Commit 4045e57c authored by Benjamin Thery's avatar Benjamin Thery Committed by David S. Miller
Browse files

netns: ip6mr: declare counter cache_resolve_queue_len per-namespace 



Preliminary work to make IPv6 multicast forwarding netns-aware.

Declare variable cache_resolve_queue_len per-namespace: moves it into
struct netns_ipv6.

This variable counts the number of unresolved cache entries queued in the
list mfc_unres_queue. This list is kept global to all netns as the number
of entries per namespace is limited to 10 (hardcoded in routine 
ip6mr_cache_unresolved).
Entries belonging to different namespaces in mfc_unres_queue will be
identified by matching the mfc_net member introduced previously in 
struct mfc6_cache.

Keeping this list global to all netns, also allows us to keep a single
timer (ipmr_expire_timer) to handle their expiration.
In some places cache_resolve_queue_len value was tested for arming 
or deleting the timer. These tests were equivalent to testing 
mfc_unres_queue value instead and are replaced in this patch.

At the moment, cache_resolve_queue_len is only referenced in init_net.

Signed-off-by: default avatarBenjamin Thery <benjamin.thery@bull.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 4a6258a0

include/net/netns/ipv6.h

+1 −0
Original line number Diff line number Diff line
@@ -60,6 +60,7 @@ struct netns_ipv6 { 
	struct mfc6_cache	**mfc6_cache_array;

	struct mif_device	*vif6_table;

	int			maxvif;

	atomic_t		cache_resolve_queue_len;

#endif

};

#endif

net/ipv6/ip6mr.c

+21 −19
Original line number Diff line number Diff line
@@ -69,7 +69,6 @@ static int mroute_do_pim; 
#endif



static struct mfc6_cache *mfc_unres_queue;		/* Queue of unresolved entries */

static atomic_t cache_resolve_queue_len;		/* Size of unresolved	*/



/* Special spinlock for queue of unresolved entries */

static DEFINE_SPINLOCK(mfc_unres_lock);
@@ -519,7 +518,7 @@ static void ip6mr_destroy_unres(struct mfc6_cache *c) 
{

	struct sk_buff *skb;



	atomic_dec(&cache_resolve_queue_len);

	atomic_dec(&init_net.ipv6.cache_resolve_queue_len);



	while((skb = skb_dequeue(&c->mfc_un.unres.unresolved)) != NULL) {

		if (ipv6_hdr(skb)->version == 0) {
@@ -561,7 +560,7 @@ static void ipmr_do_expire_process(unsigned long dummy) 
		ip6mr_destroy_unres(c);

	}



	if (atomic_read(&cache_resolve_queue_len))

	if (mfc_unres_queue != NULL)

		mod_timer(&ipmr_expire_timer, jiffies + expires);

}
@@ -572,7 +571,7 @@ static void ipmr_expire_process(unsigned long dummy) 
		return;

	}



	if (atomic_read(&cache_resolve_queue_len))

	if (mfc_unres_queue != NULL)

		ipmr_do_expire_process(dummy);



	spin_unlock(&mfc_unres_lock);
@@ -852,7 +851,8 @@ ip6mr_cache_unresolved(mifi_t mifi, struct sk_buff *skb) 


	spin_lock_bh(&mfc_unres_lock);

	for (c = mfc_unres_queue; c; c = c->next) {

		if (ipv6_addr_equal(&c->mf6c_mcastgrp, &ipv6_hdr(skb)->daddr) &&

		if (net_eq(mfc6_net(c), &init_net) &&

		    ipv6_addr_equal(&c->mf6c_mcastgrp, &ipv6_hdr(skb)->daddr) &&

		    ipv6_addr_equal(&c->mf6c_origin, &ipv6_hdr(skb)->saddr))

			break;

	}
@@ -862,7 +862,7 @@ ip6mr_cache_unresolved(mifi_t mifi, struct sk_buff *skb) 
		 *	Create a new entry if allowable

		 */



		if (atomic_read(&cache_resolve_queue_len) >= 10 ||

		if (atomic_read(&init_net.ipv6.cache_resolve_queue_len) >= 10 ||

		    (c = ip6mr_cache_alloc_unres(&init_net)) == NULL) {

			spin_unlock_bh(&mfc_unres_lock);
@@ -891,7 +891,7 @@ ip6mr_cache_unresolved(mifi_t mifi, struct sk_buff *skb) 
			return err;

		}



		atomic_inc(&cache_resolve_queue_len);

		atomic_inc(&init_net.ipv6.cache_resolve_queue_len);

		c->next = mfc_unres_queue;

		mfc_unres_queue = c;
@@ -1119,14 +1119,16 @@ static int ip6mr_mfc_add(struct mf6cctl *mfc, int mrtsock) 
	spin_lock_bh(&mfc_unres_lock);

	for (cp = &mfc_unres_queue; (uc = *cp) != NULL;

	     cp = &uc->next) {

		if (ipv6_addr_equal(&uc->mf6c_origin, &c->mf6c_origin) &&

		if (net_eq(mfc6_net(uc), &init_net) &&

		    ipv6_addr_equal(&uc->mf6c_origin, &c->mf6c_origin) &&

		    ipv6_addr_equal(&uc->mf6c_mcastgrp, &c->mf6c_mcastgrp)) {

			*cp = uc->next;

			if (atomic_dec_and_test(&cache_resolve_queue_len))

				del_timer(&ipmr_expire_timer);

			atomic_dec(&init_net.ipv6.cache_resolve_queue_len);

			break;

		}

	}

	if (mfc_unres_queue == NULL)

		del_timer(&ipmr_expire_timer);

	spin_unlock_bh(&mfc_unres_lock);



	if (uc) {
@@ -1172,18 +1174,18 @@ static void mroute_clean_tables(struct sock *sk) 
		}

	}



	if (atomic_read(&cache_resolve_queue_len) != 0) {

		struct mfc6_cache *c;

	if (atomic_read(&init_net.ipv6.cache_resolve_queue_len) != 0) {

		struct mfc6_cache *c, **cp;



		spin_lock_bh(&mfc_unres_lock);

		while (mfc_unres_queue != NULL) {

			c = mfc_unres_queue;

			mfc_unres_queue = c->next;

			spin_unlock_bh(&mfc_unres_lock);



		cp = &mfc_unres_queue;

		while ((c = *cp) != NULL) {

			if (!net_eq(mfc6_net(c), &init_net)) {

				cp = &c->next;

				continue;

			}

			*cp = c->next;

			ip6mr_destroy_unres(c);



			spin_lock_bh(&mfc_unres_lock);

		}

		spin_unlock_bh(&mfc_unres_lock);

	}

CRA Git | Maintained and supported by SUSTech CRA and CCSE