xref: /freebsd/sys/contrib/openzfs/include/zfs_fletcher.h (revision 02e9120893770924227138ba49df1edb3896112a)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or https://opensource.org/licenses/CDDL-1.0.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 /*
26  * Copyright 2013 Saso Kiselkov. All rights reserved.
27  */
28 
29 #ifndef	_ZFS_FLETCHER_H
30 #define	_ZFS_FLETCHER_H extern __attribute__((visibility("default")))
31 
32 #include <sys/types.h>
33 #include <sys/spa_checksum.h>
34 
35 #ifdef	__cplusplus
36 extern "C" {
37 #endif
38 
39 /*
40  * fletcher checksum functions
41  *
42  * Note: Fletcher checksum methods expect buffer size to be 4B aligned. This
43  * limitation stems from the algorithm design. Performing incremental checksum
44  * without said alignment would yield different results. Therefore, the code
45  * includes assertions for the size alignment.
46  * For compatibility, it is required that some code paths calculate checksum of
47  * non-aligned buffer sizes. For this purpose, `fletcher_4_native_varsize()`
48  * checksum method is added. This method will ignore last (size % 4) bytes of
49  * the data buffer.
50  */
51 _ZFS_FLETCHER_H void fletcher_init(zio_cksum_t *);
52 _ZFS_FLETCHER_H void fletcher_2_native(const void *, uint64_t, const void *,
53     zio_cksum_t *);
54 _ZFS_FLETCHER_H void fletcher_2_byteswap(const void *, uint64_t, const void *,
55     zio_cksum_t *);
56 _ZFS_FLETCHER_H void fletcher_4_native(const void *, uint64_t, const void *,
57     zio_cksum_t *);
58 _ZFS_FLETCHER_H int fletcher_2_incremental_native(void *, size_t, void *);
59 _ZFS_FLETCHER_H int fletcher_2_incremental_byteswap(void *, size_t, void *);
60 _ZFS_FLETCHER_H void fletcher_4_native_varsize(const void *, uint64_t,
61     zio_cksum_t *);
62 _ZFS_FLETCHER_H void fletcher_4_byteswap(const void *, uint64_t, const void *,
63     zio_cksum_t *);
64 _ZFS_FLETCHER_H int fletcher_4_incremental_native(void *, size_t, void *);
65 _ZFS_FLETCHER_H int fletcher_4_incremental_byteswap(void *, size_t, void *);
66 _ZFS_FLETCHER_H int fletcher_4_impl_set(const char *selector);
67 _ZFS_FLETCHER_H void fletcher_4_init(void);
68 _ZFS_FLETCHER_H void fletcher_4_fini(void);
69 
70 
71 
72 /* Internal fletcher ctx */
73 
74 typedef struct zfs_fletcher_superscalar {
75 	uint64_t v[4];
76 } zfs_fletcher_superscalar_t;
77 
78 typedef struct zfs_fletcher_sse {
79 	uint64_t v[2];
80 } zfs_fletcher_sse_t;
81 
82 typedef struct zfs_fletcher_avx {
83 	uint64_t v[4];
84 } zfs_fletcher_avx_t;
85 
86 typedef struct zfs_fletcher_avx512 {
87 	uint64_t v[8];
88 } zfs_fletcher_avx512_t;
89 
90 typedef struct zfs_fletcher_aarch64_neon {
91 	uint64_t v[2];
92 } zfs_fletcher_aarch64_neon_t;
93 
94 
95 typedef union fletcher_4_ctx {
96 	zio_cksum_t scalar;
97 	zfs_fletcher_superscalar_t superscalar[4];
98 
99 #if defined(HAVE_SSE2) || (defined(HAVE_SSE2) && defined(HAVE_SSSE3))
100 	zfs_fletcher_sse_t sse[4];
101 #endif
102 #if defined(HAVE_AVX) && defined(HAVE_AVX2)
103 	zfs_fletcher_avx_t avx[4];
104 #endif
105 #if defined(__x86_64) && defined(HAVE_AVX512F)
106 	zfs_fletcher_avx512_t avx512[4];
107 #endif
108 #if defined(__aarch64__)
109 	zfs_fletcher_aarch64_neon_t aarch64_neon[4];
110 #endif
111 } fletcher_4_ctx_t;
112 
113 /*
114  * fletcher checksum struct
115  */
116 typedef void (*fletcher_4_init_f)(fletcher_4_ctx_t *);
117 typedef void (*fletcher_4_fini_f)(fletcher_4_ctx_t *, zio_cksum_t *);
118 typedef void (*fletcher_4_compute_f)(fletcher_4_ctx_t *,
119     const void *, uint64_t);
120 
121 typedef struct fletcher_4_func {
122 	fletcher_4_init_f init_native;
123 	fletcher_4_fini_f fini_native;
124 	fletcher_4_compute_f compute_native;
125 	fletcher_4_init_f init_byteswap;
126 	fletcher_4_fini_f fini_byteswap;
127 	fletcher_4_compute_f compute_byteswap;
128 	boolean_t (*valid)(void);
129 	boolean_t uses_fpu;
130 	const char *name;
131 } __attribute__((aligned(64))) fletcher_4_ops_t;
132 
133 _ZFS_FLETCHER_H const fletcher_4_ops_t fletcher_4_superscalar_ops;
134 _ZFS_FLETCHER_H const fletcher_4_ops_t fletcher_4_superscalar4_ops;
135 
136 #if defined(HAVE_SSE2)
137 _ZFS_FLETCHER_H const fletcher_4_ops_t fletcher_4_sse2_ops;
138 #endif
139 
140 #if defined(HAVE_SSE2) && defined(HAVE_SSSE3)
141 _ZFS_FLETCHER_H const fletcher_4_ops_t fletcher_4_ssse3_ops;
142 #endif
143 
144 #if defined(HAVE_AVX) && defined(HAVE_AVX2)
145 _ZFS_FLETCHER_H const fletcher_4_ops_t fletcher_4_avx2_ops;
146 #endif
147 
148 #if defined(__x86_64) && defined(HAVE_AVX512F)
149 _ZFS_FLETCHER_H const fletcher_4_ops_t fletcher_4_avx512f_ops;
150 #endif
151 
152 #if defined(__x86_64) && defined(HAVE_AVX512BW)
153 _ZFS_FLETCHER_H const fletcher_4_ops_t fletcher_4_avx512bw_ops;
154 #endif
155 
156 #if defined(__aarch64__)
157 _ZFS_FLETCHER_H const fletcher_4_ops_t fletcher_4_aarch64_neon_ops;
158 #endif
159 
160 #ifdef	__cplusplus
161 }
162 #endif
163 
164 #endif	/* _ZFS_FLETCHER_H */
165