1/* SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause */
2/*
3 * Copyright (c) Meta Platforms, Inc. and affiliates.
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 <linux/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#undef MEM_STATIC /* may be already defined from common/compiler.h */
28#define MEM_STATIC static inline
29
30/*-**************************************************************
31* Basic Types
32*****************************************************************/
33typedef uint8_t BYTE;
34typedef uint8_t U8;
35typedef int8_t S8;
36typedef uint16_t U16;
37typedef int16_t S16;
38typedef uint32_t U32;
39typedef int32_t S32;
40typedef uint64_t U64;
41typedef int64_t S64;
42
43/*-**************************************************************
44* Memory I/O API
45*****************************************************************/
46/*=== Static platform detection ===*/
47MEM_STATIC unsigned MEM_32bits(void);
48MEM_STATIC unsigned MEM_64bits(void);
49MEM_STATIC unsigned MEM_isLittleEndian(void);
50
51/*=== Native unaligned read/write ===*/
52MEM_STATIC U16 MEM_read16(const void* memPtr);
53MEM_STATIC U32 MEM_read32(const void* memPtr);
54MEM_STATIC U64 MEM_read64(const void* memPtr);
55MEM_STATIC size_t MEM_readST(const void* memPtr);
56
57MEM_STATIC void MEM_write16(void* memPtr, U16 value);
58MEM_STATIC void MEM_write32(void* memPtr, U32 value);
59MEM_STATIC void MEM_write64(void* memPtr, U64 value);
60
61/*=== Little endian unaligned read/write ===*/
62MEM_STATIC U16 MEM_readLE16(const void* memPtr);
63MEM_STATIC U32 MEM_readLE24(const void* memPtr);
64MEM_STATIC U32 MEM_readLE32(const void* memPtr);
65MEM_STATIC U64 MEM_readLE64(const void* memPtr);
66MEM_STATIC size_t MEM_readLEST(const void* memPtr);
67
68MEM_STATIC void MEM_writeLE16(void* memPtr, U16 val);
69MEM_STATIC void MEM_writeLE24(void* memPtr, U32 val);
70MEM_STATIC void MEM_writeLE32(void* memPtr, U32 val32);
71MEM_STATIC void MEM_writeLE64(void* memPtr, U64 val64);
72MEM_STATIC void MEM_writeLEST(void* memPtr, size_t val);
73
74/*=== Big endian unaligned read/write ===*/
75MEM_STATIC U32 MEM_readBE32(const void* memPtr);
76MEM_STATIC U64 MEM_readBE64(const void* memPtr);
77MEM_STATIC size_t MEM_readBEST(const void* memPtr);
78
79MEM_STATIC void MEM_writeBE32(void* memPtr, U32 val32);
80MEM_STATIC void MEM_writeBE64(void* memPtr, U64 val64);
81MEM_STATIC void MEM_writeBEST(void* memPtr, size_t val);
82
83/*=== Byteswap ===*/
84MEM_STATIC U32 MEM_swap32(U32 in);
85MEM_STATIC U64 MEM_swap64(U64 in);
86MEM_STATIC size_t MEM_swapST(size_t in);
87
88/*-**************************************************************
89* Memory I/O Implementation
90*****************************************************************/
91MEM_STATIC unsigned MEM_32bits(void)
92{
93 return sizeof(size_t) == 4;
94}
95
96MEM_STATIC unsigned MEM_64bits(void)
97{
98 return sizeof(size_t) == 8;
99}
100
101#if defined(__LITTLE_ENDIAN)
102#define MEM_LITTLE_ENDIAN 1
103#else
104#define MEM_LITTLE_ENDIAN 0
105#endif
106
107MEM_STATIC unsigned MEM_isLittleEndian(void)
108{
109 return MEM_LITTLE_ENDIAN;
110}
111
112MEM_STATIC U16 MEM_read16(const void *memPtr)
113{
114 return get_unaligned((const U16 *)memPtr);
115}
116
117MEM_STATIC U32 MEM_read32(const void *memPtr)
118{
119 return get_unaligned((const U32 *)memPtr);
120}
121
122MEM_STATIC U64 MEM_read64(const void *memPtr)
123{
124 return get_unaligned((const U64 *)memPtr);
125}
126
127MEM_STATIC size_t MEM_readST(const void *memPtr)
128{
129 return get_unaligned((const size_t *)memPtr);
130}
131
132MEM_STATIC void MEM_write16(void *memPtr, U16 value)
133{
134 put_unaligned(value, (U16 *)memPtr);
135}
136
137MEM_STATIC void MEM_write32(void *memPtr, U32 value)
138{
139 put_unaligned(value, (U32 *)memPtr);
140}
141
142MEM_STATIC void MEM_write64(void *memPtr, U64 value)
143{
144 put_unaligned(value, (U64 *)memPtr);
145}
146
147/*=== Little endian r/w ===*/
148
149MEM_STATIC U16 MEM_readLE16(const void *memPtr)
150{
151 return get_unaligned_le16(p: memPtr);
152}
153
154MEM_STATIC void MEM_writeLE16(void *memPtr, U16 val)
155{
156 put_unaligned_le16(val, p: memPtr);
157}
158
159MEM_STATIC U32 MEM_readLE24(const void *memPtr)
160{
161 return MEM_readLE16(memPtr) + (((const BYTE *)memPtr)[2] << 16);
162}
163
164MEM_STATIC void MEM_writeLE24(void *memPtr, U32 val)
165{
166 MEM_writeLE16(memPtr, val: (U16)val);
167 ((BYTE *)memPtr)[2] = (BYTE)(val >> 16);
168}
169
170MEM_STATIC U32 MEM_readLE32(const void *memPtr)
171{
172 return get_unaligned_le32(p: memPtr);
173}
174
175MEM_STATIC void MEM_writeLE32(void *memPtr, U32 val32)
176{
177 put_unaligned_le32(val: val32, p: memPtr);
178}
179
180MEM_STATIC U64 MEM_readLE64(const void *memPtr)
181{
182 return get_unaligned_le64(p: memPtr);
183}
184
185MEM_STATIC void MEM_writeLE64(void *memPtr, U64 val64)
186{
187 put_unaligned_le64(val: val64, p: memPtr);
188}
189
190MEM_STATIC size_t MEM_readLEST(const void *memPtr)
191{
192 if (MEM_32bits())
193 return (size_t)MEM_readLE32(memPtr);
194 else
195 return (size_t)MEM_readLE64(memPtr);
196}
197
198MEM_STATIC void MEM_writeLEST(void *memPtr, size_t val)
199{
200 if (MEM_32bits())
201 MEM_writeLE32(memPtr, val32: (U32)val);
202 else
203 MEM_writeLE64(memPtr, val64: (U64)val);
204}
205
206/*=== Big endian r/w ===*/
207
208MEM_STATIC U32 MEM_readBE32(const void *memPtr)
209{
210 return get_unaligned_be32(p: memPtr);
211}
212
213MEM_STATIC void MEM_writeBE32(void *memPtr, U32 val32)
214{
215 put_unaligned_be32(val: val32, p: memPtr);
216}
217
218MEM_STATIC U64 MEM_readBE64(const void *memPtr)
219{
220 return get_unaligned_be64(p: memPtr);
221}
222
223MEM_STATIC void MEM_writeBE64(void *memPtr, U64 val64)
224{
225 put_unaligned_be64(val: val64, p: memPtr);
226}
227
228MEM_STATIC size_t MEM_readBEST(const void *memPtr)
229{
230 if (MEM_32bits())
231 return (size_t)MEM_readBE32(memPtr);
232 else
233 return (size_t)MEM_readBE64(memPtr);
234}
235
236MEM_STATIC void MEM_writeBEST(void *memPtr, size_t val)
237{
238 if (MEM_32bits())
239 MEM_writeBE32(memPtr, val32: (U32)val);
240 else
241 MEM_writeBE64(memPtr, val64: (U64)val);
242}
243
244MEM_STATIC U32 MEM_swap32(U32 in)
245{
246 return swab32(in);
247}
248
249MEM_STATIC U64 MEM_swap64(U64 in)
250{
251 return swab64(in);
252}
253
254MEM_STATIC size_t MEM_swapST(size_t in)
255{
256 if (MEM_32bits())
257 return (size_t)MEM_swap32(in: (U32)in);
258 else
259 return (size_t)MEM_swap64(in: (U64)in);
260}
261
262#endif /* MEM_H_MODULE */
263