rcu: Better explain the condition parameter of rcu_dereference_check()
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / net / llc / llc_proc.c
blob7af1ff2d1f1974ff339865beece31e8c09d6d449
1 /*
2 * proc_llc.c - proc interface for LLC
4 * Copyright (c) 2001 by Jay Schulist <jschlst@samba.org>
5 * 2002-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
7 * This program can be redistributed or modified under the terms of the
8 * GNU General Public License as published by the Free Software Foundation.
9 * This program is distributed without any warranty or implied warranty
10 * of merchantability or fitness for a particular purpose.
12 * See the GNU General Public License for more details.
15 #include <linux/init.h>
16 #include <linux/kernel.h>
17 #include <linux/proc_fs.h>
18 #include <linux/errno.h>
19 #include <linux/seq_file.h>
20 #include <net/net_namespace.h>
21 #include <net/sock.h>
22 #include <net/llc.h>
23 #include <net/llc_c_ac.h>
24 #include <net/llc_c_ev.h>
25 #include <net/llc_c_st.h>
26 #include <net/llc_conn.h>
28 static void llc_ui_format_mac(struct seq_file *seq, u8 *addr)
30 seq_printf(seq, "%pM", addr);
33 static struct sock *llc_get_sk_idx(loff_t pos)
35 struct llc_sap *sap;
36 struct sock *sk = NULL;
37 int i;
39 list_for_each_entry_rcu(sap, &llc_sap_list, node) {
40 spin_lock_bh(&sap->sk_lock);
41 for (i = 0; i < LLC_SK_LADDR_HASH_ENTRIES; i++) {
42 struct hlist_nulls_head *head = &sap->sk_laddr_hash[i];
43 struct hlist_nulls_node *node;
45 sk_nulls_for_each(sk, node, head) {
46 if (!pos)
47 goto found; /* keep the lock */
48 --pos;
51 spin_unlock_bh(&sap->sk_lock);
53 sk = NULL;
54 found:
55 return sk;
58 static void *llc_seq_start(struct seq_file *seq, loff_t *pos)
60 loff_t l = *pos;
62 rcu_read_lock_bh();
63 return l ? llc_get_sk_idx(--l) : SEQ_START_TOKEN;
66 static struct sock *laddr_hash_next(struct llc_sap *sap, int bucket)
68 struct hlist_nulls_node *node;
69 struct sock *sk = NULL;
71 while (++bucket < LLC_SK_LADDR_HASH_ENTRIES)
72 sk_nulls_for_each(sk, node, &sap->sk_laddr_hash[bucket])
73 goto out;
75 out:
76 return sk;
79 static void *llc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
81 struct sock* sk, *next;
82 struct llc_sock *llc;
83 struct llc_sap *sap;
85 ++*pos;
86 if (v == SEQ_START_TOKEN) {
87 sk = llc_get_sk_idx(0);
88 goto out;
90 sk = v;
91 next = sk_nulls_next(sk);
92 if (next) {
93 sk = next;
94 goto out;
96 llc = llc_sk(sk);
97 sap = llc->sap;
98 sk = laddr_hash_next(sap, llc_sk_laddr_hashfn(sap, &llc->laddr));
99 if (sk)
100 goto out;
101 spin_unlock_bh(&sap->sk_lock);
102 list_for_each_entry_continue_rcu(sap, &llc_sap_list, node) {
103 spin_lock_bh(&sap->sk_lock);
104 sk = laddr_hash_next(sap, -1);
105 if (sk)
106 break; /* keep the lock */
107 spin_unlock_bh(&sap->sk_lock);
109 out:
110 return sk;
113 static void llc_seq_stop(struct seq_file *seq, void *v)
115 if (v && v != SEQ_START_TOKEN) {
116 struct sock *sk = v;
117 struct llc_sock *llc = llc_sk(sk);
118 struct llc_sap *sap = llc->sap;
120 spin_unlock_bh(&sap->sk_lock);
122 rcu_read_unlock_bh();
125 static int llc_seq_socket_show(struct seq_file *seq, void *v)
127 struct sock* sk;
128 struct llc_sock *llc;
130 if (v == SEQ_START_TOKEN) {
131 seq_puts(seq, "SKt Mc local_mac_sap remote_mac_sap "
132 " tx_queue rx_queue st uid link\n");
133 goto out;
135 sk = v;
136 llc = llc_sk(sk);
138 /* FIXME: check if the address is multicast */
139 seq_printf(seq, "%2X %2X ", sk->sk_type, 0);
141 if (llc->dev)
142 llc_ui_format_mac(seq, llc->dev->dev_addr);
143 else {
144 u8 addr[6] = {0,0,0,0,0,0};
145 llc_ui_format_mac(seq, addr);
147 seq_printf(seq, "@%02X ", llc->sap->laddr.lsap);
148 llc_ui_format_mac(seq, llc->daddr.mac);
149 seq_printf(seq, "@%02X %8d %8d %2d %3d %4d\n", llc->daddr.lsap,
150 sk_wmem_alloc_get(sk),
151 sk_rmem_alloc_get(sk) - llc->copied_seq,
152 sk->sk_state,
153 sk->sk_socket ? SOCK_INODE(sk->sk_socket)->i_uid : -1,
154 llc->link);
155 out:
156 return 0;
159 static const char *const llc_conn_state_names[] = {
160 [LLC_CONN_STATE_ADM] = "adm",
161 [LLC_CONN_STATE_SETUP] = "setup",
162 [LLC_CONN_STATE_NORMAL] = "normal",
163 [LLC_CONN_STATE_BUSY] = "busy",
164 [LLC_CONN_STATE_REJ] = "rej",
165 [LLC_CONN_STATE_AWAIT] = "await",
166 [LLC_CONN_STATE_AWAIT_BUSY] = "await_busy",
167 [LLC_CONN_STATE_AWAIT_REJ] = "await_rej",
168 [LLC_CONN_STATE_D_CONN] = "d_conn",
169 [LLC_CONN_STATE_RESET] = "reset",
170 [LLC_CONN_STATE_ERROR] = "error",
171 [LLC_CONN_STATE_TEMP] = "temp",
174 static int llc_seq_core_show(struct seq_file *seq, void *v)
176 struct sock* sk;
177 struct llc_sock *llc;
179 if (v == SEQ_START_TOKEN) {
180 seq_puts(seq, "Connection list:\n"
181 "dsap state retr txw rxw pf ff sf df rs cs "
182 "tack tpfc trs tbs blog busr\n");
183 goto out;
185 sk = v;
186 llc = llc_sk(sk);
188 seq_printf(seq, " %02X %-10s %3d %3d %3d %2d %2d %2d %2d %2d %2d "
189 "%4d %4d %3d %3d %4d %4d\n",
190 llc->daddr.lsap, llc_conn_state_names[llc->state],
191 llc->retry_count, llc->k, llc->rw, llc->p_flag, llc->f_flag,
192 llc->s_flag, llc->data_flag, llc->remote_busy_flag,
193 llc->cause_flag, timer_pending(&llc->ack_timer.timer),
194 timer_pending(&llc->pf_cycle_timer.timer),
195 timer_pending(&llc->rej_sent_timer.timer),
196 timer_pending(&llc->busy_state_timer.timer),
197 !!sk->sk_backlog.tail, !!sock_owned_by_user(sk));
198 out:
199 return 0;
202 static const struct seq_operations llc_seq_socket_ops = {
203 .start = llc_seq_start,
204 .next = llc_seq_next,
205 .stop = llc_seq_stop,
206 .show = llc_seq_socket_show,
209 static const struct seq_operations llc_seq_core_ops = {
210 .start = llc_seq_start,
211 .next = llc_seq_next,
212 .stop = llc_seq_stop,
213 .show = llc_seq_core_show,
216 static int llc_seq_socket_open(struct inode *inode, struct file *file)
218 return seq_open(file, &llc_seq_socket_ops);
221 static int llc_seq_core_open(struct inode *inode, struct file *file)
223 return seq_open(file, &llc_seq_core_ops);
226 static const struct file_operations llc_seq_socket_fops = {
227 .owner = THIS_MODULE,
228 .open = llc_seq_socket_open,
229 .read = seq_read,
230 .llseek = seq_lseek,
231 .release = seq_release,
234 static const struct file_operations llc_seq_core_fops = {
235 .owner = THIS_MODULE,
236 .open = llc_seq_core_open,
237 .read = seq_read,
238 .llseek = seq_lseek,
239 .release = seq_release,
242 static struct proc_dir_entry *llc_proc_dir;
244 int __init llc_proc_init(void)
246 int rc = -ENOMEM;
247 struct proc_dir_entry *p;
249 llc_proc_dir = proc_mkdir("llc", init_net.proc_net);
250 if (!llc_proc_dir)
251 goto out;
253 p = proc_create("socket", S_IRUGO, llc_proc_dir, &llc_seq_socket_fops);
254 if (!p)
255 goto out_socket;
257 p = proc_create("core", S_IRUGO, llc_proc_dir, &llc_seq_core_fops);
258 if (!p)
259 goto out_core;
261 rc = 0;
262 out:
263 return rc;
264 out_core:
265 remove_proc_entry("socket", llc_proc_dir);
266 out_socket:
267 remove_proc_entry("llc", init_net.proc_net);
268 goto out;
271 void llc_proc_exit(void)
273 remove_proc_entry("socket", llc_proc_dir);
274 remove_proc_entry("core", llc_proc_dir);
275 remove_proc_entry("llc", init_net.proc_net);