Commit 62532da9 authored by Vlad Yasevich's avatar Vlad Yasevich Committed by David S. Miller
Browse files

net: Add generic packet offload infrastructure. 



Create a new data structure to contain the GRO/GSO callbacks and add
a new registration mechanism.

Singed-off-by: default avatarVlad Yasevich <vyasevic@redhat.com>

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent efad0c14

include/linux/netdevice.h

+14 −0
Original line number Diff line number Diff line
@@ -1521,6 +1521,17 @@ struct packet_type { 
	struct list_head	list;

};



struct packet_offload {

	__be16			type;	/* This is really htons(ether_type). */

	struct sk_buff		*(*gso_segment)(struct sk_buff *skb,

						netdev_features_t features);

	int			(*gso_send_check)(struct sk_buff *skb);

	struct sk_buff		**(*gro_receive)(struct sk_buff **head,

					       struct sk_buff *skb);

	int			(*gro_complete)(struct sk_buff *skb);

	struct list_head	list;

};



#include <linux/notifier.h>



/* netdevice notifier chain. Please remember to update the rtnetlink
@@ -1615,6 +1626,9 @@ extern struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short 
extern void		dev_add_pack(struct packet_type *pt);

extern void		dev_remove_pack(struct packet_type *pt);

extern void		__dev_remove_pack(struct packet_type *pt);

extern void		dev_add_offload(struct packet_offload *po);

extern void		dev_remove_offload(struct packet_offload *po);

extern void		__dev_remove_offload(struct packet_offload *po);



extern struct net_device	*dev_get_by_flags_rcu(struct net *net, unsigned short flags,

						      unsigned short mask);

net/core/dev.c

+80 −0
Original line number Diff line number Diff line
@@ -176,8 +176,10 @@ 
#define PTYPE_HASH_MASK	(PTYPE_HASH_SIZE - 1)



static DEFINE_SPINLOCK(ptype_lock);

static DEFINE_SPINLOCK(offload_lock);

static struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;

static struct list_head ptype_all __read_mostly;	/* Taps */

static struct list_head offload_base __read_mostly;



/*

 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
@@ -470,6 +472,82 @@ void dev_remove_pack(struct packet_type *pt) 
}

EXPORT_SYMBOL(dev_remove_pack);





/**

 *	dev_add_offload - register offload handlers

 *	@po: protocol offload declaration

 *

 *	Add protocol offload handlers to the networking stack. The passed

 *	&proto_offload is linked into kernel lists and may not be freed until

 *	it has been removed from the kernel lists.

 *

 *	This call does not sleep therefore it can not

 *	guarantee all CPU's that are in middle of receiving packets

 *	will see the new offload handlers (until the next received packet).

 */

void dev_add_offload(struct packet_offload *po)

{

	struct list_head *head = &offload_base;



	spin_lock(&offload_lock);

	list_add_rcu(&po->list, head);

	spin_unlock(&offload_lock);

}

EXPORT_SYMBOL(dev_add_offload);



/**

 *	__dev_remove_offload	 - remove offload handler

 *	@po: packet offload declaration

 *

 *	Remove a protocol offload handler that was previously added to the

 *	kernel offload handlers by dev_add_offload(). The passed &offload_type

 *	is removed from the kernel lists and can be freed or reused once this

 *	function returns.

 *

 *      The packet type might still be in use by receivers

 *	and must not be freed until after all the CPU's have gone

 *	through a quiescent state.

 */

void __dev_remove_offload(struct packet_offload *po)

{

	struct list_head *head = &offload_base;

	struct packet_offload *po1;



	spin_lock(&ptype_lock);



	list_for_each_entry(po1, head, list) {

		if (po == po1) {

			list_del_rcu(&po->list);

			goto out;

		}

	}



	pr_warn("dev_remove_offload: %p not found\n", po);

out:

	spin_unlock(&ptype_lock);

}

EXPORT_SYMBOL(__dev_remove_offload);



/**

 *	dev_remove_offload	 - remove packet offload handler

 *	@po: packet offload declaration

 *

 *	Remove a packet offload handler that was previously added to the kernel

 *	offload handlers by dev_add_offload(). The passed &offload_type is

 *	removed from the kernel lists and can be freed or reused once this

 *	function returns.

 *

 *	This call sleeps to guarantee that no CPU is looking at the packet

 *	type after return.

 */

void dev_remove_offload(struct packet_offload *po)

{

	__dev_remove_offload(po);



	synchronize_net();

}

EXPORT_SYMBOL(dev_remove_offload);



/******************************************************************************



		      Device Boot-time Settings Routines
@@ -6661,6 +6739,8 @@ static int __init net_dev_init(void) 
	for (i = 0; i < PTYPE_HASH_SIZE; i++)

		INIT_LIST_HEAD(&ptype_base[i]);



	INIT_LIST_HEAD(&offload_base);



	if (register_pernet_subsys(&netdev_net_ops))

		goto out;