debugfs: remove return value of debugfs_create_u8()

No one checks the return value of debugfs_create_u8(), as it's not
needed, so make the return value void, so that no one tries to do so in
the future.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20191011132931.1186197-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/filesystems/debugfs.txt

@@ -68,8 +68,8 @@ actually necessary; the debugfs code provides a number of helper functions
 for simple situations.  Files containing a single integer value can be
 created with any of:
 
-    struct dentry *debugfs_create_u8(const char *name, umode_t mode,
-				     struct dentry *parent, u8 *value);
+    void debugfs_create_u8(const char *name, umode_t mode,
+			   struct dentry *parent, u8 *value);
     struct dentry *debugfs_create_u16(const char *name, umode_t mode,
 				      struct dentry *parent, u16 *value);
     struct dentry *debugfs_create_u32(const char *name, umode_t mode,

fs/debugfs/file.c

@@ -420,20 +420,11 @@ DEFINE_DEBUGFS_ATTRIBUTE(fops_u8_wo, NULL, debugfs_u8_set, "%llu\n");
  * This function creates a file in debugfs with the given name that
  * contains the value of the variable @value.  If the @mode variable is so
  * set, it can be read from, and written to.
- *
- * This function will return a pointer to a dentry if it succeeds.  This
- * pointer must be passed to the debugfs_remove() function when the file is
- * to be removed (no automatic cleanup happens if your module is unloaded,
- * you are responsible here.)  If an error occurs, %ERR_PTR(-ERROR) will be
- * returned.
- *
- * If debugfs is not enabled in the kernel, the value %ERR_PTR(-ENODEV) will
- * be returned.
  */
-struct dentry *debugfs_create_u8(const char *name, umode_t mode,
-				 struct dentry *parent, u8 *value)
+void debugfs_create_u8(const char *name, umode_t mode, struct dentry *parent,
+		       u8 *value)
 {
-	return debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u8,
+	debugfs_create_mode_unsafe(name, mode, parent, value, &fops_u8,
 				   &fops_u8_ro, &fops_u8_wo);
 }
 EXPORT_SYMBOL_GPL(debugfs_create_u8);

include/linux/debugfs.h

@@ -97,8 +97,8 @@ ssize_t debugfs_attr_write(struct file *file, const char __user *buf,
 struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry,
                 struct dentry *new_dir, const char *new_name);
 
-struct dentry *debugfs_create_u8(const char *name, umode_t mode,
-				 struct dentry *parent, u8 *value);
+void debugfs_create_u8(const char *name, umode_t mode, struct dentry *parent,
+		       u8 *value);
 struct dentry *debugfs_create_u16(const char *name, umode_t mode,
 				  struct dentry *parent, u16 *value);
 struct dentry *debugfs_create_u32(const char *name, umode_t mode,
@@ -244,12 +244,8 @@ static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentr
 	return ERR_PTR(-ENODEV);
 }
 
-static inline struct dentry *debugfs_create_u8(const char *name, umode_t mode,
-					       struct dentry *parent,
-					       u8 *value)
-{
-	return ERR_PTR(-ENODEV);
-}
+static inline void debugfs_create_u8(const char *name, umode_t mode,
+				     struct dentry *parent, u8 *value) { }
 
 static inline struct dentry *debugfs_create_u16(const char *name, umode_t mode,
 						struct dentry *parent,