linux-stable/include/net/lwtunnel.h
Robert Shearman 88ff7334f2 net: Specify the owning module for lwtunnel ops
Modules implementing lwtunnel ops should not be allowed to unload
while there is state alive using those ops, so specify the owning
module for all lwtunnel ops.

Signed-off-by: Robert Shearman <rshearma@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-24 16:21:36 -05:00

233 lines
5.4 KiB
C

#ifndef __NET_LWTUNNEL_H
#define __NET_LWTUNNEL_H 1
#include <linux/lwtunnel.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/types.h>
#include <net/route.h>
#define LWTUNNEL_HASH_BITS 7
#define LWTUNNEL_HASH_SIZE (1 << LWTUNNEL_HASH_BITS)
/* lw tunnel state flags */
#define LWTUNNEL_STATE_OUTPUT_REDIRECT BIT(0)
#define LWTUNNEL_STATE_INPUT_REDIRECT BIT(1)
#define LWTUNNEL_STATE_XMIT_REDIRECT BIT(2)
enum {
LWTUNNEL_XMIT_DONE,
LWTUNNEL_XMIT_CONTINUE,
};
struct lwtunnel_state {
__u16 type;
__u16 flags;
__u16 headroom;
atomic_t refcnt;
int (*orig_output)(struct net *net, struct sock *sk, struct sk_buff *skb);
int (*orig_input)(struct sk_buff *);
struct rcu_head rcu;
__u8 data[0];
};
struct lwtunnel_encap_ops {
int (*build_state)(struct net_device *dev, struct nlattr *encap,
unsigned int family, const void *cfg,
struct lwtunnel_state **ts);
void (*destroy_state)(struct lwtunnel_state *lws);
int (*output)(struct net *net, struct sock *sk, struct sk_buff *skb);
int (*input)(struct sk_buff *skb);
int (*fill_encap)(struct sk_buff *skb,
struct lwtunnel_state *lwtstate);
int (*get_encap_size)(struct lwtunnel_state *lwtstate);
int (*cmp_encap)(struct lwtunnel_state *a, struct lwtunnel_state *b);
int (*xmit)(struct sk_buff *skb);
struct module *owner;
};
#ifdef CONFIG_LWTUNNEL
void lwtstate_free(struct lwtunnel_state *lws);
static inline struct lwtunnel_state *
lwtstate_get(struct lwtunnel_state *lws)
{
if (lws)
atomic_inc(&lws->refcnt);
return lws;
}
static inline void lwtstate_put(struct lwtunnel_state *lws)
{
if (!lws)
return;
if (atomic_dec_and_test(&lws->refcnt))
lwtstate_free(lws);
}
static inline bool lwtunnel_output_redirect(struct lwtunnel_state *lwtstate)
{
if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_OUTPUT_REDIRECT))
return true;
return false;
}
static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
{
if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_INPUT_REDIRECT))
return true;
return false;
}
static inline bool lwtunnel_xmit_redirect(struct lwtunnel_state *lwtstate)
{
if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_XMIT_REDIRECT))
return true;
return false;
}
static inline unsigned int lwtunnel_headroom(struct lwtunnel_state *lwtstate,
unsigned int mtu)
{
if ((lwtunnel_xmit_redirect(lwtstate) ||
lwtunnel_output_redirect(lwtstate)) && lwtstate->headroom < mtu)
return lwtstate->headroom;
return 0;
}
int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
unsigned int num);
int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
unsigned int num);
int lwtunnel_valid_encap_type(u16 encap_type);
int lwtunnel_valid_encap_type_attr(struct nlattr *attr, int len);
int lwtunnel_build_state(struct net_device *dev, u16 encap_type,
struct nlattr *encap,
unsigned int family, const void *cfg,
struct lwtunnel_state **lws);
int lwtunnel_fill_encap(struct sk_buff *skb,
struct lwtunnel_state *lwtstate);
int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate);
struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len);
int lwtunnel_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b);
int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb);
int lwtunnel_input(struct sk_buff *skb);
int lwtunnel_xmit(struct sk_buff *skb);
#else
static inline void lwtstate_free(struct lwtunnel_state *lws)
{
}
static inline struct lwtunnel_state *
lwtstate_get(struct lwtunnel_state *lws)
{
return lws;
}
static inline void lwtstate_put(struct lwtunnel_state *lws)
{
}
static inline bool lwtunnel_output_redirect(struct lwtunnel_state *lwtstate)
{
return false;
}
static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
{
return false;
}
static inline bool lwtunnel_xmit_redirect(struct lwtunnel_state *lwtstate)
{
return false;
}
static inline unsigned int lwtunnel_headroom(struct lwtunnel_state *lwtstate,
unsigned int mtu)
{
return 0;
}
static inline int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
unsigned int num)
{
return -EOPNOTSUPP;
}
static inline int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
unsigned int num)
{
return -EOPNOTSUPP;
}
static inline int lwtunnel_valid_encap_type(u16 encap_type)
{
return -EOPNOTSUPP;
}
static inline int lwtunnel_valid_encap_type_attr(struct nlattr *attr, int len)
{
return -EOPNOTSUPP;
}
static inline int lwtunnel_build_state(struct net_device *dev, u16 encap_type,
struct nlattr *encap,
unsigned int family, const void *cfg,
struct lwtunnel_state **lws)
{
return -EOPNOTSUPP;
}
static inline int lwtunnel_fill_encap(struct sk_buff *skb,
struct lwtunnel_state *lwtstate)
{
return 0;
}
static inline int lwtunnel_get_encap_size(struct lwtunnel_state *lwtstate)
{
return 0;
}
static inline struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len)
{
return NULL;
}
static inline int lwtunnel_cmp_encap(struct lwtunnel_state *a,
struct lwtunnel_state *b)
{
return 0;
}
static inline int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb)
{
return -EOPNOTSUPP;
}
static inline int lwtunnel_input(struct sk_buff *skb)
{
return -EOPNOTSUPP;
}
static inline int lwtunnel_xmit(struct sk_buff *skb)
{
return -EOPNOTSUPP;
}
#endif /* CONFIG_LWTUNNEL */
#define MODULE_ALIAS_RTNL_LWT(encap_type) MODULE_ALIAS("rtnl-lwt-" __stringify(encap_type))
#endif /* __NET_LWTUNNEL_H */