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 #ifndef	_LINUXKPI_LINUX_XARRAY_H_
27 #define	_LINUXKPI_LINUX_XARRAY_H_
28 
29 #include <linux/gfp.h>
30 #include <linux/radix-tree.h>
31 #include <linux/err.h>
32 #include <linux/kconfig.h>
33 
34 #include <sys/lock.h>
35 #include <sys/mutex.h>
36 
37 #define	XA_LIMIT(min, max) \
38     ({ CTASSERT((min) == 0); (uint32_t)(max); })
39 
40 #define	XA_FLAGS_ALLOC (1U << 0)
41 #define	XA_FLAGS_LOCK_IRQ (1U << 1)
42 #define	XA_FLAGS_ALLOC1 (1U << 2)
43 
44 #define	XA_ERROR(x) \
45 	ERR_PTR(x)
46 
47 #define	xa_is_err(x) \
48 	IS_ERR(x)
49 
50 #define	xa_limit_32b XA_LIMIT(0, 0xFFFFFFFF)
51 
52 #define	XA_ASSERT_LOCKED(xa) mtx_assert(&(xa)->mtx, MA_OWNED)
53 #define	xa_lock(xa) mtx_lock(&(xa)->mtx)
54 #define	xa_unlock(xa) mtx_unlock(&(xa)->mtx)
55 
56 struct xarray {
57 	struct radix_tree_root root;
58 	struct mtx mtx;		/* internal mutex */
59 	uint32_t flags;		/* see XA_FLAGS_XXX */
60 };
61 
62 /*
63  * Extensible arrays API implemented as a wrapper
64  * around the radix tree implementation.
65  */
66 void *xa_erase(struct xarray *, uint32_t);
67 void *xa_load(struct xarray *, uint32_t);
68 int xa_alloc(struct xarray *, uint32_t *, void *, uint32_t, gfp_t);
69 int xa_alloc_cyclic(struct xarray *, uint32_t *, void *, uint32_t, uint32_t *, gfp_t);
70 int xa_insert(struct xarray *, uint32_t, void *, gfp_t);
71 void *xa_store(struct xarray *, uint32_t, void *, gfp_t);
72 void xa_init_flags(struct xarray *, uint32_t);
73 bool xa_empty(struct xarray *);
74 void xa_destroy(struct xarray *);
75 void *xa_next(struct xarray *, unsigned long *, bool);
76 
77 #define	xa_for_each(xa, index, entry) \
78 	for ((entry) = NULL, (index) = 0; \
79 	     ((entry) = xa_next(xa, &index, (entry) != NULL)) != NULL; )
80 
81 /*
82  * Unlocked version of functions above.
83  */
84 void *__xa_erase(struct xarray *, uint32_t);
85 int __xa_alloc(struct xarray *, uint32_t *, void *, uint32_t, gfp_t);
86 int __xa_alloc_cyclic(struct xarray *, uint32_t *, void *, uint32_t, uint32_t *, gfp_t);
87 int __xa_insert(struct xarray *, uint32_t, void *, gfp_t);
88 void *__xa_store(struct xarray *, uint32_t, void *, gfp_t);
89 bool __xa_empty(struct xarray *);
90 void *__xa_next(struct xarray *, unsigned long *, bool);
91 
92 #define	xa_store_irq(xa, index, ptr, gfp) \
93 	xa_store((xa), (index), (ptr), (gfp))
94 
95 #define	xa_erase_irq(xa, index) \
96 	xa_erase((xa), (index))
97 
98 #define	xa_lock_irq(xa)		xa_lock(xa)
99 #define	xa_unlock_irq(xa)	xa_unlock(xa)
100 
101 #define	xa_lock_irqsave(xa, flags) \
102 	do { \
103 		xa_lock((xa)); \
104 		flags = 0; \
105 	} while (0)
106 
107 #define	xa_unlock_irqrestore(xa, flags) \
108 	do { \
109 		xa_unlock((xa)); \
110 		flags == 0; \
111 	} while (0)
112 
113 static inline int
114 xa_err(void *ptr)
115 {
116 	return (PTR_ERR_OR_ZERO(ptr));
117 }
118 
119 static inline void
120 xa_init(struct xarray *xa)
121 {
122 	xa_init_flags(xa, 0);
123 }
124 
125 static inline void *
126 xa_mk_value(unsigned long v)
127 {
128 	unsigned long r = (v << 1) | 1;
129 
130 	return ((void *)r);
131 }
132 
133 static inline bool
134 xa_is_value(const void *e)
135 {
136 	unsigned long v = (unsigned long)e;
137 
138 	return (v & 1);
139 }
140 
141 static inline unsigned long
142 xa_to_value(const void *e)
143 {
144 	unsigned long v = (unsigned long)e;
145 
146 	return (v >> 1);
147 }
148 #endif		/* _LINUXKPI_LINUX_XARRAY_H_ */
149