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Diffstat (limited to 'drivers/md/raid6int.uc')
-rw-r--r-- | drivers/md/raid6int.uc | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/drivers/md/raid6int.uc b/drivers/md/raid6int.uc new file mode 100644 index 000000000000..ad004cee0e26 --- /dev/null +++ b/drivers/md/raid6int.uc | |||
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1 | /* -*- linux-c -*- ------------------------------------------------------- * | ||
2 | * | ||
3 | * Copyright 2002-2004 H. Peter Anvin - All Rights Reserved | ||
4 | * | ||
5 | * This program is free software; you can redistribute it and/or modify | ||
6 | * it under the terms of the GNU General Public License as published by | ||
7 | * the Free Software Foundation, Inc., 53 Temple Place Ste 330, | ||
8 | * Bostom MA 02111-1307, USA; either version 2 of the License, or | ||
9 | * (at your option) any later version; incorporated herein by reference. | ||
10 | * | ||
11 | * ----------------------------------------------------------------------- */ | ||
12 | |||
13 | /* | ||
14 | * raid6int$#.c | ||
15 | * | ||
16 | * $#-way unrolled portable integer math RAID-6 instruction set | ||
17 | * | ||
18 | * This file is postprocessed using unroll.pl | ||
19 | */ | ||
20 | |||
21 | #include "raid6.h" | ||
22 | |||
23 | /* | ||
24 | * This is the C data type to use | ||
25 | */ | ||
26 | |||
27 | /* Change this from BITS_PER_LONG if there is something better... */ | ||
28 | #if BITS_PER_LONG == 64 | ||
29 | # define NBYTES(x) ((x) * 0x0101010101010101UL) | ||
30 | # define NSIZE 8 | ||
31 | # define NSHIFT 3 | ||
32 | # define NSTRING "64" | ||
33 | typedef u64 unative_t; | ||
34 | #else | ||
35 | # define NBYTES(x) ((x) * 0x01010101U) | ||
36 | # define NSIZE 4 | ||
37 | # define NSHIFT 2 | ||
38 | # define NSTRING "32" | ||
39 | typedef u32 unative_t; | ||
40 | #endif | ||
41 | |||
42 | |||
43 | |||
44 | /* | ||
45 | * IA-64 wants insane amounts of unrolling. On other architectures that | ||
46 | * is just a waste of space. | ||
47 | */ | ||
48 | #if ($# <= 8) || defined(__ia64__) | ||
49 | |||
50 | |||
51 | /* | ||
52 | * These sub-operations are separate inlines since they can sometimes be | ||
53 | * specially optimized using architecture-specific hacks. | ||
54 | */ | ||
55 | |||
56 | /* | ||
57 | * The SHLBYTE() operation shifts each byte left by 1, *not* | ||
58 | * rolling over into the next byte | ||
59 | */ | ||
60 | static inline __attribute_const__ unative_t SHLBYTE(unative_t v) | ||
61 | { | ||
62 | unative_t vv; | ||
63 | |||
64 | vv = (v << 1) & NBYTES(0xfe); | ||
65 | return vv; | ||
66 | } | ||
67 | |||
68 | /* | ||
69 | * The MASK() operation returns 0xFF in any byte for which the high | ||
70 | * bit is 1, 0x00 for any byte for which the high bit is 0. | ||
71 | */ | ||
72 | static inline __attribute_const__ unative_t MASK(unative_t v) | ||
73 | { | ||
74 | unative_t vv; | ||
75 | |||
76 | vv = v & NBYTES(0x80); | ||
77 | vv = (vv << 1) - (vv >> 7); /* Overflow on the top bit is OK */ | ||
78 | return vv; | ||
79 | } | ||
80 | |||
81 | |||
82 | static void raid6_int$#_gen_syndrome(int disks, size_t bytes, void **ptrs) | ||
83 | { | ||
84 | u8 **dptr = (u8 **)ptrs; | ||
85 | u8 *p, *q; | ||
86 | int d, z, z0; | ||
87 | |||
88 | unative_t wd$$, wq$$, wp$$, w1$$, w2$$; | ||
89 | |||
90 | z0 = disks - 3; /* Highest data disk */ | ||
91 | p = dptr[z0+1]; /* XOR parity */ | ||
92 | q = dptr[z0+2]; /* RS syndrome */ | ||
93 | |||
94 | for ( d = 0 ; d < bytes ; d += NSIZE*$# ) { | ||
95 | wq$$ = wp$$ = *(unative_t *)&dptr[z0][d+$$*NSIZE]; | ||
96 | for ( z = z0-1 ; z >= 0 ; z-- ) { | ||
97 | wd$$ = *(unative_t *)&dptr[z][d+$$*NSIZE]; | ||
98 | wp$$ ^= wd$$; | ||
99 | w2$$ = MASK(wq$$); | ||
100 | w1$$ = SHLBYTE(wq$$); | ||
101 | w2$$ &= NBYTES(0x1d); | ||
102 | w1$$ ^= w2$$; | ||
103 | wq$$ = w1$$ ^ wd$$; | ||
104 | } | ||
105 | *(unative_t *)&p[d+NSIZE*$$] = wp$$; | ||
106 | *(unative_t *)&q[d+NSIZE*$$] = wq$$; | ||
107 | } | ||
108 | } | ||
109 | |||
110 | const struct raid6_calls raid6_intx$# = { | ||
111 | raid6_int$#_gen_syndrome, | ||
112 | NULL, /* always valid */ | ||
113 | "int" NSTRING "x$#", | ||
114 | 0 | ||
115 | }; | ||
116 | |||
117 | #endif | ||