dev.c 158.1 KB
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/*
 * 	NET3	Protocol independent device support routines.
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 *	Derived from the non IP parts of dev.c 1.0.19
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 * 		Authors:	Ross Biro
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 *				Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *				Mark Evans, <evansmp@uhura.aston.ac.uk>
 *
 *	Additional Authors:
 *		Florian la Roche <rzsfl@rz.uni-sb.de>
 *		Alan Cox <gw4pts@gw4pts.ampr.org>
 *		David Hinds <dahinds@users.sourceforge.net>
 *		Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
 *		Adam Sulmicki <adam@cfar.umd.edu>
 *              Pekka Riikonen <priikone@poesidon.pspt.fi>
 *
 *	Changes:
 *              D.J. Barrow     :       Fixed bug where dev->refcnt gets set
 *              			to 2 if register_netdev gets called
 *              			before net_dev_init & also removed a
 *              			few lines of code in the process.
 *		Alan Cox	:	device private ioctl copies fields back.
 *		Alan Cox	:	Transmit queue code does relevant
 *					stunts to keep the queue safe.
 *		Alan Cox	:	Fixed double lock.
 *		Alan Cox	:	Fixed promisc NULL pointer trap
 *		????????	:	Support the full private ioctl range
 *		Alan Cox	:	Moved ioctl permission check into
 *					drivers
 *		Tim Kordas	:	SIOCADDMULTI/SIOCDELMULTI
 *		Alan Cox	:	100 backlog just doesn't cut it when
 *					you start doing multicast video 8)
 *		Alan Cox	:	Rewrote net_bh and list manager.
 *		Alan Cox	: 	Fix ETH_P_ALL echoback lengths.
 *		Alan Cox	:	Took out transmit every packet pass
 *					Saved a few bytes in the ioctl handler
 *		Alan Cox	:	Network driver sets packet type before
 *					calling netif_rx. Saves a function
 *					call a packet.
 *		Alan Cox	:	Hashed net_bh()
 *		Richard Kooijman:	Timestamp fixes.
 *		Alan Cox	:	Wrong field in SIOCGIFDSTADDR
 *		Alan Cox	:	Device lock protection.
 *		Alan Cox	: 	Fixed nasty side effect of device close
 *					changes.
 *		Rudi Cilibrasi	:	Pass the right thing to
 *					set_mac_address()
 *		Dave Miller	:	32bit quantity for the device lock to
 *					make it work out on a Sparc.
 *		Bjorn Ekwall	:	Added KERNELD hack.
 *		Alan Cox	:	Cleaned up the backlog initialise.
 *		Craig Metz	:	SIOCGIFCONF fix if space for under
 *					1 device.
 *	    Thomas Bogendoerfer :	Return ENODEV for dev_open, if there
 *					is no device open function.
 *		Andi Kleen	:	Fix error reporting for SIOCGIFCONF
 *	    Michael Chastain	:	Fix signed/unsigned for SIOCGIFCONF
 *		Cyrus Durgin	:	Cleaned for KMOD
 *		Adam Sulmicki   :	Bug Fix : Network Device Unload
 *					A network device unload needs to purge
 *					the backlog queue.
 *	Paul Rusty Russell	:	SIOCSIFNAME
 *              Pekka Riikonen  :	Netdev boot-time settings code
 *              Andrew Morton   :       Make unregister_netdevice wait
 *              			indefinitely on dev->refcnt
 * 		J Hadi Salim	:	- Backlog queue sampling
 *				        - netif_rx() feedback
 */

#include <asm/uaccess.h>
#include <asm/system.h>
#include <linux/bitops.h>
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#include <linux/capability.h>
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#include <linux/cpu.h>
#include <linux/types.h>
#include <linux/kernel.h>
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#include <linux/hash.h>
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#include <linux/slab.h>
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#include <linux/sched.h>
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#include <linux/mutex.h>
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#include <linux/string.h>
#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/if_ether.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
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#include <linux/ethtool.h>
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#include <linux/notifier.h>
#include <linux/skbuff.h>
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#include <net/net_namespace.h>
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#include <net/sock.h>
#include <linux/rtnetlink.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/stat.h>
#include <net/dst.h>
#include <net/pkt_sched.h>
#include <net/checksum.h>
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#include <net/xfrm.h>
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#include <linux/highmem.h>
#include <linux/init.h>
#include <linux/kmod.h>
#include <linux/module.h>
#include <linux/netpoll.h>
#include <linux/rcupdate.h>
#include <linux/delay.h>
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#include <net/wext.h>
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#include <net/iw_handler.h>
#include <asm/current.h>
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#include <linux/audit.h>
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#include <linux/dmaengine.h>
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#include <linux/err.h>
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#include <linux/ctype.h>
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#include <linux/if_arp.h>
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#include <linux/if_vlan.h>
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#include <linux/ip.h>
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#include <net/ip.h>
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#include <linux/ipv6.h>
#include <linux/in.h>
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#include <linux/jhash.h>
#include <linux/random.h>
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#include <trace/events/napi.h>
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#include <trace/events/net.h>
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#include <trace/events/skb.h>
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#include <linux/pci.h>
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#include <linux/inetdevice.h>
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#include <linux/cpu_rmap.h>
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#include "net-sysfs.h"

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/* Instead of increasing this, you should create a hash table. */
#define MAX_GRO_SKBS 8

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/* This should be increased if a protocol with a bigger head is added. */
#define GRO_MAX_HEAD (MAX_HEADER + 128)

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/*
 *	The list of packet types we will receive (as opposed to discard)
 *	and the routines to invoke.
 *
 *	Why 16. Because with 16 the only overlap we get on a hash of the
 *	low nibble of the protocol value is RARP/SNAP/X.25.
 *
 *      NOTE:  That is no longer true with the addition of VLAN tags.  Not
 *             sure which should go first, but I bet it won't make much
 *             difference if we are running VLANs.  The good news is that
 *             this protocol won't be in the list unless compiled in, so
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 *             the average user (w/out VLANs) will not be adversely affected.
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 *             --BLG
 *
 *		0800	IP
 *		8100    802.1Q VLAN
 *		0001	802.3
 *		0002	AX.25
 *		0004	802.2
 *		8035	RARP
 *		0005	SNAP
 *		0805	X.25
 *		0806	ARP
 *		8137	IPX
 *		0009	Localtalk
 *		86DD	IPv6
 */

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#define PTYPE_HASH_SIZE	(16)
#define PTYPE_HASH_MASK	(PTYPE_HASH_SIZE - 1)

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static DEFINE_SPINLOCK(ptype_lock);
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static struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
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static struct list_head ptype_all __read_mostly;	/* Taps */
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/*
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 * The @dev_base_head list is protected by @dev_base_lock and the rtnl
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 * semaphore.
 *
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 * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
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 *
 * Writers must hold the rtnl semaphore while they loop through the
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 * dev_base_head list, and hold dev_base_lock for writing when they do the
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 * actual updates.  This allows pure readers to access the list even
 * while a writer is preparing to update it.
 *
 * To put it another way, dev_base_lock is held for writing only to
 * protect against pure readers; the rtnl semaphore provides the
 * protection against other writers.
 *
 * See, for example usages, register_netdevice() and
 * unregister_netdevice(), which must be called with the rtnl
 * semaphore held.
 */
DEFINE_RWLOCK(dev_base_lock);
EXPORT_SYMBOL(dev_base_lock);

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static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
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{
	unsigned hash = full_name_hash(name, strnlen(name, IFNAMSIZ));
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	return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
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}

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static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
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{
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	return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
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}

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static inline void rps_lock(struct softnet_data *sd)
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{
#ifdef CONFIG_RPS
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	spin_lock(&sd->input_pkt_queue.lock);
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#endif
}

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static inline void rps_unlock(struct softnet_data *sd)
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{
#ifdef CONFIG_RPS
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	spin_unlock(&sd->input_pkt_queue.lock);
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#endif
}

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/* Device list insertion */
static int list_netdevice(struct net_device *dev)
{
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	struct net *net = dev_net(dev);
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	ASSERT_RTNL();

	write_lock_bh(&dev_base_lock);
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	list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
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	hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
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	hlist_add_head_rcu(&dev->index_hlist,
			   dev_index_hash(net, dev->ifindex));
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	write_unlock_bh(&dev_base_lock);
	return 0;
}

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/* Device list removal
 * caller must respect a RCU grace period before freeing/reusing dev
 */
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static void unlist_netdevice(struct net_device *dev)
{
	ASSERT_RTNL();

	/* Unlink dev from the device chain */
	write_lock_bh(&dev_base_lock);
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	list_del_rcu(&dev->dev_list);
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	hlist_del_rcu(&dev->name_hlist);
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	hlist_del_rcu(&dev->index_hlist);
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	write_unlock_bh(&dev_base_lock);
}

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/*
 *	Our notifier list
 */

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static RAW_NOTIFIER_HEAD(netdev_chain);
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/*
 *	Device drivers call our routines to queue packets here. We empty the
 *	queue in the local softnet handler.
 */
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DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
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EXPORT_PER_CPU_SYMBOL(softnet_data);
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#ifdef CONFIG_LOCKDEP
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/*
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 * register_netdevice() inits txq->_xmit_lock and sets lockdep class
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 * according to dev->type
 */
static const unsigned short netdev_lock_type[] =
	{ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
	 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
	 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
	 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
	 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
	 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
	 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
	 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
	 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
	 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
	 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
	 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
	 ARPHRD_FCFABRIC, ARPHRD_IEEE802_TR, ARPHRD_IEEE80211,
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	 ARPHRD_IEEE80211_PRISM, ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET,
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	 ARPHRD_PHONET_PIPE, ARPHRD_IEEE802154,
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	 ARPHRD_VOID, ARPHRD_NONE};
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static const char *const netdev_lock_name[] =
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	{"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
	 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
	 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
	 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
	 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
	 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
	 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
	 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
	 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
	 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
	 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
	 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
	 "_xmit_FCFABRIC", "_xmit_IEEE802_TR", "_xmit_IEEE80211",
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	 "_xmit_IEEE80211_PRISM", "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET",
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	 "_xmit_PHONET_PIPE", "_xmit_IEEE802154",
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	 "_xmit_VOID", "_xmit_NONE"};
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static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
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static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
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static inline unsigned short netdev_lock_pos(unsigned short dev_type)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
		if (netdev_lock_type[i] == dev_type)
			return i;
	/* the last key is used by default */
	return ARRAY_SIZE(netdev_lock_type) - 1;
}

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static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
						 unsigned short dev_type)
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{
	int i;

	i = netdev_lock_pos(dev_type);
	lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
				   netdev_lock_name[i]);
}
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static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
{
	int i;

	i = netdev_lock_pos(dev->type);
	lockdep_set_class_and_name(&dev->addr_list_lock,
				   &netdev_addr_lock_key[i],
				   netdev_lock_name[i]);
}
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#else
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static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
						 unsigned short dev_type)
{
}
static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
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{
}
#endif
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/*******************************************************************************

		Protocol management and registration routines

*******************************************************************************/

/*
 *	Add a protocol ID to the list. Now that the input handler is
 *	smarter we can dispense with all the messy stuff that used to be
 *	here.
 *
 *	BEWARE!!! Protocol handlers, mangling input packets,
 *	MUST BE last in hash buckets and checking protocol handlers
 *	MUST start from promiscuous ptype_all chain in net_bh.
 *	It is true now, do not change it.
 *	Explanation follows: if protocol handler, mangling packet, will
 *	be the first on list, it is not able to sense, that packet
 *	is cloned and should be copied-on-write, so that it will
 *	change it and subsequent readers will get broken packet.
 *							--ANK (980803)
 */

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static inline struct list_head *ptype_head(const struct packet_type *pt)
{
	if (pt->type == htons(ETH_P_ALL))
		return &ptype_all;
	else
		return &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
}

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/**
 *	dev_add_pack - add packet handler
 *	@pt: packet type declaration
 *
 *	Add a protocol handler to the networking stack. The passed &packet_type
 *	is linked into kernel lists and may not be freed until it has been
 *	removed from the kernel lists.
 *
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 *	This call does not sleep therefore it can not
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 *	guarantee all CPU's that are in middle of receiving packets
 *	will see the new packet type (until the next received packet).
 */

void dev_add_pack(struct packet_type *pt)
{
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	struct list_head *head = ptype_head(pt);
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	spin_lock(&ptype_lock);
	list_add_rcu(&pt->list, head);
	spin_unlock(&ptype_lock);
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}
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EXPORT_SYMBOL(dev_add_pack);
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/**
 *	__dev_remove_pack	 - remove packet handler
 *	@pt: packet type declaration
 *
 *	Remove a protocol handler that was previously added to the kernel
 *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
 *	from the kernel lists and can be freed or reused once this function
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 *	returns.
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 *
 *      The packet type might still be in use by receivers
 *	and must not be freed until after all the CPU's have gone
 *	through a quiescent state.
 */
void __dev_remove_pack(struct packet_type *pt)
{
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	struct list_head *head = ptype_head(pt);
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	struct packet_type *pt1;

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	spin_lock(&ptype_lock);
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	list_for_each_entry(pt1, head, list) {
		if (pt == pt1) {
			list_del_rcu(&pt->list);
			goto out;
		}
	}

	printk(KERN_WARNING "dev_remove_pack: %p not found.\n", pt);
out:
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	spin_unlock(&ptype_lock);
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}
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EXPORT_SYMBOL(__dev_remove_pack);

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/**
 *	dev_remove_pack	 - remove packet handler
 *	@pt: packet type declaration
 *
 *	Remove a protocol handler that was previously added to the kernel
 *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
 *	from the kernel lists and can be freed or reused once this function
 *	returns.
 *
 *	This call sleeps to guarantee that no CPU is looking at the packet
 *	type after return.
 */
void dev_remove_pack(struct packet_type *pt)
{
	__dev_remove_pack(pt);
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	synchronize_net();
}
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EXPORT_SYMBOL(dev_remove_pack);
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/******************************************************************************

		      Device Boot-time Settings Routines

*******************************************************************************/

/* Boot time configuration table */
static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];

/**
 *	netdev_boot_setup_add	- add new setup entry
 *	@name: name of the device
 *	@map: configured settings for the device
 *
 *	Adds new setup entry to the dev_boot_setup list.  The function
 *	returns 0 on error and 1 on success.  This is a generic routine to
 *	all netdevices.
 */
static int netdev_boot_setup_add(char *name, struct ifmap *map)
{
	struct netdev_boot_setup *s;
	int i;

	s = dev_boot_setup;
	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
		if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
			memset(s[i].name, 0, sizeof(s[i].name));
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			strlcpy(s[i].name, name, IFNAMSIZ);
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			memcpy(&s[i].map, map, sizeof(s[i].map));
			break;
		}
	}

	return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
}

/**
 *	netdev_boot_setup_check	- check boot time settings
 *	@dev: the netdevice
 *
 * 	Check boot time settings for the device.
 *	The found settings are set for the device to be used
 *	later in the device probing.
 *	Returns 0 if no settings found, 1 if they are.
 */
int netdev_boot_setup_check(struct net_device *dev)
{
	struct netdev_boot_setup *s = dev_boot_setup;
	int i;

	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
		if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
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		    !strcmp(dev->name, s[i].name)) {
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			dev->irq 	= s[i].map.irq;
			dev->base_addr 	= s[i].map.base_addr;
			dev->mem_start 	= s[i].map.mem_start;
			dev->mem_end 	= s[i].map.mem_end;
			return 1;
		}
	}
	return 0;
}
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EXPORT_SYMBOL(netdev_boot_setup_check);
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/**
 *	netdev_boot_base	- get address from boot time settings
 *	@prefix: prefix for network device
 *	@unit: id for network device
 *
 * 	Check boot time settings for the base address of device.
 *	The found settings are set for the device to be used
 *	later in the device probing.
 *	Returns 0 if no settings found.
 */
unsigned long netdev_boot_base(const char *prefix, int unit)
{
	const struct netdev_boot_setup *s = dev_boot_setup;
	char name[IFNAMSIZ];
	int i;

	sprintf(name, "%s%d", prefix, unit);

	/*
	 * If device already registered then return base of 1
	 * to indicate not to probe for this interface
	 */
549
	if (__dev_get_by_name(&init_net, name))
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		return 1;

	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
		if (!strcmp(name, s[i].name))
			return s[i].map.base_addr;
	return 0;
}

/*
 * Saves at boot time configured settings for any netdevice.
 */
int __init netdev_boot_setup(char *str)
{
	int ints[5];
	struct ifmap map;

	str = get_options(str, ARRAY_SIZE(ints), ints);
	if (!str || !*str)
		return 0;

	/* Save settings */
	memset(&map, 0, sizeof(map));
	if (ints[0] > 0)
		map.irq = ints[1];
	if (ints[0] > 1)
		map.base_addr = ints[2];
	if (ints[0] > 2)
		map.mem_start = ints[3];
	if (ints[0] > 3)
		map.mem_end = ints[4];

	/* Add new entry to the list */
	return netdev_boot_setup_add(str, &map);
}

__setup("netdev=", netdev_boot_setup);

/*******************************************************************************

			    Device Interface Subroutines

*******************************************************************************/

/**
 *	__dev_get_by_name	- find a device by its name
595
 *	@net: the applicable net namespace
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 *	@name: name to find
 *
 *	Find an interface by name. Must be called under RTNL semaphore
 *	or @dev_base_lock. If the name is found a pointer to the device
 *	is returned. If the name is not found then %NULL is returned. The
 *	reference counters are not incremented so the caller must be
 *	careful with locks.
 */

605
struct net_device *__dev_get_by_name(struct net *net, const char *name)
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{
	struct hlist_node *p;
E
Eric Dumazet 已提交
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	struct net_device *dev;
	struct hlist_head *head = dev_name_hash(net, name);
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E
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611
	hlist_for_each_entry(dev, p, head, name_hlist)
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		if (!strncmp(dev->name, name, IFNAMSIZ))
			return dev;
E
Eric Dumazet 已提交
614

L
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	return NULL;
}
E
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617
EXPORT_SYMBOL(__dev_get_by_name);
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619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644
/**
 *	dev_get_by_name_rcu	- find a device by its name
 *	@net: the applicable net namespace
 *	@name: name to find
 *
 *	Find an interface by name.
 *	If the name is found a pointer to the device is returned.
 * 	If the name is not found then %NULL is returned.
 *	The reference counters are not incremented so the caller must be
 *	careful with locks. The caller must hold RCU lock.
 */

struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
{
	struct hlist_node *p;
	struct net_device *dev;
	struct hlist_head *head = dev_name_hash(net, name);

	hlist_for_each_entry_rcu(dev, p, head, name_hlist)
		if (!strncmp(dev->name, name, IFNAMSIZ))
			return dev;

	return NULL;
}
EXPORT_SYMBOL(dev_get_by_name_rcu);

L
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645 646
/**
 *	dev_get_by_name		- find a device by its name
647
 *	@net: the applicable net namespace
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648 649 650 651 652 653 654 655 656
 *	@name: name to find
 *
 *	Find an interface by name. This can be called from any
 *	context and does its own locking. The returned handle has
 *	the usage count incremented and the caller must use dev_put() to
 *	release it when it is no longer needed. %NULL is returned if no
 *	matching device is found.
 */

657
struct net_device *dev_get_by_name(struct net *net, const char *name)
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{
	struct net_device *dev;

661 662
	rcu_read_lock();
	dev = dev_get_by_name_rcu(net, name);
L
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663 664
	if (dev)
		dev_hold(dev);
665
	rcu_read_unlock();
L
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	return dev;
}
E
Eric Dumazet 已提交
668
EXPORT_SYMBOL(dev_get_by_name);
L
Linus Torvalds 已提交
669 670 671

/**
 *	__dev_get_by_index - find a device by its ifindex
672
 *	@net: the applicable net namespace
L
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 *	@ifindex: index of device
 *
 *	Search for an interface by index. Returns %NULL if the device
 *	is not found or a pointer to the device. The device has not
 *	had its reference counter increased so the caller must be careful
 *	about locking. The caller must hold either the RTNL semaphore
 *	or @dev_base_lock.
 */

682
struct net_device *__dev_get_by_index(struct net *net, int ifindex)
L
Linus Torvalds 已提交
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{
	struct hlist_node *p;
E
Eric Dumazet 已提交
685 686
	struct net_device *dev;
	struct hlist_head *head = dev_index_hash(net, ifindex);
L
Linus Torvalds 已提交
687

E
Eric Dumazet 已提交
688
	hlist_for_each_entry(dev, p, head, index_hlist)
L
Linus Torvalds 已提交
689 690
		if (dev->ifindex == ifindex)
			return dev;
E
Eric Dumazet 已提交
691

L
Linus Torvalds 已提交
692 693
	return NULL;
}
E
Eric Dumazet 已提交
694
EXPORT_SYMBOL(__dev_get_by_index);
L
Linus Torvalds 已提交
695

696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720
/**
 *	dev_get_by_index_rcu - find a device by its ifindex
 *	@net: the applicable net namespace
 *	@ifindex: index of device
 *
 *	Search for an interface by index. Returns %NULL if the device
 *	is not found or a pointer to the device. The device has not
 *	had its reference counter increased so the caller must be careful
 *	about locking. The caller must hold RCU lock.
 */

struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
{
	struct hlist_node *p;
	struct net_device *dev;
	struct hlist_head *head = dev_index_hash(net, ifindex);

	hlist_for_each_entry_rcu(dev, p, head, index_hlist)
		if (dev->ifindex == ifindex)
			return dev;

	return NULL;
}
EXPORT_SYMBOL(dev_get_by_index_rcu);

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721 722 723

/**
 *	dev_get_by_index - find a device by its ifindex
724
 *	@net: the applicable net namespace
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725 726 727 728 729 730 731 732
 *	@ifindex: index of device
 *
 *	Search for an interface by index. Returns NULL if the device
 *	is not found or a pointer to the device. The device returned has
 *	had a reference added and the pointer is safe until the user calls
 *	dev_put to indicate they have finished with it.
 */

733
struct net_device *dev_get_by_index(struct net *net, int ifindex)
L
Linus Torvalds 已提交
734 735 736
{
	struct net_device *dev;

737 738
	rcu_read_lock();
	dev = dev_get_by_index_rcu(net, ifindex);
L
Linus Torvalds 已提交
739 740
	if (dev)
		dev_hold(dev);
741
	rcu_read_unlock();
L
Linus Torvalds 已提交
742 743
	return dev;
}
E
Eric Dumazet 已提交
744
EXPORT_SYMBOL(dev_get_by_index);
L
Linus Torvalds 已提交
745 746

/**
747
 *	dev_getbyhwaddr_rcu - find a device by its hardware address
748
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
749 750 751 752
 *	@type: media type of device
 *	@ha: hardware address
 *
 *	Search for an interface by MAC address. Returns NULL if the device
E
Eric Dumazet 已提交
753 754
 *	is not found or a pointer to the device.
 *	The caller must hold RCU or RTNL.
755
 *	The returned device has not had its ref count increased
L
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756 757 758 759
 *	and the caller must therefore be careful about locking
 *
 */

760 761
struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
				       const char *ha)
L
Linus Torvalds 已提交
762 763 764
{
	struct net_device *dev;

765
	for_each_netdev_rcu(net, dev)
L
Linus Torvalds 已提交
766 767
		if (dev->type == type &&
		    !memcmp(dev->dev_addr, ha, dev->addr_len))
768 769 770
			return dev;

	return NULL;
L
Linus Torvalds 已提交
771
}
772
EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
773

774
struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
L
Linus Torvalds 已提交
775 776 777
{
	struct net_device *dev;

778
	ASSERT_RTNL();
779
	for_each_netdev(net, dev)
780
		if (dev->type == type)
781 782 783
			return dev;

	return NULL;
784 785 786
}
EXPORT_SYMBOL(__dev_getfirstbyhwtype);

787
struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
788
{
789
	struct net_device *dev, *ret = NULL;
790

791 792 793 794 795 796 797 798 799
	rcu_read_lock();
	for_each_netdev_rcu(net, dev)
		if (dev->type == type) {
			dev_hold(dev);
			ret = dev;
			break;
		}
	rcu_read_unlock();
	return ret;
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800 801 802 803
}
EXPORT_SYMBOL(dev_getfirstbyhwtype);

/**
E
Eric Dumazet 已提交
804
 *	dev_get_by_flags_rcu - find any device with given flags
805
 *	@net: the applicable net namespace
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806 807 808 809
 *	@if_flags: IFF_* values
 *	@mask: bitmask of bits in if_flags to check
 *
 *	Search for any interface with the given flags. Returns NULL if a device
E
Eric Dumazet 已提交
810 811
 *	is not found or a pointer to the device. Must be called inside
 *	rcu_read_lock(), and result refcount is unchanged.
L
Linus Torvalds 已提交
812 813
 */

E
Eric Dumazet 已提交
814
struct net_device *dev_get_by_flags_rcu(struct net *net, unsigned short if_flags,
E
Eric Dumazet 已提交
815
				    unsigned short mask)
L
Linus Torvalds 已提交
816
{
817
	struct net_device *dev, *ret;
L
Linus Torvalds 已提交
818

819
	ret = NULL;
820
	for_each_netdev_rcu(net, dev) {
L
Linus Torvalds 已提交
821
		if (((dev->flags ^ if_flags) & mask) == 0) {
822
			ret = dev;
L
Linus Torvalds 已提交
823 824 825
			break;
		}
	}
826
	return ret;
L
Linus Torvalds 已提交
827
}
E
Eric Dumazet 已提交
828
EXPORT_SYMBOL(dev_get_by_flags_rcu);
L
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829 830 831 832 833 834

/**
 *	dev_valid_name - check if name is okay for network device
 *	@name: name string
 *
 *	Network device names need to be valid file names to
835 836
 *	to allow sysfs to work.  We also disallow any kind of
 *	whitespace.
L
Linus Torvalds 已提交
837
 */
838
int dev_valid_name(const char *name)
L
Linus Torvalds 已提交
839
{
840 841
	if (*name == '\0')
		return 0;
842 843
	if (strlen(name) >= IFNAMSIZ)
		return 0;
844 845 846 847 848 849 850 851 852
	if (!strcmp(name, ".") || !strcmp(name, ".."))
		return 0;

	while (*name) {
		if (*name == '/' || isspace(*name))
			return 0;
		name++;
	}
	return 1;
L
Linus Torvalds 已提交
853
}
E
Eric Dumazet 已提交
854
EXPORT_SYMBOL(dev_valid_name);
L
Linus Torvalds 已提交
855 856

/**
857 858
 *	__dev_alloc_name - allocate a name for a device
 *	@net: network namespace to allocate the device name in
L
Linus Torvalds 已提交
859
 *	@name: name format string
860
 *	@buf:  scratch buffer and result name string
L
Linus Torvalds 已提交
861 862
 *
 *	Passed a format string - eg "lt%d" it will try and find a suitable
S
Stephen Hemminger 已提交
863 864 865 866 867 868
 *	id. It scans list of devices to build up a free map, then chooses
 *	the first empty slot. The caller must hold the dev_base or rtnl lock
 *	while allocating the name and adding the device in order to avoid
 *	duplicates.
 *	Limited to bits_per_byte * page size devices (ie 32K on most platforms).
 *	Returns the number of the unit assigned or a negative errno code.
L
Linus Torvalds 已提交
869 870
 */

871
static int __dev_alloc_name(struct net *net, const char *name, char *buf)
L
Linus Torvalds 已提交
872 873 874 875
{
	int i = 0;
	const char *p;
	const int max_netdevices = 8*PAGE_SIZE;
S
Stephen Hemminger 已提交
876
	unsigned long *inuse;
L
Linus Torvalds 已提交
877 878 879 880 881 882 883 884 885 886 887 888 889
	struct net_device *d;

	p = strnchr(name, IFNAMSIZ-1, '%');
	if (p) {
		/*
		 * Verify the string as this thing may have come from
		 * the user.  There must be either one "%d" and no other "%"
		 * characters.
		 */
		if (p[1] != 'd' || strchr(p + 2, '%'))
			return -EINVAL;

		/* Use one page as a bit array of possible slots */
S
Stephen Hemminger 已提交
890
		inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
L
Linus Torvalds 已提交
891 892 893
		if (!inuse)
			return -ENOMEM;

894
		for_each_netdev(net, d) {
L
Linus Torvalds 已提交
895 896 897 898 899 900
			if (!sscanf(d->name, name, &i))
				continue;
			if (i < 0 || i >= max_netdevices)
				continue;

			/*  avoid cases where sscanf is not exact inverse of printf */
901
			snprintf(buf, IFNAMSIZ, name, i);
L
Linus Torvalds 已提交
902 903 904 905 906 907 908 909
			if (!strncmp(buf, d->name, IFNAMSIZ))
				set_bit(i, inuse);
		}

		i = find_first_zero_bit(inuse, max_netdevices);
		free_page((unsigned long) inuse);
	}

910 911
	if (buf != name)
		snprintf(buf, IFNAMSIZ, name, i);
912
	if (!__dev_get_by_name(net, buf))
L
Linus Torvalds 已提交
913 914 915 916 917 918 919 920 921
		return i;

	/* It is possible to run out of possible slots
	 * when the name is long and there isn't enough space left
	 * for the digits, or if all bits are used.
	 */
	return -ENFILE;
}

922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941
/**
 *	dev_alloc_name - allocate a name for a device
 *	@dev: device
 *	@name: name format string
 *
 *	Passed a format string - eg "lt%d" it will try and find a suitable
 *	id. It scans list of devices to build up a free map, then chooses
 *	the first empty slot. The caller must hold the dev_base or rtnl lock
 *	while allocating the name and adding the device in order to avoid
 *	duplicates.
 *	Limited to bits_per_byte * page size devices (ie 32K on most platforms).
 *	Returns the number of the unit assigned or a negative errno code.
 */

int dev_alloc_name(struct net_device *dev, const char *name)
{
	char buf[IFNAMSIZ];
	struct net *net;
	int ret;

942 943
	BUG_ON(!dev_net(dev));
	net = dev_net(dev);
944 945 946 947 948
	ret = __dev_alloc_name(net, name, buf);
	if (ret >= 0)
		strlcpy(dev->name, buf, IFNAMSIZ);
	return ret;
}
E
Eric Dumazet 已提交
949
EXPORT_SYMBOL(dev_alloc_name);
950

951
static int dev_get_valid_name(struct net_device *dev, const char *name)
952
{
953 954 955 956 957
	struct net *net;

	BUG_ON(!dev_net(dev));
	net = dev_net(dev);

958 959 960
	if (!dev_valid_name(name))
		return -EINVAL;

961
	if (strchr(name, '%'))
962
		return dev_alloc_name(dev, name);
963 964
	else if (__dev_get_by_name(net, name))
		return -EEXIST;
965 966
	else if (dev->name != name)
		strlcpy(dev->name, name, IFNAMSIZ);
967 968 969

	return 0;
}
L
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970 971 972 973 974 975 976 977 978

/**
 *	dev_change_name - change name of a device
 *	@dev: device
 *	@newname: name (or format string) must be at least IFNAMSIZ
 *
 *	Change name of a device, can pass format strings "eth%d".
 *	for wildcarding.
 */
979
int dev_change_name(struct net_device *dev, const char *newname)
L
Linus Torvalds 已提交
980
{
981
	char oldname[IFNAMSIZ];
L
Linus Torvalds 已提交
982
	int err = 0;
983
	int ret;
984
	struct net *net;
L
Linus Torvalds 已提交
985 986

	ASSERT_RTNL();
987
	BUG_ON(!dev_net(dev));
L
Linus Torvalds 已提交
988

989
	net = dev_net(dev);
L
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990 991 992
	if (dev->flags & IFF_UP)
		return -EBUSY;

993 994 995
	if (strncmp(newname, dev->name, IFNAMSIZ) == 0)
		return 0;

996 997
	memcpy(oldname, dev->name, IFNAMSIZ);

998
	err = dev_get_valid_name(dev, newname);
999 1000
	if (err < 0)
		return err;
L
Linus Torvalds 已提交
1001

1002
rollback:
1003 1004 1005 1006
	ret = device_rename(&dev->dev, dev->name);
	if (ret) {
		memcpy(dev->name, oldname, IFNAMSIZ);
		return ret;
1007
	}
1008 1009

	write_lock_bh(&dev_base_lock);
1010
	hlist_del_rcu(&dev->name_hlist);
1011 1012 1013 1014 1015 1016
	write_unlock_bh(&dev_base_lock);

	synchronize_rcu();

	write_lock_bh(&dev_base_lock);
	hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
1017 1018
	write_unlock_bh(&dev_base_lock);

1019
	ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1020 1021 1022
	ret = notifier_to_errno(ret);

	if (ret) {
1023 1024
		/* err >= 0 after dev_alloc_name() or stores the first errno */
		if (err >= 0) {
1025 1026 1027
			err = ret;
			memcpy(dev->name, oldname, IFNAMSIZ);
			goto rollback;
1028 1029 1030 1031
		} else {
			printk(KERN_ERR
			       "%s: name change rollback failed: %d.\n",
			       dev->name, ret);
1032 1033
		}
	}
L
Linus Torvalds 已提交
1034 1035 1036 1037

	return err;
}

1038 1039 1040 1041
/**
 *	dev_set_alias - change ifalias of a device
 *	@dev: device
 *	@alias: name up to IFALIASZ
1042
 *	@len: limit of bytes to copy from info
1043 1044 1045 1046 1047 1048 1049 1050 1051 1052
 *
 *	Set ifalias for a device,
 */
int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
{
	ASSERT_RTNL();

	if (len >= IFALIASZ)
		return -EINVAL;

1053 1054 1055 1056 1057 1058 1059 1060
	if (!len) {
		if (dev->ifalias) {
			kfree(dev->ifalias);
			dev->ifalias = NULL;
		}
		return 0;
	}

E
Eric Dumazet 已提交
1061
	dev->ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
1062 1063 1064 1065 1066 1067 1068 1069
	if (!dev->ifalias)
		return -ENOMEM;

	strlcpy(dev->ifalias, alias, len+1);
	return len;
}


1070
/**
S
Stephen Hemminger 已提交
1071
 *	netdev_features_change - device changes features
1072 1073 1074 1075 1076 1077
 *	@dev: device to cause notification
 *
 *	Called to indicate a device has changed features.
 */
void netdev_features_change(struct net_device *dev)
{
1078
	call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1079 1080 1081
}
EXPORT_SYMBOL(netdev_features_change);

L
Linus Torvalds 已提交
1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092
/**
 *	netdev_state_change - device changes state
 *	@dev: device to cause notification
 *
 *	Called to indicate a device has changed state. This function calls
 *	the notifier chains for netdev_chain and sends a NEWLINK message
 *	to the routing socket.
 */
void netdev_state_change(struct net_device *dev)
{
	if (dev->flags & IFF_UP) {
1093
		call_netdevice_notifiers(NETDEV_CHANGE, dev);
L
Linus Torvalds 已提交
1094 1095 1096
		rtmsg_ifinfo(RTM_NEWLINK, dev, 0);
	}
}
E
Eric Dumazet 已提交
1097
EXPORT_SYMBOL(netdev_state_change);
L
Linus Torvalds 已提交
1098

1099
int netdev_bonding_change(struct net_device *dev, unsigned long event)
1100
{
1101
	return call_netdevice_notifiers(event, dev);
1102 1103 1104
}
EXPORT_SYMBOL(netdev_bonding_change);

L
Linus Torvalds 已提交
1105 1106
/**
 *	dev_load 	- load a network module
1107
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
1108 1109 1110 1111 1112 1113 1114
 *	@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.
 */

1115
void dev_load(struct net *net, const char *name)
L
Linus Torvalds 已提交
1116
{
1117
	struct net_device *dev;
1118
	int no_module;
L
Linus Torvalds 已提交
1119

1120 1121 1122
	rcu_read_lock();
	dev = dev_get_by_name_rcu(net, name);
	rcu_read_unlock();
L
Linus Torvalds 已提交
1123

1124 1125 1126 1127 1128 1129 1130 1131 1132
	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_err("Loading kernel module for a network device "
"with CAP_SYS_MODULE (deprecated).  Use CAP_NET_ADMIN and alias netdev-%s "
"instead\n", name);
	}
L
Linus Torvalds 已提交
1133
}
E
Eric Dumazet 已提交
1134
EXPORT_SYMBOL(dev_load);
L
Linus Torvalds 已提交
1135

1136
static int __dev_open(struct net_device *dev)
L
Linus Torvalds 已提交
1137
{
1138
	const struct net_device_ops *ops = dev->netdev_ops;
1139
	int ret;
L
Linus Torvalds 已提交
1140

1141 1142
	ASSERT_RTNL();

L
Linus Torvalds 已提交
1143 1144 1145
	if (!netif_device_present(dev))
		return -ENODEV;

1146 1147 1148 1149 1150
	ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
	ret = notifier_to_errno(ret);
	if (ret)
		return ret;

L
Linus Torvalds 已提交
1151
	set_bit(__LINK_STATE_START, &dev->state);
1152

1153 1154
	if (ops->ndo_validate_addr)
		ret = ops->ndo_validate_addr(dev);
1155

1156 1157
	if (!ret && ops->ndo_open)
		ret = ops->ndo_open(dev);
L
Linus Torvalds 已提交
1158

1159 1160 1161
	if (ret)
		clear_bit(__LINK_STATE_START, &dev->state);
	else {
L
Linus Torvalds 已提交
1162
		dev->flags |= IFF_UP;
1163
		net_dmaengine_get();
1164
		dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
1165 1166
		dev_activate(dev);
	}
1167

L
Linus Torvalds 已提交
1168 1169 1170 1171
	return ret;
}

/**
1172 1173
 *	dev_open	- prepare an interface for use.
 *	@dev:	device to open
L
Linus Torvalds 已提交
1174
 *
1175 1176 1177 1178 1179 1180 1181
 *	Takes a device from down to up state. The device's private open
 *	function is invoked and then the multicast lists are loaded. Finally
 *	the device is moved into the up state and a %NETDEV_UP message is
 *	sent to the netdev notifier chain.
 *
 *	Calling this function on an active interface is a nop. On a failure
 *	a negative errno code is returned.
L
Linus Torvalds 已提交
1182
 */
1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200
int dev_open(struct net_device *dev)
{
	int ret;

	if (dev->flags & IFF_UP)
		return 0;

	ret = __dev_open(dev);
	if (ret < 0)
		return ret;

	rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
	call_netdevice_notifiers(NETDEV_UP, dev);

	return ret;
}
EXPORT_SYMBOL(dev_open);

1201
static int __dev_close_many(struct list_head *head)
L
Linus Torvalds 已提交
1202
{
1203
	struct net_device *dev;
1204

1205
	ASSERT_RTNL();
1206 1207
	might_sleep();

1208 1209
	list_for_each_entry(dev, head, unreg_list) {
		call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
L
Linus Torvalds 已提交
1210

1211
		clear_bit(__LINK_STATE_START, &dev->state);
L
Linus Torvalds 已提交
1212

1213 1214 1215 1216 1217 1218 1219 1220
		/* Synchronize to scheduled poll. We cannot touch poll list, it
		 * can be even on different cpu. So just clear netif_running().
		 *
		 * dev->stop() will invoke napi_disable() on all of it's
		 * napi_struct instances on this device.
		 */
		smp_mb__after_clear_bit(); /* Commit netif_running(). */
	}
L
Linus Torvalds 已提交
1221

1222
	dev_deactivate_many(head);
1223

1224 1225
	list_for_each_entry(dev, head, unreg_list) {
		const struct net_device_ops *ops = dev->netdev_ops;
L
Linus Torvalds 已提交
1226

1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245
		/*
		 *	Call the device specific close. This cannot fail.
		 *	Only if device is UP
		 *
		 *	We allow it to be called even after a DETACH hot-plug
		 *	event.
		 */
		if (ops->ndo_stop)
			ops->ndo_stop(dev);

		dev->flags &= ~IFF_UP;
		net_dmaengine_put();
	}

	return 0;
}

static int __dev_close(struct net_device *dev)
{
1246
	int retval;
1247 1248 1249
	LIST_HEAD(single);

	list_add(&dev->unreg_list, &single);
1250 1251 1252
	retval = __dev_close_many(&single);
	list_del(&single);
	return retval;
1253 1254
}

E
Eric Dumazet 已提交
1255
static int dev_close_many(struct list_head *head)
1256 1257 1258
{
	struct net_device *dev, *tmp;
	LIST_HEAD(tmp_list);
L
Linus Torvalds 已提交
1259

1260 1261 1262 1263 1264
	list_for_each_entry_safe(dev, tmp, head, unreg_list)
		if (!(dev->flags & IFF_UP))
			list_move(&dev->unreg_list, &tmp_list);

	__dev_close_many(head);
L
Linus Torvalds 已提交
1265

1266 1267 1268 1269
	list_for_each_entry(dev, head, unreg_list) {
		rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING);
		call_netdevice_notifiers(NETDEV_DOWN, dev);
	}
1270

1271 1272
	/* rollback_registered_many needs the complete original list */
	list_splice(&tmp_list, head);
1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286
	return 0;
}

/**
 *	dev_close - shutdown an interface.
 *	@dev: device to shutdown
 *
 *	This function moves an active device into down state. A
 *	%NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
 *	is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
 *	chain.
 */
int dev_close(struct net_device *dev)
{
1287 1288
	if (dev->flags & IFF_UP) {
		LIST_HEAD(single);
L
Linus Torvalds 已提交
1289

1290 1291 1292 1293
		list_add(&dev->unreg_list, &single);
		dev_close_many(&single);
		list_del(&single);
	}
L
Linus Torvalds 已提交
1294 1295
	return 0;
}
E
Eric Dumazet 已提交
1296
EXPORT_SYMBOL(dev_close);
L
Linus Torvalds 已提交
1297 1298


1299 1300 1301 1302 1303 1304 1305 1306 1307 1308
/**
 *	dev_disable_lro - disable Large Receive Offload on a device
 *	@dev: device
 *
 *	Disable Large Receive Offload (LRO) on a net device.  Must be
 *	called under RTNL.  This is needed if received packets may be
 *	forwarded to another interface.
 */
void dev_disable_lro(struct net_device *dev)
{
1309 1310
	u32 flags;

1311 1312 1313 1314 1315 1316 1317
	/*
	 * If we're trying to disable lro on a vlan device
	 * use the underlying physical device instead
	 */
	if (is_vlan_dev(dev))
		dev = vlan_dev_real_dev(dev);

1318 1319 1320 1321 1322 1323 1324 1325 1326
	if (dev->ethtool_ops && dev->ethtool_ops->get_flags)
		flags = dev->ethtool_ops->get_flags(dev);
	else
		flags = ethtool_op_get_flags(dev);

	if (!(flags & ETH_FLAG_LRO))
		return;

	__ethtool_set_flags(dev, flags & ~ETH_FLAG_LRO);
1327 1328
	if (unlikely(dev->features & NETIF_F_LRO))
		netdev_WARN(dev, "failed to disable LRO!\n");
1329 1330 1331 1332
}
EXPORT_SYMBOL(dev_disable_lro);


1333 1334
static int dev_boot_phase = 1;

L
Linus Torvalds 已提交
1335 1336 1337 1338 1339 1340 1341 1342 1343 1344
/**
 *	register_netdevice_notifier - register a network notifier block
 *	@nb: notifier
 *
 *	Register a notifier to be called when network device events occur.
 *	The notifier passed is linked into the kernel structures and must
 *	not be reused until it has been unregistered. A negative errno code
 *	is returned on a failure.
 *
 * 	When registered all registration and up events are replayed
1345
 *	to the new notifier to allow device to have a race free
L
Linus Torvalds 已提交
1346 1347 1348 1349 1350 1351
 *	view of the network device list.
 */

int register_netdevice_notifier(struct notifier_block *nb)
{
	struct net_device *dev;
1352
	struct net_device *last;
1353
	struct net *net;
L
Linus Torvalds 已提交
1354 1355 1356
	int err;

	rtnl_lock();
1357
	err = raw_notifier_chain_register(&netdev_chain, nb);
1358 1359
	if (err)
		goto unlock;
1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370
	if (dev_boot_phase)
		goto unlock;
	for_each_net(net) {
		for_each_netdev(net, dev) {
			err = nb->notifier_call(nb, NETDEV_REGISTER, dev);
			err = notifier_to_errno(err);
			if (err)
				goto rollback;

			if (!(dev->flags & IFF_UP))
				continue;
L
Linus Torvalds 已提交
1371

1372 1373
			nb->notifier_call(nb, NETDEV_UP, dev);
		}
L
Linus Torvalds 已提交
1374
	}
1375 1376

unlock:
L
Linus Torvalds 已提交
1377 1378
	rtnl_unlock();
	return err;
1379 1380 1381

rollback:
	last = dev;
1382 1383 1384 1385
	for_each_net(net) {
		for_each_netdev(net, dev) {
			if (dev == last)
				break;
1386

1387 1388 1389 1390 1391
			if (dev->flags & IFF_UP) {
				nb->notifier_call(nb, NETDEV_GOING_DOWN, dev);
				nb->notifier_call(nb, NETDEV_DOWN, dev);
			}
			nb->notifier_call(nb, NETDEV_UNREGISTER, dev);
1392
			nb->notifier_call(nb, NETDEV_UNREGISTER_BATCH, dev);
1393 1394
		}
	}
1395 1396

	raw_notifier_chain_unregister(&netdev_chain, nb);
1397
	goto unlock;
L
Linus Torvalds 已提交
1398
}
E
Eric Dumazet 已提交
1399
EXPORT_SYMBOL(register_netdevice_notifier);
L
Linus Torvalds 已提交
1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412

/**
 *	unregister_netdevice_notifier - unregister a network notifier block
 *	@nb: notifier
 *
 *	Unregister a notifier previously registered by
 *	register_netdevice_notifier(). The notifier is unlinked into the
 *	kernel structures and may then be reused. A negative errno code
 *	is returned on a failure.
 */

int unregister_netdevice_notifier(struct notifier_block *nb)
{
1413 1414 1415
	int err;

	rtnl_lock();
1416
	err = raw_notifier_chain_unregister(&netdev_chain, nb);
1417 1418
	rtnl_unlock();
	return err;
L
Linus Torvalds 已提交
1419
}
E
Eric Dumazet 已提交
1420
EXPORT_SYMBOL(unregister_netdevice_notifier);
L
Linus Torvalds 已提交
1421 1422 1423 1424

/**
 *	call_netdevice_notifiers - call all network notifier blocks
 *      @val: value passed unmodified to notifier function
1425
 *      @dev: net_device pointer passed unmodified to notifier function
L
Linus Torvalds 已提交
1426 1427
 *
 *	Call all network notifier blocks.  Parameters and return value
1428
 *	are as for raw_notifier_call_chain().
L
Linus Torvalds 已提交
1429 1430
 */

1431
int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
L
Linus Torvalds 已提交
1432
{
1433
	ASSERT_RTNL();
1434
	return raw_notifier_call_chain(&netdev_chain, val, dev);
L
Linus Torvalds 已提交
1435
}
1436
EXPORT_SYMBOL(call_netdevice_notifiers);
L
Linus Torvalds 已提交
1437 1438 1439 1440 1441 1442 1443 1444

/* When > 0 there are consumers of rx skb time stamps */
static atomic_t netstamp_needed = ATOMIC_INIT(0);

void net_enable_timestamp(void)
{
	atomic_inc(&netstamp_needed);
}
E
Eric Dumazet 已提交
1445
EXPORT_SYMBOL(net_enable_timestamp);
L
Linus Torvalds 已提交
1446 1447 1448 1449 1450

void net_disable_timestamp(void)
{
	atomic_dec(&netstamp_needed);
}
E
Eric Dumazet 已提交
1451
EXPORT_SYMBOL(net_disable_timestamp);
L
Linus Torvalds 已提交
1452

E
Eric Dumazet 已提交
1453
static inline void net_timestamp_set(struct sk_buff *skb)
L
Linus Torvalds 已提交
1454 1455
{
	if (atomic_read(&netstamp_needed))
1456
		__net_timestamp(skb);
1457 1458
	else
		skb->tstamp.tv64 = 0;
L
Linus Torvalds 已提交
1459 1460
}

E
Eric Dumazet 已提交
1461 1462 1463 1464 1465 1466
static inline void net_timestamp_check(struct sk_buff *skb)
{
	if (!skb->tstamp.tv64 && atomic_read(&netstamp_needed))
		__net_timestamp(skb);
}

1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487
static inline bool is_skb_forwardable(struct net_device *dev,
				      struct sk_buff *skb)
{
	unsigned int len;

	if (!(dev->flags & IFF_UP))
		return false;

	len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
	if (skb->len <= len)
		return true;

	/* if TSO is enabled, we don't care about the length as the packet
	 * could be forwarded without being segmented before
	 */
	if (skb_is_gso(skb))
		return true;

	return false;
}

1488 1489 1490 1491 1492 1493 1494 1495
/**
 * dev_forward_skb - loopback an skb to another netif
 *
 * @dev: destination network device
 * @skb: buffer to forward
 *
 * return values:
 *	NET_RX_SUCCESS	(no congestion)
1496
 *	NET_RX_DROP     (packet was dropped, but freed)
1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508
 *
 * dev_forward_skb can be used for injecting an skb from the
 * start_xmit function of one device into the receive queue
 * of another device.
 *
 * The receiving device may be in another namespace, so
 * we have to clear all information in the skb that could
 * impact namespace isolation.
 */
int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
{
	skb_orphan(skb);
1509
	nf_reset(skb);
1510

1511
	if (unlikely(!is_skb_forwardable(dev, skb))) {
1512
		atomic_long_inc(&dev->rx_dropped);
1513
		kfree_skb(skb);
1514
		return NET_RX_DROP;
1515
	}
1516
	skb_set_dev(skb, dev);
1517 1518 1519 1520 1521 1522 1523
	skb->tstamp.tv64 = 0;
	skb->pkt_type = PACKET_HOST;
	skb->protocol = eth_type_trans(skb, dev);
	return netif_rx(skb);
}
EXPORT_SYMBOL_GPL(dev_forward_skb);

1524 1525 1526 1527 1528 1529 1530 1531
static inline int deliver_skb(struct sk_buff *skb,
			      struct packet_type *pt_prev,
			      struct net_device *orig_dev)
{
	atomic_inc(&skb->users);
	return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
}

L
Linus Torvalds 已提交
1532 1533 1534 1535 1536
/*
 *	Support routine. Sends outgoing frames to any network
 *	taps currently in use.
 */

1537
static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
L
Linus Torvalds 已提交
1538 1539
{
	struct packet_type *ptype;
1540 1541
	struct sk_buff *skb2 = NULL;
	struct packet_type *pt_prev = NULL;
1542

L
Linus Torvalds 已提交
1543 1544 1545 1546 1547 1548 1549 1550
	rcu_read_lock();
	list_for_each_entry_rcu(ptype, &ptype_all, list) {
		/* Never send packets back to the socket
		 * they originated from - MvS (miquels@drinkel.ow.org)
		 */
		if ((ptype->dev == dev || !ptype->dev) &&
		    (ptype->af_packet_priv == NULL ||
		     (struct sock *)ptype->af_packet_priv != skb->sk)) {
1551 1552 1553 1554 1555 1556 1557
			if (pt_prev) {
				deliver_skb(skb2, pt_prev, skb->dev);
				pt_prev = ptype;
				continue;
			}

			skb2 = skb_clone(skb, GFP_ATOMIC);
L
Linus Torvalds 已提交
1558 1559 1560
			if (!skb2)
				break;

1561 1562
			net_timestamp_set(skb2);

L
Linus Torvalds 已提交
1563 1564 1565 1566
			/* skb->nh should be correctly
			   set by sender, so that the second statement is
			   just protection against buggy protocols.
			 */
1567
			skb_reset_mac_header(skb2);
L
Linus Torvalds 已提交
1568

1569
			if (skb_network_header(skb2) < skb2->data ||
1570
			    skb2->network_header > skb2->tail) {
L
Linus Torvalds 已提交
1571 1572 1573
				if (net_ratelimit())
					printk(KERN_CRIT "protocol %04x is "
					       "buggy, dev %s\n",
1574 1575
					       ntohs(skb2->protocol),
					       dev->name);
1576
				skb_reset_network_header(skb2);
L
Linus Torvalds 已提交
1577 1578
			}

1579
			skb2->transport_header = skb2->network_header;
L
Linus Torvalds 已提交
1580
			skb2->pkt_type = PACKET_OUTGOING;
1581
			pt_prev = ptype;
L
Linus Torvalds 已提交
1582 1583
		}
	}
1584 1585
	if (pt_prev)
		pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
L
Linus Torvalds 已提交
1586 1587 1588
	rcu_read_unlock();
}

1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600
/* netif_setup_tc - Handle tc mappings on real_num_tx_queues change
 * @dev: Network device
 * @txq: number of queues available
 *
 * If real_num_tx_queues is changed the tc mappings may no longer be
 * valid. To resolve this verify the tc mapping remains valid and if
 * not NULL the mapping. With no priorities mapping to this
 * offset/count pair it will no longer be used. In the worst case TC0
 * is invalid nothing can be done so disable priority mappings. If is
 * expected that drivers will fix this mapping if they can before
 * calling netif_set_real_num_tx_queues.
 */
E
Eric Dumazet 已提交
1601
static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630
{
	int i;
	struct netdev_tc_txq *tc = &dev->tc_to_txq[0];

	/* If TC0 is invalidated disable TC mapping */
	if (tc->offset + tc->count > txq) {
		pr_warning("Number of in use tx queues changed "
			   "invalidating tc mappings. Priority "
			   "traffic classification disabled!\n");
		dev->num_tc = 0;
		return;
	}

	/* Invalidated prio to tc mappings set to TC0 */
	for (i = 1; i < TC_BITMASK + 1; i++) {
		int q = netdev_get_prio_tc_map(dev, i);

		tc = &dev->tc_to_txq[q];
		if (tc->offset + tc->count > txq) {
			pr_warning("Number of in use tx queues "
				   "changed. Priority %i to tc "
				   "mapping %i is no longer valid "
				   "setting map to 0\n",
				   i, q);
			netdev_set_prio_tc_map(dev, i, 0);
		}
	}
}

1631 1632 1633 1634
/*
 * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
 * greater then real_num_tx_queues stale skbs on the qdisc must be flushed.
 */
1635
int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
1636
{
T
Tom Herbert 已提交
1637 1638
	int rc;

1639 1640
	if (txq < 1 || txq > dev->num_tx_queues)
		return -EINVAL;
1641

1642 1643
	if (dev->reg_state == NETREG_REGISTERED ||
	    dev->reg_state == NETREG_UNREGISTERING) {
1644 1645
		ASSERT_RTNL();

T
Tom Herbert 已提交
1646 1647
		rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
						  txq);
T
Tom Herbert 已提交
1648 1649 1650
		if (rc)
			return rc;

1651 1652 1653
		if (dev->num_tc)
			netif_setup_tc(dev, txq);

1654 1655
		if (txq < dev->real_num_tx_queues)
			qdisc_reset_all_tx_gt(dev, txq);
1656
	}
1657 1658 1659

	dev->real_num_tx_queues = txq;
	return 0;
1660 1661
}
EXPORT_SYMBOL(netif_set_real_num_tx_queues);
1662

1663 1664 1665 1666 1667 1668 1669 1670
#ifdef CONFIG_RPS
/**
 *	netif_set_real_num_rx_queues - set actual number of RX queues used
 *	@dev: Network device
 *	@rxq: Actual number of RX queues
 *
 *	This must be called either with the rtnl_lock held or before
 *	registration of the net device.  Returns 0 on success, or a
1671 1672
 *	negative error code.  If called before registration, it always
 *	succeeds.
1673 1674 1675 1676 1677
 */
int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
{
	int rc;

T
Tom Herbert 已提交
1678 1679 1680
	if (rxq < 1 || rxq > dev->num_rx_queues)
		return -EINVAL;

1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695
	if (dev->reg_state == NETREG_REGISTERED) {
		ASSERT_RTNL();

		rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
						  rxq);
		if (rc)
			return rc;
	}

	dev->real_num_rx_queues = rxq;
	return 0;
}
EXPORT_SYMBOL(netif_set_real_num_rx_queues);
#endif

1696
static inline void __netif_reschedule(struct Qdisc *q)
1697
{
1698 1699
	struct softnet_data *sd;
	unsigned long flags;
1700

1701 1702
	local_irq_save(flags);
	sd = &__get_cpu_var(softnet_data);
1703 1704 1705
	q->next_sched = NULL;
	*sd->output_queue_tailp = q;
	sd->output_queue_tailp = &q->next_sched;
1706 1707 1708 1709 1710 1711 1712 1713
	raise_softirq_irqoff(NET_TX_SOFTIRQ);
	local_irq_restore(flags);
}

void __netif_schedule(struct Qdisc *q)
{
	if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
		__netif_reschedule(q);
1714 1715 1716
}
EXPORT_SYMBOL(__netif_schedule);

1717
void dev_kfree_skb_irq(struct sk_buff *skb)
1718
{
1719
	if (atomic_dec_and_test(&skb->users)) {
1720 1721
		struct softnet_data *sd;
		unsigned long flags;
1722

1723 1724 1725 1726 1727 1728 1729
		local_irq_save(flags);
		sd = &__get_cpu_var(softnet_data);
		skb->next = sd->completion_queue;
		sd->completion_queue = skb;
		raise_softirq_irqoff(NET_TX_SOFTIRQ);
		local_irq_restore(flags);
	}
1730
}
1731
EXPORT_SYMBOL(dev_kfree_skb_irq);
1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742

void dev_kfree_skb_any(struct sk_buff *skb)
{
	if (in_irq() || irqs_disabled())
		dev_kfree_skb_irq(skb);
	else
		dev_kfree_skb(skb);
}
EXPORT_SYMBOL(dev_kfree_skb_any);


1743 1744 1745 1746 1747 1748
/**
 * netif_device_detach - mark device as removed
 * @dev: network device
 *
 * Mark device as removed from system and therefore no longer available.
 */
1749 1750 1751 1752
void netif_device_detach(struct net_device *dev)
{
	if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
	    netif_running(dev)) {
1753
		netif_tx_stop_all_queues(dev);
1754 1755 1756 1757
	}
}
EXPORT_SYMBOL(netif_device_detach);

1758 1759 1760 1761 1762 1763
/**
 * netif_device_attach - mark device as attached
 * @dev: network device
 *
 * Mark device as attached from system and restart if needed.
 */
1764 1765 1766 1767
void netif_device_attach(struct net_device *dev)
{
	if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
	    netif_running(dev)) {
1768
		netif_tx_wake_all_queues(dev);
1769
		__netdev_watchdog_up(dev);
1770 1771 1772 1773
	}
}
EXPORT_SYMBOL(netif_device_attach);

1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803
/**
 * skb_dev_set -- assign a new device to a buffer
 * @skb: buffer for the new device
 * @dev: network device
 *
 * If an skb is owned by a device already, we have to reset
 * all data private to the namespace a device belongs to
 * before assigning it a new device.
 */
#ifdef CONFIG_NET_NS
void skb_set_dev(struct sk_buff *skb, struct net_device *dev)
{
	skb_dst_drop(skb);
	if (skb->dev && !net_eq(dev_net(skb->dev), dev_net(dev))) {
		secpath_reset(skb);
		nf_reset(skb);
		skb_init_secmark(skb);
		skb->mark = 0;
		skb->priority = 0;
		skb->nf_trace = 0;
		skb->ipvs_property = 0;
#ifdef CONFIG_NET_SCHED
		skb->tc_index = 0;
#endif
	}
	skb->dev = dev;
}
EXPORT_SYMBOL(skb_set_dev);
#endif /* CONFIG_NET_NS */

L
Linus Torvalds 已提交
1804 1805 1806 1807
/*
 * Invalidate hardware checksum when packet is to be mangled, and
 * complete checksum manually on outgoing path.
 */
1808
int skb_checksum_help(struct sk_buff *skb)
L
Linus Torvalds 已提交
1809
{
1810
	__wsum csum;
1811
	int ret = 0, offset;
L
Linus Torvalds 已提交
1812

1813
	if (skb->ip_summed == CHECKSUM_COMPLETE)
1814 1815 1816 1817 1818
		goto out_set_summed;

	if (unlikely(skb_shinfo(skb)->gso_size)) {
		/* Let GSO fix up the checksum. */
		goto out_set_summed;
L
Linus Torvalds 已提交
1819 1820
	}

1821
	offset = skb_checksum_start_offset(skb);
1822 1823 1824 1825 1826 1827 1828 1829
	BUG_ON(offset >= skb_headlen(skb));
	csum = skb_checksum(skb, offset, skb->len - offset, 0);

	offset += skb->csum_offset;
	BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));

	if (skb_cloned(skb) &&
	    !skb_clone_writable(skb, offset + sizeof(__sum16))) {
L
Linus Torvalds 已提交
1830 1831 1832 1833 1834
		ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
		if (ret)
			goto out;
	}

1835
	*(__sum16 *)(skb->data + offset) = csum_fold(csum);
1836
out_set_summed:
L
Linus Torvalds 已提交
1837
	skb->ip_summed = CHECKSUM_NONE;
1838
out:
L
Linus Torvalds 已提交
1839 1840
	return ret;
}
E
Eric Dumazet 已提交
1841
EXPORT_SYMBOL(skb_checksum_help);
L
Linus Torvalds 已提交
1842

1843 1844 1845
/**
 *	skb_gso_segment - Perform segmentation on skb.
 *	@skb: buffer to segment
1846
 *	@features: features for the output path (see dev->features)
1847 1848
 *
 *	This function segments the given skb and returns a list of segments.
1849 1850 1851
 *
 *	It may return NULL if the skb requires no segmentation.  This is
 *	only possible when GSO is used for verifying header integrity.
1852
 */
1853
struct sk_buff *skb_gso_segment(struct sk_buff *skb, u32 features)
1854 1855 1856
{
	struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
	struct packet_type *ptype;
A
Al Viro 已提交
1857
	__be16 type = skb->protocol;
1858
	int vlan_depth = ETH_HLEN;
1859
	int err;
1860

1861 1862
	while (type == htons(ETH_P_8021Q)) {
		struct vlan_hdr *vh;
1863

1864
		if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN)))
1865 1866
			return ERR_PTR(-EINVAL);

1867 1868 1869
		vh = (struct vlan_hdr *)(skb->data + vlan_depth);
		type = vh->h_vlan_encapsulated_proto;
		vlan_depth += VLAN_HLEN;
1870 1871
	}

1872
	skb_reset_mac_header(skb);
1873
	skb->mac_len = skb->network_header - skb->mac_header;
1874 1875
	__skb_pull(skb, skb->mac_len);

1876 1877 1878 1879 1880 1881 1882
	if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
		struct net_device *dev = skb->dev;
		struct ethtool_drvinfo info = {};

		if (dev && dev->ethtool_ops && dev->ethtool_ops->get_drvinfo)
			dev->ethtool_ops->get_drvinfo(dev, &info);

J
Joe Perches 已提交
1883
		WARN(1, "%s: caps=(0x%lx, 0x%lx) len=%d data_len=%d ip_summed=%d\n",
1884 1885 1886 1887
		     info.driver, dev ? dev->features : 0L,
		     skb->sk ? skb->sk->sk_route_caps : 0L,
		     skb->len, skb->data_len, skb->ip_summed);

1888 1889 1890 1891 1892
		if (skb_header_cloned(skb) &&
		    (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
			return ERR_PTR(err);
	}

1893
	rcu_read_lock();
1894 1895
	list_for_each_entry_rcu(ptype,
			&ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
1896
		if (ptype->type == type && !ptype->dev && ptype->gso_segment) {
1897
			if (unlikely(skb->ip_summed != CHECKSUM_PARTIAL)) {
1898 1899 1900 1901
				err = ptype->gso_send_check(skb);
				segs = ERR_PTR(err);
				if (err || skb_gso_ok(skb, features))
					break;
1902 1903
				__skb_push(skb, (skb->data -
						 skb_network_header(skb)));
1904
			}
1905
			segs = ptype->gso_segment(skb, features);
1906 1907 1908 1909 1910
			break;
		}
	}
	rcu_read_unlock();

1911
	__skb_push(skb, skb->data - skb_mac_header(skb));
1912

1913 1914 1915 1916
	return segs;
}
EXPORT_SYMBOL(skb_gso_segment);

1917 1918 1919 1920 1921
/* Take action when hardware reception checksum errors are detected. */
#ifdef CONFIG_BUG
void netdev_rx_csum_fault(struct net_device *dev)
{
	if (net_ratelimit()) {
1922
		printk(KERN_ERR "%s: hw csum failure.\n",
1923
			dev ? dev->name : "<unknown>");
1924 1925 1926 1927 1928 1929
		dump_stack();
	}
}
EXPORT_SYMBOL(netdev_rx_csum_fault);
#endif

L
Linus Torvalds 已提交
1930 1931 1932 1933 1934
/* Actually, we should eliminate this check as soon as we know, that:
 * 1. IOMMU is present and allows to map all the memory.
 * 2. No high memory really exists on this machine.
 */

E
Eric Dumazet 已提交
1935
static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
L
Linus Torvalds 已提交
1936
{
1937
#ifdef CONFIG_HIGHMEM
L
Linus Torvalds 已提交
1938
	int i;
1939 1940 1941 1942 1943
	if (!(dev->features & NETIF_F_HIGHDMA)) {
		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
			if (PageHighMem(skb_shinfo(skb)->frags[i].page))
				return 1;
	}
L
Linus Torvalds 已提交
1944

1945 1946
	if (PCI_DMA_BUS_IS_PHYS) {
		struct device *pdev = dev->dev.parent;
L
Linus Torvalds 已提交
1947

E
Eric Dumazet 已提交
1948 1949
		if (!pdev)
			return 0;
1950 1951 1952 1953 1954 1955
		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
			dma_addr_t addr = page_to_phys(skb_shinfo(skb)->frags[i].page);
			if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
				return 1;
		}
	}
1956
#endif
L
Linus Torvalds 已提交
1957 1958 1959
	return 0;
}

1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985
struct dev_gso_cb {
	void (*destructor)(struct sk_buff *skb);
};

#define DEV_GSO_CB(skb) ((struct dev_gso_cb *)(skb)->cb)

static void dev_gso_skb_destructor(struct sk_buff *skb)
{
	struct dev_gso_cb *cb;

	do {
		struct sk_buff *nskb = skb->next;

		skb->next = nskb->next;
		nskb->next = NULL;
		kfree_skb(nskb);
	} while (skb->next);

	cb = DEV_GSO_CB(skb);
	if (cb->destructor)
		cb->destructor(skb);
}

/**
 *	dev_gso_segment - Perform emulated hardware segmentation on skb.
 *	@skb: buffer to segment
1986
 *	@features: device features as applicable to this skb
1987 1988 1989 1990
 *
 *	This function segments the given skb and stores the list of segments
 *	in skb->next.
 */
1991
static int dev_gso_segment(struct sk_buff *skb, int features)
1992 1993
{
	struct sk_buff *segs;
1994 1995 1996 1997 1998 1999

	segs = skb_gso_segment(skb, features);

	/* Verifying header integrity only. */
	if (!segs)
		return 0;
2000

2001
	if (IS_ERR(segs))
2002 2003 2004 2005 2006 2007 2008 2009 2010
		return PTR_ERR(segs);

	skb->next = segs;
	DEV_GSO_CB(skb)->destructor = skb->destructor;
	skb->destructor = dev_gso_skb_destructor;

	return 0;
}

E
Eric Dumazet 已提交
2011 2012
/*
 * Try to orphan skb early, right before transmission by the device.
2013 2014
 * We cannot orphan skb if tx timestamp is requested or the sk-reference
 * is needed on driver level for other reasons, e.g. see net/can/raw.c
E
Eric Dumazet 已提交
2015 2016 2017
 */
static inline void skb_orphan_try(struct sk_buff *skb)
{
2018 2019
	struct sock *sk = skb->sk;

2020
	if (sk && !skb_shinfo(skb)->tx_flags) {
2021 2022 2023 2024 2025
		/* skb_tx_hash() wont be able to get sk.
		 * We copy sk_hash into skb->rxhash
		 */
		if (!skb->rxhash)
			skb->rxhash = sk->sk_hash;
E
Eric Dumazet 已提交
2026
		skb_orphan(skb);
2027
	}
E
Eric Dumazet 已提交
2028 2029
}

2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040
static bool can_checksum_protocol(unsigned long features, __be16 protocol)
{
	return ((features & NETIF_F_GEN_CSUM) ||
		((features & NETIF_F_V4_CSUM) &&
		 protocol == htons(ETH_P_IP)) ||
		((features & NETIF_F_V6_CSUM) &&
		 protocol == htons(ETH_P_IPV6)) ||
		((features & NETIF_F_FCOE_CRC) &&
		 protocol == htons(ETH_P_FCOE)));
}

2041
static u32 harmonize_features(struct sk_buff *skb, __be16 protocol, u32 features)
2042
{
2043
	if (!can_checksum_protocol(features, protocol)) {
2044 2045 2046 2047 2048 2049 2050 2051 2052
		features &= ~NETIF_F_ALL_CSUM;
		features &= ~NETIF_F_SG;
	} else if (illegal_highdma(skb->dev, skb)) {
		features &= ~NETIF_F_SG;
	}

	return features;
}

2053
u32 netif_skb_features(struct sk_buff *skb)
2054 2055
{
	__be16 protocol = skb->protocol;
2056
	u32 features = skb->dev->features;
2057 2058 2059 2060

	if (protocol == htons(ETH_P_8021Q)) {
		struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
		protocol = veh->h_vlan_encapsulated_proto;
2061 2062 2063
	} else if (!vlan_tx_tag_present(skb)) {
		return harmonize_features(skb, protocol, features);
	}
2064

2065
	features &= (skb->dev->vlan_features | NETIF_F_HW_VLAN_TX);
2066 2067 2068 2069 2070

	if (protocol != htons(ETH_P_8021Q)) {
		return harmonize_features(skb, protocol, features);
	} else {
		features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST |
2071
				NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_TX;
2072 2073
		return harmonize_features(skb, protocol, features);
	}
2074
}
2075
EXPORT_SYMBOL(netif_skb_features);
2076

2077 2078 2079 2080 2081 2082 2083 2084
/*
 * Returns true if either:
 *	1. skb has frag_list and the device doesn't support FRAGLIST, or
 *	2. skb is fragmented and the device does not support SG, or if
 *	   at least one of fragments is in highmem and device does not
 *	   support DMA from it.
 */
static inline int skb_needs_linearize(struct sk_buff *skb,
2085
				      int features)
2086
{
2087 2088 2089
	return skb_is_nonlinear(skb) &&
			((skb_has_frag_list(skb) &&
				!(features & NETIF_F_FRAGLIST)) ||
2090
			(skb_shinfo(skb)->nr_frags &&
2091
				!(features & NETIF_F_SG)));
2092 2093
}

2094 2095
int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev,
			struct netdev_queue *txq)
2096
{
2097
	const struct net_device_ops *ops = dev->netdev_ops;
2098
	int rc = NETDEV_TX_OK;
2099
	unsigned int skb_len;
2100

2101
	if (likely(!skb->next)) {
2102
		u32 features;
2103

2104
		/*
L
Lucas De Marchi 已提交
2105
		 * If device doesn't need skb->dst, release it right now while
2106 2107
		 * its hot in this cpu cache
		 */
E
Eric Dumazet 已提交
2108 2109 2110
		if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
			skb_dst_drop(skb);

2111 2112 2113
		if (!list_empty(&ptype_all))
			dev_queue_xmit_nit(skb, dev);

E
Eric Dumazet 已提交
2114
		skb_orphan_try(skb);
2115

2116 2117
		features = netif_skb_features(skb);

2118
		if (vlan_tx_tag_present(skb) &&
2119
		    !(features & NETIF_F_HW_VLAN_TX)) {
2120 2121 2122 2123 2124 2125 2126
			skb = __vlan_put_tag(skb, vlan_tx_tag_get(skb));
			if (unlikely(!skb))
				goto out;

			skb->vlan_tci = 0;
		}

2127
		if (netif_needs_gso(skb, features)) {
2128
			if (unlikely(dev_gso_segment(skb, features)))
2129 2130 2131
				goto out_kfree_skb;
			if (skb->next)
				goto gso;
2132
		} else {
2133
			if (skb_needs_linearize(skb, features) &&
2134 2135 2136 2137 2138 2139 2140 2141
			    __skb_linearize(skb))
				goto out_kfree_skb;

			/* If packet is not checksummed and device does not
			 * support checksumming for this protocol, complete
			 * checksumming here.
			 */
			if (skb->ip_summed == CHECKSUM_PARTIAL) {
2142 2143
				skb_set_transport_header(skb,
					skb_checksum_start_offset(skb));
2144
				if (!(features & NETIF_F_ALL_CSUM) &&
2145 2146 2147
				     skb_checksum_help(skb))
					goto out_kfree_skb;
			}
2148 2149
		}

2150
		skb_len = skb->len;
2151
		rc = ops->ndo_start_xmit(skb, dev);
2152
		trace_net_dev_xmit(skb, rc, dev, skb_len);
2153
		if (rc == NETDEV_TX_OK)
E
Eric Dumazet 已提交
2154
			txq_trans_update(txq);
2155
		return rc;
2156 2157
	}

2158
gso:
2159 2160 2161 2162 2163
	do {
		struct sk_buff *nskb = skb->next;

		skb->next = nskb->next;
		nskb->next = NULL;
2164 2165

		/*
L
Lucas De Marchi 已提交
2166
		 * If device doesn't need nskb->dst, release it right now while
2167 2168 2169 2170 2171
		 * its hot in this cpu cache
		 */
		if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
			skb_dst_drop(nskb);

2172
		skb_len = nskb->len;
2173
		rc = ops->ndo_start_xmit(nskb, dev);
2174
		trace_net_dev_xmit(nskb, rc, dev, skb_len);
2175
		if (unlikely(rc != NETDEV_TX_OK)) {
2176 2177
			if (rc & ~NETDEV_TX_MASK)
				goto out_kfree_gso_skb;
2178
			nskb->next = skb->next;
2179 2180 2181
			skb->next = nskb;
			return rc;
		}
E
Eric Dumazet 已提交
2182
		txq_trans_update(txq);
2183
		if (unlikely(netif_tx_queue_stopped(txq) && skb->next))
2184
			return NETDEV_TX_BUSY;
2185
	} while (skb->next);
2186

2187 2188 2189
out_kfree_gso_skb:
	if (likely(skb->next == NULL))
		skb->destructor = DEV_GSO_CB(skb)->destructor;
2190 2191
out_kfree_skb:
	kfree_skb(skb);
2192
out:
2193
	return rc;
2194 2195
}

T
Tom Herbert 已提交
2196
static u32 hashrnd __read_mostly;
D
David S. Miller 已提交
2197

2198 2199 2200 2201 2202 2203
/*
 * Returns a Tx hash based on the given packet descriptor a Tx queues' number
 * to be used as a distribution range.
 */
u16 __skb_tx_hash(const struct net_device *dev, const struct sk_buff *skb,
		  unsigned int num_tx_queues)
2204
{
2205
	u32 hash;
2206 2207
	u16 qoffset = 0;
	u16 qcount = num_tx_queues;
D
David S. Miller 已提交
2208

2209 2210
	if (skb_rx_queue_recorded(skb)) {
		hash = skb_get_rx_queue(skb);
2211 2212
		while (unlikely(hash >= num_tx_queues))
			hash -= num_tx_queues;
2213 2214
		return hash;
	}
2215

2216 2217 2218 2219 2220 2221
	if (dev->num_tc) {
		u8 tc = netdev_get_prio_tc_map(dev, skb->priority);
		qoffset = dev->tc_to_txq[tc].offset;
		qcount = dev->tc_to_txq[tc].count;
	}

2222
	if (skb->sk && skb->sk->sk_hash)
2223
		hash = skb->sk->sk_hash;
2224
	else
2225
		hash = (__force u16) skb->protocol ^ skb->rxhash;
T
Tom Herbert 已提交
2226
	hash = jhash_1word(hash, hashrnd);
D
David S. Miller 已提交
2227

2228
	return (u16) (((u64) hash * qcount) >> 32) + qoffset;
2229
}
2230
EXPORT_SYMBOL(__skb_tx_hash);
2231

2232 2233 2234 2235
static inline u16 dev_cap_txqueue(struct net_device *dev, u16 queue_index)
{
	if (unlikely(queue_index >= dev->real_num_tx_queues)) {
		if (net_ratelimit()) {
E
Eric Dumazet 已提交
2236 2237 2238
			pr_warning("%s selects TX queue %d, but "
				"real number of TX queues is %d\n",
				dev->name, queue_index, dev->real_num_tx_queues);
2239 2240 2241 2242 2243 2244
		}
		return 0;
	}
	return queue_index;
}

T
Tom Herbert 已提交
2245 2246
static inline int get_xps_queue(struct net_device *dev, struct sk_buff *skb)
{
T
Tom Herbert 已提交
2247
#ifdef CONFIG_XPS
T
Tom Herbert 已提交
2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282
	struct xps_dev_maps *dev_maps;
	struct xps_map *map;
	int queue_index = -1;

	rcu_read_lock();
	dev_maps = rcu_dereference(dev->xps_maps);
	if (dev_maps) {
		map = rcu_dereference(
		    dev_maps->cpu_map[raw_smp_processor_id()]);
		if (map) {
			if (map->len == 1)
				queue_index = map->queues[0];
			else {
				u32 hash;
				if (skb->sk && skb->sk->sk_hash)
					hash = skb->sk->sk_hash;
				else
					hash = (__force u16) skb->protocol ^
					    skb->rxhash;
				hash = jhash_1word(hash, hashrnd);
				queue_index = map->queues[
				    ((u64)hash * map->len) >> 32];
			}
			if (unlikely(queue_index >= dev->real_num_tx_queues))
				queue_index = -1;
		}
	}
	rcu_read_unlock();

	return queue_index;
#else
	return -1;
#endif
}

2283 2284 2285
static struct netdev_queue *dev_pick_tx(struct net_device *dev,
					struct sk_buff *skb)
{
2286
	int queue_index;
2287
	const struct net_device_ops *ops = dev->netdev_ops;
2288

2289 2290 2291
	if (dev->real_num_tx_queues == 1)
		queue_index = 0;
	else if (ops->ndo_select_queue) {
2292 2293 2294 2295 2296
		queue_index = ops->ndo_select_queue(dev, skb);
		queue_index = dev_cap_txqueue(dev, queue_index);
	} else {
		struct sock *sk = skb->sk;
		queue_index = sk_tx_queue_get(sk);
2297

2298 2299 2300
		if (queue_index < 0 || skb->ooo_okay ||
		    queue_index >= dev->real_num_tx_queues) {
			int old_index = queue_index;
2301

T
Tom Herbert 已提交
2302 2303 2304
			queue_index = get_xps_queue(dev, skb);
			if (queue_index < 0)
				queue_index = skb_tx_hash(dev, skb);
2305 2306 2307 2308

			if (queue_index != old_index && sk) {
				struct dst_entry *dst =
				    rcu_dereference_check(sk->sk_dst_cache, 1);
E
Eric Dumazet 已提交
2309 2310 2311 2312

				if (dst && skb_dst(skb) == dst)
					sk_tx_queue_set(sk, queue_index);
			}
2313 2314
		}
	}
2315

2316 2317
	skb_set_queue_mapping(skb, queue_index);
	return netdev_get_tx_queue(dev, queue_index);
2318 2319
}

2320 2321 2322 2323 2324
static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
				 struct net_device *dev,
				 struct netdev_queue *txq)
{
	spinlock_t *root_lock = qdisc_lock(q);
E
Eric Dumazet 已提交
2325
	bool contended;
2326 2327
	int rc;

E
Eric Dumazet 已提交
2328 2329
	qdisc_skb_cb(skb)->pkt_len = skb->len;
	qdisc_calculate_pkt_len(skb, q);
2330 2331 2332 2333 2334 2335
	/*
	 * Heuristic to force contended enqueues to serialize on a
	 * separate lock before trying to get qdisc main lock.
	 * This permits __QDISC_STATE_RUNNING owner to get the lock more often
	 * and dequeue packets faster.
	 */
E
Eric Dumazet 已提交
2336
	contended = qdisc_is_running(q);
2337 2338 2339
	if (unlikely(contended))
		spin_lock(&q->busylock);

2340 2341 2342 2343 2344
	spin_lock(root_lock);
	if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
		kfree_skb(skb);
		rc = NET_XMIT_DROP;
	} else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
2345
		   qdisc_run_begin(q)) {
2346 2347 2348 2349 2350
		/*
		 * This is a work-conserving queue; there are no old skbs
		 * waiting to be sent out; and the qdisc is not running -
		 * xmit the skb directly.
		 */
E
Eric Dumazet 已提交
2351 2352
		if (!(dev->priv_flags & IFF_XMIT_DST_RELEASE))
			skb_dst_force(skb);
2353 2354 2355

		qdisc_bstats_update(q, skb);

2356 2357 2358 2359 2360
		if (sch_direct_xmit(skb, q, dev, txq, root_lock)) {
			if (unlikely(contended)) {
				spin_unlock(&q->busylock);
				contended = false;
			}
2361
			__qdisc_run(q);
2362
		} else
2363
			qdisc_run_end(q);
2364 2365 2366

		rc = NET_XMIT_SUCCESS;
	} else {
E
Eric Dumazet 已提交
2367
		skb_dst_force(skb);
E
Eric Dumazet 已提交
2368
		rc = q->enqueue(skb, q) & NET_XMIT_MASK;
2369 2370 2371 2372 2373 2374 2375
		if (qdisc_run_begin(q)) {
			if (unlikely(contended)) {
				spin_unlock(&q->busylock);
				contended = false;
			}
			__qdisc_run(q);
		}
2376 2377
	}
	spin_unlock(root_lock);
2378 2379
	if (unlikely(contended))
		spin_unlock(&q->busylock);
2380 2381 2382
	return rc;
}

2383
static DEFINE_PER_CPU(int, xmit_recursion);
2384
#define RECURSION_LIMIT 10
2385

2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410
/**
 *	dev_queue_xmit - transmit a buffer
 *	@skb: buffer to transmit
 *
 *	Queue a buffer for transmission to a network device. The caller must
 *	have set the device and priority and built the buffer before calling
 *	this function. The function can be called from an interrupt.
 *
 *	A negative errno code is returned on a failure. A success does not
 *	guarantee the frame will be transmitted as it may be dropped due
 *	to congestion or traffic shaping.
 *
 * -----------------------------------------------------------------------------------
 *      I notice this method can also return errors from the queue disciplines,
 *      including NET_XMIT_DROP, which is a positive value.  So, errors can also
 *      be positive.
 *
 *      Regardless of the return value, the skb is consumed, so it is currently
 *      difficult to retry a send to this method.  (You can bump the ref count
 *      before sending to hold a reference for retry if you are careful.)
 *
 *      When calling this method, interrupts MUST be enabled.  This is because
 *      the BH enable code must have IRQs enabled so that it will not deadlock.
 *          --BLG
 */
L
Linus Torvalds 已提交
2411 2412 2413
int dev_queue_xmit(struct sk_buff *skb)
{
	struct net_device *dev = skb->dev;
2414
	struct netdev_queue *txq;
L
Linus Torvalds 已提交
2415 2416 2417
	struct Qdisc *q;
	int rc = -ENOMEM;

2418 2419
	/* Disable soft irqs for various locks below. Also
	 * stops preemption for RCU.
L
Linus Torvalds 已提交
2420
	 */
2421
	rcu_read_lock_bh();
L
Linus Torvalds 已提交
2422

2423
	txq = dev_pick_tx(dev, skb);
2424
	q = rcu_dereference_bh(txq->qdisc);
2425

L
Linus Torvalds 已提交
2426
#ifdef CONFIG_NET_CLS_ACT
E
Eric Dumazet 已提交
2427
	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
L
Linus Torvalds 已提交
2428
#endif
2429
	trace_net_dev_queue(skb);
L
Linus Torvalds 已提交
2430
	if (q->enqueue) {
2431
		rc = __dev_xmit_skb(skb, q, dev, txq);
2432
		goto out;
L
Linus Torvalds 已提交
2433 2434 2435 2436 2437
	}

	/* The device has no queue. Common case for software devices:
	   loopback, all the sorts of tunnels...

H
Herbert Xu 已提交
2438 2439
	   Really, it is unlikely that netif_tx_lock protection is necessary
	   here.  (f.e. loopback and IP tunnels are clean ignoring statistics
L
Linus Torvalds 已提交
2440 2441 2442 2443 2444 2445 2446 2447 2448 2449
	   counters.)
	   However, it is possible, that they rely on protection
	   made by us here.

	   Check this and shot the lock. It is not prone from deadlocks.
	   Either shot noqueue qdisc, it is even simpler 8)
	 */
	if (dev->flags & IFF_UP) {
		int cpu = smp_processor_id(); /* ok because BHs are off */

2450
		if (txq->xmit_lock_owner != cpu) {
L
Linus Torvalds 已提交
2451

2452 2453 2454
			if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
				goto recursion_alert;

2455
			HARD_TX_LOCK(dev, txq, cpu);
L
Linus Torvalds 已提交
2456

2457
			if (!netif_tx_queue_stopped(txq)) {
2458
				__this_cpu_inc(xmit_recursion);
2459
				rc = dev_hard_start_xmit(skb, dev, txq);
2460
				__this_cpu_dec(xmit_recursion);
2461
				if (dev_xmit_complete(rc)) {
2462
					HARD_TX_UNLOCK(dev, txq);
L
Linus Torvalds 已提交
2463 2464 2465
					goto out;
				}
			}
2466
			HARD_TX_UNLOCK(dev, txq);
L
Linus Torvalds 已提交
2467 2468 2469 2470 2471
			if (net_ratelimit())
				printk(KERN_CRIT "Virtual device %s asks to "
				       "queue packet!\n", dev->name);
		} else {
			/* Recursion is detected! It is possible,
2472 2473 2474
			 * unfortunately
			 */
recursion_alert:
L
Linus Torvalds 已提交
2475 2476 2477 2478 2479 2480 2481
			if (net_ratelimit())
				printk(KERN_CRIT "Dead loop on virtual device "
				       "%s, fix it urgently!\n", dev->name);
		}
	}

	rc = -ENETDOWN;
2482
	rcu_read_unlock_bh();
L
Linus Torvalds 已提交
2483 2484 2485 2486

	kfree_skb(skb);
	return rc;
out:
2487
	rcu_read_unlock_bh();
L
Linus Torvalds 已提交
2488 2489
	return rc;
}
E
Eric Dumazet 已提交
2490
EXPORT_SYMBOL(dev_queue_xmit);
L
Linus Torvalds 已提交
2491 2492 2493 2494 2495 2496


/*=======================================================================
			Receiver routines
  =======================================================================*/

2497
int netdev_max_backlog __read_mostly = 1000;
E
Eric Dumazet 已提交
2498
int netdev_tstamp_prequeue __read_mostly = 1;
2499 2500
int netdev_budget __read_mostly = 300;
int weight_p __read_mostly = 64;            /* old backlog weight */
L
Linus Torvalds 已提交
2501

E
Eric Dumazet 已提交
2502 2503 2504 2505 2506 2507 2508 2509
/* Called with irq disabled */
static inline void ____napi_schedule(struct softnet_data *sd,
				     struct napi_struct *napi)
{
	list_add_tail(&napi->poll_list, &sd->poll_list);
	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
}

T
Tom Herbert 已提交
2510
/*
2511 2512 2513
 * __skb_get_rxhash: calculate a flow hash based on src/dst addresses
 * and src/dst port numbers. Returns a non-zero hash number on success
 * and 0 on failure.
T
Tom Herbert 已提交
2514
 */
2515
__u32 __skb_get_rxhash(struct sk_buff *skb)
T
Tom Herbert 已提交
2516
{
2517
	int nhoff, hash = 0, poff;
2518 2519
	const struct ipv6hdr *ip6;
	const struct iphdr *ip;
T
Tom Herbert 已提交
2520
	u8 ip_proto;
C
Changli Gao 已提交
2521 2522 2523 2524 2525
	u32 addr1, addr2, ihl;
	union {
		u32 v32;
		u16 v16[2];
	} ports;
T
Tom Herbert 已提交
2526

2527
	nhoff = skb_network_offset(skb);
T
Tom Herbert 已提交
2528 2529 2530

	switch (skb->protocol) {
	case __constant_htons(ETH_P_IP):
2531
		if (!pskb_may_pull(skb, sizeof(*ip) + nhoff))
T
Tom Herbert 已提交
2532 2533
			goto done;

2534
		ip = (const struct iphdr *) (skb->data + nhoff);
2535 2536 2537 2538
		if (ip->frag_off & htons(IP_MF | IP_OFFSET))
			ip_proto = 0;
		else
			ip_proto = ip->protocol;
E
Eric Dumazet 已提交
2539 2540
		addr1 = (__force u32) ip->saddr;
		addr2 = (__force u32) ip->daddr;
T
Tom Herbert 已提交
2541 2542 2543
		ihl = ip->ihl;
		break;
	case __constant_htons(ETH_P_IPV6):
2544
		if (!pskb_may_pull(skb, sizeof(*ip6) + nhoff))
T
Tom Herbert 已提交
2545 2546
			goto done;

2547
		ip6 = (const struct ipv6hdr *) (skb->data + nhoff);
T
Tom Herbert 已提交
2548
		ip_proto = ip6->nexthdr;
E
Eric Dumazet 已提交
2549 2550
		addr1 = (__force u32) ip6->saddr.s6_addr32[3];
		addr2 = (__force u32) ip6->daddr.s6_addr32[3];
T
Tom Herbert 已提交
2551 2552 2553 2554 2555
		ihl = (40 >> 2);
		break;
	default:
		goto done;
	}
2556

2557 2558 2559 2560 2561 2562
	ports.v32 = 0;
	poff = proto_ports_offset(ip_proto);
	if (poff >= 0) {
		nhoff += ihl * 4 + poff;
		if (pskb_may_pull(skb, nhoff + 4)) {
			ports.v32 = * (__force u32 *) (skb->data + nhoff);
C
Changli Gao 已提交
2563 2564
			if (ports.v16[1] < ports.v16[0])
				swap(ports.v16[0], ports.v16[1]);
E
Eric Dumazet 已提交
2565
		}
T
Tom Herbert 已提交
2566 2567
	}

E
Eric Dumazet 已提交
2568 2569 2570
	/* get a consistent hash (same value on both flow directions) */
	if (addr2 < addr1)
		swap(addr1, addr2);
T
Tom Herbert 已提交
2571

2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583
	hash = jhash_3words(addr1, addr2, ports.v32, hashrnd);
	if (!hash)
		hash = 1;

done:
	return hash;
}
EXPORT_SYMBOL(__skb_get_rxhash);

#ifdef CONFIG_RPS

/* One global table that all flow-based protocols share. */
E
Eric Dumazet 已提交
2584
struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
2585 2586
EXPORT_SYMBOL(rps_sock_flow_table);

2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603
static struct rps_dev_flow *
set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
	    struct rps_dev_flow *rflow, u16 next_cpu)
{
	u16 tcpu;

	tcpu = rflow->cpu = next_cpu;
	if (tcpu != RPS_NO_CPU) {
#ifdef CONFIG_RFS_ACCEL
		struct netdev_rx_queue *rxqueue;
		struct rps_dev_flow_table *flow_table;
		struct rps_dev_flow *old_rflow;
		u32 flow_id;
		u16 rxq_index;
		int rc;

		/* Should we steer this flow to a different hardware queue? */
2604 2605
		if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
		    !(dev->features & NETIF_F_NTUPLE))
2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634
			goto out;
		rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
		if (rxq_index == skb_get_rx_queue(skb))
			goto out;

		rxqueue = dev->_rx + rxq_index;
		flow_table = rcu_dereference(rxqueue->rps_flow_table);
		if (!flow_table)
			goto out;
		flow_id = skb->rxhash & flow_table->mask;
		rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
							rxq_index, flow_id);
		if (rc < 0)
			goto out;
		old_rflow = rflow;
		rflow = &flow_table->flows[flow_id];
		rflow->cpu = next_cpu;
		rflow->filter = rc;
		if (old_rflow->filter == rflow->filter)
			old_rflow->filter = RPS_NO_FILTER;
	out:
#endif
		rflow->last_qtail =
			per_cpu(softnet_data, tcpu).input_queue_head;
	}

	return rflow;
}

2635 2636 2637 2638 2639 2640 2641 2642 2643
/*
 * get_rps_cpu is called from netif_receive_skb and returns the target
 * CPU from the RPS map of the receiving queue for a given skb.
 * rcu_read_lock must be held on entry.
 */
static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
		       struct rps_dev_flow **rflowp)
{
	struct netdev_rx_queue *rxqueue;
E
Eric Dumazet 已提交
2644
	struct rps_map *map;
2645 2646 2647 2648 2649 2650 2651
	struct rps_dev_flow_table *flow_table;
	struct rps_sock_flow_table *sock_flow_table;
	int cpu = -1;
	u16 tcpu;

	if (skb_rx_queue_recorded(skb)) {
		u16 index = skb_get_rx_queue(skb);
2652 2653 2654 2655 2656
		if (unlikely(index >= dev->real_num_rx_queues)) {
			WARN_ONCE(dev->real_num_rx_queues > 1,
				  "%s received packet on queue %u, but number "
				  "of RX queues is %u\n",
				  dev->name, index, dev->real_num_rx_queues);
2657 2658 2659 2660 2661 2662
			goto done;
		}
		rxqueue = dev->_rx + index;
	} else
		rxqueue = dev->_rx;

E
Eric Dumazet 已提交
2663 2664
	map = rcu_dereference(rxqueue->rps_map);
	if (map) {
2665 2666
		if (map->len == 1 &&
		    !rcu_dereference_raw(rxqueue->rps_flow_table)) {
2667 2668 2669 2670 2671
			tcpu = map->cpus[0];
			if (cpu_online(tcpu))
				cpu = tcpu;
			goto done;
		}
E
Eric Dumazet 已提交
2672
	} else if (!rcu_dereference_raw(rxqueue->rps_flow_table)) {
2673
		goto done;
2674
	}
2675

2676
	skb_reset_network_header(skb);
2677 2678 2679
	if (!skb_get_rxhash(skb))
		goto done;

T
Tom Herbert 已提交
2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705
	flow_table = rcu_dereference(rxqueue->rps_flow_table);
	sock_flow_table = rcu_dereference(rps_sock_flow_table);
	if (flow_table && sock_flow_table) {
		u16 next_cpu;
		struct rps_dev_flow *rflow;

		rflow = &flow_table->flows[skb->rxhash & flow_table->mask];
		tcpu = rflow->cpu;

		next_cpu = sock_flow_table->ents[skb->rxhash &
		    sock_flow_table->mask];

		/*
		 * If the desired CPU (where last recvmsg was done) is
		 * different from current CPU (one in the rx-queue flow
		 * table entry), switch if one of the following holds:
		 *   - Current CPU is unset (equal to RPS_NO_CPU).
		 *   - Current CPU is offline.
		 *   - The current CPU's queue tail has advanced beyond the
		 *     last packet that was enqueued using this table entry.
		 *     This guarantees that all previous packets for the flow
		 *     have been dequeued, thus preserving in order delivery.
		 */
		if (unlikely(tcpu != next_cpu) &&
		    (tcpu == RPS_NO_CPU || !cpu_online(tcpu) ||
		     ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
2706 2707 2708
		      rflow->last_qtail)) >= 0))
			rflow = set_rps_cpu(dev, skb, rflow, next_cpu);

T
Tom Herbert 已提交
2709 2710 2711 2712 2713 2714 2715
		if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
			*rflowp = rflow;
			cpu = tcpu;
			goto done;
		}
	}

T
Tom Herbert 已提交
2716
	if (map) {
T
Tom Herbert 已提交
2717
		tcpu = map->cpus[((u64) skb->rxhash * map->len) >> 32];
T
Tom Herbert 已提交
2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728

		if (cpu_online(tcpu)) {
			cpu = tcpu;
			goto done;
		}
	}

done:
	return cpu;
}

2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765 2766 2767 2768
#ifdef CONFIG_RFS_ACCEL

/**
 * rps_may_expire_flow - check whether an RFS hardware filter may be removed
 * @dev: Device on which the filter was set
 * @rxq_index: RX queue index
 * @flow_id: Flow ID passed to ndo_rx_flow_steer()
 * @filter_id: Filter ID returned by ndo_rx_flow_steer()
 *
 * Drivers that implement ndo_rx_flow_steer() should periodically call
 * this function for each installed filter and remove the filters for
 * which it returns %true.
 */
bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
			 u32 flow_id, u16 filter_id)
{
	struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
	struct rps_dev_flow_table *flow_table;
	struct rps_dev_flow *rflow;
	bool expire = true;
	int cpu;

	rcu_read_lock();
	flow_table = rcu_dereference(rxqueue->rps_flow_table);
	if (flow_table && flow_id <= flow_table->mask) {
		rflow = &flow_table->flows[flow_id];
		cpu = ACCESS_ONCE(rflow->cpu);
		if (rflow->filter == filter_id && cpu != RPS_NO_CPU &&
		    ((int)(per_cpu(softnet_data, cpu).input_queue_head -
			   rflow->last_qtail) <
		     (int)(10 * flow_table->mask)))
			expire = false;
	}
	rcu_read_unlock();
	return expire;
}
EXPORT_SYMBOL(rps_may_expire_flow);

#endif /* CONFIG_RFS_ACCEL */

T
Tom Herbert 已提交
2769
/* Called from hardirq (IPI) context */
E
Eric Dumazet 已提交
2770
static void rps_trigger_softirq(void *data)
T
Tom Herbert 已提交
2771
{
E
Eric Dumazet 已提交
2772 2773
	struct softnet_data *sd = data;

E
Eric Dumazet 已提交
2774
	____napi_schedule(sd, &sd->backlog);
C
Changli Gao 已提交
2775
	sd->received_rps++;
T
Tom Herbert 已提交
2776
}
E
Eric Dumazet 已提交
2777

T
Tom Herbert 已提交
2778
#endif /* CONFIG_RPS */
T
Tom Herbert 已提交
2779

E
Eric Dumazet 已提交
2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800
/*
 * Check if this softnet_data structure is another cpu one
 * If yes, queue it to our IPI list and return 1
 * If no, return 0
 */
static int rps_ipi_queued(struct softnet_data *sd)
{
#ifdef CONFIG_RPS
	struct softnet_data *mysd = &__get_cpu_var(softnet_data);

	if (sd != mysd) {
		sd->rps_ipi_next = mysd->rps_ipi_list;
		mysd->rps_ipi_list = sd;

		__raise_softirq_irqoff(NET_RX_SOFTIRQ);
		return 1;
	}
#endif /* CONFIG_RPS */
	return 0;
}

T
Tom Herbert 已提交
2801 2802 2803 2804
/*
 * enqueue_to_backlog is called to queue an skb to a per CPU backlog
 * queue (may be a remote CPU queue).
 */
T
Tom Herbert 已提交
2805 2806
static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
			      unsigned int *qtail)
T
Tom Herbert 已提交
2807
{
E
Eric Dumazet 已提交
2808
	struct softnet_data *sd;
T
Tom Herbert 已提交
2809 2810
	unsigned long flags;

E
Eric Dumazet 已提交
2811
	sd = &per_cpu(softnet_data, cpu);
T
Tom Herbert 已提交
2812 2813 2814

	local_irq_save(flags);

E
Eric Dumazet 已提交
2815
	rps_lock(sd);
2816 2817
	if (skb_queue_len(&sd->input_pkt_queue) <= netdev_max_backlog) {
		if (skb_queue_len(&sd->input_pkt_queue)) {
T
Tom Herbert 已提交
2818
enqueue:
E
Eric Dumazet 已提交
2819
			__skb_queue_tail(&sd->input_pkt_queue, skb);
2820
			input_queue_tail_incr_save(sd, qtail);
E
Eric Dumazet 已提交
2821
			rps_unlock(sd);
2822
			local_irq_restore(flags);
T
Tom Herbert 已提交
2823 2824 2825
			return NET_RX_SUCCESS;
		}

2826 2827 2828 2829
		/* Schedule NAPI for backlog device
		 * We can use non atomic operation since we own the queue lock
		 */
		if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
E
Eric Dumazet 已提交
2830
			if (!rps_ipi_queued(sd))
E
Eric Dumazet 已提交
2831
				____napi_schedule(sd, &sd->backlog);
T
Tom Herbert 已提交
2832 2833 2834 2835
		}
		goto enqueue;
	}

C
Changli Gao 已提交
2836
	sd->dropped++;
E
Eric Dumazet 已提交
2837
	rps_unlock(sd);
T
Tom Herbert 已提交
2838 2839 2840

	local_irq_restore(flags);

2841
	atomic_long_inc(&skb->dev->rx_dropped);
T
Tom Herbert 已提交
2842 2843 2844
	kfree_skb(skb);
	return NET_RX_DROP;
}
L
Linus Torvalds 已提交
2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862

/**
 *	netif_rx	-	post buffer to the network code
 *	@skb: buffer to post
 *
 *	This function receives a packet from a device driver and queues it for
 *	the upper (protocol) levels to process.  It always succeeds. The buffer
 *	may be dropped during processing for congestion control or by the
 *	protocol layers.
 *
 *	return values:
 *	NET_RX_SUCCESS	(no congestion)
 *	NET_RX_DROP     (packet was dropped)
 *
 */

int netif_rx(struct sk_buff *skb)
{
2863
	int ret;
L
Linus Torvalds 已提交
2864 2865 2866 2867 2868

	/* if netpoll wants it, pretend we never saw it */
	if (netpoll_rx(skb))
		return NET_RX_DROP;

E
Eric Dumazet 已提交
2869 2870
	if (netdev_tstamp_prequeue)
		net_timestamp_check(skb);
L
Linus Torvalds 已提交
2871

2872
	trace_netif_rx(skb);
E
Eric Dumazet 已提交
2873
#ifdef CONFIG_RPS
2874
	{
T
Tom Herbert 已提交
2875
		struct rps_dev_flow voidflow, *rflow = &voidflow;
2876 2877
		int cpu;

2878
		preempt_disable();
2879
		rcu_read_lock();
T
Tom Herbert 已提交
2880 2881

		cpu = get_rps_cpu(skb->dev, skb, &rflow);
2882 2883
		if (cpu < 0)
			cpu = smp_processor_id();
T
Tom Herbert 已提交
2884 2885 2886

		ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);

2887
		rcu_read_unlock();
2888
		preempt_enable();
2889
	}
2890
#else
T
Tom Herbert 已提交
2891 2892 2893 2894 2895
	{
		unsigned int qtail;
		ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
		put_cpu();
	}
2896
#endif
2897
	return ret;
L
Linus Torvalds 已提交
2898
}
E
Eric Dumazet 已提交
2899
EXPORT_SYMBOL(netif_rx);
L
Linus Torvalds 已提交
2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930

int netif_rx_ni(struct sk_buff *skb)
{
	int err;

	preempt_disable();
	err = netif_rx(skb);
	if (local_softirq_pending())
		do_softirq();
	preempt_enable();

	return err;
}
EXPORT_SYMBOL(netif_rx_ni);

static void net_tx_action(struct softirq_action *h)
{
	struct softnet_data *sd = &__get_cpu_var(softnet_data);

	if (sd->completion_queue) {
		struct sk_buff *clist;

		local_irq_disable();
		clist = sd->completion_queue;
		sd->completion_queue = NULL;
		local_irq_enable();

		while (clist) {
			struct sk_buff *skb = clist;
			clist = clist->next;

2931
			WARN_ON(atomic_read(&skb->users));
2932
			trace_kfree_skb(skb, net_tx_action);
L
Linus Torvalds 已提交
2933 2934 2935 2936 2937
			__kfree_skb(skb);
		}
	}

	if (sd->output_queue) {
2938
		struct Qdisc *head;
L
Linus Torvalds 已提交
2939 2940 2941 2942

		local_irq_disable();
		head = sd->output_queue;
		sd->output_queue = NULL;
2943
		sd->output_queue_tailp = &sd->output_queue;
L
Linus Torvalds 已提交
2944 2945 2946
		local_irq_enable();

		while (head) {
2947 2948 2949
			struct Qdisc *q = head;
			spinlock_t *root_lock;

L
Linus Torvalds 已提交
2950 2951
			head = head->next_sched;

2952
			root_lock = qdisc_lock(q);
2953
			if (spin_trylock(root_lock)) {
2954 2955 2956
				smp_mb__before_clear_bit();
				clear_bit(__QDISC_STATE_SCHED,
					  &q->state);
2957 2958
				qdisc_run(q);
				spin_unlock(root_lock);
L
Linus Torvalds 已提交
2959
			} else {
2960
				if (!test_bit(__QDISC_STATE_DEACTIVATED,
2961
					      &q->state)) {
2962
					__netif_reschedule(q);
2963 2964 2965 2966 2967
				} else {
					smp_mb__before_clear_bit();
					clear_bit(__QDISC_STATE_SCHED,
						  &q->state);
				}
L
Linus Torvalds 已提交
2968 2969 2970 2971 2972
			}
		}
	}
}

2973 2974
#if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
    (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
2975 2976 2977
/* This hook is defined here for ATM LANE */
int (*br_fdb_test_addr_hook)(struct net_device *dev,
			     unsigned char *addr) __read_mostly;
2978
EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
2979
#endif
L
Linus Torvalds 已提交
2980 2981 2982 2983 2984 2985

#ifdef CONFIG_NET_CLS_ACT
/* TODO: Maybe we should just force sch_ingress to be compiled in
 * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
 * a compare and 2 stores extra right now if we dont have it on
 * but have CONFIG_NET_CLS_ACT
L
Lucas De Marchi 已提交
2986 2987
 * NOTE: This doesn't stop any functionality; if you dont have
 * the ingress scheduler, you just can't add policies on ingress.
L
Linus Torvalds 已提交
2988 2989
 *
 */
2990
static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
L
Linus Torvalds 已提交
2991 2992
{
	struct net_device *dev = skb->dev;
2993
	u32 ttl = G_TC_RTTL(skb->tc_verd);
2994 2995
	int result = TC_ACT_OK;
	struct Qdisc *q;
2996

2997 2998 2999 3000
	if (unlikely(MAX_RED_LOOP < ttl++)) {
		if (net_ratelimit())
			pr_warning( "Redir loop detected Dropping packet (%d->%d)\n",
			       skb->skb_iif, dev->ifindex);
3001 3002
		return TC_ACT_SHOT;
	}
L
Linus Torvalds 已提交
3003

3004 3005
	skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl);
	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
L
Linus Torvalds 已提交
3006

3007
	q = rxq->qdisc;
3008
	if (q != &noop_qdisc) {
3009
		spin_lock(qdisc_lock(q));
3010 3011
		if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
			result = qdisc_enqueue_root(skb, q);
3012 3013
		spin_unlock(qdisc_lock(q));
	}
3014 3015 3016

	return result;
}
3017

3018 3019 3020 3021
static inline struct sk_buff *handle_ing(struct sk_buff *skb,
					 struct packet_type **pt_prev,
					 int *ret, struct net_device *orig_dev)
{
3022 3023 3024
	struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);

	if (!rxq || rxq->qdisc == &noop_qdisc)
3025
		goto out;
L
Linus Torvalds 已提交
3026

3027 3028 3029
	if (*pt_prev) {
		*ret = deliver_skb(skb, *pt_prev, orig_dev);
		*pt_prev = NULL;
L
Linus Torvalds 已提交
3030 3031
	}

3032
	switch (ing_filter(skb, rxq)) {
3033 3034 3035 3036 3037 3038 3039 3040 3041
	case TC_ACT_SHOT:
	case TC_ACT_STOLEN:
		kfree_skb(skb);
		return NULL;
	}

out:
	skb->tc_verd = 0;
	return skb;
L
Linus Torvalds 已提交
3042 3043 3044
}
#endif

3045 3046 3047 3048
/**
 *	netdev_rx_handler_register - register receive handler
 *	@dev: device to register a handler for
 *	@rx_handler: receive handler to register
J
Jiri Pirko 已提交
3049
 *	@rx_handler_data: data pointer that is used by rx handler
3050 3051 3052 3053 3054 3055
 *
 *	Register a receive hander for a device. This handler will then be
 *	called from __netif_receive_skb. A negative errno code is returned
 *	on a failure.
 *
 *	The caller must hold the rtnl_mutex.
3056 3057
 *
 *	For a general description of rx_handler, see enum rx_handler_result.
3058 3059
 */
int netdev_rx_handler_register(struct net_device *dev,
J
Jiri Pirko 已提交
3060 3061
			       rx_handler_func_t *rx_handler,
			       void *rx_handler_data)
3062 3063 3064 3065 3066 3067
{
	ASSERT_RTNL();

	if (dev->rx_handler)
		return -EBUSY;

J
Jiri Pirko 已提交
3068
	rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3069 3070 3071 3072 3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085 3086 3087
	rcu_assign_pointer(dev->rx_handler, rx_handler);

	return 0;
}
EXPORT_SYMBOL_GPL(netdev_rx_handler_register);

/**
 *	netdev_rx_handler_unregister - unregister receive handler
 *	@dev: device to unregister a handler from
 *
 *	Unregister a receive hander from a device.
 *
 *	The caller must hold the rtnl_mutex.
 */
void netdev_rx_handler_unregister(struct net_device *dev)
{

	ASSERT_RTNL();
	rcu_assign_pointer(dev->rx_handler, NULL);
J
Jiri Pirko 已提交
3088
	rcu_assign_pointer(dev->rx_handler_data, NULL);
3089 3090 3091
}
EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);

3092
static int __netif_receive_skb(struct sk_buff *skb)
L
Linus Torvalds 已提交
3093 3094
{
	struct packet_type *ptype, *pt_prev;
3095
	rx_handler_func_t *rx_handler;
D
David S. Miller 已提交
3096
	struct net_device *orig_dev;
3097
	struct net_device *null_or_dev;
3098
	bool deliver_exact = false;
L
Linus Torvalds 已提交
3099
	int ret = NET_RX_DROP;
A
Al Viro 已提交
3100
	__be16 type;
L
Linus Torvalds 已提交
3101

E
Eric Dumazet 已提交
3102 3103
	if (!netdev_tstamp_prequeue)
		net_timestamp_check(skb);
3104

3105
	trace_netif_receive_skb(skb);
3106

L
Linus Torvalds 已提交
3107
	/* if we've gotten here through NAPI, check netpoll */
3108
	if (netpoll_receive_skb(skb))
L
Linus Torvalds 已提交
3109 3110
		return NET_RX_DROP;

3111 3112
	if (!skb->skb_iif)
		skb->skb_iif = skb->dev->ifindex;
J
Joe Eykholt 已提交
3113
	orig_dev = skb->dev;
3114

3115
	skb_reset_network_header(skb);
3116
	skb_reset_transport_header(skb);
3117
	skb->mac_len = skb->network_header - skb->mac_header;
L
Linus Torvalds 已提交
3118 3119 3120 3121 3122

	pt_prev = NULL;

	rcu_read_lock();

3123 3124 3125 3126
another_round:

	__this_cpu_inc(softnet_data.processed);

3127 3128 3129 3130 3131 3132
	if (skb->protocol == cpu_to_be16(ETH_P_8021Q)) {
		skb = vlan_untag(skb);
		if (unlikely(!skb))
			goto out;
	}

L
Linus Torvalds 已提交
3133 3134 3135 3136 3137 3138 3139 3140
#ifdef CONFIG_NET_CLS_ACT
	if (skb->tc_verd & TC_NCLS) {
		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
		goto ncls;
	}
#endif

	list_for_each_entry_rcu(ptype, &ptype_all, list) {
3141
		if (!ptype->dev || ptype->dev == skb->dev) {
3142
			if (pt_prev)
D
David S. Miller 已提交
3143
				ret = deliver_skb(skb, pt_prev, orig_dev);
L
Linus Torvalds 已提交
3144 3145 3146 3147 3148
			pt_prev = ptype;
		}
	}

#ifdef CONFIG_NET_CLS_ACT
3149 3150
	skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
	if (!skb)
L
Linus Torvalds 已提交
3151 3152 3153 3154
		goto out;
ncls:
#endif

3155 3156 3157 3158 3159 3160
	rx_handler = rcu_dereference(skb->dev->rx_handler);
	if (rx_handler) {
		if (pt_prev) {
			ret = deliver_skb(skb, pt_prev, orig_dev);
			pt_prev = NULL;
		}
3161 3162
		switch (rx_handler(&skb)) {
		case RX_HANDLER_CONSUMED:
3163
			goto out;
3164
		case RX_HANDLER_ANOTHER:
3165
			goto another_round;
3166 3167 3168 3169 3170 3171 3172
		case RX_HANDLER_EXACT:
			deliver_exact = true;
		case RX_HANDLER_PASS:
			break;
		default:
			BUG();
		}
3173
	}
L
Linus Torvalds 已提交
3174

3175 3176 3177 3178 3179
	if (vlan_tx_tag_present(skb)) {
		if (pt_prev) {
			ret = deliver_skb(skb, pt_prev, orig_dev);
			pt_prev = NULL;
		}
3180
		if (vlan_do_receive(&skb)) {
3181 3182 3183 3184 3185 3186
			ret = __netif_receive_skb(skb);
			goto out;
		} else if (unlikely(!skb))
			goto out;
	}

3187
	/* deliver only exact match when indicated */
3188
	null_or_dev = deliver_exact ? skb->dev : NULL;
3189

L
Linus Torvalds 已提交
3190
	type = skb->protocol;
3191 3192
	list_for_each_entry_rcu(ptype,
			&ptype_base[ntohs(type) & PTYPE_HASH_MASK], list) {
3193
		if (ptype->type == type &&
3194 3195
		    (ptype->dev == null_or_dev || ptype->dev == skb->dev ||
		     ptype->dev == orig_dev)) {
3196
			if (pt_prev)
D
David S. Miller 已提交
3197
				ret = deliver_skb(skb, pt_prev, orig_dev);
L
Linus Torvalds 已提交
3198 3199 3200 3201 3202
			pt_prev = ptype;
		}
	}

	if (pt_prev) {
D
David S. Miller 已提交
3203
		ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
L
Linus Torvalds 已提交
3204
	} else {
3205
		atomic_long_inc(&skb->dev->rx_dropped);
L
Linus Torvalds 已提交
3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216
		kfree_skb(skb);
		/* Jamal, now you will not able to escape explaining
		 * me how you were going to use this. :-)
		 */
		ret = NET_RX_DROP;
	}

out:
	rcu_read_unlock();
	return ret;
}
T
Tom Herbert 已提交
3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234

/**
 *	netif_receive_skb - process receive buffer from network
 *	@skb: buffer to process
 *
 *	netif_receive_skb() is the main receive data processing function.
 *	It always succeeds. The buffer may be dropped during processing
 *	for congestion control or by the protocol layers.
 *
 *	This function may only be called from softirq context and interrupts
 *	should be enabled.
 *
 *	Return values (usually ignored):
 *	NET_RX_SUCCESS: no congestion
 *	NET_RX_DROP: packet was dropped
 */
int netif_receive_skb(struct sk_buff *skb)
{
E
Eric Dumazet 已提交
3235 3236 3237
	if (netdev_tstamp_prequeue)
		net_timestamp_check(skb);

3238 3239 3240
	if (skb_defer_rx_timestamp(skb))
		return NET_RX_SUCCESS;

E
Eric Dumazet 已提交
3241
#ifdef CONFIG_RPS
E
Eric Dumazet 已提交
3242 3243 3244
	{
		struct rps_dev_flow voidflow, *rflow = &voidflow;
		int cpu, ret;
T
Tom Herbert 已提交
3245

E
Eric Dumazet 已提交
3246 3247 3248
		rcu_read_lock();

		cpu = get_rps_cpu(skb->dev, skb, &rflow);
T
Tom Herbert 已提交
3249

E
Eric Dumazet 已提交
3250 3251 3252 3253 3254 3255 3256
		if (cpu >= 0) {
			ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
			rcu_read_unlock();
		} else {
			rcu_read_unlock();
			ret = __netif_receive_skb(skb);
		}
T
Tom Herbert 已提交
3257

E
Eric Dumazet 已提交
3258
		return ret;
T
Tom Herbert 已提交
3259
	}
3260 3261 3262
#else
	return __netif_receive_skb(skb);
#endif
T
Tom Herbert 已提交
3263
}
E
Eric Dumazet 已提交
3264
EXPORT_SYMBOL(netif_receive_skb);
L
Linus Torvalds 已提交
3265

E
Eric Dumazet 已提交
3266 3267 3268
/* Network device is going away, flush any packets still pending
 * Called with irqs disabled.
 */
3269
static void flush_backlog(void *arg)
3270
{
3271
	struct net_device *dev = arg;
E
Eric Dumazet 已提交
3272
	struct softnet_data *sd = &__get_cpu_var(softnet_data);
3273 3274
	struct sk_buff *skb, *tmp;

E
Eric Dumazet 已提交
3275
	rps_lock(sd);
3276
	skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3277
		if (skb->dev == dev) {
E
Eric Dumazet 已提交
3278
			__skb_unlink(skb, &sd->input_pkt_queue);
3279
			kfree_skb(skb);
3280
			input_queue_head_incr(sd);
3281
		}
3282
	}
E
Eric Dumazet 已提交
3283
	rps_unlock(sd);
3284 3285 3286 3287 3288

	skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
		if (skb->dev == dev) {
			__skb_unlink(skb, &sd->process_queue);
			kfree_skb(skb);
3289
			input_queue_head_incr(sd);
3290 3291
		}
	}
3292 3293
}

3294 3295 3296 3297 3298 3299 3300
static int napi_gro_complete(struct sk_buff *skb)
{
	struct packet_type *ptype;
	__be16 type = skb->protocol;
	struct list_head *head = &ptype_base[ntohs(type) & PTYPE_HASH_MASK];
	int err = -ENOENT;

3301 3302
	if (NAPI_GRO_CB(skb)->count == 1) {
		skb_shinfo(skb)->gso_size = 0;
3303
		goto out;
3304
	}
3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325

	rcu_read_lock();
	list_for_each_entry_rcu(ptype, head, list) {
		if (ptype->type != type || ptype->dev || !ptype->gro_complete)
			continue;

		err = ptype->gro_complete(skb);
		break;
	}
	rcu_read_unlock();

	if (err) {
		WARN_ON(&ptype->list == head);
		kfree_skb(skb);
		return NET_RX_SUCCESS;
	}

out:
	return netif_receive_skb(skb);
}

E
Eric Dumazet 已提交
3326
inline void napi_gro_flush(struct napi_struct *napi)
3327 3328 3329 3330 3331 3332 3333 3334 3335
{
	struct sk_buff *skb, *next;

	for (skb = napi->gro_list; skb; skb = next) {
		next = skb->next;
		skb->next = NULL;
		napi_gro_complete(skb);
	}

3336
	napi->gro_count = 0;
3337 3338
	napi->gro_list = NULL;
}
E
Eric Dumazet 已提交
3339
EXPORT_SYMBOL(napi_gro_flush);
3340

3341
enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3342 3343 3344 3345 3346
{
	struct sk_buff **pp = NULL;
	struct packet_type *ptype;
	__be16 type = skb->protocol;
	struct list_head *head = &ptype_base[ntohs(type) & PTYPE_HASH_MASK];
H
Herbert Xu 已提交
3347
	int same_flow;
3348
	int mac_len;
3349
	enum gro_result ret;
3350

3351
	if (!(skb->dev->features & NETIF_F_GRO) || netpoll_rx_on(skb))
3352 3353
		goto normal;

3354
	if (skb_is_gso(skb) || skb_has_frag_list(skb))
3355 3356
		goto normal;

3357 3358 3359 3360 3361
	rcu_read_lock();
	list_for_each_entry_rcu(ptype, head, list) {
		if (ptype->type != type || ptype->dev || !ptype->gro_receive)
			continue;

3362
		skb_set_network_header(skb, skb_gro_offset(skb));
3363 3364 3365 3366
		mac_len = skb->network_header - skb->mac_header;
		skb->mac_len = mac_len;
		NAPI_GRO_CB(skb)->same_flow = 0;
		NAPI_GRO_CB(skb)->flush = 0;
H
Herbert Xu 已提交
3367
		NAPI_GRO_CB(skb)->free = 0;
3368 3369 3370 3371 3372 3373 3374 3375 3376

		pp = ptype->gro_receive(&napi->gro_list, skb);
		break;
	}
	rcu_read_unlock();

	if (&ptype->list == head)
		goto normal;

H
Herbert Xu 已提交
3377
	same_flow = NAPI_GRO_CB(skb)->same_flow;
3378
	ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
H
Herbert Xu 已提交
3379

3380 3381 3382 3383 3384 3385
	if (pp) {
		struct sk_buff *nskb = *pp;

		*pp = nskb->next;
		nskb->next = NULL;
		napi_gro_complete(nskb);
3386
		napi->gro_count--;
3387 3388
	}

H
Herbert Xu 已提交
3389
	if (same_flow)
3390 3391
		goto ok;

3392
	if (NAPI_GRO_CB(skb)->flush || napi->gro_count >= MAX_GRO_SKBS)
3393 3394
		goto normal;

3395
	napi->gro_count++;
3396
	NAPI_GRO_CB(skb)->count = 1;
3397
	skb_shinfo(skb)->gso_size = skb_gro_len(skb);
3398 3399
	skb->next = napi->gro_list;
	napi->gro_list = skb;
3400
	ret = GRO_HELD;
3401

3402
pull:
H
Herbert Xu 已提交
3403 3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419
	if (skb_headlen(skb) < skb_gro_offset(skb)) {
		int grow = skb_gro_offset(skb) - skb_headlen(skb);

		BUG_ON(skb->end - skb->tail < grow);

		memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);

		skb->tail += grow;
		skb->data_len -= grow;

		skb_shinfo(skb)->frags[0].page_offset += grow;
		skb_shinfo(skb)->frags[0].size -= grow;

		if (unlikely(!skb_shinfo(skb)->frags[0].size)) {
			put_page(skb_shinfo(skb)->frags[0].page);
			memmove(skb_shinfo(skb)->frags,
				skb_shinfo(skb)->frags + 1,
3420
				--skb_shinfo(skb)->nr_frags * sizeof(skb_frag_t));
H
Herbert Xu 已提交
3421
		}
3422 3423
	}

3424
ok:
3425
	return ret;
3426 3427

normal:
3428 3429
	ret = GRO_NORMAL;
	goto pull;
H
Herbert Xu 已提交
3430
}
3431 3432
EXPORT_SYMBOL(dev_gro_receive);

3433
static inline gro_result_t
3434
__napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3435 3436 3437 3438
{
	struct sk_buff *p;

	for (p = napi->gro_list; p; p = p->next) {
3439 3440 3441
		unsigned long diffs;

		diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
3442
		diffs |= p->vlan_tci ^ skb->vlan_tci;
3443
		diffs |= compare_ether_header(skb_mac_header(p),
3444
					      skb_gro_mac_header(skb));
3445
		NAPI_GRO_CB(p)->same_flow = !diffs;
3446 3447 3448 3449 3450
		NAPI_GRO_CB(p)->flush = 0;
	}

	return dev_gro_receive(napi, skb);
}
H
Herbert Xu 已提交
3451

3452
gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
H
Herbert Xu 已提交
3453
{
3454 3455
	switch (ret) {
	case GRO_NORMAL:
3456 3457 3458
		if (netif_receive_skb(skb))
			ret = GRO_DROP;
		break;
H
Herbert Xu 已提交
3459

3460 3461
	case GRO_DROP:
	case GRO_MERGED_FREE:
H
Herbert Xu 已提交
3462 3463
		kfree_skb(skb);
		break;
3464 3465 3466 3467

	case GRO_HELD:
	case GRO_MERGED:
		break;
H
Herbert Xu 已提交
3468 3469
	}

3470
	return ret;
3471 3472 3473
}
EXPORT_SYMBOL(napi_skb_finish);

3474 3475 3476 3477
void skb_gro_reset_offset(struct sk_buff *skb)
{
	NAPI_GRO_CB(skb)->data_offset = 0;
	NAPI_GRO_CB(skb)->frag0 = NULL;
3478
	NAPI_GRO_CB(skb)->frag0_len = 0;
3479

3480
	if (skb->mac_header == skb->tail &&
3481
	    !PageHighMem(skb_shinfo(skb)->frags[0].page)) {
3482 3483 3484
		NAPI_GRO_CB(skb)->frag0 =
			page_address(skb_shinfo(skb)->frags[0].page) +
			skb_shinfo(skb)->frags[0].page_offset;
3485 3486
		NAPI_GRO_CB(skb)->frag0_len = skb_shinfo(skb)->frags[0].size;
	}
3487 3488 3489
}
EXPORT_SYMBOL(skb_gro_reset_offset);

3490
gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3491
{
3492 3493
	skb_gro_reset_offset(skb);

3494
	return napi_skb_finish(__napi_gro_receive(napi, skb), skb);
3495 3496 3497
}
EXPORT_SYMBOL(napi_gro_receive);

S
stephen hemminger 已提交
3498
static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
3499 3500 3501
{
	__skb_pull(skb, skb_headlen(skb));
	skb_reserve(skb, NET_IP_ALIGN - skb_headroom(skb));
3502
	skb->vlan_tci = 0;
H
Herbert Xu 已提交
3503
	skb->dev = napi->dev;
A
Andy Gospodarek 已提交
3504
	skb->skb_iif = 0;
3505 3506 3507 3508

	napi->skb = skb;
}

3509
struct sk_buff *napi_get_frags(struct napi_struct *napi)
H
Herbert Xu 已提交
3510 3511 3512 3513
{
	struct sk_buff *skb = napi->skb;

	if (!skb) {
3514 3515 3516
		skb = netdev_alloc_skb_ip_align(napi->dev, GRO_MAX_HEAD);
		if (skb)
			napi->skb = skb;
3517
	}
3518 3519
	return skb;
}
3520
EXPORT_SYMBOL(napi_get_frags);
3521

3522 3523
gro_result_t napi_frags_finish(struct napi_struct *napi, struct sk_buff *skb,
			       gro_result_t ret)
3524
{
3525 3526
	switch (ret) {
	case GRO_NORMAL:
3527
	case GRO_HELD:
3528
		skb->protocol = eth_type_trans(skb, skb->dev);
3529

3530 3531 3532 3533
		if (ret == GRO_HELD)
			skb_gro_pull(skb, -ETH_HLEN);
		else if (netif_receive_skb(skb))
			ret = GRO_DROP;
3534
		break;
H
Herbert Xu 已提交
3535

3536 3537 3538 3539
	case GRO_DROP:
	case GRO_MERGED_FREE:
		napi_reuse_skb(napi, skb);
		break;
3540 3541 3542

	case GRO_MERGED:
		break;
3543
	}
H
Herbert Xu 已提交
3544

3545
	return ret;
H
Herbert Xu 已提交
3546
}
3547 3548
EXPORT_SYMBOL(napi_frags_finish);

3549 3550 3551 3552
struct sk_buff *napi_frags_skb(struct napi_struct *napi)
{
	struct sk_buff *skb = napi->skb;
	struct ethhdr *eth;
3553 3554
	unsigned int hlen;
	unsigned int off;
3555 3556 3557 3558 3559 3560

	napi->skb = NULL;

	skb_reset_mac_header(skb);
	skb_gro_reset_offset(skb);

3561 3562 3563 3564 3565 3566 3567 3568 3569 3570
	off = skb_gro_offset(skb);
	hlen = off + sizeof(*eth);
	eth = skb_gro_header_fast(skb, off);
	if (skb_gro_header_hard(skb, hlen)) {
		eth = skb_gro_header_slow(skb, hlen, off);
		if (unlikely(!eth)) {
			napi_reuse_skb(napi, skb);
			skb = NULL;
			goto out;
		}
3571 3572 3573 3574 3575 3576 3577 3578 3579 3580 3581 3582 3583 3584 3585
	}

	skb_gro_pull(skb, sizeof(*eth));

	/*
	 * This works because the only protocols we care about don't require
	 * special handling.  We'll fix it up properly at the end.
	 */
	skb->protocol = eth->h_proto;

out:
	return skb;
}
EXPORT_SYMBOL(napi_frags_skb);

3586
gro_result_t napi_gro_frags(struct napi_struct *napi)
3587
{
3588
	struct sk_buff *skb = napi_frags_skb(napi);
3589 3590

	if (!skb)
3591
		return GRO_DROP;
3592 3593 3594

	return napi_frags_finish(napi, skb, __napi_gro_receive(napi, skb));
}
H
Herbert Xu 已提交
3595 3596
EXPORT_SYMBOL(napi_gro_frags);

3597 3598 3599 3600 3601 3602 3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613 3614 3615 3616 3617 3618 3619 3620 3621 3622 3623 3624
/*
 * net_rps_action sends any pending IPI's for rps.
 * Note: called with local irq disabled, but exits with local irq enabled.
 */
static void net_rps_action_and_irq_enable(struct softnet_data *sd)
{
#ifdef CONFIG_RPS
	struct softnet_data *remsd = sd->rps_ipi_list;

	if (remsd) {
		sd->rps_ipi_list = NULL;

		local_irq_enable();

		/* Send pending IPI's to kick RPS processing on remote cpus. */
		while (remsd) {
			struct softnet_data *next = remsd->rps_ipi_next;

			if (cpu_online(remsd->cpu))
				__smp_call_function_single(remsd->cpu,
							   &remsd->csd, 0);
			remsd = next;
		}
	} else
#endif
		local_irq_enable();
}

3625
static int process_backlog(struct napi_struct *napi, int quota)
L
Linus Torvalds 已提交
3626 3627
{
	int work = 0;
E
Eric Dumazet 已提交
3628
	struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
L
Linus Torvalds 已提交
3629

3630 3631 3632 3633 3634 3635 3636 3637 3638
#ifdef CONFIG_RPS
	/* Check if we have pending ipi, its better to send them now,
	 * not waiting net_rx_action() end.
	 */
	if (sd->rps_ipi_list) {
		local_irq_disable();
		net_rps_action_and_irq_enable(sd);
	}
#endif
3639
	napi->weight = weight_p;
3640 3641
	local_irq_disable();
	while (work < quota) {
L
Linus Torvalds 已提交
3642
		struct sk_buff *skb;
3643 3644 3645 3646 3647 3648
		unsigned int qlen;

		while ((skb = __skb_dequeue(&sd->process_queue))) {
			local_irq_enable();
			__netif_receive_skb(skb);
			local_irq_disable();
3649 3650 3651 3652 3653
			input_queue_head_incr(sd);
			if (++work >= quota) {
				local_irq_enable();
				return work;
			}
3654
		}
L
Linus Torvalds 已提交
3655

E
Eric Dumazet 已提交
3656
		rps_lock(sd);
3657
		qlen = skb_queue_len(&sd->input_pkt_queue);
3658
		if (qlen)
3659 3660
			skb_queue_splice_tail_init(&sd->input_pkt_queue,
						   &sd->process_queue);
3661

3662
		if (qlen < quota - work) {
E
Eric Dumazet 已提交
3663 3664 3665 3666 3667 3668 3669 3670 3671 3672
			/*
			 * Inline a custom version of __napi_complete().
			 * only current cpu owns and manipulates this napi,
			 * and NAPI_STATE_SCHED is the only possible flag set on backlog.
			 * we can use a plain write instead of clear_bit(),
			 * and we dont need an smp_mb() memory barrier.
			 */
			list_del(&napi->poll_list);
			napi->state = 0;

3673
			quota = work + qlen;
3674
		}
E
Eric Dumazet 已提交
3675
		rps_unlock(sd);
3676 3677
	}
	local_irq_enable();
L
Linus Torvalds 已提交
3678

3679 3680
	return work;
}
L
Linus Torvalds 已提交
3681

3682 3683
/**
 * __napi_schedule - schedule for receive
3684
 * @n: entry to schedule
3685 3686 3687
 *
 * The entry's receive function will be scheduled to run
 */
H
Harvey Harrison 已提交
3688
void __napi_schedule(struct napi_struct *n)
3689 3690
{
	unsigned long flags;
L
Linus Torvalds 已提交
3691

3692
	local_irq_save(flags);
E
Eric Dumazet 已提交
3693
	____napi_schedule(&__get_cpu_var(softnet_data), n);
3694
	local_irq_restore(flags);
L
Linus Torvalds 已提交
3695
}
3696 3697
EXPORT_SYMBOL(__napi_schedule);

3698 3699 3700 3701 3702 3703 3704 3705 3706 3707 3708 3709 3710 3711 3712 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723 3724 3725 3726 3727 3728 3729 3730
void __napi_complete(struct napi_struct *n)
{
	BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
	BUG_ON(n->gro_list);

	list_del(&n->poll_list);
	smp_mb__before_clear_bit();
	clear_bit(NAPI_STATE_SCHED, &n->state);
}
EXPORT_SYMBOL(__napi_complete);

void napi_complete(struct napi_struct *n)
{
	unsigned long flags;

	/*
	 * don't let napi dequeue from the cpu poll list
	 * just in case its running on a different cpu
	 */
	if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
		return;

	napi_gro_flush(n);
	local_irq_save(flags);
	__napi_complete(n);
	local_irq_restore(flags);
}
EXPORT_SYMBOL(napi_complete);

void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
		    int (*poll)(struct napi_struct *, int), int weight)
{
	INIT_LIST_HEAD(&napi->poll_list);
3731
	napi->gro_count = 0;
3732
	napi->gro_list = NULL;
H
Herbert Xu 已提交
3733
	napi->skb = NULL;
3734 3735 3736 3737
	napi->poll = poll;
	napi->weight = weight;
	list_add(&napi->dev_list, &dev->napi_list);
	napi->dev = dev;
H
Herbert Xu 已提交
3738
#ifdef CONFIG_NETPOLL
3739 3740 3741 3742 3743 3744 3745 3746 3747 3748 3749
	spin_lock_init(&napi->poll_lock);
	napi->poll_owner = -1;
#endif
	set_bit(NAPI_STATE_SCHED, &napi->state);
}
EXPORT_SYMBOL(netif_napi_add);

void netif_napi_del(struct napi_struct *napi)
{
	struct sk_buff *skb, *next;

3750
	list_del_init(&napi->dev_list);
3751
	napi_free_frags(napi);
3752 3753 3754 3755 3756 3757 3758 3759

	for (skb = napi->gro_list; skb; skb = next) {
		next = skb->next;
		skb->next = NULL;
		kfree_skb(skb);
	}

	napi->gro_list = NULL;
3760
	napi->gro_count = 0;
3761 3762 3763
}
EXPORT_SYMBOL(netif_napi_del);

L
Linus Torvalds 已提交
3764 3765
static void net_rx_action(struct softirq_action *h)
{
3766
	struct softnet_data *sd = &__get_cpu_var(softnet_data);
3767
	unsigned long time_limit = jiffies + 2;
3768
	int budget = netdev_budget;
3769 3770
	void *have;

L
Linus Torvalds 已提交
3771 3772
	local_irq_disable();

3773
	while (!list_empty(&sd->poll_list)) {
3774 3775
		struct napi_struct *n;
		int work, weight;
L
Linus Torvalds 已提交
3776

3777
		/* If softirq window is exhuasted then punt.
3778 3779
		 * Allow this to run for 2 jiffies since which will allow
		 * an average latency of 1.5/HZ.
3780
		 */
3781
		if (unlikely(budget <= 0 || time_after(jiffies, time_limit)))
L
Linus Torvalds 已提交
3782 3783 3784 3785
			goto softnet_break;

		local_irq_enable();

3786 3787 3788 3789 3790
		/* Even though interrupts have been re-enabled, this
		 * access is safe because interrupts can only add new
		 * entries to the tail of this list, and only ->poll()
		 * calls can remove this head entry from the list.
		 */
3791
		n = list_first_entry(&sd->poll_list, struct napi_struct, poll_list);
L
Linus Torvalds 已提交
3792

3793 3794 3795 3796
		have = netpoll_poll_lock(n);

		weight = n->weight;

3797 3798 3799 3800
		/* This NAPI_STATE_SCHED test is for avoiding a race
		 * with netpoll's poll_napi().  Only the entity which
		 * obtains the lock and sees NAPI_STATE_SCHED set will
		 * actually make the ->poll() call.  Therefore we avoid
L
Lucas De Marchi 已提交
3801
		 * accidentally calling ->poll() when NAPI is not scheduled.
3802 3803
		 */
		work = 0;
3804
		if (test_bit(NAPI_STATE_SCHED, &n->state)) {
3805
			work = n->poll(n, weight);
3806 3807
			trace_napi_poll(n);
		}
3808 3809 3810 3811 3812 3813 3814 3815 3816 3817 3818 3819

		WARN_ON_ONCE(work > weight);

		budget -= work;

		local_irq_disable();

		/* Drivers must not modify the NAPI state if they
		 * consume the entire weight.  In such cases this code
		 * still "owns" the NAPI instance and therefore can
		 * move the instance around on the list at-will.
		 */
3820
		if (unlikely(work == weight)) {
3821 3822 3823 3824 3825
			if (unlikely(napi_disable_pending(n))) {
				local_irq_enable();
				napi_complete(n);
				local_irq_disable();
			} else
3826
				list_move_tail(&n->poll_list, &sd->poll_list);
3827
		}
3828 3829

		netpoll_poll_unlock(have);
L
Linus Torvalds 已提交
3830 3831
	}
out:
3832
	net_rps_action_and_irq_enable(sd);
T
Tom Herbert 已提交
3833

3834 3835 3836 3837 3838
#ifdef CONFIG_NET_DMA
	/*
	 * There may not be any more sk_buffs coming right now, so push
	 * any pending DMA copies to hardware
	 */
3839
	dma_issue_pending_all();
3840
#endif
3841

L
Linus Torvalds 已提交
3842 3843 3844
	return;

softnet_break:
C
Changli Gao 已提交
3845
	sd->time_squeeze++;
L
Linus Torvalds 已提交
3846 3847 3848 3849
	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
	goto out;
}

E
Eric Dumazet 已提交
3850
static gifconf_func_t *gifconf_list[NPROTO];
L
Linus Torvalds 已提交
3851 3852 3853 3854 3855 3856 3857 3858 3859 3860

/**
 *	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.
 */
E
Eric Dumazet 已提交
3861
int register_gifconf(unsigned int family, gifconf_func_t *gifconf)
L
Linus Torvalds 已提交
3862 3863 3864 3865 3866 3867
{
	if (family >= NPROTO)
		return -EINVAL;
	gifconf_list[family] = gifconf;
	return 0;
}
E
Eric Dumazet 已提交
3868
EXPORT_SYMBOL(register_gifconf);
L
Linus Torvalds 已提交
3869 3870 3871 3872 3873 3874 3875 3876 3877 3878 3879 3880 3881


/*
 *	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
 */

3882
static int dev_ifname(struct net *net, struct ifreq __user *arg)
L
Linus Torvalds 已提交
3883 3884 3885 3886 3887 3888 3889 3890 3891 3892 3893
{
	struct net_device *dev;
	struct ifreq ifr;

	/*
	 *	Fetch the caller's info block.
	 */

	if (copy_from_user(&ifr, arg, sizeof(struct ifreq)))
		return -EFAULT;

3894 3895
	rcu_read_lock();
	dev = dev_get_by_index_rcu(net, ifr.ifr_ifindex);
L
Linus Torvalds 已提交
3896
	if (!dev) {
3897
		rcu_read_unlock();
L
Linus Torvalds 已提交
3898 3899 3900 3901
		return -ENODEV;
	}

	strcpy(ifr.ifr_name, dev->name);
3902
	rcu_read_unlock();
L
Linus Torvalds 已提交
3903 3904 3905 3906 3907 3908 3909 3910 3911 3912 3913 3914

	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'.
 */

3915
static int dev_ifconf(struct net *net, char __user *arg)
L
Linus Torvalds 已提交
3916 3917 3918 3919 3920 3921 3922 3923 3924 3925 3926 3927 3928 3929 3930 3931 3932 3933 3934 3935 3936 3937 3938
{
	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;
3939
	for_each_netdev(net, dev) {
L
Linus Torvalds 已提交
3940 3941 3942 3943 3944 3945 3946 3947 3948 3949 3950 3951 3952
		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;
			}
		}
3953
	}
L
Linus Torvalds 已提交
3954 3955 3956 3957 3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968 3969 3970

	/*
	 *	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
/*
 *	This is invoked by the /proc filesystem handler to display a device
 *	in detail.
 */
3971
void *dev_seq_start(struct seq_file *seq, loff_t *pos)
3972
	__acquires(RCU)
L
Linus Torvalds 已提交
3973
{
3974
	struct net *net = seq_file_net(seq);
3975
	loff_t off;
L
Linus Torvalds 已提交
3976 3977
	struct net_device *dev;

3978
	rcu_read_lock();
3979 3980
	if (!*pos)
		return SEQ_START_TOKEN;
L
Linus Torvalds 已提交
3981

3982
	off = 1;
3983
	for_each_netdev_rcu(net, dev)
3984 3985
		if (off++ == *pos)
			return dev;
L
Linus Torvalds 已提交
3986

3987
	return NULL;
L
Linus Torvalds 已提交
3988 3989 3990 3991
}

void *dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
E
Eric Dumazet 已提交
3992 3993 3994 3995 3996 3997
	struct net_device *dev = v;

	if (v == SEQ_START_TOKEN)
		dev = first_net_device_rcu(seq_file_net(seq));
	else
		dev = next_net_device_rcu(dev);
3998

L
Linus Torvalds 已提交
3999
	++*pos;
E
Eric Dumazet 已提交
4000
	return dev;
L
Linus Torvalds 已提交
4001 4002 4003
}

void dev_seq_stop(struct seq_file *seq, void *v)
4004
	__releases(RCU)
L
Linus Torvalds 已提交
4005
{
4006
	rcu_read_unlock();
L
Linus Torvalds 已提交
4007 4008 4009 4010
}

static void dev_seq_printf_stats(struct seq_file *seq, struct net_device *dev)
{
4011 4012
	struct rtnl_link_stats64 temp;
	const struct rtnl_link_stats64 *stats = dev_get_stats(dev, &temp);
L
Linus Torvalds 已提交
4013

4014 4015
	seq_printf(seq, "%6s: %7llu %7llu %4llu %4llu %4llu %5llu %10llu %9llu "
		   "%8llu %7llu %4llu %4llu %4llu %5llu %7llu %10llu\n",
4016 4017 4018 4019 4020 4021 4022 4023 4024 4025 4026 4027 4028 4029 4030
		   dev->name, stats->rx_bytes, stats->rx_packets,
		   stats->rx_errors,
		   stats->rx_dropped + stats->rx_missed_errors,
		   stats->rx_fifo_errors,
		   stats->rx_length_errors + stats->rx_over_errors +
		    stats->rx_crc_errors + stats->rx_frame_errors,
		   stats->rx_compressed, stats->multicast,
		   stats->tx_bytes, stats->tx_packets,
		   stats->tx_errors, stats->tx_dropped,
		   stats->tx_fifo_errors, stats->collisions,
		   stats->tx_carrier_errors +
		    stats->tx_aborted_errors +
		    stats->tx_window_errors +
		    stats->tx_heartbeat_errors,
		   stats->tx_compressed);
L
Linus Torvalds 已提交
4031 4032 4033 4034 4035 4036 4037 4038 4039 4040 4041 4042 4043 4044 4045 4046 4047 4048 4049
}

/*
 *	Called from the PROCfs module. This now uses the new arbitrary sized
 *	/proc/net interface to create /proc/net/dev
 */
static int dev_seq_show(struct seq_file *seq, void *v)
{
	if (v == SEQ_START_TOKEN)
		seq_puts(seq, "Inter-|   Receive                            "
			      "                    |  Transmit\n"
			      " face |bytes    packets errs drop fifo frame "
			      "compressed multicast|bytes    packets errs "
			      "drop fifo colls carrier compressed\n");
	else
		dev_seq_printf_stats(seq, v);
	return 0;
}

C
Changli Gao 已提交
4050
static struct softnet_data *softnet_get_online(loff_t *pos)
L
Linus Torvalds 已提交
4051
{
C
Changli Gao 已提交
4052
	struct softnet_data *sd = NULL;
L
Linus Torvalds 已提交
4053

4054
	while (*pos < nr_cpu_ids)
4055
		if (cpu_online(*pos)) {
C
Changli Gao 已提交
4056
			sd = &per_cpu(softnet_data, *pos);
L
Linus Torvalds 已提交
4057 4058 4059
			break;
		} else
			++*pos;
C
Changli Gao 已提交
4060
	return sd;
L
Linus Torvalds 已提交
4061 4062 4063 4064 4065 4066 4067 4068 4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079
}

static void *softnet_seq_start(struct seq_file *seq, loff_t *pos)
{
	return softnet_get_online(pos);
}

static void *softnet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
	++*pos;
	return softnet_get_online(pos);
}

static void softnet_seq_stop(struct seq_file *seq, void *v)
{
}

static int softnet_seq_show(struct seq_file *seq, void *v)
{
C
Changli Gao 已提交
4080
	struct softnet_data *sd = v;
L
Linus Torvalds 已提交
4081

T
Tom Herbert 已提交
4082
	seq_printf(seq, "%08x %08x %08x %08x %08x %08x %08x %08x %08x %08x\n",
C
Changli Gao 已提交
4083
		   sd->processed, sd->dropped, sd->time_squeeze, 0,
4084
		   0, 0, 0, 0, /* was fastroute */
C
Changli Gao 已提交
4085
		   sd->cpu_collision, sd->received_rps);
L
Linus Torvalds 已提交
4086 4087 4088
	return 0;
}

4089
static const struct seq_operations dev_seq_ops = {
L
Linus Torvalds 已提交
4090 4091 4092 4093 4094 4095 4096 4097
	.start = dev_seq_start,
	.next  = dev_seq_next,
	.stop  = dev_seq_stop,
	.show  = dev_seq_show,
};

static int dev_seq_open(struct inode *inode, struct file *file)
{
4098 4099
	return seq_open_net(inode, file, &dev_seq_ops,
			    sizeof(struct seq_net_private));
L
Linus Torvalds 已提交
4100 4101
}

4102
static const struct file_operations dev_seq_fops = {
L
Linus Torvalds 已提交
4103 4104 4105 4106
	.owner	 = THIS_MODULE,
	.open    = dev_seq_open,
	.read    = seq_read,
	.llseek  = seq_lseek,
4107
	.release = seq_release_net,
L
Linus Torvalds 已提交
4108 4109
};

4110
static const struct seq_operations softnet_seq_ops = {
L
Linus Torvalds 已提交
4111 4112 4113 4114 4115 4116 4117 4118 4119 4120 4121
	.start = softnet_seq_start,
	.next  = softnet_seq_next,
	.stop  = softnet_seq_stop,
	.show  = softnet_seq_show,
};

static int softnet_seq_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &softnet_seq_ops);
}

4122
static const struct file_operations softnet_seq_fops = {
L
Linus Torvalds 已提交
4123 4124 4125 4126 4127 4128 4129
	.owner	 = THIS_MODULE,
	.open    = softnet_seq_open,
	.read    = seq_read,
	.llseek  = seq_lseek,
	.release = seq_release,
};

4130 4131 4132 4133 4134 4135 4136 4137 4138 4139 4140 4141
static void *ptype_get_idx(loff_t pos)
{
	struct packet_type *pt = NULL;
	loff_t i = 0;
	int t;

	list_for_each_entry_rcu(pt, &ptype_all, list) {
		if (i == pos)
			return pt;
		++i;
	}

4142
	for (t = 0; t < PTYPE_HASH_SIZE; t++) {
4143 4144 4145 4146 4147 4148 4149 4150 4151 4152
		list_for_each_entry_rcu(pt, &ptype_base[t], list) {
			if (i == pos)
				return pt;
			++i;
		}
	}
	return NULL;
}

static void *ptype_seq_start(struct seq_file *seq, loff_t *pos)
4153
	__acquires(RCU)
4154 4155 4156 4157 4158 4159 4160 4161 4162 4163 4164 4165 4166 4167 4168 4169 4170 4171 4172 4173 4174 4175 4176
{
	rcu_read_lock();
	return *pos ? ptype_get_idx(*pos - 1) : SEQ_START_TOKEN;
}

static void *ptype_seq_next(struct seq_file *seq, void *v, loff_t *pos)
{
	struct packet_type *pt;
	struct list_head *nxt;
	int hash;

	++*pos;
	if (v == SEQ_START_TOKEN)
		return ptype_get_idx(0);

	pt = v;
	nxt = pt->list.next;
	if (pt->type == htons(ETH_P_ALL)) {
		if (nxt != &ptype_all)
			goto found;
		hash = 0;
		nxt = ptype_base[0].next;
	} else
4177
		hash = ntohs(pt->type) & PTYPE_HASH_MASK;
4178 4179

	while (nxt == &ptype_base[hash]) {
4180
		if (++hash >= PTYPE_HASH_SIZE)
4181 4182 4183 4184 4185 4186 4187 4188
			return NULL;
		nxt = ptype_base[hash].next;
	}
found:
	return list_entry(nxt, struct packet_type, list);
}

static void ptype_seq_stop(struct seq_file *seq, void *v)
4189
	__releases(RCU)
4190 4191 4192 4193 4194 4195 4196 4197 4198 4199
{
	rcu_read_unlock();
}

static int ptype_seq_show(struct seq_file *seq, void *v)
{
	struct packet_type *pt = v;

	if (v == SEQ_START_TOKEN)
		seq_puts(seq, "Type Device      Function\n");
4200
	else if (pt->dev == NULL || dev_net(pt->dev) == seq_file_net(seq)) {
4201 4202 4203 4204 4205
		if (pt->type == htons(ETH_P_ALL))
			seq_puts(seq, "ALL ");
		else
			seq_printf(seq, "%04x", ntohs(pt->type));

A
Alexey Dobriyan 已提交
4206 4207
		seq_printf(seq, " %-8s %pF\n",
			   pt->dev ? pt->dev->name : "", pt->func);
4208 4209 4210 4211 4212 4213 4214 4215 4216 4217 4218 4219 4220 4221
	}

	return 0;
}

static const struct seq_operations ptype_seq_ops = {
	.start = ptype_seq_start,
	.next  = ptype_seq_next,
	.stop  = ptype_seq_stop,
	.show  = ptype_seq_show,
};

static int ptype_seq_open(struct inode *inode, struct file *file)
{
4222 4223
	return seq_open_net(inode, file, &ptype_seq_ops,
			sizeof(struct seq_net_private));
4224 4225 4226 4227 4228 4229 4230
}

static const struct file_operations ptype_seq_fops = {
	.owner	 = THIS_MODULE,
	.open    = ptype_seq_open,
	.read    = seq_read,
	.llseek  = seq_lseek,
4231
	.release = seq_release_net,
4232 4233 4234
};


4235
static int __net_init dev_proc_net_init(struct net *net)
L
Linus Torvalds 已提交
4236 4237 4238
{
	int rc = -ENOMEM;

4239
	if (!proc_net_fops_create(net, "dev", S_IRUGO, &dev_seq_fops))
L
Linus Torvalds 已提交
4240
		goto out;
4241
	if (!proc_net_fops_create(net, "softnet_stat", S_IRUGO, &softnet_seq_fops))
L
Linus Torvalds 已提交
4242
		goto out_dev;
4243
	if (!proc_net_fops_create(net, "ptype", S_IRUGO, &ptype_seq_fops))
4244
		goto out_softnet;
4245

4246
	if (wext_proc_init(net))
4247
		goto out_ptype;
L
Linus Torvalds 已提交
4248 4249 4250
	rc = 0;
out:
	return rc;
4251
out_ptype:
4252
	proc_net_remove(net, "ptype");
L
Linus Torvalds 已提交
4253
out_softnet:
4254
	proc_net_remove(net, "softnet_stat");
L
Linus Torvalds 已提交
4255
out_dev:
4256
	proc_net_remove(net, "dev");
L
Linus Torvalds 已提交
4257 4258
	goto out;
}
4259

4260
static void __net_exit dev_proc_net_exit(struct net *net)
4261 4262 4263 4264 4265 4266 4267 4268
{
	wext_proc_exit(net);

	proc_net_remove(net, "ptype");
	proc_net_remove(net, "softnet_stat");
	proc_net_remove(net, "dev");
}

4269
static struct pernet_operations __net_initdata dev_proc_ops = {
4270 4271 4272 4273 4274 4275 4276 4277
	.init = dev_proc_net_init,
	.exit = dev_proc_net_exit,
};

static int __init dev_proc_init(void)
{
	return register_pernet_subsys(&dev_proc_ops);
}
L
Linus Torvalds 已提交
4278 4279 4280 4281 4282 4283
#else
#define dev_proc_init() 0
#endif	/* CONFIG_PROC_FS */


/**
J
Jiri Pirko 已提交
4284
 *	netdev_set_master	-	set up master pointer
L
Linus Torvalds 已提交
4285 4286 4287 4288 4289 4290
 *	@slave: slave device
 *	@master: new master device
 *
 *	Changes the master device of the slave. Pass %NULL to break the
 *	bonding. The caller must hold the RTNL semaphore. On a failure
 *	a negative errno code is returned. On success the reference counts
J
Jiri Pirko 已提交
4291
 *	are adjusted and the function returns zero.
L
Linus Torvalds 已提交
4292 4293 4294 4295 4296 4297 4298 4299 4300 4301 4302 4303 4304 4305
 */
int netdev_set_master(struct net_device *slave, struct net_device *master)
{
	struct net_device *old = slave->master;

	ASSERT_RTNL();

	if (master) {
		if (old)
			return -EBUSY;
		dev_hold(master);
	}

	slave->master = master;
4306

4307
	if (old)
L
Linus Torvalds 已提交
4308
		dev_put(old);
J
Jiri Pirko 已提交
4309 4310 4311 4312 4313 4314 4315 4316 4317 4318 4319 4320 4321 4322 4323 4324 4325 4326 4327 4328 4329 4330 4331
	return 0;
}
EXPORT_SYMBOL(netdev_set_master);

/**
 *	netdev_set_bond_master	-	set up bonding master/slave pair
 *	@slave: slave device
 *	@master: new master device
 *
 *	Changes the master device of the slave. Pass %NULL to break the
 *	bonding. The caller must hold the RTNL semaphore. On a failure
 *	a negative errno code is returned. On success %RTM_NEWLINK is sent
 *	to the routing socket and the function returns zero.
 */
int netdev_set_bond_master(struct net_device *slave, struct net_device *master)
{
	int err;

	ASSERT_RTNL();

	err = netdev_set_master(slave, master);
	if (err)
		return err;
L
Linus Torvalds 已提交
4332 4333 4334 4335 4336 4337 4338 4339
	if (master)
		slave->flags |= IFF_SLAVE;
	else
		slave->flags &= ~IFF_SLAVE;

	rtmsg_ifinfo(RTM_NEWLINK, slave, IFF_SLAVE);
	return 0;
}
J
Jiri Pirko 已提交
4340
EXPORT_SYMBOL(netdev_set_bond_master);
L
Linus Torvalds 已提交
4341

4342 4343
static void dev_change_rx_flags(struct net_device *dev, int flags)
{
4344 4345 4346 4347
	const struct net_device_ops *ops = dev->netdev_ops;

	if ((dev->flags & IFF_UP) && ops->ndo_change_rx_flags)
		ops->ndo_change_rx_flags(dev, flags);
4348 4349
}

4350
static int __dev_set_promiscuity(struct net_device *dev, int inc)
L
Linus Torvalds 已提交
4351 4352
{
	unsigned short old_flags = dev->flags;
4353 4354
	uid_t uid;
	gid_t gid;
L
Linus Torvalds 已提交
4355

4356 4357
	ASSERT_RTNL();

4358 4359 4360 4361 4362 4363 4364 4365 4366 4367 4368 4369 4370 4371 4372 4373 4374
	dev->flags |= IFF_PROMISC;
	dev->promiscuity += inc;
	if (dev->promiscuity == 0) {
		/*
		 * Avoid overflow.
		 * If inc causes overflow, untouch promisc and return error.
		 */
		if (inc < 0)
			dev->flags &= ~IFF_PROMISC;
		else {
			dev->promiscuity -= inc;
			printk(KERN_WARNING "%s: promiscuity touches roof, "
				"set promiscuity failed, promiscuity feature "
				"of device might be broken.\n", dev->name);
			return -EOVERFLOW;
		}
	}
4375
	if (dev->flags != old_flags) {
L
Linus Torvalds 已提交
4376 4377
		printk(KERN_INFO "device %s %s promiscuous mode\n",
		       dev->name, (dev->flags & IFF_PROMISC) ? "entered" :
4378
							       "left");
4379 4380
		if (audit_enabled) {
			current_uid_gid(&uid, &gid);
4381 4382 4383 4384 4385 4386
			audit_log(current->audit_context, GFP_ATOMIC,
				AUDIT_ANOM_PROMISCUOUS,
				"dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
				dev->name, (dev->flags & IFF_PROMISC),
				(old_flags & IFF_PROMISC),
				audit_get_loginuid(current),
4387
				uid, gid,
4388
				audit_get_sessionid(current));
4389
		}
4390

4391
		dev_change_rx_flags(dev, IFF_PROMISC);
L
Linus Torvalds 已提交
4392
	}
4393
	return 0;
L
Linus Torvalds 已提交
4394 4395
}

4396 4397 4398 4399 4400 4401 4402 4403 4404
/**
 *	dev_set_promiscuity	- update promiscuity count on a device
 *	@dev: device
 *	@inc: modifier
 *
 *	Add or remove promiscuity from a device. While the count in the device
 *	remains above zero the interface remains promiscuous. Once it hits zero
 *	the device reverts back to normal filtering operation. A negative inc
 *	value is used to drop promiscuity on the device.
4405
 *	Return 0 if successful or a negative errno code on error.
4406
 */
4407
int dev_set_promiscuity(struct net_device *dev, int inc)
4408 4409
{
	unsigned short old_flags = dev->flags;
4410
	int err;
4411

4412
	err = __dev_set_promiscuity(dev, inc);
4413
	if (err < 0)
4414
		return err;
4415 4416
	if (dev->flags != old_flags)
		dev_set_rx_mode(dev);
4417
	return err;
4418
}
E
Eric Dumazet 已提交
4419
EXPORT_SYMBOL(dev_set_promiscuity);
4420

L
Linus Torvalds 已提交
4421 4422 4423 4424 4425 4426 4427 4428 4429 4430
/**
 *	dev_set_allmulti	- update allmulti count on a device
 *	@dev: device
 *	@inc: modifier
 *
 *	Add or remove reception of all multicast frames to a device. While the
 *	count in the device remains above zero the interface remains listening
 *	to all interfaces. Once it hits zero the device reverts back to normal
 *	filtering operation. A negative @inc value is used to drop the counter
 *	when releasing a resource needing all multicasts.
4431
 *	Return 0 if successful or a negative errno code on error.
L
Linus Torvalds 已提交
4432 4433
 */

4434
int dev_set_allmulti(struct net_device *dev, int inc)
L
Linus Torvalds 已提交
4435 4436 4437
{
	unsigned short old_flags = dev->flags;

4438 4439
	ASSERT_RTNL();

L
Linus Torvalds 已提交
4440
	dev->flags |= IFF_ALLMULTI;
4441 4442 4443 4444 4445 4446 4447 4448 4449 4450 4451 4452 4453 4454 4455 4456
	dev->allmulti += inc;
	if (dev->allmulti == 0) {
		/*
		 * Avoid overflow.
		 * If inc causes overflow, untouch allmulti and return error.
		 */
		if (inc < 0)
			dev->flags &= ~IFF_ALLMULTI;
		else {
			dev->allmulti -= inc;
			printk(KERN_WARNING "%s: allmulti touches roof, "
				"set allmulti failed, allmulti feature of "
				"device might be broken.\n", dev->name);
			return -EOVERFLOW;
		}
	}
4457
	if (dev->flags ^ old_flags) {
4458
		dev_change_rx_flags(dev, IFF_ALLMULTI);
4459
		dev_set_rx_mode(dev);
4460
	}
4461
	return 0;
4462
}
E
Eric Dumazet 已提交
4463
EXPORT_SYMBOL(dev_set_allmulti);
4464 4465 4466 4467

/*
 *	Upload unicast and multicast address lists to device and
 *	configure RX filtering. When the device doesn't support unicast
J
Joe Perches 已提交
4468
 *	filtering it is put in promiscuous mode while unicast addresses
4469 4470 4471 4472
 *	are present.
 */
void __dev_set_rx_mode(struct net_device *dev)
{
4473 4474
	const struct net_device_ops *ops = dev->netdev_ops;

4475 4476 4477 4478 4479
	/* dev_open will call this function so the list will stay sane. */
	if (!(dev->flags&IFF_UP))
		return;

	if (!netif_device_present(dev))
4480
		return;
4481

4482 4483
	if (ops->ndo_set_rx_mode)
		ops->ndo_set_rx_mode(dev);
4484 4485 4486 4487
	else {
		/* Unicast addresses changes may only happen under the rtnl,
		 * therefore calling __dev_set_promiscuity here is safe.
		 */
4488
		if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
4489 4490
			__dev_set_promiscuity(dev, 1);
			dev->uc_promisc = 1;
4491
		} else if (netdev_uc_empty(dev) && dev->uc_promisc) {
4492 4493 4494 4495
			__dev_set_promiscuity(dev, -1);
			dev->uc_promisc = 0;
		}

4496 4497
		if (ops->ndo_set_multicast_list)
			ops->ndo_set_multicast_list(dev);
4498 4499 4500 4501 4502
	}
}

void dev_set_rx_mode(struct net_device *dev)
{
4503
	netif_addr_lock_bh(dev);
4504
	__dev_set_rx_mode(dev);
4505
	netif_addr_unlock_bh(dev);
L
Linus Torvalds 已提交
4506 4507
}

4508 4509 4510 4511 4512 4513 4514 4515 4516 4517 4518 4519 4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531
/**
 *	dev_ethtool_get_settings - call device's ethtool_ops::get_settings()
 *	@dev: device
 *	@cmd: memory area for ethtool_ops::get_settings() result
 *
 *      The cmd arg is initialized properly (cleared and
 *      ethtool_cmd::cmd field set to ETHTOOL_GSET).
 *
 *	Return device's ethtool_ops::get_settings() result value or
 *	-EOPNOTSUPP when device doesn't expose
 *	ethtool_ops::get_settings() operation.
 */
int dev_ethtool_get_settings(struct net_device *dev,
			     struct ethtool_cmd *cmd)
{
	if (!dev->ethtool_ops || !dev->ethtool_ops->get_settings)
		return -EOPNOTSUPP;

	memset(cmd, 0, sizeof(struct ethtool_cmd));
	cmd->cmd = ETHTOOL_GSET;
	return dev->ethtool_ops->get_settings(dev, cmd);
}
EXPORT_SYMBOL(dev_ethtool_get_settings);

4532 4533 4534 4535 4536 4537
/**
 *	dev_get_flags - get flags reported to userspace
 *	@dev: device
 *
 *	Get the combination of flag bits exported through APIs to userspace.
 */
L
Linus Torvalds 已提交
4538 4539 4540 4541 4542 4543
unsigned dev_get_flags(const struct net_device *dev)
{
	unsigned flags;

	flags = (dev->flags & ~(IFF_PROMISC |
				IFF_ALLMULTI |
S
Stefan Rompf 已提交
4544 4545 4546
				IFF_RUNNING |
				IFF_LOWER_UP |
				IFF_DORMANT)) |
L
Linus Torvalds 已提交
4547 4548 4549
		(dev->gflags & (IFF_PROMISC |
				IFF_ALLMULTI));

S
Stefan Rompf 已提交
4550 4551 4552 4553 4554 4555 4556 4557
	if (netif_running(dev)) {
		if (netif_oper_up(dev))
			flags |= IFF_RUNNING;
		if (netif_carrier_ok(dev))
			flags |= IFF_LOWER_UP;
		if (netif_dormant(dev))
			flags |= IFF_DORMANT;
	}
L
Linus Torvalds 已提交
4558 4559 4560

	return flags;
}
E
Eric Dumazet 已提交
4561
EXPORT_SYMBOL(dev_get_flags);
L
Linus Torvalds 已提交
4562

4563
int __dev_change_flags(struct net_device *dev, unsigned int flags)
L
Linus Torvalds 已提交
4564 4565
{
	int old_flags = dev->flags;
4566
	int ret;
L
Linus Torvalds 已提交
4567

4568 4569
	ASSERT_RTNL();

L
Linus Torvalds 已提交
4570 4571 4572 4573 4574 4575 4576 4577 4578 4579 4580 4581 4582 4583
	/*
	 *	Set the flags on our device.
	 */

	dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
			       IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
			       IFF_AUTOMEDIA)) |
		     (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
				    IFF_ALLMULTI));

	/*
	 *	Load in the correct multicast list now the flags have changed.
	 */

4584 4585
	if ((old_flags ^ flags) & IFF_MULTICAST)
		dev_change_rx_flags(dev, IFF_MULTICAST);
4586

4587
	dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
4588 4589 4590 4591 4592 4593 4594 4595 4596

	/*
	 *	Have we downed the interface. We handle IFF_UP ourselves
	 *	according to user attempts to set it, rather than blindly
	 *	setting it.
	 */

	ret = 0;
	if ((old_flags ^ flags) & IFF_UP) {	/* Bit is different  ? */
4597
		ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
L
Linus Torvalds 已提交
4598 4599

		if (!ret)
4600
			dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
4601 4602 4603
	}

	if ((flags ^ dev->gflags) & IFF_PROMISC) {
E
Eric Dumazet 已提交
4604 4605
		int inc = (flags & IFF_PROMISC) ? 1 : -1;

L
Linus Torvalds 已提交
4606 4607 4608 4609 4610 4611 4612 4613 4614
		dev->gflags ^= IFF_PROMISC;
		dev_set_promiscuity(dev, inc);
	}

	/* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
	   is important. Some (broken) drivers set IFF_PROMISC, when
	   IFF_ALLMULTI is requested not asking us and not reporting.
	 */
	if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
E
Eric Dumazet 已提交
4615 4616
		int inc = (flags & IFF_ALLMULTI) ? 1 : -1;

L
Linus Torvalds 已提交
4617 4618 4619 4620
		dev->gflags ^= IFF_ALLMULTI;
		dev_set_allmulti(dev, inc);
	}

4621 4622 4623 4624 4625 4626 4627 4628 4629 4630 4631 4632 4633 4634 4635 4636 4637 4638 4639 4640 4641 4642 4643 4644 4645 4646 4647 4648 4649 4650 4651 4652 4653 4654 4655 4656 4657
	return ret;
}

void __dev_notify_flags(struct net_device *dev, unsigned int old_flags)
{
	unsigned int changes = dev->flags ^ old_flags;

	if (changes & IFF_UP) {
		if (dev->flags & IFF_UP)
			call_netdevice_notifiers(NETDEV_UP, dev);
		else
			call_netdevice_notifiers(NETDEV_DOWN, dev);
	}

	if (dev->flags & IFF_UP &&
	    (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE)))
		call_netdevice_notifiers(NETDEV_CHANGE, dev);
}

/**
 *	dev_change_flags - change device settings
 *	@dev: device
 *	@flags: device state flags
 *
 *	Change settings on device based state flags. The flags are
 *	in the userspace exported format.
 */
int dev_change_flags(struct net_device *dev, unsigned flags)
{
	int ret, changes;
	int old_flags = dev->flags;

	ret = __dev_change_flags(dev, flags);
	if (ret < 0)
		return ret;

	changes = old_flags ^ dev->flags;
4658 4659
	if (changes)
		rtmsg_ifinfo(RTM_NEWLINK, dev, changes);
L
Linus Torvalds 已提交
4660

4661
	__dev_notify_flags(dev, old_flags);
L
Linus Torvalds 已提交
4662 4663
	return ret;
}
E
Eric Dumazet 已提交
4664
EXPORT_SYMBOL(dev_change_flags);
L
Linus Torvalds 已提交
4665

4666 4667 4668 4669 4670 4671 4672
/**
 *	dev_set_mtu - Change maximum transfer unit
 *	@dev: device
 *	@new_mtu: new transfer unit
 *
 *	Change the maximum transfer size of the network device.
 */
L
Linus Torvalds 已提交
4673 4674
int dev_set_mtu(struct net_device *dev, int new_mtu)
{
4675
	const struct net_device_ops *ops = dev->netdev_ops;
L
Linus Torvalds 已提交
4676 4677 4678 4679 4680 4681 4682 4683 4684 4685 4686 4687 4688
	int err;

	if (new_mtu == dev->mtu)
		return 0;

	/*	MTU must be positive.	 */
	if (new_mtu < 0)
		return -EINVAL;

	if (!netif_device_present(dev))
		return -ENODEV;

	err = 0;
4689 4690
	if (ops->ndo_change_mtu)
		err = ops->ndo_change_mtu(dev, new_mtu);
L
Linus Torvalds 已提交
4691 4692
	else
		dev->mtu = new_mtu;
4693

L
Linus Torvalds 已提交
4694
	if (!err && dev->flags & IFF_UP)
4695
		call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
L
Linus Torvalds 已提交
4696 4697
	return err;
}
E
Eric Dumazet 已提交
4698
EXPORT_SYMBOL(dev_set_mtu);
L
Linus Torvalds 已提交
4699

4700 4701 4702 4703 4704 4705 4706 4707 4708 4709 4710
/**
 *	dev_set_group - Change group this device belongs to
 *	@dev: device
 *	@new_group: group this device should belong to
 */
void dev_set_group(struct net_device *dev, int new_group)
{
	dev->group = new_group;
}
EXPORT_SYMBOL(dev_set_group);

4711 4712 4713 4714 4715 4716 4717
/**
 *	dev_set_mac_address - Change Media Access Control Address
 *	@dev: device
 *	@sa: new address
 *
 *	Change the hardware (MAC) address of the device
 */
L
Linus Torvalds 已提交
4718 4719
int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
{
4720
	const struct net_device_ops *ops = dev->netdev_ops;
L
Linus Torvalds 已提交
4721 4722
	int err;

4723
	if (!ops->ndo_set_mac_address)
L
Linus Torvalds 已提交
4724 4725 4726 4727 4728
		return -EOPNOTSUPP;
	if (sa->sa_family != dev->type)
		return -EINVAL;
	if (!netif_device_present(dev))
		return -ENODEV;
4729
	err = ops->ndo_set_mac_address(dev, sa);
L
Linus Torvalds 已提交
4730
	if (!err)
4731
		call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
L
Linus Torvalds 已提交
4732 4733
	return err;
}
E
Eric Dumazet 已提交
4734
EXPORT_SYMBOL(dev_set_mac_address);
L
Linus Torvalds 已提交
4735 4736

/*
E
Eric Dumazet 已提交
4737
 *	Perform the SIOCxIFxxx calls, inside rcu_read_lock()
L
Linus Torvalds 已提交
4738
 */
4739
static int dev_ifsioc_locked(struct net *net, struct ifreq *ifr, unsigned int cmd)
L
Linus Torvalds 已提交
4740 4741
{
	int err;
E
Eric Dumazet 已提交
4742
	struct net_device *dev = dev_get_by_name_rcu(net, ifr->ifr_name);
L
Linus Torvalds 已提交
4743 4744 4745 4746 4747

	if (!dev)
		return -ENODEV;

	switch (cmd) {
E
Eric Dumazet 已提交
4748 4749 4750
	case SIOCGIFFLAGS:	/* Get interface flags */
		ifr->ifr_flags = (short) dev_get_flags(dev);
		return 0;
L
Linus Torvalds 已提交
4751

E
Eric Dumazet 已提交
4752 4753 4754 4755
	case SIOCGIFMETRIC:	/* Get the metric on the interface
				   (currently unused) */
		ifr->ifr_metric = 0;
		return 0;
L
Linus Torvalds 已提交
4756

E
Eric Dumazet 已提交
4757 4758 4759
	case SIOCGIFMTU:	/* Get the MTU of a device */
		ifr->ifr_mtu = dev->mtu;
		return 0;
L
Linus Torvalds 已提交
4760

E
Eric Dumazet 已提交
4761 4762 4763 4764 4765 4766 4767 4768
	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;
L
Linus Torvalds 已提交
4769

E
Eric Dumazet 已提交
4770 4771 4772
	case SIOCGIFSLAVE:
		err = -EINVAL;
		break;
4773

E
Eric Dumazet 已提交
4774 4775 4776 4777 4778 4779 4780 4781
	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;
4782

E
Eric Dumazet 已提交
4783 4784 4785
	case SIOCGIFINDEX:
		ifr->ifr_ifindex = dev->ifindex;
		return 0;
4786

E
Eric Dumazet 已提交
4787 4788 4789
	case SIOCGIFTXQLEN:
		ifr->ifr_qlen = dev->tx_queue_len;
		return 0;
4790

E
Eric Dumazet 已提交
4791 4792 4793 4794 4795
	default:
		/* dev_ioctl() should ensure this case
		 * is never reached
		 */
		WARN_ON(1);
4796
		err = -ENOTTY;
E
Eric Dumazet 已提交
4797
		break;
4798 4799 4800 4801 4802 4803 4804 4805 4806 4807 4808 4809

	}
	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);
J
Jarek Poplawski 已提交
4810
	const struct net_device_ops *ops;
4811 4812 4813 4814

	if (!dev)
		return -ENODEV;

J
Jarek Poplawski 已提交
4815 4816
	ops = dev->netdev_ops;

4817
	switch (cmd) {
E
Eric Dumazet 已提交
4818 4819
	case SIOCSIFFLAGS:	/* Set interface flags */
		return dev_change_flags(dev, ifr->ifr_flags);
4820

E
Eric Dumazet 已提交
4821 4822 4823
	case SIOCSIFMETRIC:	/* Set the metric on the interface
				   (currently unused) */
		return -EOPNOTSUPP;
4824

E
Eric Dumazet 已提交
4825 4826
	case SIOCSIFMTU:	/* Set the MTU of a device */
		return dev_set_mtu(dev, ifr->ifr_mtu);
L
Linus Torvalds 已提交
4827

E
Eric Dumazet 已提交
4828 4829
	case SIOCSIFHWADDR:
		return dev_set_mac_address(dev, &ifr->ifr_hwaddr);
L
Linus Torvalds 已提交
4830

E
Eric Dumazet 已提交
4831 4832 4833 4834 4835 4836 4837
	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;
L
Linus Torvalds 已提交
4838

E
Eric Dumazet 已提交
4839 4840
	case SIOCSIFMAP:
		if (ops->ndo_set_config) {
L
Linus Torvalds 已提交
4841 4842
			if (!netif_device_present(dev))
				return -ENODEV;
E
Eric Dumazet 已提交
4843 4844 4845
			return ops->ndo_set_config(dev, &ifr->ifr_map);
		}
		return -EOPNOTSUPP;
L
Linus Torvalds 已提交
4846

E
Eric Dumazet 已提交
4847 4848 4849 4850 4851 4852
	case SIOCADDMULTI:
		if ((!ops->ndo_set_multicast_list && !ops->ndo_set_rx_mode) ||
		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
			return -EINVAL;
		if (!netif_device_present(dev))
			return -ENODEV;
4853
		return dev_mc_add_global(dev, ifr->ifr_hwaddr.sa_data);
E
Eric Dumazet 已提交
4854 4855 4856 4857 4858 4859 4860

	case SIOCDELMULTI:
		if ((!ops->ndo_set_multicast_list && !ops->ndo_set_rx_mode) ||
		    ifr->ifr_hwaddr.sa_family != AF_UNSPEC)
			return -EINVAL;
		if (!netif_device_present(dev))
			return -ENODEV;
4861
		return dev_mc_del_global(dev, ifr->ifr_hwaddr.sa_data);
L
Linus Torvalds 已提交
4862

E
Eric Dumazet 已提交
4863 4864 4865 4866 4867
	case SIOCSIFTXQLEN:
		if (ifr->ifr_qlen < 0)
			return -EINVAL;
		dev->tx_queue_len = ifr->ifr_qlen;
		return 0;
L
Linus Torvalds 已提交
4868

E
Eric Dumazet 已提交
4869 4870 4871
	case SIOCSIFNAME:
		ifr->ifr_newname[IFNAMSIZ-1] = '\0';
		return dev_change_name(dev, ifr->ifr_newname);
L
Linus Torvalds 已提交
4872

E
Eric Dumazet 已提交
4873 4874 4875 4876 4877 4878 4879 4880 4881 4882 4883 4884 4885 4886 4887 4888 4889 4890 4891 4892 4893 4894 4895 4896 4897 4898 4899 4900
	/*
	 *	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;
L
Linus Torvalds 已提交
4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911 4912

	}
	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
4913
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
4914 4915 4916 4917 4918 4919 4920 4921 4922
 *	@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.
 */

4923
int dev_ioctl(struct net *net, unsigned int cmd, void __user *arg)
L
Linus Torvalds 已提交
4924 4925 4926 4927 4928 4929 4930 4931 4932 4933 4934
{
	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) {
4935
		rtnl_lock();
4936
		ret = dev_ifconf(net, (char __user *) arg);
4937
		rtnl_unlock();
L
Linus Torvalds 已提交
4938 4939 4940
		return ret;
	}
	if (cmd == SIOCGIFNAME)
4941
		return dev_ifname(net, (struct ifreq __user *)arg);
L
Linus Torvalds 已提交
4942 4943 4944 4945 4946 4947 4948 4949 4950 4951 4952 4953 4954 4955 4956

	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) {
E
Eric Dumazet 已提交
4957 4958 4959 4960 4961 4962 4963 4964 4965 4966 4967 4968 4969 4970 4971
	/*
	 *	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);
E
Eric Dumazet 已提交
4972
		rcu_read_lock();
E
Eric Dumazet 已提交
4973
		ret = dev_ifsioc_locked(net, &ifr, cmd);
E
Eric Dumazet 已提交
4974
		rcu_read_unlock();
E
Eric Dumazet 已提交
4975 4976 4977 4978 4979 4980 4981 4982
		if (!ret) {
			if (colon)
				*colon = ':';
			if (copy_to_user(arg, &ifr,
					 sizeof(struct ifreq)))
				ret = -EFAULT;
		}
		return ret;
L
Linus Torvalds 已提交
4983

E
Eric Dumazet 已提交
4984 4985 4986 4987 4988 4989 4990 4991 4992 4993 4994 4995 4996
	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;
L
Linus Torvalds 已提交
4997

E
Eric Dumazet 已提交
4998 4999 5000 5001 5002 5003 5004 5005 5006 5007 5008 5009 5010 5011 5012 5013 5014 5015 5016 5017 5018 5019 5020
	/*
	 *	These ioctl calls:
	 *	- require superuser power.
	 *	- require strict serialization.
	 *	- return a value
	 */
	case SIOCGMIIPHY:
	case SIOCGMIIREG:
	case SIOCSIFNAME:
		if (!capable(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;
L
Linus Torvalds 已提交
5021

E
Eric Dumazet 已提交
5022 5023 5024 5025 5026 5027 5028 5029 5030 5031 5032 5033 5034 5035 5036 5037 5038 5039 5040 5041 5042 5043 5044 5045 5046 5047 5048 5049 5050 5051 5052 5053 5054 5055 5056 5057 5058 5059 5060 5061 5062 5063
	/*
	 *	These ioctl calls:
	 *	- require superuser power.
	 *	- require strict serialization.
	 *	- do not return a value
	 */
	case SIOCSIFFLAGS:
	case SIOCSIFMETRIC:
	case SIOCSIFMTU:
	case SIOCSIFMAP:
	case SIOCSIFHWADDR:
	case SIOCSIFSLAVE:
	case SIOCADDMULTI:
	case SIOCDELMULTI:
	case SIOCSIFHWBROADCAST:
	case SIOCSIFTXQLEN:
	case SIOCSMIIREG:
	case SIOCBONDENSLAVE:
	case SIOCBONDRELEASE:
	case SIOCBONDSETHWADDR:
	case SIOCBONDCHANGEACTIVE:
	case SIOCBRADDIF:
	case SIOCBRDELIF:
	case SIOCSHWTSTAMP:
		if (!capable(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:
5064
		return -ENOTTY;
E
Eric Dumazet 已提交
5065 5066 5067 5068 5069 5070 5071 5072

	/*
	 *	Unknown or private ioctl.
	 */
	default:
		if (cmd == SIOCWANDEV ||
		    (cmd >= SIOCDEVPRIVATE &&
		     cmd <= SIOCDEVPRIVATE + 15)) {
5073
			dev_load(net, ifr.ifr_name);
L
Linus Torvalds 已提交
5074
			rtnl_lock();
5075
			ret = dev_ifsioc(net, &ifr, cmd);
L
Linus Torvalds 已提交
5076
			rtnl_unlock();
E
Eric Dumazet 已提交
5077 5078 5079
			if (!ret && copy_to_user(arg, &ifr,
						 sizeof(struct ifreq)))
				ret = -EFAULT;
L
Linus Torvalds 已提交
5080
			return ret;
E
Eric Dumazet 已提交
5081 5082 5083 5084
		}
		/* Take care of Wireless Extensions */
		if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST)
			return wext_handle_ioctl(net, &ifr, cmd, arg);
5085
		return -ENOTTY;
L
Linus Torvalds 已提交
5086 5087 5088 5089 5090 5091
	}
}


/**
 *	dev_new_index	-	allocate an ifindex
5092
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
5093 5094 5095 5096 5097
 *
 *	Returns a suitable unique value for a new device interface
 *	number.  The caller must hold the rtnl semaphore or the
 *	dev_base_lock to be sure it remains unique.
 */
5098
static int dev_new_index(struct net *net)
L
Linus Torvalds 已提交
5099 5100 5101 5102 5103
{
	static int ifindex;
	for (;;) {
		if (++ifindex <= 0)
			ifindex = 1;
5104
		if (!__dev_get_by_index(net, ifindex))
L
Linus Torvalds 已提交
5105 5106 5107 5108 5109
			return ifindex;
	}
}

/* Delayed registration/unregisteration */
5110
static LIST_HEAD(net_todo_list);
L
Linus Torvalds 已提交
5111

5112
static void net_set_todo(struct net_device *dev)
L
Linus Torvalds 已提交
5113 5114 5115 5116
{
	list_add_tail(&dev->todo_list, &net_todo_list);
}

5117
static void rollback_registered_many(struct list_head *head)
5118
{
5119
	struct net_device *dev, *tmp;
5120

5121 5122 5123
	BUG_ON(dev_boot_phase);
	ASSERT_RTNL();

5124
	list_for_each_entry_safe(dev, tmp, head, unreg_list) {
5125
		/* Some devices call without registering
5126 5127
		 * for initialization unwind. Remove those
		 * devices and proceed with the remaining.
5128 5129 5130 5131
		 */
		if (dev->reg_state == NETREG_UNINITIALIZED) {
			pr_debug("unregister_netdevice: device %s/%p never "
				 "was registered\n", dev->name, dev);
5132

5133
			WARN_ON(1);
5134 5135
			list_del(&dev->unreg_list);
			continue;
5136
		}
5137
		dev->dismantle = true;
5138
		BUG_ON(dev->reg_state != NETREG_REGISTERED);
5139
	}
5140

5141 5142
	/* If device is running, close it first. */
	dev_close_many(head);
5143

5144
	list_for_each_entry(dev, head, unreg_list) {
5145 5146
		/* And unlink it from device chain. */
		unlist_netdevice(dev);
5147

5148 5149
		dev->reg_state = NETREG_UNREGISTERING;
	}
5150 5151 5152

	synchronize_net();

5153 5154 5155
	list_for_each_entry(dev, head, unreg_list) {
		/* Shutdown queueing discipline. */
		dev_shutdown(dev);
5156 5157


5158 5159 5160 5161
		/* Notify protocols, that we are about to destroy
		   this device. They should clean all the things.
		*/
		call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5162

5163 5164 5165 5166
		if (!dev->rtnl_link_ops ||
		    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
			rtmsg_ifinfo(RTM_DELLINK, dev, ~0U);

5167 5168 5169
		/*
		 *	Flush the unicast and multicast chains
		 */
5170
		dev_uc_flush(dev);
5171
		dev_mc_flush(dev);
5172

5173 5174
		if (dev->netdev_ops->ndo_uninit)
			dev->netdev_ops->ndo_uninit(dev);
5175

5176 5177
		/* Notifier chain MUST detach us from master device. */
		WARN_ON(dev->master);
5178

5179 5180 5181
		/* Remove entries from kobject tree */
		netdev_unregister_kobject(dev);
	}
5182

5183
	/* Process any work delayed until the end of the batch */
5184
	dev = list_first_entry(head, struct net_device, unreg_list);
5185
	call_netdevice_notifiers(NETDEV_UNREGISTER_BATCH, dev);
5186

5187
	rcu_barrier();
5188

5189
	list_for_each_entry(dev, head, unreg_list)
5190 5191 5192 5193 5194 5195 5196 5197 5198
		dev_put(dev);
}

static void rollback_registered(struct net_device *dev)
{
	LIST_HEAD(single);

	list_add(&dev->unreg_list, &single);
	rollback_registered_many(&single);
E
Eric Dumazet 已提交
5199
	list_del(&single);
5200 5201
}

5202
u32 netdev_fix_features(struct net_device *dev, u32 features)
5203
{
5204 5205 5206
	/* Fix illegal checksum combinations */
	if ((features & NETIF_F_HW_CSUM) &&
	    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5207
		netdev_warn(dev, "mixed HW and IP checksum settings.\n");
5208 5209 5210 5211 5212
		features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
	}

	if ((features & NETIF_F_NO_CSUM) &&
	    (features & (NETIF_F_HW_CSUM|NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5213
		netdev_warn(dev, "mixed no checksumming and other settings.\n");
5214 5215 5216
		features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM|NETIF_F_HW_CSUM);
	}

5217 5218 5219
	/* Fix illegal SG+CSUM combinations. */
	if ((features & NETIF_F_SG) &&
	    !(features & NETIF_F_ALL_CSUM)) {
5220 5221
		netdev_dbg(dev,
			"Dropping NETIF_F_SG since no checksum feature.\n");
5222 5223 5224 5225
		features &= ~NETIF_F_SG;
	}

	/* TSO requires that SG is present as well. */
5226
	if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
5227
		netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
5228
		features &= ~NETIF_F_ALL_TSO;
5229 5230
	}

5231 5232 5233 5234
	/* TSO ECN requires that TSO is present as well. */
	if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
		features &= ~NETIF_F_TSO_ECN;

5235 5236
	/* Software GSO depends on SG. */
	if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
5237
		netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
5238 5239 5240
		features &= ~NETIF_F_GSO;
	}

5241
	/* UFO needs SG and checksumming */
5242
	if (features & NETIF_F_UFO) {
5243 5244 5245 5246
		/* maybe split UFO into V4 and V6? */
		if (!((features & NETIF_F_GEN_CSUM) ||
		    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
			    == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
5247
			netdev_dbg(dev,
5248
				"Dropping NETIF_F_UFO since no checksum offload features.\n");
5249 5250 5251 5252
			features &= ~NETIF_F_UFO;
		}

		if (!(features & NETIF_F_SG)) {
5253
			netdev_dbg(dev,
5254
				"Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
5255 5256 5257 5258 5259 5260 5261 5262
			features &= ~NETIF_F_UFO;
		}
	}

	return features;
}
EXPORT_SYMBOL(netdev_fix_features);

5263
int __netdev_update_features(struct net_device *dev)
5264 5265 5266 5267
{
	u32 features;
	int err = 0;

5268 5269
	ASSERT_RTNL();

5270 5271 5272 5273 5274 5275 5276 5277 5278
	features = netdev_get_wanted_features(dev);

	if (dev->netdev_ops->ndo_fix_features)
		features = dev->netdev_ops->ndo_fix_features(dev, features);

	/* driver might be less strict about feature dependencies */
	features = netdev_fix_features(dev, features);

	if (dev->features == features)
5279
		return 0;
5280

5281
	netdev_dbg(dev, "Features changed: 0x%08x -> 0x%08x\n",
5282 5283 5284 5285 5286
		dev->features, features);

	if (dev->netdev_ops->ndo_set_features)
		err = dev->netdev_ops->ndo_set_features(dev, features);

5287
	if (unlikely(err < 0)) {
5288 5289 5290
		netdev_err(dev,
			"set_features() failed (%d); wanted 0x%08x, left 0x%08x\n",
			err, features, dev->features);
5291 5292 5293 5294 5295 5296 5297 5298 5299
		return -1;
	}

	if (!err)
		dev->features = features;

	return 1;
}

5300 5301 5302 5303 5304 5305 5306 5307
/**
 *	netdev_update_features - recalculate device features
 *	@dev: the device to check
 *
 *	Recalculate dev->features set and send notifications if it
 *	has changed. Should be called after driver or hardware dependent
 *	conditions might have changed that influence the features.
 */
5308 5309 5310 5311
void netdev_update_features(struct net_device *dev)
{
	if (__netdev_update_features(dev))
		netdev_features_change(dev);
5312 5313 5314
}
EXPORT_SYMBOL(netdev_update_features);

5315 5316 5317 5318 5319 5320 5321 5322 5323 5324 5325 5326 5327 5328 5329 5330 5331
/**
 *	netdev_change_features - recalculate device features
 *	@dev: the device to check
 *
 *	Recalculate dev->features set and send notifications even
 *	if they have not changed. Should be called instead of
 *	netdev_update_features() if also dev->vlan_features might
 *	have changed to allow the changes to be propagated to stacked
 *	VLAN devices.
 */
void netdev_change_features(struct net_device *dev)
{
	__netdev_update_features(dev);
	netdev_features_change(dev);
}
EXPORT_SYMBOL(netdev_change_features);

5332 5333 5334 5335 5336 5337 5338 5339 5340 5341 5342 5343 5344 5345 5346 5347 5348 5349 5350 5351 5352 5353 5354 5355 5356 5357 5358
/**
 *	netif_stacked_transfer_operstate -	transfer operstate
 *	@rootdev: the root or lower level device to transfer state from
 *	@dev: the device to transfer operstate to
 *
 *	Transfer operational state from root to device. This is normally
 *	called when a stacking relationship exists between the root
 *	device and the device(a leaf device).
 */
void netif_stacked_transfer_operstate(const struct net_device *rootdev,
					struct net_device *dev)
{
	if (rootdev->operstate == IF_OPER_DORMANT)
		netif_dormant_on(dev);
	else
		netif_dormant_off(dev);

	if (netif_carrier_ok(rootdev)) {
		if (!netif_carrier_ok(dev))
			netif_carrier_on(dev);
	} else {
		if (netif_carrier_ok(dev))
			netif_carrier_off(dev);
	}
}
EXPORT_SYMBOL(netif_stacked_transfer_operstate);

T
Tom Herbert 已提交
5359
#ifdef CONFIG_RPS
5360 5361 5362
static int netif_alloc_rx_queues(struct net_device *dev)
{
	unsigned int i, count = dev->num_rx_queues;
T
Tom Herbert 已提交
5363
	struct netdev_rx_queue *rx;
5364

T
Tom Herbert 已提交
5365
	BUG_ON(count < 1);
5366

T
Tom Herbert 已提交
5367 5368 5369 5370
	rx = kcalloc(count, sizeof(struct netdev_rx_queue), GFP_KERNEL);
	if (!rx) {
		pr_err("netdev: Unable to allocate %u rx queues.\n", count);
		return -ENOMEM;
5371
	}
T
Tom Herbert 已提交
5372 5373 5374
	dev->_rx = rx;

	for (i = 0; i < count; i++)
T
Tom Herbert 已提交
5375
		rx[i].dev = dev;
5376 5377
	return 0;
}
T
Tom Herbert 已提交
5378
#endif
5379

C
Changli Gao 已提交
5380 5381 5382 5383 5384 5385 5386
static void netdev_init_one_queue(struct net_device *dev,
				  struct netdev_queue *queue, void *_unused)
{
	/* Initialize queue lock */
	spin_lock_init(&queue->_xmit_lock);
	netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
	queue->xmit_lock_owner = -1;
5387
	netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
C
Changli Gao 已提交
5388 5389 5390
	queue->dev = dev;
}

5391 5392 5393 5394 5395 5396 5397 5398 5399 5400 5401 5402 5403 5404
static int netif_alloc_netdev_queues(struct net_device *dev)
{
	unsigned int count = dev->num_tx_queues;
	struct netdev_queue *tx;

	BUG_ON(count < 1);

	tx = kcalloc(count, sizeof(struct netdev_queue), GFP_KERNEL);
	if (!tx) {
		pr_err("netdev: Unable to allocate %u tx queues.\n",
		       count);
		return -ENOMEM;
	}
	dev->_tx = tx;
T
Tom Herbert 已提交
5405

5406 5407
	netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
	spin_lock_init(&dev->tx_global_lock);
C
Changli Gao 已提交
5408 5409

	return 0;
5410 5411
}

L
Linus Torvalds 已提交
5412 5413 5414 5415 5416 5417 5418 5419 5420 5421 5422 5423 5424 5425 5426 5427 5428 5429 5430 5431
/**
 *	register_netdevice	- register a network device
 *	@dev: device to register
 *
 *	Take a completed network device structure and add it to the kernel
 *	interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
 *	chain. 0 is returned on success. A negative errno code is returned
 *	on a failure to set up the device, or if the name is a duplicate.
 *
 *	Callers must hold the rtnl semaphore. You may want
 *	register_netdev() instead of this.
 *
 *	BUGS:
 *	The locking appears insufficient to guarantee two parallel registers
 *	will not get the same name.
 */

int register_netdevice(struct net_device *dev)
{
	int ret;
5432
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
5433 5434 5435 5436

	BUG_ON(dev_boot_phase);
	ASSERT_RTNL();

5437 5438
	might_sleep();

L
Linus Torvalds 已提交
5439 5440
	/* When net_device's are persistent, this will be fatal. */
	BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
5441
	BUG_ON(!net);
L
Linus Torvalds 已提交
5442

5443
	spin_lock_init(&dev->addr_list_lock);
5444
	netdev_set_addr_lockdep_class(dev);
L
Linus Torvalds 已提交
5445 5446 5447

	dev->iflink = -1;

5448 5449 5450 5451
	ret = dev_get_valid_name(dev, dev->name);
	if (ret < 0)
		goto out;

L
Linus Torvalds 已提交
5452
	/* Init, if this function is available */
5453 5454
	if (dev->netdev_ops->ndo_init) {
		ret = dev->netdev_ops->ndo_init(dev);
L
Linus Torvalds 已提交
5455 5456 5457
		if (ret) {
			if (ret > 0)
				ret = -EIO;
5458
			goto out;
L
Linus Torvalds 已提交
5459 5460
		}
	}
5461

5462
	dev->ifindex = dev_new_index(net);
L
Linus Torvalds 已提交
5463 5464 5465
	if (dev->iflink == -1)
		dev->iflink = dev->ifindex;

5466 5467 5468 5469
	/* Transfer changeable features to wanted_features and enable
	 * software offloads (GSO and GRO).
	 */
	dev->hw_features |= NETIF_F_SOFT_FEATURES;
5470 5471
	dev->features |= NETIF_F_SOFT_FEATURES;
	dev->wanted_features = dev->features & dev->hw_features;
L
Linus Torvalds 已提交
5472

5473 5474 5475 5476 5477 5478 5479 5480
	/* Turn on no cache copy if HW is doing checksum */
	dev->hw_features |= NETIF_F_NOCACHE_COPY;
	if ((dev->features & NETIF_F_ALL_CSUM) &&
	    !(dev->features & NETIF_F_NO_CSUM)) {
		dev->wanted_features |= NETIF_F_NOCACHE_COPY;
		dev->features |= NETIF_F_NOCACHE_COPY;
	}

5481 5482 5483
	/* Enable GRO and NETIF_F_HIGHDMA for vlans by default,
	 * vlan_dev_init() will do the dev->features check, so these features
	 * are enabled only if supported by underlying device.
5484
	 */
5485
	dev->vlan_features |= (NETIF_F_GRO | NETIF_F_HIGHDMA);
5486

5487 5488 5489 5490 5491
	ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
	ret = notifier_to_errno(ret);
	if (ret)
		goto err_uninit;

5492
	ret = netdev_register_kobject(dev);
5493
	if (ret)
5494
		goto err_uninit;
5495 5496
	dev->reg_state = NETREG_REGISTERED;

5497
	__netdev_update_features(dev);
5498

L
Linus Torvalds 已提交
5499 5500 5501 5502 5503 5504 5505 5506 5507
	/*
	 *	Default initial state at registry is that the
	 *	device is present.
	 */

	set_bit(__LINK_STATE_PRESENT, &dev->state);

	dev_init_scheduler(dev);
	dev_hold(dev);
5508
	list_netdevice(dev);
L
Linus Torvalds 已提交
5509 5510

	/* Notify protocols, that a new device appeared. */
5511
	ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
5512
	ret = notifier_to_errno(ret);
5513 5514 5515 5516
	if (ret) {
		rollback_registered(dev);
		dev->reg_state = NETREG_UNREGISTERED;
	}
5517 5518 5519 5520
	/*
	 *	Prevent userspace races by waiting until the network
	 *	device is fully setup before sending notifications.
	 */
5521 5522 5523
	if (!dev->rtnl_link_ops ||
	    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);
L
Linus Torvalds 已提交
5524 5525 5526

out:
	return ret;
5527 5528

err_uninit:
5529 5530
	if (dev->netdev_ops->ndo_uninit)
		dev->netdev_ops->ndo_uninit(dev);
5531
	goto out;
L
Linus Torvalds 已提交
5532
}
E
Eric Dumazet 已提交
5533
EXPORT_SYMBOL(register_netdevice);
L
Linus Torvalds 已提交
5534

5535 5536 5537 5538 5539 5540 5541 5542 5543 5544 5545 5546 5547 5548 5549 5550 5551 5552 5553 5554 5555 5556 5557 5558 5559 5560 5561 5562 5563 5564 5565
/**
 *	init_dummy_netdev	- init a dummy network device for NAPI
 *	@dev: device to init
 *
 *	This takes a network device structure and initialize the minimum
 *	amount of fields so it can be used to schedule NAPI polls without
 *	registering a full blown interface. This is to be used by drivers
 *	that need to tie several hardware interfaces to a single NAPI
 *	poll scheduler due to HW limitations.
 */
int init_dummy_netdev(struct net_device *dev)
{
	/* Clear everything. Note we don't initialize spinlocks
	 * are they aren't supposed to be taken by any of the
	 * NAPI code and this dummy netdev is supposed to be
	 * only ever used for NAPI polls
	 */
	memset(dev, 0, sizeof(struct net_device));

	/* make sure we BUG if trying to hit standard
	 * register/unregister code path
	 */
	dev->reg_state = NETREG_DUMMY;

	/* NAPI wants this */
	INIT_LIST_HEAD(&dev->napi_list);

	/* a dummy interface is started by default */
	set_bit(__LINK_STATE_PRESENT, &dev->state);
	set_bit(__LINK_STATE_START, &dev->state);

E
Eric Dumazet 已提交
5566 5567 5568 5569 5570
	/* Note : We dont allocate pcpu_refcnt for dummy devices,
	 * because users of this 'device' dont need to change
	 * its refcount.
	 */

5571 5572 5573 5574 5575
	return 0;
}
EXPORT_SYMBOL_GPL(init_dummy_netdev);


L
Linus Torvalds 已提交
5576 5577 5578 5579 5580 5581 5582 5583 5584
/**
 *	register_netdev	- register a network device
 *	@dev: device to register
 *
 *	Take a completed network device structure and add it to the kernel
 *	interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
 *	chain. 0 is returned on success. A negative errno code is returned
 *	on a failure to set up the device, or if the name is a duplicate.
 *
5585
 *	This is a wrapper around register_netdevice that takes the rtnl semaphore
L
Linus Torvalds 已提交
5586 5587 5588 5589 5590 5591 5592 5593 5594 5595 5596 5597 5598 5599
 *	and expands the device name if you passed a format string to
 *	alloc_netdev.
 */
int register_netdev(struct net_device *dev)
{
	int err;

	rtnl_lock();
	err = register_netdevice(dev);
	rtnl_unlock();
	return err;
}
EXPORT_SYMBOL(register_netdev);

E
Eric Dumazet 已提交
5600 5601 5602 5603 5604 5605 5606 5607 5608 5609
int netdev_refcnt_read(const struct net_device *dev)
{
	int i, refcnt = 0;

	for_each_possible_cpu(i)
		refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
	return refcnt;
}
EXPORT_SYMBOL(netdev_refcnt_read);

L
Linus Torvalds 已提交
5610 5611 5612 5613 5614 5615 5616 5617 5618
/*
 * netdev_wait_allrefs - wait until all references are gone.
 *
 * This is called when unregistering network devices.
 *
 * Any protocol or device that holds a reference should register
 * for netdevice notification, and cleanup and put back the
 * reference if they receive an UNREGISTER event.
 * We can get stuck here if buggy protocols don't correctly
5619
 * call dev_put.
L
Linus Torvalds 已提交
5620 5621 5622 5623
 */
static void netdev_wait_allrefs(struct net_device *dev)
{
	unsigned long rebroadcast_time, warning_time;
E
Eric Dumazet 已提交
5624
	int refcnt;
L
Linus Torvalds 已提交
5625

5626 5627
	linkwatch_forget_dev(dev);

L
Linus Torvalds 已提交
5628
	rebroadcast_time = warning_time = jiffies;
E
Eric Dumazet 已提交
5629 5630 5631
	refcnt = netdev_refcnt_read(dev);

	while (refcnt != 0) {
L
Linus Torvalds 已提交
5632
		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
5633
			rtnl_lock();
L
Linus Torvalds 已提交
5634 5635

			/* Rebroadcast unregister notification */
5636
			call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
5637
			/* don't resend NETDEV_UNREGISTER_BATCH, _BATCH users
5638
			 * should have already handle it the first time */
L
Linus Torvalds 已提交
5639 5640 5641 5642 5643 5644 5645 5646 5647 5648 5649 5650

			if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
				     &dev->state)) {
				/* We must not have linkwatch events
				 * pending on unregister. If this
				 * happens, we simply run the queue
				 * unscheduled, resulting in a noop
				 * for this device.
				 */
				linkwatch_run_queue();
			}

5651
			__rtnl_unlock();
L
Linus Torvalds 已提交
5652 5653 5654 5655 5656 5657

			rebroadcast_time = jiffies;
		}

		msleep(250);

E
Eric Dumazet 已提交
5658 5659
		refcnt = netdev_refcnt_read(dev);

L
Linus Torvalds 已提交
5660 5661 5662 5663
		if (time_after(jiffies, warning_time + 10 * HZ)) {
			printk(KERN_EMERG "unregister_netdevice: "
			       "waiting for %s to become free. Usage "
			       "count = %d\n",
E
Eric Dumazet 已提交
5664
			       dev->name, refcnt);
L
Linus Torvalds 已提交
5665 5666 5667 5668 5669 5670 5671 5672 5673 5674 5675 5676 5677 5678 5679 5680 5681 5682 5683
			warning_time = jiffies;
		}
	}
}

/* The sequence is:
 *
 *	rtnl_lock();
 *	...
 *	register_netdevice(x1);
 *	register_netdevice(x2);
 *	...
 *	unregister_netdevice(y1);
 *	unregister_netdevice(y2);
 *      ...
 *	rtnl_unlock();
 *	free_netdev(y1);
 *	free_netdev(y2);
 *
H
Herbert Xu 已提交
5684
 * We are invoked by rtnl_unlock().
L
Linus Torvalds 已提交
5685
 * This allows us to deal with problems:
5686
 * 1) We can delete sysfs objects which invoke hotplug
L
Linus Torvalds 已提交
5687 5688 5689
 *    without deadlocking with linkwatch via keventd.
 * 2) Since we run with the RTNL semaphore not held, we can sleep
 *    safely in order to wait for the netdev refcnt to drop to zero.
H
Herbert Xu 已提交
5690 5691 5692
 *
 * We must not return until all unregister events added during
 * the interval the lock was held have been completed.
L
Linus Torvalds 已提交
5693 5694 5695
 */
void netdev_run_todo(void)
{
5696
	struct list_head list;
L
Linus Torvalds 已提交
5697 5698

	/* Snapshot list, allow later requests */
5699
	list_replace_init(&net_todo_list, &list);
H
Herbert Xu 已提交
5700 5701

	__rtnl_unlock();
5702

L
Linus Torvalds 已提交
5703 5704
	while (!list_empty(&list)) {
		struct net_device *dev
5705
			= list_first_entry(&list, struct net_device, todo_list);
L
Linus Torvalds 已提交
5706 5707
		list_del(&dev->todo_list);

5708 5709 5710 5711 5712 5713
		if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
			printk(KERN_ERR "network todo '%s' but state %d\n",
			       dev->name, dev->reg_state);
			dump_stack();
			continue;
		}
L
Linus Torvalds 已提交
5714

5715
		dev->reg_state = NETREG_UNREGISTERED;
L
Linus Torvalds 已提交
5716

5717
		on_each_cpu(flush_backlog, dev, 1);
5718

5719
		netdev_wait_allrefs(dev);
L
Linus Torvalds 已提交
5720

5721
		/* paranoia */
E
Eric Dumazet 已提交
5722
		BUG_ON(netdev_refcnt_read(dev));
E
Eric Dumazet 已提交
5723
		WARN_ON(rcu_dereference_raw(dev->ip_ptr));
E
Eric Dumazet 已提交
5724
		WARN_ON(rcu_dereference_raw(dev->ip6_ptr));
5725
		WARN_ON(dev->dn_ptr);
L
Linus Torvalds 已提交
5726

5727 5728
		if (dev->destructor)
			dev->destructor(dev);
5729 5730 5731

		/* Free network device */
		kobject_put(&dev->dev.kobj);
L
Linus Torvalds 已提交
5732 5733 5734
	}
}

5735 5736 5737 5738 5739 5740 5741 5742 5743 5744 5745 5746 5747 5748 5749 5750 5751 5752 5753 5754 5755
/* Convert net_device_stats to rtnl_link_stats64.  They have the same
 * fields in the same order, with only the type differing.
 */
static void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
				    const struct net_device_stats *netdev_stats)
{
#if BITS_PER_LONG == 64
        BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
        memcpy(stats64, netdev_stats, sizeof(*stats64));
#else
	size_t i, n = sizeof(*stats64) / sizeof(u64);
	const unsigned long *src = (const unsigned long *)netdev_stats;
	u64 *dst = (u64 *)stats64;

	BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
		     sizeof(*stats64) / sizeof(u64));
	for (i = 0; i < n; i++)
		dst[i] = src[i];
#endif
}

5756 5757 5758
/**
 *	dev_get_stats	- get network device statistics
 *	@dev: device to get statistics from
5759
 *	@storage: place to store stats
5760
 *
5761 5762 5763 5764
 *	Get network statistics from device. Return @storage.
 *	The device driver may provide its own method by setting
 *	dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
 *	otherwise the internal statistics structure is used.
5765
 */
5766 5767
struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
					struct rtnl_link_stats64 *storage)
5768
{
5769 5770
	const struct net_device_ops *ops = dev->netdev_ops;

5771 5772
	if (ops->ndo_get_stats64) {
		memset(storage, 0, sizeof(*storage));
5773 5774
		ops->ndo_get_stats64(dev, storage);
	} else if (ops->ndo_get_stats) {
5775
		netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
5776 5777
	} else {
		netdev_stats_to_stats64(storage, &dev->stats);
5778
	}
5779
	storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
5780
	return storage;
R
Rusty Russell 已提交
5781
}
5782
EXPORT_SYMBOL(dev_get_stats);
R
Rusty Russell 已提交
5783

5784
struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
5785
{
5786
	struct netdev_queue *queue = dev_ingress_queue(dev);
5787

5788 5789 5790 5791 5792 5793 5794 5795 5796 5797 5798 5799
#ifdef CONFIG_NET_CLS_ACT
	if (queue)
		return queue;
	queue = kzalloc(sizeof(*queue), GFP_KERNEL);
	if (!queue)
		return NULL;
	netdev_init_one_queue(dev, queue, NULL);
	queue->qdisc = &noop_qdisc;
	queue->qdisc_sleeping = &noop_qdisc;
	rcu_assign_pointer(dev->ingress_queue, queue);
#endif
	return queue;
5800 5801
}

L
Linus Torvalds 已提交
5802
/**
T
Tom Herbert 已提交
5803
 *	alloc_netdev_mqs - allocate network device
L
Linus Torvalds 已提交
5804 5805 5806
 *	@sizeof_priv:	size of private data to allocate space for
 *	@name:		device name format string
 *	@setup:		callback to initialize device
T
Tom Herbert 已提交
5807 5808
 *	@txqs:		the number of TX subqueues to allocate
 *	@rxqs:		the number of RX subqueues to allocate
L
Linus Torvalds 已提交
5809 5810
 *
 *	Allocates a struct net_device with private data area for driver use
5811
 *	and performs basic initialization.  Also allocates subquue structs
T
Tom Herbert 已提交
5812
 *	for each queue on the device.
L
Linus Torvalds 已提交
5813
 */
T
Tom Herbert 已提交
5814 5815 5816
struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
		void (*setup)(struct net_device *),
		unsigned int txqs, unsigned int rxqs)
L
Linus Torvalds 已提交
5817 5818
{
	struct net_device *dev;
5819
	size_t alloc_size;
5820
	struct net_device *p;
L
Linus Torvalds 已提交
5821

5822 5823
	BUG_ON(strlen(name) >= sizeof(dev->name));

T
Tom Herbert 已提交
5824
	if (txqs < 1) {
5825 5826 5827 5828 5829
		pr_err("alloc_netdev: Unable to allocate device "
		       "with zero queues.\n");
		return NULL;
	}

T
Tom Herbert 已提交
5830 5831 5832 5833 5834 5835 5836 5837
#ifdef CONFIG_RPS
	if (rxqs < 1) {
		pr_err("alloc_netdev: Unable to allocate device "
		       "with zero RX queues.\n");
		return NULL;
	}
#endif

5838
	alloc_size = sizeof(struct net_device);
5839 5840
	if (sizeof_priv) {
		/* ensure 32-byte alignment of private area */
5841
		alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
5842 5843 5844
		alloc_size += sizeof_priv;
	}
	/* ensure 32-byte alignment of whole construct */
5845
	alloc_size += NETDEV_ALIGN - 1;
L
Linus Torvalds 已提交
5846

5847
	p = kzalloc(alloc_size, GFP_KERNEL);
L
Linus Torvalds 已提交
5848
	if (!p) {
5849
		printk(KERN_ERR "alloc_netdev: Unable to allocate device.\n");
L
Linus Torvalds 已提交
5850 5851 5852
		return NULL;
	}

5853
	dev = PTR_ALIGN(p, NETDEV_ALIGN);
L
Linus Torvalds 已提交
5854
	dev->padded = (char *)dev - (char *)p;
5855

E
Eric Dumazet 已提交
5856 5857
	dev->pcpu_refcnt = alloc_percpu(int);
	if (!dev->pcpu_refcnt)
5858
		goto free_p;
5859 5860

	if (dev_addr_init(dev))
E
Eric Dumazet 已提交
5861
		goto free_pcpu;
5862

5863
	dev_mc_init(dev);
5864
	dev_uc_init(dev);
J
Jiri Pirko 已提交
5865

5866
	dev_net_set(dev, &init_net);
L
Linus Torvalds 已提交
5867

5868 5869 5870 5871 5872 5873 5874 5875
	dev->gso_max_size = GSO_MAX_SIZE;

	INIT_LIST_HEAD(&dev->napi_list);
	INIT_LIST_HEAD(&dev->unreg_list);
	INIT_LIST_HEAD(&dev->link_watch_list);
	dev->priv_flags = IFF_XMIT_DST_RELEASE;
	setup(dev);

T
Tom Herbert 已提交
5876 5877
	dev->num_tx_queues = txqs;
	dev->real_num_tx_queues = txqs;
5878
	if (netif_alloc_netdev_queues(dev))
5879
		goto free_all;
5880

E
Eric Dumazet 已提交
5881
#ifdef CONFIG_RPS
T
Tom Herbert 已提交
5882 5883
	dev->num_rx_queues = rxqs;
	dev->real_num_rx_queues = rxqs;
T
Tom Herbert 已提交
5884
	if (netif_alloc_rx_queues(dev))
5885
		goto free_all;
E
Eric Dumazet 已提交
5886
#endif
T
Tom Herbert 已提交
5887

L
Linus Torvalds 已提交
5888
	strcpy(dev->name, name);
5889
	dev->group = INIT_NETDEV_GROUP;
L
Linus Torvalds 已提交
5890
	return dev;
5891

5892 5893 5894 5895
free_all:
	free_netdev(dev);
	return NULL;

E
Eric Dumazet 已提交
5896 5897
free_pcpu:
	free_percpu(dev->pcpu_refcnt);
5898
	kfree(dev->_tx);
T
Tom Herbert 已提交
5899 5900 5901 5902
#ifdef CONFIG_RPS
	kfree(dev->_rx);
#endif

5903 5904 5905
free_p:
	kfree(p);
	return NULL;
L
Linus Torvalds 已提交
5906
}
T
Tom Herbert 已提交
5907
EXPORT_SYMBOL(alloc_netdev_mqs);
L
Linus Torvalds 已提交
5908 5909 5910 5911 5912

/**
 *	free_netdev - free network device
 *	@dev: device
 *
5913 5914
 *	This function does the last stage of destroying an allocated device
 * 	interface. The reference to the device object is released.
L
Linus Torvalds 已提交
5915 5916 5917 5918
 *	If this is the last reference then it will be freed.
 */
void free_netdev(struct net_device *dev)
{
5919 5920
	struct napi_struct *p, *n;

5921 5922
	release_net(dev_net(dev));

5923
	kfree(dev->_tx);
T
Tom Herbert 已提交
5924 5925 5926
#ifdef CONFIG_RPS
	kfree(dev->_rx);
#endif
5927

5928 5929
	kfree(rcu_dereference_raw(dev->ingress_queue));

5930 5931 5932
	/* Flush device addresses */
	dev_addr_flush(dev);

5933 5934 5935
	list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
		netif_napi_del(p);

E
Eric Dumazet 已提交
5936 5937 5938
	free_percpu(dev->pcpu_refcnt);
	dev->pcpu_refcnt = NULL;

S
Stephen Hemminger 已提交
5939
	/*  Compatibility with error handling in drivers */
L
Linus Torvalds 已提交
5940 5941 5942 5943 5944 5945 5946 5947
	if (dev->reg_state == NETREG_UNINITIALIZED) {
		kfree((char *)dev - dev->padded);
		return;
	}

	BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
	dev->reg_state = NETREG_RELEASED;

5948 5949
	/* will free via device release */
	put_device(&dev->dev);
L
Linus Torvalds 已提交
5950
}
E
Eric Dumazet 已提交
5951
EXPORT_SYMBOL(free_netdev);
5952

5953 5954 5955 5956 5957 5958
/**
 *	synchronize_net -  Synchronize with packet receive processing
 *
 *	Wait for packets currently being received to be done.
 *	Does not block later packets from starting.
 */
5959
void synchronize_net(void)
L
Linus Torvalds 已提交
5960 5961
{
	might_sleep();
5962 5963 5964 5965
	if (rtnl_is_locked())
		synchronize_rcu_expedited();
	else
		synchronize_rcu();
L
Linus Torvalds 已提交
5966
}
E
Eric Dumazet 已提交
5967
EXPORT_SYMBOL(synchronize_net);
L
Linus Torvalds 已提交
5968 5969

/**
5970
 *	unregister_netdevice_queue - remove device from the kernel
L
Linus Torvalds 已提交
5971
 *	@dev: device
5972
 *	@head: list
5973
 *
L
Linus Torvalds 已提交
5974
 *	This function shuts down a device interface and removes it
5975
 *	from the kernel tables.
5976
 *	If head not NULL, device is queued to be unregistered later.
L
Linus Torvalds 已提交
5977 5978 5979 5980 5981
 *
 *	Callers must hold the rtnl semaphore.  You may want
 *	unregister_netdev() instead of this.
 */

5982
void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
L
Linus Torvalds 已提交
5983
{
5984 5985
	ASSERT_RTNL();

5986
	if (head) {
5987
		list_move_tail(&dev->unreg_list, head);
5988 5989 5990 5991 5992
	} else {
		rollback_registered(dev);
		/* Finish processing unregister after unlock */
		net_set_todo(dev);
	}
L
Linus Torvalds 已提交
5993
}
5994
EXPORT_SYMBOL(unregister_netdevice_queue);
L
Linus Torvalds 已提交
5995

5996 5997 5998 5999 6000 6001 6002 6003 6004 6005 6006 6007 6008 6009
/**
 *	unregister_netdevice_many - unregister many devices
 *	@head: list of devices
 */
void unregister_netdevice_many(struct list_head *head)
{
	struct net_device *dev;

	if (!list_empty(head)) {
		rollback_registered_many(head);
		list_for_each_entry(dev, head, unreg_list)
			net_set_todo(dev);
	}
}
6010
EXPORT_SYMBOL(unregister_netdevice_many);
6011

L
Linus Torvalds 已提交
6012 6013 6014 6015 6016
/**
 *	unregister_netdev - remove device from the kernel
 *	@dev: device
 *
 *	This function shuts down a device interface and removes it
6017
 *	from the kernel tables.
L
Linus Torvalds 已提交
6018 6019 6020 6021 6022 6023 6024 6025 6026 6027 6028 6029 6030
 *
 *	This is just a wrapper for unregister_netdevice that takes
 *	the rtnl semaphore.  In general you want to use this and not
 *	unregister_netdevice.
 */
void unregister_netdev(struct net_device *dev)
{
	rtnl_lock();
	unregister_netdevice(dev);
	rtnl_unlock();
}
EXPORT_SYMBOL(unregister_netdev);

6031 6032 6033 6034 6035 6036 6037 6038 6039 6040 6041 6042 6043 6044 6045 6046 6047 6048 6049 6050 6051 6052 6053 6054 6055 6056 6057 6058 6059 6060 6061 6062
/**
 *	dev_change_net_namespace - move device to different nethost namespace
 *	@dev: device
 *	@net: network namespace
 *	@pat: If not NULL name pattern to try if the current device name
 *	      is already taken in the destination network namespace.
 *
 *	This function shuts down a device interface and moves it
 *	to a new network namespace. On success 0 is returned, on
 *	a failure a netagive errno code is returned.
 *
 *	Callers must hold the rtnl semaphore.
 */

int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
{
	int err;

	ASSERT_RTNL();

	/* Don't allow namespace local devices to be moved. */
	err = -EINVAL;
	if (dev->features & NETIF_F_NETNS_LOCAL)
		goto out;

	/* Ensure the device has been registrered */
	err = -EINVAL;
	if (dev->reg_state != NETREG_REGISTERED)
		goto out;

	/* Get out if there is nothing todo */
	err = 0;
6063
	if (net_eq(dev_net(dev), net))
6064 6065 6066 6067 6068 6069
		goto out;

	/* Pick the destination device name, and ensure
	 * we can use it in the destination network namespace.
	 */
	err = -EEXIST;
6070
	if (__dev_get_by_name(net, dev->name)) {
6071 6072 6073
		/* We get here if we can't use the current device name */
		if (!pat)
			goto out;
6074
		if (dev_get_valid_name(dev, pat) < 0)
6075 6076 6077 6078 6079 6080 6081 6082
			goto out;
	}

	/*
	 * And now a mini version of register_netdevice unregister_netdevice.
	 */

	/* If device is running close it first. */
6083
	dev_close(dev);
6084 6085 6086 6087 6088 6089 6090 6091 6092 6093 6094 6095

	/* And unlink it from device chain */
	err = -ENODEV;
	unlist_netdevice(dev);

	synchronize_net();

	/* Shutdown queueing discipline. */
	dev_shutdown(dev);

	/* Notify protocols, that we are about to destroy
	   this device. They should clean all the things.
6096 6097 6098 6099

	   Note that dev->reg_state stays at NETREG_REGISTERED.
	   This is wanted because this way 8021q and macvlan know
	   the device is just moving and can keep their slaves up.
6100 6101
	*/
	call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6102
	call_netdevice_notifiers(NETDEV_UNREGISTER_BATCH, dev);
6103 6104 6105 6106

	/*
	 *	Flush the unicast and multicast chains
	 */
6107
	dev_uc_flush(dev);
6108
	dev_mc_flush(dev);
6109 6110

	/* Actually switch the network namespace */
6111
	dev_net_set(dev, net);
6112 6113 6114 6115 6116 6117 6118 6119 6120

	/* If there is an ifindex conflict assign a new one */
	if (__dev_get_by_index(net, dev->ifindex)) {
		int iflink = (dev->iflink == dev->ifindex);
		dev->ifindex = dev_new_index(net);
		if (iflink)
			dev->iflink = dev->ifindex;
	}

6121
	/* Fixup kobjects */
6122
	err = device_rename(&dev->dev, dev->name);
6123
	WARN_ON(err);
6124 6125 6126 6127 6128 6129 6130

	/* Add the device back in the hashes */
	list_netdevice(dev);

	/* Notify protocols, that a new device appeared. */
	call_netdevice_notifiers(NETDEV_REGISTER, dev);

6131 6132 6133 6134 6135 6136
	/*
	 *	Prevent userspace races by waiting until the network
	 *	device is fully setup before sending notifications.
	 */
	rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U);

6137 6138 6139 6140 6141
	synchronize_net();
	err = 0;
out:
	return err;
}
6142
EXPORT_SYMBOL_GPL(dev_change_net_namespace);
6143

L
Linus Torvalds 已提交
6144 6145 6146 6147 6148 6149 6150 6151 6152
static int dev_cpu_callback(struct notifier_block *nfb,
			    unsigned long action,
			    void *ocpu)
{
	struct sk_buff **list_skb;
	struct sk_buff *skb;
	unsigned int cpu, oldcpu = (unsigned long)ocpu;
	struct softnet_data *sd, *oldsd;

6153
	if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
L
Linus Torvalds 已提交
6154 6155 6156 6157 6158 6159 6160 6161 6162 6163 6164 6165 6166 6167 6168 6169
		return NOTIFY_OK;

	local_irq_disable();
	cpu = smp_processor_id();
	sd = &per_cpu(softnet_data, cpu);
	oldsd = &per_cpu(softnet_data, oldcpu);

	/* Find end of our completion_queue. */
	list_skb = &sd->completion_queue;
	while (*list_skb)
		list_skb = &(*list_skb)->next;
	/* Append completion queue from offline CPU. */
	*list_skb = oldsd->completion_queue;
	oldsd->completion_queue = NULL;

	/* Append output queue from offline CPU. */
6170 6171 6172 6173 6174 6175
	if (oldsd->output_queue) {
		*sd->output_queue_tailp = oldsd->output_queue;
		sd->output_queue_tailp = oldsd->output_queue_tailp;
		oldsd->output_queue = NULL;
		oldsd->output_queue_tailp = &oldsd->output_queue;
	}
L
Linus Torvalds 已提交
6176 6177 6178 6179 6180

	raise_softirq_irqoff(NET_TX_SOFTIRQ);
	local_irq_enable();

	/* Process offline CPU's input_pkt_queue */
6181
	while ((skb = __skb_dequeue(&oldsd->process_queue))) {
L
Linus Torvalds 已提交
6182
		netif_rx(skb);
6183
		input_queue_head_incr(oldsd);
T
Tom Herbert 已提交
6184
	}
6185
	while ((skb = __skb_dequeue(&oldsd->input_pkt_queue))) {
6186
		netif_rx(skb);
6187 6188
		input_queue_head_incr(oldsd);
	}
L
Linus Torvalds 已提交
6189 6190 6191 6192 6193

	return NOTIFY_OK;
}


6194
/**
6195 6196 6197 6198
 *	netdev_increment_features - increment feature set by one
 *	@all: current feature set
 *	@one: new feature set
 *	@mask: mask feature set
6199 6200
 *
 *	Computes a new feature set after adding a device with feature set
6201 6202
 *	@one to the master device with current feature set @all.  Will not
 *	enable anything that is off in @mask. Returns the new feature set.
6203
 */
6204
u32 netdev_increment_features(u32 all, u32 one, u32 mask)
6205
{
6206 6207 6208
	if (mask & NETIF_F_GEN_CSUM)
		mask |= NETIF_F_ALL_CSUM;
	mask |= NETIF_F_VLAN_CHALLENGED;
6209

6210 6211
	all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
	all &= one | ~NETIF_F_ALL_FOR_ALL;
6212

6213 6214 6215
	/* If device needs checksumming, downgrade to it. */
	if (all & (NETIF_F_ALL_CSUM & ~NETIF_F_NO_CSUM))
		all &= ~NETIF_F_NO_CSUM;
6216

6217 6218 6219
	/* If one device supports hw checksumming, set for all. */
	if (all & NETIF_F_GEN_CSUM)
		all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
6220 6221 6222

	return all;
}
6223
EXPORT_SYMBOL(netdev_increment_features);
6224

6225 6226 6227 6228 6229 6230 6231 6232 6233 6234 6235 6236 6237
static struct hlist_head *netdev_create_hash(void)
{
	int i;
	struct hlist_head *hash;

	hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
	if (hash != NULL)
		for (i = 0; i < NETDEV_HASHENTRIES; i++)
			INIT_HLIST_HEAD(&hash[i]);

	return hash;
}

6238
/* Initialize per network namespace state */
6239
static int __net_init netdev_init(struct net *net)
6240 6241 6242
{
	INIT_LIST_HEAD(&net->dev_base_head);

6243 6244 6245
	net->dev_name_head = netdev_create_hash();
	if (net->dev_name_head == NULL)
		goto err_name;
6246

6247 6248 6249
	net->dev_index_head = netdev_create_hash();
	if (net->dev_index_head == NULL)
		goto err_idx;
6250 6251

	return 0;
6252 6253 6254 6255 6256

err_idx:
	kfree(net->dev_name_head);
err_name:
	return -ENOMEM;
6257 6258
}

6259 6260 6261 6262 6263 6264 6265 6266
/**
 *	netdev_drivername - network driver for the device
 *	@dev: network device
 *	@buffer: buffer for resulting name
 *	@len: size of buffer
 *
 *	Determine network driver for device.
 */
6267
char *netdev_drivername(const struct net_device *dev, char *buffer, int len)
6268
{
6269 6270
	const struct device_driver *driver;
	const struct device *parent;
6271 6272 6273 6274 6275 6276 6277 6278 6279 6280 6281 6282 6283 6284 6285 6286

	if (len <= 0 || !buffer)
		return buffer;
	buffer[0] = 0;

	parent = dev->dev.parent;

	if (!parent)
		return buffer;

	driver = parent->driver;
	if (driver && driver->name)
		strlcpy(buffer, driver->name, len);
	return buffer;
}

6287 6288 6289 6290 6291 6292 6293 6294 6295 6296 6297 6298 6299 6300 6301 6302 6303 6304 6305 6306 6307 6308 6309 6310 6311 6312 6313 6314 6315 6316 6317 6318 6319 6320 6321 6322 6323 6324 6325 6326 6327 6328 6329 6330 6331 6332 6333 6334 6335 6336 6337 6338 6339 6340 6341 6342 6343 6344 6345 6346 6347 6348
static int __netdev_printk(const char *level, const struct net_device *dev,
			   struct va_format *vaf)
{
	int r;

	if (dev && dev->dev.parent)
		r = dev_printk(level, dev->dev.parent, "%s: %pV",
			       netdev_name(dev), vaf);
	else if (dev)
		r = printk("%s%s: %pV", level, netdev_name(dev), vaf);
	else
		r = printk("%s(NULL net_device): %pV", level, vaf);

	return r;
}

int netdev_printk(const char *level, const struct net_device *dev,
		  const char *format, ...)
{
	struct va_format vaf;
	va_list args;
	int r;

	va_start(args, format);

	vaf.fmt = format;
	vaf.va = &args;

	r = __netdev_printk(level, dev, &vaf);
	va_end(args);

	return r;
}
EXPORT_SYMBOL(netdev_printk);

#define define_netdev_printk_level(func, level)			\
int func(const struct net_device *dev, const char *fmt, ...)	\
{								\
	int r;							\
	struct va_format vaf;					\
	va_list args;						\
								\
	va_start(args, fmt);					\
								\
	vaf.fmt = fmt;						\
	vaf.va = &args;						\
								\
	r = __netdev_printk(level, dev, &vaf);			\
	va_end(args);						\
								\
	return r;						\
}								\
EXPORT_SYMBOL(func);

define_netdev_printk_level(netdev_emerg, KERN_EMERG);
define_netdev_printk_level(netdev_alert, KERN_ALERT);
define_netdev_printk_level(netdev_crit, KERN_CRIT);
define_netdev_printk_level(netdev_err, KERN_ERR);
define_netdev_printk_level(netdev_warn, KERN_WARNING);
define_netdev_printk_level(netdev_notice, KERN_NOTICE);
define_netdev_printk_level(netdev_info, KERN_INFO);

6349
static void __net_exit netdev_exit(struct net *net)
6350 6351 6352 6353 6354
{
	kfree(net->dev_name_head);
	kfree(net->dev_index_head);
}

6355
static struct pernet_operations __net_initdata netdev_net_ops = {
6356 6357 6358 6359
	.init = netdev_init,
	.exit = netdev_exit,
};

6360
static void __net_exit default_device_exit(struct net *net)
6361
{
6362
	struct net_device *dev, *aux;
6363
	/*
6364
	 * Push all migratable network devices back to the
6365 6366 6367
	 * initial network namespace
	 */
	rtnl_lock();
6368
	for_each_netdev_safe(net, dev, aux) {
6369
		int err;
6370
		char fb_name[IFNAMSIZ];
6371 6372 6373 6374 6375

		/* Ignore unmoveable devices (i.e. loopback) */
		if (dev->features & NETIF_F_NETNS_LOCAL)
			continue;

6376 6377 6378
		/* Leave virtual devices for the generic cleanup */
		if (dev->rtnl_link_ops)
			continue;
6379

L
Lucas De Marchi 已提交
6380
		/* Push remaining network devices to init_net */
6381 6382
		snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
		err = dev_change_net_namespace(dev, &init_net, fb_name);
6383
		if (err) {
6384
			printk(KERN_EMERG "%s: failed to move %s to init_net: %d\n",
6385
				__func__, dev->name, err);
6386
			BUG();
6387 6388 6389 6390 6391
		}
	}
	rtnl_unlock();
}

6392 6393 6394
static void __net_exit default_device_exit_batch(struct list_head *net_list)
{
	/* At exit all network devices most be removed from a network
6395
	 * namespace.  Do this in the reverse order of registration.
6396 6397 6398 6399 6400 6401 6402 6403 6404 6405 6406 6407 6408 6409 6410 6411 6412
	 * Do this across as many network namespaces as possible to
	 * improve batching efficiency.
	 */
	struct net_device *dev;
	struct net *net;
	LIST_HEAD(dev_kill_list);

	rtnl_lock();
	list_for_each_entry(net, net_list, exit_list) {
		for_each_netdev_reverse(net, dev) {
			if (dev->rtnl_link_ops)
				dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
			else
				unregister_netdevice_queue(dev, &dev_kill_list);
		}
	}
	unregister_netdevice_many(&dev_kill_list);
E
Eric Dumazet 已提交
6413
	list_del(&dev_kill_list);
6414 6415 6416
	rtnl_unlock();
}

6417
static struct pernet_operations __net_initdata default_device_ops = {
6418
	.exit = default_device_exit,
6419
	.exit_batch = default_device_exit_batch,
6420 6421
};

L
Linus Torvalds 已提交
6422 6423 6424 6425 6426 6427 6428 6429 6430 6431 6432 6433 6434 6435 6436 6437 6438 6439 6440 6441
/*
 *	Initialize the DEV module. At boot time this walks the device list and
 *	unhooks any devices that fail to initialise (normally hardware not
 *	present) and leaves us with a valid list of present and active devices.
 *
 */

/*
 *       This is called single threaded during boot, so no need
 *       to take the rtnl semaphore.
 */
static int __init net_dev_init(void)
{
	int i, rc = -ENOMEM;

	BUG_ON(!dev_boot_phase);

	if (dev_proc_init())
		goto out;

6442
	if (netdev_kobject_init())
L
Linus Torvalds 已提交
6443 6444 6445
		goto out;

	INIT_LIST_HEAD(&ptype_all);
6446
	for (i = 0; i < PTYPE_HASH_SIZE; i++)
L
Linus Torvalds 已提交
6447 6448
		INIT_LIST_HEAD(&ptype_base[i]);

6449 6450
	if (register_pernet_subsys(&netdev_net_ops))
		goto out;
L
Linus Torvalds 已提交
6451 6452 6453 6454 6455

	/*
	 *	Initialise the packet receive queues.
	 */

6456
	for_each_possible_cpu(i) {
E
Eric Dumazet 已提交
6457
		struct softnet_data *sd = &per_cpu(softnet_data, i);
L
Linus Torvalds 已提交
6458

C
Changli Gao 已提交
6459
		memset(sd, 0, sizeof(*sd));
E
Eric Dumazet 已提交
6460
		skb_queue_head_init(&sd->input_pkt_queue);
6461
		skb_queue_head_init(&sd->process_queue);
E
Eric Dumazet 已提交
6462 6463
		sd->completion_queue = NULL;
		INIT_LIST_HEAD(&sd->poll_list);
6464 6465
		sd->output_queue = NULL;
		sd->output_queue_tailp = &sd->output_queue;
E
Eric Dumazet 已提交
6466
#ifdef CONFIG_RPS
E
Eric Dumazet 已提交
6467 6468 6469 6470
		sd->csd.func = rps_trigger_softirq;
		sd->csd.info = sd;
		sd->csd.flags = 0;
		sd->cpu = i;
6471
#endif
T
Tom Herbert 已提交
6472

E
Eric Dumazet 已提交
6473 6474 6475 6476
		sd->backlog.poll = process_backlog;
		sd->backlog.weight = weight_p;
		sd->backlog.gro_list = NULL;
		sd->backlog.gro_count = 0;
L
Linus Torvalds 已提交
6477 6478 6479 6480
	}

	dev_boot_phase = 0;

6481 6482 6483 6484 6485 6486 6487 6488 6489 6490 6491 6492 6493 6494 6495
	/* The loopback device is special if any other network devices
	 * is present in a network namespace the loopback device must
	 * be present. Since we now dynamically allocate and free the
	 * loopback device ensure this invariant is maintained by
	 * keeping the loopback device as the first device on the
	 * list of network devices.  Ensuring the loopback devices
	 * is the first device that appears and the last network device
	 * that disappears.
	 */
	if (register_pernet_device(&loopback_net_ops))
		goto out;

	if (register_pernet_device(&default_device_ops))
		goto out;

6496 6497
	open_softirq(NET_TX_SOFTIRQ, net_tx_action);
	open_softirq(NET_RX_SOFTIRQ, net_rx_action);
L
Linus Torvalds 已提交
6498 6499 6500 6501 6502 6503 6504 6505 6506 6507 6508

	hotcpu_notifier(dev_cpu_callback, 0);
	dst_init();
	dev_mcast_init();
	rc = 0;
out:
	return rc;
}

subsys_initcall(net_dev_init);

6509 6510
static int __init initialize_hashrnd(void)
{
T
Tom Herbert 已提交
6511
	get_random_bytes(&hashrnd, sizeof(hashrnd));
6512 6513 6514 6515 6516
	return 0;
}

late_initcall_sync(initialize_hashrnd);