bd7458 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Fri, 31 Mar 2023 11:33:16 +0200 Subject: driver core: class: remove dev_kobj from struct class The dev_kobj field in struct class is now only written to, but never read from, so it can be removed as it is useless. Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/20230331093318.82288-5-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman --- block/genhd.c | 1 - drivers/base/class.c | 4 ---- include/linux/device/class.h | 2 -- 3 files changed, 7 deletions(-) (limited to 'drivers/base/class.c') diff --git a/block/genhd.c b/block/genhd.c index e1e1230b1b9f6..af7208a37c535 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -899,7 +899,6 @@ static int __init genhd_device_init(void) { int error; - block_class.dev_kobj = sysfs_dev_block_kobj; error = class_register(&block_class); if (unlikely(error)) return error; diff --git a/drivers/base/class.c b/drivers/base/class.c index fcfb295363cc2..06b96d6faa19c 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -197,10 +197,6 @@ int class_register(struct class *cls) return error; } - /* set the default /sys/dev directory for devices of this class */ - if (!cls->dev_kobj) - cls->dev_kobj = sysfs_dev_char_kobj; - cp->subsys.kobj.kset = class_kset; cp->subsys.kobj.ktype = &class_ktype; cp->class = cls; diff --git a/include/linux/device/class.h b/include/linux/device/class.h index f7aad64e256ad..e946642c314e7 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -27,7 +27,6 @@ struct fwnode_handle; * @name: Name of the class. * @class_groups: Default attributes of this class. * @dev_groups: Default attributes of the devices that belong to the class. - * @dev_kobj: The kobject that represents this class and links it into the hierarchy. * @dev_uevent: Called when a device is added, removed from this class, or a * few other things that generate uevents to add the environment * variables. @@ -55,7 +54,6 @@ struct class { const struct attribute_group **class_groups; const struct attribute_group **dev_groups; - struct kobject *dev_kobj; int (*dev_uevent)(const struct device *dev, struct kobj_uevent_env *env); char *(*devnode)(const struct device *dev, umode_t *mode); -- cgit v1.2.3 From f326ea63ecc683b3dc88d8ee4f598598d4ed3b39 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Sat, 1 Apr 2023 12:09:26 +0200 Subject: driver core: class: fix slab-use-after-free Read in class_register() Syzbot found that we had forgotten to unregister the lock_class_key when using it in commit dcfbb67e48a2 ("driver core: class: use lock_class_key already present in struct subsys_private") so fix that up and correctly release it when done. Cc: "Rafael J. Wysocki" Reported-and-tested-by: Fixes: dcfbb67e48a2 ("driver core: class: use lock_class_key already present in struct subsys_private") Link: https://lore.kernel.org/r/2023040126-blandness-duckling-bd55@gregkh Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index 06b96d6faa19c..65502bd7d5c57 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -103,6 +103,7 @@ static void class_release(struct kobject *kobj) pr_debug("class '%s' does not have a release() function, " "be careful\n", class->name); + lockdep_unregister_key(&cp->lock_key); kfree(cp); } -- cgit v1.2.3 From 979207cac517833c828133ffb2633bcdf6edce00 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Sun, 2 Apr 2023 19:58:46 +0200 Subject: driver core: class: mark class_release() as taking a const * The struct class callback, class_release(), is only called in 2 places, the pcmcia cardservices code, and in the class driver core code. Both places it is safe to mark the structure as a const *, to allow us to in the future mark all struct class usages as constant and move into read-only memory. Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/2023040248-outrage-obsolete-5a9a@gregkh Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 2 +- drivers/pcmcia/cs.c | 2 +- include/linux/device/class.h | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index 65502bd7d5c57..53fc7052340c4 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -235,7 +235,7 @@ void class_unregister(const struct class *cls) } EXPORT_SYMBOL_GPL(class_unregister); -static void class_create_release(struct class *cls) +static void class_create_release(const struct class *cls) { pr_debug("%s called for %s\n", __func__, cls->name); kfree(cls); diff --git a/drivers/pcmcia/cs.c b/drivers/pcmcia/cs.c index e3224e49c43fd..5658745c398f5 100644 --- a/drivers/pcmcia/cs.c +++ b/drivers/pcmcia/cs.c @@ -824,7 +824,7 @@ static int pcmcia_socket_uevent(const struct device *dev, static struct completion pcmcia_unload; -static void pcmcia_release_socket_class(struct class *data) +static void pcmcia_release_socket_class(const struct class *data) { complete(&pcmcia_unload); } diff --git a/include/linux/device/class.h b/include/linux/device/class.h index 7e4a1a6329f47..f3c418fa129a0 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -58,7 +58,7 @@ struct class { int (*dev_uevent)(const struct device *dev, struct kobj_uevent_env *env); char *(*devnode)(const struct device *dev, umode_t *mode); - void (*class_release)(struct class *class); + void (*class_release)(const struct class *class); void (*dev_release)(struct device *dev); int (*shutdown_pre)(struct device *dev); -- cgit v1.2.3 From 43a7206b0963c2153c95d6985624d1dc1b3abd4d Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Sun, 2 Apr 2023 19:58:47 +0200 Subject: driver core: class: make class_register() take a const * Now that the class code is cleaned up to not modify the class pointer registered with it, change class_register() to take a const * to allow the structure to be placed into read-only memory. Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/2023040248-customary-release-4aec@gregkh Signed-off-by: Greg Kroah-Hartman --- drivers/base/base.h | 2 +- drivers/base/class.c | 6 +++--- include/linux/device/class.h | 2 +- 3 files changed, 5 insertions(+), 5 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/base.h b/drivers/base/base.h index e96f3343fd7c6..eb4c0ace92420 100644 --- a/drivers/base/base.h +++ b/drivers/base/base.h @@ -54,7 +54,7 @@ struct subsys_private { struct device *dev_root; struct kset glue_dirs; - struct class *class; + const struct class *class; struct lock_class_key lock_key; }; diff --git a/drivers/base/class.c b/drivers/base/class.c index 53fc7052340c4..05bce79d3d191 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -93,7 +93,7 @@ static ssize_t class_attr_store(struct kobject *kobj, struct attribute *attr, static void class_release(struct kobject *kobj) { struct subsys_private *cp = to_subsys_private(kobj); - struct class *class = cp->class; + const struct class *class = cp->class; pr_debug("class '%s': release.\n", class->name); @@ -110,7 +110,7 @@ static void class_release(struct kobject *kobj) static const struct kobj_ns_type_operations *class_child_ns_type(const struct kobject *kobj) { const struct subsys_private *cp = to_subsys_private(kobj); - struct class *class = cp->class; + const struct class *class = cp->class; return class->ns_type; } @@ -175,7 +175,7 @@ static void klist_class_dev_put(struct klist_node *n) put_device(dev); } -int class_register(struct class *cls) +int class_register(const struct class *cls) { struct subsys_private *cp; struct lock_class_key *key; diff --git a/include/linux/device/class.h b/include/linux/device/class.h index f3c418fa129a0..4bf46f9bbb56e 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -76,7 +76,7 @@ struct class_dev_iter { const struct device_type *type; }; -int __must_check class_register(struct class *class); +int __must_check class_register(const struct class *class); void class_unregister(const struct class *class); bool class_is_registered(const struct class *class); -- cgit v1.2.3 From 6b0d49be81cf4f1cf30ebd079cbf4643cab0a01d Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Sun, 2 Apr 2023 19:58:48 +0200 Subject: driver core: class: mark the struct class in struct class_interface constant The struct class pointer in struct class_interface is never modified, so mark it as const so that no one accidentally tries to modify it in the future. Acked-by: Rafael J. Wysocki Link: https://lore.kernel.org/r/2023040249-handball-gruffly-5da7@gregkh Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 2 +- include/linux/device/class.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index 05bce79d3d191..ad8b9f163fd20 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -498,7 +498,7 @@ EXPORT_SYMBOL_GPL(class_interface_register); void class_interface_unregister(struct class_interface *class_intf) { struct subsys_private *sp; - struct class *parent = class_intf->class; + const struct class *parent = class_intf->class; struct class_dev_iter iter; struct device *dev; diff --git a/include/linux/device/class.h b/include/linux/device/class.h index 4bf46f9bbb56e..53287aa105b8e 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -217,7 +217,7 @@ ssize_t show_class_attr_string(const struct class *class, const struct class_att struct class_interface { struct list_head node; - struct class *class; + const struct class *class; int (*add_dev) (struct device *, struct class_interface *); void (*remove_dev) (struct device *, struct class_interface *); -- cgit v1.2.3 From 2243acd50ac4026e93ac4f024109be6dbd7f9098 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Sun, 2 Apr 2023 19:58:49 +0200 Subject: driver core: class: remove struct class_interface * from callbacks The add_dev and remove_dev callbacks in struct class_interface currently pass in a pointer back to the class_interface structure that is calling them, but none of the callback implementations actually use this pointer as it is pointless (the structure is known, the driver passed it in in the first place if it is really needed again.) So clean this up and just remove the pointer from the callbacks and fix up all callback functions. Cc: Jean Delvare Cc: Guenter Roeck Cc: "David S. Miller" Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Cc: Kurt Schwemmer Cc: Jon Mason Cc: Dave Jiang Cc: Allen Hubbe Cc: Dominik Brodowski Cc: Matt Porter Cc: Alexandre Bounine Cc: "James E.J. Bottomley" Cc: "Martin K. Petersen" Cc: Doug Gilbert Cc: John Stultz Cc: Thomas Gleixner Cc: Stephen Boyd Cc: Hans de Goede Cc: Andrew Morton Cc: Wang Weiyang Cc: Yang Yingliang Cc: Jakob Koschel Cc: Cai Xinchen Acked-by: Rafael J. Wysocki Acked-by: Logan Gunthorpe Link: https://lore.kernel.org/r/2023040250-pushover-platter-509c@gregkh Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 4 ++-- drivers/base/core.c | 10 ++++------ drivers/hwmon/drivetemp.c | 4 ++-- drivers/net/rionet.c | 3 +-- drivers/ntb/hw/mscc/ntb_hw_switchtec.c | 6 ++---- drivers/pcmcia/ds.c | 6 ++---- drivers/pcmcia/rsrc_nonstatic.c | 6 ++---- drivers/rapidio/devices/rio_mport_cdev.c | 7 ++----- drivers/rapidio/rio_cm.c | 8 ++------ drivers/scsi/ses.c | 6 ++---- drivers/scsi/sg.c | 8 ++++---- include/linux/device/class.h | 4 ++-- kernel/time/alarmtimer.c | 3 +-- 13 files changed, 28 insertions(+), 47 deletions(-) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index ad8b9f163fd20..ac1808d1a2e8f 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -486,7 +486,7 @@ int class_interface_register(struct class_interface *class_intf) if (class_intf->add_dev) { class_dev_iter_init(&iter, parent, NULL, NULL); while ((dev = class_dev_iter_next(&iter))) - class_intf->add_dev(dev, class_intf); + class_intf->add_dev(dev); class_dev_iter_exit(&iter); } mutex_unlock(&sp->mutex); @@ -514,7 +514,7 @@ void class_interface_unregister(struct class_interface *class_intf) if (class_intf->remove_dev) { class_dev_iter_init(&iter, parent, NULL, NULL); while ((dev = class_dev_iter_next(&iter))) - class_intf->remove_dev(dev, class_intf); + class_intf->remove_dev(dev); class_dev_iter_exit(&iter); } mutex_unlock(&sp->mutex); diff --git a/drivers/base/core.c b/drivers/base/core.c index 64d188be4df95..7a42d1b6b721c 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -541,8 +541,7 @@ static struct class devlink_class = { .dev_release = devlink_dev_release, }; -static int devlink_add_symlinks(struct device *dev, - struct class_interface *class_intf) +static int devlink_add_symlinks(struct device *dev) { int ret; size_t len; @@ -591,8 +590,7 @@ out: return ret; } -static void devlink_remove_symlinks(struct device *dev, - struct class_interface *class_intf) +static void devlink_remove_symlinks(struct device *dev) { struct device_link *link = to_devlink(dev); size_t len; @@ -3647,7 +3645,7 @@ int device_add(struct device *dev) /* notify any interfaces that the device is here */ list_for_each_entry(class_intf, &sp->interfaces, node) if (class_intf->add_dev) - class_intf->add_dev(dev, class_intf); + class_intf->add_dev(dev); mutex_unlock(&sp->mutex); subsys_put(sp); } @@ -3805,7 +3803,7 @@ void device_del(struct device *dev) /* notify any interfaces that the device is now gone */ list_for_each_entry(class_intf, &sp->interfaces, node) if (class_intf->remove_dev) - class_intf->remove_dev(dev, class_intf); + class_intf->remove_dev(dev); /* remove the device from the class list */ klist_del(&dev->p->knode_class); mutex_unlock(&sp->mutex); diff --git a/drivers/hwmon/drivetemp.c b/drivers/hwmon/drivetemp.c index 8e5759b423902..86171031ddc5a 100644 --- a/drivers/hwmon/drivetemp.c +++ b/drivers/hwmon/drivetemp.c @@ -550,7 +550,7 @@ static const struct hwmon_chip_info drivetemp_chip_info = { * The device argument points to sdev->sdev_dev. Its parent is * sdev->sdev_gendev, which we can use to get the scsi_device pointer. */ -static int drivetemp_add(struct device *dev, struct class_interface *intf) +static int drivetemp_add(struct device *dev) { struct scsi_device *sdev = to_scsi_device(dev->parent); struct drivetemp_data *st; @@ -585,7 +585,7 @@ abort: return err; } -static void drivetemp_remove(struct device *dev, struct class_interface *intf) +static void drivetemp_remove(struct device *dev) { struct drivetemp_data *st, *tmp; diff --git a/drivers/net/rionet.c b/drivers/net/rionet.c index fbcb9d05da649..4eececc945138 100644 --- a/drivers/net/rionet.c +++ b/drivers/net/rionet.c @@ -662,8 +662,7 @@ static int rionet_shutdown(struct notifier_block *nb, unsigned long code, return NOTIFY_DONE; } -static void rionet_remove_mport(struct device *dev, - struct class_interface *class_intf) +static void rionet_remove_mport(struct device *dev) { struct rio_mport *mport = to_rio_mport(dev); struct net_device *ndev; diff --git a/drivers/ntb/hw/mscc/ntb_hw_switchtec.c b/drivers/ntb/hw/mscc/ntb_hw_switchtec.c index 88ae18b0efa8d..d6bbcc7b5b90d 100644 --- a/drivers/ntb/hw/mscc/ntb_hw_switchtec.c +++ b/drivers/ntb/hw/mscc/ntb_hw_switchtec.c @@ -1470,8 +1470,7 @@ static int switchtec_ntb_reinit_peer(struct switchtec_ntb *sndev) return rc; } -static int switchtec_ntb_add(struct device *dev, - struct class_interface *class_intf) +static int switchtec_ntb_add(struct device *dev) { struct switchtec_dev *stdev = to_stdev(dev); struct switchtec_ntb *sndev; @@ -1541,8 +1540,7 @@ free_and_exit: return rc; } -static void switchtec_ntb_remove(struct device *dev, - struct class_interface *class_intf) +static void switchtec_ntb_remove(struct device *dev) { struct switchtec_dev *stdev = to_stdev(dev); struct switchtec_ntb *sndev = stdev->sndev; diff --git a/drivers/pcmcia/ds.c b/drivers/pcmcia/ds.c index c8087efa5e4af..d500e5dbbc3f5 100644 --- a/drivers/pcmcia/ds.c +++ b/drivers/pcmcia/ds.c @@ -1335,8 +1335,7 @@ static struct pcmcia_callback pcmcia_bus_callback = { .resume = pcmcia_bus_resume, }; -static int pcmcia_bus_add_socket(struct device *dev, - struct class_interface *class_intf) +static int pcmcia_bus_add_socket(struct device *dev) { struct pcmcia_socket *socket = dev_get_drvdata(dev); int ret; @@ -1369,8 +1368,7 @@ static int pcmcia_bus_add_socket(struct device *dev, return 0; } -static void pcmcia_bus_remove_socket(struct device *dev, - struct class_interface *class_intf) +static void pcmcia_bus_remove_socket(struct device *dev) { struct pcmcia_socket *socket = dev_get_drvdata(dev); diff --git a/drivers/pcmcia/rsrc_nonstatic.c b/drivers/pcmcia/rsrc_nonstatic.c index ad1141fddb4cc..471e0c5815f39 100644 --- a/drivers/pcmcia/rsrc_nonstatic.c +++ b/drivers/pcmcia/rsrc_nonstatic.c @@ -1200,8 +1200,7 @@ static const struct attribute_group rsrc_attributes = { .attrs = pccard_rsrc_attributes, }; -static int pccard_sysfs_add_rsrc(struct device *dev, - struct class_interface *class_intf) +static int pccard_sysfs_add_rsrc(struct device *dev) { struct pcmcia_socket *s = dev_get_drvdata(dev); @@ -1210,8 +1209,7 @@ static int pccard_sysfs_add_rsrc(struct device *dev, return sysfs_create_group(&dev->kobj, &rsrc_attributes); } -static void pccard_sysfs_remove_rsrc(struct device *dev, - struct class_interface *class_intf) +static void pccard_sysfs_remove_rsrc(struct device *dev) { struct pcmcia_socket *s = dev_get_drvdata(dev); diff --git a/drivers/rapidio/devices/rio_mport_cdev.c b/drivers/rapidio/devices/rio_mport_cdev.c index deb96c3160a70..a115730ebf146 100644 --- a/drivers/rapidio/devices/rio_mport_cdev.c +++ b/drivers/rapidio/devices/rio_mport_cdev.c @@ -2536,10 +2536,8 @@ static void mport_cdev_remove(struct mport_dev *md) /* * mport_add_mport() - Add rio_mport from LDM device struct * @dev: Linux device model struct - * @class_intf: Linux class_interface */ -static int mport_add_mport(struct device *dev, - struct class_interface *class_intf) +static int mport_add_mport(struct device *dev) { struct rio_mport *mport = NULL; struct mport_dev *chdev = NULL; @@ -2559,8 +2557,7 @@ static int mport_add_mport(struct device *dev, * mport_remove_mport() - Remove rio_mport from global list * TODO remove device from global mport_dev list */ -static void mport_remove_mport(struct device *dev, - struct class_interface *class_intf) +static void mport_remove_mport(struct device *dev) { struct rio_mport *mport = NULL; struct mport_dev *chdev; diff --git a/drivers/rapidio/rio_cm.c b/drivers/rapidio/rio_cm.c index acaf9cda014c1..49f8d111e5462 100644 --- a/drivers/rapidio/rio_cm.c +++ b/drivers/rapidio/rio_cm.c @@ -2087,13 +2087,11 @@ static int riocm_cdev_add(dev_t devno) /* * riocm_add_mport - add new local mport device into channel management core * @dev: device object associated with mport - * @class_intf: class interface * * When a new mport device is added, CM immediately reserves inbound and * outbound RapidIO mailboxes that will be used. */ -static int riocm_add_mport(struct device *dev, - struct class_interface *class_intf) +static int riocm_add_mport(struct device *dev) { int rc; int i; @@ -2166,14 +2164,12 @@ static int riocm_add_mport(struct device *dev, /* * riocm_remove_mport - remove local mport device from channel management core * @dev: device object associated with mport - * @class_intf: class interface * * Removes a local mport device from the list of registered devices that provide * channel management services. Returns an error if the specified mport is not * registered with the CM core. */ -static void riocm_remove_mport(struct device *dev, - struct class_interface *class_intf) +static void riocm_remove_mport(struct device *dev) { struct rio_mport *mport = to_rio_mport(dev); struct cm_dev *cm; diff --git a/drivers/scsi/ses.c b/drivers/scsi/ses.c index b11a9162e73aa..57feb0cae896f 100644 --- a/drivers/scsi/ses.c +++ b/drivers/scsi/ses.c @@ -663,8 +663,7 @@ static void ses_match_to_enclosure(struct enclosure_device *edev, } } -static int ses_intf_add(struct device *cdev, - struct class_interface *intf) +static int ses_intf_add(struct device *cdev) { struct scsi_device *sdev = to_scsi_device(cdev->parent); struct scsi_device *tmp_sdev; @@ -869,8 +868,7 @@ static void ses_intf_remove_enclosure(struct scsi_device *sdev) enclosure_unregister(edev); } -static void ses_intf_remove(struct device *cdev, - struct class_interface *intf) +static void ses_intf_remove(struct device *cdev) { struct scsi_device *sdev = to_scsi_device(cdev->parent); diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 4997f880d4a43..037f8c98a6d36 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -96,8 +96,8 @@ static int scatter_elem_sz_prev = SG_SCATTER_SZ; #define SG_SECTOR_SZ 512 -static int sg_add_device(struct device *, struct class_interface *); -static void sg_remove_device(struct device *, struct class_interface *); +static int sg_add_device(struct device *); +static void sg_remove_device(struct device *); static DEFINE_IDR(sg_index_idr); static DEFINE_RWLOCK(sg_index_lock); /* Also used to lock @@ -1488,7 +1488,7 @@ out_unlock: } static int -sg_add_device(struct device *cl_dev, struct class_interface *cl_intf) +sg_add_device(struct device *cl_dev) { struct scsi_device *scsidp = to_scsi_device(cl_dev->parent); Sg_device *sdp = NULL; @@ -1578,7 +1578,7 @@ sg_device_destroy(struct kref *kref) } static void -sg_remove_device(struct device *cl_dev, struct class_interface *cl_intf) +sg_remove_device(struct device *cl_dev) { struct scsi_device *scsidp = to_scsi_device(cl_dev->parent); Sg_device *sdp = dev_get_drvdata(cl_dev); diff --git a/include/linux/device/class.h b/include/linux/device/class.h index 53287aa105b8e..9deeaeb457bba 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -219,8 +219,8 @@ struct class_interface { struct list_head node; const struct class *class; - int (*add_dev) (struct device *, struct class_interface *); - void (*remove_dev) (struct device *, struct class_interface *); + int (*add_dev) (struct device *dev); + void (*remove_dev) (struct device *dev); }; int __must_check class_interface_register(struct class_interface *); diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index 7e5dff602585d..82b28ab0f328a 100644 --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -81,8 +81,7 @@ struct rtc_device *alarmtimer_get_rtcdev(void) } EXPORT_SYMBOL_GPL(alarmtimer_get_rtcdev); -static int alarmtimer_rtc_add_device(struct device *dev, - struct class_interface *class_intf) +static int alarmtimer_rtc_add_device(struct device *dev) { unsigned long flags; struct rtc_device *rtc = to_rtc_device(dev); -- cgit v1.2.3 From ddaf098ea779b3c1302c7843f6ff01e89b1fd380 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Tue, 16 May 2023 21:20:14 +0200 Subject: driver core: class: properly reference count class_dev_iter() When class_dev_iter is initialized, the reference count for the subsys private structure is incremented, but never decremented, causing a memory leak over time. To resolve this, save off a pointer to the internal structure into the class_dev_iter structure and then when the iterator is finished, drop the reference count. Reported-and-tested-by: syzbot+e7afd76ad060fa0d2605@syzkaller.appspotmail.com Fixes: 7b884b7f24b4 ("driver core: class.c: convert to only use class_to_subsys") Reported-by: Mirsad Goran Todorovac Cc: Alan Stern Acked-by: Rafael J. Wysocki Tested-by: Mirsad Goran Todorovac Link: https://lore.kernel.org/r/2023051610-stove-condense-9a77@gregkh Signed-off-by: Greg Kroah-Hartman --- drivers/base/class.c | 2 ++ include/linux/device/class.h | 1 + 2 files changed, 3 insertions(+) (limited to 'drivers/base/class.c') diff --git a/drivers/base/class.c b/drivers/base/class.c index ac1808d1a2e8f..05d9df90f621b 100644 --- a/drivers/base/class.c +++ b/drivers/base/class.c @@ -320,6 +320,7 @@ void class_dev_iter_init(struct class_dev_iter *iter, const struct class *class, start_knode = &start->p->knode_class; klist_iter_init_node(&sp->klist_devices, &iter->ki, start_knode); iter->type = type; + iter->sp = sp; } EXPORT_SYMBOL_GPL(class_dev_iter_init); @@ -361,6 +362,7 @@ EXPORT_SYMBOL_GPL(class_dev_iter_next); void class_dev_iter_exit(struct class_dev_iter *iter) { klist_iter_exit(&iter->ki); + subsys_put(iter->sp); } EXPORT_SYMBOL_GPL(class_dev_iter_exit); diff --git a/include/linux/device/class.h b/include/linux/device/class.h index 9deeaeb457bba..abf3d3bfb6fe4 100644 --- a/include/linux/device/class.h +++ b/include/linux/device/class.h @@ -74,6 +74,7 @@ struct class { struct class_dev_iter { struct klist_iter ki; const struct device_type *type; + struct subsys_private *sp; }; int __must_check class_register(const struct class *class); -- cgit v1.2.3