btrfs: add block reserve for treelog

We need to add a dedicated block_rsv for tree-log, because the block_rsv
serves for a tree node allocation in btrfs_alloc_tree_block(). Currently,
tree-log tree uses fs_info->empty_block_rsv, which is shared across trees
and points to the normal metadata space_info. Instead, we add a dedicated
block_rsv and that block_rsv can use the dedicated sub-space_info.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>

5 files changed, 20 insertions, 2 deletions

diff --git a/fs/btrfs/block-rsv.c b/fs/btrfs/block-rsv.c
index 3f3608299c0b..5ad6de738aee 100644
--- a/fs/btrfs/block-rsv.c
+++ b/fs/btrfs/block-rsv.c
@@ -418,6 +418,9 @@ void btrfs_init_root_block_rsv(struct btrfs_root *root)
 	case BTRFS_CHUNK_TREE_OBJECTID:
 		root->block_rsv = &fs_info->chunk_block_rsv;
 		break;
+	case BTRFS_TREE_LOG_OBJECTID:
+		root->block_rsv = &fs_info->treelog_rsv;
+		break;
 	default:
 		root->block_rsv = NULL;
 		break;
@@ -438,6 +441,14 @@ void btrfs_init_global_block_rsv(struct btrfs_fs_info *fs_info)
 	fs_info->delayed_block_rsv.space_info = space_info;
 	fs_info->delayed_refs_rsv.space_info = space_info;
 
+	/* The treelog_rsv uses a dedicated space_info on the zoned mode. */
+	if (!btrfs_is_zoned(fs_info)) {
+		fs_info->treelog_rsv.space_info = space_info;
+	} else {
+		ASSERT(space_info->sub_group[0]->subgroup_id == BTRFS_SUB_GROUP_TREELOG);
+		fs_info->treelog_rsv.space_info = space_info->sub_group[0];
+	}
+
 	btrfs_update_global_block_rsv(fs_info);
 }
 
diff --git a/fs/btrfs/block-rsv.h b/fs/btrfs/block-rsv.h
index d12b1fac5c74..79ae9d05cd91 100644
--- a/fs/btrfs/block-rsv.h
+++ b/fs/btrfs/block-rsv.h
@@ -24,6 +24,7 @@ enum btrfs_rsv_type {
 	BTRFS_BLOCK_RSV_CHUNK,
 	BTRFS_BLOCK_RSV_DELOPS,
 	BTRFS_BLOCK_RSV_DELREFS,
+	BTRFS_BLOCK_RSV_TREELOG,
 	BTRFS_BLOCK_RSV_EMPTY,
 	BTRFS_BLOCK_RSV_TEMP,
 };
diff --git a/fs/btrfs/delalloc-space.c b/fs/btrfs/delalloc-space.c
index 7128507931f1..288e1776c02d 100644
--- a/fs/btrfs/delalloc-space.c
+++ b/fs/btrfs/delalloc-space.c
@@ -115,8 +115,11 @@ static inline struct btrfs_space_info *data_sinfo_for_inode(const struct btrfs_i
 {
 	struct btrfs_fs_info *fs_info = inode->root->fs_info;
 
-	if (btrfs_is_zoned(fs_info) && btrfs_is_data_reloc_root(inode->root))
-		return fs_info->data_sinfo->sub_group[SUB_GROUP_DATA_RELOC];
+	if (btrfs_is_zoned(fs_info) && btrfs_is_data_reloc_root(inode->root)) {
+		ASSERT(fs_info->data_sinfo->sub_group[0]->subgroup_id ==
+		       BTRFS_SUB_GROUP_DATA_RELOC);
+		return fs_info->data_sinfo->sub_group[0];
+	}
 	return fs_info->data_sinfo;
 }
 
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 308e8f384ecb..5bcf11246ba6 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2831,6 +2831,7 @@ void btrfs_init_fs_info(struct btrfs_fs_info *fs_info)
 			     BTRFS_BLOCK_RSV_GLOBAL);
 	btrfs_init_block_rsv(&fs_info->trans_block_rsv, BTRFS_BLOCK_RSV_TRANS);
 	btrfs_init_block_rsv(&fs_info->chunk_block_rsv, BTRFS_BLOCK_RSV_CHUNK);
+	btrfs_init_block_rsv(&fs_info->treelog_rsv, BTRFS_BLOCK_RSV_TREELOG);
 	btrfs_init_block_rsv(&fs_info->empty_block_rsv, BTRFS_BLOCK_RSV_EMPTY);
 	btrfs_init_block_rsv(&fs_info->delayed_block_rsv,
 			     BTRFS_BLOCK_RSV_DELOPS);
diff --git a/fs/btrfs/fs.h b/fs/btrfs/fs.h
index 007b7c9b3909..4394de12a767 100644
--- a/fs/btrfs/fs.h
+++ b/fs/btrfs/fs.h
@@ -472,6 +472,8 @@ struct btrfs_fs_info {
 	struct btrfs_block_rsv delayed_block_rsv;
 	/* Block reservation for delayed refs */
 	struct btrfs_block_rsv delayed_refs_rsv;
+	/* Block reservation for treelog tree */
+	struct btrfs_block_rsv treelog_rsv;
 
 	struct btrfs_block_rsv empty_block_rsv;