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 #ifndef _LINUXKPI_LINUX_RADIX_TREE_H_
30 #define _LINUXKPI_LINUX_RADIX_TREE_H_
31
32 #include <linux/types.h>
33
34 #define RADIX_TREE_MAP_SHIFT 6
35 #define RADIX_TREE_MAP_SIZE (1UL << RADIX_TREE_MAP_SHIFT)
36 #define RADIX_TREE_MAP_MASK (RADIX_TREE_MAP_SIZE - 1UL)
37 #define RADIX_TREE_MAX_HEIGHT \
38 howmany(sizeof(long) * NBBY, RADIX_TREE_MAP_SHIFT)
39
40 #define RADIX_TREE_ENTRY_MASK 3UL
41 #define RADIX_TREE_EXCEPTIONAL_ENTRY 2UL
42 #define RADIX_TREE_EXCEPTIONAL_SHIFT 2
43
44 struct radix_tree_node {
45 void *slots[RADIX_TREE_MAP_SIZE];
46 int count;
47 };
48
49 struct radix_tree_root {
50 struct radix_tree_node *rnode;
51 gfp_t gfp_mask;
52 int height;
53 };
54
55 struct radix_tree_iter {
56 unsigned long index;
57 };
58
59 #define RADIX_TREE_INIT(mask) \
60 { .rnode = NULL, .gfp_mask = mask, .height = 0 };
61 #define INIT_RADIX_TREE(root, mask) \
62 { (root)->rnode = NULL; (root)->gfp_mask = mask; (root)->height = 0; }
63 #define RADIX_TREE(name, mask) \
64 struct radix_tree_root name = RADIX_TREE_INIT(mask)
65
66 #define radix_tree_for_each_slot(slot, root, iter, start) \
67 for ((iter)->index = (start); \
68 radix_tree_iter_find(root, iter, &(slot)); (iter)->index++)
69
70 static inline int
radix_tree_exception(void * arg)71 radix_tree_exception(void *arg)
72 {
73 return ((uintptr_t)arg & RADIX_TREE_ENTRY_MASK);
74 }
75
76 void *radix_tree_lookup(struct radix_tree_root *, unsigned long);
77 void *radix_tree_delete(struct radix_tree_root *, unsigned long);
78 int radix_tree_insert(struct radix_tree_root *, unsigned long, void *);
79 int radix_tree_store(struct radix_tree_root *, unsigned long, void **);
80 bool radix_tree_iter_find(struct radix_tree_root *, struct radix_tree_iter *, void ***);
81 void radix_tree_iter_delete(struct radix_tree_root *, struct radix_tree_iter *, void **);
82
83 #endif /* _LINUXKPI_LINUX_RADIX_TREE_H_ */
84