1/*
2 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17 */
18#ifndef __XFS_ARCH_H__
19#define __XFS_ARCH_H__
20
21#ifndef XFS_BIG_INUMS
22# error XFS_BIG_INUMS must be defined true or false
23#endif
24
25#ifdef __KERNEL__
26
27#include <asm/byteorder.h>
28
29#ifdef __BIG_ENDIAN
30#define	XFS_NATIVE_HOST	1
31#else
32#undef XFS_NATIVE_HOST
33#endif
34
35#else /* __KERNEL__ */
36
37#if __BYTE_ORDER == __BIG_ENDIAN
38#define	XFS_NATIVE_HOST	1
39#else
40#undef XFS_NATIVE_HOST
41#endif
42
43#ifdef XFS_NATIVE_HOST
44#define cpu_to_be16(val)	((__be16)(val))
45#define cpu_to_be32(val)	((__be32)(val))
46#define cpu_to_be64(val)	((__be64)(val))
47#define be16_to_cpu(val)	((__uint16_t)(val))
48#define be32_to_cpu(val)	((__uint32_t)(val))
49#define be64_to_cpu(val)	((__uint64_t)(val))
50#else
51#define cpu_to_be16(val)	(__swab16((__uint16_t)(val)))
52#define cpu_to_be32(val)	(__swab32((__uint32_t)(val)))
53#define cpu_to_be64(val)	(__swab64((__uint64_t)(val)))
54#define be16_to_cpu(val)	(__swab16((__be16)(val)))
55#define be32_to_cpu(val)	(__swab32((__be32)(val)))
56#define be64_to_cpu(val)	(__swab64((__be64)(val)))
57#endif
58
59#endif	/* __KERNEL__ */
60
61/* do we need conversion? */
62#define ARCH_NOCONVERT 1
63#ifdef XFS_NATIVE_HOST
64# define ARCH_CONVERT	ARCH_NOCONVERT
65#else
66# define ARCH_CONVERT	0
67#endif
68
69/* generic swapping macros */
70
71#ifndef HAVE_SWABMACROS
72#define INT_SWAP16(type,var) ((typeof(type))(__swab16((__u16)(var))))
73#define INT_SWAP32(type,var) ((typeof(type))(__swab32((__u32)(var))))
74#define INT_SWAP64(type,var) ((typeof(type))(__swab64((__u64)(var))))
75#endif
76
77#define INT_SWAP(type, var) \
78    ((sizeof(type) == 8) ? INT_SWAP64(type,var) : \
79    ((sizeof(type) == 4) ? INT_SWAP32(type,var) : \
80    ((sizeof(type) == 2) ? INT_SWAP16(type,var) : \
81    (var))))
82
83/*
84 * get and set integers from potentially unaligned locations
85 */
86
87#define INT_GET_UNALIGNED_16_BE(pointer) \
88   ((__u16)((((__u8*)(pointer))[0] << 8) | (((__u8*)(pointer))[1])))
89#define INT_SET_UNALIGNED_16_BE(pointer,value) \
90    { \
91	((__u8*)(pointer))[0] = (((value) >> 8) & 0xff); \
92	((__u8*)(pointer))[1] = (((value)     ) & 0xff); \
93    }
94
95/* define generic INT_ macros */
96
97#define INT_GET(reference,arch) \
98    (((arch) == ARCH_NOCONVERT) \
99	? \
100	    (reference) \
101	: \
102	    INT_SWAP((reference),(reference)) \
103    )
104
105/* does not return a value */
106#define INT_SET(reference,arch,valueref) \
107    (__builtin_constant_p(valueref) ? \
108	(void)( (reference) = ( ((arch) != ARCH_NOCONVERT) ? (INT_SWAP((reference),(valueref))) : (valueref)) ) : \
109	(void)( \
110	    ((reference) = (valueref)), \
111	    ( ((arch) != ARCH_NOCONVERT) ? (reference) = INT_SWAP((reference),(reference)) : 0 ) \
112	) \
113    )
114
115/* does not return a value */
116#define INT_MOD_EXPR(reference,arch,code) \
117    (((arch) == ARCH_NOCONVERT) \
118	? \
119	    (void)((reference) code) \
120	: \
121	    (void)( \
122		(reference) = INT_GET((reference),arch) , \
123		((reference) code), \
124		INT_SET(reference, arch, reference) \
125	    ) \
126    )
127
128/* does not return a value */
129#define INT_MOD(reference,arch,delta) \
130    (void)( \
131	INT_MOD_EXPR(reference,arch,+=(delta)) \
132    )
133
134/*
135 * INT_COPY - copy a value between two locations with the
136 *	      _same architecture_ but _potentially different sizes_
137 *
138 *	    if the types of the two parameters are equal or they are
139 *		in native architecture, a simple copy is done
140 *
141 *	    otherwise, architecture conversions are done
142 *
143 */
144
145/* does not return a value */
146#define INT_COPY(dst,src,arch) \
147    ( \
148	((sizeof(dst) == sizeof(src)) || ((arch) == ARCH_NOCONVERT)) \
149	    ? \
150		(void)((dst) = (src)) \
151	    : \
152		INT_SET(dst, arch, INT_GET(src, arch)) \
153    )
154
155/*
156 * INT_XLATE - copy a value in either direction between two locations
157 *	       with different architectures
158 *
159 *		    dir < 0	- copy from memory to buffer (native to arch)
160 *		    dir > 0	- copy from buffer to memory (arch to native)
161 */
162
163/* does not return a value */
164#define INT_XLATE(buf,mem,dir,arch) {\
165    ASSERT(dir); \
166    if (dir>0) { \
167	(mem)=INT_GET(buf, arch); \
168    } else { \
169	INT_SET(buf, arch, mem); \
170    } \
171}
172
173static inline void be16_add(__be16 *a, __s16 b)
174{
175	*a = cpu_to_be16(be16_to_cpu(*a) + b);
176}
177
178static inline void be32_add(__be32 *a, __s32 b)
179{
180	*a = cpu_to_be32(be32_to_cpu(*a) + b);
181}
182
183static inline void be64_add(__be64 *a, __s64 b)
184{
185	*a = cpu_to_be64(be64_to_cpu(*a) + b);
186}
187
188/*
189 * In directories inode numbers are stored as unaligned arrays of unsigned
190 * 8bit integers on disk.
191 *
192 * For v1 directories or v2 directories that contain inode numbers that
193 * do not fit into 32bit the array has eight members, but the first member
194 * is always zero:
195 *
196 *  |unused|48-55|40-47|32-39|24-31|16-23| 8-15| 0- 7|
197 *
198 * For v2 directories that only contain entries with inode numbers that fit
199 * into 32bits a four-member array is used:
200 *
201 *  |24-31|16-23| 8-15| 0- 7|
202 */
203
204#define XFS_GET_DIR_INO4(di) \
205	(((__u32)(di).i[0] << 24) | ((di).i[1] << 16) | ((di).i[2] << 8) | ((di).i[3]))
206
207#define XFS_PUT_DIR_INO4(from, di) \
208do { \
209	(di).i[0] = (((from) & 0xff000000ULL) >> 24); \
210	(di).i[1] = (((from) & 0x00ff0000ULL) >> 16); \
211	(di).i[2] = (((from) & 0x0000ff00ULL) >> 8); \
212	(di).i[3] = ((from) & 0x000000ffULL); \
213} while (0)
214
215#define XFS_DI_HI(di) \
216	(((__u32)(di).i[1] << 16) | ((di).i[2] << 8) | ((di).i[3]))
217#define XFS_DI_LO(di) \
218	(((__u32)(di).i[4] << 24) | ((di).i[5] << 16) | ((di).i[6] << 8) | ((di).i[7]))
219
220#define XFS_GET_DIR_INO8(di)        \
221	(((xfs_ino_t)XFS_DI_LO(di) & 0xffffffffULL) | \
222	 ((xfs_ino_t)XFS_DI_HI(di) << 32))
223
224#define XFS_PUT_DIR_INO8(from, di) \
225do { \
226	(di).i[0] = 0; \
227	(di).i[1] = (((from) & 0x00ff000000000000ULL) >> 48); \
228	(di).i[2] = (((from) & 0x0000ff0000000000ULL) >> 40); \
229	(di).i[3] = (((from) & 0x000000ff00000000ULL) >> 32); \
230	(di).i[4] = (((from) & 0x00000000ff000000ULL) >> 24); \
231	(di).i[5] = (((from) & 0x0000000000ff0000ULL) >> 16); \
232	(di).i[6] = (((from) & 0x000000000000ff00ULL) >> 8); \
233	(di).i[7] = ((from) & 0x00000000000000ffULL); \
234} while (0)
235
236#endif	/* __XFS_ARCH_H__ */
237