xref: /netbsd-src/sys/external/bsd/drm2/include/linux/xarray.h (revision e2654e7d8c59167303b7c2dc20fea82387aecffc)
1 /*	$NetBSD: xarray.h,v 1.9 2021/12/19 12:05:25 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (c) 2020 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #ifndef	_LINUX_XARRAY_H_
30 #define	_LINUX_XARRAY_H_
31 
32 #include <sys/rbtree.h>
33 
34 #include <linux/slab.h>
35 
36 struct xarray;
37 struct xa_limit;
38 
39 struct xa_limit {
40 	uint32_t	max;
41 	uint32_t	min;
42 };
43 
44 struct xarray {
45 	kmutex_t		xa_lock;
46 	struct rb_tree		xa_tree;
47 	gfp_t			xa_gfp;
48 };
49 
50 #define	xa_for_each(XA, INDEX, ENTRY)					      \
51 	for ((INDEX) = 0, (ENTRY) = xa_find((XA), &(INDEX), ULONG_MAX, -1);   \
52 		(ENTRY) != NULL;					      \
53 		(ENTRY) = xa_find_after((XA), &(INDEX), ULONG_MAX, -1))
54 
55 #define	XA_ERROR(error)	((void *)(((uintptr_t)error << 2) | 2))
56 
57 static inline int
xa_err(void * cookie)58 xa_err(void *cookie)
59 {
60 
61 	if (((uintptr_t)cookie & 3) != 2)
62 		return 0;
63 
64 	return (uintptr_t)cookie >> 2;
65 }
66 
67 #define	XA_FLAGS_ALLOC	0
68 
69 #define	xa_alloc	linux_xa_alloc
70 #define	xa_destroy	linux_xa_destroy
71 #define	xa_erase	linux_xa_erase
72 #define	xa_find		linux_xa_find
73 #define	xa_find_after	linux_xa_find_after
74 #define	xa_init_flags	linux_xa_init_flags
75 #define	xa_limit_32b	linux_xa_limit_32b
76 #define	xa_load		linux_xa_load
77 #define	xa_store	linux_xa_store
78 
79 void	xa_init_flags(struct xarray *, gfp_t);
80 void	xa_destroy(struct xarray *);
81 
82 void *	xa_load(struct xarray *, unsigned long);
83 void *	xa_store(struct xarray *, unsigned long, void *, gfp_t);
84 void *	xa_erase(struct xarray *, unsigned long);
85 
86 int	xa_alloc(struct xarray *, uint32_t *, void *, struct xa_limit, gfp_t);
87 void *	xa_find(struct xarray *, unsigned long *, unsigned long, unsigned);
88 void *	xa_find_after(struct xarray *, unsigned long *, unsigned long,
89 	    unsigned);
90 
91 extern const struct xa_limit xa_limit_32b;
92 
93 #endif	/* _LINUX_XARRAY_H_ */
94