ipv4: ipmr: remove net pointer from struct mfc_cache

Now that cache entries in unres_queue don't need to be distinguished by their
network namespace pointer anymore, we can remove it from struct mfc_cache
add pass the namespace as function argument to the functions that need it.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/mroute.h b/include/linux/mroute.h
index c5f3d53..de7780a 100644
--- a/include/linux/mroute.h
+++ b/include/linux/mroute.h
@@ -192,9 +192,6 @@
 
 struct mfc_cache {
 	struct mfc_cache *next;			/* Next entry on cache line 	*/
-#ifdef CONFIG_NET_NS
-	struct net *mfc_net;
-#endif
 	__be32 mfc_mcastgrp;			/* Group the entry belongs to 	*/
 	__be32 mfc_origin;			/* Source of packet 		*/
 	vifi_t mfc_parent;			/* Source interface		*/
@@ -217,18 +214,6 @@
 	} mfc_un;
 };
 
-static inline
-struct net *mfc_net(const struct mfc_cache *mfc)
-{
-	return read_pnet(&mfc->mfc_net);
-}
-
-static inline
-void mfc_net_set(struct mfc_cache *mfc, struct net *net)
-{
-	write_pnet(&mfc->mfc_net, hold_net(net));
-}
-
 #define MFC_STATIC		1
 #define MFC_NOTIFY		2
 
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index d6aa65e..f8e25c8 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -93,10 +93,12 @@
 
 static struct kmem_cache *mrt_cachep __read_mostly;
 
-static int ip_mr_forward(struct sk_buff *skb, struct mfc_cache *cache, int local);
+static int ip_mr_forward(struct net *net, struct sk_buff *skb,
+			 struct mfc_cache *cache, int local);
 static int ipmr_cache_report(struct net *net,
 			     struct sk_buff *pkt, vifi_t vifi, int assert);
-static int ipmr_fill_mroute(struct sk_buff *skb, struct mfc_cache *c, struct rtmsg *rtm);
+static int ipmr_fill_mroute(struct net *net, struct sk_buff *skb,
+			    struct mfc_cache *c, struct rtmsg *rtm);
 
 /* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */
 
@@ -325,7 +327,6 @@
 
 static inline void ipmr_cache_free(struct mfc_cache *c)
 {
-	release_net(mfc_net(c));
 	kmem_cache_free(mrt_cachep, c);
 }
 
@@ -333,11 +334,10 @@
    and reporting error to netlink readers.
  */
 
-static void ipmr_destroy_unres(struct mfc_cache *c)
+static void ipmr_destroy_unres(struct net *net, struct mfc_cache *c)
 {
 	struct sk_buff *skb;
 	struct nlmsgerr *e;
-	struct net *net = mfc_net(c);
 
 	atomic_dec(&net->ipv4.cache_resolve_queue_len);
 
@@ -392,7 +392,7 @@
 
 		*cp = c->next;
 
-		ipmr_destroy_unres(c);
+		ipmr_destroy_unres(net, c);
 	}
 
 	if (net->ipv4.mfc_unres_queue != NULL)
@@ -404,10 +404,10 @@
 
 /* Fill oifs list. It is called under write locked mrt_lock. */
 
-static void ipmr_update_thresholds(struct mfc_cache *cache, unsigned char *ttls)
+static void ipmr_update_thresholds(struct net *net, struct mfc_cache *cache,
+				   unsigned char *ttls)
 {
 	int vifi;
-	struct net *net = mfc_net(cache);
 
 	cache->mfc_un.res.minvif = MAXVIFS;
 	cache->mfc_un.res.maxvif = 0;
@@ -547,24 +547,22 @@
 /*
  *	Allocate a multicast cache entry
  */
-static struct mfc_cache *ipmr_cache_alloc(struct net *net)
+static struct mfc_cache *ipmr_cache_alloc(void)
 {
 	struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_KERNEL);
 	if (c == NULL)
 		return NULL;
 	c->mfc_un.res.minvif = MAXVIFS;
-	mfc_net_set(c, net);
 	return c;
 }
 
-static struct mfc_cache *ipmr_cache_alloc_unres(struct net *net)
+static struct mfc_cache *ipmr_cache_alloc_unres(void)
 {
 	struct mfc_cache *c = kmem_cache_zalloc(mrt_cachep, GFP_ATOMIC);
 	if (c == NULL)
 		return NULL;
 	skb_queue_head_init(&c->mfc_un.unres.unresolved);
 	c->mfc_un.unres.expires = jiffies + 10*HZ;
-	mfc_net_set(c, net);
 	return c;
 }
 
@@ -572,7 +570,8 @@
  *	A cache entry has gone into a resolved state from queued
  */
 
-static void ipmr_cache_resolve(struct mfc_cache *uc, struct mfc_cache *c)
+static void ipmr_cache_resolve(struct net *net, struct mfc_cache *uc,
+			       struct mfc_cache *c)
 {
 	struct sk_buff *skb;
 	struct nlmsgerr *e;
@@ -585,7 +584,7 @@
 		if (ip_hdr(skb)->version == 0) {
 			struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr));
 
-			if (ipmr_fill_mroute(skb, c, NLMSG_DATA(nlh)) > 0) {
+			if (ipmr_fill_mroute(net, skb, c, NLMSG_DATA(nlh)) > 0) {
 				nlh->nlmsg_len = (skb_tail_pointer(skb) -
 						  (u8 *)nlh);
 			} else {
@@ -597,9 +596,9 @@
 				memset(&e->msg, 0, sizeof(e->msg));
 			}
 
-			rtnl_unicast(skb, mfc_net(c), NETLINK_CB(skb).pid);
+			rtnl_unicast(skb, net, NETLINK_CB(skb).pid);
 		} else
-			ip_mr_forward(skb, c, 0);
+			ip_mr_forward(net, skb, c, 0);
 	}
 }
 
@@ -717,7 +716,7 @@
 		 */
 
 		if (atomic_read(&net->ipv4.cache_resolve_queue_len) >= 10 ||
-		    (c = ipmr_cache_alloc_unres(net)) == NULL) {
+		    (c = ipmr_cache_alloc_unres()) == NULL) {
 			spin_unlock_bh(&mfc_unres_lock);
 
 			kfree_skb(skb);
@@ -814,7 +813,7 @@
 	if (c != NULL) {
 		write_lock_bh(&mrt_lock);
 		c->mfc_parent = mfc->mfcc_parent;
-		ipmr_update_thresholds(c, mfc->mfcc_ttls);
+		ipmr_update_thresholds(net, c, mfc->mfcc_ttls);
 		if (!mrtsock)
 			c->mfc_flags |= MFC_STATIC;
 		write_unlock_bh(&mrt_lock);
@@ -824,14 +823,14 @@
 	if (!ipv4_is_multicast(mfc->mfcc_mcastgrp.s_addr))
 		return -EINVAL;
 
-	c = ipmr_cache_alloc(net);
+	c = ipmr_cache_alloc();
 	if (c == NULL)
 		return -ENOMEM;
 
 	c->mfc_origin = mfc->mfcc_origin.s_addr;
 	c->mfc_mcastgrp = mfc->mfcc_mcastgrp.s_addr;
 	c->mfc_parent = mfc->mfcc_parent;
-	ipmr_update_thresholds(c, mfc->mfcc_ttls);
+	ipmr_update_thresholds(net, c, mfc->mfcc_ttls);
 	if (!mrtsock)
 		c->mfc_flags |= MFC_STATIC;
 
@@ -859,7 +858,7 @@
 	spin_unlock_bh(&mfc_unres_lock);
 
 	if (uc) {
-		ipmr_cache_resolve(uc, c);
+		ipmr_cache_resolve(net, uc, c);
 		ipmr_cache_free(uc);
 	}
 	return 0;
@@ -910,7 +909,7 @@
 		cp = &net->ipv4.mfc_unres_queue;
 		while ((c = *cp) != NULL) {
 			*cp = c->next;
-			ipmr_destroy_unres(c);
+			ipmr_destroy_unres(net, c);
 		}
 		spin_unlock_bh(&mfc_unres_lock);
 	}
@@ -1221,9 +1220,9 @@
  *	Processing handlers for ipmr_forward
  */
 
-static void ipmr_queue_xmit(struct sk_buff *skb, struct mfc_cache *c, int vifi)
+static void ipmr_queue_xmit(struct net *net, struct sk_buff *skb,
+			    struct mfc_cache *c, int vifi)
 {
-	struct net *net = mfc_net(c);
 	const struct iphdr *iph = ip_hdr(skb);
 	struct vif_device *vif = &net->ipv4.vif_table[vifi];
 	struct net_device *dev;
@@ -1335,11 +1334,11 @@
 
 /* "local" means that we should preserve one skb (for local delivery) */
 
-static int ip_mr_forward(struct sk_buff *skb, struct mfc_cache *cache, int local)
+static int ip_mr_forward(struct net *net, struct sk_buff *skb,
+			 struct mfc_cache *cache, int local)
 {
 	int psend = -1;
 	int vif, ct;
-	struct net *net = mfc_net(cache);
 
 	vif = cache->mfc_parent;
 	cache->mfc_un.res.pkt++;
@@ -1396,7 +1395,7 @@
 			if (psend != -1) {
 				struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
 				if (skb2)
-					ipmr_queue_xmit(skb2, cache, psend);
+					ipmr_queue_xmit(net, skb2, cache, psend);
 			}
 			psend = ct;
 		}
@@ -1405,9 +1404,9 @@
 		if (local) {
 			struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
 			if (skb2)
-				ipmr_queue_xmit(skb2, cache, psend);
+				ipmr_queue_xmit(net, skb2, cache, psend);
 		} else {
-			ipmr_queue_xmit(skb, cache, psend);
+			ipmr_queue_xmit(net, skb, cache, psend);
 			return 0;
 		}
 	}
@@ -1488,7 +1487,7 @@
 		return -ENODEV;
 	}
 
-	ip_mr_forward(skb, cache, local);
+	ip_mr_forward(net, skb, cache, local);
 
 	read_unlock(&mrt_lock);
 
@@ -1602,11 +1601,11 @@
 #endif
 
 static int
-ipmr_fill_mroute(struct sk_buff *skb, struct mfc_cache *c, struct rtmsg *rtm)
+ipmr_fill_mroute(struct net *net, struct sk_buff *skb, struct mfc_cache *c,
+		 struct rtmsg *rtm)
 {
 	int ct;
 	struct rtnexthop *nhp;
-	struct net *net = mfc_net(c);
 	u8 *b = skb_tail_pointer(skb);
 	struct rtattr *mp_head;
 
@@ -1686,7 +1685,7 @@
 
 	if (!nowait && (rtm->rtm_flags&RTM_F_NOTIFY))
 		cache->mfc_flags |= MFC_NOTIFY;
-	err = ipmr_fill_mroute(skb, cache, rtm);
+	err = ipmr_fill_mroute(net, skb, cache, rtm);
 	read_unlock(&mrt_lock);
 	return err;
 }