[Btrfs-devel] [PATCH 1/2] add root item block accounting to btrfs

[Josef Bacik]

Hello,

This patch adds used block accounting to root items in btrfs.  I basically just
copied what we do for super blocks, I assume this is right, I don't really have
a way to check it (at least I don't think I do).  Ran various tests on the FS
with these two patches and no issues.  Thanks much,

Josef

diff -r f6da57af2473 ctree.h
--- a/ctree.h	Wed Aug 08 20:17:12 2007 -0400
+++ b/ctree.h	Fri Aug 10 14:08:46 2007 -0400
@@ -811,6 +811,17 @@ static inline void btrfs_set_root_flags(
 static inline void btrfs_set_root_flags(struct btrfs_root_item *item, u32 val)
 {
 	item->flags = cpu_to_le32(val);
+}
+
+static inline void btrfs_set_root_blocks_used(struct btrfs_root_item *r,
+						   u64 val)
+{
+	r->blocks_used = cpu_to_le64(val);
+}
+
+static inline u64 btrfs_root_blocks_used(struct btrfs_root_item *r)
+{
+	return le64_to_cpu(r->blocks_used);
 }
 
 static inline u64 btrfs_super_blocknr(struct btrfs_super_block *s)
diff -r f6da57af2473 extent-tree.c
--- a/extent-tree.c	Wed Aug 08 20:17:12 2007 -0400
+++ b/extent-tree.c	Fri Aug 10 14:40:08 2007 -0400
@@ -852,16 +852,23 @@ static int __free_extent(struct btrfs_tr
 	btrfs_set_extent_refs(ei, refs);
 	btrfs_mark_buffer_dirty(path->nodes[0]);
 	if (refs == 0) {
-		u64 super_blocks_used;
+		u64 super_blocks_used, root_blocks_used;
 
 		if (pin) {
 			ret = pin_down_block(root, blocknr, 0);
 			BUG_ON(ret);
 		}
 
+		/* block accounting for super block */
 		super_blocks_used = btrfs_super_blocks_used(&info->super_copy);
 		btrfs_set_super_blocks_used(&info->super_copy,
 					    super_blocks_used - num_blocks);
+
+		/* block accounting for root item */
+		root_blocks_used = btrfs_root_blocks_used(&root->root_item);
+		btrfs_set_root_blocks_used(&root->root_item, 
+					   root_blocks_used - num_blocks);
+
 		ret = btrfs_del_item(trans, extent_root, path);
 		if (ret) {
 			return ret;
@@ -1175,7 +1182,7 @@ int btrfs_alloc_extent(struct btrfs_tran
 {
 	int ret;
 	int pending_ret;
-	u64 super_blocks_used;
+	u64 super_blocks_used, root_blocks_used;
 	u64 search_start = 0;
 	struct btrfs_fs_info *info = root->fs_info;
 	struct btrfs_root *extent_root = info->extent_root;
@@ -1193,9 +1200,15 @@ int btrfs_alloc_extent(struct btrfs_tran
 	if (ret)
 		return ret;
 
+	/* block accounting for super block */
 	super_blocks_used = btrfs_super_blocks_used(&info->super_copy);
 	btrfs_set_super_blocks_used(&info->super_copy, super_blocks_used +
 				    num_blocks);
+	
+	/* block accounting for root item */
+	root_blocks_used = btrfs_root_blocks_used(&root->root_item);
+	btrfs_set_root_blocks_used(&root->root_item, root_blocks_used +
+				   num_blocks);
 
 	if (root == extent_root) {
 		BUG_ON(num_blocks != 1);
diff -r f6da57af2473 inode.c
--- a/inode.c	Wed Aug 08 20:17:12 2007 -0400
+++ b/inode.c	Fri Aug 10 14:26:37 2007 -0400
@@ -2021,6 +2021,7 @@ static int create_subvol(struct btrfs_ro
 
 	btrfs_set_root_blocknr(&root_item, bh_blocknr(subvol));
 	btrfs_set_root_refs(&root_item, 1);
+	btrfs_set_root_blocks_used(&root_item, 0);
 	memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
 	root_item.drop_level = 0;
 	brelse(subvol);