xfs: convert directory vector functions to constants

Next step in the vectorisation process is the directory free block
encode/decode operations. There are relatively few of these, though
there are quite a number of calls to them.

Binary sizes:

   text    data     bss     dec     hex filename
 794490   96802    1096  892388   d9de4 fs/xfs/xfs.o.orig
 792986   96802    1096  890884   d9804 fs/xfs/xfs.o.p1
 792350   96802    1096  890248   d9588 fs/xfs/xfs.o.p2
 789293   96802    1096  887191   d8997 fs/xfs/xfs.o.p3
 789005   96802    1096  886903   d8997 fs/xfs/xfs.o.p4
 789061   96802    1096  886959   d88af fs/xfs/xfs.o.p5
 789733   96802    1096  887631   d8b4f fs/xfs/xfs.o.p6
 791421   96802    1096  889319   d91e7 fs/xfs/xfs.o.p7
 791701   96802    1096  889599   d92ff fs/xfs/xfs.o.p8

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

1 files changed, 89 insertions, 0 deletions

diff --git a/fs/xfs/xfs_da_format.c b/fs/xfs/xfs_da_format.c
index b232c275791d..01e6f9a9b804 100644
--- a/fs/xfs/xfs_da_format.c
+++ b/fs/xfs/xfs_da_format.c
@@ -629,6 +629,80 @@ xfs_da3_node_hdr_to_disk(
 /*
  * Directory free space block operations
  */
+static int
+xfs_dir2_free_hdr_size(void)
+{
+	return sizeof(struct xfs_dir2_free_hdr);
+}
+
+static int
+xfs_dir2_free_max_bests(struct xfs_mount *mp)
+{
+	return (mp->m_dirblksize - xfs_dir2_free_hdr_size()) /
+		sizeof(xfs_dir2_data_off_t);
+}
+
+static __be16 *
+xfs_dir2_free_bests_p(struct xfs_dir2_free *free)
+{
+	return (__be16 *)((char *)free + xfs_dir2_free_hdr_size());
+}
+
+/*
+ * Convert data space db to the corresponding free db.
+ */
+static xfs_dir2_db_t
+xfs_dir2_db_to_fdb(struct xfs_mount *mp, xfs_dir2_db_t db)
+{
+	return XFS_DIR2_FREE_FIRSTDB(mp) + db / xfs_dir2_free_max_bests(mp);
+}
+
+/*
+ * Convert data space db to the corresponding index in a free db.
+ */
+static int
+xfs_dir2_db_to_fdindex(struct xfs_mount *mp, xfs_dir2_db_t db)
+{
+	return db % xfs_dir2_free_max_bests(mp);
+}
+
+static int
+xfs_dir3_free_hdr_size(void)
+{
+	return sizeof(struct xfs_dir3_free_hdr);
+}
+
+static int
+xfs_dir3_free_max_bests(struct xfs_mount *mp)
+{
+	return (mp->m_dirblksize - xfs_dir3_free_hdr_size()) /
+		sizeof(xfs_dir2_data_off_t);
+}
+
+static __be16 *
+xfs_dir3_free_bests_p(struct xfs_dir2_free *free)
+{
+	return (__be16 *)((char *)free + xfs_dir3_free_hdr_size());
+}
+
+/*
+ * Convert data space db to the corresponding free db.
+ */
+static xfs_dir2_db_t
+xfs_dir3_db_to_fdb(struct xfs_mount *mp, xfs_dir2_db_t db)
+{
+	return XFS_DIR2_FREE_FIRSTDB(mp) + db / xfs_dir3_free_max_bests(mp);
+}
+
+/*
+ * Convert data space db to the corresponding index in a free db.
+ */
+static int
+xfs_dir3_db_to_fdindex(struct xfs_mount *mp, xfs_dir2_db_t db)
+{
+	return db % xfs_dir3_free_max_bests(mp);
+}
+
 static void
 xfs_dir2_free_hdr_from_disk(
 	struct xfs_dir3_icfree_hdr	*to,
@@ -722,8 +796,13 @@ const struct xfs_dir_ops xfs_dir2_ops = {
 	.node_hdr_from_disk = xfs_da2_node_hdr_from_disk,
 	.node_tree_p = xfs_da2_node_tree_p,
 
+	.free_hdr_size = xfs_dir2_free_hdr_size,
 	.free_hdr_to_disk = xfs_dir2_free_hdr_to_disk,
 	.free_hdr_from_disk = xfs_dir2_free_hdr_from_disk,
+	.free_max_bests = xfs_dir2_free_max_bests,
+	.free_bests_p = xfs_dir2_free_bests_p,
+	.db_to_fdb = xfs_dir2_db_to_fdb,
+	.db_to_fdindex = xfs_dir2_db_to_fdindex,
 };
 
 const struct xfs_dir_ops xfs_dir2_ftype_ops = {
@@ -764,8 +843,13 @@ const struct xfs_dir_ops xfs_dir2_ftype_ops = {
 	.node_hdr_from_disk = xfs_da2_node_hdr_from_disk,
 	.node_tree_p = xfs_da2_node_tree_p,
 
+	.free_hdr_size = xfs_dir2_free_hdr_size,
 	.free_hdr_to_disk = xfs_dir2_free_hdr_to_disk,
 	.free_hdr_from_disk = xfs_dir2_free_hdr_from_disk,
+	.free_max_bests = xfs_dir2_free_max_bests,
+	.free_bests_p = xfs_dir2_free_bests_p,
+	.db_to_fdb = xfs_dir2_db_to_fdb,
+	.db_to_fdindex = xfs_dir2_db_to_fdindex,
 };
 
 const struct xfs_dir_ops xfs_dir3_ops = {
@@ -806,8 +890,13 @@ const struct xfs_dir_ops xfs_dir3_ops = {
 	.node_hdr_from_disk = xfs_da3_node_hdr_from_disk,
 	.node_tree_p = xfs_da3_node_tree_p,
 
+	.free_hdr_size = xfs_dir3_free_hdr_size,
 	.free_hdr_to_disk = xfs_dir3_free_hdr_to_disk,
 	.free_hdr_from_disk = xfs_dir3_free_hdr_from_disk,
+	.free_max_bests = xfs_dir3_free_max_bests,
+	.free_bests_p = xfs_dir3_free_bests_p,
+	.db_to_fdb = xfs_dir3_db_to_fdb,
+	.db_to_fdindex = xfs_dir3_db_to_fdindex,
 };
 
 const struct xfs_dir_ops xfs_dir2_nondir_ops = {