1#ifdef __KERNEL__
2# include <linux/crush/hash.h>
3#else
4# include "hash.h"
5#endif
6
7
8
9
10
11
12#define crush_hashmix(a, b, c) do { \
13 a = a-b; a = a-c; a = a^(c>>13); \
14 b = b-c; b = b-a; b = b^(a<<8); \
15 c = c-a; c = c-b; c = c^(b>>13); \
16 a = a-b; a = a-c; a = a^(c>>12); \
17 b = b-c; b = b-a; b = b^(a<<16); \
18 c = c-a; c = c-b; c = c^(b>>5); \
19 a = a-b; a = a-c; a = a^(c>>3); \
20 b = b-c; b = b-a; b = b^(a<<10); \
21 c = c-a; c = c-b; c = c^(b>>15); \
22 } while (0)
23
24#define crush_hash_seed 1315423911
25
26static __u32 crush_hash32_rjenkins1(__u32 a)
27{
28 __u32 hash = crush_hash_seed ^ a;
29 __u32 b = a;
30 __u32 x = 231232;
31 __u32 y = 1232;
32 crush_hashmix(b, x, hash);
33 crush_hashmix(y, a, hash);
34 return hash;
35}
36
37static __u32 crush_hash32_rjenkins1_2(__u32 a, __u32 b)
38{
39 __u32 hash = crush_hash_seed ^ a ^ b;
40 __u32 x = 231232;
41 __u32 y = 1232;
42 crush_hashmix(a, b, hash);
43 crush_hashmix(x, a, hash);
44 crush_hashmix(b, y, hash);
45 return hash;
46}
47
48static __u32 crush_hash32_rjenkins1_3(__u32 a, __u32 b, __u32 c)
49{
50 __u32 hash = crush_hash_seed ^ a ^ b ^ c;
51 __u32 x = 231232;
52 __u32 y = 1232;
53 crush_hashmix(a, b, hash);
54 crush_hashmix(c, x, hash);
55 crush_hashmix(y, a, hash);
56 crush_hashmix(b, x, hash);
57 crush_hashmix(y, c, hash);
58 return hash;
59}
60
61static __u32 crush_hash32_rjenkins1_4(__u32 a, __u32 b, __u32 c, __u32 d)
62{
63 __u32 hash = crush_hash_seed ^ a ^ b ^ c ^ d;
64 __u32 x = 231232;
65 __u32 y = 1232;
66 crush_hashmix(a, b, hash);
67 crush_hashmix(c, d, hash);
68 crush_hashmix(a, x, hash);
69 crush_hashmix(y, b, hash);
70 crush_hashmix(c, x, hash);
71 crush_hashmix(y, d, hash);
72 return hash;
73}
74
75static __u32 crush_hash32_rjenkins1_5(__u32 a, __u32 b, __u32 c, __u32 d,
76 __u32 e)
77{
78 __u32 hash = crush_hash_seed ^ a ^ b ^ c ^ d ^ e;
79 __u32 x = 231232;
80 __u32 y = 1232;
81 crush_hashmix(a, b, hash);
82 crush_hashmix(c, d, hash);
83 crush_hashmix(e, x, hash);
84 crush_hashmix(y, a, hash);
85 crush_hashmix(b, x, hash);
86 crush_hashmix(y, c, hash);
87 crush_hashmix(d, x, hash);
88 crush_hashmix(y, e, hash);
89 return hash;
90}
91
92
93__u32 crush_hash32(int type, __u32 a)
94{
95 switch (type) {
96 case CRUSH_HASH_RJENKINS1:
97 return crush_hash32_rjenkins1(a);
98 default:
99 return 0;
100 }
101}
102
103__u32 crush_hash32_2(int type, __u32 a, __u32 b)
104{
105 switch (type) {
106 case CRUSH_HASH_RJENKINS1:
107 return crush_hash32_rjenkins1_2(a, b);
108 default:
109 return 0;
110 }
111}
112
113__u32 crush_hash32_3(int type, __u32 a, __u32 b, __u32 c)
114{
115 switch (type) {
116 case CRUSH_HASH_RJENKINS1:
117 return crush_hash32_rjenkins1_3(a, b, c);
118 default:
119 return 0;
120 }
121}
122
123__u32 crush_hash32_4(int type, __u32 a, __u32 b, __u32 c, __u32 d)
124{
125 switch (type) {
126 case CRUSH_HASH_RJENKINS1:
127 return crush_hash32_rjenkins1_4(a, b, c, d);
128 default:
129 return 0;
130 }
131}
132
133__u32 crush_hash32_5(int type, __u32 a, __u32 b, __u32 c, __u32 d, __u32 e)
134{
135 switch (type) {
136 case CRUSH_HASH_RJENKINS1:
137 return crush_hash32_rjenkins1_5(a, b, c, d, e);
138 default:
139 return 0;
140 }
141}
142
143const char *crush_hash_name(int type)
144{
145 switch (type) {
146 case CRUSH_HASH_RJENKINS1:
147 return "rjenkins1";
148 default:
149 return "unknown";
150 }
151}
152
