From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vlad Yasevich Subject: Re: [PATCH] sctp: remove unnecessary byteshifting, calculate crc in big-endian Date: Wed, 09 Jul 2008 16:59:36 -0400 Message-ID: <487526B8.70903@hp.com> References: <1215133995.16647.51.camel@brick> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: David Miller , linux-netdev , Andrew Morton To: Harvey Harrison Return-path: Received: from g5t0009.atlanta.hp.com ([15.192.0.46]:1707 "EHLO g5t0009.atlanta.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753400AbYGIU7j (ORCPT ); Wed, 9 Jul 2008 16:59:39 -0400 In-Reply-To: <1215133995.16647.51.camel@brick> Sender: netdev-owner@vger.kernel.org List-ID: Harvey Harrison wrote: > Signed-off-by: Harvey Harrison > --- > include/net/sctp/checksum.h | 23 ++++++++++++++--------- > net/ipv4/netfilter/nf_nat_proto_sctp.c | 4 ++-- > net/sctp/input.c | 4 ++-- > net/sctp/output.c | 4 ++-- > 4 files changed, 20 insertions(+), 15 deletions(-) > > diff --git a/include/net/sctp/checksum.h b/include/net/sctp/checksum.h > index ba75c67..b799fb2 100644 > --- a/include/net/sctp/checksum.h > +++ b/include/net/sctp/checksum.h > @@ -46,9 +46,14 @@ > #include > #include > > -static inline __u32 sctp_start_cksum(__u8 *buffer, __u16 length) > +static inline __be32 sctp_crc32c(__be32 crc, u8 *buffer, u16 length) > { > - __u32 crc = ~(__u32) 0; > + return (__force __be32)crc32c((__force u32)crc, buffer, length); > +} > + > +static inline __be32 sctp_start_cksum(__u8 *buffer, __u16 length) > +{ > + __be32 crc = ~cpu_to_be32(0); > __u8 zero[sizeof(__u32)] = {0}; > > /* Optimize this routine to be SCTP specific, knowing how > @@ -56,23 +61,23 @@ static inline __u32 sctp_start_cksum(__u8 *buffer, __u16 length) > */ > > /* Calculate CRC up to the checksum. */ > - crc = crc32c(crc, buffer, sizeof(struct sctphdr) - sizeof(__u32)); > + crc = sctp_crc32c(crc, buffer, sizeof(struct sctphdr) - sizeof(__u32)); > > /* Skip checksum field of the header. */ > - crc = crc32c(crc, zero, sizeof(__u32)); > + crc = sctp_crc32c(crc, zero, sizeof(__u32)); > > /* Calculate the rest of the CRC. */ > - crc = crc32c(crc, &buffer[sizeof(struct sctphdr)], > + crc = sctp_crc32c(crc, &buffer[sizeof(struct sctphdr)], > length - sizeof(struct sctphdr)); > return crc; > } > > -static inline __u32 sctp_update_cksum(__u8 *buffer, __u16 length, __u32 crc32) > +static inline __be32 sctp_update_cksum(__u8 *buffer, __u16 length, __be32 crc32) > { > - return crc32c(crc32, buffer, length); > + return sctp_crc32c(crc32, buffer, length); > } > > -static inline __u32 sctp_end_cksum(__u32 crc32) > +static inline __be32 sctp_end_cksum(__be32 crc32) > { > - return ntohl(~crc32); > + return ~crc32; > } > diff --git a/net/ipv4/netfilter/nf_nat_proto_sctp.c b/net/ipv4/netfilter/nf_nat_proto_sctp.c > index 82e4c0e..65e470b 100644 > --- a/net/ipv4/netfilter/nf_nat_proto_sctp.c > +++ b/net/ipv4/netfilter/nf_nat_proto_sctp.c > @@ -36,7 +36,7 @@ sctp_manip_pkt(struct sk_buff *skb, > sctp_sctphdr_t *hdr; > unsigned int hdroff = iphdroff + iph->ihl*4; > __be32 oldip, newip; > - u32 crc32; > + __be32 crc32; > > if (!skb_make_writable(skb, hdroff + sizeof(*hdr))) > return false; > @@ -61,7 +61,7 @@ sctp_manip_pkt(struct sk_buff *skb, > crc32 = sctp_update_cksum((u8 *)skb->data, skb_headlen(skb), > crc32); > crc32 = sctp_end_cksum(crc32); > - hdr->checksum = htonl(crc32); > + hdr->checksum = crc32; > > return true; > } > diff --git a/net/sctp/input.c b/net/sctp/input.c > index d354a23..463d529 100644 > --- a/net/sctp/input.c > +++ b/net/sctp/input.c > @@ -82,8 +82,8 @@ static inline int sctp_rcv_checksum(struct sk_buff *skb) > { > struct sk_buff *list = skb_shinfo(skb)->frag_list; > struct sctphdr *sh = sctp_hdr(skb); > - __u32 cmp = ntohl(sh->checksum); > - __u32 val = sctp_start_cksum((__u8 *)sh, skb_headlen(skb)); > + __be32 cmp = sh->checksum; > + __be32 val = sctp_start_cksum((__u8 *)sh, skb_headlen(skb)); > > for (; list; list = list->next) > val = sctp_update_cksum((__u8 *)list->data, skb_headlen(list), > diff --git a/net/sctp/output.c b/net/sctp/output.c > index abcd00d..e2158ad 100644 > --- a/net/sctp/output.c > +++ b/net/sctp/output.c > @@ -364,7 +364,7 @@ int sctp_packet_transmit(struct sctp_packet *packet) > struct sctp_transport *tp = packet->transport; > struct sctp_association *asoc = tp->asoc; > struct sctphdr *sh; > - __u32 crc32 = 0; > + __be32 crc32 = cpu_to_be32(0); Does this actually do anything? Otherwise, good clean-up. Thanks -vlad > struct sk_buff *nskb; > struct sctp_chunk *chunk, *tmp; > struct sock *sk; > @@ -537,7 +537,7 @@ int sctp_packet_transmit(struct sctp_packet *packet) > /* 3) Put the resultant value into the checksum field in the > * common header, and leave the rest of the bits unchanged. > */ > - sh->checksum = htonl(crc32); > + sh->checksum = crc32; > > /* IP layer ECN support > * From RFC 2481