Return-Path: From: "Duda, Lukasz" To: Alexander Aring , "linux-wpan@vger.kernel.org" CC: "linux-bluetooth@vger.kernel.org" , "netdev@vger.kernel.org" , "kernel@pengutronix.de" , "mcr@sandelman.ca" , "martin.gergeleit@hs-rm.de" , "David S . Miller" , Alexey Kuznetsov , James Morris , Hideaki YOSHIFUJI , "Patrick McHardy" Subject: RE: [RFCv3 bluetooth-next 3/4] ipv6: add ipv6_addr_prefix_copy Date: Tue, 1 Dec 2015 11:51:25 +0000 Message-ID: References: <1448796882-316-1-git-send-email-alex.aring@gmail.com> <1448796882-316-4-git-send-email-alex.aring@gmail.com> In-Reply-To: <1448796882-316-4-git-send-email-alex.aring@gmail.com> Content-Type: text/plain; charset="iso-8859-2" MIME-Version: 1.0 Sender: linux-bluetooth-owner@vger.kernel.org List-ID: > -----Original Message----- > From: Alexander Aring [mailto:alex.aring@gmail.com] > Sent: Sunday, November 29, 2015 12:35 > To: linux-wpan@vger.kernel.org > Cc: linux-bluetooth@vger.kernel.org; netdev@vger.kernel.org; > kernel@pengutronix.de; mcr@sandelman.ca; Duda, Lukasz; > martin.gergeleit@hs-rm.de; Alexander Aring; David S . Miller; Alexey > Kuznetsov; James Morris; Hideaki YOSHIFUJI; Patrick McHardy > Subject: [RFCv3 bluetooth-next 3/4] ipv6: add ipv6_addr_prefix_copy > > 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)); > + } > +} > + > static inline void __ipv6_addr_set_half(__be32 *addr, > __be32 wh, __be32 wl) > { > -- > 2.6.1 Acked-by: ?ukasz Duda