diff mbox series

[3/3] btrfs: separate BLOCK_GROUP_TREE compat RO flag from EXTENT_TREE_V2

Message ID 3ba846068e1205a4c38b39f24174ab6d13edce4f.1657699083.git.wqu@suse.com (mailing list archive)
State New, archived
Headers show
Series btrfs: separate BLOCK_GROUP_TREE feature from extent-tree-v2 | expand

Commit Message

Qu Wenruo July 13, 2022, 8:06 a.m. UTC 
The problem of long mount time caused by block group item search is
already known for over 7 years, and the solution of block group tree is
proposed at least for 5 years.

There is really no need to bound this feature into extent tree v2, just
introduce compat RO flag, BLOCK_GROUP_TREE, to correctly solve the
problem.

All the code handling block group root is already in the upstream
kernel, thus this patch really only needs to introduce the new compat RO
flag.

Signed-off-by: Qu Wenruo <wqu@suse.com>
---
 fs/btrfs/ctree.h           | 3 ++-
 fs/btrfs/disk-io.h         | 2 +-
 fs/btrfs/sysfs.c           | 2 ++
 include/uapi/linux/btrfs.h | 6 ++++++
 4 files changed, 11 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 36efb1f4c9ff..4c15efcc158c 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -310,7 +310,8 @@  static_assert(sizeof(struct btrfs_super_block) == BTRFS_SUPER_INFO_SIZE);
 #define BTRFS_FEATURE_COMPAT_RO_SUPP			\
 	(BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE |	\
 	 BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID | \
-	 BTRFS_FEATURE_COMPAT_RO_VERITY)
+	 BTRFS_FEATURE_COMPAT_RO_VERITY |		\
+	 BTRFS_FEATURE_COMPAT_RO_BLOCK_GROUP_TREE)
 
 #define BTRFS_FEATURE_COMPAT_RO_SAFE_SET	0ULL
 #define BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR	0ULL
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index 8993b428e09c..e7d289b0ed14 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -103,7 +103,7 @@  static inline struct btrfs_root *btrfs_grab_root(struct btrfs_root *root)
 
 static inline struct btrfs_root *btrfs_block_group_root(struct btrfs_fs_info *fs_info)
 {
-	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
+	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE))
 		return fs_info->block_group_root;
 	return btrfs_extent_root(fs_info, 0);
 }
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index d5d0717fd09a..b2eb6d40b21d 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -286,6 +286,7 @@  BTRFS_FEAT_ATTR_INCOMPAT(skinny_metadata, SKINNY_METADATA);
 BTRFS_FEAT_ATTR_INCOMPAT(no_holes, NO_HOLES);
 BTRFS_FEAT_ATTR_INCOMPAT(metadata_uuid, METADATA_UUID);
 BTRFS_FEAT_ATTR_COMPAT_RO(free_space_tree, FREE_SPACE_TREE);
+BTRFS_FEAT_ATTR_COMPAT_RO(block_group_tree, BLOCK_GROUP_TREE);
 BTRFS_FEAT_ATTR_INCOMPAT(raid1c34, RAID1C34);
 #ifdef CONFIG_BLK_DEV_ZONED
 BTRFS_FEAT_ATTR_INCOMPAT(zoned, ZONED);
@@ -316,6 +317,7 @@  static struct attribute *btrfs_supported_feature_attrs[] = {
 	BTRFS_FEAT_ATTR_PTR(no_holes),
 	BTRFS_FEAT_ATTR_PTR(metadata_uuid),
 	BTRFS_FEAT_ATTR_PTR(free_space_tree),
+	BTRFS_FEAT_ATTR_PTR(block_group_tree),
 	BTRFS_FEAT_ATTR_PTR(raid1c34),
 #ifdef CONFIG_BLK_DEV_ZONED
 	BTRFS_FEAT_ATTR_PTR(zoned),
diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h
index f54dc91e4025..5f79610e1c72 100644
--- a/include/uapi/linux/btrfs.h
+++ b/include/uapi/linux/btrfs.h
@@ -290,6 +290,12 @@  struct btrfs_ioctl_fs_info_args {
 #define BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE_VALID	(1ULL << 1)
 #define BTRFS_FEATURE_COMPAT_RO_VERITY			(1ULL << 2)
 
+/*
+ * Put all block group items into a dedicate block group tree, greatly
+ * reduce mount time for large fs.
+ */
+#define BTRFS_FEATURE_COMPAT_RO_BLOCK_GROUP_TREE	(1ULL << 5)
+
 #define BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF	(1ULL << 0)
 #define BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL	(1ULL << 1)
 #define BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS	(1ULL << 2)