[PATCH] btrfs-progs: hide block group tree behind experimental feature

[Qu Wenruo <wqu@suse.com>]

The block group tree doesn't yet have full bi-directional conversion
support from btrfstune, and it seems we may want one or two release
cycles to rule out some extra bugs before really releasing the progs
support.

This patch will hide the block group tree feature behind experimental
flag for the following tools:

- btrfstune
  "-b" option to convert to bg tree.

- mkfs.btrfs
  hide "block-group-tree" feature from both -O (the new default position
  for all features) and -R (the old, soon to be deprecated one).

Signed-off-by: Qu Wenruo <wqu@suse.com>
---
 btrfstune.c         | 4 ++++
 common/fsfeatures.c | 4 +++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/btrfstune.c b/btrfstune.c
index add7b1804400..b9a76ac095f0 100644
--- a/btrfstune.c
+++ b/btrfstune.c
@@ -949,7 +949,11 @@ int BOX_MAIN(btrfstune)(int argc, char *argv[])
 #endif
 			{ NULL, 0, NULL, 0 }
 		};
+#if EXPERIMENTAL
 		int c = getopt_long(argc, argv, "S:rxfuU:nmM:b", long_options, NULL);
+#else
+		int c = getopt_long(argc, argv, "S:rxfuU:nmM:", long_options, NULL);
+#endif
 
 		if (c < 0)
 			break;
diff --git a/common/fsfeatures.c b/common/fsfeatures.c
index 5896f66b3e91..67b5b08befc1 100644
--- a/common/fsfeatures.c
+++ b/common/fsfeatures.c
@@ -224,14 +224,16 @@ static const struct btrfs_feature runtime_features[] = {
 		VERSION_TO_STRING2(safe, 4,9),
 		VERSION_TO_STRING2(default, 5,15),
 		.desc		= "free space tree (space_cache=v2)"
+#if EXPERIMENTAL
 	}, {
 		.name		= "block-group-tree",
 		.flag		= BTRFS_RUNTIME_FEATURE_BLOCK_GROUP_TREE,
 		.sysfs_name = "block_group_tree",
-		VERSION_TO_STRING2(compat, 6,0),
+		VERSION_TO_STRING2(compat, 6,2),
 		VERSION_NULL(safe),
 		VERSION_NULL(default),
 		.desc		= "block group tree to reduce mount time"
+#endif
 	},
 	/* Keep this one last */
 	{
-- 
2.37.3