xfs: add a ri_entry helper

Add a helper to translate from the item list head to the
rmap_intent_item structure and use it so shorten assignments
and avoid the need for extra local variables.

Signed-off-by: Christoph Hellwig <[email protected]>
Reviewed-by: Darrick J. Wong <[email protected]>
Signed-off-by: Darrick J. Wong <[email protected]>

Author: Christoph Hellwig

fs/xfs/xfs_rmap_item.c

@@ -226,18 +226,20 @@ static const struct xfs_item_ops xfs_rud_item_ops = {
 	.iop_intent	= xfs_rud_item_intent,
 };
 
+static inline struct xfs_rmap_intent *ri_entry(const struct list_head *e)
+{
+	return list_entry(e, struct xfs_rmap_intent, ri_list);
+}
+
 /* Sort rmap intents by AG. */
 static int
 xfs_rmap_update_diff_items(
 	void				*priv,
 	const struct list_head		*a,
 	const struct list_head		*b)
 {
-	struct xfs_rmap_intent		*ra;
-	struct xfs_rmap_intent		*rb;
-
-	ra = container_of(a, struct xfs_rmap_intent, ri_list);
-	rb = container_of(b, struct xfs_rmap_intent, ri_list);
+	struct xfs_rmap_intent		*ra = ri_entry(a);
+	struct xfs_rmap_intent		*rb = ri_entry(b);
 
 	return ra->ri_pag->pag_agno - rb->ri_pag->pag_agno;
 }
@@ -364,11 +366,9 @@ xfs_rmap_update_finish_item(
 	struct list_head		*item,
 	struct xfs_btree_cur		**state)
 {
-	struct xfs_rmap_intent		*ri;
+	struct xfs_rmap_intent		*ri = ri_entry(item);
 	int				error;
 
-	ri = container_of(item, struct xfs_rmap_intent, ri_list);
-
 	error = xfs_rmap_finish_one(tp, ri, state);
 
 	xfs_rmap_update_put_group(ri);
@@ -389,9 +389,7 @@ STATIC void
 xfs_rmap_update_cancel_item(
 	struct list_head		*item)
 {
-	struct xfs_rmap_intent		*ri;
-
-	ri = container_of(item, struct xfs_rmap_intent, ri_list);
+	struct xfs_rmap_intent		*ri = ri_entry(item);
 
 	xfs_rmap_update_put_group(ri);
 	kmem_cache_free(xfs_rmap_intent_cache, ri);