diff options
Diffstat (limited to 'fs/ceph/crush/hash.c')
-rw-r--r-- | fs/ceph/crush/hash.c | 149 |
1 files changed, 0 insertions, 149 deletions
diff --git a/fs/ceph/crush/hash.c b/fs/ceph/crush/hash.c deleted file mode 100644 index 5873aed..0000000 --- a/fs/ceph/crush/hash.c +++ /dev/null @@ -1,149 +0,0 @@ - -#include <linux/types.h> -#include "hash.h" - -/* - * Robert Jenkins' function for mixing 32-bit values - * http://burtleburtle.net/bob/hash/evahash.html - * a, b = random bits, c = input and output - */ -#define crush_hashmix(a, b, c) do { \ - a = a-b; a = a-c; a = a^(c>>13); \ - b = b-c; b = b-a; b = b^(a<<8); \ - c = c-a; c = c-b; c = c^(b>>13); \ - a = a-b; a = a-c; a = a^(c>>12); \ - b = b-c; b = b-a; b = b^(a<<16); \ - c = c-a; c = c-b; c = c^(b>>5); \ - a = a-b; a = a-c; a = a^(c>>3); \ - b = b-c; b = b-a; b = b^(a<<10); \ - c = c-a; c = c-b; c = c^(b>>15); \ - } while (0) - -#define crush_hash_seed 1315423911 - -static __u32 crush_hash32_rjenkins1(__u32 a) -{ - __u32 hash = crush_hash_seed ^ a; - __u32 b = a; - __u32 x = 231232; - __u32 y = 1232; - crush_hashmix(b, x, hash); - crush_hashmix(y, a, hash); - return hash; -} - -static __u32 crush_hash32_rjenkins1_2(__u32 a, __u32 b) -{ - __u32 hash = crush_hash_seed ^ a ^ b; - __u32 x = 231232; - __u32 y = 1232; - crush_hashmix(a, b, hash); - crush_hashmix(x, a, hash); - crush_hashmix(b, y, hash); - return hash; -} - -static __u32 crush_hash32_rjenkins1_3(__u32 a, __u32 b, __u32 c) -{ - __u32 hash = crush_hash_seed ^ a ^ b ^ c; - __u32 x = 231232; - __u32 y = 1232; - crush_hashmix(a, b, hash); - crush_hashmix(c, x, hash); - crush_hashmix(y, a, hash); - crush_hashmix(b, x, hash); - crush_hashmix(y, c, hash); - return hash; -} - -static __u32 crush_hash32_rjenkins1_4(__u32 a, __u32 b, __u32 c, __u32 d) -{ - __u32 hash = crush_hash_seed ^ a ^ b ^ c ^ d; - __u32 x = 231232; - __u32 y = 1232; - crush_hashmix(a, b, hash); - crush_hashmix(c, d, hash); - crush_hashmix(a, x, hash); - crush_hashmix(y, b, hash); - crush_hashmix(c, x, hash); - crush_hashmix(y, d, hash); - return hash; -} - -static __u32 crush_hash32_rjenkins1_5(__u32 a, __u32 b, __u32 c, __u32 d, - __u32 e) -{ - __u32 hash = crush_hash_seed ^ a ^ b ^ c ^ d ^ e; - __u32 x = 231232; - __u32 y = 1232; - crush_hashmix(a, b, hash); - crush_hashmix(c, d, hash); - crush_hashmix(e, x, hash); - crush_hashmix(y, a, hash); - crush_hashmix(b, x, hash); - crush_hashmix(y, c, hash); - crush_hashmix(d, x, hash); - crush_hashmix(y, e, hash); - return hash; -} - - -__u32 crush_hash32(int type, __u32 a) -{ - switch (type) { - case CRUSH_HASH_RJENKINS1: - return crush_hash32_rjenkins1(a); - default: - return 0; - } -} - -__u32 crush_hash32_2(int type, __u32 a, __u32 b) -{ - switch (type) { - case CRUSH_HASH_RJENKINS1: - return crush_hash32_rjenkins1_2(a, b); - default: - return 0; - } -} - -__u32 crush_hash32_3(int type, __u32 a, __u32 b, __u32 c) -{ - switch (type) { - case CRUSH_HASH_RJENKINS1: - return crush_hash32_rjenkins1_3(a, b, c); - default: - return 0; - } -} - -__u32 crush_hash32_4(int type, __u32 a, __u32 b, __u32 c, __u32 d) -{ - switch (type) { - case CRUSH_HASH_RJENKINS1: - return crush_hash32_rjenkins1_4(a, b, c, d); - default: - return 0; - } -} - -__u32 crush_hash32_5(int type, __u32 a, __u32 b, __u32 c, __u32 d, __u32 e) -{ - switch (type) { - case CRUSH_HASH_RJENKINS1: - return crush_hash32_rjenkins1_5(a, b, c, d, e); - default: - return 0; - } -} - -const char *crush_hash_name(int type) -{ - switch (type) { - case CRUSH_HASH_RJENKINS1: - return "rjenkins1"; - default: - return "unknown"; - } -} |