Commit b00055aa authored by Stefan Rompf's avatar Stefan Rompf Committed by David S. Miller
Browse files

[NET] core: add RFC2863 operstate 



this patch adds a dormant flag to network devices, RFC2863 operstate derived
from these flags and possibility for userspace interaction. It allows drivers
to signal that a device is unusable for user traffic without disabling
queueing (and therefore the possibility for protocol establishment traffic to
flow) and a userspace supplicant (WPA, 802.1X) to mark a device unusable
without changes to the driver.

It is the result of our long discussion. However I must admit that it
represents what Jamal and I agreed on with compromises towards Krzysztof, but
Thomas and Krzysztof still disagree with some parts. Anyway I think it should
be applied.

Signed-off-by: default avatarStefan Rompf <stefan@loplof.de>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e843b9e1

include/linux/if.h

+23 −3
Original line number Diff line number Diff line
@@ -33,7 +33,7 @@ 
#define	IFF_LOOPBACK	0x8		/* is a loopback net		*/

#define	IFF_POINTOPOINT	0x10		/* interface is has p-p link	*/

#define	IFF_NOTRAILERS	0x20		/* avoid use of trailers	*/

#define	IFF_RUNNING	0x40		/* interface running and carrier ok */

#define	IFF_RUNNING	0x40		/* interface RFC2863 OPER_UP	*/

#define	IFF_NOARP	0x80		/* no ARP protocol		*/

#define	IFF_PROMISC	0x100		/* receive all packets		*/

#define	IFF_ALLMULTI	0x200		/* receive all multicast packets*/
@@ -43,12 +43,16 @@ 


#define IFF_MULTICAST	0x1000		/* Supports multicast		*/



#define IFF_VOLATILE	(IFF_LOOPBACK|IFF_POINTOPOINT|IFF_BROADCAST|IFF_MASTER|IFF_SLAVE|IFF_RUNNING)



#define IFF_PORTSEL	0x2000          /* can set media type		*/

#define IFF_AUTOMEDIA	0x4000		/* auto media select active	*/

#define IFF_DYNAMIC	0x8000		/* dialup device with changing addresses*/



#define IFF_LOWER_UP	0x10000		/* driver signals L1 up		*/

#define IFF_DORMANT	0x20000		/* driver signals dormant	*/



#define IFF_VOLATILE	(IFF_LOOPBACK|IFF_POINTOPOINT|IFF_BROADCAST|\

		IFF_MASTER|IFF_SLAVE|IFF_RUNNING|IFF_LOWER_UP|IFF_DORMANT)



/* Private (from user) interface flags (netdevice->priv_flags). */

#define IFF_802_1Q_VLAN 0x1             /* 802.1Q VLAN device.          */

#define IFF_EBRIDGE	0x2		/* Ethernet bridging device.	*/
@@ -83,6 +87,22 @@ 
#define IF_PROTO_FR_ETH_PVC 0x200B

#define IF_PROTO_RAW    0x200C          /* RAW Socket                   */



/* RFC 2863 operational status */

enum {

	IF_OPER_UNKNOWN,

	IF_OPER_NOTPRESENT,

	IF_OPER_DOWN,

	IF_OPER_LOWERLAYERDOWN,

	IF_OPER_TESTING,

	IF_OPER_DORMANT,

	IF_OPER_UP,

};



/* link modes */

enum {

	IF_LINK_MODE_DEFAULT,

	IF_LINK_MODE_DORMANT,	/* limit upward transition to dormant */

};



/*

 *	Device mapping structure. I'd just gone off and designed a

include/linux/netdevice.h

+33 −2
Original line number Diff line number Diff line
@@ -230,7 +230,8 @@ enum netdev_state_t 
	__LINK_STATE_SCHED,

	__LINK_STATE_NOCARRIER,

	__LINK_STATE_RX_SCHED,

	__LINK_STATE_LINKWATCH_PENDING

	__LINK_STATE_LINKWATCH_PENDING,

	__LINK_STATE_DORMANT,

};
@@ -335,11 +336,14 @@ struct net_device 
	 */





	unsigned short		flags;	/* interface flags (a la BSD)	*/

	unsigned int		flags;	/* interface flags (a la BSD)	*/

	unsigned short		gflags;

        unsigned short          priv_flags; /* Like 'flags' but invisible to userspace. */

	unsigned short		padded;	/* How much padding added by alloc_netdev() */



	unsigned char		operstate; /* RFC2863 operstate */

	unsigned char		link_mode; /* mapping policy to operstate */



	unsigned		mtu;	/* interface MTU value		*/

	unsigned short		type;	/* interface hardware type	*/

	unsigned short		hard_header_len;	/* hardware hdr length	*/
@@ -714,6 +718,10 @@ static inline void dev_put(struct net_device *dev) 
/* Carrier loss detection, dial on demand. The functions netif_carrier_on

 * and _off may be called from IRQ context, but it is caller

 * who is responsible for serialization of these calls.

 *

 * The name carrier is inappropriate, these functions should really be

 * called netif_lowerlayer_*() because they represent the state of any

 * kind of lower layer not just hardware media.

 */



extern void linkwatch_fire_event(struct net_device *dev);
@@ -729,6 +737,29 @@ extern void netif_carrier_on(struct net_device *dev); 


extern void netif_carrier_off(struct net_device *dev);



static inline void netif_dormant_on(struct net_device *dev)

{

	if (!test_and_set_bit(__LINK_STATE_DORMANT, &dev->state))

		linkwatch_fire_event(dev);

}



static inline void netif_dormant_off(struct net_device *dev)

{

	if (test_and_clear_bit(__LINK_STATE_DORMANT, &dev->state))

		linkwatch_fire_event(dev);

}



static inline int netif_dormant(const struct net_device *dev)

{

	return test_bit(__LINK_STATE_DORMANT, &dev->state);

}





static inline int netif_oper_up(const struct net_device *dev) {

	return (dev->operstate == IF_OPER_UP ||

		dev->operstate == IF_OPER_UNKNOWN /* backward compat */);

}



/* Hot-plugging. */

static inline int netif_device_present(struct net_device *dev)

{

include/linux/rtnetlink.h

+2 −0
Original line number Diff line number Diff line
@@ -733,6 +733,8 @@ enum 
#define IFLA_MAP IFLA_MAP

	IFLA_WEIGHT,

#define IFLA_WEIGHT IFLA_WEIGHT

	IFLA_OPERSTATE,

	IFLA_LINKMODE,

	__IFLA_MAX

};

net/core/dev.c

+11 −3
Original line number Diff line number Diff line
@@ -2174,12 +2174,20 @@ unsigned dev_get_flags(const struct net_device *dev) 


	flags = (dev->flags & ~(IFF_PROMISC |

				IFF_ALLMULTI |

				IFF_RUNNING)) | 

				IFF_RUNNING |

				IFF_LOWER_UP |

				IFF_DORMANT)) |

		(dev->gflags & (IFF_PROMISC |

				IFF_ALLMULTI));



	if (netif_running(dev) && netif_carrier_ok(dev))

	if (netif_running(dev)) {

		if (netif_oper_up(dev))

			flags |= IFF_RUNNING;

		if (netif_carrier_ok(dev))

			flags |= IFF_LOWER_UP;

		if (netif_dormant(dev))

			flags |= IFF_DORMANT;

	}



	return flags;

}

net/core/link_watch.c

+40 −0
Original line number Diff line number Diff line
@@ -49,6 +49,45 @@ struct lw_event { 
/* Avoid kmalloc() for most systems */

static struct lw_event singleevent;



static unsigned char default_operstate(const struct net_device *dev)

{

	if (!netif_carrier_ok(dev))

		return (dev->ifindex != dev->iflink ?

			IF_OPER_LOWERLAYERDOWN : IF_OPER_DOWN);



	if (netif_dormant(dev))

		return IF_OPER_DORMANT;



	return IF_OPER_UP;

}





static void rfc2863_policy(struct net_device *dev)

{

	unsigned char operstate = default_operstate(dev);



	if (operstate == dev->operstate)

		return;



	write_lock_bh(&dev_base_lock);



	switch(dev->link_mode) {

	case IF_LINK_MODE_DORMANT:

		if (operstate == IF_OPER_UP)

			operstate = IF_OPER_DORMANT;

		break;



	case IF_LINK_MODE_DEFAULT:

	default:

		break;

	};



	dev->operstate = operstate;



	write_unlock_bh(&dev_base_lock);

}





/* Must be called with the rtnl semaphore held */

void linkwatch_run_queue(void)

{
@@ -74,6 +113,7 @@ void linkwatch_run_queue(void) 
		 */

		clear_bit(__LINK_STATE_LINKWATCH_PENDING, &dev->state);



		rfc2863_policy(dev);

		if (dev->flags & IFF_UP) {

			if (netif_carrier_ok(dev)) {

				WARN_ON(dev->qdisc_sleeping == &noop_qdisc);

CRA Git | Maintained and supported by SUSTech CRA and CCSE