Return-Path: Subject: Re: [RFCv3 bluetooth-next 3/4] ipv6: add ipv6_addr_prefix_copy References: <1448796882-316-1-git-send-email-alex.aring@gmail.com> <1448796882-316-4-git-send-email-alex.aring@gmail.com> <1448967386.3315997.454536553.3B344491@webmail.messagingengine.com> Cc: Hannes Frederic Sowa , Alexander Aring , hideaki.yoshifuji@miraclelinux.com, kernel@pengutronix.de, mcr@sandelman.ca, lukasz.duda@nordicsemi.no, martin.gergeleit@hs-rm.de, Alexey Kuznetsov , James Morris , Hideaki YOSHIFUJI , Patrick McHardy From: =?UTF-8?B?WU9TSElGVUpJIEhpZGVha2kv5ZCJ6Jek6Iux5piO?= To: linux-wpan@vger.kernel.org, linux-bluetooth@vger.kernel.org, netdev@vger.kernel.org, "David S . Miller" Message-ID: <565D81BF.3080608@miraclelinux.com> Date: Tue, 1 Dec 2015 20:17:19 +0900 MIME-Version: 1.0 In-Reply-To: <1448967386.3315997.454536553.3B344491@webmail.messagingengine.com> Content-Type: text/plain; charset=iso-2022-jp Sender: linux-wpan-owner@vger.kernel.org List-ID: Hannes Frederic Sowa wrote: > > > On Sun, Nov 29, 2015, at 12:34, Alexander Aring wrote: >> This patch adds a static inline function ipv6_addr_prefix_copy which >> copies a ipv6 address prefix(argument pfx) into the ipv6 address prefix. >> The prefix len is given by plen as bits. This function mainly based on >> ipv6_addr_prefix which copies one address prefix from address into a new >> ipv6 address destination and zero all other address bits. >> >> The difference is that ipv6_addr_prefix_copy don't get a prefix from an >> ipv6 address, it sets a prefix to an ipv6 address with keeping other >> address bits. The use case is for context based address compression >> inside 6LoWPAN IPHC header which keeping ipv6 prefixes inside a context >> table to lookup address-bits without sending them. >> >> Cc: David S. Miller >> Cc: Alexey Kuznetsov >> Cc: James Morris >> Cc: Hideaki YOSHIFUJI >> Cc: Patrick McHardy >> Signed-off-by: Alexander Aring >> --- >> include/net/ipv6.h | 15 +++++++++++++++ >> 1 file changed, 15 insertions(+) >> >> diff --git a/include/net/ipv6.h b/include/net/ipv6.h >> index e1a10b0..cd3881e6 100644 >> --- a/include/net/ipv6.h >> +++ b/include/net/ipv6.h >> @@ -382,6 +382,21 @@ static inline void ipv6_addr_prefix(struct in6_addr >> *pfx, >> pfx->s6_addr[o] = addr->s6_addr[o] & (0xff00 >> b); >> } >> >> +static inline void ipv6_addr_prefix_copy(struct in6_addr *addr, >> + const struct in6_addr *pfx, >> + int plen) >> +{ >> + /* caller must guarantee 0 <= plen <= 128 */ >> + int o = plen >> 3, >> + b = plen & 0x7; >> + >> + memcpy(addr->s6_addr, pfx, o); >> + if (b != 0) { >> + addr->s6_addr[o] &= ~(0xff00 >> b); >> + addr->s6_addr[o] |= (pfx->s6_addr[o] & (0xff00 >> b)); >> + } >> +} >> + > > Acked-by: Hannes Frederic Sowa Acked-by: YOSHIFUJI Hideaki > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- 吉藤英明 ミラクル・リナックス株式会社 技術本部 サポート部