dev.c 185.9 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 <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/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/module.h>
#include <linux/netpoll.h>
#include <linux/rcupdate.h>
#include <linux/delay.h>
#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 <net/mpls.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 <linux/static_key.h>
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#include <linux/hashtable.h>
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#include <linux/vmalloc.h>
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#include <linux/if_macvlan.h>
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#include <linux/errqueue.h>
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#include <linux/hrtimer.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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static DEFINE_SPINLOCK(ptype_lock);
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static DEFINE_SPINLOCK(offload_lock);
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struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
struct list_head ptype_all __read_mostly;	/* Taps */
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static struct list_head offload_base __read_mostly;
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static int netif_rx_internal(struct sk_buff *skb);
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static int call_netdevice_notifiers_info(unsigned long val,
					 struct net_device *dev,
					 struct netdev_notifier_info *info);
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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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/* protects napi_hash addition/deletion and napi_gen_id */
static DEFINE_SPINLOCK(napi_hash_lock);

static unsigned int napi_gen_id;
static DEFINE_HASHTABLE(napi_hash, 8);

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static seqcount_t devnet_rename_seq;
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static inline void dev_base_seq_inc(struct net *net)
{
	while (++net->dev_base_seq == 0);
}

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static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
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{
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	unsigned int 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 */
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static void list_netdevice(struct net_device *dev)
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{
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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);
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	dev_base_seq_inc(net);
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}

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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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	dev_base_seq_inc(dev_net(dev));
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}

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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,
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	 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
	 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
	 ARPHRD_IEEE802154, 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",
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	 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
	 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
	 "_xmit_IEEE802154", "_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))
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		return pt->dev ? &pt->dev->ptype_all : &ptype_all;
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	else
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		return pt->dev ? &pt->dev->ptype_specific :
				 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
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}

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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;
		}
	}

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	pr_warn("dev_remove_pack: %p not found\n", pt);
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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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/**
 *	dev_add_offload - register offload handlers
 *	@po: protocol offload declaration
 *
 *	Add protocol offload handlers to the networking stack. The passed
 *	&proto_offload is linked into kernel lists and may not be freed until
 *	it has been removed from the kernel lists.
 *
 *	This call does not sleep therefore it can not
 *	guarantee all CPU's that are in middle of receiving packets
 *	will see the new offload handlers (until the next received packet).
 */
void dev_add_offload(struct packet_offload *po)
{
	struct list_head *head = &offload_base;

	spin_lock(&offload_lock);
	list_add_rcu(&po->list, head);
	spin_unlock(&offload_lock);
}
EXPORT_SYMBOL(dev_add_offload);

/**
 *	__dev_remove_offload	 - remove offload handler
 *	@po: packet offload declaration
 *
 *	Remove a protocol offload handler that was previously added to the
 *	kernel offload handlers by dev_add_offload(). The passed &offload_type
 *	is removed from the kernel lists and can be freed or reused once this
 *	function returns.
 *
 *      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.
 */
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static void __dev_remove_offload(struct packet_offload *po)
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{
	struct list_head *head = &offload_base;
	struct packet_offload *po1;

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	spin_lock(&offload_lock);
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	list_for_each_entry(po1, head, list) {
		if (po == po1) {
			list_del_rcu(&po->list);
			goto out;
		}
	}

	pr_warn("dev_remove_offload: %p not found\n", po);
out:
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	spin_unlock(&offload_lock);
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}

/**
 *	dev_remove_offload	 - remove packet offload handler
 *	@po: packet offload declaration
 *
 *	Remove a packet offload handler that was previously added to the kernel
 *	offload handlers by dev_add_offload(). The passed &offload_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_offload(struct packet_offload *po)
{
	__dev_remove_offload(po);

	synchronize_net();
}
EXPORT_SYMBOL(dev_remove_offload);

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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));
558
			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] != ' ' &&
583
		    !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
	 */
618
	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
664
 *	@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.
 */

674
struct net_device *__dev_get_by_name(struct net *net, const char *name)
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{
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	struct net_device *dev;
	struct hlist_head *head = dev_name_hash(net, name);
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679
	hlist_for_each_entry(dev, head, name_hlist)
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		if (!strncmp(dev->name, name, IFNAMSIZ))
			return dev;
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	return NULL;
}
E
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EXPORT_SYMBOL(__dev_get_by_name);
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687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703
/**
 *	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 net_device *dev;
	struct hlist_head *head = dev_name_hash(net, name);

704
	hlist_for_each_entry_rcu(dev, head, name_hlist)
705 706 707 708 709 710 711
		if (!strncmp(dev->name, name, IFNAMSIZ))
			return dev;

	return NULL;
}
EXPORT_SYMBOL(dev_get_by_name_rcu);

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/**
 *	dev_get_by_name		- find a device by its name
714
 *	@net: the applicable net namespace
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 *	@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.
 */

724
struct net_device *dev_get_by_name(struct net *net, const char *name)
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{
	struct net_device *dev;

728 729
	rcu_read_lock();
	dev = dev_get_by_name_rcu(net, name);
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	if (dev)
		dev_hold(dev);
732
	rcu_read_unlock();
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	return dev;
}
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EXPORT_SYMBOL(dev_get_by_name);
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/**
 *	__dev_get_by_index - find a device by its ifindex
739
 *	@net: the applicable net namespace
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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.
 */

749
struct net_device *__dev_get_by_index(struct net *net, int ifindex)
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{
E
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	struct net_device *dev;
	struct hlist_head *head = dev_index_hash(net, ifindex);
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753

754
	hlist_for_each_entry(dev, head, index_hlist)
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		if (dev->ifindex == ifindex)
			return dev;
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	return NULL;
}
E
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EXPORT_SYMBOL(__dev_get_by_index);
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762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777
/**
 *	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 net_device *dev;
	struct hlist_head *head = dev_index_hash(net, ifindex);

778
	hlist_for_each_entry_rcu(dev, head, index_hlist)
779 780 781 782 783 784 785
		if (dev->ifindex == ifindex)
			return dev;

	return NULL;
}
EXPORT_SYMBOL(dev_get_by_index_rcu);

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/**
 *	dev_get_by_index - find a device by its ifindex
789
 *	@net: the applicable net namespace
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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 returned has
 *	had a reference added and the pointer is safe until the user calls
 *	dev_put to indicate they have finished with it.
 */

798
struct net_device *dev_get_by_index(struct net *net, int ifindex)
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{
	struct net_device *dev;

802 803
	rcu_read_lock();
	dev = dev_get_by_index_rcu(net, ifindex);
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	if (dev)
		dev_hold(dev);
806
	rcu_read_unlock();
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	return dev;
}
E
Eric Dumazet 已提交
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EXPORT_SYMBOL(dev_get_by_index);
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811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844
/**
 *	netdev_get_name - get a netdevice name, knowing its ifindex.
 *	@net: network namespace
 *	@name: a pointer to the buffer where the name will be stored.
 *	@ifindex: the ifindex of the interface to get the name from.
 *
 *	The use of raw_seqcount_begin() and cond_resched() before
 *	retrying is required as we want to give the writers a chance
 *	to complete when CONFIG_PREEMPT is not set.
 */
int netdev_get_name(struct net *net, char *name, int ifindex)
{
	struct net_device *dev;
	unsigned int seq;

retry:
	seq = raw_seqcount_begin(&devnet_rename_seq);
	rcu_read_lock();
	dev = dev_get_by_index_rcu(net, ifindex);
	if (!dev) {
		rcu_read_unlock();
		return -ENODEV;
	}

	strcpy(name, dev->name);
	rcu_read_unlock();
	if (read_seqcount_retry(&devnet_rename_seq, seq)) {
		cond_resched();
		goto retry;
	}

	return 0;
}

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/**
846
 *	dev_getbyhwaddr_rcu - find a device by its hardware address
847
 *	@net: the applicable net namespace
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 *	@type: media type of device
 *	@ha: hardware address
 *
 *	Search for an interface by MAC address. Returns NULL if the device
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 *	is not found or a pointer to the device.
 *	The caller must hold RCU or RTNL.
854
 *	The returned device has not had its ref count increased
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 *	and the caller must therefore be careful about locking
 *
 */

859 860
struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
				       const char *ha)
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{
	struct net_device *dev;

864
	for_each_netdev_rcu(net, dev)
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		if (dev->type == type &&
		    !memcmp(dev->dev_addr, ha, dev->addr_len))
867 868 869
			return dev;

	return NULL;
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}
871
EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
872

873
struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
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{
	struct net_device *dev;

877
	ASSERT_RTNL();
878
	for_each_netdev(net, dev)
879
		if (dev->type == type)
880 881 882
			return dev;

	return NULL;
883 884 885
}
EXPORT_SYMBOL(__dev_getfirstbyhwtype);

886
struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
887
{
888
	struct net_device *dev, *ret = NULL;
889

890 891 892 893 894 895 896 897 898
	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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}
EXPORT_SYMBOL(dev_getfirstbyhwtype);

/**
903
 *	__dev_get_by_flags - find any device with given flags
904
 *	@net: the applicable net namespace
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 *	@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
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Eric Dumazet 已提交
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 *	is not found or a pointer to the device. Must be called inside
910
 *	rtnl_lock(), and result refcount is unchanged.
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 */

913 914
struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags,
				      unsigned short mask)
L
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{
916
	struct net_device *dev, *ret;
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918 919
	ASSERT_RTNL();

920
	ret = NULL;
921
	for_each_netdev(net, dev) {
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		if (((dev->flags ^ if_flags) & mask) == 0) {
923
			ret = dev;
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			break;
		}
	}
927
	return ret;
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}
929
EXPORT_SYMBOL(__dev_get_by_flags);
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/**
 *	dev_valid_name - check if name is okay for network device
 *	@name: name string
 *
 *	Network device names need to be valid file names to
936 937
 *	to allow sysfs to work.  We also disallow any kind of
 *	whitespace.
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 */
939
bool dev_valid_name(const char *name)
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{
941
	if (*name == '\0')
942
		return false;
943
	if (strlen(name) >= IFNAMSIZ)
944
		return false;
945
	if (!strcmp(name, ".") || !strcmp(name, ".."))
946
		return false;
947 948

	while (*name) {
949
		if (*name == '/' || *name == ':' || isspace(*name))
950
			return false;
951 952
		name++;
	}
953
	return true;
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}
E
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EXPORT_SYMBOL(dev_valid_name);
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/**
958 959
 *	__dev_alloc_name - allocate a name for a device
 *	@net: network namespace to allocate the device name in
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 *	@name: name format string
961
 *	@buf:  scratch buffer and result name string
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 *
 *	Passed a format string - eg "lt%d" it will try and find a suitable
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 *	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.
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 */

972
static int __dev_alloc_name(struct net *net, const char *name, char *buf)
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{
	int i = 0;
	const char *p;
	const int max_netdevices = 8*PAGE_SIZE;
S
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	unsigned long *inuse;
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	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
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		inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
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		if (!inuse)
			return -ENOMEM;

995
		for_each_netdev(net, d) {
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			if (!sscanf(d->name, name, &i))
				continue;
			if (i < 0 || i >= max_netdevices)
				continue;

			/*  avoid cases where sscanf is not exact inverse of printf */
1002
			snprintf(buf, IFNAMSIZ, name, i);
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			if (!strncmp(buf, d->name, IFNAMSIZ))
				set_bit(i, inuse);
		}

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

1011 1012
	if (buf != name)
		snprintf(buf, IFNAMSIZ, name, i);
1013
	if (!__dev_get_by_name(net, buf))
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		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;
}

1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042
/**
 *	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;

1043 1044
	BUG_ON(!dev_net(dev));
	net = dev_net(dev);
1045 1046 1047 1048 1049
	ret = __dev_alloc_name(net, name, buf);
	if (ret >= 0)
		strlcpy(dev->name, buf, IFNAMSIZ);
	return ret;
}
E
Eric Dumazet 已提交
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EXPORT_SYMBOL(dev_alloc_name);
1051

1052 1053 1054
static int dev_alloc_name_ns(struct net *net,
			     struct net_device *dev,
			     const char *name)
1055
{
1056 1057
	char buf[IFNAMSIZ];
	int ret;
1058

1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069
	ret = __dev_alloc_name(net, name, buf);
	if (ret >= 0)
		strlcpy(dev->name, buf, IFNAMSIZ);
	return ret;
}

static int dev_get_valid_name(struct net *net,
			      struct net_device *dev,
			      const char *name)
{
	BUG_ON(!net);
1070

1071 1072 1073
	if (!dev_valid_name(name))
		return -EINVAL;

1074
	if (strchr(name, '%'))
1075
		return dev_alloc_name_ns(net, dev, name);
1076 1077
	else if (__dev_get_by_name(net, name))
		return -EEXIST;
1078 1079
	else if (dev->name != name)
		strlcpy(dev->name, name, IFNAMSIZ);
1080 1081 1082

	return 0;
}
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/**
 *	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.
 */
1092
int dev_change_name(struct net_device *dev, const char *newname)
L
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{
1094
	unsigned char old_assign_type;
1095
	char oldname[IFNAMSIZ];
L
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1096
	int err = 0;
1097
	int ret;
1098
	struct net *net;
L
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	ASSERT_RTNL();
1101
	BUG_ON(!dev_net(dev));
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1102

1103
	net = dev_net(dev);
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	if (dev->flags & IFF_UP)
		return -EBUSY;

1107
	write_seqcount_begin(&devnet_rename_seq);
1108 1109

	if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
1110
		write_seqcount_end(&devnet_rename_seq);
1111
		return 0;
1112
	}
1113

1114 1115
	memcpy(oldname, dev->name, IFNAMSIZ);

1116
	err = dev_get_valid_name(net, dev, newname);
1117
	if (err < 0) {
1118
		write_seqcount_end(&devnet_rename_seq);
1119
		return err;
1120
	}
L
Linus Torvalds 已提交
1121

1122 1123 1124
	if (oldname[0] && !strchr(oldname, '%'))
		netdev_info(dev, "renamed from %s\n", oldname);

1125 1126 1127
	old_assign_type = dev->name_assign_type;
	dev->name_assign_type = NET_NAME_RENAMED;

1128
rollback:
1129 1130 1131
	ret = device_rename(&dev->dev, dev->name);
	if (ret) {
		memcpy(dev->name, oldname, IFNAMSIZ);
1132
		dev->name_assign_type = old_assign_type;
1133
		write_seqcount_end(&devnet_rename_seq);
1134
		return ret;
1135
	}
1136

1137
	write_seqcount_end(&devnet_rename_seq);
1138

1139 1140
	netdev_adjacent_rename_links(dev, oldname);

1141
	write_lock_bh(&dev_base_lock);
1142
	hlist_del_rcu(&dev->name_hlist);
1143 1144 1145 1146 1147 1148
	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));
1149 1150
	write_unlock_bh(&dev_base_lock);

1151
	ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1152 1153 1154
	ret = notifier_to_errno(ret);

	if (ret) {
1155 1156
		/* err >= 0 after dev_alloc_name() or stores the first errno */
		if (err >= 0) {
1157
			err = ret;
1158
			write_seqcount_begin(&devnet_rename_seq);
1159
			memcpy(dev->name, oldname, IFNAMSIZ);
1160
			memcpy(oldname, newname, IFNAMSIZ);
1161 1162
			dev->name_assign_type = old_assign_type;
			old_assign_type = NET_NAME_RENAMED;
1163
			goto rollback;
1164
		} else {
1165
			pr_err("%s: name change rollback failed: %d\n",
1166
			       dev->name, ret);
1167 1168
		}
	}
L
Linus Torvalds 已提交
1169 1170 1171 1172

	return err;
}

1173 1174 1175 1176
/**
 *	dev_set_alias - change ifalias of a device
 *	@dev: device
 *	@alias: name up to IFALIASZ
1177
 *	@len: limit of bytes to copy from info
1178 1179 1180 1181 1182
 *
 *	Set ifalias for a device,
 */
int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
{
1183 1184
	char *new_ifalias;

1185 1186 1187 1188 1189
	ASSERT_RTNL();

	if (len >= IFALIASZ)
		return -EINVAL;

1190
	if (!len) {
1191 1192
		kfree(dev->ifalias);
		dev->ifalias = NULL;
1193 1194 1195
		return 0;
	}

1196 1197
	new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
	if (!new_ifalias)
1198
		return -ENOMEM;
1199
	dev->ifalias = new_ifalias;
1200 1201 1202 1203 1204 1205

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


1206
/**
S
Stephen Hemminger 已提交
1207
 *	netdev_features_change - device changes features
1208 1209 1210 1211 1212 1213
 *	@dev: device to cause notification
 *
 *	Called to indicate a device has changed features.
 */
void netdev_features_change(struct net_device *dev)
{
1214
	call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1215 1216 1217
}
EXPORT_SYMBOL(netdev_features_change);

L
Linus Torvalds 已提交
1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228
/**
 *	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) {
1229 1230 1231 1232 1233
		struct netdev_notifier_change_info change_info;

		change_info.flags_changed = 0;
		call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
					      &change_info.info);
1234
		rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL);
L
Linus Torvalds 已提交
1235 1236
	}
}
E
Eric Dumazet 已提交
1237
EXPORT_SYMBOL(netdev_state_change);
L
Linus Torvalds 已提交
1238

1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249
/**
 * 	netdev_notify_peers - notify network peers about existence of @dev
 * 	@dev: network device
 *
 * Generate traffic such that interested network peers are aware of
 * @dev, such as by generating a gratuitous ARP. This may be used when
 * a device wants to inform the rest of the network about some sort of
 * reconfiguration such as a failover event or virtual machine
 * migration.
 */
void netdev_notify_peers(struct net_device *dev)
1250
{
1251 1252 1253
	rtnl_lock();
	call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
	rtnl_unlock();
1254
}
1255
EXPORT_SYMBOL(netdev_notify_peers);
1256

1257
static int __dev_open(struct net_device *dev)
L
Linus Torvalds 已提交
1258
{
1259
	const struct net_device_ops *ops = dev->netdev_ops;
1260
	int ret;
L
Linus Torvalds 已提交
1261

1262 1263
	ASSERT_RTNL();

L
Linus Torvalds 已提交
1264 1265 1266
	if (!netif_device_present(dev))
		return -ENODEV;

1267 1268 1269 1270
	/* Block netpoll from trying to do any rx path servicing.
	 * If we don't do this there is a chance ndo_poll_controller
	 * or ndo_poll may be running while we open the device
	 */
1271
	netpoll_poll_disable(dev);
1272

1273 1274 1275 1276 1277
	ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
	ret = notifier_to_errno(ret);
	if (ret)
		return ret;

L
Linus Torvalds 已提交
1278
	set_bit(__LINK_STATE_START, &dev->state);
1279

1280 1281
	if (ops->ndo_validate_addr)
		ret = ops->ndo_validate_addr(dev);
1282

1283 1284
	if (!ret && ops->ndo_open)
		ret = ops->ndo_open(dev);
L
Linus Torvalds 已提交
1285

1286
	netpoll_poll_enable(dev);
1287

1288 1289 1290
	if (ret)
		clear_bit(__LINK_STATE_START, &dev->state);
	else {
L
Linus Torvalds 已提交
1291
		dev->flags |= IFF_UP;
1292
		dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
1293
		dev_activate(dev);
1294
		add_device_randomness(dev->dev_addr, dev->addr_len);
L
Linus Torvalds 已提交
1295
	}
1296

L
Linus Torvalds 已提交
1297 1298 1299 1300
	return ret;
}

/**
1301 1302
 *	dev_open	- prepare an interface for use.
 *	@dev:	device to open
L
Linus Torvalds 已提交
1303
 *
1304 1305 1306 1307 1308 1309 1310
 *	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
1311
 */
1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322
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;

1323
	rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1324 1325 1326 1327 1328 1329
	call_netdevice_notifiers(NETDEV_UP, dev);

	return ret;
}
EXPORT_SYMBOL(dev_open);

1330
static int __dev_close_many(struct list_head *head)
L
Linus Torvalds 已提交
1331
{
1332
	struct net_device *dev;
1333

1334
	ASSERT_RTNL();
1335 1336
	might_sleep();

1337
	list_for_each_entry(dev, head, close_list) {
1338
		/* Temporarily disable netpoll until the interface is down */
1339
		netpoll_poll_disable(dev);
1340

1341
		call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
L
Linus Torvalds 已提交
1342

1343
		clear_bit(__LINK_STATE_START, &dev->state);
L
Linus Torvalds 已提交
1344

1345 1346 1347 1348 1349 1350
		/* 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.
		 */
1351
		smp_mb__after_atomic(); /* Commit netif_running(). */
1352
	}
L
Linus Torvalds 已提交
1353

1354
	dev_deactivate_many(head);
1355

1356
	list_for_each_entry(dev, head, close_list) {
1357
		const struct net_device_ops *ops = dev->netdev_ops;
L
Linus Torvalds 已提交
1358

1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369
		/*
		 *	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;
1370
		netpoll_poll_enable(dev);
1371 1372 1373 1374 1375 1376 1377
	}

	return 0;
}

static int __dev_close(struct net_device *dev)
{
1378
	int retval;
1379 1380
	LIST_HEAD(single);

1381
	list_add(&dev->close_list, &single);
1382 1383
	retval = __dev_close_many(&single);
	list_del(&single);
1384

1385
	return retval;
1386 1387
}

1388
int dev_close_many(struct list_head *head, bool unlink)
1389 1390
{
	struct net_device *dev, *tmp;
L
Linus Torvalds 已提交
1391

1392 1393
	/* Remove the devices that don't need to be closed */
	list_for_each_entry_safe(dev, tmp, head, close_list)
1394
		if (!(dev->flags & IFF_UP))
1395
			list_del_init(&dev->close_list);
1396 1397

	__dev_close_many(head);
L
Linus Torvalds 已提交
1398

1399
	list_for_each_entry_safe(dev, tmp, head, close_list) {
1400
		rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1401
		call_netdevice_notifiers(NETDEV_DOWN, dev);
1402 1403
		if (unlink)
			list_del_init(&dev->close_list);
1404
	}
1405 1406 1407

	return 0;
}
1408
EXPORT_SYMBOL(dev_close_many);
1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420

/**
 *	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)
{
1421 1422
	if (dev->flags & IFF_UP) {
		LIST_HEAD(single);
L
Linus Torvalds 已提交
1423

1424
		list_add(&dev->close_list, &single);
1425
		dev_close_many(&single, true);
1426 1427
		list_del(&single);
	}
1428
	return 0;
L
Linus Torvalds 已提交
1429
}
E
Eric Dumazet 已提交
1430
EXPORT_SYMBOL(dev_close);
L
Linus Torvalds 已提交
1431 1432


1433 1434 1435 1436 1437 1438 1439 1440 1441 1442
/**
 *	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)
{
1443 1444
	struct net_device *lower_dev;
	struct list_head *iter;
1445

M
Michał Mirosław 已提交
1446 1447
	dev->wanted_features &= ~NETIF_F_LRO;
	netdev_update_features(dev);
1448

1449 1450
	if (unlikely(dev->features & NETIF_F_LRO))
		netdev_WARN(dev, "failed to disable LRO!\n");
1451 1452 1453

	netdev_for_each_lower_dev(dev, lower_dev, iter)
		dev_disable_lro(lower_dev);
1454 1455 1456
}
EXPORT_SYMBOL(dev_disable_lro);

1457 1458 1459 1460 1461 1462 1463 1464
static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
				   struct net_device *dev)
{
	struct netdev_notifier_info info;

	netdev_notifier_info_init(&info, dev);
	return nb->notifier_call(nb, val, &info);
}
1465

1466 1467
static int dev_boot_phase = 1;

L
Linus Torvalds 已提交
1468 1469 1470 1471 1472 1473 1474 1475 1476 1477
/**
 *	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
1478
 *	to the new notifier to allow device to have a race free
L
Linus Torvalds 已提交
1479 1480 1481 1482 1483 1484
 *	view of the network device list.
 */

int register_netdevice_notifier(struct notifier_block *nb)
{
	struct net_device *dev;
1485
	struct net_device *last;
1486
	struct net *net;
L
Linus Torvalds 已提交
1487 1488 1489
	int err;

	rtnl_lock();
1490
	err = raw_notifier_chain_register(&netdev_chain, nb);
1491 1492
	if (err)
		goto unlock;
1493 1494 1495 1496
	if (dev_boot_phase)
		goto unlock;
	for_each_net(net) {
		for_each_netdev(net, dev) {
1497
			err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
1498 1499 1500 1501 1502 1503
			err = notifier_to_errno(err);
			if (err)
				goto rollback;

			if (!(dev->flags & IFF_UP))
				continue;
L
Linus Torvalds 已提交
1504

1505
			call_netdevice_notifier(nb, NETDEV_UP, dev);
1506
		}
L
Linus Torvalds 已提交
1507
	}
1508 1509

unlock:
L
Linus Torvalds 已提交
1510 1511
	rtnl_unlock();
	return err;
1512 1513 1514

rollback:
	last = dev;
1515 1516 1517
	for_each_net(net) {
		for_each_netdev(net, dev) {
			if (dev == last)
1518
				goto outroll;
1519

1520
			if (dev->flags & IFF_UP) {
1521 1522 1523
				call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
							dev);
				call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1524
			}
1525
			call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1526 1527
		}
	}
1528

1529
outroll:
1530
	raw_notifier_chain_unregister(&netdev_chain, nb);
1531
	goto unlock;
L
Linus Torvalds 已提交
1532
}
E
Eric Dumazet 已提交
1533
EXPORT_SYMBOL(register_netdevice_notifier);
L
Linus Torvalds 已提交
1534 1535 1536 1537 1538 1539 1540 1541 1542

/**
 *	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.
1543 1544 1545 1546
 *
 * 	After unregistering unregister and down device events are synthesized
 *	for all devices on the device list to the removed notifier to remove
 *	the need for special case cleanup code.
L
Linus Torvalds 已提交
1547 1548 1549 1550
 */

int unregister_netdevice_notifier(struct notifier_block *nb)
{
1551 1552
	struct net_device *dev;
	struct net *net;
1553 1554 1555
	int err;

	rtnl_lock();
1556
	err = raw_notifier_chain_unregister(&netdev_chain, nb);
1557 1558 1559 1560 1561 1562
	if (err)
		goto unlock;

	for_each_net(net) {
		for_each_netdev(net, dev) {
			if (dev->flags & IFF_UP) {
1563 1564 1565
				call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
							dev);
				call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1566
			}
1567
			call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1568 1569 1570
		}
	}
unlock:
1571 1572
	rtnl_unlock();
	return err;
L
Linus Torvalds 已提交
1573
}
E
Eric Dumazet 已提交
1574
EXPORT_SYMBOL(unregister_netdevice_notifier);
L
Linus Torvalds 已提交
1575

1576 1577 1578 1579 1580 1581 1582 1583 1584 1585
/**
 *	call_netdevice_notifiers_info - call all network notifier blocks
 *	@val: value passed unmodified to notifier function
 *	@dev: net_device pointer passed unmodified to notifier function
 *	@info: notifier information data
 *
 *	Call all network notifier blocks.  Parameters and return value
 *	are as for raw_notifier_call_chain().
 */

S
stephen hemminger 已提交
1586 1587 1588
static int call_netdevice_notifiers_info(unsigned long val,
					 struct net_device *dev,
					 struct netdev_notifier_info *info)
1589 1590 1591 1592 1593 1594
{
	ASSERT_RTNL();
	netdev_notifier_info_init(info, dev);
	return raw_notifier_call_chain(&netdev_chain, val, info);
}

L
Linus Torvalds 已提交
1595 1596 1597
/**
 *	call_netdevice_notifiers - call all network notifier blocks
 *      @val: value passed unmodified to notifier function
1598
 *      @dev: net_device pointer passed unmodified to notifier function
L
Linus Torvalds 已提交
1599 1600
 *
 *	Call all network notifier blocks.  Parameters and return value
1601
 *	are as for raw_notifier_call_chain().
L
Linus Torvalds 已提交
1602 1603
 */

1604
int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
L
Linus Torvalds 已提交
1605
{
1606 1607 1608
	struct netdev_notifier_info info;

	return call_netdevice_notifiers_info(val, dev, &info);
L
Linus Torvalds 已提交
1609
}
1610
EXPORT_SYMBOL(call_netdevice_notifiers);
L
Linus Torvalds 已提交
1611

1612
static struct static_key netstamp_needed __read_mostly;
1613
#ifdef HAVE_JUMP_LABEL
1614
/* We are not allowed to call static_key_slow_dec() from irq context
1615
 * If net_disable_timestamp() is called from irq context, defer the
1616
 * static_key_slow_dec() calls.
1617 1618 1619
 */
static atomic_t netstamp_needed_deferred;
#endif
L
Linus Torvalds 已提交
1620 1621 1622

void net_enable_timestamp(void)
{
1623 1624 1625 1626 1627
#ifdef HAVE_JUMP_LABEL
	int deferred = atomic_xchg(&netstamp_needed_deferred, 0);

	if (deferred) {
		while (--deferred)
1628
			static_key_slow_dec(&netstamp_needed);
1629 1630 1631
		return;
	}
#endif
1632
	static_key_slow_inc(&netstamp_needed);
L
Linus Torvalds 已提交
1633
}
E
Eric Dumazet 已提交
1634
EXPORT_SYMBOL(net_enable_timestamp);
L
Linus Torvalds 已提交
1635 1636 1637

void net_disable_timestamp(void)
{
1638 1639 1640 1641 1642 1643
#ifdef HAVE_JUMP_LABEL
	if (in_interrupt()) {
		atomic_inc(&netstamp_needed_deferred);
		return;
	}
#endif
1644
	static_key_slow_dec(&netstamp_needed);
L
Linus Torvalds 已提交
1645
}
E
Eric Dumazet 已提交
1646
EXPORT_SYMBOL(net_disable_timestamp);
L
Linus Torvalds 已提交
1647

E
Eric Dumazet 已提交
1648
static inline void net_timestamp_set(struct sk_buff *skb)
L
Linus Torvalds 已提交
1649
{
1650
	skb->tstamp.tv64 = 0;
1651
	if (static_key_false(&netstamp_needed))
1652
		__net_timestamp(skb);
L
Linus Torvalds 已提交
1653 1654
}

1655
#define net_timestamp_check(COND, SKB)			\
1656
	if (static_key_false(&netstamp_needed)) {		\
1657 1658 1659
		if ((COND) && !(SKB)->tstamp.tv64)	\
			__net_timestamp(SKB);		\
	}						\
E
Eric Dumazet 已提交
1660

1661
bool is_skb_forwardable(struct net_device *dev, struct sk_buff *skb)
1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679
{
	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;
}
1680
EXPORT_SYMBOL_GPL(is_skb_forwardable);
1681

H
Herbert Xu 已提交
1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698
int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
{
	if (skb_shinfo(skb)->tx_flags & SKBTX_DEV_ZEROCOPY) {
		if (skb_copy_ubufs(skb, GFP_ATOMIC)) {
			atomic_long_inc(&dev->rx_dropped);
			kfree_skb(skb);
			return NET_RX_DROP;
		}
	}

	if (unlikely(!is_skb_forwardable(dev, skb))) {
		atomic_long_inc(&dev->rx_dropped);
		kfree_skb(skb);
		return NET_RX_DROP;
	}

	skb_scrub_packet(skb, true);
1699
	skb->priority = 0;
H
Herbert Xu 已提交
1700
	skb->protocol = eth_type_trans(skb, dev);
1701
	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
H
Herbert Xu 已提交
1702 1703 1704 1705 1706

	return 0;
}
EXPORT_SYMBOL_GPL(__dev_forward_skb);

1707 1708 1709 1710 1711 1712 1713 1714
/**
 * dev_forward_skb - loopback an skb to another netif
 *
 * @dev: destination network device
 * @skb: buffer to forward
 *
 * return values:
 *	NET_RX_SUCCESS	(no congestion)
1715
 *	NET_RX_DROP     (packet was dropped, but freed)
1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726
 *
 * 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)
{
H
Herbert Xu 已提交
1727
	return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb);
1728 1729 1730
}
EXPORT_SYMBOL_GPL(dev_forward_skb);

1731 1732 1733 1734
static inline int deliver_skb(struct sk_buff *skb,
			      struct packet_type *pt_prev,
			      struct net_device *orig_dev)
{
1735 1736
	if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
		return -ENOMEM;
1737 1738 1739 1740
	atomic_inc(&skb->users);
	return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
}

1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757
static inline void deliver_ptype_list_skb(struct sk_buff *skb,
					  struct packet_type **pt,
					  struct net_device *dev, __be16 type,
					  struct list_head *ptype_list)
{
	struct packet_type *ptype, *pt_prev = *pt;

	list_for_each_entry_rcu(ptype, ptype_list, list) {
		if (ptype->type != type)
			continue;
		if (pt_prev)
			deliver_skb(skb, pt_prev, dev);
		pt_prev = ptype;
	}
	*pt = pt_prev;
}

1758 1759
static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
{
1760
	if (!ptype->af_packet_priv || !skb->sk)
1761 1762 1763 1764 1765 1766 1767 1768 1769 1770
		return false;

	if (ptype->id_match)
		return ptype->id_match(ptype, skb->sk);
	else if ((struct sock *)ptype->af_packet_priv == skb->sk)
		return true;

	return false;
}

L
Linus Torvalds 已提交
1771 1772 1773 1774 1775
/*
 *	Support routine. Sends outgoing frames to any network
 *	taps currently in use.
 */

1776
static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
L
Linus Torvalds 已提交
1777 1778
{
	struct packet_type *ptype;
1779 1780
	struct sk_buff *skb2 = NULL;
	struct packet_type *pt_prev = NULL;
1781
	struct list_head *ptype_list = &ptype_all;
1782

L
Linus Torvalds 已提交
1783
	rcu_read_lock();
1784 1785
again:
	list_for_each_entry_rcu(ptype, ptype_list, list) {
L
Linus Torvalds 已提交
1786 1787 1788
		/* Never send packets back to the socket
		 * they originated from - MvS (miquels@drinkel.ow.org)
		 */
1789 1790
		if (skb_loop_sk(ptype, skb))
			continue;
1791

1792 1793 1794 1795 1796
		if (pt_prev) {
			deliver_skb(skb2, pt_prev, skb->dev);
			pt_prev = ptype;
			continue;
		}
L
Linus Torvalds 已提交
1797

1798 1799 1800 1801
		/* need to clone skb, done only once */
		skb2 = skb_clone(skb, GFP_ATOMIC);
		if (!skb2)
			goto out_unlock;
1802

1803
		net_timestamp_set(skb2);
L
Linus Torvalds 已提交
1804

1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816
		/* skb->nh should be correctly
		 * set by sender, so that the second statement is
		 * just protection against buggy protocols.
		 */
		skb_reset_mac_header(skb2);

		if (skb_network_header(skb2) < skb2->data ||
		    skb_network_header(skb2) > skb_tail_pointer(skb2)) {
			net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
					     ntohs(skb2->protocol),
					     dev->name);
			skb_reset_network_header(skb2);
L
Linus Torvalds 已提交
1817
		}
1818 1819 1820 1821 1822 1823 1824 1825 1826

		skb2->transport_header = skb2->network_header;
		skb2->pkt_type = PACKET_OUTGOING;
		pt_prev = ptype;
	}

	if (ptype_list == &ptype_all) {
		ptype_list = &dev->ptype_all;
		goto again;
L
Linus Torvalds 已提交
1827
	}
1828
out_unlock:
1829 1830
	if (pt_prev)
		pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
L
Linus Torvalds 已提交
1831 1832 1833
	rcu_read_unlock();
}

1834 1835
/**
 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846
 * @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
1847
static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1848 1849 1850 1851 1852 1853
{
	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) {
1854
		pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
1855 1856 1857 1858 1859 1860 1861 1862 1863 1864
		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) {
1865 1866
			pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
				i, q);
1867 1868 1869 1870 1871
			netdev_set_prio_tc_map(dev, i, 0);
		}
	}
}

1872 1873 1874 1875 1876
#ifdef CONFIG_XPS
static DEFINE_MUTEX(xps_map_mutex);
#define xmap_dereference(P)		\
	rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))

1877 1878
static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps,
					int cpu, u16 index)
1879
{
1880 1881
	struct xps_map *map = NULL;
	int pos;
1882

1883 1884
	if (dev_maps)
		map = xmap_dereference(dev_maps->cpu_map[cpu]);
1885

1886 1887
	for (pos = 0; map && pos < map->len; pos++) {
		if (map->queues[pos] == index) {
1888 1889 1890
			if (map->len > 1) {
				map->queues[pos] = map->queues[--map->len];
			} else {
1891
				RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL);
1892 1893 1894
				kfree_rcu(map, rcu);
				map = NULL;
			}
1895
			break;
1896 1897 1898
		}
	}

1899 1900 1901
	return map;
}

1902
static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
1903 1904
{
	struct xps_dev_maps *dev_maps;
1905
	int cpu, i;
1906 1907 1908 1909 1910 1911 1912 1913 1914
	bool active = false;

	mutex_lock(&xps_map_mutex);
	dev_maps = xmap_dereference(dev->xps_maps);

	if (!dev_maps)
		goto out_no_maps;

	for_each_possible_cpu(cpu) {
1915 1916 1917 1918 1919
		for (i = index; i < dev->num_tx_queues; i++) {
			if (!remove_xps_queue(dev_maps, cpu, i))
				break;
		}
		if (i == dev->num_tx_queues)
1920 1921 1922 1923
			active = true;
	}

	if (!active) {
1924 1925 1926 1927
		RCU_INIT_POINTER(dev->xps_maps, NULL);
		kfree_rcu(dev_maps, rcu);
	}

1928 1929 1930 1931
	for (i = index; i < dev->num_tx_queues; i++)
		netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
					     NUMA_NO_NODE);

1932 1933 1934 1935
out_no_maps:
	mutex_unlock(&xps_map_mutex);
}

1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970
static struct xps_map *expand_xps_map(struct xps_map *map,
				      int cpu, u16 index)
{
	struct xps_map *new_map;
	int alloc_len = XPS_MIN_MAP_ALLOC;
	int i, pos;

	for (pos = 0; map && pos < map->len; pos++) {
		if (map->queues[pos] != index)
			continue;
		return map;
	}

	/* Need to add queue to this CPU's existing map */
	if (map) {
		if (pos < map->alloc_len)
			return map;

		alloc_len = map->alloc_len * 2;
	}

	/* Need to allocate new map to store queue on this CPU's map */
	new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
			       cpu_to_node(cpu));
	if (!new_map)
		return NULL;

	for (i = 0; i < pos; i++)
		new_map->queues[i] = map->queues[i];
	new_map->alloc_len = alloc_len;
	new_map->len = pos;

	return new_map;
}

1971 1972
int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
			u16 index)
1973
{
1974
	struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
1975 1976
	struct xps_map *map, *new_map;
	int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES);
1977 1978
	int cpu, numa_node_id = -2;
	bool active = false;
1979 1980 1981 1982 1983

	mutex_lock(&xps_map_mutex);

	dev_maps = xmap_dereference(dev->xps_maps);

1984 1985 1986 1987 1988 1989 1990
	/* allocate memory for queue storage */
	for_each_online_cpu(cpu) {
		if (!cpumask_test_cpu(cpu, mask))
			continue;

		if (!new_dev_maps)
			new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
1991 1992
		if (!new_dev_maps) {
			mutex_unlock(&xps_map_mutex);
1993
			return -ENOMEM;
1994
		}
1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008

		map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
				 NULL;

		map = expand_xps_map(map, cpu, index);
		if (!map)
			goto error;

		RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
	}

	if (!new_dev_maps)
		goto out_no_new_maps;

2009
	for_each_possible_cpu(cpu) {
2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
		if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) {
			/* add queue to CPU maps */
			int pos = 0;

			map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
			while ((pos < map->len) && (map->queues[pos] != index))
				pos++;

			if (pos == map->len)
				map->queues[map->len++] = index;
2020 2021 2022 2023 2024 2025
#ifdef CONFIG_NUMA
			if (numa_node_id == -2)
				numa_node_id = cpu_to_node(cpu);
			else if (numa_node_id != cpu_to_node(cpu))
				numa_node_id = -1;
#endif
2026 2027 2028 2029
		} else if (dev_maps) {
			/* fill in the new device map from the old device map */
			map = xmap_dereference(dev_maps->cpu_map[cpu]);
			RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
2030
		}
2031

2032 2033
	}

2034 2035
	rcu_assign_pointer(dev->xps_maps, new_dev_maps);

2036
	/* Cleanup old maps */
2037 2038 2039 2040 2041 2042 2043
	if (dev_maps) {
		for_each_possible_cpu(cpu) {
			new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
			map = xmap_dereference(dev_maps->cpu_map[cpu]);
			if (map && map != new_map)
				kfree_rcu(map, rcu);
		}
2044

2045
		kfree_rcu(dev_maps, rcu);
2046 2047
	}

2048 2049
	dev_maps = new_dev_maps;
	active = true;
2050

2051 2052
out_no_new_maps:
	/* update Tx queue numa node */
2053 2054 2055 2056
	netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
				     (numa_node_id >= 0) ? numa_node_id :
				     NUMA_NO_NODE);

2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075
	if (!dev_maps)
		goto out_no_maps;

	/* removes queue from unused CPUs */
	for_each_possible_cpu(cpu) {
		if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu))
			continue;

		if (remove_xps_queue(dev_maps, cpu, index))
			active = true;
	}

	/* free map if not active */
	if (!active) {
		RCU_INIT_POINTER(dev->xps_maps, NULL);
		kfree_rcu(dev_maps, rcu);
	}

out_no_maps:
2076 2077 2078 2079
	mutex_unlock(&xps_map_mutex);

	return 0;
error:
2080 2081 2082 2083 2084 2085 2086 2087 2088
	/* remove any maps that we added */
	for_each_possible_cpu(cpu) {
		new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
		map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
				 NULL;
		if (new_map && new_map != map)
			kfree(new_map);
	}

2089 2090 2091 2092 2093 2094 2095 2096
	mutex_unlock(&xps_map_mutex);

	kfree(new_dev_maps);
	return -ENOMEM;
}
EXPORT_SYMBOL(netif_set_xps_queue);

#endif
2097 2098 2099 2100
/*
 * 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.
 */
2101
int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2102
{
T
Tom Herbert 已提交
2103 2104
	int rc;

2105 2106
	if (txq < 1 || txq > dev->num_tx_queues)
		return -EINVAL;
2107

2108 2109
	if (dev->reg_state == NETREG_REGISTERED ||
	    dev->reg_state == NETREG_UNREGISTERING) {
2110 2111
		ASSERT_RTNL();

T
Tom Herbert 已提交
2112 2113
		rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
						  txq);
T
Tom Herbert 已提交
2114 2115 2116
		if (rc)
			return rc;

2117 2118 2119
		if (dev->num_tc)
			netif_setup_tc(dev, txq);

2120
		if (txq < dev->real_num_tx_queues) {
2121
			qdisc_reset_all_tx_gt(dev, txq);
2122 2123 2124 2125
#ifdef CONFIG_XPS
			netif_reset_xps_queues_gt(dev, txq);
#endif
		}
2126
	}
2127 2128 2129

	dev->real_num_tx_queues = txq;
	return 0;
2130 2131
}
EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2132

2133
#ifdef CONFIG_SYSFS
2134 2135 2136 2137 2138 2139 2140
/**
 *	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
2141 2142
 *	negative error code.  If called before registration, it always
 *	succeeds.
2143 2144 2145 2146 2147
 */
int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
{
	int rc;

T
Tom Herbert 已提交
2148 2149 2150
	if (rxq < 1 || rxq > dev->num_rx_queues)
		return -EINVAL;

2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165
	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

2166 2167
/**
 * netif_get_num_default_rss_queues - default number of RSS queues
2168 2169 2170 2171
 *
 * This routine should set an upper limit on the number of RSS queues
 * used by default by multiqueue devices.
 */
2172
int netif_get_num_default_rss_queues(void)
2173 2174 2175 2176 2177
{
	return min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
}
EXPORT_SYMBOL(netif_get_num_default_rss_queues);

2178
static inline void __netif_reschedule(struct Qdisc *q)
2179
{
2180 2181
	struct softnet_data *sd;
	unsigned long flags;
2182

2183
	local_irq_save(flags);
2184
	sd = this_cpu_ptr(&softnet_data);
2185 2186 2187
	q->next_sched = NULL;
	*sd->output_queue_tailp = q;
	sd->output_queue_tailp = &q->next_sched;
2188 2189 2190 2191 2192 2193 2194 2195
	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);
2196 2197 2198
}
EXPORT_SYMBOL(__netif_schedule);

2199 2200 2201 2202 2203
struct dev_kfree_skb_cb {
	enum skb_free_reason reason;
};

static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
2204
{
2205 2206 2207
	return (struct dev_kfree_skb_cb *)skb->cb;
}

2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254
void netif_schedule_queue(struct netdev_queue *txq)
{
	rcu_read_lock();
	if (!(txq->state & QUEUE_STATE_ANY_XOFF)) {
		struct Qdisc *q = rcu_dereference(txq->qdisc);

		__netif_schedule(q);
	}
	rcu_read_unlock();
}
EXPORT_SYMBOL(netif_schedule_queue);

/**
 *	netif_wake_subqueue - allow sending packets on subqueue
 *	@dev: network device
 *	@queue_index: sub queue index
 *
 * Resume individual transmit queue of a device with multiple transmit queues.
 */
void netif_wake_subqueue(struct net_device *dev, u16 queue_index)
{
	struct netdev_queue *txq = netdev_get_tx_queue(dev, queue_index);

	if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &txq->state)) {
		struct Qdisc *q;

		rcu_read_lock();
		q = rcu_dereference(txq->qdisc);
		__netif_schedule(q);
		rcu_read_unlock();
	}
}
EXPORT_SYMBOL(netif_wake_subqueue);

void netif_tx_wake_queue(struct netdev_queue *dev_queue)
{
	if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) {
		struct Qdisc *q;

		rcu_read_lock();
		q = rcu_dereference(dev_queue->qdisc);
		__netif_schedule(q);
		rcu_read_unlock();
	}
}
EXPORT_SYMBOL(netif_tx_wake_queue);

2255
void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2256
{
2257
	unsigned long flags;
2258

2259 2260 2261 2262 2263
	if (likely(atomic_read(&skb->users) == 1)) {
		smp_rmb();
		atomic_set(&skb->users, 0);
	} else if (likely(!atomic_dec_and_test(&skb->users))) {
		return;
2264
	}
2265 2266 2267 2268 2269 2270
	get_kfree_skb_cb(skb)->reason = reason;
	local_irq_save(flags);
	skb->next = __this_cpu_read(softnet_data.completion_queue);
	__this_cpu_write(softnet_data.completion_queue, skb);
	raise_softirq_irqoff(NET_TX_SOFTIRQ);
	local_irq_restore(flags);
2271
}
2272
EXPORT_SYMBOL(__dev_kfree_skb_irq);
2273

2274
void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2275 2276
{
	if (in_irq() || irqs_disabled())
2277
		__dev_kfree_skb_irq(skb, reason);
2278 2279 2280
	else
		dev_kfree_skb(skb);
}
2281
EXPORT_SYMBOL(__dev_kfree_skb_any);
2282 2283


2284 2285 2286 2287 2288 2289
/**
 * netif_device_detach - mark device as removed
 * @dev: network device
 *
 * Mark device as removed from system and therefore no longer available.
 */
2290 2291 2292 2293
void netif_device_detach(struct net_device *dev)
{
	if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
	    netif_running(dev)) {
2294
		netif_tx_stop_all_queues(dev);
2295 2296 2297 2298
	}
}
EXPORT_SYMBOL(netif_device_detach);

2299 2300 2301 2302 2303 2304
/**
 * netif_device_attach - mark device as attached
 * @dev: network device
 *
 * Mark device as attached from system and restart if needed.
 */
2305 2306 2307 2308
void netif_device_attach(struct net_device *dev)
{
	if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
	    netif_running(dev)) {
2309
		netif_tx_wake_all_queues(dev);
2310
		__netdev_watchdog_up(dev);
2311 2312 2313 2314
	}
}
EXPORT_SYMBOL(netif_device_attach);

2315 2316
static void skb_warn_bad_offload(const struct sk_buff *skb)
{
2317
	static const netdev_features_t null_features = 0;
2318 2319 2320
	struct net_device *dev = skb->dev;
	const char *driver = "";

2321 2322 2323
	if (!net_ratelimit())
		return;

2324 2325 2326 2327 2328
	if (dev && dev->dev.parent)
		driver = dev_driver_string(dev->dev.parent);

	WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
	     "gso_type=%d ip_summed=%d\n",
2329 2330
	     driver, dev ? &dev->features : &null_features,
	     skb->sk ? &skb->sk->sk_route_caps : &null_features,
2331 2332 2333 2334
	     skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
	     skb_shinfo(skb)->gso_type, skb->ip_summed);
}

L
Linus Torvalds 已提交
2335 2336 2337 2338
/*
 * Invalidate hardware checksum when packet is to be mangled, and
 * complete checksum manually on outgoing path.
 */
2339
int skb_checksum_help(struct sk_buff *skb)
L
Linus Torvalds 已提交
2340
{
2341
	__wsum csum;
2342
	int ret = 0, offset;
L
Linus Torvalds 已提交
2343

2344
	if (skb->ip_summed == CHECKSUM_COMPLETE)
2345 2346 2347
		goto out_set_summed;

	if (unlikely(skb_shinfo(skb)->gso_size)) {
2348 2349
		skb_warn_bad_offload(skb);
		return -EINVAL;
L
Linus Torvalds 已提交
2350 2351
	}

2352 2353 2354 2355 2356 2357 2358 2359 2360
	/* Before computing a checksum, we should make sure no frag could
	 * be modified by an external entity : checksum could be wrong.
	 */
	if (skb_has_shared_frag(skb)) {
		ret = __skb_linearize(skb);
		if (ret)
			goto out;
	}

2361
	offset = skb_checksum_start_offset(skb);
2362 2363 2364 2365 2366 2367 2368 2369
	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
2370 2371 2372 2373 2374
		ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
		if (ret)
			goto out;
	}

2375
	*(__sum16 *)(skb->data + offset) = csum_fold(csum);
2376
out_set_summed:
L
Linus Torvalds 已提交
2377
	skb->ip_summed = CHECKSUM_NONE;
2378
out:
L
Linus Torvalds 已提交
2379 2380
	return ret;
}
E
Eric Dumazet 已提交
2381
EXPORT_SYMBOL(skb_checksum_help);
L
Linus Torvalds 已提交
2382

2383
__be16 skb_network_protocol(struct sk_buff *skb, int *depth)
2384
{
A
Al Viro 已提交
2385
	__be16 type = skb->protocol;
2386

2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397
	/* Tunnel gso handlers can set protocol to ethernet. */
	if (type == htons(ETH_P_TEB)) {
		struct ethhdr *eth;

		if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
			return 0;

		eth = (struct ethhdr *)skb_mac_header(skb);
		type = eth->h_proto;
	}

2398
	return __vlan_get_protocol(skb, type, depth);
2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410
}

/**
 *	skb_mac_gso_segment - mac layer segmentation handler.
 *	@skb: buffer to segment
 *	@features: features for the output path (see dev->features)
 */
struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
				    netdev_features_t features)
{
	struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
	struct packet_offload *ptype;
2411 2412
	int vlan_depth = skb->mac_len;
	__be16 type = skb_network_protocol(skb, &vlan_depth);
2413 2414 2415 2416

	if (unlikely(!type))
		return ERR_PTR(-EINVAL);

2417
	__skb_pull(skb, vlan_depth);
2418 2419

	rcu_read_lock();
2420
	list_for_each_entry_rcu(ptype, &offload_base, list) {
2421 2422
		if (ptype->type == type && ptype->callbacks.gso_segment) {
			segs = ptype->callbacks.gso_segment(skb, features);
2423 2424 2425 2426 2427
			break;
		}
	}
	rcu_read_unlock();

2428
	__skb_push(skb, skb->data - skb_mac_header(skb));
2429

2430 2431
	return segs;
}
2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463
EXPORT_SYMBOL(skb_mac_gso_segment);


/* openvswitch calls this on rx path, so we need a different check.
 */
static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
{
	if (tx_path)
		return skb->ip_summed != CHECKSUM_PARTIAL;
	else
		return skb->ip_summed == CHECKSUM_NONE;
}

/**
 *	__skb_gso_segment - Perform segmentation on skb.
 *	@skb: buffer to segment
 *	@features: features for the output path (see dev->features)
 *	@tx_path: whether it is called in TX path
 *
 *	This function segments the given skb and returns a list of segments.
 *
 *	It may return NULL if the skb requires no segmentation.  This is
 *	only possible when GSO is used for verifying header integrity.
 */
struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
				  netdev_features_t features, bool tx_path)
{
	if (unlikely(skb_needs_check(skb, tx_path))) {
		int err;

		skb_warn_bad_offload(skb);

2464 2465
		err = skb_cow_head(skb, 0);
		if (err < 0)
2466 2467 2468
			return ERR_PTR(err);
	}

2469
	SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2470 2471
	SKB_GSO_CB(skb)->encap_level = 0;

2472 2473 2474 2475 2476
	skb_reset_mac_header(skb);
	skb_reset_mac_len(skb);

	return skb_mac_gso_segment(skb, features);
}
2477
EXPORT_SYMBOL(__skb_gso_segment);
2478

2479 2480 2481 2482 2483
/* Take action when hardware reception checksum errors are detected. */
#ifdef CONFIG_BUG
void netdev_rx_csum_fault(struct net_device *dev)
{
	if (net_ratelimit()) {
2484
		pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2485 2486 2487 2488 2489 2490
		dump_stack();
	}
}
EXPORT_SYMBOL(netdev_rx_csum_fault);
#endif

L
Linus Torvalds 已提交
2491 2492 2493 2494 2495
/* 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.
 */

2496
static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
L
Linus Torvalds 已提交
2497
{
2498
#ifdef CONFIG_HIGHMEM
L
Linus Torvalds 已提交
2499
	int i;
2500
	if (!(dev->features & NETIF_F_HIGHDMA)) {
2501 2502 2503
		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
			if (PageHighMem(skb_frag_page(frag)))
2504
				return 1;
2505
		}
2506
	}
L
Linus Torvalds 已提交
2507

2508 2509
	if (PCI_DMA_BUS_IS_PHYS) {
		struct device *pdev = dev->dev.parent;
L
Linus Torvalds 已提交
2510

E
Eric Dumazet 已提交
2511 2512
		if (!pdev)
			return 0;
2513
		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2514 2515
			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
			dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2516 2517 2518 2519
			if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
				return 1;
		}
	}
2520
#endif
L
Linus Torvalds 已提交
2521 2522 2523
	return 0;
}

2524 2525 2526
/* If MPLS offload request, verify we are testing hardware MPLS features
 * instead of standard features for the netdev.
 */
P
Pravin B Shelar 已提交
2527
#if IS_ENABLED(CONFIG_NET_MPLS_GSO)
2528 2529 2530 2531
static netdev_features_t net_mpls_features(struct sk_buff *skb,
					   netdev_features_t features,
					   __be16 type)
{
2532
	if (eth_p_mpls(type))
2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545
		features &= skb->dev->mpls_features;

	return features;
}
#else
static netdev_features_t net_mpls_features(struct sk_buff *skb,
					   netdev_features_t features,
					   __be16 type)
{
	return features;
}
#endif

2546
static netdev_features_t harmonize_features(struct sk_buff *skb,
2547
	netdev_features_t features)
2548
{
2549
	int tmp;
2550 2551 2552 2553
	__be16 type;

	type = skb_network_protocol(skb, &tmp);
	features = net_mpls_features(skb, features, type);
2554

2555
	if (skb->ip_summed != CHECKSUM_NONE &&
2556
	    !can_checksum_protocol(features, type)) {
2557
		features &= ~NETIF_F_ALL_CSUM;
2558
	} else if (illegal_highdma(skb->dev, skb)) {
2559 2560 2561 2562 2563 2564
		features &= ~NETIF_F_SG;
	}

	return features;
}

2565
netdev_features_t netif_skb_features(struct sk_buff *skb)
2566
{
2567
	struct net_device *dev = skb->dev;
2568 2569
	netdev_features_t features = dev->features;
	u16 gso_segs = skb_shinfo(skb)->gso_segs;
2570

2571
	if (gso_segs > dev->gso_max_segs || gso_segs < dev->gso_min_segs)
2572 2573
		features &= ~NETIF_F_GSO_MASK;

2574 2575 2576 2577 2578 2579 2580
	/* If encapsulation offload request, verify we are testing
	 * hardware encapsulation features instead of standard
	 * features for the netdev
	 */
	if (skb->encapsulation)
		features &= dev->hw_enc_features;

2581 2582 2583 2584 2585 2586 2587
	if (skb_vlan_tagged(skb))
		features = netdev_intersect_features(features,
						     dev->vlan_features |
						     NETIF_F_HW_VLAN_CTAG_TX |
						     NETIF_F_HW_VLAN_STAG_TX);
	else
		goto finalize;
2588

2589
	if (skb_vlan_tagged_multi(skb))
2590 2591 2592 2593 2594 2595 2596
		features = netdev_intersect_features(features,
						     NETIF_F_SG |
						     NETIF_F_HIGHDMA |
						     NETIF_F_FRAGLIST |
						     NETIF_F_GEN_CSUM |
						     NETIF_F_HW_VLAN_CTAG_TX |
						     NETIF_F_HW_VLAN_STAG_TX);
2597

2598 2599 2600 2601 2602
finalize:
	if (dev->netdev_ops->ndo_features_check)
		features &= dev->netdev_ops->ndo_features_check(skb, dev,
								features);

2603
	return harmonize_features(skb, features);
2604
}
2605
EXPORT_SYMBOL(netif_skb_features);
2606

2607
static int xmit_one(struct sk_buff *skb, struct net_device *dev,
2608
		    struct netdev_queue *txq, bool more)
2609
{
2610 2611
	unsigned int len;
	int rc;
2612

2613
	if (!list_empty(&ptype_all) || !list_empty(&dev->ptype_all))
2614
		dev_queue_xmit_nit(skb, dev);
2615

2616 2617
	len = skb->len;
	trace_net_dev_start_xmit(skb, dev);
2618
	rc = netdev_start_xmit(skb, dev, txq, more);
2619
	trace_net_dev_xmit(skb, rc, dev, len);
E
Eric Dumazet 已提交
2620

2621 2622
	return rc;
}
2623

2624 2625
struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev,
				    struct netdev_queue *txq, int *ret)
2626 2627 2628
{
	struct sk_buff *skb = first;
	int rc = NETDEV_TX_OK;
2629

2630 2631
	while (skb) {
		struct sk_buff *next = skb->next;
2632

2633
		skb->next = NULL;
2634
		rc = xmit_one(skb, dev, txq, next != NULL);
2635 2636 2637 2638
		if (unlikely(!dev_xmit_complete(rc))) {
			skb->next = next;
			goto out;
		}
2639

2640 2641 2642 2643
		skb = next;
		if (netif_xmit_stopped(txq) && skb) {
			rc = NETDEV_TX_BUSY;
			break;
2644
		}
2645
	}
2646

2647 2648 2649 2650
out:
	*ret = rc;
	return skb;
}
2651

E
Eric Dumazet 已提交
2652 2653
static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
					  netdev_features_t features)
2654
{
2655
	if (skb_vlan_tag_present(skb) &&
2656 2657
	    !vlan_hw_offload_capable(features, skb->vlan_proto))
		skb = __vlan_hwaccel_push_inside(skb);
2658 2659
	return skb;
}
2660

2661
static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev)
2662 2663
{
	netdev_features_t features;
2664

2665 2666
	if (skb->next)
		return skb;
2667

2668 2669 2670 2671
	features = netif_skb_features(skb);
	skb = validate_xmit_vlan(skb, features);
	if (unlikely(!skb))
		goto out_null;
2672

T
Tom Herbert 已提交
2673
	if (netif_needs_gso(dev, skb, features)) {
2674 2675 2676
		struct sk_buff *segs;

		segs = skb_gso_segment(skb, features);
2677
		if (IS_ERR(segs)) {
2678
			goto out_kfree_skb;
2679 2680 2681
		} else if (segs) {
			consume_skb(skb);
			skb = segs;
2682
		}
2683 2684 2685 2686
	} else {
		if (skb_needs_linearize(skb, features) &&
		    __skb_linearize(skb))
			goto out_kfree_skb;
2687

2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701
		/* If packet is not checksummed and device does not
		 * support checksumming for this protocol, complete
		 * checksumming here.
		 */
		if (skb->ip_summed == CHECKSUM_PARTIAL) {
			if (skb->encapsulation)
				skb_set_inner_transport_header(skb,
							       skb_checksum_start_offset(skb));
			else
				skb_set_transport_header(skb,
							 skb_checksum_start_offset(skb));
			if (!(features & NETIF_F_ALL_CSUM) &&
			    skb_checksum_help(skb))
				goto out_kfree_skb;
2702
		}
2703
	}
2704

2705
	return skb;
2706

2707 2708
out_kfree_skb:
	kfree_skb(skb);
2709 2710 2711
out_null:
	return NULL;
}
2712

2713 2714 2715 2716
struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev)
{
	struct sk_buff *next, *head = NULL, *tail;

2717
	for (; skb != NULL; skb = next) {
2718 2719
		next = skb->next;
		skb->next = NULL;
2720 2721 2722 2723

		/* in case skb wont be segmented, point to itself */
		skb->prev = skb;

2724
		skb = validate_xmit_skb(skb, dev);
2725 2726
		if (!skb)
			continue;
2727

2728 2729 2730 2731 2732 2733 2734 2735
		if (!head)
			head = skb;
		else
			tail->next = skb;
		/* If skb was segmented, skb->prev points to
		 * the last segment. If not, it still contains skb.
		 */
		tail = skb->prev;
2736 2737
	}
	return head;
2738 2739
}

2740 2741 2742 2743 2744 2745 2746 2747 2748 2749
static void qdisc_pkt_len_init(struct sk_buff *skb)
{
	const struct skb_shared_info *shinfo = skb_shinfo(skb);

	qdisc_skb_cb(skb)->pkt_len = skb->len;

	/* To get more precise estimation of bytes sent on wire,
	 * we add to pkt_len the headers size of all segments
	 */
	if (shinfo->gso_size)  {
2750
		unsigned int hdr_len;
2751
		u16 gso_segs = shinfo->gso_segs;
2752

2753 2754 2755 2756
		/* mac layer + network layer */
		hdr_len = skb_transport_header(skb) - skb_mac_header(skb);

		/* + transport layer */
2757 2758 2759 2760
		if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
			hdr_len += tcp_hdrlen(skb);
		else
			hdr_len += sizeof(struct udphdr);
2761 2762 2763 2764 2765 2766

		if (shinfo->gso_type & SKB_GSO_DODGY)
			gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
						shinfo->gso_size);

		qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
2767 2768 2769
	}
}

2770 2771 2772 2773 2774
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
2775
	bool contended;
2776 2777
	int rc;

2778
	qdisc_pkt_len_init(skb);
E
Eric Dumazet 已提交
2779
	qdisc_calculate_pkt_len(skb, q);
2780 2781 2782
	/*
	 * Heuristic to force contended enqueues to serialize on a
	 * separate lock before trying to get qdisc main lock.
Y
Ying Xue 已提交
2783 2784
	 * This permits __QDISC___STATE_RUNNING owner to get the lock more
	 * often and dequeue packets faster.
2785
	 */
E
Eric Dumazet 已提交
2786
	contended = qdisc_is_running(q);
2787 2788 2789
	if (unlikely(contended))
		spin_lock(&q->busylock);

2790 2791 2792 2793 2794
	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) &&
2795
		   qdisc_run_begin(q)) {
2796 2797 2798 2799 2800
		/*
		 * 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.
		 */
2801 2802 2803

		qdisc_bstats_update(q, skb);

2804
		if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) {
2805 2806 2807 2808
			if (unlikely(contended)) {
				spin_unlock(&q->busylock);
				contended = false;
			}
2809
			__qdisc_run(q);
2810
		} else
2811
			qdisc_run_end(q);
2812 2813 2814

		rc = NET_XMIT_SUCCESS;
	} else {
E
Eric Dumazet 已提交
2815
		rc = q->enqueue(skb, q) & NET_XMIT_MASK;
2816 2817 2818 2819 2820 2821 2822
		if (qdisc_run_begin(q)) {
			if (unlikely(contended)) {
				spin_unlock(&q->busylock);
				contended = false;
			}
			__qdisc_run(q);
		}
2823 2824
	}
	spin_unlock(root_lock);
2825 2826
	if (unlikely(contended))
		spin_unlock(&q->busylock);
2827 2828 2829
	return rc;
}

2830
#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
2831 2832
static void skb_update_prio(struct sk_buff *skb)
{
I
Igor Maravic 已提交
2833
	struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
2834

2835 2836 2837 2838 2839 2840
	if (!skb->priority && skb->sk && map) {
		unsigned int prioidx = skb->sk->sk_cgrp_prioidx;

		if (prioidx < map->priomap_len)
			skb->priority = map->priomap[prioidx];
	}
2841 2842 2843 2844 2845
}
#else
#define skb_update_prio(skb)
#endif

2846
static DEFINE_PER_CPU(int, xmit_recursion);
2847
#define RECURSION_LIMIT 10
2848

2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863 2864 2865
/**
 *	dev_loopback_xmit - loop back @skb
 *	@skb: buffer to transmit
 */
int dev_loopback_xmit(struct sk_buff *skb)
{
	skb_reset_mac_header(skb);
	__skb_pull(skb, skb_network_offset(skb));
	skb->pkt_type = PACKET_LOOPBACK;
	skb->ip_summed = CHECKSUM_UNNECESSARY;
	WARN_ON(!skb_dst(skb));
	skb_dst_force(skb);
	netif_rx_ni(skb);
	return 0;
}
EXPORT_SYMBOL(dev_loopback_xmit);

2866
/**
2867
 *	__dev_queue_xmit - transmit a buffer
2868
 *	@skb: buffer to transmit
2869
 *	@accel_priv: private data used for L2 forwarding offload
2870 2871 2872 2873 2874 2875 2876 2877 2878 2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891
 *
 *	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
 */
2892
static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
L
Linus Torvalds 已提交
2893 2894
{
	struct net_device *dev = skb->dev;
2895
	struct netdev_queue *txq;
L
Linus Torvalds 已提交
2896 2897 2898
	struct Qdisc *q;
	int rc = -ENOMEM;

2899 2900
	skb_reset_mac_header(skb);

2901 2902 2903
	if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
		__skb_tstamp_tx(skb, NULL, skb->sk, SCM_TSTAMP_SCHED);

2904 2905
	/* Disable soft irqs for various locks below. Also
	 * stops preemption for RCU.
L
Linus Torvalds 已提交
2906
	 */
2907
	rcu_read_lock_bh();
L
Linus Torvalds 已提交
2908

2909 2910
	skb_update_prio(skb);

2911 2912 2913 2914 2915 2916 2917 2918
	/* If device/qdisc don't need skb->dst, release it right now while
	 * its hot in this cpu cache.
	 */
	if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
		skb_dst_drop(skb);
	else
		skb_dst_force(skb);

2919
	txq = netdev_pick_tx(dev, skb, accel_priv);
2920
	q = rcu_dereference_bh(txq->qdisc);
2921

L
Linus Torvalds 已提交
2922
#ifdef CONFIG_NET_CLS_ACT
E
Eric Dumazet 已提交
2923
	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
L
Linus Torvalds 已提交
2924
#endif
2925
	trace_net_dev_queue(skb);
L
Linus Torvalds 已提交
2926
	if (q->enqueue) {
2927
		rc = __dev_xmit_skb(skb, q, dev, txq);
2928
		goto out;
L
Linus Torvalds 已提交
2929 2930 2931 2932 2933
	}

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

H
Herbert Xu 已提交
2934 2935
	   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
2936 2937 2938 2939 2940 2941 2942 2943 2944 2945
	   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 */

2946
		if (txq->xmit_lock_owner != cpu) {
L
Linus Torvalds 已提交
2947

2948 2949 2950
			if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
				goto recursion_alert;

2951 2952 2953 2954
			skb = validate_xmit_skb(skb, dev);
			if (!skb)
				goto drop;

2955
			HARD_TX_LOCK(dev, txq, cpu);
L
Linus Torvalds 已提交
2956

2957
			if (!netif_xmit_stopped(txq)) {
2958
				__this_cpu_inc(xmit_recursion);
2959
				skb = dev_hard_start_xmit(skb, dev, txq, &rc);
2960
				__this_cpu_dec(xmit_recursion);
2961
				if (dev_xmit_complete(rc)) {
2962
					HARD_TX_UNLOCK(dev, txq);
L
Linus Torvalds 已提交
2963 2964 2965
					goto out;
				}
			}
2966
			HARD_TX_UNLOCK(dev, txq);
2967 2968
			net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
					     dev->name);
L
Linus Torvalds 已提交
2969 2970
		} else {
			/* Recursion is detected! It is possible,
2971 2972 2973
			 * unfortunately
			 */
recursion_alert:
2974 2975
			net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
					     dev->name);
L
Linus Torvalds 已提交
2976 2977 2978 2979
		}
	}

	rc = -ENETDOWN;
2980
drop:
2981
	rcu_read_unlock_bh();
L
Linus Torvalds 已提交
2982

2983
	atomic_long_inc(&dev->tx_dropped);
2984
	kfree_skb_list(skb);
L
Linus Torvalds 已提交
2985 2986
	return rc;
out:
2987
	rcu_read_unlock_bh();
L
Linus Torvalds 已提交
2988 2989
	return rc;
}
2990 2991 2992 2993 2994

int dev_queue_xmit(struct sk_buff *skb)
{
	return __dev_queue_xmit(skb, NULL);
}
E
Eric Dumazet 已提交
2995
EXPORT_SYMBOL(dev_queue_xmit);
L
Linus Torvalds 已提交
2996

2997 2998 2999 3000 3001 3002
int dev_queue_xmit_accel(struct sk_buff *skb, void *accel_priv)
{
	return __dev_queue_xmit(skb, accel_priv);
}
EXPORT_SYMBOL(dev_queue_xmit_accel);

L
Linus Torvalds 已提交
3003 3004 3005 3006 3007

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

3008
int netdev_max_backlog __read_mostly = 1000;
E
Eric Dumazet 已提交
3009 3010
EXPORT_SYMBOL(netdev_max_backlog);

E
Eric Dumazet 已提交
3011
int netdev_tstamp_prequeue __read_mostly = 1;
3012 3013
int netdev_budget __read_mostly = 300;
int weight_p __read_mostly = 64;            /* old backlog weight */
L
Linus Torvalds 已提交
3014

E
Eric Dumazet 已提交
3015 3016 3017 3018 3019 3020 3021 3022
/* 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);
}

3023 3024 3025
#ifdef CONFIG_RPS

/* One global table that all flow-based protocols share. */
E
Eric Dumazet 已提交
3026
struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
3027
EXPORT_SYMBOL(rps_sock_flow_table);
3028 3029
u32 rps_cpu_mask __read_mostly;
EXPORT_SYMBOL(rps_cpu_mask);
3030

3031
struct static_key rps_needed __read_mostly;
3032

3033 3034 3035 3036
static struct rps_dev_flow *
set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
	    struct rps_dev_flow *rflow, u16 next_cpu)
{
3037
	if (next_cpu != RPS_NO_CPU) {
3038 3039 3040 3041 3042 3043 3044 3045 3046
#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? */
3047 3048
		if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
		    !(dev->features & NETIF_F_NTUPLE))
3049 3050 3051 3052 3053 3054 3055 3056 3057
			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;
3058
		flow_id = skb_get_hash(skb) & flow_table->mask;
3059 3060 3061 3062 3063 3064 3065 3066 3067 3068 3069 3070
		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->filter = rc;
		if (old_rflow->filter == rflow->filter)
			old_rflow->filter = RPS_NO_FILTER;
	out:
#endif
		rflow->last_qtail =
3071
			per_cpu(softnet_data, next_cpu).input_queue_head;
3072 3073
	}

3074
	rflow->cpu = next_cpu;
3075 3076 3077
	return rflow;
}

3078 3079 3080 3081 3082 3083 3084 3085
/*
 * 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)
{
3086 3087
	const struct rps_sock_flow_table *sock_flow_table;
	struct netdev_rx_queue *rxqueue = dev->_rx;
3088
	struct rps_dev_flow_table *flow_table;
3089
	struct rps_map *map;
3090
	int cpu = -1;
3091
	u32 tcpu;
3092
	u32 hash;
3093 3094 3095

	if (skb_rx_queue_recorded(skb)) {
		u16 index = skb_get_rx_queue(skb);
3096

3097 3098 3099 3100 3101
		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);
3102 3103
			goto done;
		}
3104 3105
		rxqueue += index;
	}
3106

3107 3108 3109
	/* Avoid computing hash if RFS/RPS is not active for this rxqueue */

	flow_table = rcu_dereference(rxqueue->rps_flow_table);
E
Eric Dumazet 已提交
3110
	map = rcu_dereference(rxqueue->rps_map);
3111
	if (!flow_table && !map)
3112 3113
		goto done;

3114
	skb_reset_network_header(skb);
3115 3116
	hash = skb_get_hash(skb);
	if (!hash)
3117 3118
		goto done;

T
Tom Herbert 已提交
3119 3120 3121
	sock_flow_table = rcu_dereference(rps_sock_flow_table);
	if (flow_table && sock_flow_table) {
		struct rps_dev_flow *rflow;
3122 3123 3124 3125 3126 3127 3128
		u32 next_cpu;
		u32 ident;

		/* First check into global flow table if there is a match */
		ident = sock_flow_table->ents[hash & sock_flow_table->mask];
		if ((ident ^ hash) & ~rps_cpu_mask)
			goto try_rps;
T
Tom Herbert 已提交
3129

3130 3131 3132 3133 3134
		next_cpu = ident & rps_cpu_mask;

		/* OK, now we know there is a match,
		 * we can look at the local (per receive queue) flow table
		 */
3135
		rflow = &flow_table->flows[hash & flow_table->mask];
T
Tom Herbert 已提交
3136 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151
		tcpu = rflow->cpu;

		/*
		 * 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 -
3152 3153
		      rflow->last_qtail)) >= 0)) {
			tcpu = next_cpu;
3154
			rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3155
		}
3156

T
Tom Herbert 已提交
3157 3158 3159 3160 3161 3162 3163
		if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
			*rflowp = rflow;
			cpu = tcpu;
			goto done;
		}
	}

3164 3165
try_rps:

T
Tom Herbert 已提交
3166
	if (map) {
3167
		tcpu = map->cpus[reciprocal_scale(hash, map->len)];
T
Tom Herbert 已提交
3168 3169 3170 3171 3172 3173 3174 3175 3176 3177
		if (cpu_online(tcpu)) {
			cpu = tcpu;
			goto done;
		}
	}

done:
	return cpu;
}

3178 3179 3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217
#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
3218
/* Called from hardirq (IPI) context */
E
Eric Dumazet 已提交
3219
static void rps_trigger_softirq(void *data)
T
Tom Herbert 已提交
3220
{
E
Eric Dumazet 已提交
3221 3222
	struct softnet_data *sd = data;

E
Eric Dumazet 已提交
3223
	____napi_schedule(sd, &sd->backlog);
C
Changli Gao 已提交
3224
	sd->received_rps++;
T
Tom Herbert 已提交
3225
}
E
Eric Dumazet 已提交
3226

T
Tom Herbert 已提交
3227
#endif /* CONFIG_RPS */
T
Tom Herbert 已提交
3228

E
Eric Dumazet 已提交
3229 3230 3231 3232 3233 3234 3235 3236
/*
 * 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
3237
	struct softnet_data *mysd = this_cpu_ptr(&softnet_data);
E
Eric Dumazet 已提交
3238 3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249

	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;
}

3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261 3262 3263
#ifdef CONFIG_NET_FLOW_LIMIT
int netdev_flow_limit_table_len __read_mostly = (1 << 12);
#endif

static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
{
#ifdef CONFIG_NET_FLOW_LIMIT
	struct sd_flow_limit *fl;
	struct softnet_data *sd;
	unsigned int old_flow, new_flow;

	if (qlen < (netdev_max_backlog >> 1))
		return false;

3264
	sd = this_cpu_ptr(&softnet_data);
3265 3266 3267 3268

	rcu_read_lock();
	fl = rcu_dereference(sd->flow_limit);
	if (fl) {
3269
		new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289
		old_flow = fl->history[fl->history_head];
		fl->history[fl->history_head] = new_flow;

		fl->history_head++;
		fl->history_head &= FLOW_LIMIT_HISTORY - 1;

		if (likely(fl->buckets[old_flow]))
			fl->buckets[old_flow]--;

		if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
			fl->count++;
			rcu_read_unlock();
			return true;
		}
	}
	rcu_read_unlock();
#endif
	return false;
}

T
Tom Herbert 已提交
3290 3291 3292 3293
/*
 * 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
3294 3295
static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
			      unsigned int *qtail)
T
Tom Herbert 已提交
3296
{
E
Eric Dumazet 已提交
3297
	struct softnet_data *sd;
T
Tom Herbert 已提交
3298
	unsigned long flags;
3299
	unsigned int qlen;
T
Tom Herbert 已提交
3300

E
Eric Dumazet 已提交
3301
	sd = &per_cpu(softnet_data, cpu);
T
Tom Herbert 已提交
3302 3303 3304

	local_irq_save(flags);

E
Eric Dumazet 已提交
3305
	rps_lock(sd);
3306 3307
	qlen = skb_queue_len(&sd->input_pkt_queue);
	if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3308
		if (qlen) {
T
Tom Herbert 已提交
3309
enqueue:
E
Eric Dumazet 已提交
3310
			__skb_queue_tail(&sd->input_pkt_queue, skb);
3311
			input_queue_tail_incr_save(sd, qtail);
E
Eric Dumazet 已提交
3312
			rps_unlock(sd);
3313
			local_irq_restore(flags);
T
Tom Herbert 已提交
3314 3315 3316
			return NET_RX_SUCCESS;
		}

3317 3318 3319 3320
		/* 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
3321
			if (!rps_ipi_queued(sd))
E
Eric Dumazet 已提交
3322
				____napi_schedule(sd, &sd->backlog);
T
Tom Herbert 已提交
3323 3324 3325 3326
		}
		goto enqueue;
	}

C
Changli Gao 已提交
3327
	sd->dropped++;
E
Eric Dumazet 已提交
3328
	rps_unlock(sd);
T
Tom Herbert 已提交
3329 3330 3331

	local_irq_restore(flags);

3332
	atomic_long_inc(&skb->dev->rx_dropped);
T
Tom Herbert 已提交
3333 3334 3335
	kfree_skb(skb);
	return NET_RX_DROP;
}
L
Linus Torvalds 已提交
3336

3337
static int netif_rx_internal(struct sk_buff *skb)
L
Linus Torvalds 已提交
3338
{
3339
	int ret;
L
Linus Torvalds 已提交
3340

3341
	net_timestamp_check(netdev_tstamp_prequeue, skb);
L
Linus Torvalds 已提交
3342

3343
	trace_netif_rx(skb);
E
Eric Dumazet 已提交
3344
#ifdef CONFIG_RPS
3345
	if (static_key_false(&rps_needed)) {
T
Tom Herbert 已提交
3346
		struct rps_dev_flow voidflow, *rflow = &voidflow;
3347 3348
		int cpu;

3349
		preempt_disable();
3350
		rcu_read_lock();
T
Tom Herbert 已提交
3351 3352

		cpu = get_rps_cpu(skb->dev, skb, &rflow);
3353 3354
		if (cpu < 0)
			cpu = smp_processor_id();
T
Tom Herbert 已提交
3355 3356 3357

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

3358
		rcu_read_unlock();
3359
		preempt_enable();
3360 3361
	} else
#endif
T
Tom Herbert 已提交
3362 3363 3364 3365 3366
	{
		unsigned int qtail;
		ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
		put_cpu();
	}
3367
	return ret;
L
Linus Torvalds 已提交
3368
}
3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390

/**
 *	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)
{
	trace_netif_rx_entry(skb);

	return netif_rx_internal(skb);
}
E
Eric Dumazet 已提交
3391
EXPORT_SYMBOL(netif_rx);
L
Linus Torvalds 已提交
3392 3393 3394 3395 3396

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

3397 3398
	trace_netif_rx_ni_entry(skb);

L
Linus Torvalds 已提交
3399
	preempt_disable();
3400
	err = netif_rx_internal(skb);
L
Linus Torvalds 已提交
3401 3402 3403 3404 3405 3406 3407 3408 3409 3410
	if (local_softirq_pending())
		do_softirq();
	preempt_enable();

	return err;
}
EXPORT_SYMBOL(netif_rx_ni);

static void net_tx_action(struct softirq_action *h)
{
3411
	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
L
Linus Torvalds 已提交
3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424

	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;

3425
			WARN_ON(atomic_read(&skb->users));
3426 3427 3428 3429
			if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
				trace_consume_skb(skb);
			else
				trace_kfree_skb(skb, net_tx_action);
L
Linus Torvalds 已提交
3430 3431 3432 3433 3434
			__kfree_skb(skb);
		}
	}

	if (sd->output_queue) {
3435
		struct Qdisc *head;
L
Linus Torvalds 已提交
3436 3437 3438 3439

		local_irq_disable();
		head = sd->output_queue;
		sd->output_queue = NULL;
3440
		sd->output_queue_tailp = &sd->output_queue;
L
Linus Torvalds 已提交
3441 3442 3443
		local_irq_enable();

		while (head) {
3444 3445 3446
			struct Qdisc *q = head;
			spinlock_t *root_lock;

L
Linus Torvalds 已提交
3447 3448
			head = head->next_sched;

3449
			root_lock = qdisc_lock(q);
3450
			if (spin_trylock(root_lock)) {
3451
				smp_mb__before_atomic();
3452 3453
				clear_bit(__QDISC_STATE_SCHED,
					  &q->state);
3454 3455
				qdisc_run(q);
				spin_unlock(root_lock);
L
Linus Torvalds 已提交
3456
			} else {
3457
				if (!test_bit(__QDISC_STATE_DEACTIVATED,
3458
					      &q->state)) {
3459
					__netif_reschedule(q);
3460
				} else {
3461
					smp_mb__before_atomic();
3462 3463 3464
					clear_bit(__QDISC_STATE_SCHED,
						  &q->state);
				}
L
Linus Torvalds 已提交
3465 3466 3467 3468 3469
			}
		}
	}
}

3470 3471
#if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
    (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
3472 3473 3474
/* This hook is defined here for ATM LANE */
int (*br_fdb_test_addr_hook)(struct net_device *dev,
			     unsigned char *addr) __read_mostly;
3475
EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3476
#endif
L
Linus Torvalds 已提交
3477 3478 3479 3480 3481 3482

#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
3483 3484
 * 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
3485 3486
 *
 */
3487
static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
L
Linus Torvalds 已提交
3488 3489
{
	struct net_device *dev = skb->dev;
3490
	u32 ttl = G_TC_RTTL(skb->tc_verd);
3491 3492
	int result = TC_ACT_OK;
	struct Qdisc *q;
3493

3494
	if (unlikely(MAX_RED_LOOP < ttl++)) {
3495 3496
		net_warn_ratelimited("Redir loop detected Dropping packet (%d->%d)\n",
				     skb->skb_iif, dev->ifindex);
3497 3498
		return TC_ACT_SHOT;
	}
L
Linus Torvalds 已提交
3499

3500 3501
	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
3502

3503
	q = rcu_dereference(rxq->qdisc);
3504
	if (q != &noop_qdisc) {
3505
		spin_lock(qdisc_lock(q));
3506 3507
		if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
			result = qdisc_enqueue_root(skb, q);
3508 3509
		spin_unlock(qdisc_lock(q));
	}
3510 3511 3512

	return result;
}
3513

3514 3515 3516 3517
static inline struct sk_buff *handle_ing(struct sk_buff *skb,
					 struct packet_type **pt_prev,
					 int *ret, struct net_device *orig_dev)
{
3518 3519
	struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);

3520
	if (!rxq || rcu_access_pointer(rxq->qdisc) == &noop_qdisc)
3521
		goto out;
L
Linus Torvalds 已提交
3522

3523 3524 3525
	if (*pt_prev) {
		*ret = deliver_skb(skb, *pt_prev, orig_dev);
		*pt_prev = NULL;
L
Linus Torvalds 已提交
3526 3527
	}

3528
	switch (ing_filter(skb, rxq)) {
3529 3530 3531 3532 3533 3534 3535 3536 3537
	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
3538 3539 3540
}
#endif

3541 3542 3543 3544
/**
 *	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
3545
 *	@rx_handler_data: data pointer that is used by rx handler
3546
 *
3547
 *	Register a receive handler for a device. This handler will then be
3548 3549 3550 3551
 *	called from __netif_receive_skb. A negative errno code is returned
 *	on a failure.
 *
 *	The caller must hold the rtnl_mutex.
3552 3553
 *
 *	For a general description of rx_handler, see enum rx_handler_result.
3554 3555
 */
int netdev_rx_handler_register(struct net_device *dev,
J
Jiri Pirko 已提交
3556 3557
			       rx_handler_func_t *rx_handler,
			       void *rx_handler_data)
3558 3559 3560 3561 3562 3563
{
	ASSERT_RTNL();

	if (dev->rx_handler)
		return -EBUSY;

3564
	/* Note: rx_handler_data must be set before rx_handler */
J
Jiri Pirko 已提交
3565
	rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3566 3567 3568 3569 3570 3571 3572 3573 3574 3575
	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
 *
K
Kusanagi Kouichi 已提交
3576
 *	Unregister a receive handler from a device.
3577 3578 3579 3580 3581 3582 3583
 *
 *	The caller must hold the rtnl_mutex.
 */
void netdev_rx_handler_unregister(struct net_device *dev)
{

	ASSERT_RTNL();
3584
	RCU_INIT_POINTER(dev->rx_handler, NULL);
3585 3586 3587 3588 3589
	/* a reader seeing a non NULL rx_handler in a rcu_read_lock()
	 * section has a guarantee to see a non NULL rx_handler_data
	 * as well.
	 */
	synchronize_net();
3590
	RCU_INIT_POINTER(dev->rx_handler_data, NULL);
3591 3592 3593
}
EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);

3594 3595 3596 3597 3598 3599 3600
/*
 * Limit the use of PFMEMALLOC reserves to those protocols that implement
 * the special handling of PFMEMALLOC skbs.
 */
static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
{
	switch (skb->protocol) {
3601 3602 3603 3604 3605
	case htons(ETH_P_ARP):
	case htons(ETH_P_IP):
	case htons(ETH_P_IPV6):
	case htons(ETH_P_8021Q):
	case htons(ETH_P_8021AD):
3606 3607 3608 3609 3610 3611
		return true;
	default:
		return false;
	}
}

3612
static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
L
Linus Torvalds 已提交
3613 3614
{
	struct packet_type *ptype, *pt_prev;
3615
	rx_handler_func_t *rx_handler;
D
David S. Miller 已提交
3616
	struct net_device *orig_dev;
3617
	bool deliver_exact = false;
L
Linus Torvalds 已提交
3618
	int ret = NET_RX_DROP;
A
Al Viro 已提交
3619
	__be16 type;
L
Linus Torvalds 已提交
3620

3621
	net_timestamp_check(!netdev_tstamp_prequeue, skb);
3622

3623
	trace_netif_receive_skb(skb);
3624

J
Joe Eykholt 已提交
3625
	orig_dev = skb->dev;
3626

3627
	skb_reset_network_header(skb);
3628 3629
	if (!skb_transport_header_was_set(skb))
		skb_reset_transport_header(skb);
3630
	skb_reset_mac_len(skb);
L
Linus Torvalds 已提交
3631 3632 3633 3634 3635

	pt_prev = NULL;

	rcu_read_lock();

3636
another_round:
3637
	skb->skb_iif = skb->dev->ifindex;
3638 3639 3640

	__this_cpu_inc(softnet_data.processed);

P
Patrick McHardy 已提交
3641 3642
	if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
	    skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
3643
		skb = skb_vlan_untag(skb);
3644
		if (unlikely(!skb))
3645
			goto unlock;
3646 3647
	}

L
Linus Torvalds 已提交
3648 3649 3650 3651 3652 3653 3654
#ifdef CONFIG_NET_CLS_ACT
	if (skb->tc_verd & TC_NCLS) {
		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
		goto ncls;
	}
#endif

3655
	if (pfmemalloc)
3656 3657
		goto skip_taps;

L
Linus Torvalds 已提交
3658
	list_for_each_entry_rcu(ptype, &ptype_all, list) {
3659 3660 3661 3662 3663 3664 3665 3666 3667
		if (pt_prev)
			ret = deliver_skb(skb, pt_prev, orig_dev);
		pt_prev = ptype;
	}

	list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) {
		if (pt_prev)
			ret = deliver_skb(skb, pt_prev, orig_dev);
		pt_prev = ptype;
L
Linus Torvalds 已提交
3668 3669
	}

3670
skip_taps:
L
Linus Torvalds 已提交
3671
#ifdef CONFIG_NET_CLS_ACT
3672 3673
	skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
	if (!skb)
3674
		goto unlock;
L
Linus Torvalds 已提交
3675 3676 3677
ncls:
#endif

3678
	if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
3679 3680
		goto drop;

3681
	if (skb_vlan_tag_present(skb)) {
3682 3683 3684 3685
		if (pt_prev) {
			ret = deliver_skb(skb, pt_prev, orig_dev);
			pt_prev = NULL;
		}
3686
		if (vlan_do_receive(&skb))
3687 3688
			goto another_round;
		else if (unlikely(!skb))
3689
			goto unlock;
3690 3691
	}

3692
	rx_handler = rcu_dereference(skb->dev->rx_handler);
3693 3694 3695 3696 3697
	if (rx_handler) {
		if (pt_prev) {
			ret = deliver_skb(skb, pt_prev, orig_dev);
			pt_prev = NULL;
		}
3698 3699
		switch (rx_handler(&skb)) {
		case RX_HANDLER_CONSUMED:
3700
			ret = NET_RX_SUCCESS;
3701
			goto unlock;
3702
		case RX_HANDLER_ANOTHER:
3703
			goto another_round;
3704 3705 3706 3707 3708 3709 3710
		case RX_HANDLER_EXACT:
			deliver_exact = true;
		case RX_HANDLER_PASS:
			break;
		default:
			BUG();
		}
3711
	}
L
Linus Torvalds 已提交
3712

3713 3714
	if (unlikely(skb_vlan_tag_present(skb))) {
		if (skb_vlan_tag_get_id(skb))
E
Eric Dumazet 已提交
3715 3716 3717 3718 3719 3720 3721
			skb->pkt_type = PACKET_OTHERHOST;
		/* Note: we might in the future use prio bits
		 * and set skb->priority like in vlan_do_receive()
		 * For the time being, just ignore Priority Code Point
		 */
		skb->vlan_tci = 0;
	}
3722

3723 3724
	type = skb->protocol;

3725
	/* deliver only exact match when indicated */
3726 3727 3728 3729 3730
	if (likely(!deliver_exact)) {
		deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
				       &ptype_base[ntohs(type) &
						   PTYPE_HASH_MASK]);
	}
3731

3732 3733 3734 3735 3736 3737
	deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
			       &orig_dev->ptype_specific);

	if (unlikely(skb->dev != orig_dev)) {
		deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
				       &skb->dev->ptype_specific);
L
Linus Torvalds 已提交
3738 3739 3740
	}

	if (pt_prev) {
3741
		if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
3742
			goto drop;
3743 3744
		else
			ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
L
Linus Torvalds 已提交
3745
	} else {
3746
drop:
3747
		atomic_long_inc(&skb->dev->rx_dropped);
L
Linus Torvalds 已提交
3748 3749 3750 3751 3752 3753 3754
		kfree_skb(skb);
		/* Jamal, now you will not able to escape explaining
		 * me how you were going to use this. :-)
		 */
		ret = NET_RX_DROP;
	}

3755
unlock:
L
Linus Torvalds 已提交
3756
	rcu_read_unlock();
3757 3758 3759 3760 3761 3762 3763 3764 3765 3766 3767 3768 3769 3770 3771 3772 3773 3774 3775 3776 3777 3778 3779 3780 3781
	return ret;
}

static int __netif_receive_skb(struct sk_buff *skb)
{
	int ret;

	if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
		unsigned long pflags = current->flags;

		/*
		 * PFMEMALLOC skbs are special, they should
		 * - be delivered to SOCK_MEMALLOC sockets only
		 * - stay away from userspace
		 * - have bounded memory usage
		 *
		 * Use PF_MEMALLOC as this saves us from propagating the allocation
		 * context down to all allocation sites.
		 */
		current->flags |= PF_MEMALLOC;
		ret = __netif_receive_skb_core(skb, true);
		tsk_restore_flags(current, pflags, PF_MEMALLOC);
	} else
		ret = __netif_receive_skb_core(skb, false);

L
Linus Torvalds 已提交
3782 3783
	return ret;
}
T
Tom Herbert 已提交
3784

3785
static int netif_receive_skb_internal(struct sk_buff *skb)
T
Tom Herbert 已提交
3786
{
3787
	net_timestamp_check(netdev_tstamp_prequeue, skb);
E
Eric Dumazet 已提交
3788

3789 3790 3791
	if (skb_defer_rx_timestamp(skb))
		return NET_RX_SUCCESS;

E
Eric Dumazet 已提交
3792
#ifdef CONFIG_RPS
3793
	if (static_key_false(&rps_needed)) {
E
Eric Dumazet 已提交
3794 3795
		struct rps_dev_flow voidflow, *rflow = &voidflow;
		int cpu, ret;
T
Tom Herbert 已提交
3796

E
Eric Dumazet 已提交
3797 3798 3799
		rcu_read_lock();

		cpu = get_rps_cpu(skb->dev, skb, &rflow);
T
Tom Herbert 已提交
3800

E
Eric Dumazet 已提交
3801 3802 3803
		if (cpu >= 0) {
			ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
			rcu_read_unlock();
3804
			return ret;
E
Eric Dumazet 已提交
3805
		}
3806
		rcu_read_unlock();
T
Tom Herbert 已提交
3807
	}
3808
#endif
3809
	return __netif_receive_skb(skb);
T
Tom Herbert 已提交
3810
}
3811 3812 3813 3814 3815 3816 3817 3818 3819 3820 3821 3822 3823 3824 3825 3826 3827 3828 3829 3830 3831 3832

/**
 *	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)
{
	trace_netif_receive_skb_entry(skb);

	return netif_receive_skb_internal(skb);
}
E
Eric Dumazet 已提交
3833
EXPORT_SYMBOL(netif_receive_skb);
L
Linus Torvalds 已提交
3834

E
Eric Dumazet 已提交
3835 3836 3837
/* Network device is going away, flush any packets still pending
 * Called with irqs disabled.
 */
3838
static void flush_backlog(void *arg)
3839
{
3840
	struct net_device *dev = arg;
3841
	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
3842 3843
	struct sk_buff *skb, *tmp;

E
Eric Dumazet 已提交
3844
	rps_lock(sd);
3845
	skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3846
		if (skb->dev == dev) {
E
Eric Dumazet 已提交
3847
			__skb_unlink(skb, &sd->input_pkt_queue);
3848
			kfree_skb(skb);
3849
			input_queue_head_incr(sd);
3850
		}
3851
	}
E
Eric Dumazet 已提交
3852
	rps_unlock(sd);
3853 3854 3855 3856 3857

	skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
		if (skb->dev == dev) {
			__skb_unlink(skb, &sd->process_queue);
			kfree_skb(skb);
3858
			input_queue_head_incr(sd);
3859 3860
		}
	}
3861 3862
}

3863 3864
static int napi_gro_complete(struct sk_buff *skb)
{
3865
	struct packet_offload *ptype;
3866
	__be16 type = skb->protocol;
3867
	struct list_head *head = &offload_base;
3868 3869
	int err = -ENOENT;

3870 3871
	BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));

3872 3873
	if (NAPI_GRO_CB(skb)->count == 1) {
		skb_shinfo(skb)->gso_size = 0;
3874
		goto out;
3875
	}
3876 3877 3878

	rcu_read_lock();
	list_for_each_entry_rcu(ptype, head, list) {
3879
		if (ptype->type != type || !ptype->callbacks.gro_complete)
3880 3881
			continue;

3882
		err = ptype->callbacks.gro_complete(skb, 0);
3883 3884 3885 3886 3887 3888 3889 3890 3891 3892 3893
		break;
	}
	rcu_read_unlock();

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

out:
3894
	return netif_receive_skb_internal(skb);
3895 3896
}

3897 3898 3899 3900 3901
/* napi->gro_list contains packets ordered by age.
 * youngest packets at the head of it.
 * Complete skbs in reverse order to reduce latencies.
 */
void napi_gro_flush(struct napi_struct *napi, bool flush_old)
3902
{
3903
	struct sk_buff *skb, *prev = NULL;
3904

3905 3906 3907 3908 3909 3910 3911
	/* scan list and build reverse chain */
	for (skb = napi->gro_list; skb != NULL; skb = skb->next) {
		skb->prev = prev;
		prev = skb;
	}

	for (skb = prev; skb; skb = prev) {
3912
		skb->next = NULL;
3913 3914 3915 3916 3917

		if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
			return;

		prev = skb->prev;
3918
		napi_gro_complete(skb);
3919
		napi->gro_count--;
3920 3921 3922 3923
	}

	napi->gro_list = NULL;
}
E
Eric Dumazet 已提交
3924
EXPORT_SYMBOL(napi_gro_flush);
3925

E
Eric Dumazet 已提交
3926 3927 3928 3929
static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb)
{
	struct sk_buff *p;
	unsigned int maclen = skb->dev->hard_header_len;
3930
	u32 hash = skb_get_hash_raw(skb);
E
Eric Dumazet 已提交
3931 3932 3933 3934

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

3935 3936 3937 3938 3939 3940 3941
		NAPI_GRO_CB(p)->flush = 0;

		if (hash != skb_get_hash_raw(p)) {
			NAPI_GRO_CB(p)->same_flow = 0;
			continue;
		}

E
Eric Dumazet 已提交
3942 3943 3944 3945
		diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
		diffs |= p->vlan_tci ^ skb->vlan_tci;
		if (maclen == ETH_HLEN)
			diffs |= compare_ether_header(skb_mac_header(p),
3946
						      skb_mac_header(skb));
E
Eric Dumazet 已提交
3947 3948
		else if (!diffs)
			diffs = memcmp(skb_mac_header(p),
3949
				       skb_mac_header(skb),
E
Eric Dumazet 已提交
3950 3951 3952 3953 3954
				       maclen);
		NAPI_GRO_CB(p)->same_flow = !diffs;
	}
}

3955 3956 3957 3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968
static void skb_gro_reset_offset(struct sk_buff *skb)
{
	const struct skb_shared_info *pinfo = skb_shinfo(skb);
	const skb_frag_t *frag0 = &pinfo->frags[0];

	NAPI_GRO_CB(skb)->data_offset = 0;
	NAPI_GRO_CB(skb)->frag0 = NULL;
	NAPI_GRO_CB(skb)->frag0_len = 0;

	if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
	    pinfo->nr_frags &&
	    !PageHighMem(skb_frag_page(frag0))) {
		NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
		NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(frag0);
E
Eric Dumazet 已提交
3969 3970 3971
	}
}

3972 3973 3974 3975 3976 3977 3978 3979 3980 3981 3982 3983 3984 3985 3986 3987 3988 3989 3990 3991 3992
static void gro_pull_from_frag0(struct sk_buff *skb, int grow)
{
	struct skb_shared_info *pinfo = skb_shinfo(skb);

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

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

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

	pinfo->frags[0].page_offset += grow;
	skb_frag_size_sub(&pinfo->frags[0], grow);

	if (unlikely(!skb_frag_size(&pinfo->frags[0]))) {
		skb_frag_unref(skb, 0);
		memmove(pinfo->frags, pinfo->frags + 1,
			--pinfo->nr_frags * sizeof(pinfo->frags[0]));
	}
}

R
Rami Rosen 已提交
3993
static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
3994 3995
{
	struct sk_buff **pp = NULL;
3996
	struct packet_offload *ptype;
3997
	__be16 type = skb->protocol;
3998
	struct list_head *head = &offload_base;
H
Herbert Xu 已提交
3999
	int same_flow;
4000
	enum gro_result ret;
4001
	int grow;
4002

4003
	if (!(skb->dev->features & NETIF_F_GRO))
4004 4005
		goto normal;

4006
	if (skb_is_gso(skb) || skb_has_frag_list(skb) || skb->csum_bad)
4007 4008
		goto normal;

E
Eric Dumazet 已提交
4009 4010
	gro_list_prepare(napi, skb);

4011 4012
	rcu_read_lock();
	list_for_each_entry_rcu(ptype, head, list) {
4013
		if (ptype->type != type || !ptype->callbacks.gro_receive)
4014 4015
			continue;

4016
		skb_set_network_header(skb, skb_gro_offset(skb));
4017
		skb_reset_mac_len(skb);
4018 4019
		NAPI_GRO_CB(skb)->same_flow = 0;
		NAPI_GRO_CB(skb)->flush = 0;
H
Herbert Xu 已提交
4020
		NAPI_GRO_CB(skb)->free = 0;
4021
		NAPI_GRO_CB(skb)->udp_mark = 0;
4022
		NAPI_GRO_CB(skb)->gro_remcsum_start = 0;
4023

4024 4025 4026 4027 4028 4029 4030 4031 4032 4033 4034 4035 4036 4037 4038
		/* Setup for GRO checksum validation */
		switch (skb->ip_summed) {
		case CHECKSUM_COMPLETE:
			NAPI_GRO_CB(skb)->csum = skb->csum;
			NAPI_GRO_CB(skb)->csum_valid = 1;
			NAPI_GRO_CB(skb)->csum_cnt = 0;
			break;
		case CHECKSUM_UNNECESSARY:
			NAPI_GRO_CB(skb)->csum_cnt = skb->csum_level + 1;
			NAPI_GRO_CB(skb)->csum_valid = 0;
			break;
		default:
			NAPI_GRO_CB(skb)->csum_cnt = 0;
			NAPI_GRO_CB(skb)->csum_valid = 0;
		}
4039

4040
		pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
4041 4042 4043 4044 4045 4046 4047
		break;
	}
	rcu_read_unlock();

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

H
Herbert Xu 已提交
4048
	same_flow = NAPI_GRO_CB(skb)->same_flow;
4049
	ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
H
Herbert Xu 已提交
4050

4051 4052 4053 4054 4055 4056
	if (pp) {
		struct sk_buff *nskb = *pp;

		*pp = nskb->next;
		nskb->next = NULL;
		napi_gro_complete(nskb);
4057
		napi->gro_count--;
4058 4059
	}

H
Herbert Xu 已提交
4060
	if (same_flow)
4061 4062
		goto ok;

4063
	if (NAPI_GRO_CB(skb)->flush)
4064 4065
		goto normal;

4066 4067 4068 4069 4070 4071 4072 4073 4074 4075 4076 4077 4078 4079
	if (unlikely(napi->gro_count >= MAX_GRO_SKBS)) {
		struct sk_buff *nskb = napi->gro_list;

		/* locate the end of the list to select the 'oldest' flow */
		while (nskb->next) {
			pp = &nskb->next;
			nskb = *pp;
		}
		*pp = NULL;
		nskb->next = NULL;
		napi_gro_complete(nskb);
	} else {
		napi->gro_count++;
	}
4080
	NAPI_GRO_CB(skb)->count = 1;
4081
	NAPI_GRO_CB(skb)->age = jiffies;
4082
	NAPI_GRO_CB(skb)->last = skb;
4083
	skb_shinfo(skb)->gso_size = skb_gro_len(skb);
4084 4085
	skb->next = napi->gro_list;
	napi->gro_list = skb;
4086
	ret = GRO_HELD;
4087

4088
pull:
4089 4090 4091
	grow = skb_gro_offset(skb) - skb_headlen(skb);
	if (grow > 0)
		gro_pull_from_frag0(skb, grow);
4092
ok:
4093
	return ret;
4094 4095

normal:
4096 4097
	ret = GRO_NORMAL;
	goto pull;
H
Herbert Xu 已提交
4098
}
4099

4100 4101 4102 4103 4104 4105 4106 4107 4108 4109 4110 4111
struct packet_offload *gro_find_receive_by_type(__be16 type)
{
	struct list_head *offload_head = &offload_base;
	struct packet_offload *ptype;

	list_for_each_entry_rcu(ptype, offload_head, list) {
		if (ptype->type != type || !ptype->callbacks.gro_receive)
			continue;
		return ptype;
	}
	return NULL;
}
4112
EXPORT_SYMBOL(gro_find_receive_by_type);
4113 4114 4115 4116 4117 4118 4119 4120 4121 4122 4123 4124 4125

struct packet_offload *gro_find_complete_by_type(__be16 type)
{
	struct list_head *offload_head = &offload_base;
	struct packet_offload *ptype;

	list_for_each_entry_rcu(ptype, offload_head, list) {
		if (ptype->type != type || !ptype->callbacks.gro_complete)
			continue;
		return ptype;
	}
	return NULL;
}
4126
EXPORT_SYMBOL(gro_find_complete_by_type);
H
Herbert Xu 已提交
4127

R
Rami Rosen 已提交
4128
static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
H
Herbert Xu 已提交
4129
{
4130 4131
	switch (ret) {
	case GRO_NORMAL:
4132
		if (netif_receive_skb_internal(skb))
4133 4134
			ret = GRO_DROP;
		break;
H
Herbert Xu 已提交
4135

4136
	case GRO_DROP:
H
Herbert Xu 已提交
4137 4138
		kfree_skb(skb);
		break;
4139

4140
	case GRO_MERGED_FREE:
4141 4142 4143 4144
		if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
			kmem_cache_free(skbuff_head_cache, skb);
		else
			__kfree_skb(skb);
4145 4146
		break;

4147 4148 4149
	case GRO_HELD:
	case GRO_MERGED:
		break;
H
Herbert Xu 已提交
4150 4151
	}

4152
	return ret;
4153 4154
}

4155
gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4156
{
4157
	trace_napi_gro_receive_entry(skb);
4158

4159 4160
	skb_gro_reset_offset(skb);

E
Eric Dumazet 已提交
4161
	return napi_skb_finish(dev_gro_receive(napi, skb), skb);
4162 4163 4164
}
EXPORT_SYMBOL(napi_gro_receive);

S
stephen hemminger 已提交
4165
static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
4166
{
4167 4168 4169 4170
	if (unlikely(skb->pfmemalloc)) {
		consume_skb(skb);
		return;
	}
4171
	__skb_pull(skb, skb_headlen(skb));
4172 4173
	/* restore the reserve we had after netdev_alloc_skb_ip_align() */
	skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
4174
	skb->vlan_tci = 0;
H
Herbert Xu 已提交
4175
	skb->dev = napi->dev;
A
Andy Gospodarek 已提交
4176
	skb->skb_iif = 0;
4177 4178
	skb->encapsulation = 0;
	skb_shinfo(skb)->gso_type = 0;
4179
	skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
4180 4181 4182 4183

	napi->skb = skb;
}

4184
struct sk_buff *napi_get_frags(struct napi_struct *napi)
H
Herbert Xu 已提交
4185 4186 4187 4188
{
	struct sk_buff *skb = napi->skb;

	if (!skb) {
4189
		skb = napi_alloc_skb(napi, GRO_MAX_HEAD);
E
Eric Dumazet 已提交
4190
		napi->skb = skb;
4191
	}
4192 4193
	return skb;
}
4194
EXPORT_SYMBOL(napi_get_frags);
4195

4196 4197 4198
static gro_result_t napi_frags_finish(struct napi_struct *napi,
				      struct sk_buff *skb,
				      gro_result_t ret)
4199
{
4200 4201
	switch (ret) {
	case GRO_NORMAL:
4202 4203 4204 4205
	case GRO_HELD:
		__skb_push(skb, ETH_HLEN);
		skb->protocol = eth_type_trans(skb, skb->dev);
		if (ret == GRO_NORMAL && netif_receive_skb_internal(skb))
4206
			ret = GRO_DROP;
4207
		break;
H
Herbert Xu 已提交
4208

4209 4210 4211 4212
	case GRO_DROP:
	case GRO_MERGED_FREE:
		napi_reuse_skb(napi, skb);
		break;
4213 4214 4215

	case GRO_MERGED:
		break;
4216
	}
H
Herbert Xu 已提交
4217

4218
	return ret;
H
Herbert Xu 已提交
4219
}
4220

4221 4222 4223 4224
/* Upper GRO stack assumes network header starts at gro_offset=0
 * Drivers could call both napi_gro_frags() and napi_gro_receive()
 * We copy ethernet header into skb->data to have a common layout.
 */
E
Eric Dumazet 已提交
4225
static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4226 4227
{
	struct sk_buff *skb = napi->skb;
4228 4229
	const struct ethhdr *eth;
	unsigned int hlen = sizeof(*eth);
4230 4231 4232

	napi->skb = NULL;

4233 4234 4235 4236 4237 4238 4239 4240 4241 4242 4243 4244 4245 4246
	skb_reset_mac_header(skb);
	skb_gro_reset_offset(skb);

	eth = skb_gro_header_fast(skb, 0);
	if (unlikely(skb_gro_header_hard(skb, hlen))) {
		eth = skb_gro_header_slow(skb, hlen, 0);
		if (unlikely(!eth)) {
			napi_reuse_skb(napi, skb);
			return NULL;
		}
	} else {
		gro_pull_from_frag0(skb, hlen);
		NAPI_GRO_CB(skb)->frag0 += hlen;
		NAPI_GRO_CB(skb)->frag0_len -= hlen;
4247
	}
4248 4249 4250 4251 4252 4253 4254 4255
	__skb_pull(skb, hlen);

	/*
	 * This works because the only protocols we care about don't require
	 * special handling.
	 * We'll fix it up properly in napi_frags_finish()
	 */
	skb->protocol = eth->h_proto;
4256 4257 4258 4259

	return skb;
}

4260
gro_result_t napi_gro_frags(struct napi_struct *napi)
4261
{
4262
	struct sk_buff *skb = napi_frags_skb(napi);
4263 4264

	if (!skb)
4265
		return GRO_DROP;
4266

4267 4268
	trace_napi_gro_frags_entry(skb);

E
Eric Dumazet 已提交
4269
	return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4270
}
H
Herbert Xu 已提交
4271 4272
EXPORT_SYMBOL(napi_gro_frags);

T
Tom Herbert 已提交
4273 4274 4275 4276 4277 4278 4279 4280 4281 4282 4283 4284 4285 4286 4287 4288 4289 4290 4291 4292 4293 4294 4295 4296 4297
/* Compute the checksum from gro_offset and return the folded value
 * after adding in any pseudo checksum.
 */
__sum16 __skb_gro_checksum_complete(struct sk_buff *skb)
{
	__wsum wsum;
	__sum16 sum;

	wsum = skb_checksum(skb, skb_gro_offset(skb), skb_gro_len(skb), 0);

	/* NAPI_GRO_CB(skb)->csum holds pseudo checksum */
	sum = csum_fold(csum_add(NAPI_GRO_CB(skb)->csum, wsum));
	if (likely(!sum)) {
		if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) &&
		    !skb->csum_complete_sw)
			netdev_rx_csum_fault(skb->dev);
	}

	NAPI_GRO_CB(skb)->csum = wsum;
	NAPI_GRO_CB(skb)->csum_valid = 1;

	return sum;
}
EXPORT_SYMBOL(__skb_gro_checksum_complete);

4298
/*
4299
 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
4300 4301 4302 4303 4304 4305 4306 4307 4308 4309 4310 4311 4312 4313 4314 4315 4316
 * 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))
4317
				smp_call_function_single_async(remsd->cpu,
4318
							   &remsd->csd);
4319 4320 4321 4322 4323 4324 4325
			remsd = next;
		}
	} else
#endif
		local_irq_enable();
}

E
Eric Dumazet 已提交
4326 4327 4328 4329 4330 4331 4332 4333 4334
static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
{
#ifdef CONFIG_RPS
	return sd->rps_ipi_list != NULL;
#else
	return false;
#endif
}

4335
static int process_backlog(struct napi_struct *napi, int quota)
L
Linus Torvalds 已提交
4336 4337
{
	int work = 0;
E
Eric Dumazet 已提交
4338
	struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
L
Linus Torvalds 已提交
4339

4340 4341 4342
	/* Check if we have pending ipi, its better to send them now,
	 * not waiting net_rx_action() end.
	 */
E
Eric Dumazet 已提交
4343
	if (sd_has_rps_ipi_waiting(sd)) {
4344 4345 4346
		local_irq_disable();
		net_rps_action_and_irq_enable(sd);
	}
E
Eric Dumazet 已提交
4347

4348
	napi->weight = weight_p;
4349
	local_irq_disable();
4350
	while (1) {
L
Linus Torvalds 已提交
4351
		struct sk_buff *skb;
4352 4353 4354 4355 4356

		while ((skb = __skb_dequeue(&sd->process_queue))) {
			local_irq_enable();
			__netif_receive_skb(skb);
			local_irq_disable();
4357 4358 4359 4360 4361
			input_queue_head_incr(sd);
			if (++work >= quota) {
				local_irq_enable();
				return work;
			}
4362
		}
L
Linus Torvalds 已提交
4363

E
Eric Dumazet 已提交
4364
		rps_lock(sd);
4365
		if (skb_queue_empty(&sd->input_pkt_queue)) {
E
Eric Dumazet 已提交
4366 4367 4368
			/*
			 * Inline a custom version of __napi_complete().
			 * only current cpu owns and manipulates this napi,
4369 4370 4371
			 * and NAPI_STATE_SCHED is the only possible flag set
			 * on backlog.
			 * We can use a plain write instead of clear_bit(),
E
Eric Dumazet 已提交
4372 4373 4374
			 * and we dont need an smp_mb() memory barrier.
			 */
			napi->state = 0;
4375
			rps_unlock(sd);
E
Eric Dumazet 已提交
4376

4377
			break;
4378
		}
4379 4380 4381

		skb_queue_splice_tail_init(&sd->input_pkt_queue,
					   &sd->process_queue);
E
Eric Dumazet 已提交
4382
		rps_unlock(sd);
4383 4384
	}
	local_irq_enable();
L
Linus Torvalds 已提交
4385

4386 4387
	return work;
}
L
Linus Torvalds 已提交
4388

4389 4390
/**
 * __napi_schedule - schedule for receive
4391
 * @n: entry to schedule
4392
 *
4393 4394
 * The entry's receive function will be scheduled to run.
 * Consider using __napi_schedule_irqoff() if hard irqs are masked.
4395
 */
H
Harvey Harrison 已提交
4396
void __napi_schedule(struct napi_struct *n)
4397 4398
{
	unsigned long flags;
L
Linus Torvalds 已提交
4399

4400
	local_irq_save(flags);
4401
	____napi_schedule(this_cpu_ptr(&softnet_data), n);
4402
	local_irq_restore(flags);
L
Linus Torvalds 已提交
4403
}
4404 4405
EXPORT_SYMBOL(__napi_schedule);

4406 4407 4408 4409 4410 4411 4412 4413 4414 4415 4416 4417
/**
 * __napi_schedule_irqoff - schedule for receive
 * @n: entry to schedule
 *
 * Variant of __napi_schedule() assuming hard irqs are masked
 */
void __napi_schedule_irqoff(struct napi_struct *n)
{
	____napi_schedule(this_cpu_ptr(&softnet_data), n);
}
EXPORT_SYMBOL(__napi_schedule_irqoff);

4418 4419 4420 4421
void __napi_complete(struct napi_struct *n)
{
	BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));

E
Eric Dumazet 已提交
4422
	list_del_init(&n->poll_list);
4423
	smp_mb__before_atomic();
4424 4425 4426 4427
	clear_bit(NAPI_STATE_SCHED, &n->state);
}
EXPORT_SYMBOL(__napi_complete);

4428
void napi_complete_done(struct napi_struct *n, int work_done)
4429 4430 4431 4432 4433 4434 4435 4436 4437 4438
{
	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;

4439 4440
	if (n->gro_list) {
		unsigned long timeout = 0;
E
Eric Dumazet 已提交
4441

4442 4443 4444 4445 4446 4447 4448 4449 4450
		if (work_done)
			timeout = n->dev->gro_flush_timeout;

		if (timeout)
			hrtimer_start(&n->timer, ns_to_ktime(timeout),
				      HRTIMER_MODE_REL_PINNED);
		else
			napi_gro_flush(n, false);
	}
E
Eric Dumazet 已提交
4451 4452 4453 4454 4455 4456 4457 4458
	if (likely(list_empty(&n->poll_list))) {
		WARN_ON_ONCE(!test_and_clear_bit(NAPI_STATE_SCHED, &n->state));
	} else {
		/* If n->poll_list is not empty, we need to mask irqs */
		local_irq_save(flags);
		__napi_complete(n);
		local_irq_restore(flags);
	}
4459
}
4460
EXPORT_SYMBOL(napi_complete_done);
4461

E
Eliezer Tamir 已提交
4462 4463 4464 4465 4466 4467 4468 4469 4470 4471 4472 4473 4474 4475 4476 4477 4478 4479 4480 4481 4482 4483 4484 4485 4486 4487 4488 4489 4490 4491 4492 4493 4494 4495 4496 4497 4498 4499 4500 4501 4502 4503 4504 4505 4506 4507 4508 4509 4510 4511 4512 4513
/* must be called under rcu_read_lock(), as we dont take a reference */
struct napi_struct *napi_by_id(unsigned int napi_id)
{
	unsigned int hash = napi_id % HASH_SIZE(napi_hash);
	struct napi_struct *napi;

	hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
		if (napi->napi_id == napi_id)
			return napi;

	return NULL;
}
EXPORT_SYMBOL_GPL(napi_by_id);

void napi_hash_add(struct napi_struct *napi)
{
	if (!test_and_set_bit(NAPI_STATE_HASHED, &napi->state)) {

		spin_lock(&napi_hash_lock);

		/* 0 is not a valid id, we also skip an id that is taken
		 * we expect both events to be extremely rare
		 */
		napi->napi_id = 0;
		while (!napi->napi_id) {
			napi->napi_id = ++napi_gen_id;
			if (napi_by_id(napi->napi_id))
				napi->napi_id = 0;
		}

		hlist_add_head_rcu(&napi->napi_hash_node,
			&napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);

		spin_unlock(&napi_hash_lock);
	}
}
EXPORT_SYMBOL_GPL(napi_hash_add);

/* Warning : caller is responsible to make sure rcu grace period
 * is respected before freeing memory containing @napi
 */
void napi_hash_del(struct napi_struct *napi)
{
	spin_lock(&napi_hash_lock);

	if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state))
		hlist_del_rcu(&napi->napi_hash_node);

	spin_unlock(&napi_hash_lock);
}
EXPORT_SYMBOL_GPL(napi_hash_del);

4514 4515 4516 4517 4518 4519 4520 4521 4522 4523 4524
static enum hrtimer_restart napi_watchdog(struct hrtimer *timer)
{
	struct napi_struct *napi;

	napi = container_of(timer, struct napi_struct, timer);
	if (napi->gro_list)
		napi_schedule(napi);

	return HRTIMER_NORESTART;
}

4525 4526 4527 4528
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);
4529 4530
	hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED);
	napi->timer.function = napi_watchdog;
4531
	napi->gro_count = 0;
4532
	napi->gro_list = NULL;
H
Herbert Xu 已提交
4533
	napi->skb = NULL;
4534
	napi->poll = poll;
E
Eric Dumazet 已提交
4535 4536 4537
	if (weight > NAPI_POLL_WEIGHT)
		pr_err_once("netif_napi_add() called with weight %d on device %s\n",
			    weight, dev->name);
4538 4539 4540
	napi->weight = weight;
	list_add(&napi->dev_list, &dev->napi_list);
	napi->dev = dev;
H
Herbert Xu 已提交
4541
#ifdef CONFIG_NETPOLL
4542 4543 4544 4545 4546 4547 4548
	spin_lock_init(&napi->poll_lock);
	napi->poll_owner = -1;
#endif
	set_bit(NAPI_STATE_SCHED, &napi->state);
}
EXPORT_SYMBOL(netif_napi_add);

4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561 4562
void napi_disable(struct napi_struct *n)
{
	might_sleep();
	set_bit(NAPI_STATE_DISABLE, &n->state);

	while (test_and_set_bit(NAPI_STATE_SCHED, &n->state))
		msleep(1);

	hrtimer_cancel(&n->timer);

	clear_bit(NAPI_STATE_DISABLE, &n->state);
}
EXPORT_SYMBOL(napi_disable);

4563 4564
void netif_napi_del(struct napi_struct *napi)
{
4565
	list_del_init(&napi->dev_list);
4566
	napi_free_frags(napi);
4567

E
Eric Dumazet 已提交
4568
	kfree_skb_list(napi->gro_list);
4569
	napi->gro_list = NULL;
4570
	napi->gro_count = 0;
4571 4572 4573
}
EXPORT_SYMBOL(netif_napi_del);

4574 4575 4576 4577 4578 4579 4580 4581 4582 4583 4584 4585 4586 4587 4588 4589 4590 4591 4592 4593 4594 4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607 4608 4609 4610 4611 4612 4613 4614 4615 4616 4617 4618
static int napi_poll(struct napi_struct *n, struct list_head *repoll)
{
	void *have;
	int work, weight;

	list_del_init(&n->poll_list);

	have = netpoll_poll_lock(n);

	weight = n->weight;

	/* 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
	 * accidentally calling ->poll() when NAPI is not scheduled.
	 */
	work = 0;
	if (test_bit(NAPI_STATE_SCHED, &n->state)) {
		work = n->poll(n, weight);
		trace_napi_poll(n);
	}

	WARN_ON_ONCE(work > weight);

	if (likely(work < weight))
		goto out_unlock;

	/* 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.
	 */
	if (unlikely(napi_disable_pending(n))) {
		napi_complete(n);
		goto out_unlock;
	}

	if (n->gro_list) {
		/* flush too old packets
		 * If HZ < 1000, flush all packets.
		 */
		napi_gro_flush(n, HZ >= 1000);
	}

4619 4620 4621 4622 4623 4624 4625 4626 4627
	/* Some drivers may have called napi_schedule
	 * prior to exhausting their budget.
	 */
	if (unlikely(!list_empty(&n->poll_list))) {
		pr_warn_once("%s: Budget exhausted after napi rescheduled\n",
			     n->dev ? n->dev->name : "backlog");
		goto out_unlock;
	}

4628 4629 4630 4631 4632 4633 4634 4635
	list_add_tail(&n->poll_list, repoll);

out_unlock:
	netpoll_poll_unlock(have);

	return work;
}

L
Linus Torvalds 已提交
4636 4637
static void net_rx_action(struct softirq_action *h)
{
4638
	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
4639
	unsigned long time_limit = jiffies + 2;
4640
	int budget = netdev_budget;
E
Eric Dumazet 已提交
4641 4642
	LIST_HEAD(list);
	LIST_HEAD(repoll);
4643

L
Linus Torvalds 已提交
4644
	local_irq_disable();
E
Eric Dumazet 已提交
4645 4646
	list_splice_init(&sd->poll_list, &list);
	local_irq_enable();
L
Linus Torvalds 已提交
4647

H
Herbert Xu 已提交
4648
	for (;;) {
4649
		struct napi_struct *n;
L
Linus Torvalds 已提交
4650

H
Herbert Xu 已提交
4651 4652 4653 4654 4655 4656
		if (list_empty(&list)) {
			if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll))
				return;
			break;
		}

4657 4658 4659
		n = list_first_entry(&list, struct napi_struct, poll_list);
		budget -= napi_poll(n, &repoll);

E
Eric Dumazet 已提交
4660
		/* If softirq window is exhausted then punt.
4661 4662
		 * Allow this to run for 2 jiffies since which will allow
		 * an average latency of 1.5/HZ.
4663
		 */
H
Herbert Xu 已提交
4664 4665 4666 4667 4668
		if (unlikely(budget <= 0 ||
			     time_after_eq(jiffies, time_limit))) {
			sd->time_squeeze++;
			break;
		}
L
Linus Torvalds 已提交
4669
	}
E
Eric Dumazet 已提交
4670 4671 4672 4673 4674 4675 4676 4677 4678

	local_irq_disable();

	list_splice_tail_init(&sd->poll_list, &list);
	list_splice_tail(&repoll, &list);
	list_splice(&list, &sd->poll_list);
	if (!list_empty(&sd->poll_list))
		__raise_softirq_irqoff(NET_RX_SOFTIRQ);

4679
	net_rps_action_and_irq_enable(sd);
L
Linus Torvalds 已提交
4680 4681
}

4682
struct netdev_adjacent {
J
Jiri Pirko 已提交
4683
	struct net_device *dev;
4684 4685

	/* upper master flag, there can only be one master device per list */
J
Jiri Pirko 已提交
4686
	bool master;
4687 4688 4689 4690

	/* counter for the number of times this device was added to us */
	u16 ref_nr;

4691 4692 4693
	/* private field for the users */
	void *private;

J
Jiri Pirko 已提交
4694 4695 4696 4697
	struct list_head list;
	struct rcu_head rcu;
};

4698 4699
static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
						 struct net_device *adj_dev,
4700
						 struct list_head *adj_list)
J
Jiri Pirko 已提交
4701
{
4702 4703
	struct netdev_adjacent *adj;

4704
	list_for_each_entry(adj, adj_list, list) {
4705 4706
		if (adj->dev == adj_dev)
			return adj;
J
Jiri Pirko 已提交
4707 4708 4709 4710 4711 4712 4713 4714 4715 4716 4717 4718 4719 4720 4721 4722 4723 4724
	}
	return NULL;
}

/**
 * netdev_has_upper_dev - Check if device is linked to an upper device
 * @dev: device
 * @upper_dev: upper device to check
 *
 * Find out if a device is linked to specified upper device and return true
 * in case it is. Note that this checks only immediate upper device,
 * not through a complete stack of devices. The caller must hold the RTNL lock.
 */
bool netdev_has_upper_dev(struct net_device *dev,
			  struct net_device *upper_dev)
{
	ASSERT_RTNL();

4725
	return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper);
J
Jiri Pirko 已提交
4726 4727 4728 4729 4730 4731 4732 4733 4734 4735
}
EXPORT_SYMBOL(netdev_has_upper_dev);

/**
 * netdev_has_any_upper_dev - Check if device is linked to some device
 * @dev: device
 *
 * Find out if a device is linked to an upper device and return true in case
 * it is. The caller must hold the RTNL lock.
 */
S
stephen hemminger 已提交
4736
static bool netdev_has_any_upper_dev(struct net_device *dev)
J
Jiri Pirko 已提交
4737 4738 4739
{
	ASSERT_RTNL();

4740
	return !list_empty(&dev->all_adj_list.upper);
J
Jiri Pirko 已提交
4741 4742 4743 4744 4745 4746 4747 4748 4749 4750 4751
}

/**
 * netdev_master_upper_dev_get - Get master upper device
 * @dev: device
 *
 * Find a master upper device and return pointer to it or NULL in case
 * it's not there. The caller must hold the RTNL lock.
 */
struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
{
4752
	struct netdev_adjacent *upper;
J
Jiri Pirko 已提交
4753 4754 4755

	ASSERT_RTNL();

4756
	if (list_empty(&dev->adj_list.upper))
J
Jiri Pirko 已提交
4757 4758
		return NULL;

4759
	upper = list_first_entry(&dev->adj_list.upper,
4760
				 struct netdev_adjacent, list);
J
Jiri Pirko 已提交
4761 4762 4763 4764 4765 4766
	if (likely(upper->master))
		return upper->dev;
	return NULL;
}
EXPORT_SYMBOL(netdev_master_upper_dev_get);

4767 4768 4769 4770 4771 4772 4773 4774 4775 4776
void *netdev_adjacent_get_private(struct list_head *adj_list)
{
	struct netdev_adjacent *adj;

	adj = list_entry(adj_list, struct netdev_adjacent, list);

	return adj->private;
}
EXPORT_SYMBOL(netdev_adjacent_get_private);

4777 4778 4779 4780 4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792 4793 4794 4795 4796 4797 4798 4799 4800 4801 4802
/**
 * netdev_upper_get_next_dev_rcu - Get the next dev from upper list
 * @dev: device
 * @iter: list_head ** of the current position
 *
 * Gets the next device from the dev's upper list, starting from iter
 * position. The caller must hold RCU read lock.
 */
struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
						 struct list_head **iter)
{
	struct netdev_adjacent *upper;

	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());

	upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);

	if (&upper->list == &dev->adj_list.upper)
		return NULL;

	*iter = &upper->list;

	return upper->dev;
}
EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);

4803 4804
/**
 * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
4805 4806 4807 4808 4809 4810
 * @dev: device
 * @iter: list_head ** of the current position
 *
 * Gets the next device from the dev's upper list, starting from iter
 * position. The caller must hold RCU read lock.
 */
4811 4812
struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
						     struct list_head **iter)
4813 4814 4815
{
	struct netdev_adjacent *upper;

4816
	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
4817 4818 4819

	upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);

4820
	if (&upper->list == &dev->all_adj_list.upper)
4821 4822 4823 4824 4825 4826
		return NULL;

	*iter = &upper->list;

	return upper->dev;
}
4827
EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
4828

4829 4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840 4841 4842 4843 4844 4845 4846 4847 4848 4849
/**
 * netdev_lower_get_next_private - Get the next ->private from the
 *				   lower neighbour list
 * @dev: device
 * @iter: list_head ** of the current position
 *
 * Gets the next netdev_adjacent->private from the dev's lower neighbour
 * list, starting from iter position. The caller must hold either hold the
 * RTNL lock or its own locking that guarantees that the neighbour lower
 * list will remain unchainged.
 */
void *netdev_lower_get_next_private(struct net_device *dev,
				    struct list_head **iter)
{
	struct netdev_adjacent *lower;

	lower = list_entry(*iter, struct netdev_adjacent, list);

	if (&lower->list == &dev->adj_list.lower)
		return NULL;

4850
	*iter = lower->list.next;
4851 4852 4853 4854 4855 4856 4857 4858 4859 4860 4861 4862 4863 4864 4865 4866 4867 4868 4869 4870 4871 4872 4873 4874 4875 4876 4877

	return lower->private;
}
EXPORT_SYMBOL(netdev_lower_get_next_private);

/**
 * netdev_lower_get_next_private_rcu - Get the next ->private from the
 *				       lower neighbour list, RCU
 *				       variant
 * @dev: device
 * @iter: list_head ** of the current position
 *
 * Gets the next netdev_adjacent->private from the dev's lower neighbour
 * list, starting from iter position. The caller must hold RCU read lock.
 */
void *netdev_lower_get_next_private_rcu(struct net_device *dev,
					struct list_head **iter)
{
	struct netdev_adjacent *lower;

	WARN_ON_ONCE(!rcu_read_lock_held());

	lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);

	if (&lower->list == &dev->adj_list.lower)
		return NULL;

4878
	*iter = &lower->list;
4879 4880 4881 4882 4883

	return lower->private;
}
EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);

4884 4885 4886 4887 4888 4889 4890 4891 4892 4893 4894 4895 4896 4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909
/**
 * netdev_lower_get_next - Get the next device from the lower neighbour
 *                         list
 * @dev: device
 * @iter: list_head ** of the current position
 *
 * Gets the next netdev_adjacent from the dev's lower neighbour
 * list, starting from iter position. The caller must hold RTNL lock or
 * its own locking that guarantees that the neighbour lower
 * list will remain unchainged.
 */
void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
{
	struct netdev_adjacent *lower;

	lower = list_entry((*iter)->next, struct netdev_adjacent, list);

	if (&lower->list == &dev->adj_list.lower)
		return NULL;

	*iter = &lower->list;

	return lower->dev;
}
EXPORT_SYMBOL(netdev_lower_get_next);

4910 4911 4912 4913 4914 4915 4916 4917 4918 4919 4920 4921 4922 4923 4924 4925 4926 4927 4928 4929 4930
/**
 * netdev_lower_get_first_private_rcu - Get the first ->private from the
 *				       lower neighbour list, RCU
 *				       variant
 * @dev: device
 *
 * Gets the first netdev_adjacent->private from the dev's lower neighbour
 * list. The caller must hold RCU read lock.
 */
void *netdev_lower_get_first_private_rcu(struct net_device *dev)
{
	struct netdev_adjacent *lower;

	lower = list_first_or_null_rcu(&dev->adj_list.lower,
			struct netdev_adjacent, list);
	if (lower)
		return lower->private;
	return NULL;
}
EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);

J
Jiri Pirko 已提交
4931 4932 4933 4934 4935 4936 4937 4938 4939
/**
 * netdev_master_upper_dev_get_rcu - Get master upper device
 * @dev: device
 *
 * Find a master upper device and return pointer to it or NULL in case
 * it's not there. The caller must hold the RCU read lock.
 */
struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
{
4940
	struct netdev_adjacent *upper;
J
Jiri Pirko 已提交
4941

4942
	upper = list_first_or_null_rcu(&dev->adj_list.upper,
4943
				       struct netdev_adjacent, list);
J
Jiri Pirko 已提交
4944 4945 4946 4947 4948 4949
	if (upper && likely(upper->master))
		return upper->dev;
	return NULL;
}
EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);

4950
static int netdev_adjacent_sysfs_add(struct net_device *dev,
4951 4952 4953 4954 4955 4956 4957 4958 4959
			      struct net_device *adj_dev,
			      struct list_head *dev_list)
{
	char linkname[IFNAMSIZ+7];
	sprintf(linkname, dev_list == &dev->adj_list.upper ?
		"upper_%s" : "lower_%s", adj_dev->name);
	return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj),
				 linkname);
}
4960
static void netdev_adjacent_sysfs_del(struct net_device *dev,
4961 4962 4963 4964 4965 4966 4967 4968 4969
			       char *name,
			       struct list_head *dev_list)
{
	char linkname[IFNAMSIZ+7];
	sprintf(linkname, dev_list == &dev->adj_list.upper ?
		"upper_%s" : "lower_%s", name);
	sysfs_remove_link(&(dev->dev.kobj), linkname);
}

4970 4971 4972 4973 4974 4975 4976 4977
static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev,
						 struct net_device *adj_dev,
						 struct list_head *dev_list)
{
	return (dev_list == &dev->adj_list.upper ||
		dev_list == &dev->adj_list.lower) &&
		net_eq(dev_net(dev), dev_net(adj_dev));
}
4978

4979 4980
static int __netdev_adjacent_dev_insert(struct net_device *dev,
					struct net_device *adj_dev,
4981
					struct list_head *dev_list,
4982
					void *private, bool master)
4983 4984
{
	struct netdev_adjacent *adj;
4985
	int ret;
4986

4987
	adj = __netdev_find_adj(dev, adj_dev, dev_list);
4988 4989 4990 4991 4992 4993 4994 4995 4996 4997 4998 4999 5000

	if (adj) {
		adj->ref_nr++;
		return 0;
	}

	adj = kmalloc(sizeof(*adj), GFP_KERNEL);
	if (!adj)
		return -ENOMEM;

	adj->dev = adj_dev;
	adj->master = master;
	adj->ref_nr = 1;
5001
	adj->private = private;
5002
	dev_hold(adj_dev);
5003 5004 5005

	pr_debug("dev_hold for %s, because of link added from %s to %s\n",
		 adj_dev->name, dev->name, adj_dev->name);
5006

5007
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
5008
		ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
5009 5010 5011 5012
		if (ret)
			goto free_adj;
	}

5013
	/* Ensure that master link is always the first item in list. */
5014 5015 5016 5017
	if (master) {
		ret = sysfs_create_link(&(dev->dev.kobj),
					&(adj_dev->dev.kobj), "master");
		if (ret)
5018
			goto remove_symlinks;
5019

5020
		list_add_rcu(&adj->list, dev_list);
5021
	} else {
5022
		list_add_tail_rcu(&adj->list, dev_list);
5023
	}
5024 5025

	return 0;
5026

5027
remove_symlinks:
5028
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
5029
		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
5030 5031
free_adj:
	kfree(adj);
5032
	dev_put(adj_dev);
5033 5034

	return ret;
5035 5036
}

S
stephen hemminger 已提交
5037 5038 5039
static void __netdev_adjacent_dev_remove(struct net_device *dev,
					 struct net_device *adj_dev,
					 struct list_head *dev_list)
5040 5041 5042
{
	struct netdev_adjacent *adj;

5043
	adj = __netdev_find_adj(dev, adj_dev, dev_list);
5044

5045 5046 5047
	if (!adj) {
		pr_err("tried to remove device %s from %s\n",
		       dev->name, adj_dev->name);
5048
		BUG();
5049
	}
5050 5051

	if (adj->ref_nr > 1) {
5052 5053
		pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name,
			 adj->ref_nr-1);
5054 5055 5056 5057
		adj->ref_nr--;
		return;
	}

5058 5059 5060
	if (adj->master)
		sysfs_remove_link(&(dev->dev.kobj), "master");

5061
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
5062
		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
5063

5064
	list_del_rcu(&adj->list);
5065 5066
	pr_debug("dev_put for %s, because link removed from %s to %s\n",
		 adj_dev->name, dev->name, adj_dev->name);
5067 5068 5069 5070
	dev_put(adj_dev);
	kfree_rcu(adj, rcu);
}

S
stephen hemminger 已提交
5071 5072 5073 5074 5075
static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
					    struct net_device *upper_dev,
					    struct list_head *up_list,
					    struct list_head *down_list,
					    void *private, bool master)
5076 5077 5078
{
	int ret;

5079 5080
	ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, private,
					   master);
5081 5082 5083
	if (ret)
		return ret;

5084 5085
	ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, private,
					   false);
5086
	if (ret) {
5087
		__netdev_adjacent_dev_remove(dev, upper_dev, up_list);
5088 5089 5090 5091 5092 5093
		return ret;
	}

	return 0;
}

S
stephen hemminger 已提交
5094 5095
static int __netdev_adjacent_dev_link(struct net_device *dev,
				      struct net_device *upper_dev)
5096
{
5097 5098 5099
	return __netdev_adjacent_dev_link_lists(dev, upper_dev,
						&dev->all_adj_list.upper,
						&upper_dev->all_adj_list.lower,
5100
						NULL, false);
5101 5102
}

S
stephen hemminger 已提交
5103 5104 5105 5106
static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
					       struct net_device *upper_dev,
					       struct list_head *up_list,
					       struct list_head *down_list)
5107
{
5108 5109
	__netdev_adjacent_dev_remove(dev, upper_dev, up_list);
	__netdev_adjacent_dev_remove(upper_dev, dev, down_list);
5110 5111
}

S
stephen hemminger 已提交
5112 5113
static void __netdev_adjacent_dev_unlink(struct net_device *dev,
					 struct net_device *upper_dev)
5114
{
5115 5116 5117 5118 5119
	__netdev_adjacent_dev_unlink_lists(dev, upper_dev,
					   &dev->all_adj_list.upper,
					   &upper_dev->all_adj_list.lower);
}

S
stephen hemminger 已提交
5120 5121 5122
static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
						struct net_device *upper_dev,
						void *private, bool master)
5123 5124 5125 5126 5127 5128 5129 5130 5131
{
	int ret = __netdev_adjacent_dev_link(dev, upper_dev);

	if (ret)
		return ret;

	ret = __netdev_adjacent_dev_link_lists(dev, upper_dev,
					       &dev->adj_list.upper,
					       &upper_dev->adj_list.lower,
5132
					       private, master);
5133 5134 5135 5136 5137 5138
	if (ret) {
		__netdev_adjacent_dev_unlink(dev, upper_dev);
		return ret;
	}

	return 0;
5139 5140
}

S
stephen hemminger 已提交
5141 5142
static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
						   struct net_device *upper_dev)
5143 5144 5145 5146 5147 5148
{
	__netdev_adjacent_dev_unlink(dev, upper_dev);
	__netdev_adjacent_dev_unlink_lists(dev, upper_dev,
					   &dev->adj_list.upper,
					   &upper_dev->adj_list.lower);
}
5149

J
Jiri Pirko 已提交
5150
static int __netdev_upper_dev_link(struct net_device *dev,
5151 5152
				   struct net_device *upper_dev, bool master,
				   void *private)
J
Jiri Pirko 已提交
5153
{
5154 5155
	struct netdev_adjacent *i, *j, *to_i, *to_j;
	int ret = 0;
J
Jiri Pirko 已提交
5156 5157 5158 5159 5160 5161 5162

	ASSERT_RTNL();

	if (dev == upper_dev)
		return -EBUSY;

	/* To prevent loops, check if dev is not upper device to upper_dev. */
5163
	if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper))
J
Jiri Pirko 已提交
5164 5165
		return -EBUSY;

5166
	if (__netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper))
J
Jiri Pirko 已提交
5167 5168 5169 5170 5171
		return -EEXIST;

	if (master && netdev_master_upper_dev_get(dev))
		return -EBUSY;

5172 5173
	ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private,
						   master);
5174 5175
	if (ret)
		return ret;
J
Jiri Pirko 已提交
5176

5177
	/* Now that we linked these devs, make all the upper_dev's
5178
	 * all_adj_list.upper visible to every dev's all_adj_list.lower an
5179 5180 5181
	 * versa, and don't forget the devices itself. All of these
	 * links are non-neighbours.
	 */
5182 5183 5184 5185
	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
		list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
			pr_debug("Interlinking %s with %s, non-neighbour\n",
				 i->dev->name, j->dev->name);
5186 5187 5188 5189 5190 5191 5192
			ret = __netdev_adjacent_dev_link(i->dev, j->dev);
			if (ret)
				goto rollback_mesh;
		}
	}

	/* add dev to every upper_dev's upper device */
5193 5194 5195
	list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
		pr_debug("linking %s's upper device %s with %s\n",
			 upper_dev->name, i->dev->name, dev->name);
5196 5197 5198 5199 5200 5201
		ret = __netdev_adjacent_dev_link(dev, i->dev);
		if (ret)
			goto rollback_upper_mesh;
	}

	/* add upper_dev to every dev's lower device */
5202 5203 5204
	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
		pr_debug("linking %s's lower device %s with %s\n", dev->name,
			 i->dev->name, upper_dev->name);
5205 5206 5207 5208
		ret = __netdev_adjacent_dev_link(i->dev, upper_dev);
		if (ret)
			goto rollback_lower_mesh;
	}
J
Jiri Pirko 已提交
5209

5210
	call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
J
Jiri Pirko 已提交
5211
	return 0;
5212 5213 5214

rollback_lower_mesh:
	to_i = i;
5215
	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5216 5217 5218 5219 5220 5221 5222 5223 5224
		if (i == to_i)
			break;
		__netdev_adjacent_dev_unlink(i->dev, upper_dev);
	}

	i = NULL;

rollback_upper_mesh:
	to_i = i;
5225
	list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
5226 5227 5228 5229 5230 5231 5232 5233 5234 5235
		if (i == to_i)
			break;
		__netdev_adjacent_dev_unlink(dev, i->dev);
	}

	i = j = NULL;

rollback_mesh:
	to_i = i;
	to_j = j;
5236 5237
	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
		list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
5238 5239 5240 5241 5242 5243 5244 5245
			if (i == to_i && j == to_j)
				break;
			__netdev_adjacent_dev_unlink(i->dev, j->dev);
		}
		if (i == to_i)
			break;
	}

5246
	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5247 5248

	return ret;
J
Jiri Pirko 已提交
5249 5250 5251 5252 5253 5254 5255 5256 5257 5258 5259 5260 5261 5262 5263
}

/**
 * netdev_upper_dev_link - Add a link to the upper device
 * @dev: device
 * @upper_dev: new upper device
 *
 * Adds a link to device which is upper to this one. The caller must hold
 * the RTNL lock. On a failure a negative errno code is returned.
 * On success the reference counts are adjusted and the function
 * returns zero.
 */
int netdev_upper_dev_link(struct net_device *dev,
			  struct net_device *upper_dev)
{
5264
	return __netdev_upper_dev_link(dev, upper_dev, false, NULL);
J
Jiri Pirko 已提交
5265 5266 5267 5268 5269 5270 5271 5272 5273 5274 5275 5276 5277 5278 5279 5280 5281
}
EXPORT_SYMBOL(netdev_upper_dev_link);

/**
 * netdev_master_upper_dev_link - Add a master link to the upper device
 * @dev: device
 * @upper_dev: new upper device
 *
 * Adds a link to device which is upper to this one. In this case, only
 * one master upper device can be linked, although other non-master devices
 * might be linked as well. The caller must hold the RTNL lock.
 * On a failure a negative errno code is returned. On success the reference
 * counts are adjusted and the function returns zero.
 */
int netdev_master_upper_dev_link(struct net_device *dev,
				 struct net_device *upper_dev)
{
5282
	return __netdev_upper_dev_link(dev, upper_dev, true, NULL);
J
Jiri Pirko 已提交
5283 5284 5285
}
EXPORT_SYMBOL(netdev_master_upper_dev_link);

5286 5287 5288 5289 5290 5291 5292 5293
int netdev_master_upper_dev_link_private(struct net_device *dev,
					 struct net_device *upper_dev,
					 void *private)
{
	return __netdev_upper_dev_link(dev, upper_dev, true, private);
}
EXPORT_SYMBOL(netdev_master_upper_dev_link_private);

J
Jiri Pirko 已提交
5294 5295 5296 5297 5298 5299 5300 5301 5302 5303 5304
/**
 * netdev_upper_dev_unlink - Removes a link to upper device
 * @dev: device
 * @upper_dev: new upper device
 *
 * Removes a link to device which is upper to this one. The caller must hold
 * the RTNL lock.
 */
void netdev_upper_dev_unlink(struct net_device *dev,
			     struct net_device *upper_dev)
{
5305
	struct netdev_adjacent *i, *j;
J
Jiri Pirko 已提交
5306 5307
	ASSERT_RTNL();

5308
	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5309 5310 5311 5312 5313

	/* Here is the tricky part. We must remove all dev's lower
	 * devices from all upper_dev's upper devices and vice
	 * versa, to maintain the graph relationship.
	 */
5314 5315
	list_for_each_entry(i, &dev->all_adj_list.lower, list)
		list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
5316 5317 5318 5319 5320
			__netdev_adjacent_dev_unlink(i->dev, j->dev);

	/* remove also the devices itself from lower/upper device
	 * list
	 */
5321
	list_for_each_entry(i, &dev->all_adj_list.lower, list)
5322 5323
		__netdev_adjacent_dev_unlink(i->dev, upper_dev);

5324
	list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
5325 5326
		__netdev_adjacent_dev_unlink(dev, i->dev);

5327
	call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
J
Jiri Pirko 已提交
5328 5329 5330
}
EXPORT_SYMBOL(netdev_upper_dev_unlink);

5331 5332 5333
/**
 * netdev_bonding_info_change - Dispatch event about slave change
 * @dev: device
5334
 * @bonding_info: info to dispatch
5335 5336 5337 5338 5339 5340 5341 5342 5343 5344 5345 5346 5347 5348 5349 5350
 *
 * Send NETDEV_BONDING_INFO to netdev notifiers with info.
 * The caller must hold the RTNL lock.
 */
void netdev_bonding_info_change(struct net_device *dev,
				struct netdev_bonding_info *bonding_info)
{
	struct netdev_notifier_bonding_info	info;

	memcpy(&info.bonding_info, bonding_info,
	       sizeof(struct netdev_bonding_info));
	call_netdevice_notifiers_info(NETDEV_BONDING_INFO, dev,
				      &info.info);
}
EXPORT_SYMBOL(netdev_bonding_info_change);

E
Eric Dumazet 已提交
5351
static void netdev_adjacent_add_links(struct net_device *dev)
5352 5353 5354 5355 5356 5357 5358 5359 5360 5361 5362 5363 5364 5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375
{
	struct netdev_adjacent *iter;

	struct net *net = dev_net(dev);

	list_for_each_entry(iter, &dev->adj_list.upper, list) {
		if (!net_eq(net,dev_net(iter->dev)))
			continue;
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.lower);
		netdev_adjacent_sysfs_add(dev, iter->dev,
					  &dev->adj_list.upper);
	}

	list_for_each_entry(iter, &dev->adj_list.lower, list) {
		if (!net_eq(net,dev_net(iter->dev)))
			continue;
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.upper);
		netdev_adjacent_sysfs_add(dev, iter->dev,
					  &dev->adj_list.lower);
	}
}

E
Eric Dumazet 已提交
5376
static void netdev_adjacent_del_links(struct net_device *dev)
5377 5378 5379 5380 5381 5382 5383 5384 5385 5386 5387 5388 5389 5390 5391 5392 5393 5394 5395 5396 5397 5398 5399 5400
{
	struct netdev_adjacent *iter;

	struct net *net = dev_net(dev);

	list_for_each_entry(iter, &dev->adj_list.upper, list) {
		if (!net_eq(net,dev_net(iter->dev)))
			continue;
		netdev_adjacent_sysfs_del(iter->dev, dev->name,
					  &iter->dev->adj_list.lower);
		netdev_adjacent_sysfs_del(dev, iter->dev->name,
					  &dev->adj_list.upper);
	}

	list_for_each_entry(iter, &dev->adj_list.lower, list) {
		if (!net_eq(net,dev_net(iter->dev)))
			continue;
		netdev_adjacent_sysfs_del(iter->dev, dev->name,
					  &iter->dev->adj_list.upper);
		netdev_adjacent_sysfs_del(dev, iter->dev->name,
					  &dev->adj_list.lower);
	}
}

5401
void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
5402
{
5403
	struct netdev_adjacent *iter;
5404

5405 5406
	struct net *net = dev_net(dev);

5407
	list_for_each_entry(iter, &dev->adj_list.upper, list) {
5408 5409
		if (!net_eq(net,dev_net(iter->dev)))
			continue;
5410 5411 5412 5413 5414
		netdev_adjacent_sysfs_del(iter->dev, oldname,
					  &iter->dev->adj_list.lower);
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.lower);
	}
5415

5416
	list_for_each_entry(iter, &dev->adj_list.lower, list) {
5417 5418
		if (!net_eq(net,dev_net(iter->dev)))
			continue;
5419 5420 5421 5422 5423
		netdev_adjacent_sysfs_del(iter->dev, oldname,
					  &iter->dev->adj_list.upper);
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.upper);
	}
5424 5425 5426 5427 5428 5429 5430 5431 5432 5433 5434 5435 5436 5437 5438 5439 5440
}

void *netdev_lower_dev_get_private(struct net_device *dev,
				   struct net_device *lower_dev)
{
	struct netdev_adjacent *lower;

	if (!lower_dev)
		return NULL;
	lower = __netdev_find_adj(dev, lower_dev, &dev->adj_list.lower);
	if (!lower)
		return NULL;

	return lower->private;
}
EXPORT_SYMBOL(netdev_lower_dev_get_private);

5441 5442 5443 5444 5445 5446 5447 5448 5449 5450 5451 5452 5453 5454 5455 5456 5457 5458 5459 5460 5461 5462 5463 5464

int dev_get_nest_level(struct net_device *dev,
		       bool (*type_check)(struct net_device *dev))
{
	struct net_device *lower = NULL;
	struct list_head *iter;
	int max_nest = -1;
	int nest;

	ASSERT_RTNL();

	netdev_for_each_lower_dev(dev, lower, iter) {
		nest = dev_get_nest_level(lower, type_check);
		if (max_nest < nest)
			max_nest = nest;
	}

	if (type_check(dev))
		max_nest++;

	return max_nest;
}
EXPORT_SYMBOL(dev_get_nest_level);

5465 5466
static void dev_change_rx_flags(struct net_device *dev, int flags)
{
5467 5468
	const struct net_device_ops *ops = dev->netdev_ops;

5469
	if (ops->ndo_change_rx_flags)
5470
		ops->ndo_change_rx_flags(dev, flags);
5471 5472
}

5473
static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
L
Linus Torvalds 已提交
5474
{
5475
	unsigned int old_flags = dev->flags;
5476 5477
	kuid_t uid;
	kgid_t gid;
L
Linus Torvalds 已提交
5478

5479 5480
	ASSERT_RTNL();

5481 5482 5483 5484 5485 5486 5487 5488 5489 5490 5491
	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;
5492 5493
			pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
				dev->name);
5494 5495 5496
			return -EOVERFLOW;
		}
	}
5497
	if (dev->flags != old_flags) {
5498 5499 5500
		pr_info("device %s %s promiscuous mode\n",
			dev->name,
			dev->flags & IFF_PROMISC ? "entered" : "left");
5501 5502
		if (audit_enabled) {
			current_uid_gid(&uid, &gid);
5503 5504 5505 5506 5507
			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),
5508
				from_kuid(&init_user_ns, audit_get_loginuid(current)),
5509 5510
				from_kuid(&init_user_ns, uid),
				from_kgid(&init_user_ns, gid),
5511
				audit_get_sessionid(current));
5512
		}
5513

5514
		dev_change_rx_flags(dev, IFF_PROMISC);
L
Linus Torvalds 已提交
5515
	}
5516 5517
	if (notify)
		__dev_notify_flags(dev, old_flags, IFF_PROMISC);
5518
	return 0;
L
Linus Torvalds 已提交
5519 5520
}

5521 5522 5523 5524 5525 5526 5527 5528 5529
/**
 *	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.
5530
 *	Return 0 if successful or a negative errno code on error.
5531
 */
5532
int dev_set_promiscuity(struct net_device *dev, int inc)
5533
{
5534
	unsigned int old_flags = dev->flags;
5535
	int err;
5536

5537
	err = __dev_set_promiscuity(dev, inc, true);
5538
	if (err < 0)
5539
		return err;
5540 5541
	if (dev->flags != old_flags)
		dev_set_rx_mode(dev);
5542
	return err;
5543
}
E
Eric Dumazet 已提交
5544
EXPORT_SYMBOL(dev_set_promiscuity);
5545

5546
static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
L
Linus Torvalds 已提交
5547
{
5548
	unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
L
Linus Torvalds 已提交
5549

5550 5551
	ASSERT_RTNL();

L
Linus Torvalds 已提交
5552
	dev->flags |= IFF_ALLMULTI;
5553 5554 5555 5556 5557 5558 5559 5560 5561 5562
	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;
5563 5564
			pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
				dev->name);
5565 5566 5567
			return -EOVERFLOW;
		}
	}
5568
	if (dev->flags ^ old_flags) {
5569
		dev_change_rx_flags(dev, IFF_ALLMULTI);
5570
		dev_set_rx_mode(dev);
5571 5572 5573
		if (notify)
			__dev_notify_flags(dev, old_flags,
					   dev->gflags ^ old_gflags);
5574
	}
5575
	return 0;
5576
}
5577 5578 5579 5580 5581 5582 5583 5584 5585 5586 5587 5588 5589 5590 5591 5592 5593 5594

/**
 *	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.
 *	Return 0 if successful or a negative errno code on error.
 */

int dev_set_allmulti(struct net_device *dev, int inc)
{
	return __dev_set_allmulti(dev, inc, true);
}
E
Eric Dumazet 已提交
5595
EXPORT_SYMBOL(dev_set_allmulti);
5596 5597 5598 5599

/*
 *	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
5600
 *	filtering it is put in promiscuous mode while unicast addresses
5601 5602 5603 5604
 *	are present.
 */
void __dev_set_rx_mode(struct net_device *dev)
{
5605 5606
	const struct net_device_ops *ops = dev->netdev_ops;

5607 5608 5609 5610 5611
	/* dev_open will call this function so the list will stay sane. */
	if (!(dev->flags&IFF_UP))
		return;

	if (!netif_device_present(dev))
5612
		return;
5613

5614
	if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
5615 5616 5617
		/* Unicast addresses changes may only happen under the rtnl,
		 * therefore calling __dev_set_promiscuity here is safe.
		 */
5618
		if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
5619
			__dev_set_promiscuity(dev, 1, false);
5620
			dev->uc_promisc = true;
5621
		} else if (netdev_uc_empty(dev) && dev->uc_promisc) {
5622
			__dev_set_promiscuity(dev, -1, false);
5623
			dev->uc_promisc = false;
5624 5625
		}
	}
5626 5627 5628

	if (ops->ndo_set_rx_mode)
		ops->ndo_set_rx_mode(dev);
5629 5630 5631 5632
}

void dev_set_rx_mode(struct net_device *dev)
{
5633
	netif_addr_lock_bh(dev);
5634
	__dev_set_rx_mode(dev);
5635
	netif_addr_unlock_bh(dev);
L
Linus Torvalds 已提交
5636 5637
}

5638 5639 5640 5641 5642 5643
/**
 *	dev_get_flags - get flags reported to userspace
 *	@dev: device
 *
 *	Get the combination of flag bits exported through APIs to userspace.
 */
5644
unsigned int dev_get_flags(const struct net_device *dev)
L
Linus Torvalds 已提交
5645
{
5646
	unsigned int flags;
L
Linus Torvalds 已提交
5647 5648 5649

	flags = (dev->flags & ~(IFF_PROMISC |
				IFF_ALLMULTI |
S
Stefan Rompf 已提交
5650 5651 5652
				IFF_RUNNING |
				IFF_LOWER_UP |
				IFF_DORMANT)) |
L
Linus Torvalds 已提交
5653 5654 5655
		(dev->gflags & (IFF_PROMISC |
				IFF_ALLMULTI));

S
Stefan Rompf 已提交
5656 5657 5658 5659 5660 5661 5662 5663
	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
5664 5665 5666

	return flags;
}
E
Eric Dumazet 已提交
5667
EXPORT_SYMBOL(dev_get_flags);
L
Linus Torvalds 已提交
5668

5669
int __dev_change_flags(struct net_device *dev, unsigned int flags)
L
Linus Torvalds 已提交
5670
{
5671
	unsigned int old_flags = dev->flags;
5672
	int ret;
L
Linus Torvalds 已提交
5673

5674 5675
	ASSERT_RTNL();

L
Linus Torvalds 已提交
5676 5677 5678 5679 5680 5681 5682 5683 5684 5685 5686 5687 5688 5689
	/*
	 *	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.
	 */

5690 5691
	if ((old_flags ^ flags) & IFF_MULTICAST)
		dev_change_rx_flags(dev, IFF_MULTICAST);
5692

5693
	dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
5694 5695 5696 5697 5698 5699 5700 5701

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

	ret = 0;
5702
	if ((old_flags ^ flags) & IFF_UP)
5703
		ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
L
Linus Torvalds 已提交
5704 5705

	if ((flags ^ dev->gflags) & IFF_PROMISC) {
E
Eric Dumazet 已提交
5706
		int inc = (flags & IFF_PROMISC) ? 1 : -1;
5707
		unsigned int old_flags = dev->flags;
E
Eric Dumazet 已提交
5708

L
Linus Torvalds 已提交
5709
		dev->gflags ^= IFF_PROMISC;
5710 5711 5712 5713

		if (__dev_set_promiscuity(dev, inc, false) >= 0)
			if (dev->flags != old_flags)
				dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
5714 5715 5716 5717 5718 5719 5720
	}

	/* 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
5721 5722
		int inc = (flags & IFF_ALLMULTI) ? 1 : -1;

L
Linus Torvalds 已提交
5723
		dev->gflags ^= IFF_ALLMULTI;
5724
		__dev_set_allmulti(dev, inc, false);
L
Linus Torvalds 已提交
5725 5726
	}

5727 5728 5729
	return ret;
}

5730 5731
void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
			unsigned int gchanges)
5732 5733 5734
{
	unsigned int changes = dev->flags ^ old_flags;

5735
	if (gchanges)
5736
		rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
5737

5738 5739 5740 5741 5742 5743 5744 5745
	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 &&
5746 5747 5748 5749 5750 5751 5752
	    (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
		struct netdev_notifier_change_info change_info;

		change_info.flags_changed = changes;
		call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
					      &change_info.info);
	}
5753 5754 5755 5756 5757 5758 5759 5760 5761 5762
}

/**
 *	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.
 */
5763
int dev_change_flags(struct net_device *dev, unsigned int flags)
5764
{
5765
	int ret;
5766
	unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
5767 5768 5769 5770 5771

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

5772
	changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
5773
	__dev_notify_flags(dev, old_flags, changes);
L
Linus Torvalds 已提交
5774 5775
	return ret;
}
E
Eric Dumazet 已提交
5776
EXPORT_SYMBOL(dev_change_flags);
L
Linus Torvalds 已提交
5777

5778 5779 5780 5781 5782 5783 5784 5785 5786 5787 5788
static int __dev_set_mtu(struct net_device *dev, int new_mtu)
{
	const struct net_device_ops *ops = dev->netdev_ops;

	if (ops->ndo_change_mtu)
		return ops->ndo_change_mtu(dev, new_mtu);

	dev->mtu = new_mtu;
	return 0;
}

5789 5790 5791 5792 5793 5794 5795
/**
 *	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
5796 5797
int dev_set_mtu(struct net_device *dev, int new_mtu)
{
5798
	int err, orig_mtu;
L
Linus Torvalds 已提交
5799 5800 5801 5802 5803 5804 5805 5806 5807 5808 5809

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

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

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

5810 5811 5812 5813
	err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
	err = notifier_to_errno(err);
	if (err)
		return err;
5814

5815 5816
	orig_mtu = dev->mtu;
	err = __dev_set_mtu(dev, new_mtu);
5817

5818 5819 5820 5821 5822 5823 5824 5825 5826 5827 5828
	if (!err) {
		err = call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
		err = notifier_to_errno(err);
		if (err) {
			/* setting mtu back and notifying everyone again,
			 * so that they have a chance to revert changes.
			 */
			__dev_set_mtu(dev, orig_mtu);
			call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
		}
	}
L
Linus Torvalds 已提交
5829 5830
	return err;
}
E
Eric Dumazet 已提交
5831
EXPORT_SYMBOL(dev_set_mtu);
L
Linus Torvalds 已提交
5832

5833 5834 5835 5836 5837 5838 5839 5840 5841 5842 5843
/**
 *	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);

5844 5845 5846 5847 5848 5849 5850
/**
 *	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
5851 5852
int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
{
5853
	const struct net_device_ops *ops = dev->netdev_ops;
L
Linus Torvalds 已提交
5854 5855
	int err;

5856
	if (!ops->ndo_set_mac_address)
L
Linus Torvalds 已提交
5857 5858 5859 5860 5861
		return -EOPNOTSUPP;
	if (sa->sa_family != dev->type)
		return -EINVAL;
	if (!netif_device_present(dev))
		return -ENODEV;
5862
	err = ops->ndo_set_mac_address(dev, sa);
5863 5864
	if (err)
		return err;
J
Jiri Pirko 已提交
5865
	dev->addr_assign_type = NET_ADDR_SET;
5866
	call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
5867
	add_device_randomness(dev->dev_addr, dev->addr_len);
5868
	return 0;
L
Linus Torvalds 已提交
5869
}
E
Eric Dumazet 已提交
5870
EXPORT_SYMBOL(dev_set_mac_address);
L
Linus Torvalds 已提交
5871

J
Jiri Pirko 已提交
5872 5873 5874
/**
 *	dev_change_carrier - Change device carrier
 *	@dev: device
5875
 *	@new_carrier: new value
J
Jiri Pirko 已提交
5876 5877 5878 5879 5880 5881 5882 5883 5884 5885 5886 5887 5888 5889 5890
 *
 *	Change device carrier
 */
int dev_change_carrier(struct net_device *dev, bool new_carrier)
{
	const struct net_device_ops *ops = dev->netdev_ops;

	if (!ops->ndo_change_carrier)
		return -EOPNOTSUPP;
	if (!netif_device_present(dev))
		return -ENODEV;
	return ops->ndo_change_carrier(dev, new_carrier);
}
EXPORT_SYMBOL(dev_change_carrier);

5891 5892 5893 5894 5895 5896 5897 5898
/**
 *	dev_get_phys_port_id - Get device physical port ID
 *	@dev: device
 *	@ppid: port ID
 *
 *	Get device physical port ID
 */
int dev_get_phys_port_id(struct net_device *dev,
5899
			 struct netdev_phys_item_id *ppid)
5900 5901 5902 5903 5904 5905 5906 5907 5908
{
	const struct net_device_ops *ops = dev->netdev_ops;

	if (!ops->ndo_get_phys_port_id)
		return -EOPNOTSUPP;
	return ops->ndo_get_phys_port_id(dev, ppid);
}
EXPORT_SYMBOL(dev_get_phys_port_id);

5909 5910 5911 5912 5913 5914 5915 5916 5917 5918 5919 5920 5921 5922 5923 5924 5925 5926
/**
 *	dev_get_phys_port_name - Get device physical port name
 *	@dev: device
 *	@name: port name
 *
 *	Get device physical port name
 */
int dev_get_phys_port_name(struct net_device *dev,
			   char *name, size_t len)
{
	const struct net_device_ops *ops = dev->netdev_ops;

	if (!ops->ndo_get_phys_port_name)
		return -EOPNOTSUPP;
	return ops->ndo_get_phys_port_name(dev, name, len);
}
EXPORT_SYMBOL(dev_get_phys_port_name);

L
Linus Torvalds 已提交
5927 5928
/**
 *	dev_new_index	-	allocate an ifindex
5929
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
5930 5931 5932 5933 5934
 *
 *	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.
 */
5935
static int dev_new_index(struct net *net)
L
Linus Torvalds 已提交
5936
{
5937
	int ifindex = net->ifindex;
L
Linus Torvalds 已提交
5938 5939 5940
	for (;;) {
		if (++ifindex <= 0)
			ifindex = 1;
5941
		if (!__dev_get_by_index(net, ifindex))
5942
			return net->ifindex = ifindex;
L
Linus Torvalds 已提交
5943 5944 5945 5946
	}
}

/* Delayed registration/unregisteration */
5947
static LIST_HEAD(net_todo_list);
5948
DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
L
Linus Torvalds 已提交
5949

5950
static void net_set_todo(struct net_device *dev)
L
Linus Torvalds 已提交
5951 5952
{
	list_add_tail(&dev->todo_list, &net_todo_list);
5953
	dev_net(dev)->dev_unreg_count++;
L
Linus Torvalds 已提交
5954 5955
}

5956
static void rollback_registered_many(struct list_head *head)
5957
{
5958
	struct net_device *dev, *tmp;
5959
	LIST_HEAD(close_head);
5960

5961 5962 5963
	BUG_ON(dev_boot_phase);
	ASSERT_RTNL();

5964
	list_for_each_entry_safe(dev, tmp, head, unreg_list) {
5965
		/* Some devices call without registering
5966 5967
		 * for initialization unwind. Remove those
		 * devices and proceed with the remaining.
5968 5969
		 */
		if (dev->reg_state == NETREG_UNINITIALIZED) {
5970 5971
			pr_debug("unregister_netdevice: device %s/%p never was registered\n",
				 dev->name, dev);
5972

5973
			WARN_ON(1);
5974 5975
			list_del(&dev->unreg_list);
			continue;
5976
		}
5977
		dev->dismantle = true;
5978
		BUG_ON(dev->reg_state != NETREG_REGISTERED);
5979
	}
5980

5981
	/* If device is running, close it first. */
5982 5983
	list_for_each_entry(dev, head, unreg_list)
		list_add_tail(&dev->close_list, &close_head);
5984
	dev_close_many(&close_head, true);
5985

5986
	list_for_each_entry(dev, head, unreg_list) {
5987 5988
		/* And unlink it from device chain. */
		unlist_netdevice(dev);
5989

5990 5991
		dev->reg_state = NETREG_UNREGISTERING;
	}
5992 5993 5994

	synchronize_net();

5995
	list_for_each_entry(dev, head, unreg_list) {
5996 5997
		struct sk_buff *skb = NULL;

5998 5999
		/* Shutdown queueing discipline. */
		dev_shutdown(dev);
6000 6001


6002 6003 6004 6005
		/* Notify protocols, that we are about to destroy
		   this device. They should clean all the things.
		*/
		call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6006

6007 6008 6009 6010 6011
		if (!dev->rtnl_link_ops ||
		    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
			skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U,
						     GFP_KERNEL);

6012 6013 6014
		/*
		 *	Flush the unicast and multicast chains
		 */
6015
		dev_uc_flush(dev);
6016
		dev_mc_flush(dev);
6017

6018 6019
		if (dev->netdev_ops->ndo_uninit)
			dev->netdev_ops->ndo_uninit(dev);
6020

6021 6022
		if (skb)
			rtmsg_ifinfo_send(skb, dev, GFP_KERNEL);
6023

J
Jiri Pirko 已提交
6024 6025
		/* Notifier chain MUST detach us all upper devices. */
		WARN_ON(netdev_has_any_upper_dev(dev));
6026

6027 6028
		/* Remove entries from kobject tree */
		netdev_unregister_kobject(dev);
6029 6030 6031 6032
#ifdef CONFIG_XPS
		/* Remove XPS queueing entries */
		netif_reset_xps_queues_gt(dev, 0);
#endif
6033
	}
6034

6035
	synchronize_net();
6036

6037
	list_for_each_entry(dev, head, unreg_list)
6038 6039 6040 6041 6042 6043 6044 6045 6046
		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
6047
	list_del(&single);
6048 6049
}

6050 6051
static netdev_features_t netdev_fix_features(struct net_device *dev,
	netdev_features_t features)
6052
{
6053 6054 6055
	/* Fix illegal checksum combinations */
	if ((features & NETIF_F_HW_CSUM) &&
	    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
6056
		netdev_warn(dev, "mixed HW and IP checksum settings.\n");
6057 6058 6059
		features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
	}

6060
	/* TSO requires that SG is present as well. */
6061
	if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
6062
		netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
6063
		features &= ~NETIF_F_ALL_TSO;
6064 6065
	}

6066 6067 6068 6069 6070 6071 6072 6073 6074 6075 6076 6077 6078
	if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
					!(features & NETIF_F_IP_CSUM)) {
		netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
		features &= ~NETIF_F_TSO;
		features &= ~NETIF_F_TSO_ECN;
	}

	if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
					 !(features & NETIF_F_IPV6_CSUM)) {
		netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
		features &= ~NETIF_F_TSO6;
	}

6079 6080 6081 6082
	/* TSO ECN requires that TSO is present as well. */
	if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
		features &= ~NETIF_F_TSO_ECN;

6083 6084
	/* Software GSO depends on SG. */
	if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
6085
		netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
6086 6087 6088
		features &= ~NETIF_F_GSO;
	}

6089
	/* UFO needs SG and checksumming */
6090
	if (features & NETIF_F_UFO) {
6091 6092 6093 6094
		/* 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))) {
6095
			netdev_dbg(dev,
6096
				"Dropping NETIF_F_UFO since no checksum offload features.\n");
6097 6098 6099 6100
			features &= ~NETIF_F_UFO;
		}

		if (!(features & NETIF_F_SG)) {
6101
			netdev_dbg(dev,
6102
				"Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
6103 6104 6105 6106
			features &= ~NETIF_F_UFO;
		}
	}

J
Jiri Pirko 已提交
6107 6108 6109 6110 6111 6112 6113
#ifdef CONFIG_NET_RX_BUSY_POLL
	if (dev->netdev_ops->ndo_busy_poll)
		features |= NETIF_F_BUSY_POLL;
	else
#endif
		features &= ~NETIF_F_BUSY_POLL;

6114 6115 6116
	return features;
}

6117
int __netdev_update_features(struct net_device *dev)
6118
{
6119
	netdev_features_t features;
6120 6121
	int err = 0;

6122 6123
	ASSERT_RTNL();

6124 6125 6126 6127 6128 6129 6130 6131 6132
	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)
6133
		return 0;
6134

6135 6136
	netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
		&dev->features, &features);
6137 6138 6139 6140

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

6141
	if (unlikely(err < 0)) {
6142
		netdev_err(dev,
6143 6144
			"set_features() failed (%d); wanted %pNF, left %pNF\n",
			err, &features, &dev->features);
6145 6146 6147 6148 6149 6150 6151 6152 6153
		return -1;
	}

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

	return 1;
}

6154 6155 6156 6157 6158 6159 6160 6161
/**
 *	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.
 */
6162 6163 6164 6165
void netdev_update_features(struct net_device *dev)
{
	if (__netdev_update_features(dev))
		netdev_features_change(dev);
6166 6167 6168
}
EXPORT_SYMBOL(netdev_update_features);

6169 6170 6171 6172 6173 6174 6175 6176 6177 6178 6179 6180 6181 6182 6183 6184 6185
/**
 *	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);

6186 6187 6188 6189 6190 6191 6192 6193 6194 6195 6196 6197 6198 6199 6200 6201 6202 6203 6204 6205 6206 6207 6208 6209 6210 6211 6212
/**
 *	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);

6213
#ifdef CONFIG_SYSFS
6214 6215 6216
static int netif_alloc_rx_queues(struct net_device *dev)
{
	unsigned int i, count = dev->num_rx_queues;
T
Tom Herbert 已提交
6217
	struct netdev_rx_queue *rx;
6218
	size_t sz = count * sizeof(*rx);
6219

T
Tom Herbert 已提交
6220
	BUG_ON(count < 1);
6221

6222 6223 6224 6225 6226 6227
	rx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!rx) {
		rx = vzalloc(sz);
		if (!rx)
			return -ENOMEM;
	}
T
Tom Herbert 已提交
6228 6229 6230
	dev->_rx = rx;

	for (i = 0; i < count; i++)
T
Tom Herbert 已提交
6231
		rx[i].dev = dev;
6232 6233
	return 0;
}
T
Tom Herbert 已提交
6234
#endif
6235

C
Changli Gao 已提交
6236 6237 6238 6239 6240 6241 6242
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;
6243
	netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
C
Changli Gao 已提交
6244
	queue->dev = dev;
T
Tom Herbert 已提交
6245 6246 6247
#ifdef CONFIG_BQL
	dql_init(&queue->dql, HZ);
#endif
C
Changli Gao 已提交
6248 6249
}

6250 6251
static void netif_free_tx_queues(struct net_device *dev)
{
W
WANG Cong 已提交
6252
	kvfree(dev->_tx);
6253 6254
}

6255 6256 6257 6258
static int netif_alloc_netdev_queues(struct net_device *dev)
{
	unsigned int count = dev->num_tx_queues;
	struct netdev_queue *tx;
6259
	size_t sz = count * sizeof(*tx);
6260

6261
	BUG_ON(count < 1 || count > 0xffff);
6262

6263 6264 6265 6266 6267 6268
	tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!tx) {
		tx = vzalloc(sz);
		if (!tx)
			return -ENOMEM;
	}
6269
	dev->_tx = tx;
T
Tom Herbert 已提交
6270

6271 6272
	netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
	spin_lock_init(&dev->tx_global_lock);
C
Changli Gao 已提交
6273 6274

	return 0;
6275 6276
}

L
Linus Torvalds 已提交
6277 6278 6279 6280 6281 6282 6283 6284 6285 6286 6287 6288 6289 6290 6291 6292 6293 6294 6295 6296
/**
 *	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;
6297
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
6298 6299 6300 6301

	BUG_ON(dev_boot_phase);
	ASSERT_RTNL();

6302 6303
	might_sleep();

L
Linus Torvalds 已提交
6304 6305
	/* When net_device's are persistent, this will be fatal. */
	BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
6306
	BUG_ON(!net);
L
Linus Torvalds 已提交
6307

6308
	spin_lock_init(&dev->addr_list_lock);
6309
	netdev_set_addr_lockdep_class(dev);
L
Linus Torvalds 已提交
6310 6311 6312

	dev->iflink = -1;

6313
	ret = dev_get_valid_name(net, dev, dev->name);
6314 6315 6316
	if (ret < 0)
		goto out;

L
Linus Torvalds 已提交
6317
	/* Init, if this function is available */
6318 6319
	if (dev->netdev_ops->ndo_init) {
		ret = dev->netdev_ops->ndo_init(dev);
L
Linus Torvalds 已提交
6320 6321 6322
		if (ret) {
			if (ret > 0)
				ret = -EIO;
6323
			goto out;
L
Linus Torvalds 已提交
6324 6325
		}
	}
6326

6327 6328
	if (((dev->hw_features | dev->features) &
	     NETIF_F_HW_VLAN_CTAG_FILTER) &&
6329 6330 6331 6332 6333 6334 6335
	    (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
	     !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
		netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
		ret = -EINVAL;
		goto err_uninit;
	}

6336 6337 6338 6339 6340 6341
	ret = -EBUSY;
	if (!dev->ifindex)
		dev->ifindex = dev_new_index(net);
	else if (__dev_get_by_index(net, dev->ifindex))
		goto err_uninit;

L
Linus Torvalds 已提交
6342 6343 6344
	if (dev->iflink == -1)
		dev->iflink = dev->ifindex;

6345 6346 6347 6348
	/* Transfer changeable features to wanted_features and enable
	 * software offloads (GSO and GRO).
	 */
	dev->hw_features |= NETIF_F_SOFT_FEATURES;
6349 6350
	dev->features |= NETIF_F_SOFT_FEATURES;
	dev->wanted_features = dev->features & dev->hw_features;
L
Linus Torvalds 已提交
6351

6352 6353
	if (!(dev->flags & IFF_LOOPBACK)) {
		dev->hw_features |= NETIF_F_NOCACHE_COPY;
6354 6355
	}

6356
	/* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
6357
	 */
6358
	dev->vlan_features |= NETIF_F_HIGHDMA;
6359

6360 6361 6362 6363
	/* Make NETIF_F_SG inheritable to tunnel devices.
	 */
	dev->hw_enc_features |= NETIF_F_SG;

S
Simon Horman 已提交
6364 6365 6366 6367
	/* Make NETIF_F_SG inheritable to MPLS.
	 */
	dev->mpls_features |= NETIF_F_SG;

6368 6369 6370 6371 6372
	ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
	ret = notifier_to_errno(ret);
	if (ret)
		goto err_uninit;

6373
	ret = netdev_register_kobject(dev);
6374
	if (ret)
6375
		goto err_uninit;
6376 6377
	dev->reg_state = NETREG_REGISTERED;

6378
	__netdev_update_features(dev);
6379

L
Linus Torvalds 已提交
6380 6381 6382 6383 6384 6385 6386
	/*
	 *	Default initial state at registry is that the
	 *	device is present.
	 */

	set_bit(__LINK_STATE_PRESENT, &dev->state);

6387 6388
	linkwatch_init_dev(dev);

L
Linus Torvalds 已提交
6389 6390
	dev_init_scheduler(dev);
	dev_hold(dev);
6391
	list_netdevice(dev);
6392
	add_device_randomness(dev->dev_addr, dev->addr_len);
L
Linus Torvalds 已提交
6393

6394 6395 6396 6397 6398 6399 6400
	/* If the device has permanent device address, driver should
	 * set dev_addr and also addr_assign_type should be set to
	 * NET_ADDR_PERM (default value).
	 */
	if (dev->addr_assign_type == NET_ADDR_PERM)
		memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);

L
Linus Torvalds 已提交
6401
	/* Notify protocols, that a new device appeared. */
6402
	ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
6403
	ret = notifier_to_errno(ret);
6404 6405 6406 6407
	if (ret) {
		rollback_registered(dev);
		dev->reg_state = NETREG_UNREGISTERED;
	}
6408 6409 6410 6411
	/*
	 *	Prevent userspace races by waiting until the network
	 *	device is fully setup before sending notifications.
	 */
6412 6413
	if (!dev->rtnl_link_ops ||
	    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
6414
		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
L
Linus Torvalds 已提交
6415 6416 6417

out:
	return ret;
6418 6419

err_uninit:
6420 6421
	if (dev->netdev_ops->ndo_uninit)
		dev->netdev_ops->ndo_uninit(dev);
6422
	goto out;
L
Linus Torvalds 已提交
6423
}
E
Eric Dumazet 已提交
6424
EXPORT_SYMBOL(register_netdevice);
L
Linus Torvalds 已提交
6425

6426 6427 6428 6429 6430 6431 6432 6433 6434 6435 6436 6437 6438 6439 6440 6441 6442 6443 6444 6445 6446 6447 6448 6449 6450 6451 6452 6453 6454 6455 6456
/**
 *	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
6457 6458 6459 6460 6461
	/* Note : We dont allocate pcpu_refcnt for dummy devices,
	 * because users of this 'device' dont need to change
	 * its refcount.
	 */

6462 6463 6464 6465 6466
	return 0;
}
EXPORT_SYMBOL_GPL(init_dummy_netdev);


L
Linus Torvalds 已提交
6467 6468 6469 6470 6471 6472 6473 6474 6475
/**
 *	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.
 *
6476
 *	This is a wrapper around register_netdevice that takes the rtnl semaphore
L
Linus Torvalds 已提交
6477 6478 6479 6480 6481 6482 6483 6484 6485 6486 6487 6488 6489 6490
 *	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
6491 6492 6493 6494 6495 6496 6497 6498 6499 6500
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);

6501
/**
L
Linus Torvalds 已提交
6502
 * netdev_wait_allrefs - wait until all references are gone.
6503
 * @dev: target net_device
L
Linus Torvalds 已提交
6504 6505 6506 6507 6508 6509 6510
 *
 * 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
6511
 * call dev_put.
L
Linus Torvalds 已提交
6512 6513 6514 6515
 */
static void netdev_wait_allrefs(struct net_device *dev)
{
	unsigned long rebroadcast_time, warning_time;
E
Eric Dumazet 已提交
6516
	int refcnt;
L
Linus Torvalds 已提交
6517

6518 6519
	linkwatch_forget_dev(dev);

L
Linus Torvalds 已提交
6520
	rebroadcast_time = warning_time = jiffies;
E
Eric Dumazet 已提交
6521 6522 6523
	refcnt = netdev_refcnt_read(dev);

	while (refcnt != 0) {
L
Linus Torvalds 已提交
6524
		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
6525
			rtnl_lock();
L
Linus Torvalds 已提交
6526 6527

			/* Rebroadcast unregister notification */
6528
			call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
L
Linus Torvalds 已提交
6529

6530
			__rtnl_unlock();
6531
			rcu_barrier();
6532 6533
			rtnl_lock();

6534
			call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
L
Linus Torvalds 已提交
6535 6536 6537 6538 6539 6540 6541 6542 6543 6544 6545
			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();
			}

6546
			__rtnl_unlock();
L
Linus Torvalds 已提交
6547 6548 6549 6550 6551 6552

			rebroadcast_time = jiffies;
		}

		msleep(250);

E
Eric Dumazet 已提交
6553 6554
		refcnt = netdev_refcnt_read(dev);

L
Linus Torvalds 已提交
6555
		if (time_after(jiffies, warning_time + 10 * HZ)) {
6556 6557
			pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
				 dev->name, refcnt);
L
Linus Torvalds 已提交
6558 6559 6560 6561 6562 6563 6564 6565 6566 6567 6568 6569 6570 6571 6572 6573 6574 6575 6576
			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
6577
 * We are invoked by rtnl_unlock().
L
Linus Torvalds 已提交
6578
 * This allows us to deal with problems:
6579
 * 1) We can delete sysfs objects which invoke hotplug
L
Linus Torvalds 已提交
6580 6581 6582
 *    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
6583 6584 6585
 *
 * 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
6586 6587 6588
 */
void netdev_run_todo(void)
{
6589
	struct list_head list;
L
Linus Torvalds 已提交
6590 6591

	/* Snapshot list, allow later requests */
6592
	list_replace_init(&net_todo_list, &list);
H
Herbert Xu 已提交
6593 6594

	__rtnl_unlock();
6595

6596 6597

	/* Wait for rcu callbacks to finish before next phase */
6598 6599 6600
	if (!list_empty(&list))
		rcu_barrier();

L
Linus Torvalds 已提交
6601 6602
	while (!list_empty(&list)) {
		struct net_device *dev
6603
			= list_first_entry(&list, struct net_device, todo_list);
L
Linus Torvalds 已提交
6604 6605
		list_del(&dev->todo_list);

6606
		rtnl_lock();
6607
		call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6608
		__rtnl_unlock();
6609

6610
		if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
6611
			pr_err("network todo '%s' but state %d\n",
6612 6613 6614 6615
			       dev->name, dev->reg_state);
			dump_stack();
			continue;
		}
L
Linus Torvalds 已提交
6616

6617
		dev->reg_state = NETREG_UNREGISTERED;
L
Linus Torvalds 已提交
6618

6619
		on_each_cpu(flush_backlog, dev, 1);
6620

6621
		netdev_wait_allrefs(dev);
L
Linus Torvalds 已提交
6622

6623
		/* paranoia */
E
Eric Dumazet 已提交
6624
		BUG_ON(netdev_refcnt_read(dev));
6625 6626
		BUG_ON(!list_empty(&dev->ptype_all));
		BUG_ON(!list_empty(&dev->ptype_specific));
6627 6628
		WARN_ON(rcu_access_pointer(dev->ip_ptr));
		WARN_ON(rcu_access_pointer(dev->ip6_ptr));
6629
		WARN_ON(dev->dn_ptr);
L
Linus Torvalds 已提交
6630

6631 6632
		if (dev->destructor)
			dev->destructor(dev);
6633

6634 6635 6636 6637 6638 6639
		/* Report a network device has been unregistered */
		rtnl_lock();
		dev_net(dev)->dev_unreg_count--;
		__rtnl_unlock();
		wake_up(&netdev_unregistering_wq);

6640 6641
		/* Free network device */
		kobject_put(&dev->dev.kobj);
L
Linus Torvalds 已提交
6642 6643 6644
	}
}

6645 6646 6647
/* Convert net_device_stats to rtnl_link_stats64.  They have the same
 * fields in the same order, with only the type differing.
 */
6648 6649
void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
			     const struct net_device_stats *netdev_stats)
6650 6651
{
#if BITS_PER_LONG == 64
6652 6653
	BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
	memcpy(stats64, netdev_stats, sizeof(*stats64));
6654 6655 6656 6657 6658 6659 6660 6661 6662 6663 6664
#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
}
6665
EXPORT_SYMBOL(netdev_stats_to_stats64);
6666

6667 6668 6669
/**
 *	dev_get_stats	- get network device statistics
 *	@dev: device to get statistics from
6670
 *	@storage: place to store stats
6671
 *
6672 6673 6674 6675
 *	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.
6676
 */
6677 6678
struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
					struct rtnl_link_stats64 *storage)
6679
{
6680 6681
	const struct net_device_ops *ops = dev->netdev_ops;

6682 6683
	if (ops->ndo_get_stats64) {
		memset(storage, 0, sizeof(*storage));
6684 6685
		ops->ndo_get_stats64(dev, storage);
	} else if (ops->ndo_get_stats) {
6686
		netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
6687 6688
	} else {
		netdev_stats_to_stats64(storage, &dev->stats);
6689
	}
6690
	storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
6691
	storage->tx_dropped += atomic_long_read(&dev->tx_dropped);
6692
	return storage;
R
Rusty Russell 已提交
6693
}
6694
EXPORT_SYMBOL(dev_get_stats);
R
Rusty Russell 已提交
6695

6696
struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
6697
{
6698
	struct netdev_queue *queue = dev_ingress_queue(dev);
6699

6700 6701 6702 6703 6704 6705 6706
#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);
E
Eric Dumazet 已提交
6707
	RCU_INIT_POINTER(queue->qdisc, &noop_qdisc);
6708 6709 6710 6711
	queue->qdisc_sleeping = &noop_qdisc;
	rcu_assign_pointer(dev->ingress_queue, queue);
#endif
	return queue;
6712 6713
}

6714 6715
static const struct ethtool_ops default_ethtool_ops;

6716 6717 6718 6719 6720 6721 6722 6723
void netdev_set_default_ethtool_ops(struct net_device *dev,
				    const struct ethtool_ops *ops)
{
	if (dev->ethtool_ops == &default_ethtool_ops)
		dev->ethtool_ops = ops;
}
EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);

6724 6725 6726 6727
void netdev_freemem(struct net_device *dev)
{
	char *addr = (char *)dev - dev->padded;

W
WANG Cong 已提交
6728
	kvfree(addr);
6729 6730
}

L
Linus Torvalds 已提交
6731
/**
T
Tom Herbert 已提交
6732
 *	alloc_netdev_mqs - allocate network device
6733 6734 6735 6736 6737 6738
 *	@sizeof_priv:		size of private data to allocate space for
 *	@name:			device name format string
 *	@name_assign_type: 	origin of device name
 *	@setup:			callback to initialize device
 *	@txqs:			the number of TX subqueues to allocate
 *	@rxqs:			the number of RX subqueues to allocate
L
Linus Torvalds 已提交
6739 6740
 *
 *	Allocates a struct net_device with private data area for driver use
L
Li Zhong 已提交
6741
 *	and performs basic initialization.  Also allocates subqueue structs
T
Tom Herbert 已提交
6742
 *	for each queue on the device.
L
Linus Torvalds 已提交
6743
 */
T
Tom Herbert 已提交
6744
struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
6745
		unsigned char name_assign_type,
T
Tom Herbert 已提交
6746 6747
		void (*setup)(struct net_device *),
		unsigned int txqs, unsigned int rxqs)
L
Linus Torvalds 已提交
6748 6749
{
	struct net_device *dev;
6750
	size_t alloc_size;
6751
	struct net_device *p;
L
Linus Torvalds 已提交
6752

6753 6754
	BUG_ON(strlen(name) >= sizeof(dev->name));

T
Tom Herbert 已提交
6755
	if (txqs < 1) {
6756
		pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
6757 6758 6759
		return NULL;
	}

6760
#ifdef CONFIG_SYSFS
T
Tom Herbert 已提交
6761
	if (rxqs < 1) {
6762
		pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
T
Tom Herbert 已提交
6763 6764 6765 6766
		return NULL;
	}
#endif

6767
	alloc_size = sizeof(struct net_device);
6768 6769
	if (sizeof_priv) {
		/* ensure 32-byte alignment of private area */
6770
		alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
6771 6772 6773
		alloc_size += sizeof_priv;
	}
	/* ensure 32-byte alignment of whole construct */
6774
	alloc_size += NETDEV_ALIGN - 1;
L
Linus Torvalds 已提交
6775

6776 6777 6778
	p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!p)
		p = vzalloc(alloc_size);
6779
	if (!p)
L
Linus Torvalds 已提交
6780 6781
		return NULL;

6782
	dev = PTR_ALIGN(p, NETDEV_ALIGN);
L
Linus Torvalds 已提交
6783
	dev->padded = (char *)dev - (char *)p;
6784

E
Eric Dumazet 已提交
6785 6786
	dev->pcpu_refcnt = alloc_percpu(int);
	if (!dev->pcpu_refcnt)
6787
		goto free_dev;
6788 6789

	if (dev_addr_init(dev))
E
Eric Dumazet 已提交
6790
		goto free_pcpu;
6791

6792
	dev_mc_init(dev);
6793
	dev_uc_init(dev);
J
Jiri Pirko 已提交
6794

6795
	dev_net_set(dev, &init_net);
L
Linus Torvalds 已提交
6796

6797
	dev->gso_max_size = GSO_MAX_SIZE;
6798
	dev->gso_max_segs = GSO_MAX_SEGS;
6799
	dev->gso_min_segs = 0;
6800 6801 6802

	INIT_LIST_HEAD(&dev->napi_list);
	INIT_LIST_HEAD(&dev->unreg_list);
6803
	INIT_LIST_HEAD(&dev->close_list);
6804
	INIT_LIST_HEAD(&dev->link_watch_list);
6805 6806 6807 6808
	INIT_LIST_HEAD(&dev->adj_list.upper);
	INIT_LIST_HEAD(&dev->adj_list.lower);
	INIT_LIST_HEAD(&dev->all_adj_list.upper);
	INIT_LIST_HEAD(&dev->all_adj_list.lower);
6809 6810
	INIT_LIST_HEAD(&dev->ptype_all);
	INIT_LIST_HEAD(&dev->ptype_specific);
6811
	dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM;
6812 6813
	setup(dev);

T
Tom Herbert 已提交
6814 6815
	dev->num_tx_queues = txqs;
	dev->real_num_tx_queues = txqs;
6816
	if (netif_alloc_netdev_queues(dev))
6817
		goto free_all;
6818

6819
#ifdef CONFIG_SYSFS
T
Tom Herbert 已提交
6820 6821
	dev->num_rx_queues = rxqs;
	dev->real_num_rx_queues = rxqs;
T
Tom Herbert 已提交
6822
	if (netif_alloc_rx_queues(dev))
6823
		goto free_all;
E
Eric Dumazet 已提交
6824
#endif
T
Tom Herbert 已提交
6825

L
Linus Torvalds 已提交
6826
	strcpy(dev->name, name);
6827
	dev->name_assign_type = name_assign_type;
6828
	dev->group = INIT_NETDEV_GROUP;
6829 6830
	if (!dev->ethtool_ops)
		dev->ethtool_ops = &default_ethtool_ops;
L
Linus Torvalds 已提交
6831
	return dev;
6832

6833 6834 6835 6836
free_all:
	free_netdev(dev);
	return NULL;

E
Eric Dumazet 已提交
6837 6838
free_pcpu:
	free_percpu(dev->pcpu_refcnt);
6839 6840
free_dev:
	netdev_freemem(dev);
6841
	return NULL;
L
Linus Torvalds 已提交
6842
}
T
Tom Herbert 已提交
6843
EXPORT_SYMBOL(alloc_netdev_mqs);
L
Linus Torvalds 已提交
6844 6845 6846 6847 6848

/**
 *	free_netdev - free network device
 *	@dev: device
 *
6849 6850
 *	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
6851 6852 6853 6854
 *	If this is the last reference then it will be freed.
 */
void free_netdev(struct net_device *dev)
{
6855 6856
	struct napi_struct *p, *n;

6857
	netif_free_tx_queues(dev);
6858
#ifdef CONFIG_SYSFS
6859
	kvfree(dev->_rx);
T
Tom Herbert 已提交
6860
#endif
6861

6862
	kfree(rcu_dereference_protected(dev->ingress_queue, 1));
6863

6864 6865 6866
	/* Flush device addresses */
	dev_addr_flush(dev);

6867 6868 6869
	list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
		netif_napi_del(p);

E
Eric Dumazet 已提交
6870 6871 6872
	free_percpu(dev->pcpu_refcnt);
	dev->pcpu_refcnt = NULL;

S
Stephen Hemminger 已提交
6873
	/*  Compatibility with error handling in drivers */
L
Linus Torvalds 已提交
6874
	if (dev->reg_state == NETREG_UNINITIALIZED) {
6875
		netdev_freemem(dev);
L
Linus Torvalds 已提交
6876 6877 6878 6879 6880 6881
		return;
	}

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

6882 6883
	/* will free via device release */
	put_device(&dev->dev);
L
Linus Torvalds 已提交
6884
}
E
Eric Dumazet 已提交
6885
EXPORT_SYMBOL(free_netdev);
6886

6887 6888 6889 6890 6891 6892
/**
 *	synchronize_net -  Synchronize with packet receive processing
 *
 *	Wait for packets currently being received to be done.
 *	Does not block later packets from starting.
 */
6893
void synchronize_net(void)
L
Linus Torvalds 已提交
6894 6895
{
	might_sleep();
6896 6897 6898 6899
	if (rtnl_is_locked())
		synchronize_rcu_expedited();
	else
		synchronize_rcu();
L
Linus Torvalds 已提交
6900
}
E
Eric Dumazet 已提交
6901
EXPORT_SYMBOL(synchronize_net);
L
Linus Torvalds 已提交
6902 6903

/**
6904
 *	unregister_netdevice_queue - remove device from the kernel
L
Linus Torvalds 已提交
6905
 *	@dev: device
6906
 *	@head: list
6907
 *
L
Linus Torvalds 已提交
6908
 *	This function shuts down a device interface and removes it
6909
 *	from the kernel tables.
6910
 *	If head not NULL, device is queued to be unregistered later.
L
Linus Torvalds 已提交
6911 6912 6913 6914 6915
 *
 *	Callers must hold the rtnl semaphore.  You may want
 *	unregister_netdev() instead of this.
 */

6916
void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
L
Linus Torvalds 已提交
6917
{
6918 6919
	ASSERT_RTNL();

6920
	if (head) {
6921
		list_move_tail(&dev->unreg_list, head);
6922 6923 6924 6925 6926
	} else {
		rollback_registered(dev);
		/* Finish processing unregister after unlock */
		net_set_todo(dev);
	}
L
Linus Torvalds 已提交
6927
}
6928
EXPORT_SYMBOL(unregister_netdevice_queue);
L
Linus Torvalds 已提交
6929

6930 6931 6932
/**
 *	unregister_netdevice_many - unregister many devices
 *	@head: list of devices
6933 6934 6935
 *
 *  Note: As most callers use a stack allocated list_head,
 *  we force a list_del() to make sure stack wont be corrupted later.
6936 6937 6938 6939 6940 6941 6942 6943 6944
 */
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);
6945
		list_del(head);
6946 6947
	}
}
6948
EXPORT_SYMBOL(unregister_netdevice_many);
6949

L
Linus Torvalds 已提交
6950 6951 6952 6953 6954
/**
 *	unregister_netdev - remove device from the kernel
 *	@dev: device
 *
 *	This function shuts down a device interface and removes it
6955
 *	from the kernel tables.
L
Linus Torvalds 已提交
6956 6957 6958 6959 6960 6961 6962 6963 6964 6965 6966 6967 6968
 *
 *	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);

6969 6970 6971 6972 6973 6974 6975 6976 6977 6978 6979 6980 6981 6982 6983 6984 6985 6986 6987 6988 6989 6990 6991 6992 6993 6994 6995 6996 6997 6998 6999
/**
 *	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 */
	if (dev->reg_state != NETREG_REGISTERED)
		goto out;

	/* Get out if there is nothing todo */
	err = 0;
7000
	if (net_eq(dev_net(dev), net))
7001 7002 7003 7004 7005 7006
		goto out;

	/* Pick the destination device name, and ensure
	 * we can use it in the destination network namespace.
	 */
	err = -EEXIST;
7007
	if (__dev_get_by_name(net, dev->name)) {
7008 7009 7010
		/* We get here if we can't use the current device name */
		if (!pat)
			goto out;
7011
		if (dev_get_valid_name(net, dev, pat) < 0)
7012 7013 7014 7015 7016 7017 7018 7019
			goto out;
	}

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

	/* If device is running close it first. */
7020
	dev_close(dev);
7021 7022 7023 7024 7025 7026 7027 7028 7029 7030 7031 7032

	/* 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.
7033 7034 7035 7036

	   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.
7037 7038
	*/
	call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
7039 7040
	rcu_barrier();
	call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
7041
	rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
7042 7043 7044 7045

	/*
	 *	Flush the unicast and multicast chains
	 */
7046
	dev_uc_flush(dev);
7047
	dev_mc_flush(dev);
7048

7049 7050
	/* Send a netdev-removed uevent to the old namespace */
	kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
7051
	netdev_adjacent_del_links(dev);
7052

7053
	/* Actually switch the network namespace */
7054
	dev_net_set(dev, net);
7055 7056 7057 7058 7059 7060 7061 7062 7063

	/* 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;
	}

7064 7065
	/* Send a netdev-add uevent to the new namespace */
	kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
7066
	netdev_adjacent_add_links(dev);
7067

7068
	/* Fixup kobjects */
7069
	err = device_rename(&dev->dev, dev->name);
7070
	WARN_ON(err);
7071 7072 7073 7074 7075 7076 7077

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

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

7078 7079 7080 7081
	/*
	 *	Prevent userspace races by waiting until the network
	 *	device is fully setup before sending notifications.
	 */
7082
	rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
7083

7084 7085 7086 7087 7088
	synchronize_net();
	err = 0;
out:
	return err;
}
7089
EXPORT_SYMBOL_GPL(dev_change_net_namespace);
7090

L
Linus Torvalds 已提交
7091 7092 7093 7094 7095 7096 7097 7098 7099
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;

7100
	if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
L
Linus Torvalds 已提交
7101 7102 7103 7104 7105 7106 7107 7108 7109 7110 7111 7112 7113 7114 7115 7116
		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. */
7117 7118 7119 7120 7121 7122
	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;
	}
E
Eric Dumazet 已提交
7123 7124 7125 7126 7127 7128 7129 7130 7131 7132 7133 7134 7135 7136
	/* Append NAPI poll list from offline CPU, with one exception :
	 * process_backlog() must be called by cpu owning percpu backlog.
	 * We properly handle process_queue & input_pkt_queue later.
	 */
	while (!list_empty(&oldsd->poll_list)) {
		struct napi_struct *napi = list_first_entry(&oldsd->poll_list,
							    struct napi_struct,
							    poll_list);

		list_del_init(&napi->poll_list);
		if (napi->poll == process_backlog)
			napi->state = 0;
		else
			____napi_schedule(sd, napi);
7137
	}
L
Linus Torvalds 已提交
7138 7139 7140 7141 7142

	raise_softirq_irqoff(NET_TX_SOFTIRQ);
	local_irq_enable();

	/* Process offline CPU's input_pkt_queue */
7143
	while ((skb = __skb_dequeue(&oldsd->process_queue))) {
7144
		netif_rx_ni(skb);
7145
		input_queue_head_incr(oldsd);
T
Tom Herbert 已提交
7146
	}
E
Eric Dumazet 已提交
7147
	while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
7148
		netif_rx_ni(skb);
7149 7150
		input_queue_head_incr(oldsd);
	}
L
Linus Torvalds 已提交
7151 7152 7153 7154 7155

	return NOTIFY_OK;
}


7156
/**
7157 7158 7159 7160
 *	netdev_increment_features - increment feature set by one
 *	@all: current feature set
 *	@one: new feature set
 *	@mask: mask feature set
7161 7162
 *
 *	Computes a new feature set after adding a device with feature set
7163 7164
 *	@one to the master device with current feature set @all.  Will not
 *	enable anything that is off in @mask. Returns the new feature set.
7165
 */
7166 7167
netdev_features_t netdev_increment_features(netdev_features_t all,
	netdev_features_t one, netdev_features_t mask)
7168
{
7169 7170 7171
	if (mask & NETIF_F_GEN_CSUM)
		mask |= NETIF_F_ALL_CSUM;
	mask |= NETIF_F_VLAN_CHALLENGED;
7172

7173 7174
	all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
	all &= one | ~NETIF_F_ALL_FOR_ALL;
7175

7176 7177 7178
	/* If one device supports hw checksumming, set for all. */
	if (all & NETIF_F_GEN_CSUM)
		all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
7179 7180 7181

	return all;
}
7182
EXPORT_SYMBOL(netdev_increment_features);
7183

7184
static struct hlist_head * __net_init netdev_create_hash(void)
7185 7186 7187 7188 7189 7190 7191 7192 7193 7194 7195 7196
{
	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;
}

7197
/* Initialize per network namespace state */
7198
static int __net_init netdev_init(struct net *net)
7199
{
7200 7201
	if (net != &init_net)
		INIT_LIST_HEAD(&net->dev_base_head);
7202

7203 7204 7205
	net->dev_name_head = netdev_create_hash();
	if (net->dev_name_head == NULL)
		goto err_name;
7206

7207 7208 7209
	net->dev_index_head = netdev_create_hash();
	if (net->dev_index_head == NULL)
		goto err_idx;
7210 7211

	return 0;
7212 7213 7214 7215 7216

err_idx:
	kfree(net->dev_name_head);
err_name:
	return -ENOMEM;
7217 7218
}

7219 7220 7221 7222 7223 7224
/**
 *	netdev_drivername - network driver for the device
 *	@dev: network device
 *
 *	Determine network driver for device.
 */
7225
const char *netdev_drivername(const struct net_device *dev)
7226
{
7227 7228
	const struct device_driver *driver;
	const struct device *parent;
7229
	const char *empty = "";
7230 7231 7232

	parent = dev->dev.parent;
	if (!parent)
7233
		return empty;
7234 7235 7236

	driver = parent->driver;
	if (driver && driver->name)
7237 7238
		return driver->name;
	return empty;
7239 7240
}

7241 7242
static void __netdev_printk(const char *level, const struct net_device *dev,
			    struct va_format *vaf)
7243
{
7244
	if (dev && dev->dev.parent) {
7245 7246 7247 7248 7249 7250 7251
		dev_printk_emit(level[1] - '0',
				dev->dev.parent,
				"%s %s %s%s: %pV",
				dev_driver_string(dev->dev.parent),
				dev_name(dev->dev.parent),
				netdev_name(dev), netdev_reg_state(dev),
				vaf);
7252
	} else if (dev) {
7253 7254
		printk("%s%s%s: %pV",
		       level, netdev_name(dev), netdev_reg_state(dev), vaf);
7255
	} else {
7256
		printk("%s(NULL net_device): %pV", level, vaf);
7257
	}
7258 7259
}

7260 7261
void netdev_printk(const char *level, const struct net_device *dev,
		   const char *format, ...)
7262 7263 7264 7265 7266 7267 7268 7269 7270
{
	struct va_format vaf;
	va_list args;

	va_start(args, format);

	vaf.fmt = format;
	vaf.va = &args;

7271
	__netdev_printk(level, dev, &vaf);
7272

7273 7274 7275 7276 7277
	va_end(args);
}
EXPORT_SYMBOL(netdev_printk);

#define define_netdev_printk_level(func, level)			\
7278
void func(const struct net_device *dev, const char *fmt, ...)	\
7279 7280 7281 7282 7283 7284 7285 7286 7287
{								\
	struct va_format vaf;					\
	va_list args;						\
								\
	va_start(args, fmt);					\
								\
	vaf.fmt = fmt;						\
	vaf.va = &args;						\
								\
7288
	__netdev_printk(level, dev, &vaf);			\
7289
								\
7290 7291 7292 7293 7294 7295 7296 7297 7298 7299 7300 7301
	va_end(args);						\
}								\
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);

7302
static void __net_exit netdev_exit(struct net *net)
7303 7304 7305 7306 7307
{
	kfree(net->dev_name_head);
	kfree(net->dev_index_head);
}

7308
static struct pernet_operations __net_initdata netdev_net_ops = {
7309 7310 7311 7312
	.init = netdev_init,
	.exit = netdev_exit,
};

7313
static void __net_exit default_device_exit(struct net *net)
7314
{
7315
	struct net_device *dev, *aux;
7316
	/*
7317
	 * Push all migratable network devices back to the
7318 7319 7320
	 * initial network namespace
	 */
	rtnl_lock();
7321
	for_each_netdev_safe(net, dev, aux) {
7322
		int err;
7323
		char fb_name[IFNAMSIZ];
7324 7325 7326 7327 7328

		/* Ignore unmoveable devices (i.e. loopback) */
		if (dev->features & NETIF_F_NETNS_LOCAL)
			continue;

7329 7330 7331
		/* Leave virtual devices for the generic cleanup */
		if (dev->rtnl_link_ops)
			continue;
7332

L
Lucas De Marchi 已提交
7333
		/* Push remaining network devices to init_net */
7334 7335
		snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
		err = dev_change_net_namespace(dev, &init_net, fb_name);
7336
		if (err) {
7337 7338
			pr_emerg("%s: failed to move %s to init_net: %d\n",
				 __func__, dev->name, err);
7339
			BUG();
7340 7341 7342 7343 7344
		}
	}
	rtnl_unlock();
}

7345 7346 7347 7348 7349 7350 7351
static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)
{
	/* Return with the rtnl_lock held when there are no network
	 * devices unregistering in any network namespace in net_list.
	 */
	struct net *net;
	bool unregistering;
7352
	DEFINE_WAIT_FUNC(wait, woken_wake_function);
7353

7354
	add_wait_queue(&netdev_unregistering_wq, &wait);
7355 7356 7357 7358 7359 7360 7361 7362 7363 7364 7365 7366
	for (;;) {
		unregistering = false;
		rtnl_lock();
		list_for_each_entry(net, net_list, exit_list) {
			if (net->dev_unreg_count > 0) {
				unregistering = true;
				break;
			}
		}
		if (!unregistering)
			break;
		__rtnl_unlock();
7367 7368

		wait_woken(&wait, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
7369
	}
7370
	remove_wait_queue(&netdev_unregistering_wq, &wait);
7371 7372
}

7373 7374 7375
static void __net_exit default_device_exit_batch(struct list_head *net_list)
{
	/* At exit all network devices most be removed from a network
7376
	 * namespace.  Do this in the reverse order of registration.
7377 7378 7379 7380 7381 7382 7383
	 * 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);

7384 7385 7386 7387 7388 7389 7390 7391 7392 7393 7394 7395
	/* To prevent network device cleanup code from dereferencing
	 * loopback devices or network devices that have been freed
	 * wait here for all pending unregistrations to complete,
	 * before unregistring the loopback device and allowing the
	 * network namespace be freed.
	 *
	 * The netdev todo list containing all network devices
	 * unregistrations that happen in default_device_exit_batch
	 * will run in the rtnl_unlock() at the end of
	 * default_device_exit_batch.
	 */
	rtnl_lock_unregistering(net_list);
7396 7397
	list_for_each_entry(net, net_list, exit_list) {
		for_each_netdev_reverse(net, dev) {
7398
			if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink)
7399 7400 7401 7402 7403 7404 7405 7406 7407
				dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
			else
				unregister_netdevice_queue(dev, &dev_kill_list);
		}
	}
	unregister_netdevice_many(&dev_kill_list);
	rtnl_unlock();
}

7408
static struct pernet_operations __net_initdata default_device_ops = {
7409
	.exit = default_device_exit,
7410
	.exit_batch = default_device_exit_batch,
7411 7412
};

L
Linus Torvalds 已提交
7413 7414 7415 7416 7417 7418 7419 7420 7421 7422 7423 7424 7425 7426 7427 7428 7429 7430 7431 7432
/*
 *	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;

7433
	if (netdev_kobject_init())
L
Linus Torvalds 已提交
7434 7435 7436
		goto out;

	INIT_LIST_HEAD(&ptype_all);
7437
	for (i = 0; i < PTYPE_HASH_SIZE; i++)
L
Linus Torvalds 已提交
7438 7439
		INIT_LIST_HEAD(&ptype_base[i]);

7440 7441
	INIT_LIST_HEAD(&offload_base);

7442 7443
	if (register_pernet_subsys(&netdev_net_ops))
		goto out;
L
Linus Torvalds 已提交
7444 7445 7446 7447 7448

	/*
	 *	Initialise the packet receive queues.
	 */

7449
	for_each_possible_cpu(i) {
E
Eric Dumazet 已提交
7450
		struct softnet_data *sd = &per_cpu(softnet_data, i);
L
Linus Torvalds 已提交
7451

E
Eric Dumazet 已提交
7452
		skb_queue_head_init(&sd->input_pkt_queue);
7453
		skb_queue_head_init(&sd->process_queue);
E
Eric Dumazet 已提交
7454
		INIT_LIST_HEAD(&sd->poll_list);
7455
		sd->output_queue_tailp = &sd->output_queue;
E
Eric Dumazet 已提交
7456
#ifdef CONFIG_RPS
E
Eric Dumazet 已提交
7457 7458 7459
		sd->csd.func = rps_trigger_softirq;
		sd->csd.info = sd;
		sd->cpu = i;
7460
#endif
T
Tom Herbert 已提交
7461

E
Eric Dumazet 已提交
7462 7463
		sd->backlog.poll = process_backlog;
		sd->backlog.weight = weight_p;
L
Linus Torvalds 已提交
7464 7465 7466 7467
	}

	dev_boot_phase = 0;

7468 7469 7470 7471 7472 7473 7474 7475 7476 7477 7478 7479 7480 7481 7482
	/* 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;

7483 7484
	open_softirq(NET_TX_SOFTIRQ, net_tx_action);
	open_softirq(NET_RX_SOFTIRQ, net_rx_action);
L
Linus Torvalds 已提交
7485 7486 7487 7488 7489 7490 7491 7492 7493

	hotcpu_notifier(dev_cpu_callback, 0);
	dst_init();
	rc = 0;
out:
	return rc;
}

subsys_initcall(net_dev_init);