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
46 struct radix_tree_node {
47 void *slots[RADIX_TREE_MAP_SIZE];
48 int count;
49 };
50
51 struct radix_tree_root {
52 struct radix_tree_node *rnode;
53 gfp_t gfp_mask;
54 int height;
55 };
56
57 struct 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
72 static inline int
radix_tree_exception(void * arg)73 radix_tree_exception(void *arg)
74 {
75 return ((uintptr_t)arg & RADIX_TREE_ENTRY_MASK);
76 }
77
78 void *radix_tree_lookup(struct radix_tree_root *, unsigned long);
79 void *radix_tree_delete(struct radix_tree_root *, unsigned long);
80 int radix_tree_insert(struct radix_tree_root *, unsigned long, void *);
81 bool radix_tree_iter_find(struct radix_tree_root *, struct radix_tree_iter *, void ***);
82 void radix_tree_iter_delete(struct radix_tree_root *, struct radix_tree_iter *, void **);
83
84 #endif /* _LINUX_RADIX_TREE_H_ */
85