From c1f79426e2df5ef96fe3e76de6c7606d15bf390b Mon Sep 17 00:00:00 2001 From: Stefan Assmann Date: Thu, 22 Jul 2010 02:50:21 +0000 Subject: sysfs: add attribute to indicate hw address assignment type Add addr_assign_type to struct net_device and expose it via sysfs. This new attribute has the purpose of giving user-space the ability to distinguish between different assignment types of MAC addresses. For example user-space can treat NICs with randomly generated MAC addresses differently than NICs that have permanent (locally assigned) MAC addresses. For the former udev could write a persistent net rule by matching the device path instead of the MAC address. There's also the case of devices that 'steal' MAC addresses from slave devices. In which it is also be beneficial for user-space to be aware of the fact. This patch also introduces a helper function to assist adoption of drivers that generate MAC addresses randomly. Signed-off-by: Stefan Assmann Signed-off-by: David S. Miller --- include/linux/etherdevice.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) (limited to 'include/linux/etherdevice.h') diff --git a/include/linux/etherdevice.h b/include/linux/etherdevice.h index 3d7a6687d247..848480bc2bf9 100644 --- a/include/linux/etherdevice.h +++ b/include/linux/etherdevice.h @@ -126,6 +126,20 @@ static inline void random_ether_addr(u8 *addr) addr [0] |= 0x02; /* set local assignment bit (IEEE802) */ } +/** + * dev_hw_addr_random - Create random MAC and set device flag + * @dev: pointer to net_device structure + * @addr: Pointer to a six-byte array containing the Ethernet address + * + * Generate random MAC to be used by a device and set addr_assign_type + * so the state can be read by sysfs and be used by udev. + */ +static inline void dev_hw_addr_random(struct net_device *dev, u8 *hwaddr) +{ + dev->addr_assign_type |= NET_ADDR_RANDOM; + random_ether_addr(hwaddr); +} + /** * compare_ether_addr - Compare two Ethernet addresses * @addr1: Pointer to a six-byte array containing the Ethernet address -- cgit v1.2.3