Merge git://git.infradead.org/~dwmw2/rbtree-2.6

* git://git.infradead.org/~dwmw2/rbtree-2.6:
  [RBTREE] Switch rb_colour() et al to en_US spelling of 'color' for consistency
  Update UML kernel/physmem.c to use rb_parent() accessor macro
  [RBTREE] Update hrtimers to use rb_parent() accessor macro.
  [RBTREE] Add explicit alignment to sizeof(long) for struct rb_node.
  [RBTREE] Merge colour and parent fields of struct rb_node.
  [RBTREE] Remove dead code in rb_erase()
  [RBTREE] Update JFFS2 to use rb_parent() accessor macro.
  [RBTREE] Update eventpoll.c to use rb_parent() accessor macro.
  [RBTREE] Update key.c to use rb_parent() accessor macro.
  [RBTREE] Update ext3 to use rb_parent() accessor macro.
  [RBTREE] Change rbtree off-tree marking in I/O schedulers.
  [RBTREE] Add accessor macros for colour and parent fields of rb_node

arch/um/kernel/physmem.c

@@ -69,7 +69,7 @@ static void insert_phys_mapping(struct phys_desc *desc)
 		panic("Physical remapping for %p already present",
 		      desc->virt);
 
-	rb_link_node(&desc->rb, (*n)->rb_parent, n);
+	rb_link_node(&desc->rb, rb_parent(*n), n);
 	rb_insert_color(&desc->rb, &phys_mappings);
 }
 

block/as-iosched.c

@@ -353,10 +353,9 @@ static struct request *as_find_arq_hash(struct as_data *ad, sector_t offset)
 /*
  * rb tree support functions
  */
-#define RB_NONE		(2)
 #define RB_EMPTY(root)	((root)->rb_node == NULL)
-#define ON_RB(node)	((node)->rb_color != RB_NONE)
-#define RB_CLEAR(node)	((node)->rb_color = RB_NONE)
+#define ON_RB(node)	(rb_parent(node) != node)
+#define RB_CLEAR(node)	(rb_set_parent(node, node))
 #define rb_entry_arq(node)	rb_entry((node), struct as_rq, rb_node)
 #define ARQ_RB_ROOT(ad, arq)	(&(ad)->sort_list[(arq)->is_sync])
 #define rq_rb_key(rq)		(rq)->sector

block/cfq-iosched.c

@@ -60,14 +60,9 @@ static DEFINE_SPINLOCK(cfq_exit_lock);
 /*
  * rb-tree defines
  */
-#define RB_NONE			(2)
 #define RB_EMPTY(node)		((node)->rb_node == NULL)
-#define RB_CLEAR_COLOR(node)	(node)->rb_color = RB_NONE
 #define RB_CLEAR(node)		do {	\
-	(node)->rb_parent = NULL;	\
-	RB_CLEAR_COLOR((node));		\
-	(node)->rb_right = NULL;	\
-	(node)->rb_left = NULL;		\
+		memset(node, 0, sizeof(*node)); \
 } while (0)
 #define RB_CLEAR_ROOT(root)	((root)->rb_node = NULL)
 #define rb_entry_crq(node)	rb_entry((node), struct cfq_rq, rb_node)
@@ -567,7 +562,6 @@ static inline void cfq_del_crq_rb(struct cfq_rq *crq)
 	cfq_update_next_crq(crq);
 
 	rb_erase(&crq->rb_node, &cfqq->sort_list);
-	RB_CLEAR_COLOR(&crq->rb_node);
 
 	if (cfq_cfqq_on_rr(cfqq) && RB_EMPTY(&cfqq->sort_list))
 		cfq_del_cfqq_rr(cfqd, cfqq);

block/deadline-iosched.c

@@ -165,10 +165,9 @@ deadline_find_drq_hash(struct deadline_data *dd, sector_t offset)
 /*
  * rb tree support functions
  */
-#define RB_NONE		(2)
 #define RB_EMPTY(root)	((root)->rb_node == NULL)
-#define ON_RB(node)	((node)->rb_color != RB_NONE)
-#define RB_CLEAR(node)	((node)->rb_color = RB_NONE)
+#define ON_RB(node)	(rb_parent(node) != node)
+#define RB_CLEAR(node)	(rb_set_parent(node, node))
 #define rb_entry_drq(node)	rb_entry((node), struct deadline_rq, rb_node)
 #define DRQ_RB_ROOT(dd, drq)	(&(dd)->sort_list[rq_data_dir((drq)->request)])
 #define rq_rb_key(rq)		(rq)->sector

fs/eventpoll.c

@@ -337,20 +337,20 @@ static inline int ep_cmp_ffd(struct epoll_filefd *p1,
 /* Special initialization for the rb-tree node to detect linkage */
 static inline void ep_rb_initnode(struct rb_node *n)
 {
-	n->rb_parent = n;
+	rb_set_parent(n, n);
 }
 
 /* Removes a node from the rb-tree and marks it for a fast is-linked check */
 static inline void ep_rb_erase(struct rb_node *n, struct rb_root *r)
 {
 	rb_erase(n, r);
-	n->rb_parent = n;
+	rb_set_parent(n, n);
 }
 
 /* Fast check to verify that the item is linked to the main rb-tree */
 static inline int ep_rb_linked(struct rb_node *n)
 {
-	return n->rb_parent != n;
+	return rb_parent(n) != n;
 }
 
 /*

fs/ext3/dir.c

@@ -284,7 +284,7 @@ static void free_rb_tree_fname(struct rb_root *root)
 		 * beginning of the loop and try to free the parent
 		 * node.
 		 */
-		parent = n->rb_parent;
+		parent = rb_parent(n);
 		fname = rb_entry(n, struct fname, rb_hash);
 		while (fname) {
 			struct fname * old = fname;

fs/jffs2/nodelist.h

@@ -315,7 +315,6 @@ static inline struct jffs2_node_frag *frag_last(struct rb_root *root)
 	return rb_entry(node, struct jffs2_node_frag, rb);
 }
 
-#define rb_parent(rb) ((rb)->rb_parent)
 #define frag_next(frag) rb_entry(rb_next(&(frag)->rb), struct jffs2_node_frag, rb)
 #define frag_prev(frag) rb_entry(rb_prev(&(frag)->rb), struct jffs2_node_frag, rb)
 #define frag_parent(frag) rb_entry(rb_parent(&(frag)->rb), struct jffs2_node_frag, rb)

fs/jffs2/readinode.c

@@ -66,7 +66,7 @@ static void jffs2_free_tmp_dnode_info_list(struct rb_root *list)
 			jffs2_free_full_dnode(tn->fn);
 			jffs2_free_tmp_dnode_info(tn);
 
-			this = this->rb_parent;
+			this = rb_parent(this);
 			if (!this)
 				break;
 
@@ -708,27 +708,27 @@ static int jffs2_do_read_inode_internal(struct jffs2_sb_info *c,
 			jffs2_mark_node_obsolete(c, fn->raw);
 
 		BUG_ON(rb->rb_left);
-		if (rb->rb_parent && rb->rb_parent->rb_left == rb) {
+		if (rb_parent(rb) && rb_parent(rb)->rb_left == rb) {
 			/* We were then left-hand child of our parent. We need
 			 * to move our own right-hand child into our place. */
 			repl_rb = rb->rb_right;
 			if (repl_rb)
-				repl_rb->rb_parent = rb->rb_parent;
+				rb_set_parent(repl_rb, rb_parent(rb));
 		} else
 			repl_rb = NULL;
 
 		rb = rb_next(rb);
 
 		/* Remove the spent tn from the tree; don't bother rebalancing
 		 * but put our right-hand child in our own place. */
-		if (tn->rb.rb_parent) {
-			if (tn->rb.rb_parent->rb_left == &tn->rb)
-				tn->rb.rb_parent->rb_left = repl_rb;
-			else if (tn->rb.rb_parent->rb_right == &tn->rb)
-				tn->rb.rb_parent->rb_right = repl_rb;
+		if (rb_parent(&tn->rb)) {
+			if (rb_parent(&tn->rb)->rb_left == &tn->rb)
+				rb_parent(&tn->rb)->rb_left = repl_rb;
+			else if (rb_parent(&tn->rb)->rb_right == &tn->rb)
+				rb_parent(&tn->rb)->rb_right = repl_rb;
 			else BUG();
 		} else if (tn->rb.rb_right)
-			tn->rb.rb_right->rb_parent = NULL;
+			rb_set_parent(tn->rb.rb_right, NULL);
 
 		jffs2_free_tmp_dnode_info(tn);
 		if (ret) {

include/linux/hrtimer.h

@@ -127,7 +127,7 @@ extern ktime_t hrtimer_get_next_event(void);
 
 static inline int hrtimer_active(const struct hrtimer *timer)
 {
-	return timer->node.rb_parent != HRTIMER_INACTIVE;
+	return rb_parent(&timer->node) != &timer->node;
 }
 
 /* Forward a hrtimer so it expires after now: */

include/linux/rbtree.h

@@ -99,19 +99,36 @@ static inline struct page * rb_insert_page_cache(struct inode * inode,
 
 struct rb_node
 {
-	struct rb_node *rb_parent;
-	int rb_color;
+	unsigned long  rb_parent_color;
 #define	RB_RED		0
 #define	RB_BLACK	1
 	struct rb_node *rb_right;
 	struct rb_node *rb_left;
-};
+} __attribute__((aligned(sizeof(long))));
+    /* The alignment might seem pointless, but allegedly CRIS needs it */
 
 struct rb_root
 {
 	struct rb_node *rb_node;
 };
 
+
+#define rb_parent(r)   ((struct rb_node *)((r)->rb_parent_color & ~3))
+#define rb_color(r)   ((r)->rb_parent_color & 1)
+#define rb_is_red(r)   (!rb_color(r))
+#define rb_is_black(r) rb_color(r)
+#define rb_set_red(r)  do { (r)->rb_parent_color &= ~1; } while (0)
+#define rb_set_black(r)  do { (r)->rb_parent_color |= 1; } while (0)
+
+static inline void rb_set_parent(struct rb_node *rb, struct rb_node *p)
+{
+	rb->rb_parent_color = (rb->rb_parent_color & 3) | (unsigned long)p;
+}
+static inline void rb_set_color(struct rb_node *rb, int color)
+{
+	rb->rb_parent_color = (rb->rb_parent_color & ~1) | color;
+}
+
 #define RB_ROOT	(struct rb_root) { NULL, }
 #define	rb_entry(ptr, type, member) container_of(ptr, type, member)
 
@@ -131,8 +148,7 @@ extern void rb_replace_node(struct rb_node *victim, struct rb_node *new,
 static inline void rb_link_node(struct rb_node * node, struct rb_node * parent,
 				struct rb_node ** rb_link)
 {
-	node->rb_parent = parent;
-	node->rb_color = RB_RED;
+	node->rb_parent_color = (unsigned long )parent;
 	node->rb_left = node->rb_right = NULL;
 
 	*rb_link = node;

kernel/hrtimer.c

@@ -393,7 +393,7 @@ static void __remove_hrtimer(struct hrtimer *timer, struct hrtimer_base *base)
 	if (base->first == &timer->node)
 		base->first = rb_next(&timer->node);
 	rb_erase(&timer->node, &base->active);
-	timer->node.rb_parent = HRTIMER_INACTIVE;
+	rb_set_parent(&timer->node, &timer->node);
 }
 
 /*
@@ -582,7 +582,7 @@ void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 		clock_id = CLOCK_MONOTONIC;
 
 	timer->base = &bases[clock_id];
-	timer->node.rb_parent = HRTIMER_INACTIVE;
+	rb_set_parent(&timer->node, &timer->node);
 }
 EXPORT_SYMBOL_GPL(hrtimer_init);