commit c0ed1c14a72ca9ebacd51fb94a8aca488b0d361e
author Steffen Klassert <steffen.klassert@secunet.com> Wed Dec 21 16:48:08 2011 -0500
committer David S. Miller <davem@davemloft.net> Wed Dec 21 16:48:08 2011 -0500
tree e689f7fd62e7633b9b254f9a456b65a1150c6e23
parent 9f28a2fc0bd77511f649c0a788c7bf9a5fd04edb

net: Add a flow_cache_flush_deferred function

flow_cach_flush() might sleep but can be called from
atomic context via the xfrm garbage collector. So add
a flow_cache_flush_deferred() function and use this if
the xfrm garbage colector is invoked from within the
packet path.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Timo Teräs <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/xfrm/xfrm_policy.c

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 2118d64..9049a5c 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -2276,8 +2276,6 @@
 {
 	struct dst_entry *head, *next;
 
-	flow_cache_flush();
-
 	spin_lock_bh(&xfrm_policy_sk_bundle_lock);
 	head = xfrm_policy_sk_bundles;
 	xfrm_policy_sk_bundles = NULL;
@@ -2290,6 +2288,18 @@
 	}
 }
 
+static void xfrm_garbage_collect(struct net *net)
+{
+	flow_cache_flush();
+	__xfrm_garbage_collect(net);
+}
+
+static void xfrm_garbage_collect_deferred(struct net *net)
+{
+	flow_cache_flush_deferred();
+	__xfrm_garbage_collect(net);
+}
+
 static void xfrm_init_pmtu(struct dst_entry *dst)
 {
 	do {
@@ -2422,7 +2432,7 @@
 		if (likely(dst_ops->neigh_lookup == NULL))
 			dst_ops->neigh_lookup = xfrm_neigh_lookup;
 		if (likely(afinfo->garbage_collect == NULL))
-			afinfo->garbage_collect = __xfrm_garbage_collect;
+			afinfo->garbage_collect = xfrm_garbage_collect_deferred;
 		xfrm_policy_afinfo[afinfo->family] = afinfo;
 	}
 	write_unlock_bh(&xfrm_policy_afinfo_lock);
@@ -2516,7 +2526,7 @@
 
 	switch (event) {
 	case NETDEV_DOWN:
-		__xfrm_garbage_collect(dev_net(dev));
+		xfrm_garbage_collect(dev_net(dev));
 	}
 	return NOTIFY_DONE;
 }