alistair23-linux/drivers/net/wireguard/device.h
Jason A. Donenfeld dcfea72e79 net: introduce skb_list_walk_safe for skb segment walking
As part of the continual effort to remove direct usage of skb->next and
skb->prev, this patch adds a helper for iterating through the
singly-linked variant of skb lists, which are used for lists of GSO
packet. The name "skb_list_..." has been chosen to match the existing
function, "kfree_skb_list, which also operates on these singly-linked
lists, and the "..._walk_safe" part is the same idiom as elsewhere in
the kernel.

This patch removes the helper from wireguard and puts it into
linux/skbuff.h, while making it a bit more robust for general usage. In
particular, parenthesis are added around the macro argument usage, and it
now accounts for trying to iterate through an already-null skb pointer,
which will simply run the iteration zero times. This latter enhancement
means it can be used to replace both do { ... } while and while (...)
open-coded idioms.

This should take care of these three possible usages, which match all
current methods of iterations.

skb_list_walk_safe(segs, skb, next) { ... }
skb_list_walk_safe(skb, skb, next) { ... }
skb_list_walk_safe(segs, skb, segs) { ... }

Gcc appears to generate efficient code for each of these.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-08 15:19:54 -08:00

66 lines
1.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
*/
#ifndef _WG_DEVICE_H
#define _WG_DEVICE_H
#include "noise.h"
#include "allowedips.h"
#include "peerlookup.h"
#include "cookie.h"
#include <linux/types.h>
#include <linux/netdevice.h>
#include <linux/workqueue.h>
#include <linux/mutex.h>
#include <linux/net.h>
#include <linux/ptr_ring.h>
struct wg_device;
struct multicore_worker {
void *ptr;
struct work_struct work;
};
struct crypt_queue {
struct ptr_ring ring;
union {
struct {
struct multicore_worker __percpu *worker;
int last_cpu;
};
struct work_struct work;
};
};
struct wg_device {
struct net_device *dev;
struct crypt_queue encrypt_queue, decrypt_queue;
struct sock __rcu *sock4, *sock6;
struct net *creating_net;
struct noise_static_identity static_identity;
struct workqueue_struct *handshake_receive_wq, *handshake_send_wq;
struct workqueue_struct *packet_crypt_wq;
struct sk_buff_head incoming_handshakes;
int incoming_handshake_cpu;
struct multicore_worker __percpu *incoming_handshakes_worker;
struct cookie_checker cookie_checker;
struct pubkey_hashtable *peer_hashtable;
struct index_hashtable *index_hashtable;
struct allowedips peer_allowedips;
struct mutex device_update_lock, socket_update_lock;
struct list_head device_list, peer_list;
unsigned int num_peers, device_update_gen;
u32 fwmark;
u16 incoming_port;
bool have_creating_net_ref;
};
int wg_device_init(void);
void wg_device_uninit(void);
#endif /* _WG_DEVICE_H */