[PATCH v2 09/30] btrfs-progs: common: allow users to select extent-tree-v2 option

[Josef Bacik <josef@toxicpanda.com>]

We want to enable developers to test the extent tree v2 features as they
are added, add the ability to mkfs an extent tree v2 fs if we have
experimental enabled.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
 common/fsfeatures.c   | 11 +++++++++++
 kernel-shared/ctree.h | 18 ++++++++++++++++++
 mkfs/main.c           |  6 ++++++
 3 files changed, 35 insertions(+)

diff --git a/common/fsfeatures.c b/common/fsfeatures.c
index df1bb8f7..23a92c21 100644
--- a/common/fsfeatures.c
+++ b/common/fsfeatures.c
@@ -131,6 +131,17 @@ static const struct btrfs_feature mkfs_features[] = {
 		VERSION_NULL(default),
 		.desc		= "support zoned devices"
 	},
+#endif
+#if EXPERIMENTAL
+	{
+		.name		= "extent-tree-v2",
+		.flag		= BTRFS_FEATURE_INCOMPAT_EXTENT_TREE_V2,
+		.sysfs_name	= "extent_tree_v2",
+		VERSION_TO_STRING2(compat, 5,15),
+		VERSION_NULL(safe),
+		VERSION_NULL(default),
+		.desc		= "new extent tree format"
+	},
 #endif
 	/* Keep this one last */
 	{
diff --git a/kernel-shared/ctree.h b/kernel-shared/ctree.h
index 12a8165d..8a46306e 100644
--- a/kernel-shared/ctree.h
+++ b/kernel-shared/ctree.h
@@ -507,6 +507,23 @@ struct btrfs_super_block {
 	(BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE |	\
 	 BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID)
 
+#if EXPERIMENTAL
+#define BTRFS_FEATURE_INCOMPAT_SUPP			\
+	(BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF |		\
+	 BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL |	\
+	 BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO |		\
+	 BTRFS_FEATURE_INCOMPAT_COMPRESS_ZSTD |		\
+	 BTRFS_FEATURE_INCOMPAT_BIG_METADATA |		\
+	 BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF |		\
+	 BTRFS_FEATURE_INCOMPAT_RAID56 |		\
+	 BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS |		\
+	 BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA |	\
+	 BTRFS_FEATURE_INCOMPAT_NO_HOLES |		\
+	 BTRFS_FEATURE_INCOMPAT_RAID1C34 |		\
+	 BTRFS_FEATURE_INCOMPAT_METADATA_UUID |		\
+	 BTRFS_FEATURE_INCOMPAT_ZONED |			\
+	 BTRFS_FEATURE_INCOMPAT_EXTENT_TREE_V2)
+#else
 #define BTRFS_FEATURE_INCOMPAT_SUPP			\
 	(BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF |		\
 	 BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL |	\
@@ -521,6 +538,7 @@ struct btrfs_super_block {
 	 BTRFS_FEATURE_INCOMPAT_RAID1C34 |		\
 	 BTRFS_FEATURE_INCOMPAT_METADATA_UUID |		\
 	 BTRFS_FEATURE_INCOMPAT_ZONED)
+#endif
 
 /*
  * A leaf is full of items. offset and size tell us where to find
diff --git a/mkfs/main.c b/mkfs/main.c
index d0c863fd..2c4b7b00 100644
--- a/mkfs/main.c
+++ b/mkfs/main.c
@@ -1223,6 +1223,12 @@ int BOX_MAIN(mkfs)(int argc, char **argv)
 		features |= BTRFS_FEATURE_INCOMPAT_RAID1C34;
 	}
 
+	/* Extent tree v2 comes with a set of mandatory features. */
+	if (features & BTRFS_FEATURE_INCOMPAT_EXTENT_TREE_V2) {
+		features |= BTRFS_FEATURE_INCOMPAT_NO_HOLES;
+		runtime_features |= BTRFS_RUNTIME_FEATURE_FREE_SPACE_TREE;
+	}
+
 	if (zoned) {
 		if (source_dir_set) {
 			error("the option -r and zoned mode are incompatible");
-- 
2.26.3