Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

Conflicts:
	drivers/net/usb/qmi_wwan.c

Overlapping additions of new device IDs to qmi_wwan.c

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 55 insertions, 24 deletions

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 6c0fe4c7ce8d..e476f01add87 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -321,8 +321,7 @@ static const struct rt6_info ip6_blk_hole_entry_template = {
 /* allocate dst with ip6_dst_ops */
 static struct rt6_info *__ip6_dst_alloc(struct net *net,
                                         struct net_device *dev,
-                                        int flags,
-                                        struct fib6_table *table)
+                                        int flags)
 {
         struct rt6_info *rt = dst_alloc(&net->ipv6.ip6_dst_ops, dev,
                                         0, DST_OBSOLETE_FORCE_CHK, flags);
@@ -339,10 +338,9 @@ static struct rt6_info *__ip6_dst_alloc(struct net *net,
 
 static struct rt6_info *ip6_dst_alloc(struct net *net,
                                       struct net_device *dev,
-                                      int flags,
-                                      struct fib6_table *table)
+                                      int flags)
 {
-        struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags, table);
+        struct rt6_info *rt = __ip6_dst_alloc(net, dev, flags);
 
         if (rt) {
                 rt->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, GFP_ATOMIC);
@@ -959,8 +957,7 @@ static struct rt6_info *ip6_rt_cache_alloc(struct rt6_info *ort,
         if (ort->rt6i_flags & (RTF_CACHE | RTF_PCPU))
                 ort = (struct rt6_info *)ort->dst.from;
 
-        rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev,
-                             0, ort->rt6i_table);
+        rt = __ip6_dst_alloc(dev_net(ort->dst.dev), ort->dst.dev, 0);
 
         if (!rt)
                 return NULL;
@@ -992,8 +989,7 @@ static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
         struct rt6_info *pcpu_rt;
 
         pcpu_rt = __ip6_dst_alloc(dev_net(rt->dst.dev),
-                                  rt->dst.dev, rt->dst.flags,
-                                  rt->rt6i_table);
+                                  rt->dst.dev, rt->dst.flags);
 
         if (!pcpu_rt)
                 return NULL;
@@ -1006,32 +1002,53 @@ static struct rt6_info *ip6_rt_pcpu_alloc(struct rt6_info *rt)
 /* It should be called with read_lock_bh(&tb6_lock) acquired */
 static struct rt6_info *rt6_get_pcpu_route(struct rt6_info *rt)
 {
-        struct rt6_info *pcpu_rt, *prev, **p;
+        struct rt6_info *pcpu_rt, **p;
 
         p = this_cpu_ptr(rt->rt6i_pcpu);
         pcpu_rt = *p;
 
-        if (pcpu_rt)
-                goto done;
+        if (pcpu_rt) {
+                dst_hold(&pcpu_rt->dst);
+                rt6_dst_from_metrics_check(pcpu_rt);
+        }
+        return pcpu_rt;
+}
+
+static struct rt6_info *rt6_make_pcpu_route(struct rt6_info *rt)
+{
+        struct fib6_table *table = rt->rt6i_table;
+        struct rt6_info *pcpu_rt, *prev, **p;
 
         pcpu_rt = ip6_rt_pcpu_alloc(rt);
         if (!pcpu_rt) {
                 struct net *net = dev_net(rt->dst.dev);
 
-                pcpu_rt = net->ipv6.ip6_null_entry;
-                goto done;
+                dst_hold(&net->ipv6.ip6_null_entry->dst);
+                return net->ipv6.ip6_null_entry;
         }
 
-        prev = cmpxchg(p, NULL, pcpu_rt);
-        if (prev) {
-                /* If someone did it before us, return prev instead */
+        read_lock_bh(&table->tb6_lock);
+        if (rt->rt6i_pcpu) {
+                p = this_cpu_ptr(rt->rt6i_pcpu);
+                prev = cmpxchg(p, NULL, pcpu_rt);
+                if (prev) {
+                        /* If someone did it before us, return prev instead */
+                        dst_destroy(&pcpu_rt->dst);
+                        pcpu_rt = prev;
+                }
+        } else {
+                /* rt has been removed from the fib6 tree
+                 * before we have a chance to acquire the read_lock.
+                 * In this case, don't brother to create a pcpu rt
+                 * since rt is going away anyway.  The next
+                 * dst_check() will trigger a re-lookup.
+                 */
                 dst_destroy(&pcpu_rt->dst);
-                pcpu_rt = prev;
+                pcpu_rt = rt;
         }
-
-done:
         dst_hold(&pcpu_rt->dst);
         rt6_dst_from_metrics_check(pcpu_rt);
+        read_unlock_bh(&table->tb6_lock);
         return pcpu_rt;
 }
 
@@ -1106,9 +1123,22 @@ redo_rt6_select:
                 rt->dst.lastuse = jiffies;
                 rt->dst.__use++;
                 pcpu_rt = rt6_get_pcpu_route(rt);
-                read_unlock_bh(&table->tb6_lock);
+
+                if (pcpu_rt) {
+                        read_unlock_bh(&table->tb6_lock);
+                } else {
+                        /* We have to do the read_unlock first
+                         * because rt6_make_pcpu_route() may trigger
+                         * ip6_dst_gc() which will take the write_lock.
+                         */
+                        dst_hold(&rt->dst);
+                        read_unlock_bh(&table->tb6_lock);
+                        pcpu_rt = rt6_make_pcpu_route(rt);
+                        dst_release(&rt->dst);
+                }
 
                 return pcpu_rt;
+
         }
 }
 
@@ -1569,7 +1599,7 @@ struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
         if (unlikely(!idev))
                 return ERR_PTR(-ENODEV);
 
-        rt = ip6_dst_alloc(net, dev, 0, NULL);
+        rt = ip6_dst_alloc(net, dev, 0);
         if (unlikely(!rt)) {
                 in6_dev_put(idev);
                 dst = ERR_PTR(-ENOMEM);
@@ -1756,7 +1786,8 @@ int ip6_route_add(struct fib6_config *cfg)
         if (!table)
                 goto out;
 
-        rt = ip6_dst_alloc(net, NULL, (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT, table);
+        rt = ip6_dst_alloc(net, NULL,
+                           (cfg->fc_flags & RTF_ADDRCONF) ? 0 : DST_NOCOUNT);
 
         if (!rt) {
                 err = -ENOMEM;
@@ -2432,7 +2463,7 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
 {
         struct net *net = dev_net(idev->dev);
         struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
-                                            DST_NOCOUNT, NULL);
+                                            DST_NOCOUNT);
         if (!rt)
                 return ERR_PTR(-ENOMEM);