net: move ioctl functions into a separated file

They well deserve a separated unit.

Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 577 insertions, 574 deletions

diff --git a/net/core/Makefile b/net/core/Makefile
index 674641b13ae..0c5e3618c80 100644
--- a/net/core/Makefile
+++ b/net/core/Makefile
@@ -9,7 +9,7 @@ obj-$(CONFIG_SYSCTL) += sysctl_net_core.o
 
 obj-y		     += dev.o ethtool.o dev_addr_lists.o dst.o netevent.o \
 			neighbour.o rtnetlink.o utils.o link_watch.o filter.o \
-			sock_diag.o
+			sock_diag.o dev_ioctl.o
 
 obj-$(CONFIG_XFRM) += flow.o
 obj-y += net-sysfs.o
diff --git a/net/core/dev.c b/net/core/dev.c
index 6ad37896a32..1932d351ed7 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -106,7 +106,6 @@
 #include <net/xfrm.h>
 #include <linux/highmem.h>
 #include <linux/init.h>
-#include <linux/kmod.h>
 #include <linux/module.h>
 #include <linux/netpoll.h>
 #include <linux/rcupdate.h>
@@ -132,7 +131,6 @@
 #include <linux/pci.h>
 #include <linux/inetdevice.h>
 #include <linux/cpu_rmap.h>
-#include <linux/net_tstamp.h>
 #include <linux/static_key.h>
 
 #include "net-sysfs.h"
@@ -1226,36 +1224,6 @@ void netdev_notify_peers(struct net_device *dev)
 }
 EXPORT_SYMBOL(netdev_notify_peers);
 
-/**
- *	dev_load 	- load a network module
- *	@net: the applicable net namespace
- *	@name: name of interface
- *
- *	If a network interface is not present and the process has suitable
- *	privileges this function loads the module. If module loading is not
- *	available in this kernel then it becomes a nop.
- */
-
-void dev_load(struct net *net, const char *name)
-{
-	struct net_device *dev;
-	int no_module;
-
-	rcu_read_lock();
-	dev = dev_get_by_name_rcu(net, name);
-	rcu_read_unlock();
-
-	no_module = !dev;
-	if (no_module && capable(CAP_NET_ADMIN))
-		no_module = request_module("netdev-%s", name);
-	if (no_module && capable(CAP_SYS_MODULE)) {
-		if (!request_module("%s", name))
-			pr_warn("Loading kernel module for a network device with CAP_SYS_MODULE (deprecated).  Use CAP_NET_ADMIN and alias netdev-%s instead.\n",
-				name);
-	}
-}
-EXPORT_SYMBOL(dev_load);
-
 static int __dev_open(struct net_device *dev)
 {
 	const struct net_device_ops *ops = dev->netdev_ops;
@@ -1645,57 +1613,6 @@ static inline void net_timestamp_set(struct sk_buff *skb)
 			__net_timestamp(SKB);		\
 	}						\
 
-static int net_hwtstamp_validate(struct ifreq *ifr)
-{
-	struct hwtstamp_config cfg;
-	enum hwtstamp_tx_types tx_type;
-	enum hwtstamp_rx_filters rx_filter;
-	int tx_type_valid = 0;
-	int rx_filter_valid = 0;
-
-	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
-		return -EFAULT;
-
-	if (cfg.flags) /* reserved for future extensions */
-		return -EINVAL;
-
-	tx_type = cfg.tx_type;
-	rx_filter = cfg.rx_filter;
-
-	switch (tx_type) {
-	case HWTSTAMP_TX_OFF:
-	case HWTSTAMP_TX_ON:
-	case HWTSTAMP_TX_ONESTEP_SYNC:
-		tx_type_valid = 1;
-		break;
-	}
-
-	switch (rx_filter) {
-	case HWTSTAMP_FILTER_NONE:
-	case HWTSTAMP_FILTER_ALL:
-	case HWTSTAMP_FILTER_SOME:
-	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
-	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
-	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
-	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
-	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
-	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
-	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
-	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
-	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
-	case HWTSTAMP_FILTER_PTP_V2_EVENT:
-	case HWTSTAMP_FILTER_PTP_V2_SYNC:
-	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
-		rx_filter_valid = 1;
-		break;
-	}
-
-	if (!tx_type_valid || !rx_filter_valid)
-		return -ERANGE;
-
-	return 0;
-}
-
 static inline bool is_skb_forwardable(struct net_device *dev,
 				      struct sk_buff *skb)
 {
@@ -4300,127 +4217,6 @@ softnet_break:
 	goto out;
 }
 
-static gifconf_func_t *gifconf_list[NPROTO];
-
-/**
- *	register_gifconf	-	register a SIOCGIF handler
- *	@family: Address family
- *	@gifconf: Function handler
- *
- *	Register protocol dependent address dumping routines. The handler
- *	that is passed must not be freed or reused until it has been replaced
- *	by another handler.
- */
-int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
-{
-	if (family >= NPROTO)
-		return -EINVAL;
-	gifconf_list[family] = gifconf;
-	return 0;
-}
-EXPORT_SYMBOL(register_gifconf);
-
-
-/*
- *	Map an interface index to its name (SIOCGIFNAME)
- */
-
-/*
- *	We need this ioctl for efficient implementation of the
- *	if_indextoname() function required by the IPv6 API.  Without
- *	it, we would have to search all the interfaces to find a
- *	match.  --pb
- */
-
-static int dev_ifname(struct net *net, struct ifreq __user *arg)
-{
-	struct net_device *dev;
-	struct ifreq ifr;
-	unsigned seq;
-
-	/*
-	 *	Fetch the caller's info block.
-	 */
-
-	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
-		return -EFAULT;
-
-retry:
-	seq = read_seqcount_begin(&devnet_rename_seq);
-	rcu_read_lock();
-	dev = dev_get_by_index_rcu(net, ifr.ifr_ifindex);
-	if (!dev) {
-		rcu_read_unlock();
-		return -ENODEV;
-	}
-
-	strcpy(ifr.ifr_name, dev->name);
-	rcu_read_unlock();
-	if (read_seqcount_retry(&devnet_rename_seq, seq))
-		goto retry;
-
-	if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
-		return -EFAULT;
-	return 0;
-}
-
-/*
- *	Perform a SIOCGIFCONF call. This structure will change
- *	size eventually, and there is nothing I can do about it.
- *	Thus we will need a 'compatibility mode'.
- */
-
-static int dev_ifconf(struct net *net, char __user *arg)
-{
-	struct ifconf ifc;
-	struct net_device *dev;
-	char __user *pos;
-	int len;
-	int total;
-	int i;
-
-	/*
-	 *	Fetch the caller's info block.
-	 */
-
-	if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
-		return -EFAULT;
-
-	pos = ifc.ifc_buf;
-	len = ifc.ifc_len;
-
-	/*
-	 *	Loop over the interfaces, and write an info block for each.
-	 */
-
-	total = 0;
-	for_each_netdev(net, dev) {
-		for (i = 0; i < NPROTO; i++) {
-			if (gifconf_list[i]) {
-				int done;
-				if (!pos)
-					done = gifconf_list[i](dev, NULL, 0);
-				else
-					done = gifconf_list[i](dev, pos + total,
-							       len - total);
-				if (done < 0)
-					return -EFAULT;
-				total += done;
-			}
-		}
-	}
-
-	/*
-	 *	All done.  Write the updated control block back to the caller.
-	 */
-	ifc.ifc_len = total;
-
-	/*
-	 * 	Both BSD and Solaris return 0 here, so we do too.
-	 */
-	return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
-}
-
 #ifdef CONFIG_PROC_FS
 
 #define BUCKET_SPACE (32 - NETDEV_HASHBITS - 1)
@@ -5381,375 +5177,6 @@ int dev_change_carrier(struct net_device *dev, bool new_carrier)
 }
 EXPORT_SYMBOL(dev_change_carrier);
 
-/*
- *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
- */
-static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
-{
-	int err;
-	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
-
-	if (!dev)
-		return -ENODEV;
-
-	switch (cmd) {
-	case SIOCGIFFLAGS:	/* Get interface flags */
-		ifr->ifr_flags = (short) dev_get_flags(dev);
-		return 0;
-
-	case SIOCGIFMETRIC:	/* Get the metric on the interface
-				   (currently unused) */
-		ifr->ifr_metric = 0;
-		return 0;
-
-	case SIOCGIFMTU:	/* Get the MTU of a device */
-		ifr->ifr_mtu = dev->mtu;
-		return 0;
-
-	case SIOCGIFHWADDR:
-		if (!dev->addr_len)
-			memset(ifr->ifr_hwaddr.sa_data, 0, sizeof ifr->ifr_hwaddr.sa_data);
-		else
-			memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
-			       min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
-		ifr->ifr_hwaddr.sa_family = dev->type;
-		return 0;
-
-	case SIOCGIFSLAVE:
-		err = -EINVAL;
-		break;
-
-	case SIOCGIFMAP:
-		ifr->ifr_map.mem_start = dev->mem_start;
-		ifr->ifr_map.mem_end   = dev->mem_end;
-		ifr->ifr_map.base_addr = dev->base_addr;
-		ifr->ifr_map.irq       = dev->irq;
-		ifr->ifr_map.dma       = dev->dma;
-		ifr->ifr_map.port      = dev->if_port;
-		return 0;
-
-	case SIOCGIFINDEX:
-		ifr->ifr_ifindex = dev->ifindex;
-		return 0;
-
-	case SIOCGIFTXQLEN:
-		ifr->ifr_qlen = dev->tx_queue_len;
-		return 0;
-
-	default:
-		/* dev_ioctl() should ensure this case
-		 * is never reached
-		 */
-		WARN_ON(1);
-		err = -ENOTTY;
-		break;
-
-	}
-	return err;
-}
-
-/*
- *	Perform the SIOCxIFxxx calls, inside rtnl_lock()
- */
-static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
-{
-	int err;
-	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
-	const struct net_device_ops *ops;
-
-	if (!dev)
-		return -ENODEV;
-
-	ops = dev->netdev_ops;
-
-	switch (cmd) {
-	case SIOCSIFFLAGS:	/* Set interface flags */
-		return dev_change_flags(dev, ifr->ifr_flags);
-
-	case SIOCSIFMETRIC:	/* Set the metric on the interface
-				   (currently unused) */
-		return -EOPNOTSUPP;
-
-	case SIOCSIFMTU:	/* Set the MTU of a device */
-		return dev_set_mtu(dev, ifr->ifr_mtu);
-
-	case SIOCSIFHWADDR:
-		return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
-
-	case SIOCSIFHWBROADCAST:
-		if (ifr->ifr_hwaddr.sa_family != dev->type)
-			return -EINVAL;
-		memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
-		       min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
-		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
-		return 0;
-
-	case SIOCSIFMAP:
-		if (ops->ndo_set_config) {
-			if (!netif_device_present(dev))
-				return -ENODEV;
-			return ops->ndo_set_config(dev, &ifr->ifr_map);
-		}
-		return -EOPNOTSUPP;
-
-	case SIOCADDMULTI:
-		if (!ops->ndo_set_rx_mode ||
-		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
-			return -EINVAL;
-		if (!netif_device_present(dev))
-			return -ENODEV;
-		return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
-
-	case SIOCDELMULTI:
-		if (!ops->ndo_set_rx_mode ||
-		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
-			return -EINVAL;
-		if (!netif_device_present(dev))
-			return -ENODEV;
-		return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
-
-	case SIOCSIFTXQLEN:
-		if (ifr->ifr_qlen < 0)
-			return -EINVAL;
-		dev->tx_queue_len = ifr->ifr_qlen;
-		return 0;
-
-	case SIOCSIFNAME:
-		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
-		return dev_change_name(dev, ifr->ifr_newname);
-
-	case SIOCSHWTSTAMP:
-		err = net_hwtstamp_validate(ifr);
-		if (err)
-			return err;
-		/* fall through */
-
-	/*
-	 *	Unknown or private ioctl
-	 */
-	default:
-		if ((cmd >= SIOCDEVPRIVATE &&
-		    cmd <= SIOCDEVPRIVATE + 15) ||
-		    cmd == SIOCBONDENSLAVE ||
-		    cmd == SIOCBONDRELEASE ||
-		    cmd == SIOCBONDSETHWADDR ||
-		    cmd == SIOCBONDSLAVEINFOQUERY ||
-		    cmd == SIOCBONDINFOQUERY ||
-		    cmd == SIOCBONDCHANGEACTIVE ||
-		    cmd == SIOCGMIIPHY ||
-		    cmd == SIOCGMIIREG ||
-		    cmd == SIOCSMIIREG ||
-		    cmd == SIOCBRADDIF ||
-		    cmd == SIOCBRDELIF ||
-		    cmd == SIOCSHWTSTAMP ||
-		    cmd == SIOCWANDEV) {
-			err = -EOPNOTSUPP;
-			if (ops->ndo_do_ioctl) {
-				if (netif_device_present(dev))
-					err = ops->ndo_do_ioctl(dev, ifr, cmd);
-				else
-					err = -ENODEV;
-			}
-		} else
-			err = -EINVAL;
-
-	}
-	return err;
-}
-
-/*
- *	This function handles all "interface"-type I/O control requests. The actual
- *	'doing' part of this is dev_ifsioc above.
- */
-
-/**
- *	dev_ioctl	-	network device ioctl
- *	@net: the applicable net namespace
- *	@cmd: command to issue
- *	@arg: pointer to a struct ifreq in user space
- *
- *	Issue ioctl functions to devices. This is normally called by the
- *	user space syscall interfaces but can sometimes be useful for
- *	other purposes. The return value is the return from the syscall if
- *	positive or a negative errno code on error.
- */
-
-int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
-{
-	struct ifreq ifr;
-	int ret;
-	char *colon;
-
-	/* One special case: SIOCGIFCONF takes ifconf argument
-	   and requires shared lock, because it sleeps writing
-	   to user space.
-	 */
-
-	if (cmd == SIOCGIFCONF) {
-		rtnl_lock();
-		ret = dev_ifconf(net, (char __user *) arg);
-		rtnl_unlock();
-		return ret;
-	}
-	if (cmd == SIOCGIFNAME)
-		return dev_ifname(net, (struct ifreq __user *)arg);
-
-	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
-		return -EFAULT;
-
-	ifr.ifr_name[IFNAMSIZ-1] = 0;
-
-	colon = strchr(ifr.ifr_name, ':');
-	if (colon)
-		*colon = 0;
-
-	/*
-	 *	See which interface the caller is talking about.
-	 */
-
-	switch (cmd) {
-	/*
-	 *	These ioctl calls:
-	 *	- can be done by all.
-	 *	- atomic and do not require locking.
-	 *	- return a value
-	 */
-	case SIOCGIFFLAGS:
-	case SIOCGIFMETRIC:
-	case SIOCGIFMTU:
-	case SIOCGIFHWADDR:
-	case SIOCGIFSLAVE:
-	case SIOCGIFMAP:
-	case SIOCGIFINDEX:
-	case SIOCGIFTXQLEN:
-		dev_load(net, ifr.ifr_name);
-		rcu_read_lock();
-		ret = dev_ifsioc_locked(net, &ifr, cmd);
-		rcu_read_unlock();
-		if (!ret) {
-			if (colon)
-				*colon = ':';
-			if (copy_to_user(arg, &ifr,
-					 sizeof(struct ifreq)))
-				ret = -EFAULT;
-		}
-		return ret;
-
-	case SIOCETHTOOL:
-		dev_load(net, ifr.ifr_name);
-		rtnl_lock();
-		ret = dev_ethtool(net, &ifr);
-		rtnl_unlock();
-		if (!ret) {
-			if (colon)
-				*colon = ':';
-			if (copy_to_user(arg, &ifr,
-					 sizeof(struct ifreq)))
-				ret = -EFAULT;
-		}
-		return ret;
-
-	/*
-	 *	These ioctl calls:
-	 *	- require superuser power.
-	 *	- require strict serialization.
-	 *	- return a value
-	 */
-	case SIOCGMIIPHY:
-	case SIOCGMIIREG:
-	case SIOCSIFNAME:
-		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
-			return -EPERM;
-		dev_load(net, ifr.ifr_name);
-		rtnl_lock();
-		ret = dev_ifsioc(net, &ifr, cmd);
-		rtnl_unlock();
-		if (!ret) {
-			if (colon)
-				*colon = ':';
-			if (copy_to_user(arg, &ifr,
-					 sizeof(struct ifreq)))
-				ret = -EFAULT;
-		}
-		return ret;
-
-	/*
-	 *	These ioctl calls:
-	 *	- require superuser power.
-	 *	- require strict serialization.
-	 *	- do not return a value
-	 */
-	case SIOCSIFMAP:
-	case SIOCSIFTXQLEN:
-		if (!capable(CAP_NET_ADMIN))
-			return -EPERM;
-		/* fall through */
-	/*
-	 *	These ioctl calls:
-	 *	- require local superuser power.
-	 *	- require strict serialization.
-	 *	- do not return a value
-	 */
-	case SIOCSIFFLAGS:
-	case SIOCSIFMETRIC:
-	case SIOCSIFMTU:
-	case SIOCSIFHWADDR:
-	case SIOCSIFSLAVE:
-	case SIOCADDMULTI:
-	case SIOCDELMULTI:
-	case SIOCSIFHWBROADCAST:
-	case SIOCSMIIREG:
-	case SIOCBONDENSLAVE:
-	case SIOCBONDRELEASE:
-	case SIOCBONDSETHWADDR:
-	case SIOCBONDCHANGEACTIVE:
-	case SIOCBRADDIF:
-	case SIOCBRDELIF:
-	case SIOCSHWTSTAMP:
-		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
-			return -EPERM;
-		/* fall through */
-	case SIOCBONDSLAVEINFOQUERY:
-	case SIOCBONDINFOQUERY:
-		dev_load(net, ifr.ifr_name);
-		rtnl_lock();
-		ret = dev_ifsioc(net, &ifr, cmd);
-		rtnl_unlock();
-		return ret;
-
-	case SIOCGIFMEM:
-		/* Get the per device memory space. We can add this but
-		 * currently do not support it */
-	case SIOCSIFMEM:
-		/* Set the per device memory buffer space.
-		 * Not applicable in our case */
-	case SIOCSIFLINK:
-		return -ENOTTY;
-
-	/*
-	 *	Unknown or private ioctl.
-	 */
-	default:
-		if (cmd == SIOCWANDEV ||
-		    (cmd >= SIOCDEVPRIVATE &&
-		     cmd <= SIOCDEVPRIVATE + 15)) {
-			dev_load(net, ifr.ifr_name);
-			rtnl_lock();
-			ret = dev_ifsioc(net, &ifr, cmd);
-			rtnl_unlock();
-			if (!ret && copy_to_user(arg, &ifr,
-						 sizeof(struct ifreq)))
-				ret = -EFAULT;
-			return ret;
-		}
-		/* Take care of Wireless Extensions */
-		if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST)
-			return wext_handle_ioctl(net, &ifr, cmd, arg);
-		return -ENOTTY;
-	}
-}
-
-
 /**
  *	dev_new_index	-	allocate an ifindex
  *	@net: the applicable net namespace
diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c
new file mode 100644
index 00000000000..6cc0481faad
--- /dev/null
+++ b/net/core/dev_ioctl.c
@@ -0,0 +1,576 @@
+#include <linux/kmod.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/rtnetlink.h>
+#include <linux/net_tstamp.h>
+#include <linux/wireless.h>
+#include <net/wext.h>
+
+/*
+ *	Map an interface index to its name (SIOCGIFNAME)
+ */
+
+/*
+ *	We need this ioctl for efficient implementation of the
+ *	if_indextoname() function required by the IPv6 API.  Without
+ *	it, we would have to search all the interfaces to find a
+ *	match.  --pb
+ */
+
+static int dev_ifname(struct net *net, struct ifreq __user *arg)
+{
+	struct net_device *dev;
+	struct ifreq ifr;
+	unsigned seq;
+
+	/*
+	 *	Fetch the caller's info block.
+	 */
+
+	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
+		return -EFAULT;
+
+retry:
+	seq = read_seqcount_begin(&devnet_rename_seq);
+	rcu_read_lock();
+	dev = dev_get_by_index_rcu(net, ifr.ifr_ifindex);
+	if (!dev) {
+		rcu_read_unlock();
+		return -ENODEV;
+	}
+
+	strcpy(ifr.ifr_name, dev->name);
+	rcu_read_unlock();
+	if (read_seqcount_retry(&devnet_rename_seq, seq))
+		goto retry;
+
+	if (copy_to_user(arg, &ifr, sizeof(struct ifreq)))
+		return -EFAULT;
+	return 0;
+}
+
+static gifconf_func_t *gifconf_list[NPROTO];
+
+/**
+ *	register_gifconf	-	register a SIOCGIF handler
+ *	@family: Address family
+ *	@gifconf: Function handler
+ *
+ *	Register protocol dependent address dumping routines. The handler
+ *	that is passed must not be freed or reused until it has been replaced
+ *	by another handler.
+ */
+int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
+{
+	if (family >= NPROTO)
+		return -EINVAL;
+	gifconf_list[family] = gifconf;
+	return 0;
+}
+EXPORT_SYMBOL(register_gifconf);
+
+/*
+ *	Perform a SIOCGIFCONF call. This structure will change
+ *	size eventually, and there is nothing I can do about it.
+ *	Thus we will need a 'compatibility mode'.
+ */
+
+static int dev_ifconf(struct net *net, char __user *arg)
+{
+	struct ifconf ifc;
+	struct net_device *dev;
+	char __user *pos;
+	int len;
+	int total;
+	int i;
+
+	/*
+	 *	Fetch the caller's info block.
+	 */
+
+	if (copy_from_user(&ifc, arg, sizeof(struct ifconf)))
+		return -EFAULT;
+
+	pos = ifc.ifc_buf;
+	len = ifc.ifc_len;
+
+	/*
+	 *	Loop over the interfaces, and write an info block for each.
+	 */
+
+	total = 0;
+	for_each_netdev(net, dev) {
+		for (i = 0; i < NPROTO; i++) {
+			if (gifconf_list[i]) {
+				int done;
+				if (!pos)
+					done = gifconf_list[i](dev, NULL, 0);
+				else
+					done = gifconf_list[i](dev, pos + total,
+							       len - total);
+				if (done < 0)
+					return -EFAULT;
+				total += done;
+			}
+		}
+	}
+
+	/*
+	 *	All done.  Write the updated control block back to the caller.
+	 */
+	ifc.ifc_len = total;
+
+	/*
+	 * 	Both BSD and Solaris return 0 here, so we do too.
+	 */
+	return copy_to_user(arg, &ifc, sizeof(struct ifconf)) ? -EFAULT : 0;
+}
+
+/*
+ *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
+ */
+static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
+{
+	int err;
+	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
+
+	if (!dev)
+		return -ENODEV;
+
+	switch (cmd) {
+	case SIOCGIFFLAGS:	/* Get interface flags */
+		ifr->ifr_flags = (short) dev_get_flags(dev);
+		return 0;
+
+	case SIOCGIFMETRIC:	/* Get the metric on the interface
+				   (currently unused) */
+		ifr->ifr_metric = 0;
+		return 0;
+
+	case SIOCGIFMTU:	/* Get the MTU of a device */
+		ifr->ifr_mtu = dev->mtu;
+		return 0;
+
+	case SIOCGIFHWADDR:
+		if (!dev->addr_len)
+			memset(ifr->ifr_hwaddr.sa_data, 0, sizeof ifr->ifr_hwaddr.sa_data);
+		else
+			memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,
+			       min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
+		ifr->ifr_hwaddr.sa_family = dev->type;
+		return 0;
+
+	case SIOCGIFSLAVE:
+		err = -EINVAL;
+		break;
+
+	case SIOCGIFMAP:
+		ifr->ifr_map.mem_start = dev->mem_start;
+		ifr->ifr_map.mem_end   = dev->mem_end;
+		ifr->ifr_map.base_addr = dev->base_addr;
+		ifr->ifr_map.irq       = dev->irq;
+		ifr->ifr_map.dma       = dev->dma;
+		ifr->ifr_map.port      = dev->if_port;
+		return 0;
+
+	case SIOCGIFINDEX:
+		ifr->ifr_ifindex = dev->ifindex;
+		return 0;
+
+	case SIOCGIFTXQLEN:
+		ifr->ifr_qlen = dev->tx_queue_len;
+		return 0;
+
+	default:
+		/* dev_ioctl() should ensure this case
+		 * is never reached
+		 */
+		WARN_ON(1);
+		err = -ENOTTY;
+		break;
+
+	}
+	return err;
+}
+
+static int net_hwtstamp_validate(struct ifreq *ifr)
+{
+	struct hwtstamp_config cfg;
+	enum hwtstamp_tx_types tx_type;
+	enum hwtstamp_rx_filters rx_filter;
+	int tx_type_valid = 0;
+	int rx_filter_valid = 0;
+
+	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
+		return -EFAULT;
+
+	if (cfg.flags) /* reserved for future extensions */
+		return -EINVAL;
+
+	tx_type = cfg.tx_type;
+	rx_filter = cfg.rx_filter;
+
+	switch (tx_type) {
+	case HWTSTAMP_TX_OFF:
+	case HWTSTAMP_TX_ON:
+	case HWTSTAMP_TX_ONESTEP_SYNC:
+		tx_type_valid = 1;
+		break;
+	}
+
+	switch (rx_filter) {
+	case HWTSTAMP_FILTER_NONE:
+	case HWTSTAMP_FILTER_ALL:
+	case HWTSTAMP_FILTER_SOME:
+	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
+	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
+	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
+	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
+	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
+	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
+	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
+	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
+	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
+	case HWTSTAMP_FILTER_PTP_V2_EVENT:
+	case HWTSTAMP_FILTER_PTP_V2_SYNC:
+	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
+		rx_filter_valid = 1;
+		break;
+	}
+
+	if (!tx_type_valid || !rx_filter_valid)
+		return -ERANGE;
+
+	return 0;
+}
+
+/*
+ *	Perform the SIOCxIFxxx calls, inside rtnl_lock()
+ */
+static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd)
+{
+	int err;
+	struct net_device *dev = __dev_get_by_name(net, ifr->ifr_name);
+	const struct net_device_ops *ops;
+
+	if (!dev)
+		return -ENODEV;
+
+	ops = dev->netdev_ops;
+
+	switch (cmd) {
+	case SIOCSIFFLAGS:	/* Set interface flags */
+		return dev_change_flags(dev, ifr->ifr_flags);
+
+	case SIOCSIFMETRIC:	/* Set the metric on the interface
+				   (currently unused) */
+		return -EOPNOTSUPP;
+
+	case SIOCSIFMTU:	/* Set the MTU of a device */
+		return dev_set_mtu(dev, ifr->ifr_mtu);
+
+	case SIOCSIFHWADDR:
+		return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
+
+	case SIOCSIFHWBROADCAST:
+		if (ifr->ifr_hwaddr.sa_family != dev->type)
+			return -EINVAL;
+		memcpy(dev->broadcast, ifr->ifr_hwaddr.sa_data,
+		       min(sizeof ifr->ifr_hwaddr.sa_data, (size_t) dev->addr_len));
+		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
+		return 0;
+
+	case SIOCSIFMAP:
+		if (ops->ndo_set_config) {
+			if (!netif_device_present(dev))
+				return -ENODEV;
+			return ops->ndo_set_config(dev, &ifr->ifr_map);
+		}
+		return -EOPNOTSUPP;
+
+	case SIOCADDMULTI:
+		if (!ops->ndo_set_rx_mode ||
+		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
+			return -EINVAL;
+		if (!netif_device_present(dev))
+			return -ENODEV;
+		return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
+
+	case SIOCDELMULTI:
+		if (!ops->ndo_set_rx_mode ||
+		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
+			return -EINVAL;
+		if (!netif_device_present(dev))
+			return -ENODEV;
+		return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
+
+	case SIOCSIFTXQLEN:
+		if (ifr->ifr_qlen < 0)
+			return -EINVAL;
+		dev->tx_queue_len = ifr->ifr_qlen;
+		return 0;
+
+	case SIOCSIFNAME:
+		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
+		return dev_change_name(dev, ifr->ifr_newname);
+
+	case SIOCSHWTSTAMP:
+		err = net_hwtstamp_validate(ifr);
+		if (err)
+			return err;
+		/* fall through */
+
+	/*
+	 *	Unknown or private ioctl
+	 */
+	default:
+		if ((cmd >= SIOCDEVPRIVATE &&
+		    cmd <= SIOCDEVPRIVATE + 15) ||
+		    cmd == SIOCBONDENSLAVE ||
+		    cmd == SIOCBONDRELEASE ||
+		    cmd == SIOCBONDSETHWADDR ||
+		    cmd == SIOCBONDSLAVEINFOQUERY ||
+		    cmd == SIOCBONDINFOQUERY ||
+		    cmd == SIOCBONDCHANGEACTIVE ||
+		    cmd == SIOCGMIIPHY ||
+		    cmd == SIOCGMIIREG ||
+		    cmd == SIOCSMIIREG ||
+		    cmd == SIOCBRADDIF ||
+		    cmd == SIOCBRDELIF ||
+		    cmd == SIOCSHWTSTAMP ||
+		    cmd == SIOCWANDEV) {
+			err = -EOPNOTSUPP;
+			if (ops->ndo_do_ioctl) {
+				if (netif_device_present(dev))
+					err = ops->ndo_do_ioctl(dev, ifr, cmd);
+				else
+					err = -ENODEV;
+			}
+		} else
+			err = -EINVAL;
+
+	}
+	return err;
+}
+
+/**
+ *	dev_load 	- load a network module
+ *	@net: the applicable net namespace
+ *	@name: name of interface
+ *
+ *	If a network interface is not present and the process has suitable
+ *	privileges this function loads the module. If module loading is not
+ *	available in this kernel then it becomes a nop.
+ */
+
+void dev_load(struct net *net, const char *name)
+{
+	struct net_device *dev;
+	int no_module;
+
+	rcu_read_lock();
+	dev = dev_get_by_name_rcu(net, name);
+	rcu_read_unlock();
+
+	no_module = !dev;
+	if (no_module && capable(CAP_NET_ADMIN))
+		no_module = request_module("netdev-%s", name);
+	if (no_module && capable(CAP_SYS_MODULE)) {
+		if (!request_module("%s", name))
+			pr_warn("Loading kernel module for a network device with CAP_SYS_MODULE (deprecated).  Use CAP_NET_ADMIN and alias netdev-%s instead.\n",
+				name);
+	}
+}
+EXPORT_SYMBOL(dev_load);
+
+/*
+ *	This function handles all "interface"-type I/O control requests. The actual
+ *	'doing' part of this is dev_ifsioc above.
+ */
+
+/**
+ *	dev_ioctl	-	network device ioctl
+ *	@net: the applicable net namespace
+ *	@cmd: command to issue
+ *	@arg: pointer to a struct ifreq in user space
+ *
+ *	Issue ioctl functions to devices. This is normally called by the
+ *	user space syscall interfaces but can sometimes be useful for
+ *	other purposes. The return value is the return from the syscall if
+ *	positive or a negative errno code on error.
+ */
+
+int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
+{
+	struct ifreq ifr;
+	int ret;
+	char *colon;
+
+	/* One special case: SIOCGIFCONF takes ifconf argument
+	   and requires shared lock, because it sleeps writing
+	   to user space.
+	 */
+
+	if (cmd == SIOCGIFCONF) {
+		rtnl_lock();
+		ret = dev_ifconf(net, (char __user *) arg);
+		rtnl_unlock();
+		return ret;
+	}
+	if (cmd == SIOCGIFNAME)
+		return dev_ifname(net, (struct ifreq __user *)arg);
+
+	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
+		return -EFAULT;
+
+	ifr.ifr_name[IFNAMSIZ-1] = 0;
+
+	colon = strchr(ifr.ifr_name, ':');
+	if (colon)
+		*colon = 0;
+
+	/*
+	 *	See which interface the caller is talking about.
+	 */
+
+	switch (cmd) {
+	/*
+	 *	These ioctl calls:
+	 *	- can be done by all.
+	 *	- atomic and do not require locking.
+	 *	- return a value
+	 */
+	case SIOCGIFFLAGS:
+	case SIOCGIFMETRIC:
+	case SIOCGIFMTU:
+	case SIOCGIFHWADDR:
+	case SIOCGIFSLAVE:
+	case SIOCGIFMAP:
+	case SIOCGIFINDEX:
+	case SIOCGIFTXQLEN:
+		dev_load(net, ifr.ifr_name);
+		rcu_read_lock();
+		ret = dev_ifsioc_locked(net, &ifr, cmd);
+		rcu_read_unlock();
+		if (!ret) {
+			if (colon)
+				*colon = ':';
+			if (copy_to_user(arg, &ifr,
+					 sizeof(struct ifreq)))
+				ret = -EFAULT;
+		}
+		return ret;
+
+	case SIOCETHTOOL:
+		dev_load(net, ifr.ifr_name);
+		rtnl_lock();
+		ret = dev_ethtool(net, &ifr);
+		rtnl_unlock();
+		if (!ret) {
+			if (colon)
+				*colon = ':';
+			if (copy_to_user(arg, &ifr,
+					 sizeof(struct ifreq)))
+				ret = -EFAULT;
+		}
+		return ret;
+
+	/*
+	 *	These ioctl calls:
+	 *	- require superuser power.
+	 *	- require strict serialization.
+	 *	- return a value
+	 */
+	case SIOCGMIIPHY:
+	case SIOCGMIIREG:
+	case SIOCSIFNAME:
+		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
+			return -EPERM;
+		dev_load(net, ifr.ifr_name);
+		rtnl_lock();
+		ret = dev_ifsioc(net, &ifr, cmd);
+		rtnl_unlock();
+		if (!ret) {
+			if (colon)
+				*colon = ':';
+			if (copy_to_user(arg, &ifr,
+					 sizeof(struct ifreq)))
+				ret = -EFAULT;
+		}
+		return ret;
+
+	/*
+	 *	These ioctl calls:
+	 *	- require superuser power.
+	 *	- require strict serialization.
+	 *	- do not return a value
+	 */
+	case SIOCSIFMAP:
+	case SIOCSIFTXQLEN:
+		if (!capable(CAP_NET_ADMIN))
+			return -EPERM;
+		/* fall through */
+	/*
+	 *	These ioctl calls:
+	 *	- require local superuser power.
+	 *	- require strict serialization.
+	 *	- do not return a value
+	 */
+	case SIOCSIFFLAGS:
+	case SIOCSIFMETRIC:
+	case SIOCSIFMTU:
+	case SIOCSIFHWADDR:
+	case SIOCSIFSLAVE:
+	case SIOCADDMULTI:
+	case SIOCDELMULTI:
+	case SIOCSIFHWBROADCAST:
+	case SIOCSMIIREG:
+	case SIOCBONDENSLAVE:
+	case SIOCBONDRELEASE:
+	case SIOCBONDSETHWADDR:
+	case SIOCBONDCHANGEACTIVE:
+	case SIOCBRADDIF:
+	case SIOCBRDELIF:
+	case SIOCSHWTSTAMP:
+		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
+			return -EPERM;
+		/* fall through */
+	case SIOCBONDSLAVEINFOQUERY:
+	case SIOCBONDINFOQUERY:
+		dev_load(net, ifr.ifr_name);
+		rtnl_lock();
+		ret = dev_ifsioc(net, &ifr, cmd);
+		rtnl_unlock();
+		return ret;
+
+	case SIOCGIFMEM:
+		/* Get the per device memory space. We can add this but
+		 * currently do not support it */
+	case SIOCSIFMEM:
+		/* Set the per device memory buffer space.
+		 * Not applicable in our case */
+	case SIOCSIFLINK:
+		return -ENOTTY;
+
+	/*
+	 *	Unknown or private ioctl.
+	 */
+	default:
+		if (cmd == SIOCWANDEV ||
+		    (cmd >= SIOCDEVPRIVATE &&
+		     cmd <= SIOCDEVPRIVATE + 15)) {
+			dev_load(net, ifr.ifr_name);
+			rtnl_lock();
+			ret = dev_ifsioc(net, &ifr, cmd);
+			rtnl_unlock();
+			if (!ret && copy_to_user(arg, &ifr,
+						 sizeof(struct ifreq)))
+				ret = -EFAULT;
+			return ret;
+		}
+		/* Take care of Wireless Extensions */
+		if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST)
+			return wext_handle_ioctl(net, &ifr, cmd, arg);
+		return -ENOTTY;
+	}
+}