ocfs2: Store dir index records inline

Allow us to store a small number of directory index records in the
ocfs2_dx_root_block. This saves us a disk read on small to medium sized
directories (less than about 250 entries). The inline root is automatically
turned into a root block with extents if the directory size increases beyond
it's capacity.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <joel.becker@oracle.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/fs/ocfs2/journal.h b/fs/ocfs2/journal.h
index 4939c04290ca..5585dde91344 100644
--- a/fs/ocfs2/journal.h
+++ b/fs/ocfs2/journal.h
@@ -458,6 +458,16 @@ static inline int ocfs2_rename_credits(struct super_block *sb)
 #define OCFS2_DX_ROOT_REMOVE_CREDITS (OCFS2_INODE_UPDATE_CREDITS +      \
                                       OCFS2_SUBALLOC_FREE)
 
+static inline int ocfs2_calc_dxi_expand_credits(struct super_block *sb)
+{
+        int credits = 1 + OCFS2_SUBALLOC_ALLOC;
+
+        credits += ocfs2_clusters_to_blocks(sb, 1);
+        credits += ocfs2_quota_trans_credits(sb);
+
+        return credits;
+}
+
 /*
  * Please note that the caller must make sure that root_el is the root
  * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise