1 /*-
2  * Copyright (c) 2020 Mellanox Technologies, Ltd.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice unmodified, this list of conditions, and the following
10  *    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 ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 #ifndef	_LINUXKPI_LINUX_XARRAY_H_
29 #define	_LINUXKPI_LINUX_XARRAY_H_
30 
31 #include <linux/gfp.h>
32 #include <linux/radix-tree.h>
33 #include <linux/err.h>
34 #include <linux/kconfig.h>
35 
36 #include <sys/lock.h>
37 #include <sys/mutex.h>
38 
39 #define	XA_LIMIT(min, max) \
40     ({ CTASSERT((min) == 0); (uint32_t)(max); })
41 
42 #define	XA_FLAGS_ALLOC (1U << 0)
43 #define	XA_FLAGS_LOCK_IRQ (1U << 1)
44 #define	XA_FLAGS_ALLOC1 (1U << 2)
45 
46 #define	XA_ERROR(x) \
47 	ERR_PTR(x)
48 
49 #define	xa_is_err(x) \
50 	IS_ERR(x)
51 
52 #define	xa_limit_32b XA_LIMIT(0, 0xFFFFFFFF)
53 
54 #define	XA_ASSERT_LOCKED(xa) mtx_assert(&(xa)->mtx, MA_OWNED)
55 #define	xa_lock(xa) mtx_lock(&(xa)->mtx)
56 #define	xa_unlock(xa) mtx_unlock(&(xa)->mtx)
57 
58 struct xarray {
59 	struct radix_tree_root root;
60 	struct mtx mtx;		/* internal mutex */
61 	uint32_t flags;		/* see XA_FLAGS_XXX */
62 };
63 
64 /*
65  * Extensible arrays API implemented as a wrapper
66  * around the radix tree implementation.
67  */
68 void *xa_erase(struct xarray *, uint32_t);
69 void *xa_load(struct xarray *, uint32_t);
70 int xa_alloc(struct xarray *, uint32_t *, void *, uint32_t, gfp_t);
71 int xa_alloc_cyclic(struct xarray *, uint32_t *, void *, uint32_t, uint32_t *, gfp_t);
72 int xa_insert(struct xarray *, uint32_t, void *, gfp_t);
73 void *xa_store(struct xarray *, uint32_t, void *, gfp_t);
74 void xa_init_flags(struct xarray *, uint32_t);
75 bool xa_empty(struct xarray *);
76 void xa_destroy(struct xarray *);
77 void *xa_next(struct xarray *, unsigned long *, bool);
78 
79 #define	xa_for_each(xa, index, entry) \
80 	for ((entry) = NULL, (index) = 0; \
81 	     ((entry) = xa_next(xa, &index, (entry) != NULL)) != NULL; )
82 
83 /*
84  * Unlocked version of functions above.
85  */
86 void *__xa_erase(struct xarray *, uint32_t);
87 int __xa_alloc(struct xarray *, uint32_t *, void *, uint32_t, gfp_t);
88 int __xa_alloc_cyclic(struct xarray *, uint32_t *, void *, uint32_t, uint32_t *, gfp_t);
89 int __xa_insert(struct xarray *, uint32_t, void *, gfp_t);
90 void *__xa_store(struct xarray *, uint32_t, void *, gfp_t);
91 bool __xa_empty(struct xarray *);
92 void *__xa_next(struct xarray *, unsigned long *, bool);
93 
94 #define	xa_store_irq(xa, index, ptr, gfp) \
95 	xa_store((xa), (index), (ptr), (gfp))
96 
97 #define	xa_erase_irq(xa, index) \
98 	xa_erase((xa), (index))
99 
100 #define	xa_lock_irqsave(xa, flags) \
101 	do { \
102 		xa_lock((xa)); \
103 		flags = 0; \
104 	} while (0)
105 
106 #define	xa_unlock_irqrestore(xa, flags) \
107 	do { \
108 		xa_unlock((xa)); \
109 		flags == 0; \
110 	} while (0)
111 
112 static inline int
113 xa_err(void *ptr)
114 {
115 	return (PTR_ERR_OR_ZERO(ptr));
116 }
117 
118 static inline void
119 xa_init(struct xarray *xa)
120 {
121 	xa_init_flags(xa, 0);
122 }
123 
124 static inline void *
125 xa_mk_value(unsigned long v)
126 {
127 	unsigned long r = (v << 1) | 1;
128 
129 	return ((void *)r);
130 }
131 
132 static inline bool
133 xa_is_value(const void *e)
134 {
135 	unsigned long v = (unsigned long)e;
136 
137 	return (v & 1);
138 }
139 
140 static inline unsigned long
141 xa_to_value(const void *e)
142 {
143 	unsigned long v = (unsigned long)e;
144 
145 	return (v >> 1);
146 }
147 #endif		/* _LINUXKPI_LINUX_XARRAY_H_ */
148