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-rw-r--r--fs/sysfs/file.c95
1 files changed, 2 insertions, 93 deletions
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 1b8b91b67fd..e9ef59b3abb 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -47,12 +47,13 @@ static int sysfs_kf_seq_show(struct seq_file *sf, void *v)
ssize_t count;
char *buf;
- /* acquire buffer and ensure that it's >= PAGE_SIZE */
+ /* acquire buffer and ensure that it's >= PAGE_SIZE and clear */
count = seq_get_buf(sf, &buf);
if (count < PAGE_SIZE) {
seq_commit(sf, -1);
return 0;
}
+ memset(buf, 0, PAGE_SIZE);
/*
* Invoke show(). Control may reach here via seq file lseek even
@@ -453,95 +454,3 @@ void sysfs_remove_bin_file(struct kobject *kobj,
kernfs_remove_by_name(kobj->sd, attr->attr.name);
}
EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);
-
-struct sysfs_schedule_callback_struct {
- struct list_head workq_list;
- struct kobject *kobj;
- void (*func)(void *);
- void *data;
- struct module *owner;
- struct work_struct work;
-};
-
-static struct workqueue_struct *sysfs_workqueue;
-static DEFINE_MUTEX(sysfs_workq_mutex);
-static LIST_HEAD(sysfs_workq);
-static void sysfs_schedule_callback_work(struct work_struct *work)
-{
- struct sysfs_schedule_callback_struct *ss = container_of(work,
- struct sysfs_schedule_callback_struct, work);
-
- (ss->func)(ss->data);
- kobject_put(ss->kobj);
- module_put(ss->owner);
- mutex_lock(&sysfs_workq_mutex);
- list_del(&ss->workq_list);
- mutex_unlock(&sysfs_workq_mutex);
- kfree(ss);
-}
-
-/**
- * sysfs_schedule_callback - helper to schedule a callback for a kobject
- * @kobj: object we're acting for.
- * @func: callback function to invoke later.
- * @data: argument to pass to @func.
- * @owner: module owning the callback code
- *
- * sysfs attribute methods must not unregister themselves or their parent
- * kobject (which would amount to the same thing). Attempts to do so will
- * deadlock, since unregistration is mutually exclusive with driver
- * callbacks.
- *
- * Instead methods can call this routine, which will attempt to allocate
- * and schedule a workqueue request to call back @func with @data as its
- * argument in the workqueue's process context. @kobj will be pinned
- * until @func returns.
- *
- * Returns 0 if the request was submitted, -ENOMEM if storage could not
- * be allocated, -ENODEV if a reference to @owner isn't available,
- * -EAGAIN if a callback has already been scheduled for @kobj.
- */
-int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
- void *data, struct module *owner)
-{
- struct sysfs_schedule_callback_struct *ss, *tmp;
-
- if (!try_module_get(owner))
- return -ENODEV;
-
- mutex_lock(&sysfs_workq_mutex);
- list_for_each_entry_safe(ss, tmp, &sysfs_workq, workq_list)
- if (ss->kobj == kobj) {
- module_put(owner);
- mutex_unlock(&sysfs_workq_mutex);
- return -EAGAIN;
- }
- mutex_unlock(&sysfs_workq_mutex);
-
- if (sysfs_workqueue == NULL) {
- sysfs_workqueue = create_singlethread_workqueue("sysfsd");
- if (sysfs_workqueue == NULL) {
- module_put(owner);
- return -ENOMEM;
- }
- }
-
- ss = kmalloc(sizeof(*ss), GFP_KERNEL);
- if (!ss) {
- module_put(owner);
- return -ENOMEM;
- }
- kobject_get(kobj);
- ss->kobj = kobj;
- ss->func = func;
- ss->data = data;
- ss->owner = owner;
- INIT_WORK(&ss->work, sysfs_schedule_callback_work);
- INIT_LIST_HEAD(&ss->workq_list);
- mutex_lock(&sysfs_workq_mutex);
- list_add_tail(&ss->workq_list, &sysfs_workq);
- mutex_unlock(&sysfs_workq_mutex);
- queue_work(sysfs_workqueue, &ss->work);
- return 0;
-}
-EXPORT_SYMBOL_GPL(sysfs_schedule_callback);