xref: /freebsd/sys/compat/linuxkpi/common/include/linux/radix-tree.h (revision a689bfa4e25af8307709dc12f75b0e02a65abf18)
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_MAX_TAGS	3
42 #define	RADIX_TREE_TAG_LONGS	RADIX_TREE_MAP_SIZE
43 
44 #define	RADIX_TREE_ENTRY_MASK 3UL
45 #define	RADIX_TREE_EXCEPTIONAL_ENTRY 2UL
46 #define	RADIX_TREE_EXCEPTIONAL_SHIFT 2
47 
48 #define	RADIX_TREE_ITER_TAG_MASK	0x0f
49 #define	RADIX_TREE_ITER_TAGGED		0x10
50 
51 struct radix_tree_node {
52 	void		*slots[RADIX_TREE_MAP_SIZE];
53 	unsigned long	tags[RADIX_TREE_MAX_TAGS][RADIX_TREE_TAG_LONGS];
54 	int		count;
55 };
56 
57 struct radix_tree_root {
58 	struct radix_tree_node	*rnode;
59 	gfp_t			gfp_mask;
60 	int			height;
61 	/* Linux stores root tags inside `gfp_mask`. */
62 	unsigned long		tags[RADIX_TREE_MAX_TAGS];
63 };
64 
65 struct radix_tree_iter {
66 	unsigned long index;
67 };
68 
69 #define	RADIX_TREE_INIT(mask)						\
70 	    { .rnode = NULL, .gfp_mask = mask, .height = 0 };
71 #define	INIT_RADIX_TREE(root, mask)					\
72 	    { (root)->rnode = NULL; (root)->gfp_mask = mask; (root)->height = 0; }
73 #define	RADIX_TREE(name, mask)						\
74 	    struct radix_tree_root name = RADIX_TREE_INIT(mask)
75 
76 #define	radix_tree_for_each_slot(slot, root, iter, start)		\
77 	for ((iter)->index = (start);					\
78 	     radix_tree_iter_find(root, iter, &(slot), 0);		\
79 	     (iter)->index++)
80 
81 #define	radix_tree_for_each_slot_tagged(slot, root, iter, start, tag)	\
82 	for ((iter)->index = (start);					\
83 	     radix_tree_iter_find(root, iter, &(slot),			\
84 	         RADIX_TREE_ITER_TAGGED | tag);				\
85 	     (iter)->index++)
86 
87 static inline void *
88 radix_tree_deref_slot(void **slot)
89 {
90 	return (*slot);
91 }
92 
93 static inline int
94 radix_tree_exception(void *arg)
95 {
96 	return ((uintptr_t)arg & RADIX_TREE_ENTRY_MASK);
97 }
98 
99 void	*radix_tree_lookup(const struct radix_tree_root *, unsigned long);
100 void	*radix_tree_delete(struct radix_tree_root *, unsigned long);
101 int	radix_tree_insert(struct radix_tree_root *, unsigned long, void *);
102 int	radix_tree_store(struct radix_tree_root *, unsigned long, void **);
103 bool	radix_tree_iter_find(const struct radix_tree_root *, struct radix_tree_iter *, void ***, int);
104 void	radix_tree_iter_delete(struct radix_tree_root *, struct radix_tree_iter *, void **);
105 void	*radix_tree_tag_set(struct radix_tree_root *root, unsigned long index, unsigned int tag);
106 void	*radix_tree_tag_clear(struct radix_tree_root *root, unsigned long index, unsigned int tag);
107 int	radix_tree_tagged(const struct radix_tree_root *root, unsigned int tag);
108 unsigned int	radix_tree_gang_lookup(const struct radix_tree_root *root, void **results, unsigned long first_index, unsigned int max_items);
109 unsigned int	radix_tree_gang_lookup_tag(const struct radix_tree_root *root, void **results, unsigned long first_index, unsigned int max_items, unsigned int tag);
110 
111 #endif	/* _LINUXKPI_LINUX_RADIX_TREE_H_ */
112