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	_LINUX_XARRAY_H_
29 #define	_LINUX_XARRAY_H_
30 
31 #include <linux/gfp.h>
32 #include <linux/radix-tree.h>
33 #include <linux/err.h>
34 
35 #include <sys/lock.h>
36 #include <sys/mutex.h>
37 
38 #define	XA_LIMIT(min, max) \
39     ({ CTASSERT((min) == 0); (uint32_t)(max); })
40 
41 #define	XA_FLAGS_ALLOC (1U << 0)
42 #define	XA_FLAGS_LOCK_IRQ (1U << 1)
43 
44 #define	XA_ERROR(x) \
45 	ERR_PTR(x)
46 
47 #define	xa_limit_32b XA_LIMIT(0, 0xFFFFFFFF)
48 
49 #define	XA_ASSERT_LOCKED(xa) mtx_assert(&(xa)->mtx, MA_OWNED)
50 #define	xa_lock(xa) mtx_lock(&(xa)->mtx)
51 #define	xa_unlock(xa) mtx_unlock(&(xa)->mtx)
52 
53 struct xarray {
54 	struct radix_tree_root root;
55 	struct mtx mtx;		/* internal mutex */
56 };
57 
58 /*
59  * Extensible arrays API implemented as a wrapper
60  * around the radix tree implementation.
61  */
62 void *xa_erase(struct xarray *, uint32_t);
63 void *xa_load(struct xarray *, uint32_t);
64 int xa_alloc(struct xarray *, uint32_t *, void *, uint32_t, gfp_t);
65 int xa_alloc_cyclic(struct xarray *, uint32_t *, void *, uint32_t, uint32_t *, gfp_t);
66 int xa_insert(struct xarray *, uint32_t, void *, gfp_t);
67 void *xa_store(struct xarray *, uint32_t, void *, gfp_t);
68 void xa_init_flags(struct xarray *, uint32_t);
69 bool xa_empty(struct xarray *);
70 void xa_destroy(struct xarray *);
71 void *xa_next(struct xarray *, unsigned long *, bool);
72 
73 #define	xa_for_each(xa, index, entry) \
74 	for ((entry) = NULL, (index) = 0; \
75 	     ((entry) = xa_next(xa, &index, (entry) != NULL)) != NULL; )
76 
77 /*
78  * Unlocked version of functions above.
79  */
80 void *__xa_erase(struct xarray *, uint32_t);
81 int __xa_alloc(struct xarray *, uint32_t *, void *, uint32_t, gfp_t);
82 int __xa_alloc_cyclic(struct xarray *, uint32_t *, void *, uint32_t, uint32_t *, gfp_t);
83 int __xa_insert(struct xarray *, uint32_t, void *, gfp_t);
84 void *__xa_store(struct xarray *, uint32_t, void *, gfp_t);
85 bool __xa_empty(struct xarray *);
86 void *__xa_next(struct xarray *, unsigned long *, bool);
87 
88 static inline int
89 xa_err(void *ptr)
90 {
91 	return (PTR_ERR_OR_ZERO(ptr));
92 }
93 
94 static inline void
95 xa_init(struct xarray *xa)
96 {
97 	xa_init_flags(xa, 0);
98 }
99 
100 #endif		/* _LINUX_XARRAY_H_ */
101