1 files changed, 35 insertions, 0 deletions

diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index e0ac85949067..539e7b5e3f86 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -202,6 +202,7 @@ BTRFS_FEAT_ATTR_INCOMPAT(extended_iref, EXTENDED_IREF);
 BTRFS_FEAT_ATTR_INCOMPAT(raid56, RAID56);
 BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
 BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
+BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
 
 static struct attribute *btrfs_supported_feature_attrs[] = {
         BTRFS_FEAT_ATTR_PTR(mixed_backref),
@@ -213,6 +214,7 @@ static struct attribute *btrfs_supported_feature_attrs[] = {
         BTRFS_FEAT_ATTR_PTR(raid56),
         BTRFS_FEAT_ATTR_PTR(skinny_metadata),
         BTRFS_FEAT_ATTR_PTR(no_holes),
+        BTRFS_FEAT_ATTR_PTR(free_space_tree),
         NULL
 };
 
@@ -780,6 +782,39 @@ failure:
         return error;
 }
 
+
+/*
+ * Change per-fs features in /sys/fs/btrfs/UUID/features to match current
+ * values in superblock. Call after any changes to incompat/compat_ro flags
+ */
+void btrfs_sysfs_feature_update(struct btrfs_fs_info *fs_info,
+                u64 bit, enum btrfs_feature_set set)
+{
+        struct btrfs_fs_devices *fs_devs;
+        struct kobject *fsid_kobj;
+        u64 features;
+        int ret;
+
+        if (!fs_info)
+                return;
+
+        features = get_features(fs_info, set);
+        ASSERT(bit & supported_feature_masks[set]);
+
+        fs_devs = fs_info->fs_devices;
+        fsid_kobj = &fs_devs->fsid_kobj;
+
+        if (!fsid_kobj->state_initialized)
+                return;
+
+        /*
+         * FIXME: this is too heavy to update just one value, ideally we'd like
+         * to use sysfs_update_group but some refactoring is needed first.
+         */
+        sysfs_remove_group(fsid_kobj, &btrfs_feature_attr_group);
+        ret = sysfs_create_group(fsid_kobj, &btrfs_feature_attr_group);
+}
+
 static int btrfs_init_debugfs(void)
 {
 #ifdef CONFIG_DEBUG_FS