xref: /freebsd/sys/contrib/openzfs/include/zfs_fletcher.h (revision dd41de95a84d979615a2ef11df6850622bf6184e)
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 http://www.opensolaris.org/os/licensing.
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
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 void fletcher_init(zio_cksum_t *);
52 void fletcher_2_native(const void *, uint64_t, const void *, zio_cksum_t *);
53 void fletcher_2_byteswap(const void *, uint64_t, const void *, zio_cksum_t *);
54 void fletcher_4_native(const void *, uint64_t, const void *, zio_cksum_t *);
55 int fletcher_2_incremental_native(void *, size_t, void *);
56 int fletcher_2_incremental_byteswap(void *, size_t, void *);
57 void fletcher_4_native_varsize(const void *, uint64_t, zio_cksum_t *);
58 void fletcher_4_byteswap(const void *, uint64_t, const void *, zio_cksum_t *);
59 int fletcher_4_incremental_native(void *, size_t, void *);
60 int fletcher_4_incremental_byteswap(void *, size_t, void *);
61 int fletcher_4_impl_set(const char *selector);
62 void fletcher_4_init(void);
63 void fletcher_4_fini(void);
64 
65 
66 
67 /* Internal fletcher ctx */
68 
69 typedef struct zfs_fletcher_superscalar {
70 	uint64_t v[4];
71 } zfs_fletcher_superscalar_t;
72 
73 typedef struct zfs_fletcher_sse {
74 	uint64_t v[2] __attribute__((aligned(16)));
75 } zfs_fletcher_sse_t;
76 
77 typedef struct zfs_fletcher_avx {
78 	uint64_t v[4] __attribute__((aligned(32)));
79 } zfs_fletcher_avx_t;
80 
81 typedef struct zfs_fletcher_avx512 {
82 	uint64_t v[8] __attribute__((aligned(64)));
83 } zfs_fletcher_avx512_t;
84 
85 typedef struct zfs_fletcher_aarch64_neon {
86 	uint64_t v[2] __attribute__((aligned(16)));
87 } zfs_fletcher_aarch64_neon_t;
88 
89 
90 typedef union fletcher_4_ctx {
91 	zio_cksum_t scalar;
92 	zfs_fletcher_superscalar_t superscalar[4];
93 
94 #if defined(HAVE_SSE2) || (defined(HAVE_SSE2) && defined(HAVE_SSSE3))
95 	zfs_fletcher_sse_t sse[4];
96 #endif
97 #if defined(HAVE_AVX) && defined(HAVE_AVX2)
98 	zfs_fletcher_avx_t avx[4];
99 #endif
100 #if defined(__x86_64) && defined(HAVE_AVX512F)
101 	zfs_fletcher_avx512_t avx512[4];
102 #endif
103 #if defined(__aarch64__)
104 	zfs_fletcher_aarch64_neon_t aarch64_neon[4];
105 #endif
106 } fletcher_4_ctx_t;
107 
108 /*
109  * fletcher checksum struct
110  */
111 typedef void (*fletcher_4_init_f)(fletcher_4_ctx_t *);
112 typedef void (*fletcher_4_fini_f)(fletcher_4_ctx_t *, zio_cksum_t *);
113 typedef void (*fletcher_4_compute_f)(fletcher_4_ctx_t *,
114     const void *, uint64_t);
115 
116 typedef struct fletcher_4_func {
117 	fletcher_4_init_f init_native;
118 	fletcher_4_fini_f fini_native;
119 	fletcher_4_compute_f compute_native;
120 	fletcher_4_init_f init_byteswap;
121 	fletcher_4_fini_f fini_byteswap;
122 	fletcher_4_compute_f compute_byteswap;
123 	boolean_t (*valid)(void);
124 	const char *name;
125 } fletcher_4_ops_t;
126 
127 extern const fletcher_4_ops_t fletcher_4_superscalar_ops;
128 extern const fletcher_4_ops_t fletcher_4_superscalar4_ops;
129 
130 #if defined(HAVE_SSE2)
131 extern const fletcher_4_ops_t fletcher_4_sse2_ops;
132 #endif
133 
134 #if defined(HAVE_SSE2) && defined(HAVE_SSSE3)
135 extern const fletcher_4_ops_t fletcher_4_ssse3_ops;
136 #endif
137 
138 #if defined(HAVE_AVX) && defined(HAVE_AVX2)
139 extern const fletcher_4_ops_t fletcher_4_avx2_ops;
140 #endif
141 
142 #if defined(__x86_64) && defined(HAVE_AVX512F)
143 extern const fletcher_4_ops_t fletcher_4_avx512f_ops;
144 #endif
145 
146 #if defined(__x86_64) && defined(HAVE_AVX512BW)
147 extern const fletcher_4_ops_t fletcher_4_avx512bw_ops;
148 #endif
149 
150 #if defined(__aarch64__)
151 extern const fletcher_4_ops_t fletcher_4_aarch64_neon_ops;
152 #endif
153 
154 #ifdef	__cplusplus
155 }
156 #endif
157 
158 #endif	/* _ZFS_FLETCHER_H */
159