Commit e1bd4d3d authored by Eric W. Biederman's avatar Eric W. Biederman Committed by David S. Miller
Browse files

netpoll: Move all receive processing under CONFIG_NETPOLL_TRAP 



Make rx_skb_hook, and rx in struct netpoll depend on
CONFIG_NETPOLL_TRAP Make rx_lock, rx_np, and neigh_tx in struct
netpoll_info depend on CONFIG_NETPOLL_TRAP

Make the functions netpoll_rx_on, netpoll_rx, and netpoll_receive_skb
no-ops when CONFIG_NETPOLL_TRAP is not set.

Only build netpoll_neigh_reply, checksum_udp service_neigh_queue,
pkt_is_ns, and __netpoll_rx when CONFIG_NETPOLL_TRAP is defined.

Add helper functions netpoll_trap_setup, netpoll_trap_setup_info,
netpoll_trap_cleanup, and netpoll_trap_cleanup_info that initialize
and cleanup the struct netpoll and struct netpoll_info receive
specific fields when CONFIG_NETPOLL_TRAP is enabled and do nothing
otherwise.

Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 18b37535

include/linux/netpoll.h

+40 −33
Original line number Diff line number Diff line
@@ -24,32 +24,38 @@ struct netpoll { 
	struct net_device *dev;

	char dev_name[IFNAMSIZ];

	const char *name;

	void (*rx_skb_hook)(struct netpoll *np, int source, struct sk_buff *skb,

			    int offset, int len);



	union inet_addr local_ip, remote_ip;

	bool ipv6;

	u16 local_port, remote_port;

	u8 remote_mac[ETH_ALEN];



	struct list_head rx; /* rx_np list element */

	struct work_struct cleanup_work;



#ifdef CONFIG_NETPOLL_TRAP

	void (*rx_skb_hook)(struct netpoll *np, int source, struct sk_buff *skb,

			    int offset, int len);

	struct list_head rx; /* rx_np list element */

#endif

};



struct netpoll_info {

	atomic_t refcnt;



	spinlock_t rx_lock;

	struct semaphore dev_lock;

	struct list_head rx_np; /* netpolls that registered an rx_skb_hook */



	struct sk_buff_head neigh_tx; /* list of neigh requests to reply to */

	struct sk_buff_head txq;



	struct delayed_work tx_work;



	struct netpoll *netpoll;

	struct rcu_head rcu;



#ifdef CONFIG_NETPOLL_TRAP

	spinlock_t rx_lock;

	struct list_head rx_np; /* netpolls that registered an rx_skb_hook */

	struct sk_buff_head neigh_tx; /* list of neigh requests to reply to */

#endif

};



#ifdef CONFIG_NETPOLL
@@ -68,7 +74,6 @@ int netpoll_setup(struct netpoll *np); 
void __netpoll_cleanup(struct netpoll *np);

void __netpoll_free_async(struct netpoll *np);

void netpoll_cleanup(struct netpoll *np);

int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo);

void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,

			     struct net_device *dev);

static inline void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb)
@@ -82,25 +87,12 @@ static inline void netpoll_send_skb(struct netpoll *np, struct sk_buff *skb) 
#ifdef CONFIG_NETPOLL_TRAP

int netpoll_trap(void);

void netpoll_set_trap(int trap);

int __netpoll_rx(struct sk_buff *skb, struct netpoll_info *npinfo);

static inline bool netpoll_rx_processing(struct netpoll_info *npinfo)

{

	return !list_empty(&npinfo->rx_np);

}

#else

static inline int netpoll_trap(void)

{

	return 0;

}

static inline void netpoll_set_trap(int trap)

{

}

static inline bool netpoll_rx_processing(struct netpoll_info *npinfo)

{

	return false;

}

#endif



#ifdef CONFIG_NETPOLL

static inline bool netpoll_rx_on(struct sk_buff *skb)

{

	struct netpoll_info *npinfo = rcu_dereference_bh(skb->dev->npinfo);
@@ -138,6 +130,33 @@ static inline int netpoll_receive_skb(struct sk_buff *skb) 
	return 0;

}



#else

static inline int netpoll_trap(void)

{

	return 0;

}

static inline void netpoll_set_trap(int trap)

{

}

static inline bool netpoll_rx_processing(struct netpoll_info *npinfo)

{

	return false;

}

static inline bool netpoll_rx(struct sk_buff *skb)

{

	return false;

}

static inline bool netpoll_rx_on(struct sk_buff *skb)

{

	return false;

}

static inline int netpoll_receive_skb(struct sk_buff *skb)

{

	return 0;

}

#endif



#ifdef CONFIG_NETPOLL

static inline void *netpoll_poll_lock(struct napi_struct *napi)

{

	struct net_device *dev = napi->dev;
@@ -166,18 +185,6 @@ static inline bool netpoll_tx_running(struct net_device *dev) 
}



#else

static inline bool netpoll_rx(struct sk_buff *skb)

{

	return false;

}

static inline bool netpoll_rx_on(struct sk_buff *skb)

{

	return false;

}

static inline int netpoll_receive_skb(struct sk_buff *skb)

{

	return 0;

}

static inline void *netpoll_poll_lock(struct napi_struct *napi)

{

	return NULL;

net/core/netpoll.c

+64 −17
Original line number Diff line number Diff line
@@ -48,6 +48,7 @@ static struct sk_buff_head skb_pool; 


#ifdef CONFIG_NETPOLL_TRAP

static atomic_t trapped;

static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo);

#endif



DEFINE_STATIC_SRCU(netpoll_srcu);
@@ -61,7 +62,6 @@ DEFINE_STATIC_SRCU(netpoll_srcu); 
	 MAX_UDP_CHUNK)



static void zap_completion_queue(void);

static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo);

static void netpoll_async_cleanup(struct work_struct *work);



static unsigned int carrier_timeout = 4;
@@ -109,6 +109,7 @@ static void queue_process(struct work_struct *work) 
	}

}



#ifdef CONFIG_NETPOLL_TRAP

static __sum16 checksum_udp(struct sk_buff *skb, struct udphdr *uh,

			    unsigned short ulen, __be32 saddr, __be32 daddr)

{
@@ -127,6 +128,7 @@ static __sum16 checksum_udp(struct sk_buff *skb, struct udphdr *uh, 


	return __skb_checksum_complete(skb);

}

#endif /* CONFIG_NETPOLL_TRAP */



/*

 * Check whether delayed processing was scheduled for our NIC. If so,
@@ -179,6 +181,7 @@ static void poll_napi(struct net_device *dev, int budget) 
	}

}



#ifdef CONFIG_NETPOLL_TRAP

static void service_neigh_queue(struct net_device *dev,

				struct netpoll_info *npi)

{
@@ -197,6 +200,12 @@ static void service_neigh_queue(struct net_device *dev, 
	while ((skb = skb_dequeue(&npi->neigh_tx)))

		netpoll_neigh_reply(skb, npi);

}

#else /* !CONFIG_NETPOLL_TRAP */

static inline void service_neigh_queue(struct net_device *dev,

				struct netpoll_info *npi)

{

}

#endif /* CONFIG_NETPOLL_TRAP */



static void netpoll_poll_dev(struct net_device *dev)

{
@@ -522,6 +531,7 @@ void netpoll_send_udp(struct netpoll *np, const char *msg, int len) 
}

EXPORT_SYMBOL(netpoll_send_udp);



#ifdef CONFIG_NETPOLL_TRAP

static void netpoll_neigh_reply(struct sk_buff *skb, struct netpoll_info *npinfo)

{

	int size, type = ARPOP_REPLY;
@@ -900,6 +910,55 @@ out: 
	return 0;

}



static void netpoll_trap_setup_info(struct netpoll_info *npinfo)

{

	INIT_LIST_HEAD(&npinfo->rx_np);

	spin_lock_init(&npinfo->rx_lock);

	skb_queue_head_init(&npinfo->neigh_tx);

}



static void netpoll_trap_cleanup_info(struct netpoll_info *npinfo)

{

	skb_queue_purge(&npinfo->neigh_tx);

}



static void netpoll_trap_setup(struct netpoll *np, struct netpoll_info *npinfo)

{

	unsigned long flags;

	if (np->rx_skb_hook) {

		spin_lock_irqsave(&npinfo->rx_lock, flags);

		list_add_tail(&np->rx, &npinfo->rx_np);

		spin_unlock_irqrestore(&npinfo->rx_lock, flags);

	}

}



static void netpoll_trap_cleanup(struct netpoll *np, struct netpoll_info *npinfo)

{

	unsigned long flags;

	if (!list_empty(&npinfo->rx_np)) {

		spin_lock_irqsave(&npinfo->rx_lock, flags);

		list_del(&np->rx);

		spin_unlock_irqrestore(&npinfo->rx_lock, flags);

	}

}



#else /* !CONFIG_NETPOLL_TRAP */

static inline void netpoll_trap_setup_info(struct netpoll_info *npinfo)

{

}

static inline void netpoll_trap_cleanup_info(struct netpoll_info *npinfo)

{

}

static inline

void netpoll_trap_setup(struct netpoll *np, struct netpoll_info *npinfo)

{

}

static inline

void netpoll_trap_cleanup(struct netpoll *np, struct netpoll_info *npinfo)

{

}

#endif /* CONFIG_NETPOLL_TRAP */



void netpoll_print_options(struct netpoll *np)

{

	np_info(np, "local port %d\n", np->local_port);
@@ -1023,7 +1082,6 @@ int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp) 
{

	struct netpoll_info *npinfo;

	const struct net_device_ops *ops;

	unsigned long flags;

	int err;



	np->dev = ndev;
@@ -1045,11 +1103,9 @@ int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp) 
			goto out;

		}



		INIT_LIST_HEAD(&npinfo->rx_np);

		netpoll_trap_setup_info(npinfo);



		spin_lock_init(&npinfo->rx_lock);

		sema_init(&npinfo->dev_lock, 1);

		skb_queue_head_init(&npinfo->neigh_tx);

		skb_queue_head_init(&npinfo->txq);

		INIT_DELAYED_WORK(&npinfo->tx_work, queue_process);
@@ -1068,11 +1124,7 @@ int __netpoll_setup(struct netpoll *np, struct net_device *ndev, gfp_t gfp) 


	npinfo->netpoll = np;



	if (np->rx_skb_hook) {

		spin_lock_irqsave(&npinfo->rx_lock, flags);

		list_add_tail(&np->rx, &npinfo->rx_np);

		spin_unlock_irqrestore(&npinfo->rx_lock, flags);

	}

	netpoll_trap_setup(np, npinfo);



	/* last thing to do is link it to the net device structure */

	rcu_assign_pointer(ndev->npinfo, npinfo);
@@ -1222,7 +1274,7 @@ static void rcu_cleanup_netpoll_info(struct rcu_head *rcu_head) 
	struct netpoll_info *npinfo =

			container_of(rcu_head, struct netpoll_info, rcu);



	skb_queue_purge(&npinfo->neigh_tx);

	netpoll_trap_cleanup_info(npinfo);

	skb_queue_purge(&npinfo->txq);



	/* we can't call cancel_delayed_work_sync here, as we are in softirq */
@@ -1238,7 +1290,6 @@ static void rcu_cleanup_netpoll_info(struct rcu_head *rcu_head) 
void __netpoll_cleanup(struct netpoll *np)

{

	struct netpoll_info *npinfo;

	unsigned long flags;



	/* rtnl_dereference would be preferable here but

	 * rcu_cleanup_netpoll path can put us in here safely without
@@ -1248,11 +1299,7 @@ void __netpoll_cleanup(struct netpoll *np) 
	if (!npinfo)

		return;



	if (!list_empty(&npinfo->rx_np)) {

		spin_lock_irqsave(&npinfo->rx_lock, flags);

		list_del(&np->rx);

		spin_unlock_irqrestore(&npinfo->rx_lock, flags);

	}

	netpoll_trap_cleanup(np, npinfo);



	synchronize_srcu(&netpoll_srcu);

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