Commit e1fa6d21 authored by Florian Westphal's avatar Florian Westphal Committed by David S. Miller
Browse files

rtnetlink: call rtnl_calcit directly 



There is only a single place in the kernel that regisers the "calcit"
callback (to determine min allocation for dumps).

This is in rtnetlink.c for PF_UNSPEC RTM_GETLINK.
The function that checks for calcit presence at run time will first check
the requested family (which will always fail for !PF_UNSPEC as no callsite
registers this), then falls back to checking PF_UNSPEC.

Therefore we can just check if type is RTM_GETLINK and then do a direct
call.  Because of fallback to PF_UNSPEC all RTM_GETLINK types used this
regardless of family.

This has the advantage that we don't need to allocate space for
the function pointer for all the other families.

A followup patch will drop the calcit function pointer from the
rtnl_link callback structure.

Signed-off-by: default avatarFlorian Westphal <fw@strlen.de>
Reviewed-by: default avatarHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 078295fb

net/core/rtnetlink.c

+4 −25
Original line number Diff line number Diff line
@@ -62,7 +62,6 @@ 
struct rtnl_link {

	rtnl_doit_func		doit;

	rtnl_dumpit_func	dumpit;

	rtnl_calcit_func 	calcit;

};



static DEFINE_MUTEX(rtnl_mutex);
@@ -173,21 +172,6 @@ static rtnl_dumpit_func rtnl_get_dumpit(int protocol, int msgindex) 
	return tab[msgindex].dumpit;

}



static rtnl_calcit_func rtnl_get_calcit(int protocol, int msgindex)

{

	struct rtnl_link *tab;



	if (protocol <= RTNL_FAMILY_MAX)

		tab = rtnl_msg_handlers[protocol];

	else

		tab = NULL;



	if (tab == NULL || tab[msgindex].calcit == NULL)

		tab = rtnl_msg_handlers[PF_UNSPEC];



	return tab[msgindex].calcit;

}



/**

 * __rtnl_register - Register a rtnetlink message type

 * @protocol: Protocol family or PF_UNSPEC
@@ -231,9 +215,6 @@ int __rtnl_register(int protocol, int msgtype, 
	if (dumpit)

		tab[msgindex].dumpit = dumpit;



	if (calcit)

		tab[msgindex].calcit = calcit;



	return 0;

}

EXPORT_SYMBOL_GPL(__rtnl_register);
@@ -277,7 +258,6 @@ int rtnl_unregister(int protocol, int msgtype) 


	rtnl_msg_handlers[protocol][msgindex].doit = NULL;

	rtnl_msg_handlers[protocol][msgindex].dumpit = NULL;

	rtnl_msg_handlers[protocol][msgindex].calcit = NULL;



	return 0;

}
@@ -4187,15 +4167,14 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, 
	if (kind == 2 && nlh->nlmsg_flags&NLM_F_DUMP) {

		struct sock *rtnl;

		rtnl_dumpit_func dumpit;

		rtnl_calcit_func calcit;

		u16 min_dump_alloc = 0;



		dumpit = rtnl_get_dumpit(family, type);

		if (dumpit == NULL)

			return -EOPNOTSUPP;

		calcit = rtnl_get_calcit(family, type);

		if (calcit)

			min_dump_alloc = calcit(skb, nlh);



		if (type == RTM_GETLINK)

			min_dump_alloc = rtnl_calcit(skb, nlh);



		__rtnl_unlock();

		rtnl = net->rtnl;
@@ -4300,7 +4279,7 @@ void __init rtnetlink_init(void) 
	register_netdevice_notifier(&rtnetlink_dev_notifier);



	rtnl_register(PF_UNSPEC, RTM_GETLINK, rtnl_getlink,

		      rtnl_dump_ifinfo, rtnl_calcit);

		      rtnl_dump_ifinfo, NULL);

	rtnl_register(PF_UNSPEC, RTM_SETLINK, rtnl_setlink, NULL, NULL);

	rtnl_register(PF_UNSPEC, RTM_NEWLINK, rtnl_newlink, NULL, NULL);

	rtnl_register(PF_UNSPEC, RTM_DELLINK, rtnl_dellink, NULL, NULL);

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