kernel_optimize_test/net/llc/llc_proc.c
Jules Irenge 8e0f8ccfb0 net: Add missing annotation for llc_seq_start()
Sparse reports a warning at llc_seq_start()

warning: context imbalance in llc_seq_start() - wrong count at exit
The root cause is the msiing annotation at llc_seq_start()

Add the missing __acquires(RCU) annotation

Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-24 13:26:49 -08:00

252 lines
6.0 KiB
C

/*
* proc_llc.c - proc interface for LLC
*
* Copyright (c) 2001 by Jay Schulist <jschlst@samba.org>
* 2002-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
*
* This program can be redistributed or modified under the terms of the
* GNU General Public License as published by the Free Software Foundation.
* This program is distributed without any warranty or implied warranty
* of merchantability or fitness for a particular purpose.
*
* See the GNU General Public License for more details.
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/proc_fs.h>
#include <linux/errno.h>
#include <linux/seq_file.h>
#include <linux/export.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include <net/llc.h>
#include <net/llc_c_ac.h>
#include <net/llc_c_ev.h>
#include <net/llc_c_st.h>
#include <net/llc_conn.h>
static void llc_ui_format_mac(struct seq_file *seq, u8 *addr)
{
seq_printf(seq, "%pM", addr);
}
static struct sock *llc_get_sk_idx(loff_t pos)
{
struct llc_sap *sap;
struct sock *sk = NULL;
int i;
list_for_each_entry_rcu(sap, &llc_sap_list, node) {
spin_lock_bh(&sap->sk_lock);
for (i = 0; i < LLC_SK_LADDR_HASH_ENTRIES; i++) {
struct hlist_nulls_head *head = &sap->sk_laddr_hash[i];
struct hlist_nulls_node *node;
sk_nulls_for_each(sk, node, head) {
if (!pos)
goto found; /* keep the lock */
--pos;
}
}
spin_unlock_bh(&sap->sk_lock);
}
sk = NULL;
found:
return sk;
}
static void *llc_seq_start(struct seq_file *seq, loff_t *pos) __acquires(RCU)
{
loff_t l = *pos;
rcu_read_lock_bh();
return l ? llc_get_sk_idx(--l) : SEQ_START_TOKEN;
}
static struct sock *laddr_hash_next(struct llc_sap *sap, int bucket)
{
struct hlist_nulls_node *node;
struct sock *sk = NULL;
while (++bucket < LLC_SK_LADDR_HASH_ENTRIES)
sk_nulls_for_each(sk, node, &sap->sk_laddr_hash[bucket])
goto out;
out:
return sk;
}
static void *llc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
struct sock* sk, *next;
struct llc_sock *llc;
struct llc_sap *sap;
++*pos;
if (v == SEQ_START_TOKEN) {
sk = llc_get_sk_idx(0);
goto out;
}
sk = v;
next = sk_nulls_next(sk);
if (next) {
sk = next;
goto out;
}
llc = llc_sk(sk);
sap = llc->sap;
sk = laddr_hash_next(sap, llc_sk_laddr_hashfn(sap, &llc->laddr));
if (sk)
goto out;
spin_unlock_bh(&sap->sk_lock);
list_for_each_entry_continue_rcu(sap, &llc_sap_list, node) {
spin_lock_bh(&sap->sk_lock);
sk = laddr_hash_next(sap, -1);
if (sk)
break; /* keep the lock */
spin_unlock_bh(&sap->sk_lock);
}
out:
return sk;
}
static void llc_seq_stop(struct seq_file *seq, void *v)
{
if (v && v != SEQ_START_TOKEN) {
struct sock *sk = v;
struct llc_sock *llc = llc_sk(sk);
struct llc_sap *sap = llc->sap;
spin_unlock_bh(&sap->sk_lock);
}
rcu_read_unlock_bh();
}
static int llc_seq_socket_show(struct seq_file *seq, void *v)
{
struct sock* sk;
struct llc_sock *llc;
if (v == SEQ_START_TOKEN) {
seq_puts(seq, "SKt Mc local_mac_sap remote_mac_sap "
" tx_queue rx_queue st uid link\n");
goto out;
}
sk = v;
llc = llc_sk(sk);
/* FIXME: check if the address is multicast */
seq_printf(seq, "%2X %2X ", sk->sk_type, 0);
if (llc->dev)
llc_ui_format_mac(seq, llc->dev->dev_addr);
else {
u8 addr[6] = {0,0,0,0,0,0};
llc_ui_format_mac(seq, addr);
}
seq_printf(seq, "@%02X ", llc->sap->laddr.lsap);
llc_ui_format_mac(seq, llc->daddr.mac);
seq_printf(seq, "@%02X %8d %8d %2d %3u %4d\n", llc->daddr.lsap,
sk_wmem_alloc_get(sk),
sk_rmem_alloc_get(sk) - llc->copied_seq,
sk->sk_state,
from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
llc->link);
out:
return 0;
}
static const char *const llc_conn_state_names[] = {
[LLC_CONN_STATE_ADM] = "adm",
[LLC_CONN_STATE_SETUP] = "setup",
[LLC_CONN_STATE_NORMAL] = "normal",
[LLC_CONN_STATE_BUSY] = "busy",
[LLC_CONN_STATE_REJ] = "rej",
[LLC_CONN_STATE_AWAIT] = "await",
[LLC_CONN_STATE_AWAIT_BUSY] = "await_busy",
[LLC_CONN_STATE_AWAIT_REJ] = "await_rej",
[LLC_CONN_STATE_D_CONN] = "d_conn",
[LLC_CONN_STATE_RESET] = "reset",
[LLC_CONN_STATE_ERROR] = "error",
[LLC_CONN_STATE_TEMP] = "temp",
};
static int llc_seq_core_show(struct seq_file *seq, void *v)
{
struct sock* sk;
struct llc_sock *llc;
if (v == SEQ_START_TOKEN) {
seq_puts(seq, "Connection list:\n"
"dsap state retr txw rxw pf ff sf df rs cs "
"tack tpfc trs tbs blog busr\n");
goto out;
}
sk = v;
llc = llc_sk(sk);
seq_printf(seq, " %02X %-10s %3d %3d %3d %2d %2d %2d %2d %2d %2d "
"%4d %4d %3d %3d %4d %4d\n",
llc->daddr.lsap, llc_conn_state_names[llc->state],
llc->retry_count, llc->k, llc->rw, llc->p_flag, llc->f_flag,
llc->s_flag, llc->data_flag, llc->remote_busy_flag,
llc->cause_flag, timer_pending(&llc->ack_timer.timer),
timer_pending(&llc->pf_cycle_timer.timer),
timer_pending(&llc->rej_sent_timer.timer),
timer_pending(&llc->busy_state_timer.timer),
!!sk->sk_backlog.tail, !!sk->sk_lock.owned);
out:
return 0;
}
static const struct seq_operations llc_seq_socket_ops = {
.start = llc_seq_start,
.next = llc_seq_next,
.stop = llc_seq_stop,
.show = llc_seq_socket_show,
};
static const struct seq_operations llc_seq_core_ops = {
.start = llc_seq_start,
.next = llc_seq_next,
.stop = llc_seq_stop,
.show = llc_seq_core_show,
};
static struct proc_dir_entry *llc_proc_dir;
int __init llc_proc_init(void)
{
int rc = -ENOMEM;
struct proc_dir_entry *p;
llc_proc_dir = proc_mkdir("llc", init_net.proc_net);
if (!llc_proc_dir)
goto out;
p = proc_create_seq("socket", 0444, llc_proc_dir, &llc_seq_socket_ops);
if (!p)
goto out_socket;
p = proc_create_seq("core", 0444, llc_proc_dir, &llc_seq_core_ops);
if (!p)
goto out_core;
rc = 0;
out:
return rc;
out_core:
remove_proc_entry("socket", llc_proc_dir);
out_socket:
remove_proc_entry("llc", init_net.proc_net);
goto out;
}
void llc_proc_exit(void)
{
remove_proc_entry("socket", llc_proc_dir);
remove_proc_entry("core", llc_proc_dir);
remove_proc_entry("llc", init_net.proc_net);
}