[PATCH v4 7/8] net-device: Use new helpers from overflow.h in netdevice APIs

[Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>]

We have two new helpers struct_size_with_data() and struct_data_pointer()
that we can utilize in alloc_netdev_mqs() and netdev_priv(). Do it so.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
 include/linux/netdevice.h |  3 ++-
 net/core/dev.c            | 10 +++++-----
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index c41019f34179..d046dca18854 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -25,6 +25,7 @@
 #include <linux/bug.h>
 #include <linux/delay.h>
 #include <linux/atomic.h>
+#include <linux/overflow.h>
 #include <linux/prefetch.h>
 #include <asm/cache.h>
 #include <asm/byteorder.h>
@@ -2668,7 +2669,7 @@ void dev_net_set(struct net_device *dev, struct net *net)
  */
 static inline void *netdev_priv(const struct net_device *dev)
 {
-	return (char *)dev + ALIGN(sizeof(struct net_device), NETDEV_ALIGN);
+	return struct_data_pointer(dev, NETDEV_ALIGN);
 }
 
 /* Set the sysfs physical device reference for the network logical device
diff --git a/net/core/dev.c b/net/core/dev.c
index 69c3e3613372..80b765bb8ba2 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -10859,12 +10859,12 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
 		return NULL;
 	}
 
-	alloc_size = sizeof(struct net_device);
-	if (sizeof_priv) {
+	if (sizeof_priv)
 		/* ensure 32-byte alignment of private area */
-		alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
-		alloc_size += sizeof_priv;
-	}
+		alloc_size = struct_size_with_data(p, NETDEV_ALIGN, sizeof_priv);
+	else
+		alloc_size = sizeof(struct net_device);
+
 	/* ensure 32-byte alignment of whole construct */
 	alloc_size += NETDEV_ALIGN - 1;
 
-- 
2.43.0.rc1.1.gbec44491f096