1/*-
2 * Copyright (c) 2010 Isilon Systems, Inc.
3 * Copyright (c) 2010 iX Systems, Inc.
4 * Copyright (c) 2010 Panasas, Inc.
5 * Copyright (c) 2013-2018 Mellanox Technologies, Ltd.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice unmodified, this list of conditions, and the following
13 *    disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 *
29 * $FreeBSD$
30 */
31#ifndef	_LINUX_RADIX_TREE_H_
32#define	_LINUX_RADIX_TREE_H_
33
34#include <linux/types.h>
35
36#define	RADIX_TREE_MAP_SHIFT	6
37#define	RADIX_TREE_MAP_SIZE	(1UL << RADIX_TREE_MAP_SHIFT)
38#define	RADIX_TREE_MAP_MASK	(RADIX_TREE_MAP_SIZE - 1UL)
39#define	RADIX_TREE_MAX_HEIGHT \
40	howmany(sizeof(long) * NBBY, RADIX_TREE_MAP_SHIFT)
41
42#define	RADIX_TREE_ENTRY_MASK 3UL
43#define	RADIX_TREE_EXCEPTIONAL_ENTRY 2UL
44#define	RADIX_TREE_EXCEPTIONAL_SHIFT 2
45
46struct radix_tree_node {
47	void		*slots[RADIX_TREE_MAP_SIZE];
48	int		count;
49};
50
51struct radix_tree_root {
52	struct radix_tree_node	*rnode;
53	gfp_t			gfp_mask;
54	int			height;
55};
56
57struct radix_tree_iter {
58	unsigned long index;
59};
60
61#define	RADIX_TREE_INIT(mask)						\
62	    { .rnode = NULL, .gfp_mask = mask, .height = 0 };
63#define	INIT_RADIX_TREE(root, mask)					\
64	    { (root)->rnode = NULL; (root)->gfp_mask = mask; (root)->height = 0; }
65#define	RADIX_TREE(name, mask)						\
66	    struct radix_tree_root name = RADIX_TREE_INIT(mask)
67
68#define	radix_tree_for_each_slot(slot, root, iter, start) \
69	for ((iter)->index = (start);			  \
70	     radix_tree_iter_find(root, iter, &(slot)); (iter)->index++)
71
72static inline int
73radix_tree_exception(void *arg)
74{
75	return ((uintptr_t)arg & RADIX_TREE_ENTRY_MASK);
76}
77
78void	*radix_tree_lookup(struct radix_tree_root *, unsigned long);
79void	*radix_tree_delete(struct radix_tree_root *, unsigned long);
80int	radix_tree_insert(struct radix_tree_root *, unsigned long, void *);
81bool	radix_tree_iter_find(struct radix_tree_root *, struct radix_tree_iter *, void ***);
82void	radix_tree_iter_delete(struct radix_tree_root *, struct radix_tree_iter *, void **);
83
84#endif	/* _LINUX_RADIX_TREE_H_ */
85