From 7390609b0121a1b982c5ecdfcd72dc328e5784ee Mon Sep 17 00:00:00 2001 From: Michael Walle Date: Mon, 6 Feb 2023 13:43:42 +0000 Subject: [PATCH] net: add helper eth_addr_add() Add a helper to add an offset to a ethernet address. This comes in handy if you have a base ethernet address for multiple interfaces. Signed-off-by: Michael Walle Reviewed-by: Andrew Lunn Acked-by: Jakub Kicinski Signed-off-by: Srinivas Kandagatla Link: https://lore.kernel.org/r/20230206134356.839737-9-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman --- include/linux/etherdevice.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h index a541f0c4f146..224645f17c33 100644 --- a/include/linux/etherdevice.h +++ b/include/linux/etherdevice.h @@ -507,6 +507,20 @@ static inline void eth_addr_inc(u8 *addr) u64_to_ether_addr(u, addr); } +/** + * eth_addr_add() - Add (or subtract) an offset to/from the given MAC address. + * + * @offset: Offset to add. + * @addr: Pointer to a six-byte array containing Ethernet address to increment. + */ +static inline void eth_addr_add(u8 *addr, long offset) +{ + u64 u = ether_addr_to_u64(addr); + + u += offset; + u64_to_ether_addr(u, addr); +} + /** * is_etherdev_addr - Tell if given Ethernet address belongs to the device. * @dev: Pointer to a device structure