lib, rbtree: resync with Linux-3.14
resync with linux: commit 455c6fdbd219161bd09b1165f11699d6d73de11c Author: Linus Torvalds <torvalds@linux-foundation.org> Date: Sun Mar 30 20:40:15 2014 -0700 Linux 3.14 Needed for the MTD/UBI/UBIFS resync Just copied the files from Linux, changed the license file header, and add in the c-file: +#define __UBOOT__ #include <linux/rbtree_augmented.h> +#ifndef __UBOOT__ #include <linux/export.h> +#else +#include <ubi_uboot.h> +#endif so, it compiles for U-Boot. Signed-off-by: Heiko Schocher <hs@denx.de> Cc: Marek Vasut <marex@denx.de> Cc: Sergey Lapin <slapin@ossfans.org> Cc: Scott Wood <scottwood@freescale.com> Cc: Tom Rini <trini@ti.com>
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parent
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commit
9dd228b5e7
@ -1,7 +1,7 @@
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/*
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Red Black Trees
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(C) 1999 Andrea Arcangeli <andrea@suse.de>
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* SPDX-License-Identifier: GPL-2.0+
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linux/include/linux/rbtree.h
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@ -11,138 +11,89 @@
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I know it's not the cleaner way, but in C (not in C++) to get
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performances and genericity...
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Some example of insert and search follows here. The search is a plain
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normal search over an ordered tree. The insert instead must be implemented
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int two steps: as first thing the code must insert the element in
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order as a red leaf in the tree, then the support library function
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rb_insert_color() must be called. Such function will do the
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not trivial work to rebalance the rbtree if necessary.
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-----------------------------------------------------------------------
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static inline struct page * rb_search_page_cache(struct inode * inode,
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unsigned long offset)
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{
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struct rb_node * n = inode->i_rb_page_cache.rb_node;
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struct page * page;
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while (n)
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{
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page = rb_entry(n, struct page, rb_page_cache);
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if (offset < page->offset)
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n = n->rb_left;
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else if (offset > page->offset)
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n = n->rb_right;
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else
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return page;
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}
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return NULL;
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}
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static inline struct page * __rb_insert_page_cache(struct inode * inode,
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unsigned long offset,
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struct rb_node * node)
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{
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struct rb_node ** p = &inode->i_rb_page_cache.rb_node;
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struct rb_node * parent = NULL;
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struct page * page;
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while (*p)
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{
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parent = *p;
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page = rb_entry(parent, struct page, rb_page_cache);
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if (offset < page->offset)
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p = &(*p)->rb_left;
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else if (offset > page->offset)
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p = &(*p)->rb_right;
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else
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return page;
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}
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rb_link_node(node, parent, p);
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return NULL;
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}
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static inline struct page * rb_insert_page_cache(struct inode * inode,
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unsigned long offset,
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struct rb_node * node)
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{
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struct page * ret;
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if ((ret = __rb_insert_page_cache(inode, offset, node)))
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goto out;
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rb_insert_color(node, &inode->i_rb_page_cache);
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out:
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return ret;
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}
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-----------------------------------------------------------------------
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See Documentation/rbtree.txt for documentation and samples.
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*/
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#ifndef _LINUX_RBTREE_H
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#define _LINUX_RBTREE_H
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#define __UBOOT__
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#ifndef __UBOOT__
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#include <linux/kernel.h>
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#endif
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#include <linux/stddef.h>
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struct rb_node
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{
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unsigned long rb_parent_color;
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#define RB_RED 0
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#define RB_BLACK 1
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struct rb_node {
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unsigned long __rb_parent_color;
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struct rb_node *rb_right;
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struct rb_node *rb_left;
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} __attribute__((aligned(sizeof(long))));
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/* The alignment might seem pointless, but allegedly CRIS needs it */
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struct rb_root
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{
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struct rb_root {
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struct rb_node *rb_node;
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};
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#define rb_parent(r) ((struct rb_node *)((r)->rb_parent_color & ~3))
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#define rb_color(r) ((r)->rb_parent_color & 1)
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#define rb_is_red(r) (!rb_color(r))
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#define rb_is_black(r) rb_color(r)
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#define rb_set_red(r) do { (r)->rb_parent_color &= ~1; } while (0)
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#define rb_set_black(r) do { (r)->rb_parent_color |= 1; } while (0)
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static inline void rb_set_parent(struct rb_node *rb, struct rb_node *p)
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{
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rb->rb_parent_color = (rb->rb_parent_color & 3) | (unsigned long)p;
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}
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static inline void rb_set_color(struct rb_node *rb, int color)
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{
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rb->rb_parent_color = (rb->rb_parent_color & ~1) | color;
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}
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#define rb_parent(r) ((struct rb_node *)((r)->__rb_parent_color & ~3))
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#define RB_ROOT (struct rb_root) { NULL, }
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#define rb_entry(ptr, type, member) container_of(ptr, type, member)
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#define RB_EMPTY_ROOT(root) ((root)->rb_node == NULL)
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#define RB_EMPTY_NODE(node) (rb_parent(node) == node)
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#define RB_CLEAR_NODE(node) (rb_set_parent(node, node))
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#define RB_EMPTY_ROOT(root) ((root)->rb_node == NULL)
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/* 'empty' nodes are nodes that are known not to be inserted in an rbree */
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#define RB_EMPTY_NODE(node) \
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((node)->__rb_parent_color == (unsigned long)(node))
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#define RB_CLEAR_NODE(node) \
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((node)->__rb_parent_color = (unsigned long)(node))
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extern void rb_insert_color(struct rb_node *, struct rb_root *);
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extern void rb_erase(struct rb_node *, struct rb_root *);
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/* Find logical next and previous nodes in a tree */
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extern struct rb_node *rb_next(struct rb_node *);
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extern struct rb_node *rb_prev(struct rb_node *);
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extern struct rb_node *rb_first(struct rb_root *);
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extern struct rb_node *rb_last(struct rb_root *);
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extern struct rb_node *rb_next(const struct rb_node *);
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extern struct rb_node *rb_prev(const struct rb_node *);
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extern struct rb_node *rb_first(const struct rb_root *);
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extern struct rb_node *rb_last(const struct rb_root *);
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/* Postorder iteration - always visit the parent after its children */
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extern struct rb_node *rb_first_postorder(const struct rb_root *);
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extern struct rb_node *rb_next_postorder(const struct rb_node *);
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/* Fast replacement of a single node without remove/rebalance/add/rebalance */
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extern void rb_replace_node(struct rb_node *victim, struct rb_node *new,
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extern void rb_replace_node(struct rb_node *victim, struct rb_node *new,
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struct rb_root *root);
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static inline void rb_link_node(struct rb_node * node, struct rb_node * parent,
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struct rb_node ** rb_link)
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{
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node->rb_parent_color = (unsigned long )parent;
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node->__rb_parent_color = (unsigned long)parent;
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node->rb_left = node->rb_right = NULL;
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*rb_link = node;
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}
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#define rb_entry_safe(ptr, type, member) \
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({ typeof(ptr) ____ptr = (ptr); \
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____ptr ? rb_entry(____ptr, type, member) : NULL; \
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})
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/**
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* rbtree_postorder_for_each_entry_safe - iterate over rb_root in post order of
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* given type safe against removal of rb_node entry
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*
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* @pos: the 'type *' to use as a loop cursor.
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* @n: another 'type *' to use as temporary storage
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* @root: 'rb_root *' of the rbtree.
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* @field: the name of the rb_node field within 'type'.
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*/
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#define rbtree_postorder_for_each_entry_safe(pos, n, root, field) \
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for (pos = rb_entry_safe(rb_first_postorder(root), typeof(*pos), field); \
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pos && ({ n = rb_entry_safe(rb_next_postorder(&pos->field), \
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typeof(*pos), field); 1; }); \
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pos = n)
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#endif /* _LINUX_RBTREE_H */
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include/linux/rbtree_augmented.h
Normal file
220
include/linux/rbtree_augmented.h
Normal file
@ -0,0 +1,220 @@
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/*
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Red Black Trees
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(C) 1999 Andrea Arcangeli <andrea@suse.de>
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(C) 2002 David Woodhouse <dwmw2@infradead.org>
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(C) 2012 Michel Lespinasse <walken@google.com>
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* SPDX-License-Identifier: GPL-2.0+
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linux/include/linux/rbtree_augmented.h
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*/
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#ifndef _LINUX_RBTREE_AUGMENTED_H
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#define _LINUX_RBTREE_AUGMENTED_H
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#include <linux/compiler.h>
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#include <linux/rbtree.h>
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/*
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* Please note - only struct rb_augment_callbacks and the prototypes for
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* rb_insert_augmented() and rb_erase_augmented() are intended to be public.
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* The rest are implementation details you are not expected to depend on.
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*
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* See Documentation/rbtree.txt for documentation and samples.
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*/
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struct rb_augment_callbacks {
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void (*propagate)(struct rb_node *node, struct rb_node *stop);
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void (*copy)(struct rb_node *old, struct rb_node *new);
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void (*rotate)(struct rb_node *old, struct rb_node *new);
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};
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extern void __rb_insert_augmented(struct rb_node *node, struct rb_root *root,
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void (*augment_rotate)(struct rb_node *old, struct rb_node *new));
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static inline void
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rb_insert_augmented(struct rb_node *node, struct rb_root *root,
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const struct rb_augment_callbacks *augment)
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{
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__rb_insert_augmented(node, root, augment->rotate);
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}
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#define RB_DECLARE_CALLBACKS(rbstatic, rbname, rbstruct, rbfield, \
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rbtype, rbaugmented, rbcompute) \
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static inline void \
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rbname ## _propagate(struct rb_node *rb, struct rb_node *stop) \
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{ \
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while (rb != stop) { \
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rbstruct *node = rb_entry(rb, rbstruct, rbfield); \
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rbtype augmented = rbcompute(node); \
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if (node->rbaugmented == augmented) \
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break; \
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node->rbaugmented = augmented; \
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rb = rb_parent(&node->rbfield); \
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} \
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} \
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static inline void \
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rbname ## _copy(struct rb_node *rb_old, struct rb_node *rb_new) \
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{ \
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rbstruct *old = rb_entry(rb_old, rbstruct, rbfield); \
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rbstruct *new = rb_entry(rb_new, rbstruct, rbfield); \
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new->rbaugmented = old->rbaugmented; \
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} \
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static void \
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rbname ## _rotate(struct rb_node *rb_old, struct rb_node *rb_new) \
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{ \
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rbstruct *old = rb_entry(rb_old, rbstruct, rbfield); \
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rbstruct *new = rb_entry(rb_new, rbstruct, rbfield); \
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new->rbaugmented = old->rbaugmented; \
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old->rbaugmented = rbcompute(old); \
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} \
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rbstatic const struct rb_augment_callbacks rbname = { \
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rbname ## _propagate, rbname ## _copy, rbname ## _rotate \
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};
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#define RB_RED 0
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#define RB_BLACK 1
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#define __rb_parent(pc) ((struct rb_node *)(pc & ~3))
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#define __rb_color(pc) ((pc) & 1)
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#define __rb_is_black(pc) __rb_color(pc)
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#define __rb_is_red(pc) (!__rb_color(pc))
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#define rb_color(rb) __rb_color((rb)->__rb_parent_color)
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#define rb_is_red(rb) __rb_is_red((rb)->__rb_parent_color)
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#define rb_is_black(rb) __rb_is_black((rb)->__rb_parent_color)
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static inline void rb_set_parent(struct rb_node *rb, struct rb_node *p)
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{
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rb->__rb_parent_color = rb_color(rb) | (unsigned long)p;
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}
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static inline void rb_set_parent_color(struct rb_node *rb,
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struct rb_node *p, int color)
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{
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rb->__rb_parent_color = (unsigned long)p | color;
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}
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static inline void
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__rb_change_child(struct rb_node *old, struct rb_node *new,
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struct rb_node *parent, struct rb_root *root)
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{
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if (parent) {
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if (parent->rb_left == old)
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parent->rb_left = new;
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else
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parent->rb_right = new;
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} else
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root->rb_node = new;
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}
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extern void __rb_erase_color(struct rb_node *parent, struct rb_root *root,
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void (*augment_rotate)(struct rb_node *old, struct rb_node *new));
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static __always_inline struct rb_node *
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__rb_erase_augmented(struct rb_node *node, struct rb_root *root,
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const struct rb_augment_callbacks *augment)
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{
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struct rb_node *child = node->rb_right, *tmp = node->rb_left;
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struct rb_node *parent, *rebalance;
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unsigned long pc;
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if (!tmp) {
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/*
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* Case 1: node to erase has no more than 1 child (easy!)
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*
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* Note that if there is one child it must be red due to 5)
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* and node must be black due to 4). We adjust colors locally
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* so as to bypass __rb_erase_color() later on.
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*/
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pc = node->__rb_parent_color;
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parent = __rb_parent(pc);
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__rb_change_child(node, child, parent, root);
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if (child) {
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child->__rb_parent_color = pc;
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rebalance = NULL;
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} else
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rebalance = __rb_is_black(pc) ? parent : NULL;
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tmp = parent;
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} else if (!child) {
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/* Still case 1, but this time the child is node->rb_left */
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tmp->__rb_parent_color = pc = node->__rb_parent_color;
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parent = __rb_parent(pc);
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__rb_change_child(node, tmp, parent, root);
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rebalance = NULL;
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tmp = parent;
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} else {
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struct rb_node *successor = child, *child2;
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tmp = child->rb_left;
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if (!tmp) {
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/*
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* Case 2: node's successor is its right child
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*
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* (n) (s)
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* / \ / \
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* (x) (s) -> (x) (c)
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* \
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* (c)
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*/
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parent = successor;
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child2 = successor->rb_right;
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augment->copy(node, successor);
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} else {
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/*
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* Case 3: node's successor is leftmost under
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* node's right child subtree
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*
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* (n) (s)
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* / \ / \
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* (x) (y) -> (x) (y)
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* / /
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* (p) (p)
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* / /
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* (s) (c)
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* \
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* (c)
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*/
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do {
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parent = successor;
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successor = tmp;
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tmp = tmp->rb_left;
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} while (tmp);
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parent->rb_left = child2 = successor->rb_right;
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successor->rb_right = child;
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rb_set_parent(child, successor);
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augment->copy(node, successor);
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augment->propagate(parent, successor);
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}
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successor->rb_left = tmp = node->rb_left;
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rb_set_parent(tmp, successor);
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pc = node->__rb_parent_color;
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tmp = __rb_parent(pc);
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__rb_change_child(node, successor, tmp, root);
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if (child2) {
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successor->__rb_parent_color = pc;
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rb_set_parent_color(child2, parent, RB_BLACK);
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rebalance = NULL;
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} else {
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unsigned long pc2 = successor->__rb_parent_color;
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successor->__rb_parent_color = pc;
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rebalance = __rb_is_black(pc2) ? parent : NULL;
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}
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tmp = successor;
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}
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augment->propagate(tmp, NULL);
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return rebalance;
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}
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static __always_inline void
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rb_erase_augmented(struct rb_node *node, struct rb_root *root,
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const struct rb_augment_callbacks *augment)
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{
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struct rb_node *rebalance = __rb_erase_augmented(node, root, augment);
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if (rebalance)
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__rb_erase_color(rebalance, root, augment->rotate);
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}
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#endif /* _LINUX_RBTREE_AUGMENTED_H */
|
736
lib/rbtree.c
736
lib/rbtree.c
@ -2,283 +2,412 @@
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Red Black Trees
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(C) 1999 Andrea Arcangeli <andrea@suse.de>
|
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(C) 2002 David Woodhouse <dwmw2@infradead.org>
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(C) 2012 Michel Lespinasse <walken@google.com>
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* SPDX-License-Identifier: GPL-2.0+
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linux/lib/rbtree.c
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*/
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#define __UBOOT__
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#include <linux/rbtree_augmented.h>
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#ifndef __UBOOT__
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#include <linux/export.h>
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#else
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#include <ubi_uboot.h>
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#include <linux/rbtree.h>
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#endif
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/*
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* red-black trees properties: http://en.wikipedia.org/wiki/Rbtree
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*
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* 1) A node is either red or black
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* 2) The root is black
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* 3) All leaves (NULL) are black
|
||||
* 4) Both children of every red node are black
|
||||
* 5) Every simple path from root to leaves contains the same number
|
||||
* of black nodes.
|
||||
*
|
||||
* 4 and 5 give the O(log n) guarantee, since 4 implies you cannot have two
|
||||
* consecutive red nodes in a path and every red node is therefore followed by
|
||||
* a black. So if B is the number of black nodes on every simple path (as per
|
||||
* 5), then the longest possible path due to 4 is 2B.
|
||||
*
|
||||
* We shall indicate color with case, where black nodes are uppercase and red
|
||||
* nodes will be lowercase. Unknown color nodes shall be drawn as red within
|
||||
* parentheses and have some accompanying text comment.
|
||||
*/
|
||||
|
||||
static void __rb_rotate_left(struct rb_node *node, struct rb_root *root)
|
||||
static inline void rb_set_black(struct rb_node *rb)
|
||||
{
|
||||
struct rb_node *right = node->rb_right;
|
||||
struct rb_node *parent = rb_parent(node);
|
||||
|
||||
if ((node->rb_right = right->rb_left))
|
||||
rb_set_parent(right->rb_left, node);
|
||||
right->rb_left = node;
|
||||
|
||||
rb_set_parent(right, parent);
|
||||
|
||||
if (parent)
|
||||
{
|
||||
if (node == parent->rb_left)
|
||||
parent->rb_left = right;
|
||||
else
|
||||
parent->rb_right = right;
|
||||
}
|
||||
else
|
||||
root->rb_node = right;
|
||||
rb_set_parent(node, right);
|
||||
rb->__rb_parent_color |= RB_BLACK;
|
||||
}
|
||||
|
||||
static void __rb_rotate_right(struct rb_node *node, struct rb_root *root)
|
||||
static inline struct rb_node *rb_red_parent(struct rb_node *red)
|
||||
{
|
||||
struct rb_node *left = node->rb_left;
|
||||
struct rb_node *parent = rb_parent(node);
|
||||
|
||||
if ((node->rb_left = left->rb_right))
|
||||
rb_set_parent(left->rb_right, node);
|
||||
left->rb_right = node;
|
||||
|
||||
rb_set_parent(left, parent);
|
||||
|
||||
if (parent)
|
||||
{
|
||||
if (node == parent->rb_right)
|
||||
parent->rb_right = left;
|
||||
else
|
||||
parent->rb_left = left;
|
||||
}
|
||||
else
|
||||
root->rb_node = left;
|
||||
rb_set_parent(node, left);
|
||||
return (struct rb_node *)red->__rb_parent_color;
|
||||
}
|
||||
|
||||
/*
|
||||
* Helper function for rotations:
|
||||
* - old's parent and color get assigned to new
|
||||
* - old gets assigned new as a parent and 'color' as a color.
|
||||
*/
|
||||
static inline void
|
||||
__rb_rotate_set_parents(struct rb_node *old, struct rb_node *new,
|
||||
struct rb_root *root, int color)
|
||||
{
|
||||
struct rb_node *parent = rb_parent(old);
|
||||
new->__rb_parent_color = old->__rb_parent_color;
|
||||
rb_set_parent_color(old, new, color);
|
||||
__rb_change_child(old, new, parent, root);
|
||||
}
|
||||
|
||||
static __always_inline void
|
||||
__rb_insert(struct rb_node *node, struct rb_root *root,
|
||||
void (*augment_rotate)(struct rb_node *old, struct rb_node *new))
|
||||
{
|
||||
struct rb_node *parent = rb_red_parent(node), *gparent, *tmp;
|
||||
|
||||
while (true) {
|
||||
/*
|
||||
* Loop invariant: node is red
|
||||
*
|
||||
* If there is a black parent, we are done.
|
||||
* Otherwise, take some corrective action as we don't
|
||||
* want a red root or two consecutive red nodes.
|
||||
*/
|
||||
if (!parent) {
|
||||
rb_set_parent_color(node, NULL, RB_BLACK);
|
||||
break;
|
||||
} else if (rb_is_black(parent))
|
||||
break;
|
||||
|
||||
gparent = rb_red_parent(parent);
|
||||
|
||||
tmp = gparent->rb_right;
|
||||
if (parent != tmp) { /* parent == gparent->rb_left */
|
||||
if (tmp && rb_is_red(tmp)) {
|
||||
/*
|
||||
* Case 1 - color flips
|
||||
*
|
||||
* G g
|
||||
* / \ / \
|
||||
* p u --> P U
|
||||
* / /
|
||||
* n N
|
||||
*
|
||||
* However, since g's parent might be red, and
|
||||
* 4) does not allow this, we need to recurse
|
||||
* at g.
|
||||
*/
|
||||
rb_set_parent_color(tmp, gparent, RB_BLACK);
|
||||
rb_set_parent_color(parent, gparent, RB_BLACK);
|
||||
node = gparent;
|
||||
parent = rb_parent(node);
|
||||
rb_set_parent_color(node, parent, RB_RED);
|
||||
continue;
|
||||
}
|
||||
|
||||
tmp = parent->rb_right;
|
||||
if (node == tmp) {
|
||||
/*
|
||||
* Case 2 - left rotate at parent
|
||||
*
|
||||
* G G
|
||||
* / \ / \
|
||||
* p U --> n U
|
||||
* \ /
|
||||
* n p
|
||||
*
|
||||
* This still leaves us in violation of 4), the
|
||||
* continuation into Case 3 will fix that.
|
||||
*/
|
||||
parent->rb_right = tmp = node->rb_left;
|
||||
node->rb_left = parent;
|
||||
if (tmp)
|
||||
rb_set_parent_color(tmp, parent,
|
||||
RB_BLACK);
|
||||
rb_set_parent_color(parent, node, RB_RED);
|
||||
augment_rotate(parent, node);
|
||||
parent = node;
|
||||
tmp = node->rb_right;
|
||||
}
|
||||
|
||||
/*
|
||||
* Case 3 - right rotate at gparent
|
||||
*
|
||||
* G P
|
||||
* / \ / \
|
||||
* p U --> n g
|
||||
* / \
|
||||
* n U
|
||||
*/
|
||||
gparent->rb_left = tmp; /* == parent->rb_right */
|
||||
parent->rb_right = gparent;
|
||||
if (tmp)
|
||||
rb_set_parent_color(tmp, gparent, RB_BLACK);
|
||||
__rb_rotate_set_parents(gparent, parent, root, RB_RED);
|
||||
augment_rotate(gparent, parent);
|
||||
break;
|
||||
} else {
|
||||
tmp = gparent->rb_left;
|
||||
if (tmp && rb_is_red(tmp)) {
|
||||
/* Case 1 - color flips */
|
||||
rb_set_parent_color(tmp, gparent, RB_BLACK);
|
||||
rb_set_parent_color(parent, gparent, RB_BLACK);
|
||||
node = gparent;
|
||||
parent = rb_parent(node);
|
||||
rb_set_parent_color(node, parent, RB_RED);
|
||||
continue;
|
||||
}
|
||||
|
||||
tmp = parent->rb_left;
|
||||
if (node == tmp) {
|
||||
/* Case 2 - right rotate at parent */
|
||||
parent->rb_left = tmp = node->rb_right;
|
||||
node->rb_right = parent;
|
||||
if (tmp)
|
||||
rb_set_parent_color(tmp, parent,
|
||||
RB_BLACK);
|
||||
rb_set_parent_color(parent, node, RB_RED);
|
||||
augment_rotate(parent, node);
|
||||
parent = node;
|
||||
tmp = node->rb_left;
|
||||
}
|
||||
|
||||
/* Case 3 - left rotate at gparent */
|
||||
gparent->rb_right = tmp; /* == parent->rb_left */
|
||||
parent->rb_left = gparent;
|
||||
if (tmp)
|
||||
rb_set_parent_color(tmp, gparent, RB_BLACK);
|
||||
__rb_rotate_set_parents(gparent, parent, root, RB_RED);
|
||||
augment_rotate(gparent, parent);
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* Inline version for rb_erase() use - we want to be able to inline
|
||||
* and eliminate the dummy_rotate callback there
|
||||
*/
|
||||
static __always_inline void
|
||||
____rb_erase_color(struct rb_node *parent, struct rb_root *root,
|
||||
void (*augment_rotate)(struct rb_node *old, struct rb_node *new))
|
||||
{
|
||||
struct rb_node *node = NULL, *sibling, *tmp1, *tmp2;
|
||||
|
||||
while (true) {
|
||||
/*
|
||||
* Loop invariants:
|
||||
* - node is black (or NULL on first iteration)
|
||||
* - node is not the root (parent is not NULL)
|
||||
* - All leaf paths going through parent and node have a
|
||||
* black node count that is 1 lower than other leaf paths.
|
||||
*/
|
||||
sibling = parent->rb_right;
|
||||
if (node != sibling) { /* node == parent->rb_left */
|
||||
if (rb_is_red(sibling)) {
|
||||
/*
|
||||
* Case 1 - left rotate at parent
|
||||
*
|
||||
* P S
|
||||
* / \ / \
|
||||
* N s --> p Sr
|
||||
* / \ / \
|
||||
* Sl Sr N Sl
|
||||
*/
|
||||
parent->rb_right = tmp1 = sibling->rb_left;
|
||||
sibling->rb_left = parent;
|
||||
rb_set_parent_color(tmp1, parent, RB_BLACK);
|
||||
__rb_rotate_set_parents(parent, sibling, root,
|
||||
RB_RED);
|
||||
augment_rotate(parent, sibling);
|
||||
sibling = tmp1;
|
||||
}
|
||||
tmp1 = sibling->rb_right;
|
||||
if (!tmp1 || rb_is_black(tmp1)) {
|
||||
tmp2 = sibling->rb_left;
|
||||
if (!tmp2 || rb_is_black(tmp2)) {
|
||||
/*
|
||||
* Case 2 - sibling color flip
|
||||
* (p could be either color here)
|
||||
*
|
||||
* (p) (p)
|
||||
* / \ / \
|
||||
* N S --> N s
|
||||
* / \ / \
|
||||
* Sl Sr Sl Sr
|
||||
*
|
||||
* This leaves us violating 5) which
|
||||
* can be fixed by flipping p to black
|
||||
* if it was red, or by recursing at p.
|
||||
* p is red when coming from Case 1.
|
||||
*/
|
||||
rb_set_parent_color(sibling, parent,
|
||||
RB_RED);
|
||||
if (rb_is_red(parent))
|
||||
rb_set_black(parent);
|
||||
else {
|
||||
node = parent;
|
||||
parent = rb_parent(node);
|
||||
if (parent)
|
||||
continue;
|
||||
}
|
||||
break;
|
||||
}
|
||||
/*
|
||||
* Case 3 - right rotate at sibling
|
||||
* (p could be either color here)
|
||||
*
|
||||
* (p) (p)
|
||||
* / \ / \
|
||||
* N S --> N Sl
|
||||
* / \ \
|
||||
* sl Sr s
|
||||
* \
|
||||
* Sr
|
||||
*/
|
||||
sibling->rb_left = tmp1 = tmp2->rb_right;
|
||||
tmp2->rb_right = sibling;
|
||||
parent->rb_right = tmp2;
|
||||
if (tmp1)
|
||||
rb_set_parent_color(tmp1, sibling,
|
||||
RB_BLACK);
|
||||
augment_rotate(sibling, tmp2);
|
||||
tmp1 = sibling;
|
||||
sibling = tmp2;
|
||||
}
|
||||
/*
|
||||
* Case 4 - left rotate at parent + color flips
|
||||
* (p and sl could be either color here.
|
||||
* After rotation, p becomes black, s acquires
|
||||
* p's color, and sl keeps its color)
|
||||
*
|
||||
* (p) (s)
|
||||
* / \ / \
|
||||
* N S --> P Sr
|
||||
* / \ / \
|
||||
* (sl) sr N (sl)
|
||||
*/
|
||||
parent->rb_right = tmp2 = sibling->rb_left;
|
||||
sibling->rb_left = parent;
|
||||
rb_set_parent_color(tmp1, sibling, RB_BLACK);
|
||||
if (tmp2)
|
||||
rb_set_parent(tmp2, parent);
|
||||
__rb_rotate_set_parents(parent, sibling, root,
|
||||
RB_BLACK);
|
||||
augment_rotate(parent, sibling);
|
||||
break;
|
||||
} else {
|
||||
sibling = parent->rb_left;
|
||||
if (rb_is_red(sibling)) {
|
||||
/* Case 1 - right rotate at parent */
|
||||
parent->rb_left = tmp1 = sibling->rb_right;
|
||||
sibling->rb_right = parent;
|
||||
rb_set_parent_color(tmp1, parent, RB_BLACK);
|
||||
__rb_rotate_set_parents(parent, sibling, root,
|
||||
RB_RED);
|
||||
augment_rotate(parent, sibling);
|
||||
sibling = tmp1;
|
||||
}
|
||||
tmp1 = sibling->rb_left;
|
||||
if (!tmp1 || rb_is_black(tmp1)) {
|
||||
tmp2 = sibling->rb_right;
|
||||
if (!tmp2 || rb_is_black(tmp2)) {
|
||||
/* Case 2 - sibling color flip */
|
||||
rb_set_parent_color(sibling, parent,
|
||||
RB_RED);
|
||||
if (rb_is_red(parent))
|
||||
rb_set_black(parent);
|
||||
else {
|
||||
node = parent;
|
||||
parent = rb_parent(node);
|
||||
if (parent)
|
||||
continue;
|
||||
}
|
||||
break;
|
||||
}
|
||||
/* Case 3 - right rotate at sibling */
|
||||
sibling->rb_right = tmp1 = tmp2->rb_left;
|
||||
tmp2->rb_left = sibling;
|
||||
parent->rb_left = tmp2;
|
||||
if (tmp1)
|
||||
rb_set_parent_color(tmp1, sibling,
|
||||
RB_BLACK);
|
||||
augment_rotate(sibling, tmp2);
|
||||
tmp1 = sibling;
|
||||
sibling = tmp2;
|
||||
}
|
||||
/* Case 4 - left rotate at parent + color flips */
|
||||
parent->rb_left = tmp2 = sibling->rb_right;
|
||||
sibling->rb_right = parent;
|
||||
rb_set_parent_color(tmp1, sibling, RB_BLACK);
|
||||
if (tmp2)
|
||||
rb_set_parent(tmp2, parent);
|
||||
__rb_rotate_set_parents(parent, sibling, root,
|
||||
RB_BLACK);
|
||||
augment_rotate(parent, sibling);
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/* Non-inline version for rb_erase_augmented() use */
|
||||
void __rb_erase_color(struct rb_node *parent, struct rb_root *root,
|
||||
void (*augment_rotate)(struct rb_node *old, struct rb_node *new))
|
||||
{
|
||||
____rb_erase_color(parent, root, augment_rotate);
|
||||
}
|
||||
EXPORT_SYMBOL(__rb_erase_color);
|
||||
|
||||
/*
|
||||
* Non-augmented rbtree manipulation functions.
|
||||
*
|
||||
* We use dummy augmented callbacks here, and have the compiler optimize them
|
||||
* out of the rb_insert_color() and rb_erase() function definitions.
|
||||
*/
|
||||
|
||||
static inline void dummy_propagate(struct rb_node *node, struct rb_node *stop) {}
|
||||
static inline void dummy_copy(struct rb_node *old, struct rb_node *new) {}
|
||||
static inline void dummy_rotate(struct rb_node *old, struct rb_node *new) {}
|
||||
|
||||
static const struct rb_augment_callbacks dummy_callbacks = {
|
||||
dummy_propagate, dummy_copy, dummy_rotate
|
||||
};
|
||||
|
||||
void rb_insert_color(struct rb_node *node, struct rb_root *root)
|
||||
{
|
||||
struct rb_node *parent, *gparent;
|
||||
|
||||
while ((parent = rb_parent(node)) && rb_is_red(parent))
|
||||
{
|
||||
gparent = rb_parent(parent);
|
||||
|
||||
if (parent == gparent->rb_left)
|
||||
{
|
||||
{
|
||||
register struct rb_node *uncle = gparent->rb_right;
|
||||
if (uncle && rb_is_red(uncle))
|
||||
{
|
||||
rb_set_black(uncle);
|
||||
rb_set_black(parent);
|
||||
rb_set_red(gparent);
|
||||
node = gparent;
|
||||
continue;
|
||||
}
|
||||
}
|
||||
|
||||
if (parent->rb_right == node)
|
||||
{
|
||||
register struct rb_node *tmp;
|
||||
__rb_rotate_left(parent, root);
|
||||
tmp = parent;
|
||||
parent = node;
|
||||
node = tmp;
|
||||
}
|
||||
|
||||
rb_set_black(parent);
|
||||
rb_set_red(gparent);
|
||||
__rb_rotate_right(gparent, root);
|
||||
} else {
|
||||
{
|
||||
register struct rb_node *uncle = gparent->rb_left;
|
||||
if (uncle && rb_is_red(uncle))
|
||||
{
|
||||
rb_set_black(uncle);
|
||||
rb_set_black(parent);
|
||||
rb_set_red(gparent);
|
||||
node = gparent;
|
||||
continue;
|
||||
}
|
||||
}
|
||||
|
||||
if (parent->rb_left == node)
|
||||
{
|
||||
register struct rb_node *tmp;
|
||||
__rb_rotate_right(parent, root);
|
||||
tmp = parent;
|
||||
parent = node;
|
||||
node = tmp;
|
||||
}
|
||||
|
||||
rb_set_black(parent);
|
||||
rb_set_red(gparent);
|
||||
__rb_rotate_left(gparent, root);
|
||||
}
|
||||
}
|
||||
|
||||
rb_set_black(root->rb_node);
|
||||
}
|
||||
|
||||
static void __rb_erase_color(struct rb_node *node, struct rb_node *parent,
|
||||
struct rb_root *root)
|
||||
{
|
||||
struct rb_node *other;
|
||||
|
||||
while ((!node || rb_is_black(node)) && node != root->rb_node)
|
||||
{
|
||||
if (parent->rb_left == node)
|
||||
{
|
||||
other = parent->rb_right;
|
||||
if (rb_is_red(other))
|
||||
{
|
||||
rb_set_black(other);
|
||||
rb_set_red(parent);
|
||||
__rb_rotate_left(parent, root);
|
||||
other = parent->rb_right;
|
||||
}
|
||||
if ((!other->rb_left || rb_is_black(other->rb_left)) &&
|
||||
(!other->rb_right || rb_is_black(other->rb_right)))
|
||||
{
|
||||
rb_set_red(other);
|
||||
node = parent;
|
||||
parent = rb_parent(node);
|
||||
}
|
||||
else
|
||||
{
|
||||
if (!other->rb_right || rb_is_black(other->rb_right))
|
||||
{
|
||||
struct rb_node *o_left;
|
||||
if ((o_left = other->rb_left))
|
||||
rb_set_black(o_left);
|
||||
rb_set_red(other);
|
||||
__rb_rotate_right(other, root);
|
||||
other = parent->rb_right;
|
||||
}
|
||||
rb_set_color(other, rb_color(parent));
|
||||
rb_set_black(parent);
|
||||
if (other->rb_right)
|
||||
rb_set_black(other->rb_right);
|
||||
__rb_rotate_left(parent, root);
|
||||
node = root->rb_node;
|
||||
break;
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
other = parent->rb_left;
|
||||
if (rb_is_red(other))
|
||||
{
|
||||
rb_set_black(other);
|
||||
rb_set_red(parent);
|
||||
__rb_rotate_right(parent, root);
|
||||
other = parent->rb_left;
|
||||
}
|
||||
if ((!other->rb_left || rb_is_black(other->rb_left)) &&
|
||||
(!other->rb_right || rb_is_black(other->rb_right)))
|
||||
{
|
||||
rb_set_red(other);
|
||||
node = parent;
|
||||
parent = rb_parent(node);
|
||||
}
|
||||
else
|
||||
{
|
||||
if (!other->rb_left || rb_is_black(other->rb_left))
|
||||
{
|
||||
register struct rb_node *o_right;
|
||||
if ((o_right = other->rb_right))
|
||||
rb_set_black(o_right);
|
||||
rb_set_red(other);
|
||||
__rb_rotate_left(other, root);
|
||||
other = parent->rb_left;
|
||||
}
|
||||
rb_set_color(other, rb_color(parent));
|
||||
rb_set_black(parent);
|
||||
if (other->rb_left)
|
||||
rb_set_black(other->rb_left);
|
||||
__rb_rotate_right(parent, root);
|
||||
node = root->rb_node;
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
if (node)
|
||||
rb_set_black(node);
|
||||
__rb_insert(node, root, dummy_rotate);
|
||||
}
|
||||
EXPORT_SYMBOL(rb_insert_color);
|
||||
|
||||
void rb_erase(struct rb_node *node, struct rb_root *root)
|
||||
{
|
||||
struct rb_node *child, *parent;
|
||||
int color;
|
||||
|
||||
if (!node->rb_left)
|
||||
child = node->rb_right;
|
||||
else if (!node->rb_right)
|
||||
child = node->rb_left;
|
||||
else
|
||||
{
|
||||
struct rb_node *old = node, *left;
|
||||
|
||||
node = node->rb_right;
|
||||
while ((left = node->rb_left) != NULL)
|
||||
node = left;
|
||||
child = node->rb_right;
|
||||
parent = rb_parent(node);
|
||||
color = rb_color(node);
|
||||
|
||||
if (child)
|
||||
rb_set_parent(child, parent);
|
||||
if (parent == old) {
|
||||
parent->rb_right = child;
|
||||
parent = node;
|
||||
} else
|
||||
parent->rb_left = child;
|
||||
|
||||
node->rb_parent_color = old->rb_parent_color;
|
||||
node->rb_right = old->rb_right;
|
||||
node->rb_left = old->rb_left;
|
||||
|
||||
if (rb_parent(old))
|
||||
{
|
||||
if (rb_parent(old)->rb_left == old)
|
||||
rb_parent(old)->rb_left = node;
|
||||
else
|
||||
rb_parent(old)->rb_right = node;
|
||||
} else
|
||||
root->rb_node = node;
|
||||
|
||||
rb_set_parent(old->rb_left, node);
|
||||
if (old->rb_right)
|
||||
rb_set_parent(old->rb_right, node);
|
||||
goto color;
|
||||
}
|
||||
|
||||
parent = rb_parent(node);
|
||||
color = rb_color(node);
|
||||
|
||||
if (child)
|
||||
rb_set_parent(child, parent);
|
||||
if (parent)
|
||||
{
|
||||
if (parent->rb_left == node)
|
||||
parent->rb_left = child;
|
||||
else
|
||||
parent->rb_right = child;
|
||||
}
|
||||
else
|
||||
root->rb_node = child;
|
||||
|
||||
color:
|
||||
if (color == RB_BLACK)
|
||||
__rb_erase_color(child, parent, root);
|
||||
struct rb_node *rebalance;
|
||||
rebalance = __rb_erase_augmented(node, root, &dummy_callbacks);
|
||||
if (rebalance)
|
||||
____rb_erase_color(rebalance, root, dummy_rotate);
|
||||
}
|
||||
EXPORT_SYMBOL(rb_erase);
|
||||
|
||||
/*
|
||||
* Augmented rbtree manipulation functions.
|
||||
*
|
||||
* This instantiates the same __always_inline functions as in the non-augmented
|
||||
* case, but this time with user-defined callbacks.
|
||||
*/
|
||||
|
||||
void __rb_insert_augmented(struct rb_node *node, struct rb_root *root,
|
||||
void (*augment_rotate)(struct rb_node *old, struct rb_node *new))
|
||||
{
|
||||
__rb_insert(node, root, augment_rotate);
|
||||
}
|
||||
EXPORT_SYMBOL(__rb_insert_augmented);
|
||||
|
||||
/*
|
||||
* This function returns the first node (in sort order) of the tree.
|
||||
*/
|
||||
struct rb_node *rb_first(struct rb_root *root)
|
||||
struct rb_node *rb_first(const struct rb_root *root)
|
||||
{
|
||||
struct rb_node *n;
|
||||
|
||||
@ -289,8 +418,9 @@ struct rb_node *rb_first(struct rb_root *root)
|
||||
n = n->rb_left;
|
||||
return n;
|
||||
}
|
||||
EXPORT_SYMBOL(rb_first);
|
||||
|
||||
struct rb_node *rb_last(struct rb_root *root)
|
||||
struct rb_node *rb_last(const struct rb_root *root)
|
||||
{
|
||||
struct rb_node *n;
|
||||
|
||||
@ -301,58 +431,68 @@ struct rb_node *rb_last(struct rb_root *root)
|
||||
n = n->rb_right;
|
||||
return n;
|
||||
}
|
||||
EXPORT_SYMBOL(rb_last);
|
||||
|
||||
struct rb_node *rb_next(struct rb_node *node)
|
||||
struct rb_node *rb_next(const struct rb_node *node)
|
||||
{
|
||||
struct rb_node *parent;
|
||||
|
||||
if (rb_parent(node) == node)
|
||||
if (RB_EMPTY_NODE(node))
|
||||
return NULL;
|
||||
|
||||
/* If we have a right-hand child, go down and then left as far
|
||||
as we can. */
|
||||
/*
|
||||
* If we have a right-hand child, go down and then left as far
|
||||
* as we can.
|
||||
*/
|
||||
if (node->rb_right) {
|
||||
node = node->rb_right;
|
||||
node = node->rb_right;
|
||||
while (node->rb_left)
|
||||
node=node->rb_left;
|
||||
return node;
|
||||
return (struct rb_node *)node;
|
||||
}
|
||||
|
||||
/* No right-hand children. Everything down and left is
|
||||
smaller than us, so any 'next' node must be in the general
|
||||
direction of our parent. Go up the tree; any time the
|
||||
ancestor is a right-hand child of its parent, keep going
|
||||
up. First time it's a left-hand child of its parent, said
|
||||
parent is our 'next' node. */
|
||||
/*
|
||||
* No right-hand children. Everything down and left is smaller than us,
|
||||
* so any 'next' node must be in the general direction of our parent.
|
||||
* Go up the tree; any time the ancestor is a right-hand child of its
|
||||
* parent, keep going up. First time it's a left-hand child of its
|
||||
* parent, said parent is our 'next' node.
|
||||
*/
|
||||
while ((parent = rb_parent(node)) && node == parent->rb_right)
|
||||
node = parent;
|
||||
|
||||
return parent;
|
||||
}
|
||||
EXPORT_SYMBOL(rb_next);
|
||||
|
||||
struct rb_node *rb_prev(struct rb_node *node)
|
||||
struct rb_node *rb_prev(const struct rb_node *node)
|
||||
{
|
||||
struct rb_node *parent;
|
||||
|
||||
if (rb_parent(node) == node)
|
||||
if (RB_EMPTY_NODE(node))
|
||||
return NULL;
|
||||
|
||||
/* If we have a left-hand child, go down and then right as far
|
||||
as we can. */
|
||||
/*
|
||||
* If we have a left-hand child, go down and then right as far
|
||||
* as we can.
|
||||
*/
|
||||
if (node->rb_left) {
|
||||
node = node->rb_left;
|
||||
node = node->rb_left;
|
||||
while (node->rb_right)
|
||||
node=node->rb_right;
|
||||
return node;
|
||||
return (struct rb_node *)node;
|
||||
}
|
||||
|
||||
/* No left-hand children. Go up till we find an ancestor which
|
||||
is a right-hand child of its parent */
|
||||
/*
|
||||
* No left-hand children. Go up till we find an ancestor which
|
||||
* is a right-hand child of its parent.
|
||||
*/
|
||||
while ((parent = rb_parent(node)) && node == parent->rb_left)
|
||||
node = parent;
|
||||
|
||||
return parent;
|
||||
}
|
||||
EXPORT_SYMBOL(rb_prev);
|
||||
|
||||
void rb_replace_node(struct rb_node *victim, struct rb_node *new,
|
||||
struct rb_root *root)
|
||||
@ -360,14 +500,7 @@ void rb_replace_node(struct rb_node *victim, struct rb_node *new,
|
||||
struct rb_node *parent = rb_parent(victim);
|
||||
|
||||
/* Set the surrounding nodes to point to the replacement */
|
||||
if (parent) {
|
||||
if (victim == parent->rb_left)
|
||||
parent->rb_left = new;
|
||||
else
|
||||
parent->rb_right = new;
|
||||
} else {
|
||||
root->rb_node = new;
|
||||
}
|
||||
__rb_change_child(victim, new, parent, root);
|
||||
if (victim->rb_left)
|
||||
rb_set_parent(victim->rb_left, new);
|
||||
if (victim->rb_right)
|
||||
@ -376,3 +509,44 @@ void rb_replace_node(struct rb_node *victim, struct rb_node *new,
|
||||
/* Copy the pointers/colour from the victim to the replacement */
|
||||
*new = *victim;
|
||||
}
|
||||
EXPORT_SYMBOL(rb_replace_node);
|
||||
|
||||
static struct rb_node *rb_left_deepest_node(const struct rb_node *node)
|
||||
{
|
||||
for (;;) {
|
||||
if (node->rb_left)
|
||||
node = node->rb_left;
|
||||
else if (node->rb_right)
|
||||
node = node->rb_right;
|
||||
else
|
||||
return (struct rb_node *)node;
|
||||
}
|
||||
}
|
||||
|
||||
struct rb_node *rb_next_postorder(const struct rb_node *node)
|
||||
{
|
||||
const struct rb_node *parent;
|
||||
if (!node)
|
||||
return NULL;
|
||||
parent = rb_parent(node);
|
||||
|
||||
/* If we're sitting on node, we've already seen our children */
|
||||
if (parent && node == parent->rb_left && parent->rb_right) {
|
||||
/* If we are the parent's left node, go to the parent's right
|
||||
* node then all the way down to the left */
|
||||
return rb_left_deepest_node(parent->rb_right);
|
||||
} else
|
||||
/* Otherwise we are the parent's right node, and the parent
|
||||
* should be next */
|
||||
return (struct rb_node *)parent;
|
||||
}
|
||||
EXPORT_SYMBOL(rb_next_postorder);
|
||||
|
||||
struct rb_node *rb_first_postorder(const struct rb_root *root)
|
||||
{
|
||||
if (!root->rb_node)
|
||||
return NULL;
|
||||
|
||||
return rb_left_deepest_node(root->rb_node);
|
||||
}
|
||||
EXPORT_SYMBOL(rb_first_postorder);
|
||||
|
Loading…
Reference in New Issue
Block a user