From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50481) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1apH5N-0007bm-Mr for qemu-devel@nongnu.org; Sun, 10 Apr 2016 11:15:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1apH5K-00086B-EU for qemu-devel@nongnu.org; Sun, 10 Apr 2016 11:15:37 -0400 Received: from mail-wm0-x233.google.com ([2a00:1450:400c:c09::233]:34729) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1apH5J-00085i-TW for qemu-devel@nongnu.org; Sun, 10 Apr 2016 11:15:34 -0400 Received: by mail-wm0-x233.google.com with SMTP id l6so116303071wml.1 for ; Sun, 10 Apr 2016 08:15:33 -0700 (PDT) From: Dmitry Fleytman Date: Sun, 10 Apr 2016 18:14:55 +0300 Message-Id: <1460301305-5321-7-git-send-email-dmitry@daynix.com> In-Reply-To: <1460301305-5321-1-git-send-email-dmitry@daynix.com> References: <1460301305-5321-1-git-send-email-dmitry@daynix.com> Subject: [Qemu-devel] [PATCH v4 06/16] net: Introduce Toeplitz hash calculator List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Jason Wang , "Michael S. Tsirkin" , Yan Vugenfirer , Leonid Bloch , Shmulik Ladkani From: Dmitry Fleytman Signed-off-by: Dmitry Fleytman Signed-off-by: Leonid Bloch --- include/net/checksum.h | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) diff --git a/include/net/checksum.h b/include/net/checksum.h index 7de1acb..dd8b4f6 100644 --- a/include/net/checksum.h +++ b/include/net/checksum.h @@ -18,6 +18,7 @@ #ifndef QEMU_NET_CHECKSUM_H #define QEMU_NET_CHECKSUM_H +#include "qemu/bswap.h" struct iovec; uint32_t net_checksum_add_cont(int len, uint8_t *buf, int seq); @@ -50,4 +51,48 @@ uint32_t net_checksum_add_iov(const struct iovec *iov, const unsigned int iov_cnt, uint32_t iov_off, uint32_t size); +typedef struct toeplitz_key_st { + uint32_t leftmost_32_bits; + uint8_t *next_byte; +} net_toeplitz_key; + +static inline +void net_toeplitz_key_init(net_toeplitz_key *key, uint8_t *key_bytes) +{ + key->leftmost_32_bits = be32_to_cpu(*(uint32_t *)key_bytes); + key->next_byte = key_bytes + sizeof(uint32_t); +} + +static inline +void net_toeplitz_add(uint32_t *result, + uint8_t *input, + uint32_t len, + net_toeplitz_key *key) +{ + register uint32_t accumulator = *result; + register uint32_t leftmost_32_bits = key->leftmost_32_bits; + register uint32_t byte; + + for (byte = 0; byte < len; byte++) { + register uint8_t input_byte = input[byte]; + register uint8_t key_byte = *(key->next_byte++); + register uint8_t bit; + + for (bit = 0; bit < 8; bit++) { + if (input_byte & (1 << 7)) { + accumulator ^= leftmost_32_bits; + } + + leftmost_32_bits = + (leftmost_32_bits << 1) | ((key_byte & (1 << 7)) >> 7); + + input_byte <<= 1; + key_byte <<= 1; + } + } + + key->leftmost_32_bits = leftmost_32_bits; + *result = accumulator; +} + #endif /* QEMU_NET_CHECKSUM_H */ -- 2.5.0