vm_radix.h revision 238395 
1/*
2 * Copyright (c) 2011 Jeffrey Roberson <jeff@freebsd.org>
3 * Copyright (c) 2008 Mayur Shardul <mayur.shardul@gmail.com>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 */
28
29#ifndef _VM_RADIX_H_
30#define _VM_RADIX_H_
31
32/*
33 * Radix tree root.  The height and pointer are set together to permit
34 * coherent lookups while the root is modified.
35 */
36struct vm_radix {
37	uintptr_t	rt_root;		/* root + height */
38};
39
40#ifdef _KERNEL
41
42void	vm_radix_init(void);
43int 	vm_radix_insert(struct vm_radix *, vm_pindex_t, void *);
44void	*vm_radix_lookup(struct vm_radix *, vm_pindex_t);
45int	vm_radix_lookupn(struct vm_radix *, vm_pindex_t, vm_pindex_t, void **,
46	    int, vm_pindex_t *, u_int *);
47void	*vm_radix_lookup_le(struct vm_radix *, vm_pindex_t);
48void	vm_radix_reclaim_allnodes(struct vm_radix *);
49void	vm_radix_remove(struct vm_radix *, vm_pindex_t);
50
51/*
52 * Look up any entry at a position greater or equal to index.
53 */
54static inline void *
55vm_radix_lookup_ge(struct vm_radix *rtree, vm_pindex_t index)
56{
57	void *val;
58	u_int dummy;
59
60	if (vm_radix_lookupn(rtree, index, 0, &val, 1, &index, &dummy))
61		return (val);
62	return (NULL);
63}
64
65#endif /* _KERNEL */
66#endif /* !_VM_RADIX_H_ */
67