Initial import

1 files changed, 823 insertions, 0 deletions

diff --git a/net/phonet/socket.c b/net/phonet/socket.c
new file mode 100644
index 000000000..d575ef4e9
--- /dev/null
+++ b/net/phonet/socket.c
@@ -0,0 +1,823 @@
+/*
+ * File: socket.c
+ *
+ * Phonet sockets
+ *
+ * Copyright (C) 2008 Nokia Corporation.
+ *
+ * Authors: Sakari Ailus <sakari.ailus@nokia.com>
+ *          Rémi Denis-Courmont
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include <linux/gfp.h>
+#include <linux/kernel.h>
+#include <linux/net.h>
+#include <linux/poll.h>
+#include <net/sock.h>
+#include <net/tcp_states.h>
+
+#include <linux/phonet.h>
+#include <linux/export.h>
+#include <net/phonet/phonet.h>
+#include <net/phonet/pep.h>
+#include <net/phonet/pn_dev.h>
+
+static int pn_socket_release(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+
+	if (sk) {
+		sock->sk = NULL;
+		sk->sk_prot->close(sk, 0);
+	}
+	return 0;
+}
+
+#define PN_HASHSIZE	16
+#define PN_HASHMASK	(PN_HASHSIZE-1)
+
+
+static struct  {
+	struct hlist_head hlist[PN_HASHSIZE];
+	struct mutex lock;
+} pnsocks;
+
+void __init pn_sock_init(void)
+{
+	unsigned int i;
+
+	for (i = 0; i < PN_HASHSIZE; i++)
+		INIT_HLIST_HEAD(pnsocks.hlist + i);
+	mutex_init(&pnsocks.lock);
+}
+
+static struct hlist_head *pn_hash_list(u16 obj)
+{
+	return pnsocks.hlist + (obj & PN_HASHMASK);
+}
+
+/*
+ * Find address based on socket address, match only certain fields.
+ * Also grab sock if it was found. Remember to sock_put it later.
+ */
+struct sock *pn_find_sock_by_sa(struct net *net, const struct sockaddr_pn *spn)
+{
+	struct sock *sknode;
+	struct sock *rval = NULL;
+	u16 obj = pn_sockaddr_get_object(spn);
+	u8 res = spn->spn_resource;
+	struct hlist_head *hlist = pn_hash_list(obj);
+
+	rcu_read_lock();
+	sk_for_each_rcu(sknode, hlist) {
+		struct pn_sock *pn = pn_sk(sknode);
+		BUG_ON(!pn->sobject); /* unbound socket */
+
+		if (!net_eq(sock_net(sknode), net))
+			continue;
+		if (pn_port(obj)) {
+			/* Look up socket by port */
+			if (pn_port(pn->sobject) != pn_port(obj))
+				continue;
+		} else {
+			/* If port is zero, look up by resource */
+			if (pn->resource != res)
+				continue;
+		}
+		if (pn_addr(pn->sobject) &&
+		    pn_addr(pn->sobject) != pn_addr(obj))
+			continue;
+
+		rval = sknode;
+		sock_hold(sknode);
+		break;
+	}
+	rcu_read_unlock();
+
+	return rval;
+}
+
+/* Deliver a broadcast packet (only in bottom-half) */
+void pn_deliver_sock_broadcast(struct net *net, struct sk_buff *skb)
+{
+	struct hlist_head *hlist = pnsocks.hlist;
+	unsigned int h;
+
+	rcu_read_lock();
+	for (h = 0; h < PN_HASHSIZE; h++) {
+		struct sock *sknode;
+
+		sk_for_each(sknode, hlist) {
+			struct sk_buff *clone;
+
+			if (!net_eq(sock_net(sknode), net))
+				continue;
+			if (!sock_flag(sknode, SOCK_BROADCAST))
+				continue;
+
+			clone = skb_clone(skb, GFP_ATOMIC);
+			if (clone) {
+				sock_hold(sknode);
+				sk_receive_skb(sknode, clone, 0);
+			}
+		}
+		hlist++;
+	}
+	rcu_read_unlock();
+}
+
+void pn_sock_hash(struct sock *sk)
+{
+	struct hlist_head *hlist = pn_hash_list(pn_sk(sk)->sobject);
+
+	mutex_lock(&pnsocks.lock);
+	sk_add_node_rcu(sk, hlist);
+	mutex_unlock(&pnsocks.lock);
+}
+EXPORT_SYMBOL(pn_sock_hash);
+
+void pn_sock_unhash(struct sock *sk)
+{
+	mutex_lock(&pnsocks.lock);
+	sk_del_node_init_rcu(sk);
+	mutex_unlock(&pnsocks.lock);
+	pn_sock_unbind_all_res(sk);
+	synchronize_rcu();
+}
+EXPORT_SYMBOL(pn_sock_unhash);
+
+static DEFINE_MUTEX(port_mutex);
+
+static int pn_socket_bind(struct socket *sock, struct sockaddr *addr, int len)
+{
+	struct sock *sk = sock->sk;
+	struct pn_sock *pn = pn_sk(sk);
+	struct sockaddr_pn *spn = (struct sockaddr_pn *)addr;
+	int err;
+	u16 handle;
+	u8 saddr;
+
+	if (sk->sk_prot->bind)
+		return sk->sk_prot->bind(sk, addr, len);
+
+	if (len < sizeof(struct sockaddr_pn))
+		return -EINVAL;
+	if (spn->spn_family != AF_PHONET)
+		return -EAFNOSUPPORT;
+
+	handle = pn_sockaddr_get_object((struct sockaddr_pn *)addr);
+	saddr = pn_addr(handle);
+	if (saddr && phonet_address_lookup(sock_net(sk), saddr))
+		return -EADDRNOTAVAIL;
+
+	lock_sock(sk);
+	if (sk->sk_state != TCP_CLOSE || pn_port(pn->sobject)) {
+		err = -EINVAL; /* attempt to rebind */
+		goto out;
+	}
+	WARN_ON(sk_hashed(sk));
+	mutex_lock(&port_mutex);
+	err = sk->sk_prot->get_port(sk, pn_port(handle));
+	if (err)
+		goto out_port;
+
+	/* get_port() sets the port, bind() sets the address if applicable */
+	pn->sobject = pn_object(saddr, pn_port(pn->sobject));
+	pn->resource = spn->spn_resource;
+
+	/* Enable RX on the socket */
+	sk->sk_prot->hash(sk);
+out_port:
+	mutex_unlock(&port_mutex);
+out:
+	release_sock(sk);
+	return err;
+}
+
+static int pn_socket_autobind(struct socket *sock)
+{
+	struct sockaddr_pn sa;
+	int err;
+
+	memset(&sa, 0, sizeof(sa));
+	sa.spn_family = AF_PHONET;
+	err = pn_socket_bind(sock, (struct sockaddr *)&sa,
+				sizeof(struct sockaddr_pn));
+	if (err != -EINVAL)
+		return err;
+	BUG_ON(!pn_port(pn_sk(sock->sk)->sobject));
+	return 0; /* socket was already bound */
+}
+
+static int pn_socket_connect(struct socket *sock, struct sockaddr *addr,
+		int len, int flags)
+{
+	struct sock *sk = sock->sk;
+	struct pn_sock *pn = pn_sk(sk);
+	struct sockaddr_pn *spn = (struct sockaddr_pn *)addr;
+	struct task_struct *tsk = current;
+	long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
+	int err;
+
+	if (pn_socket_autobind(sock))
+		return -ENOBUFS;
+	if (len < sizeof(struct sockaddr_pn))
+		return -EINVAL;
+	if (spn->spn_family != AF_PHONET)
+		return -EAFNOSUPPORT;
+
+	lock_sock(sk);
+
+	switch (sock->state) {
+	case SS_UNCONNECTED:
+		if (sk->sk_state != TCP_CLOSE) {
+			err = -EISCONN;
+			goto out;
+		}
+		break;
+	case SS_CONNECTING:
+		err = -EALREADY;
+		goto out;
+	default:
+		err = -EISCONN;
+		goto out;
+	}
+
+	pn->dobject = pn_sockaddr_get_object(spn);
+	pn->resource = pn_sockaddr_get_resource(spn);
+	sock->state = SS_CONNECTING;
+
+	err = sk->sk_prot->connect(sk, addr, len);
+	if (err) {
+		sock->state = SS_UNCONNECTED;
+		pn->dobject = 0;
+		goto out;
+	}
+
+	while (sk->sk_state == TCP_SYN_SENT) {
+		DEFINE_WAIT(wait);
+
+		if (!timeo) {
+			err = -EINPROGRESS;
+			goto out;
+		}
+		if (signal_pending(tsk)) {
+			err = sock_intr_errno(timeo);
+			goto out;
+		}
+
+		prepare_to_wait_exclusive(sk_sleep(sk), &wait,
+						TASK_INTERRUPTIBLE);
+		release_sock(sk);
+		timeo = schedule_timeout(timeo);
+		lock_sock(sk);
+		finish_wait(sk_sleep(sk), &wait);
+	}
+
+	if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED))
+		err = 0;
+	else if (sk->sk_state == TCP_CLOSE_WAIT)
+		err = -ECONNRESET;
+	else
+		err = -ECONNREFUSED;
+	sock->state = err ? SS_UNCONNECTED : SS_CONNECTED;
+out:
+	release_sock(sk);
+	return err;
+}
+
+static int pn_socket_accept(struct socket *sock, struct socket *newsock,
+				int flags)
+{
+	struct sock *sk = sock->sk;
+	struct sock *newsk;
+	int err;
+
+	if (unlikely(sk->sk_state != TCP_LISTEN))
+		return -EINVAL;
+
+	newsk = sk->sk_prot->accept(sk, flags, &err);
+	if (!newsk)
+		return err;
+
+	lock_sock(newsk);
+	sock_graft(newsk, newsock);
+	newsock->state = SS_CONNECTED;
+	release_sock(newsk);
+	return 0;
+}
+
+static int pn_socket_getname(struct socket *sock, struct sockaddr *addr,
+				int *sockaddr_len, int peer)
+{
+	struct sock *sk = sock->sk;
+	struct pn_sock *pn = pn_sk(sk);
+
+	memset(addr, 0, sizeof(struct sockaddr_pn));
+	addr->sa_family = AF_PHONET;
+	if (!peer) /* Race with bind() here is userland's problem. */
+		pn_sockaddr_set_object((struct sockaddr_pn *)addr,
+					pn->sobject);
+
+	*sockaddr_len = sizeof(struct sockaddr_pn);
+	return 0;
+}
+
+static unsigned int pn_socket_poll(struct file *file, struct socket *sock,
+					poll_table *wait)
+{
+	struct sock *sk = sock->sk;
+	struct pep_sock *pn = pep_sk(sk);
+	unsigned int mask = 0;
+
+	poll_wait(file, sk_sleep(sk), wait);
+
+	if (sk->sk_state == TCP_CLOSE)
+		return POLLERR;
+	if (!skb_queue_empty(&sk->sk_receive_queue))
+		mask |= POLLIN | POLLRDNORM;
+	if (!skb_queue_empty(&pn->ctrlreq_queue))
+		mask |= POLLPRI;
+	if (!mask && sk->sk_state == TCP_CLOSE_WAIT)
+		return POLLHUP;
+
+	if (sk->sk_state == TCP_ESTABLISHED &&
+		atomic_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf &&
+		atomic_read(&pn->tx_credits))
+		mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
+
+	return mask;
+}
+
+static int pn_socket_ioctl(struct socket *sock, unsigned int cmd,
+				unsigned long arg)
+{
+	struct sock *sk = sock->sk;
+	struct pn_sock *pn = pn_sk(sk);
+
+	if (cmd == SIOCPNGETOBJECT) {
+		struct net_device *dev;
+		u16 handle;
+		u8 saddr;
+
+		if (get_user(handle, (__u16 __user *)arg))
+			return -EFAULT;
+
+		lock_sock(sk);
+		if (sk->sk_bound_dev_if)
+			dev = dev_get_by_index(sock_net(sk),
+						sk->sk_bound_dev_if);
+		else
+			dev = phonet_device_get(sock_net(sk));
+		if (dev && (dev->flags & IFF_UP))
+			saddr = phonet_address_get(dev, pn_addr(handle));
+		else
+			saddr = PN_NO_ADDR;
+		release_sock(sk);
+
+		if (dev)
+			dev_put(dev);
+		if (saddr == PN_NO_ADDR)
+			return -EHOSTUNREACH;
+
+		handle = pn_object(saddr, pn_port(pn->sobject));
+		return put_user(handle, (__u16 __user *)arg);
+	}
+
+	return sk->sk_prot->ioctl(sk, cmd, arg);
+}
+
+static int pn_socket_listen(struct socket *sock, int backlog)
+{
+	struct sock *sk = sock->sk;
+	int err = 0;
+
+	if (pn_socket_autobind(sock))
+		return -ENOBUFS;
+
+	lock_sock(sk);
+	if (sock->state != SS_UNCONNECTED) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	if (sk->sk_state != TCP_LISTEN) {
+		sk->sk_state = TCP_LISTEN;
+		sk->sk_ack_backlog = 0;
+	}
+	sk->sk_max_ack_backlog = backlog;
+out:
+	release_sock(sk);
+	return err;
+}
+
+static int pn_socket_sendmsg(struct socket *sock, struct msghdr *m,
+			     size_t total_len)
+{
+	struct sock *sk = sock->sk;
+
+	if (pn_socket_autobind(sock))
+		return -EAGAIN;
+
+	return sk->sk_prot->sendmsg(sk, m, total_len);
+}
+
+const struct proto_ops phonet_dgram_ops = {
+	.family		= AF_PHONET,
+	.owner		= THIS_MODULE,
+	.release	= pn_socket_release,
+	.bind		= pn_socket_bind,
+	.connect	= sock_no_connect,
+	.socketpair	= sock_no_socketpair,
+	.accept		= sock_no_accept,
+	.getname	= pn_socket_getname,
+	.poll		= datagram_poll,
+	.ioctl		= pn_socket_ioctl,
+	.listen		= sock_no_listen,
+	.shutdown	= sock_no_shutdown,
+	.setsockopt	= sock_no_setsockopt,
+	.getsockopt	= sock_no_getsockopt,
+#ifdef CONFIG_COMPAT
+	.compat_setsockopt = sock_no_setsockopt,
+	.compat_getsockopt = sock_no_getsockopt,
+#endif
+	.sendmsg	= pn_socket_sendmsg,
+	.recvmsg	= sock_common_recvmsg,
+	.mmap		= sock_no_mmap,
+	.sendpage	= sock_no_sendpage,
+};
+
+const struct proto_ops phonet_stream_ops = {
+	.family		= AF_PHONET,
+	.owner		= THIS_MODULE,
+	.release	= pn_socket_release,
+	.bind		= pn_socket_bind,
+	.connect	= pn_socket_connect,
+	.socketpair	= sock_no_socketpair,
+	.accept		= pn_socket_accept,
+	.getname	= pn_socket_getname,
+	.poll		= pn_socket_poll,
+	.ioctl		= pn_socket_ioctl,
+	.listen		= pn_socket_listen,
+	.shutdown	= sock_no_shutdown,
+	.setsockopt	= sock_common_setsockopt,
+	.getsockopt	= sock_common_getsockopt,
+#ifdef CONFIG_COMPAT
+	.compat_setsockopt = compat_sock_common_setsockopt,
+	.compat_getsockopt = compat_sock_common_getsockopt,
+#endif
+	.sendmsg	= pn_socket_sendmsg,
+	.recvmsg	= sock_common_recvmsg,
+	.mmap		= sock_no_mmap,
+	.sendpage	= sock_no_sendpage,
+};
+EXPORT_SYMBOL(phonet_stream_ops);
+
+/* allocate port for a socket */
+int pn_sock_get_port(struct sock *sk, unsigned short sport)
+{
+	static int port_cur;
+	struct net *net = sock_net(sk);
+	struct pn_sock *pn = pn_sk(sk);
+	struct sockaddr_pn try_sa;
+	struct sock *tmpsk;
+
+	memset(&try_sa, 0, sizeof(struct sockaddr_pn));
+	try_sa.spn_family = AF_PHONET;
+	WARN_ON(!mutex_is_locked(&port_mutex));
+	if (!sport) {
+		/* search free port */
+		int port, pmin, pmax;
+
+		phonet_get_local_port_range(&pmin, &pmax);
+		for (port = pmin; port <= pmax; port++) {
+			port_cur++;
+			if (port_cur < pmin || port_cur > pmax)
+				port_cur = pmin;
+
+			pn_sockaddr_set_port(&try_sa, port_cur);
+			tmpsk = pn_find_sock_by_sa(net, &try_sa);
+			if (tmpsk == NULL) {
+				sport = port_cur;
+				goto found;
+			} else
+				sock_put(tmpsk);
+		}
+	} else {
+		/* try to find specific port */
+		pn_sockaddr_set_port(&try_sa, sport);
+		tmpsk = pn_find_sock_by_sa(net, &try_sa);
+		if (tmpsk == NULL)
+			/* No sock there! We can use that port... */
+			goto found;
+		else
+			sock_put(tmpsk);
+	}
+	/* the port must be in use already */
+	return -EADDRINUSE;
+
+found:
+	pn->sobject = pn_object(pn_addr(pn->sobject), sport);
+	return 0;
+}
+EXPORT_SYMBOL(pn_sock_get_port);
+
+#ifdef CONFIG_PROC_FS
+static struct sock *pn_sock_get_idx(struct seq_file *seq, loff_t pos)
+{
+	struct net *net = seq_file_net(seq);
+	struct hlist_head *hlist = pnsocks.hlist;
+	struct sock *sknode;
+	unsigned int h;
+
+	for (h = 0; h < PN_HASHSIZE; h++) {
+		sk_for_each_rcu(sknode, hlist) {
+			if (!net_eq(net, sock_net(sknode)))
+				continue;
+			if (!pos)
+				return sknode;
+			pos--;
+		}
+		hlist++;
+	}
+	return NULL;
+}
+
+static struct sock *pn_sock_get_next(struct seq_file *seq, struct sock *sk)
+{
+	struct net *net = seq_file_net(seq);
+
+	do
+		sk = sk_next(sk);
+	while (sk && !net_eq(net, sock_net(sk)));
+
+	return sk;
+}
+
+static void *pn_sock_seq_start(struct seq_file *seq, loff_t *pos)
+	__acquires(rcu)
+{
+	rcu_read_lock();
+	return *pos ? pn_sock_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
+}
+
+static void *pn_sock_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct sock *sk;
+
+	if (v == SEQ_START_TOKEN)
+		sk = pn_sock_get_idx(seq, 0);
+	else
+		sk = pn_sock_get_next(seq, v);
+	(*pos)++;
+	return sk;
+}
+
+static void pn_sock_seq_stop(struct seq_file *seq, void *v)
+	__releases(rcu)
+{
+	rcu_read_unlock();
+}
+
+static int pn_sock_seq_show(struct seq_file *seq, void *v)
+{
+	seq_setwidth(seq, 127);
+	if (v == SEQ_START_TOKEN)
+		seq_puts(seq, "pt  loc  rem rs st tx_queue rx_queue "
+			"  uid inode ref pointer drops");
+	else {
+		struct sock *sk = v;
+		struct pn_sock *pn = pn_sk(sk);
+
+		seq_printf(seq, "%2d %04X:%04X:%02X %02X %08X:%08X %5d %lu "
+			"%d %pK %d",
+			sk->sk_protocol, pn->sobject, pn->dobject,
+			pn->resource, sk->sk_state,
+			sk_wmem_alloc_get(sk), sk_rmem_alloc_get(sk),
+			from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
+			sock_i_ino(sk),
+			atomic_read(&sk->sk_refcnt), sk,
+			atomic_read(&sk->sk_drops));
+	}
+	seq_pad(seq, '\n');
+	return 0;
+}
+
+static const struct seq_operations pn_sock_seq_ops = {
+	.start = pn_sock_seq_start,
+	.next = pn_sock_seq_next,
+	.stop = pn_sock_seq_stop,
+	.show = pn_sock_seq_show,
+};
+
+static int pn_sock_open(struct inode *inode, struct file *file)
+{
+	return seq_open_net(inode, file, &pn_sock_seq_ops,
+				sizeof(struct seq_net_private));
+}
+
+const struct file_operations pn_sock_seq_fops = {
+	.owner = THIS_MODULE,
+	.open = pn_sock_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = seq_release_net,
+};
+#endif
+
+static struct  {
+	struct sock *sk[256];
+} pnres;
+
+/*
+ * Find and hold socket based on resource.
+ */
+struct sock *pn_find_sock_by_res(struct net *net, u8 res)
+{
+	struct sock *sk;
+
+	if (!net_eq(net, &init_net))
+		return NULL;
+
+	rcu_read_lock();
+	sk = rcu_dereference(pnres.sk[res]);
+	if (sk)
+		sock_hold(sk);
+	rcu_read_unlock();
+	return sk;
+}
+
+static DEFINE_MUTEX(resource_mutex);
+
+int pn_sock_bind_res(struct sock *sk, u8 res)
+{
+	int ret = -EADDRINUSE;
+
+	if (!net_eq(sock_net(sk), &init_net))
+		return -ENOIOCTLCMD;
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+	if (pn_socket_autobind(sk->sk_socket))
+		return -EAGAIN;
+
+	mutex_lock(&resource_mutex);
+	if (pnres.sk[res] == NULL) {
+		sock_hold(sk);
+		rcu_assign_pointer(pnres.sk[res], sk);
+		ret = 0;
+	}
+	mutex_unlock(&resource_mutex);
+	return ret;
+}
+
+int pn_sock_unbind_res(struct sock *sk, u8 res)
+{
+	int ret = -ENOENT;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	mutex_lock(&resource_mutex);
+	if (pnres.sk[res] == sk) {
+		RCU_INIT_POINTER(pnres.sk[res], NULL);
+		ret = 0;
+	}
+	mutex_unlock(&resource_mutex);
+
+	if (ret == 0) {
+		synchronize_rcu();
+		sock_put(sk);
+	}
+	return ret;
+}
+
+void pn_sock_unbind_all_res(struct sock *sk)
+{
+	unsigned int res, match = 0;
+
+	mutex_lock(&resource_mutex);
+	for (res = 0; res < 256; res++) {
+		if (pnres.sk[res] == sk) {
+			RCU_INIT_POINTER(pnres.sk[res], NULL);
+			match++;
+		}
+	}
+	mutex_unlock(&resource_mutex);
+
+	while (match > 0) {
+		__sock_put(sk);
+		match--;
+	}
+	/* Caller is responsible for RCU sync before final sock_put() */
+}
+
+#ifdef CONFIG_PROC_FS
+static struct sock **pn_res_get_idx(struct seq_file *seq, loff_t pos)
+{
+	struct net *net = seq_file_net(seq);
+	unsigned int i;
+
+	if (!net_eq(net, &init_net))
+		return NULL;
+
+	for (i = 0; i < 256; i++) {
+		if (pnres.sk[i] == NULL)
+			continue;
+		if (!pos)
+			return pnres.sk + i;
+		pos--;
+	}
+	return NULL;
+}
+
+static struct sock **pn_res_get_next(struct seq_file *seq, struct sock **sk)
+{
+	struct net *net = seq_file_net(seq);
+	unsigned int i;
+
+	BUG_ON(!net_eq(net, &init_net));
+
+	for (i = (sk - pnres.sk) + 1; i < 256; i++)
+		if (pnres.sk[i])
+			return pnres.sk + i;
+	return NULL;
+}
+
+static void *pn_res_seq_start(struct seq_file *seq, loff_t *pos)
+	__acquires(resource_mutex)
+{
+	mutex_lock(&resource_mutex);
+	return *pos ? pn_res_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
+}
+
+static void *pn_res_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+	struct sock **sk;
+
+	if (v == SEQ_START_TOKEN)
+		sk = pn_res_get_idx(seq, 0);
+	else
+		sk = pn_res_get_next(seq, v);
+	(*pos)++;
+	return sk;
+}
+
+static void pn_res_seq_stop(struct seq_file *seq, void *v)
+	__releases(resource_mutex)
+{
+	mutex_unlock(&resource_mutex);
+}
+
+static int pn_res_seq_show(struct seq_file *seq, void *v)
+{
+	seq_setwidth(seq, 63);
+	if (v == SEQ_START_TOKEN)
+		seq_puts(seq, "rs   uid inode");
+	else {
+		struct sock **psk = v;
+		struct sock *sk = *psk;
+
+		seq_printf(seq, "%02X %5u %lu",
+			   (int) (psk - pnres.sk),
+			   from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
+			   sock_i_ino(sk));
+	}
+	seq_pad(seq, '\n');
+	return 0;
+}
+
+static const struct seq_operations pn_res_seq_ops = {
+	.start = pn_res_seq_start,
+	.next = pn_res_seq_next,
+	.stop = pn_res_seq_stop,
+	.show = pn_res_seq_show,
+};
+
+static int pn_res_open(struct inode *inode, struct file *file)
+{
+	return seq_open_net(inode, file, &pn_res_seq_ops,
+				sizeof(struct seq_net_private));
+}
+
+const struct file_operations pn_res_seq_fops = {
+	.owner = THIS_MODULE,
+	.open = pn_res_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = seq_release_net,
+};
+#endif