xfs: vectorise directory leaf operations

Next step in the vectorisation process is the leaf block
encode/decode operations. Most of the operations on leaves are
handled by the data block vectors, so there are relatively few of
them here.

Because of all the shuffling of code and having to pass more state
to some functions, this patch doesn't directly reduce the size of
the binary. It does open up many more opportunities for factoring
and optimisation, however.

   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

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ben Myers <bpm@sgi.com>

1 files changed, 75 insertions, 0 deletions

diff --git a/fs/xfs/xfs_da_format.c b/fs/xfs/xfs_da_format.c
index 1e92a241fd52..ff8b50368c94 100644
--- a/fs/xfs/xfs_da_format.c
+++ b/fs/xfs/xfs_da_format.c
@@ -435,6 +435,48 @@ xfs_dir3_data_unused_p(struct xfs_dir2_data_hdr *hdr)
 		((char *)hdr + xfs_dir3_data_entry_offset());
 }
 
+
+/*
+ * Directory Leaf block operations
+ */
+static int
+xfs_dir2_leaf_hdr_size(void)
+{
+	return sizeof(struct xfs_dir2_leaf_hdr);
+}
+
+static int
+xfs_dir2_max_leaf_ents(struct xfs_mount *mp)
+{
+	return (mp->m_dirblksize - xfs_dir2_leaf_hdr_size()) /
+		(uint)sizeof(struct xfs_dir2_leaf_entry);
+}
+
+static struct xfs_dir2_leaf_entry *
+xfs_dir2_leaf_ents_p(struct xfs_dir2_leaf *lp)
+{
+	return lp->__ents;
+}
+
+static int
+xfs_dir3_leaf_hdr_size(void)
+{
+	return sizeof(struct xfs_dir3_leaf_hdr);
+}
+
+static inline int
+xfs_dir3_max_leaf_ents(struct xfs_mount *mp)
+{
+	return (mp->m_dirblksize - xfs_dir3_leaf_hdr_size()) /
+		(uint)sizeof(struct xfs_dir2_leaf_entry);
+}
+
+static inline struct xfs_dir2_leaf_entry *
+xfs_dir3_leaf_ents_p(struct xfs_dir2_leaf *lp)
+{
+	return ((struct xfs_dir3_leaf *)lp)->__ents;
+}
+
 const struct xfs_dir_ops xfs_dir2_ops = {
 	.sf_entsize = xfs_dir2_sf_entsize,
 	.sf_nextentry = xfs_dir2_sf_nextentry,
@@ -462,6 +504,10 @@ const struct xfs_dir_ops xfs_dir2_ops = {
 	.data_entry_p = xfs_dir2_data_entry_p,
 	.data_unused_p = xfs_dir2_data_unused_p,
 
+	.leaf_hdr_size = xfs_dir2_leaf_hdr_size,
+	.leaf_max_ents = xfs_dir2_max_leaf_ents,
+	.leaf_ents_p = xfs_dir2_leaf_ents_p,
+
 };
 
 const struct xfs_dir_ops xfs_dir2_ftype_ops = {
@@ -490,6 +536,10 @@ const struct xfs_dir_ops xfs_dir2_ftype_ops = {
 	.data_first_entry_p = xfs_dir2_data_first_entry_p,
 	.data_entry_p = xfs_dir2_data_entry_p,
 	.data_unused_p = xfs_dir2_data_unused_p,
+
+	.leaf_hdr_size = xfs_dir2_leaf_hdr_size,
+	.leaf_max_ents = xfs_dir2_max_leaf_ents,
+	.leaf_ents_p = xfs_dir2_leaf_ents_p,
 };
 
 const struct xfs_dir_ops xfs_dir3_ops = {
@@ -518,4 +568,29 @@ const struct xfs_dir_ops xfs_dir3_ops = {
 	.data_first_entry_p = xfs_dir3_data_first_entry_p,
 	.data_entry_p = xfs_dir3_data_entry_p,
 	.data_unused_p = xfs_dir3_data_unused_p,
+
+	.leaf_hdr_size = xfs_dir3_leaf_hdr_size,
+	.leaf_max_ents = xfs_dir3_max_leaf_ents,
+	.leaf_ents_p = xfs_dir3_leaf_ents_p,
 };
+
+/*
+ * Return the ops structure according to the current config.  If we are passed
+ * an inode, then that overrides the default config we use which is based on
+ * feature bits.
+ */
+const struct xfs_dir_ops *
+xfs_dir_get_ops(
+	struct xfs_mount	*mp,
+	struct xfs_inode	*dp)
+{
+	if (dp)
+		return dp->d_ops;
+	if (mp->m_dir_inode_ops)
+		return mp->m_dir_inode_ops;
+	if (xfs_sb_version_hascrc(&mp->m_sb))
+		return &xfs_dir3_ops;
+	if (xfs_sb_version_hasftype(&mp->m_sb))
+		return &xfs_dir2_ftype_ops;
+	return &xfs_dir2_ops;
+}