Subject: Re: [PATCH net-next] fib_trie: Send RTM_DELROUTE when link goes down

From: Sergei Shtylyov <[email-masked]>
Date: Thu, 17 Oct 2013 17:43:21 +0400

Hello.

On 17-10-2013 15:13, Kristian Evensen wrote:

> From: Kristian Evensen <[email-masked]>

> When a link is set as down using for example "ip link set dev X down", routes
> are deleted, but RTM_DELROUTE messages are not sent to RTNLGRP_IPV4_ROUTE. This
> patch makes trie_flush_list() send a RTM_DELROUTE for each route that is
> removed, and makes rtnelink route deletion behavior consistent across commands.
> The parameter lists for trie_flush_list() and trie_flush_leaf() are expanded to
> include required information otherwise unavailable in trie_flush_list().

> One use case that is simplified by this patch is IPv4 WAN connection monitoring.
> Instead of listening for and handling both RTM_*ROUTE and RTM_*LINK-messages, it
> is sufficient to handle RTM_*ROUTE.

> Signed-off-by: Kristian Evensen <[email-masked]>

> ---
>   net/ipv4/fib_trie.c | 16 ++++++++++++----
>   1 file changed, 12 insertions(+), 4 deletions(-)

> diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
> index ec9a9ef..acd5b3b 100644
> --- a/net/ipv4/fib_trie.c
> +++ b/net/ipv4/fib_trie.c
> @@ -1698,15 +1698,23 @@ int fib_table_delete(struct fib_table *tb, struct fib_config *cfg)
>   	return 0;
>   }
>
> -static int trie_flush_list(struct list_head *head)
> +static int trie_flush_list(struct list_head *head, u32 tb_id, t_key key,
> +		int plen)

    The continuation line should start right under *struct* on the first line, 
according to the networking coding style.

>   {
>   	struct fib_alias *fa, *fa_node;
>   	int found = 0;
> +	struct nl_info cfg;
> +
> +	memset(&cfg, 0, sizeof(cfg));
>
>   	list_for_each_entry_safe(fa, fa_node, head, fa_list) {
>   		struct fib_info *fi = fa->fa_info;
>
>   		if (fi && (fi->fib_flags & RTNH_F_DEAD)) {
> +			cfg.nl_net = fi->fib_net;
> +			rtmsg_fib(RTM_DELROUTE, htonl(key), fa, plen, tb_id,
> +					&cfg, 0);

    Here the line should start right under RTM_DELROUTE.

WBR, Sergei