net: create netdev->dev_addr assignment helpers

[ Upstream commit 48eab831ae8b9f7002a533fa4235eed63ea1f1a3 ]

Recent work on converting address list to a tree made it obvious
we need an abstraction around writing netdev->dev_addr. Without
such abstraction updating the main device address is invisible
to the core.

Introduce a number of helpers which for now just wrap memcpy()
but in the future can make necessary changes to the address
tree.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stable-dep-of: 391af06a02e7 ("wifi: wl3501_cs: Fix an error handling path in wl3501_probe()")
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit c368c4defa94ed6c5db9059e4667220b257be5b9)
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h
index 0913690..e645433 100644
--- a/include/linux/etherdevice.h
+++ b/include/linux/etherdevice.h
@@ -292,6 +292,18 @@
 }
 
 /**
+ * eth_hw_addr_set - Assign Ethernet address to a net_device
+ * @dev: pointer to net_device structure
+ * @addr: address to assign
+ *
+ * Assign given address to the net_device, addr_assign_type is not changed.
+ */
+static inline void eth_hw_addr_set(struct net_device *dev, const u8 *addr)
+{
+	ether_addr_copy(dev->dev_addr, addr);
+}
+
+/**
  * eth_hw_addr_inherit - Copy dev_addr from another net_device
  * @dst: pointer to net_device to copy dev_addr to
  * @src: pointer to net_device to copy dev_addr from
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index bdde6d1..c10b2ed 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -3791,6 +3791,24 @@
 void __hw_addr_init(struct netdev_hw_addr_list *list);
 
 /* Functions used for device addresses handling */
+static inline void
+__dev_addr_set(struct net_device *dev, const u8 *addr, size_t len)
+{
+	memcpy(dev->dev_addr, addr, len);
+}
+
+static inline void dev_addr_set(struct net_device *dev, const u8 *addr)
+{
+	__dev_addr_set(dev, addr, dev->addr_len);
+}
+
+static inline void
+dev_addr_mod(struct net_device *dev, unsigned int offset,
+	     const u8 *addr, size_t len)
+{
+	memcpy(&dev->dev_addr[offset], addr, len);
+}
+
 int dev_addr_add(struct net_device *dev, const unsigned char *addr,
 		 unsigned char addr_type);
 int dev_addr_del(struct net_device *dev, const unsigned char *addr,