From mboxrd@z Thu Jan 1 00:00:00 1970 From: roopa@cumulusnetworks.com Subject: [RFC PATCH iproute2] link dump filter Date: Thu, 3 Jul 2014 16:07:15 -0700 Message-ID: <1404428835-21011-1-git-send-email-roopa@cumulusnetworks.com> Cc: shm@cumulusnetworks.com, nolan@cumulusnetworks.com, sfeldma@cumulusnetworks.com, jhs@mojatatu.com To: davem@davemloft.net, stephen@networkplumber.org, netdev@vger.kernel.org, roopa@cumulusnetworks.com Return-path: Received: from ext3.cumulusnetworks.com ([198.211.106.187]:36255 "EHLO ext3.cumulusnetworks.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752275AbaGCXGo (ORCPT ); Thu, 3 Jul 2014 19:06:44 -0400 Sender: netdev-owner@vger.kernel.org List-ID: From: Roopa Prabhu This patch avoids a full link wildump request when the user has specified a single link. Uses RTM_GETLINK without the NLM_F_DUMP flag. This helps on a system with large number of interfaces. This patch currently only uses the link ifindex in the filter. Hoping to provide a subsequent kernel patch to do link dump filtering on other attributes in the kernel. In iplink_get, to be safe, this patch currently sets the answer buffer size to the max size that libnetlink rtnl_talk can copy. The current api does not seem to provide a way to indicate the answer buf size. Signed-off-by: Roopa Prabhu --- ip/ip_common.h | 1 + ip/ipaddress.c | 20 +++++++++++++++++--- ip/iplink.c | 32 ++++++++++++++++++++++++++++++++ 3 files changed, 50 insertions(+), 3 deletions(-) diff --git a/ip/ip_common.h b/ip/ip_common.h index ac1e4c1..e56d1ac 100644 --- a/ip/ip_common.h +++ b/ip/ip_common.h @@ -51,6 +51,7 @@ extern int do_ipl2tp(int argc, char **argv); extern int do_tcp_metrics(int argc, char **argv); extern int do_ipnetconf(int argc, char **argv); extern int do_iptoken(int argc, char **argv); +extern int iplink_get(unsigned int flags, char *name, __u32 filt_mask); static inline int rtm_get_table(struct rtmsg *r, struct rtattr **tb) { diff --git a/ip/ipaddress.c b/ip/ipaddress.c index 8138e86..d111fab 100644 --- a/ip/ipaddress.c +++ b/ip/ipaddress.c @@ -1241,9 +1241,23 @@ static int ipaddr_list_flush_or_save(int argc, char **argv, int action) exit(0); } - if (rtnl_wilddump_request(&rth, preferred_family, RTM_GETLINK) < 0) { - perror("Cannot send dump request"); - exit(1); + if (filter_dev && filter.group == -1 && do_link == 1) { + /* + * If only filter_dev present and none of the other + * link filters are present, use RTM_GETLINK to get + * the link device + */ + if (iplink_get(0, filter_dev, RTEXT_FILTER_VF) < 0) { + perror("Cannot send link get request"); + exit(1); + } + exit(0); + } else { + if (rtnl_wilddump_request(&rth, preferred_family, + RTM_GETLINK) < 0) { + perror("Cannot send dump request"); + exit(1); + } } if (rtnl_dump_filter(&rth, store_nlmsg, &linfo) < 0) { diff --git a/ip/iplink.c b/ip/iplink.c index 0d020ef..7ac2813 100644 --- a/ip/iplink.c +++ b/ip/iplink.c @@ -703,6 +703,38 @@ static int iplink_modify(int cmd, unsigned int flags, int argc, char **argv) return 0; } +int iplink_get(unsigned int flags, char *name, __u32 filt_mask) +{ + int len; + struct iplink_req req; + char answer[16384]; + + memset(&req, 0, sizeof(req)); + + req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)); + req.n.nlmsg_flags = NLM_F_REQUEST|flags; + req.n.nlmsg_type = RTM_GETLINK; + req.i.ifi_family = preferred_family; + + if (name) { + len = strlen(name) + 1; + if (len == 1) + invarg("\"\" is not a valid device identifier\n", + "name"); + if (len > IFNAMSIZ) + invarg("\"name\" too long\n", name); + addattr_l(&req.n, sizeof(req), IFLA_IFNAME, name, len); + } + addattr32(&req.n, sizeof(req), IFLA_EXT_MASK, filt_mask); + + if (rtnl_talk(&rth, &req.n, 0, 0, (struct nlmsghdr *)answer) < 0) + return -2; + + print_linkinfo(NULL, (struct nlmsghdr *)answer, stdout); + + return 0; +} + #if IPLINK_IOCTL_COMPAT static int get_ctl_fd(void) { -- 1.7.10.4