1 #ifndef __LZ4DEFS_H__
2 #define __LZ4DEFS_H__
3 
4 /*
5  * lz4defs.h -- common and architecture specific defines for the kernel usage
6 
7  * LZ4 - Fast LZ compression algorithm
8  * Copyright (C) 2011-2016, Yann Collet.
9  * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions are
12  * met:
13  *	* Redistributions of source code must retain the above copyright
14  *	  notice, this list of conditions and the following disclaimer.
15  *	* Redistributions in binary form must reproduce the above
16  * copyright notice, this list of conditions and the following disclaimer
17  * in the documentation and/or other materials provided with the
18  * distribution.
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  * You can contact the author at :
31  *	- LZ4 homepage : http://www.lz4.org
32  *	- LZ4 source repository : https://github.com/lz4/lz4
33  *
34  *	Changed for kernel usage by:
35  *	Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
36  */
37 
38 #include <asm/unaligned.h>
39 #include <linux/string.h>	 /* memset, memcpy */
40 
41 #define FORCE_INLINE __always_inline
42 
43 /*-************************************
44  *	Basic Types
45  **************************************/
46 #include <linux/types.h>
47 
48 typedef	uint8_t BYTE;
49 typedef uint16_t U16;
50 typedef uint32_t U32;
51 typedef	int32_t S32;
52 typedef uint64_t U64;
53 typedef uintptr_t uptrval;
54 
55 /*-************************************
56  *	Architecture specifics
57  **************************************/
58 #if defined(CONFIG_64BIT)
59 #define LZ4_ARCH64 1
60 #else
61 #define LZ4_ARCH64 0
62 #endif
63 
64 #if defined(__LITTLE_ENDIAN)
65 #define LZ4_LITTLE_ENDIAN 1
66 #else
67 #define LZ4_LITTLE_ENDIAN 0
68 #endif
69 
70 /*-************************************
71  *	Constants
72  **************************************/
73 #define MINMATCH 4
74 
75 #define WILDCOPYLENGTH 8
76 #define LASTLITERALS 5
77 #define MFLIMIT (WILDCOPYLENGTH + MINMATCH)
78 
79 /* Increase this value ==> compression run slower on incompressible data */
80 #define LZ4_SKIPTRIGGER 6
81 
82 #define HASH_UNIT sizeof(size_t)
83 
84 #define KB (1 << 10)
85 #define MB (1 << 20)
86 #define GB (1U << 30)
87 
88 #define MAXD_LOG 16
89 #define MAX_DISTANCE ((1 << MAXD_LOG) - 1)
90 #define STEPSIZE sizeof(size_t)
91 
92 #define ML_BITS	4
93 #define ML_MASK	((1U << ML_BITS) - 1)
94 #define RUN_BITS (8 - ML_BITS)
95 #define RUN_MASK ((1U << RUN_BITS) - 1)
96 
97 /*-************************************
98  *	Reading and writing into memory
99  **************************************/
LZ4_read16(const void * ptr)100 static FORCE_INLINE U16 LZ4_read16(const void *ptr)
101 {
102 	return get_unaligned((const U16 *)ptr);
103 }
104 
LZ4_read32(const void * ptr)105 static FORCE_INLINE U32 LZ4_read32(const void *ptr)
106 {
107 	return get_unaligned((const U32 *)ptr);
108 }
109 
LZ4_read_ARCH(const void * ptr)110 static FORCE_INLINE size_t LZ4_read_ARCH(const void *ptr)
111 {
112 	return get_unaligned((const size_t *)ptr);
113 }
114 
LZ4_write16(void * memPtr,U16 value)115 static FORCE_INLINE void LZ4_write16(void *memPtr, U16 value)
116 {
117 	put_unaligned(value, (U16 *)memPtr);
118 }
119 
LZ4_write32(void * memPtr,U32 value)120 static FORCE_INLINE void LZ4_write32(void *memPtr, U32 value)
121 {
122 	put_unaligned(value, (U32 *)memPtr);
123 }
124 
LZ4_readLE16(const void * memPtr)125 static FORCE_INLINE U16 LZ4_readLE16(const void *memPtr)
126 {
127 	return get_unaligned_le16(memPtr);
128 }
129 
LZ4_writeLE16(void * memPtr,U16 value)130 static FORCE_INLINE void LZ4_writeLE16(void *memPtr, U16 value)
131 {
132 	return put_unaligned_le16(value, memPtr);
133 }
134 
LZ4_copy8(void * dst,const void * src)135 static FORCE_INLINE void LZ4_copy8(void *dst, const void *src)
136 {
137 #if LZ4_ARCH64
138 	U64 a = get_unaligned((const U64 *)src);
139 
140 	put_unaligned(a, (U64 *)dst);
141 #else
142 	U32 a = get_unaligned((const U32 *)src);
143 	U32 b = get_unaligned((const U32 *)src + 1);
144 
145 	put_unaligned(a, (U32 *)dst);
146 	put_unaligned(b, (U32 *)dst + 1);
147 #endif
148 }
149 
150 /*
151  * customized variant of memcpy,
152  * which can overwrite up to 7 bytes beyond dstEnd
153  */
LZ4_wildCopy(void * dstPtr,const void * srcPtr,void * dstEnd)154 static FORCE_INLINE void LZ4_wildCopy(void *dstPtr,
155 	const void *srcPtr, void *dstEnd)
156 {
157 	BYTE *d = (BYTE *)dstPtr;
158 	const BYTE *s = (const BYTE *)srcPtr;
159 	BYTE *const e = (BYTE *)dstEnd;
160 
161 	do {
162 		LZ4_copy8(d, s);
163 		d += 8;
164 		s += 8;
165 	} while (d < e);
166 }
167 
LZ4_NbCommonBytes(register size_t val)168 static FORCE_INLINE unsigned int LZ4_NbCommonBytes(register size_t val)
169 {
170 #if LZ4_LITTLE_ENDIAN
171 	return __ffs(val) >> 3;
172 #else
173 	return (BITS_PER_LONG - 1 - __fls(val)) >> 3;
174 #endif
175 }
176 
LZ4_count(const BYTE * pIn,const BYTE * pMatch,const BYTE * pInLimit)177 static FORCE_INLINE unsigned int LZ4_count(
178 	const BYTE *pIn,
179 	const BYTE *pMatch,
180 	const BYTE *pInLimit)
181 {
182 	const BYTE *const pStart = pIn;
183 
184 	while (likely(pIn < pInLimit - (STEPSIZE - 1))) {
185 		size_t const diff = LZ4_read_ARCH(pMatch) ^ LZ4_read_ARCH(pIn);
186 
187 		if (!diff) {
188 			pIn += STEPSIZE;
189 			pMatch += STEPSIZE;
190 			continue;
191 		}
192 
193 		pIn += LZ4_NbCommonBytes(diff);
194 
195 		return (unsigned int)(pIn - pStart);
196 	}
197 
198 #if LZ4_ARCH64
199 	if ((pIn < (pInLimit - 3))
200 		&& (LZ4_read32(pMatch) == LZ4_read32(pIn))) {
201 		pIn += 4;
202 		pMatch += 4;
203 	}
204 #endif
205 
206 	if ((pIn < (pInLimit - 1))
207 		&& (LZ4_read16(pMatch) == LZ4_read16(pIn))) {
208 		pIn += 2;
209 		pMatch += 2;
210 	}
211 
212 	if ((pIn < pInLimit) && (*pMatch == *pIn))
213 		pIn++;
214 
215 	return (unsigned int)(pIn - pStart);
216 }
217 
218 typedef enum { noLimit = 0, limitedOutput = 1 } limitedOutput_directive;
219 typedef enum { byPtr, byU32, byU16 } tableType_t;
220 
221 typedef enum { noDict = 0, withPrefix64k, usingExtDict } dict_directive;
222 typedef enum { noDictIssue = 0, dictSmall } dictIssue_directive;
223 
224 typedef enum { endOnOutputSize = 0, endOnInputSize = 1 } endCondition_directive;
225 typedef enum { full = 0, partial = 1 } earlyEnd_directive;
226 
227 #endif
228