From akpm@osdl.org Tue Dec 19 22:30:14 2006 Message-Id: <200612192101.kBJL1S44010273@shell0.pdx.osdl.net> Subject: kobject: kobject_uevent() returns manageable value From: "Aneesh Kumar K.V" To: greg@kroah.com Cc: akpm@osdl.org, aneesh.kumar@gmail.com, mauriciolin@gmail.com, randy.dunlap@oracle.com Date: Tue, 19 Dec 2006 13:01:27 -0800 From: "Aneesh Kumar K.V" Since kobject_uevent() function does not return an integer value to indicate if its operation was completed with success or not, it is worth changing it in order to report a proper status (success or error) instead of returning void. [randy.dunlap@oracle.com: Fix inline kobject functions] Cc: Mauricio Lin Signed-off-by: Aneesh Kumar K.V Signed-off-by: Randy Dunlap Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- include/linux/kobject.h | 11 ++++++----- lib/kobject_uevent.c | 44 ++++++++++++++++++++++++++++++-------------- 2 files changed, 36 insertions(+), 19 deletions(-) --- gregkh-2.6.orig/include/linux/kobject.h +++ gregkh-2.6/include/linux/kobject.h @@ -265,8 +265,8 @@ extern int __must_check subsys_create_fi struct subsys_attribute *); #if defined(CONFIG_HOTPLUG) -void kobject_uevent(struct kobject *kobj, enum kobject_action action); -void kobject_uevent_env(struct kobject *kobj, enum kobject_action action, +int kobject_uevent(struct kobject *kobj, enum kobject_action action); +int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, char *envp[]); int add_uevent_var(char **envp, int num_envp, int *cur_index, @@ -274,11 +274,12 @@ int add_uevent_var(char **envp, int num_ const char *format, ...) __attribute__((format (printf, 7, 8))); #else -static inline void kobject_uevent(struct kobject *kobj, enum kobject_action action) { } -static inline void kobject_uevent_env(struct kobject *kobj, +static inline int kobject_uevent(struct kobject *kobj, enum kobject_action action) +{ return 0; } +static inline int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, char *envp[]) -{ } +{ return 0; } static inline int add_uevent_var(char **envp, int num_envp, int *cur_index, char *buffer, int buffer_size, int *cur_len, --- gregkh-2.6.orig/lib/kobject_uevent.c +++ gregkh-2.6/lib/kobject_uevent.c @@ -63,8 +63,11 @@ static char *action_to_string(enum kobje * @action: action that is happening (usually KOBJ_MOVE) * @kobj: struct kobject that the action is happening to * @envp_ext: pointer to environmental data + * + * Returns 0 if kobject_uevent() is completed with success or the + * corresponding error when it fails. */ -void kobject_uevent_env(struct kobject *kobj, enum kobject_action action, +int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, char *envp_ext[]) { char **envp; @@ -79,14 +82,16 @@ void kobject_uevent_env(struct kobject * u64 seq; char *seq_buff; int i = 0; - int retval; + int retval = 0; int j; pr_debug("%s\n", __FUNCTION__); action_string = action_to_string(action); - if (!action_string) - return; + if (!action_string) { + pr_debug("kobject attempted to send uevent without action_string!\n"); + return -EINVAL; + } /* search the kset we belong to */ top_kobj = kobj; @@ -95,31 +100,39 @@ void kobject_uevent_env(struct kobject * top_kobj = top_kobj->parent; } while (!top_kobj->kset && top_kobj->parent); } - if (!top_kobj->kset) - return; + if (!top_kobj->kset) { + pr_debug("kobject attempted to send uevent without kset!\n"); + return -EINVAL; + } kset = top_kobj->kset; uevent_ops = kset->uevent_ops; /* skip the event, if the filter returns zero. */ if (uevent_ops && uevent_ops->filter) - if (!uevent_ops->filter(kset, kobj)) - return; + if (!uevent_ops->filter(kset, kobj)) { + pr_debug("kobject filter function caused the event to drop!\n"); + return 0; + } /* environment index */ envp = kzalloc(NUM_ENVP * sizeof (char *), GFP_KERNEL); if (!envp) - return; + return -ENOMEM; /* environment values */ buffer = kmalloc(BUFFER_SIZE, GFP_KERNEL); - if (!buffer) + if (!buffer) { + retval = -ENOMEM; goto exit; + } /* complete object path */ devpath = kobject_get_path(kobj, GFP_KERNEL); - if (!devpath) + if (!devpath) { + retval = -ENOENT; goto exit; + } /* originating subsystem */ if (uevent_ops && uevent_ops->name) @@ -204,7 +217,7 @@ exit: kfree(devpath); kfree(buffer); kfree(envp); - return; + return retval; } EXPORT_SYMBOL_GPL(kobject_uevent_env); @@ -214,10 +227,13 @@ EXPORT_SYMBOL_GPL(kobject_uevent_env); * * @action: action that is happening (usually KOBJ_ADD and KOBJ_REMOVE) * @kobj: struct kobject that the action is happening to + * + * Returns 0 if kobject_uevent() is completed with success or the + * corresponding error when it fails. */ -void kobject_uevent(struct kobject *kobj, enum kobject_action action) +int kobject_uevent(struct kobject *kobj, enum kobject_action action) { - kobject_uevent_env(kobj, action, NULL); + return kobject_uevent_env(kobj, action, NULL); } EXPORT_SYMBOL_GPL(kobject_uevent);