xref: /freebsd/sys/compat/linuxkpi/common/include/linux/radix-tree.h (revision 2cd53241538632fa1c731fbf85384b785e77bd1b)
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/rcupdate.h>
33 #include <linux/types.h>
34 
35 #define	RADIX_TREE_MAP_SHIFT	6
36 #define	RADIX_TREE_MAP_SIZE	(1UL << RADIX_TREE_MAP_SHIFT)
37 #define	RADIX_TREE_MAP_MASK	(RADIX_TREE_MAP_SIZE - 1UL)
38 #define	RADIX_TREE_MAX_HEIGHT \
39 	howmany(sizeof(long) * NBBY, RADIX_TREE_MAP_SHIFT)
40 
41 #define	RADIX_TREE_ENTRY_MASK 3UL
42 #define	RADIX_TREE_EXCEPTIONAL_ENTRY 2UL
43 #define	RADIX_TREE_EXCEPTIONAL_SHIFT 2
44 
45 struct radix_tree_node {
46 	void		*slots[RADIX_TREE_MAP_SIZE];
47 	int		count;
48 };
49 
50 struct radix_tree_root {
51 	struct radix_tree_node	*rnode;
52 	gfp_t			gfp_mask;
53 	int			height;
54 };
55 
56 struct radix_tree_iter {
57 	unsigned long index;
58 };
59 
60 #define	RADIX_TREE_INIT(mask)						\
61 	    { .rnode = NULL, .gfp_mask = mask, .height = 0 };
62 #define	INIT_RADIX_TREE(root, mask)					\
63 	    { (root)->rnode = NULL; (root)->gfp_mask = mask; (root)->height = 0; }
64 #define	RADIX_TREE(name, mask)						\
65 	    struct radix_tree_root name = RADIX_TREE_INIT(mask)
66 
67 #define	radix_tree_for_each_slot(slot, root, iter, start) \
68 	for ((iter)->index = (start);			  \
69 	     radix_tree_iter_find(root, iter, &(slot)); (iter)->index++)
70 
71 static inline int
72 radix_tree_exception(void *arg)
73 {
74 	return ((uintptr_t)arg & RADIX_TREE_ENTRY_MASK);
75 }
76 
77 void	*radix_tree_lookup(struct radix_tree_root *, unsigned long);
78 void	*radix_tree_delete(struct radix_tree_root *, unsigned long);
79 int	radix_tree_insert(struct radix_tree_root *, unsigned long, void *);
80 int	radix_tree_store(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	/* _LINUXKPI_LINUX_RADIX_TREE_H_ */
85