From f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74 Mon Sep 17 00:00:00 2001 From: David Ahern Date: Mon, 3 Jun 2019 20:19:52 -0700 Subject: ipv6: Plumb support for nexthop object in a fib6_info Add struct nexthop and nh_list list_head to fib6_info. nh_list is the fib6_info side of the nexthop <-> fib_info relationship. Since a fib6_info referencing a nexthop object can not have 'sibling' entries (the old way of doing multipath routes), the nh_list is a union with fib6_siblings. Add f6i_list list_head to 'struct nexthop' to track fib6_info entries using a nexthop instance. Update __remove_nexthop_fib to walk f6_list and delete fib entries using the nexthop. Add a few nexthop helpers for use when a nexthop is added to fib6_info: - nexthop_fib6_nh - return first fib6_nh in a nexthop object - fib6_info_nh_dev moved to nexthop.h and updated to use nexthop_fib6_nh if the fib6_info references a nexthop object - nexthop_path_fib6_result - similar to ipv4, select a path within a multipath nexthop object. If the nexthop is a blackhole, set fib6_result type to RTN_BLACKHOLE, and set the REJECT flag Update the fib6_info references to check for nh and take a different path as needed: - rt6_qualify_for_ecmp - if a fib entry uses a nexthop object it can NOT be coalesced with other fib entries into a multipath route - rt6_duplicate_nexthop - use nexthop_cmp if either fib6_info references a nexthop - addrconf (host routes), RA's and info entries (anything configured via ndisc) does not use nexthop objects - fib6_info_destroy_rcu - put reference to nexthop object - fib6_purge_rt - drop fib6_info from f6i_list - fib6_select_path - update to use the new nexthop_path_fib6_result when fib entry uses a nexthop object - rt6_device_match - update to catch use of nexthop object as a blackhole and set fib6_type and flags. - ip6_route_info_create - don't add space for fib6_nh if fib entry is going to reference a nexthop object, take a reference to nexthop object, disallow use of source routing - rt6_nlmsg_size - add space for RTA_NH_ID - add rt6_fill_node_nexthop to add nexthop data on a dump As with ipv4, most of the changes push existing code into the else branch of whether the fib entry uses a nexthop object. Update the nexthop code to walk f6i_list on a nexthop deleted to remove fib entries referencing it. Signed-off-by: David Ahern Signed-off-by: David S. Miller --- net/ipv6/ip6_fib.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) (limited to 'net/ipv6/ip6_fib.c') diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index cdfb8500ccae..02feda73a98e 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -159,6 +159,7 @@ struct fib6_info *fib6_info_alloc(gfp_t gfp_flags, bool with_fib6_nh) if (!f6i) return NULL; + /* fib6_siblings is a union with nh_list, so this initializes both */ INIT_LIST_HEAD(&f6i->fib6_siblings); refcount_set(&f6i->fib6_ref, 1); @@ -171,7 +172,11 @@ void fib6_info_destroy_rcu(struct rcu_head *head) WARN_ON(f6i->fib6_node); - fib6_nh_release(f6i->fib6_nh); + if (f6i->nh) + nexthop_put(f6i->nh); + else + fib6_nh_release(f6i->fib6_nh); + ip_fib_metrics_put(f6i->fib6_metrics); kfree(f6i); } @@ -927,6 +932,9 @@ static void fib6_purge_rt(struct fib6_info *rt, struct fib6_node *fn, fib6_drop_pcpu_from(rt, table); + if (rt->nh && !list_empty(&rt->nh_list)) + list_del_init(&rt->nh_list); + if (refcount_read(&rt->fib6_ref) != 1) { /* This route is used as dummy address holder in some split * nodes. It is not leaked, but it still holds other resources, @@ -1334,6 +1342,8 @@ int fib6_add(struct fib6_node *root, struct fib6_info *rt, err = fib6_add_rt2node(fn, rt, info, extack); if (!err) { + if (rt->nh) + list_add(&rt->nh_list, &rt->nh->f6i_list); __fib6_update_sernum_upto_root(rt, sernum); fib6_start_gc(info->nl_net, rt); } @@ -2295,9 +2305,13 @@ static int ipv6_route_seq_show(struct seq_file *seq, void *v) { struct fib6_info *rt = v; struct ipv6_route_iter *iter = seq->private; + struct fib6_nh *fib6_nh = rt->fib6_nh; unsigned int flags = rt->fib6_flags; const struct net_device *dev; + if (rt->nh) + fib6_nh = nexthop_fib6_nh(rt->nh); + seq_printf(seq, "%pi6 %02x ", &rt->fib6_dst.addr, rt->fib6_dst.plen); #ifdef CONFIG_IPV6_SUBTREES @@ -2305,14 +2319,14 @@ static int ipv6_route_seq_show(struct seq_file *seq, void *v) #else seq_puts(seq, "00000000000000000000000000000000 00 "); #endif - if (rt->fib6_nh->fib_nh_gw_family) { + if (fib6_nh->fib_nh_gw_family) { flags |= RTF_GATEWAY; - seq_printf(seq, "%pi6", &rt->fib6_nh->fib_nh_gw6); + seq_printf(seq, "%pi6", &fib6_nh->fib_nh_gw6); } else { seq_puts(seq, "00000000000000000000000000000000"); } - dev = rt->fib6_nh->fib_nh_dev; + dev = fib6_nh->fib_nh_dev; seq_printf(seq, " %08x %08x %08x %08x %8s\n", rt->fib6_metric, refcount_read(&rt->fib6_ref), 0, flags, dev ? dev->name : ""); -- cgit v1.2.3