2 files changed, 52 insertions, 2 deletions

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 1ad8c93c1b85..07c1b4ec00df 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -488,17 +488,56 @@ const struct file_operations sysfs_file_operations = {
 	.poll		= sysfs_poll,
 };
 
+int sysfs_attr_ns(struct kobject *kobj, const struct attribute *attr,
+		  const void **pns)
+{
+	struct sysfs_dirent *dir_sd = kobj->sd;
+	const struct sysfs_ops *ops;
+	const void *ns = NULL;
+	int err;
+
+	err = 0;
+	if (!sysfs_ns_type(dir_sd))
+		goto out;
+
+	err = -EINVAL;
+	if (!kobj->ktype)
+		goto out;
+	ops = kobj->ktype->sysfs_ops;
+	if (!ops)
+		goto out;
+	if (!ops->namespace)
+		goto out;
+
+	err = 0;
+	ns = ops->namespace(kobj, attr);
+out:
+	if (err) {
+		WARN(1, KERN_ERR "missing sysfs namespace attribute operation for "
+		     "kobject: %s\n", kobject_name(kobj));
+	}
+	*pns = ns;
+	return err;
+}
+
 int sysfs_add_file_mode(struct sysfs_dirent *dir_sd,
 			const struct attribute *attr, int type, mode_t amode)
 {
 	umode_t mode = (amode & S_IALLUGO) | S_IFREG;
 	struct sysfs_addrm_cxt acxt;
 	struct sysfs_dirent *sd;
+	const void *ns;
 	int rc;
 
+	rc = sysfs_attr_ns(dir_sd->s_dir.kobj, attr, &ns);
+	if (rc)
+		return rc;
+
 	sd = sysfs_new_dirent(attr->name, mode, type);
 	if (!sd)
 		return -ENOMEM;
+
+	sd->s_ns = ns;
 	sd->s_attr.attr = (void *)attr;
 	sysfs_dirent_init_lockdep(sd);
 
@@ -586,12 +625,17 @@ int sysfs_chmod_file(struct kobject *kobj, const struct attribute *attr,
 {
 	struct sysfs_dirent *sd;
 	struct iattr newattrs;
+	const void *ns;
 	int rc;
 
+	rc = sysfs_attr_ns(kobj, attr, &ns);
+	if (rc)
+		return rc;
+
 	mutex_lock(&sysfs_mutex);
 
 	rc = -ENOENT;
-	sd = sysfs_find_dirent(kobj->sd, NULL, attr->name);
+	sd = sysfs_find_dirent(kobj->sd, ns, attr->name);
 	if (!sd)
 		goto out;
 
@@ -616,7 +660,12 @@ EXPORT_SYMBOL_GPL(sysfs_chmod_file);
 
 void sysfs_remove_file(struct kobject * kobj, const struct attribute * attr)
 {
-	sysfs_hash_and_remove(kobj->sd, NULL, attr->name);
+	const void *ns;
+
+	if (sysfs_attr_ns(kobj, attr, &ns))
+		return;
+
+	sysfs_hash_and_remove(kobj->sd, ns, attr->name);
 }
 
 void sysfs_remove_files(struct kobject * kobj, const struct attribute **ptr)
diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h
index d7d2f2158142..dac0859e6440 100644
--- a/include/linux/sysfs.h
+++ b/include/linux/sysfs.h
@@ -112,6 +112,7 @@ struct bin_attribute {
 struct sysfs_ops {
 	ssize_t	(*show)(struct kobject *, struct attribute *,char *);
 	ssize_t	(*store)(struct kobject *,struct attribute *,const char *, size_t);
+	const void *(*namespace)(struct kobject *, const struct attribute *);
 };
 
 struct sysfs_dirent;