From: zhangchen <zhangchen.f...@cn.fujitsu.com> This used by colo-proxy to save and lookup connection info
Signed-off-by: zhangchen <zhangchen.f...@cn.fujitsu.com> --- include/qemu/jhash.h | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 include/qemu/jhash.h diff --git a/include/qemu/jhash.h b/include/qemu/jhash.h new file mode 100644 index 0000000..f6cc7b3 --- /dev/null +++ b/include/qemu/jhash.h @@ -0,0 +1,52 @@ +/* + * COarse-grain LOck-stepping Virtual Machines for Non-stop Service (COLO) + * (a.k.a. Fault Tolerance or Continuous Replication) + * + * Copyright (c) 2015 HUAWEI TECHNOLOGIES CO., LTD. + * Copyright (c) 2015 FUJITSU LIMITED + * Copyright (c) 2015 Intel Corporation + * + * Author: Zhang Chen <zhangchen.f...@cn.fujitsu.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or + * later. See the COPYING file in the top-level directory. + */ + +#ifndef QEMU_JHASH_H__ +#define QEMU_JHASH_H__ + +/* + * hashtable relation copy from linux kernel jhash + */ +static inline uint32_t rol32(uint32_t word, unsigned int shift) +{ + return (word << shift) | (word >> (32 - shift)); +} + +/* __jhash_mix -- mix 3 32-bit values reversibly. */ +#define __jhash_mix(a, b, c) \ +{ \ + a -= c; a ^= rol32(c, 4); c += b; \ + b -= a; b ^= rol32(a, 6); a += c; \ + c -= b; c ^= rol32(b, 8); b += a; \ + a -= c; a ^= rol32(c, 16); c += b; \ + b -= a; b ^= rol32(a, 19); a += c; \ + c -= b; c ^= rol32(b, 4); b += a; \ +} + +/* __jhash_final - final mixing of 3 32-bit values (a,b,c) into c */ +#define __jhash_final(a, b, c) \ +{ \ + c ^= b; c -= rol32(b, 14); \ + a ^= c; a -= rol32(c, 11); \ + b ^= a; b -= rol32(a, 25); \ + c ^= b; c -= rol32(b, 16); \ + a ^= c; a -= rol32(c, 4); \ + b ^= a; b -= rol32(a, 14); \ + c ^= b; c -= rol32(b, 24); \ +} + +/* An arbitrary initial parameter */ +#define JHASH_INITVAL 0xdeadbeef + +#endif /* QEMU_JHASH_H__ */ -- 1.9.1