This is a note to let you know that I've just added the patch titled
ethernet: add a helper for assigning port addresses
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ethernet-add-a-helper-for-assigning-port-addresses.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 3c666f7b3d78de38c4a15b011b91edecb6dfd146
Author: Jakub Kicinski <kuba@xxxxxxxxxx>
Date: Mon Oct 18 14:10:02 2021 -0700
ethernet: add a helper for assigning port addresses
[ Upstream commit e80094a473eefad9d856ce3ab0d7afdbb64800c4 ]
We have 5 drivers which offset base MAC addr by port id.
Create a helper for them.
This helper takes care of overflows, which some drivers
did not do, please complain if that's going to break
anything!
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Reviewed-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
Reviewed-by: Shannon Nelson <snelson@xxxxxxxxxxx>
Reviewed-by: Ido Schimmel <idosch@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Stable-dep-of: 6e159fd653d7 ("ethernet: Add helper for assigning packet type when dest address does not match device address")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h
index 2932a40060c1d..fef4bb77f7590 100644
--- a/include/linux/etherdevice.h
+++ b/include/linux/etherdevice.h
@@ -522,6 +522,27 @@ static inline unsigned long compare_ether_header(const void *a, const void *b)
#endif
}
+/**
+ * eth_hw_addr_gen - Generate and assign Ethernet address to a port
+ * @dev: pointer to port's net_device structure
+ * @base_addr: base Ethernet address
+ * @id: offset to add to the base address
+ *
+ * Generate a MAC address using a base address and an offset and assign it
+ * to a net_device. Commonly used by switch drivers which need to compute
+ * addresses for all their ports. addr_assign_type is not changed.
+ */
+static inline void eth_hw_addr_gen(struct net_device *dev, const u8 *base_addr,
+ unsigned int id)
+{
+ u64 u = ether_addr_to_u64(base_addr);
+ u8 addr[ETH_ALEN];
+
+ u += id;
+ u64_to_ether_addr(u, addr);
+ eth_hw_addr_set(dev, addr);
+}
+
/**
* eth_skb_pad - Pad buffer to mininum number of octets for Ethernet frame
* @skb: Buffer to pad
