sysfs: Add sysfs_add/remove_files utility functions

Adding/Removing a whole array of attributes is very common. Add a standard
utility function to do this with a simple function call, instead of
requiring drivers to open code this.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

fs/sysfs/file.c

@@ -542,6 +542,18 @@ int sysfs_create_file(struct kobject * kobj, const struct attribute * attr)
 
 }
 
+int sysfs_create_files(struct kobject *kobj, const struct attribute **ptr)
+{
+	int err = 0;
+	int i;
+
+	for (i = 0; ptr[i] && !err; i++)
+		err = sysfs_create_file(kobj, ptr[i]);
+	if (err)
+		while (--i >= 0)
+			sysfs_remove_file(kobj, ptr[i]);
+	return err;
+}
 
 /**
  * sysfs_add_file_to_group - add an attribute file to a pre-existing group.
@@ -614,6 +626,12 @@ void sysfs_remove_file(struct kobject * kobj, const struct attribute * attr)
 	sysfs_hash_and_remove(kobj->sd, attr->name);
 }
 
+void sysfs_remove_files(struct kobject * kobj, const struct attribute **ptr)
+{
+	int i;
+	for (i = 0; ptr[i]; i++)
+		sysfs_remove_file(kobj, ptr[i]);
+}
 
 /**
  * sysfs_remove_file_from_group - remove an attribute file from a group.
@@ -732,3 +750,5 @@ EXPORT_SYMBOL_GPL(sysfs_schedule_callback);
 
 EXPORT_SYMBOL_GPL(sysfs_create_file);
 EXPORT_SYMBOL_GPL(sysfs_remove_file);
+EXPORT_SYMBOL_GPL(sysfs_remove_files);
+EXPORT_SYMBOL_GPL(sysfs_create_files);

include/linux/sysfs.h

@@ -94,9 +94,12 @@ int __must_check sysfs_move_dir(struct kobject *kobj,
 
 int __must_check sysfs_create_file(struct kobject *kobj,
 				   const struct attribute *attr);
+int __must_check sysfs_create_files(struct kobject *kobj,
+				   const struct attribute **attr);
 int __must_check sysfs_chmod_file(struct kobject *kobj, struct attribute *attr,
 				  mode_t mode);
 void sysfs_remove_file(struct kobject *kobj, const struct attribute *attr);
+void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
 
 int __must_check sysfs_create_bin_file(struct kobject *kobj,
 				       const struct bin_attribute *attr);
@@ -164,6 +167,12 @@ static inline int sysfs_create_file(struct kobject *kobj,
 	return 0;
 }
 
+static inline int sysfs_create_files(struct kobject *kobj,
+				    const struct attribute **attr)
+{
+	return 0;
+}
+
 static inline int sysfs_chmod_file(struct kobject *kobj,
 				   struct attribute *attr, mode_t mode)
 {
@@ -175,6 +184,11 @@ static inline void sysfs_remove_file(struct kobject *kobj,
 {
 }
 
+static inline void sysfs_remove_files(struct kobject *kobj,
+				     const struct attribute **attr)
+{
+}
+
 static inline int sysfs_create_bin_file(struct kobject *kobj,
 					const struct bin_attribute *attr)
 {