fs/jffs2: use rbtree postorder iteration helper instead of opencoding

Use rbtree_postorder_for_each_entry_safe() to destroy the rbtree instead
of opencoding an alternate postorder iteration that modifies the tree

Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 5 insertions, 49 deletions

diff --git a/fs/jffs2/nodelist.c b/fs/jffs2/nodelist.c
index 975a1f562c10..9a5449bc3afb 100644
--- a/fs/jffs2/nodelist.c
+++ b/fs/jffs2/nodelist.c
@@ -564,25 +564,10 @@ struct jffs2_node_frag *jffs2_lookup_node_frag(struct rb_root *fragtree, uint32_
    they're killed. */
 void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c)
 {
-        struct jffs2_node_frag *frag;
-        struct jffs2_node_frag *parent;
-
-        if (!root->rb_node)
-                return;
+        struct jffs2_node_frag *frag, *next;
 
         dbg_fragtree("killing\n");
-
-        frag = (rb_entry(root->rb_node, struct jffs2_node_frag, rb));
-        while(frag) {
-                if (frag->rb.rb_left) {
-                        frag = frag_left(frag);
-                        continue;
-                }
-                if (frag->rb.rb_right) {
-                        frag = frag_right(frag);
-                        continue;
-                }
-
+        rbtree_postorder_for_each_entry_safe(frag, next, root, rb) {
                 if (frag->node && !(--frag->node->frags)) {
                         /* Not a hole, and it's the final remaining frag
                            of this node. Free the node */
@@ -591,17 +576,8 @@ void jffs2_kill_fragtree(struct rb_root *root, struct jffs2_sb_info *c)
 
                         jffs2_free_full_dnode(frag->node);
                 }
-                parent = frag_parent(frag);
-                if (parent) {
-                        if (frag_left(parent) == frag)
-                                parent->rb.rb_left = NULL;
-                        else
-                                parent->rb.rb_right = NULL;
-                }
 
                 jffs2_free_node_frag(frag);
-                frag = parent;
-
                 cond_resched();
         }
 }
diff --git a/fs/jffs2/readinode.c b/fs/jffs2/readinode.c
index ae81b01e6fd7..386303dca382 100644
--- a/fs/jffs2/readinode.c
+++ b/fs/jffs2/readinode.c
@@ -543,33 +543,13 @@ static int jffs2_build_inode_fragtree(struct jffs2_sb_info *c,
 
 static void jffs2_free_tmp_dnode_info_list(struct rb_root *list)
 {
-        struct rb_node *this;
-        struct jffs2_tmp_dnode_info *tn;
-
-        this = list->rb_node;
+        struct jffs2_tmp_dnode_info *tn, *next;
 
-        /* Now at bottom of tree */
-        while (this) {
-                if (this->rb_left)
-                        this = this->rb_left;
-                else if (this->rb_right)
-                        this = this->rb_right;
-                else {
-                        tn = rb_entry(this, struct jffs2_tmp_dnode_info, rb);
+        rbtree_postorder_for_each_entry_safe(tn, next, list, rb) {
                         jffs2_free_full_dnode(tn->fn);
                         jffs2_free_tmp_dnode_info(tn);
-
-                        this = rb_parent(this);
-                        if (!this)
-                                break;
-
-                        if (this->rb_left == &tn->rb)
-                                this->rb_left = NULL;
-                        else if (this->rb_right == &tn->rb)
-                                this->rb_right = NULL;
-                        else BUG();
-                }
         }
+
         *list = RB_ROOT;
 }