ia64/linux-2.6.18-xen.hg

view net/802/psnap.c @ 871:9cbcc9008446

xen/x86: don't initialize cpu_data[]'s apicid field on generic code

Afaict, this is not only redundant with the intialization done in
drivers/xen/core/smpboot.c, but actually results - at least for
secondary CPUs - in the Xen-specific value written to be later
overwritten with whatever the generic code determines (with no
guarantee that the two values are identical).

Signed-off-by: Jan Beulich <jbeulich@novell.com>
author Keir Fraser <keir.fraser@citrix.com>
date Thu May 14 10:09:15 2009 +0100 (2009-05-14)
parents 831230e53067
children
line source
1 /*
2 * SNAP data link layer. Derived from 802.2
3 *
4 * Alan Cox <Alan.Cox@linux.org>,
5 * from the 802.2 layer by Greg Page.
6 * Merged in additions from Greg Page's psnap.c.
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
12 */
14 #include <linux/module.h>
15 #include <linux/netdevice.h>
16 #include <linux/skbuff.h>
17 #include <net/datalink.h>
18 #include <net/llc.h>
19 #include <net/psnap.h>
20 #include <linux/mm.h>
21 #include <linux/in.h>
22 #include <linux/init.h>
24 static LIST_HEAD(snap_list);
25 static DEFINE_SPINLOCK(snap_lock);
26 static struct llc_sap *snap_sap;
28 /*
29 * Find a snap client by matching the 5 bytes.
30 */
31 static struct datalink_proto *find_snap_client(unsigned char *desc)
32 {
33 struct list_head *entry;
34 struct datalink_proto *proto = NULL, *p;
36 list_for_each_rcu(entry, &snap_list) {
37 p = list_entry(entry, struct datalink_proto, node);
38 if (!memcmp(p->type, desc, 5)) {
39 proto = p;
40 break;
41 }
42 }
43 return proto;
44 }
46 /*
47 * A SNAP packet has arrived
48 */
49 static int snap_rcv(struct sk_buff *skb, struct net_device *dev,
50 struct packet_type *pt, struct net_device *orig_dev)
51 {
52 int rc = 1;
53 struct datalink_proto *proto;
54 static struct packet_type snap_packet_type = {
55 .type = __constant_htons(ETH_P_SNAP),
56 };
58 rcu_read_lock();
59 proto = find_snap_client(skb->h.raw);
60 if (proto) {
61 /* Pass the frame on. */
62 skb->h.raw += 5;
63 skb_pull_rcsum(skb, 5);
64 rc = proto->rcvfunc(skb, dev, &snap_packet_type, orig_dev);
65 } else {
66 skb->sk = NULL;
67 kfree_skb(skb);
68 rc = 1;
69 }
71 rcu_read_unlock();
72 return rc;
73 }
75 /*
76 * Put a SNAP header on a frame and pass to 802.2
77 */
78 static int snap_request(struct datalink_proto *dl,
79 struct sk_buff *skb, u8 *dest)
80 {
81 memcpy(skb_push(skb, 5), dl->type, 5);
82 llc_build_and_send_ui_pkt(snap_sap, skb, dest, snap_sap->laddr.lsap);
83 return 0;
84 }
86 /*
87 * Set up the SNAP layer
88 */
89 EXPORT_SYMBOL(register_snap_client);
90 EXPORT_SYMBOL(unregister_snap_client);
92 static char snap_err_msg[] __initdata =
93 KERN_CRIT "SNAP - unable to register with 802.2\n";
95 static int __init snap_init(void)
96 {
97 snap_sap = llc_sap_open(0xAA, snap_rcv);
99 if (!snap_sap)
100 printk(snap_err_msg);
102 return 0;
103 }
105 module_init(snap_init);
107 static void __exit snap_exit(void)
108 {
109 llc_sap_put(snap_sap);
110 }
112 module_exit(snap_exit);
115 /*
116 * Register SNAP clients. We don't yet use this for IP.
117 */
118 struct datalink_proto *register_snap_client(unsigned char *desc,
119 int (*rcvfunc)(struct sk_buff *,
120 struct net_device *,
121 struct packet_type *,
122 struct net_device *))
123 {
124 struct datalink_proto *proto = NULL;
126 spin_lock_bh(&snap_lock);
128 if (find_snap_client(desc))
129 goto out;
131 proto = kmalloc(sizeof(*proto), GFP_ATOMIC);
132 if (proto) {
133 memcpy(proto->type, desc,5);
134 proto->rcvfunc = rcvfunc;
135 proto->header_length = 5 + 3; /* snap + 802.2 */
136 proto->request = snap_request;
137 list_add_rcu(&proto->node, &snap_list);
138 }
139 out:
140 spin_unlock_bh(&snap_lock);
142 synchronize_net();
143 return proto;
144 }
146 /*
147 * Unregister SNAP clients. Protocols no longer want to play with us ...
148 */
149 void unregister_snap_client(struct datalink_proto *proto)
150 {
151 spin_lock_bh(&snap_lock);
152 list_del_rcu(&proto->node);
153 spin_unlock_bh(&snap_lock);
155 synchronize_net();
157 kfree(proto);
158 }
160 MODULE_LICENSE("GPL");