btrfs: publish per-super attributes in sysfs

[deliverable/linux.git] / fs / btrfs / sysfs.c

diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index 9e217b5819039697ccb552f28a8c622eccbeeca0..79be4a187af9e0478f882bda03ef6593125c9a72 100644 (file)
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -28,6 +28,25 @@
 #include "transaction.h"
 #include "sysfs.h"
 
+static void btrfs_release_super_kobj(struct kobject *kobj);
+static struct kobj_type btrfs_ktype = {
+       .sysfs_ops      = &kobj_sysfs_ops,
+       .release        = btrfs_release_super_kobj,
+};
+
+static inline struct btrfs_fs_info *to_fs_info(struct kobject *kobj)
+{
+       if (kobj->ktype != &btrfs_ktype)
+               return NULL;
+       return container_of(kobj, struct btrfs_fs_info, super_kobj);
+}
+
+static void btrfs_release_super_kobj(struct kobject *kobj)
+{
+       struct btrfs_fs_info *fs_info = to_fs_info(kobj);
+       complete(&fs_info->kobj_unregister);
+}
+
 static ssize_t btrfs_feature_attr_show(struct kobject *kobj,
                                       struct kobj_attribute *a, char *buf)
 {
@@ -65,6 +84,23 @@ static const struct attribute_group btrfs_feature_attr_group = {
 /* /sys/fs/btrfs/ entry */
 static struct kset *btrfs_kset;
 
+void btrfs_sysfs_remove_one(struct btrfs_fs_info *fs_info)
+{
+       kobject_del(&fs_info->super_kobj);
+       kobject_put(&fs_info->super_kobj);
+       wait_for_completion(&fs_info->kobj_unregister);
+}
+
+int btrfs_sysfs_add_one(struct btrfs_fs_info *fs_info)
+{
+       int error;
+
+       init_completion(&fs_info->kobj_unregister);
+       error = kobject_init_and_add(&fs_info->super_kobj, &btrfs_ktype, NULL,
+                                    "%pU", fs_info->fsid);
+       return error;
+}
+
 int btrfs_init_sysfs(void)
 {
        int ret;