percpu: add __percpu sparse annotations to net drivers

Add __percpu sparse annotations to net drivers.

These annotations are to make sparse consider percpu variables to be
in a different address space and warn if accessed without going
through percpu accessors.  This patch doesn't affect normal builds.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 7 deletions

diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c
index b9fcc9819837..72b7949c91b1 100644
--- a/drivers/net/loopback.c
+++ b/drivers/net/loopback.c
@@ -72,7 +72,8 @@ struct pcpu_lstats {
 static netdev_tx_t loopback_xmit(struct sk_buff *skb,
                                  struct net_device *dev)
 {
-        struct pcpu_lstats *pcpu_lstats, *lb_stats;
+        struct pcpu_lstats __percpu *pcpu_lstats;
+        struct pcpu_lstats *lb_stats;
         int len;
 
         skb_orphan(skb);
@@ -80,7 +81,7 @@ static netdev_tx_t loopback_xmit(struct sk_buff *skb,
         skb->protocol = eth_type_trans(skb, dev);
 
         /* it's OK to use per_cpu_ptr() because BHs are off */
-        pcpu_lstats = dev->ml_priv;
+        pcpu_lstats = (void __percpu __force *)dev->ml_priv;
         lb_stats = this_cpu_ptr(pcpu_lstats);
 
         len = skb->len;
@@ -95,14 +96,14 @@ static netdev_tx_t loopback_xmit(struct sk_buff *skb,
 
 static struct net_device_stats *loopback_get_stats(struct net_device *dev)
 {
-        const struct pcpu_lstats *pcpu_lstats;
+        const struct pcpu_lstats __percpu *pcpu_lstats;
         struct net_device_stats *stats = &dev->stats;
         unsigned long bytes = 0;
         unsigned long packets = 0;
         unsigned long drops = 0;
         int i;
 
-        pcpu_lstats = dev->ml_priv;
+        pcpu_lstats = (void __percpu __force *)dev->ml_priv;
         for_each_possible_cpu(i) {
                 const struct pcpu_lstats *lb_stats;
 
@@ -135,19 +136,20 @@ static const struct ethtool_ops loopback_ethtool_ops = {
 
 static int loopback_dev_init(struct net_device *dev)
 {
-        struct pcpu_lstats *lstats;
+        struct pcpu_lstats __percpu *lstats;
 
         lstats = alloc_percpu(struct pcpu_lstats);
         if (!lstats)
                 return -ENOMEM;
 
-        dev->ml_priv = lstats;
+        dev->ml_priv = (void __force *)lstats;
         return 0;
 }
 
 static void loopback_dev_free(struct net_device *dev)
 {
-        struct pcpu_lstats *lstats = dev->ml_priv;
+        struct pcpu_lstats __percpu *lstats =
+                (void __percpu __force *)dev->ml_priv;
 
         free_percpu(lstats);
         free_netdev(dev);