1/* SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause */
2/*
3 * Copyright (c) Yann Collet, Facebook, Inc.
4 * All rights reserved.
5 *
6 * This source code is licensed under both the BSD-style license (found in the
7 * LICENSE file in the root directory of this source tree) and the GPLv2 (found
8 * in the COPYING file in the root directory of this source tree).
9 * You may select, at your option, one of the above-listed licenses.
10 */
11
12#ifndef MEM_H_MODULE
13#define MEM_H_MODULE
14
15/*-****************************************
16*  Dependencies
17******************************************/
18#include <asm/unaligned.h>  /* get_unaligned, put_unaligned* */
19#include <linux/compiler.h>  /* inline */
20#include <linux/swab.h>  /* swab32, swab64 */
21#include <linux/types.h>  /* size_t, ptrdiff_t */
22#include "debug.h"  /* DEBUG_STATIC_ASSERT */
23
24/*-****************************************
25*  Compiler specifics
26******************************************/
27#define MEM_STATIC static inline
28
29/*-**************************************************************
30*  Basic Types
31*****************************************************************/
32typedef uint8_t  BYTE;
33typedef uint8_t  U8;
34typedef int8_t   S8;
35typedef uint16_t U16;
36typedef int16_t  S16;
37typedef uint32_t U32;
38typedef int32_t  S32;
39typedef uint64_t U64;
40typedef int64_t  S64;
41
42/*-**************************************************************
43*  Memory I/O API
44*****************************************************************/
45/*=== Static platform detection ===*/
46MEM_STATIC unsigned MEM_32bits(void);
47MEM_STATIC unsigned MEM_64bits(void);
48MEM_STATIC unsigned MEM_isLittleEndian(void);
49
50/*=== Native unaligned read/write ===*/
51MEM_STATIC U16 MEM_read16(const void* memPtr);
52MEM_STATIC U32 MEM_read32(const void* memPtr);
53MEM_STATIC U64 MEM_read64(const void* memPtr);
54MEM_STATIC size_t MEM_readST(const void* memPtr);
55
56MEM_STATIC void MEM_write16(void* memPtr, U16 value);
57MEM_STATIC void MEM_write32(void* memPtr, U32 value);
58MEM_STATIC void MEM_write64(void* memPtr, U64 value);
59
60/*=== Little endian unaligned read/write ===*/
61MEM_STATIC U16 MEM_readLE16(const void* memPtr);
62MEM_STATIC U32 MEM_readLE24(const void* memPtr);
63MEM_STATIC U32 MEM_readLE32(const void* memPtr);
64MEM_STATIC U64 MEM_readLE64(const void* memPtr);
65MEM_STATIC size_t MEM_readLEST(const void* memPtr);
66
67MEM_STATIC void MEM_writeLE16(void* memPtr, U16 val);
68MEM_STATIC void MEM_writeLE24(void* memPtr, U32 val);
69MEM_STATIC void MEM_writeLE32(void* memPtr, U32 val32);
70MEM_STATIC void MEM_writeLE64(void* memPtr, U64 val64);
71MEM_STATIC void MEM_writeLEST(void* memPtr, size_t val);
72
73/*=== Big endian unaligned read/write ===*/
74MEM_STATIC U32 MEM_readBE32(const void* memPtr);
75MEM_STATIC U64 MEM_readBE64(const void* memPtr);
76MEM_STATIC size_t MEM_readBEST(const void* memPtr);
77
78MEM_STATIC void MEM_writeBE32(void* memPtr, U32 val32);
79MEM_STATIC void MEM_writeBE64(void* memPtr, U64 val64);
80MEM_STATIC void MEM_writeBEST(void* memPtr, size_t val);
81
82/*=== Byteswap ===*/
83MEM_STATIC U32 MEM_swap32(U32 in);
84MEM_STATIC U64 MEM_swap64(U64 in);
85MEM_STATIC size_t MEM_swapST(size_t in);
86
87/*-**************************************************************
88*  Memory I/O Implementation
89*****************************************************************/
90MEM_STATIC unsigned MEM_32bits(void)
91{
92    return sizeof(size_t) == 4;
93}
94
95MEM_STATIC unsigned MEM_64bits(void)
96{
97    return sizeof(size_t) == 8;
98}
99
100#if defined(__LITTLE_ENDIAN)
101#define MEM_LITTLE_ENDIAN 1
102#else
103#define MEM_LITTLE_ENDIAN 0
104#endif
105
106MEM_STATIC unsigned MEM_isLittleEndian(void)
107{
108    return MEM_LITTLE_ENDIAN;
109}
110
111MEM_STATIC U16 MEM_read16(const void *memPtr)
112{
113    return get_unaligned((const U16 *)memPtr);
114}
115
116MEM_STATIC U32 MEM_read32(const void *memPtr)
117{
118    return get_unaligned((const U32 *)memPtr);
119}
120
121MEM_STATIC U64 MEM_read64(const void *memPtr)
122{
123    return get_unaligned((const U64 *)memPtr);
124}
125
126MEM_STATIC size_t MEM_readST(const void *memPtr)
127{
128    return get_unaligned((const size_t *)memPtr);
129}
130
131MEM_STATIC void MEM_write16(void *memPtr, U16 value)
132{
133    put_unaligned(value, (U16 *)memPtr);
134}
135
136MEM_STATIC void MEM_write32(void *memPtr, U32 value)
137{
138    put_unaligned(value, (U32 *)memPtr);
139}
140
141MEM_STATIC void MEM_write64(void *memPtr, U64 value)
142{
143    put_unaligned(value, (U64 *)memPtr);
144}
145
146/*=== Little endian r/w ===*/
147
148MEM_STATIC U16 MEM_readLE16(const void *memPtr)
149{
150    return get_unaligned_le16(memPtr);
151}
152
153MEM_STATIC void MEM_writeLE16(void *memPtr, U16 val)
154{
155    put_unaligned_le16(val, memPtr);
156}
157
158MEM_STATIC U32 MEM_readLE24(const void *memPtr)
159{
160    return MEM_readLE16(memPtr) + (((const BYTE *)memPtr)[2] << 16);
161}
162
163MEM_STATIC void MEM_writeLE24(void *memPtr, U32 val)
164{
165	MEM_writeLE16(memPtr, (U16)val);
166	((BYTE *)memPtr)[2] = (BYTE)(val >> 16);
167}
168
169MEM_STATIC U32 MEM_readLE32(const void *memPtr)
170{
171    return get_unaligned_le32(memPtr);
172}
173
174MEM_STATIC void MEM_writeLE32(void *memPtr, U32 val32)
175{
176    put_unaligned_le32(val32, memPtr);
177}
178
179MEM_STATIC U64 MEM_readLE64(const void *memPtr)
180{
181    return get_unaligned_le64(memPtr);
182}
183
184MEM_STATIC void MEM_writeLE64(void *memPtr, U64 val64)
185{
186    put_unaligned_le64(val64, memPtr);
187}
188
189MEM_STATIC size_t MEM_readLEST(const void *memPtr)
190{
191	if (MEM_32bits())
192		return (size_t)MEM_readLE32(memPtr);
193	else
194		return (size_t)MEM_readLE64(memPtr);
195}
196
197MEM_STATIC void MEM_writeLEST(void *memPtr, size_t val)
198{
199	if (MEM_32bits())
200		MEM_writeLE32(memPtr, (U32)val);
201	else
202		MEM_writeLE64(memPtr, (U64)val);
203}
204
205/*=== Big endian r/w ===*/
206
207MEM_STATIC U32 MEM_readBE32(const void *memPtr)
208{
209    return get_unaligned_be32(memPtr);
210}
211
212MEM_STATIC void MEM_writeBE32(void *memPtr, U32 val32)
213{
214    put_unaligned_be32(val32, memPtr);
215}
216
217MEM_STATIC U64 MEM_readBE64(const void *memPtr)
218{
219    return get_unaligned_be64(memPtr);
220}
221
222MEM_STATIC void MEM_writeBE64(void *memPtr, U64 val64)
223{
224    put_unaligned_be64(val64, memPtr);
225}
226
227MEM_STATIC size_t MEM_readBEST(const void *memPtr)
228{
229	if (MEM_32bits())
230		return (size_t)MEM_readBE32(memPtr);
231	else
232		return (size_t)MEM_readBE64(memPtr);
233}
234
235MEM_STATIC void MEM_writeBEST(void *memPtr, size_t val)
236{
237	if (MEM_32bits())
238		MEM_writeBE32(memPtr, (U32)val);
239	else
240		MEM_writeBE64(memPtr, (U64)val);
241}
242
243MEM_STATIC U32 MEM_swap32(U32 in)
244{
245    return swab32(in);
246}
247
248MEM_STATIC U64 MEM_swap64(U64 in)
249{
250    return swab64(in);
251}
252
253MEM_STATIC size_t MEM_swapST(size_t in)
254{
255    if (MEM_32bits())
256        return (size_t)MEM_swap32((U32)in);
257    else
258        return (size_t)MEM_swap64((U64)in);
259}
260
261#endif /* MEM_H_MODULE */
262