dev.c 186.8 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

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

662 663 664 665 666 667 668 669 670 671 672 673 674
/**
 *	dev_get_iflink	- get 'iflink' value of a interface
 *	@dev: targeted interface
 *
 *	Indicates the ifindex the interface is linked to.
 *	Physical interfaces have the same 'ifindex' and 'iflink' values.
 */

int dev_get_iflink(const struct net_device *dev)
{
	if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink)
		return dev->netdev_ops->ndo_get_iflink(dev);

675 676 677 678
	/* If dev->rtnl_link_ops is set, it's a virtual interface. */
	if (dev->rtnl_link_ops)
		return 0;

679
	return dev->ifindex;
680 681 682
}
EXPORT_SYMBOL(dev_get_iflink);

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/**
 *	__dev_get_by_name	- find a device by its name
685
 *	@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.
 */

695
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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700
	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;
}
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EXPORT_SYMBOL(__dev_get_by_name);
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708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724
/**
 *	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);

725
	hlist_for_each_entry_rcu(dev, head, name_hlist)
726 727 728 729 730 731 732
		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
735
 *	@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.
 */

745
struct net_device *dev_get_by_name(struct net *net, const char *name)
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{
	struct net_device *dev;

749 750
	rcu_read_lock();
	dev = dev_get_by_name_rcu(net, name);
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	if (dev)
		dev_hold(dev);
753
	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
760
 *	@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.
 */

770
struct net_device *__dev_get_by_index(struct net *net, int ifindex)
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{
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	struct net_device *dev;
	struct hlist_head *head = dev_index_hash(net, ifindex);
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774

775
	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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783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798
/**
 *	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);

799
	hlist_for_each_entry_rcu(dev, head, index_hlist)
800 801 802 803 804 805 806
		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
810
 *	@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.
 */

819
struct net_device *dev_get_by_index(struct net *net, int ifindex)
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{
	struct net_device *dev;

823 824
	rcu_read_lock();
	dev = dev_get_by_index_rcu(net, ifindex);
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	if (dev)
		dev_hold(dev);
827
	rcu_read_unlock();
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	return dev;
}
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EXPORT_SYMBOL(dev_get_by_index);
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832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865
/**
 *	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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/**
867
 *	dev_getbyhwaddr_rcu - find a device by its hardware address
868
 *	@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.
875
 *	The returned device has not had its ref count increased
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 *	and the caller must therefore be careful about locking
 *
 */

880 881
struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
				       const char *ha)
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{
	struct net_device *dev;

885
	for_each_netdev_rcu(net, dev)
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		if (dev->type == type &&
		    !memcmp(dev->dev_addr, ha, dev->addr_len))
888 889 890
			return dev;

	return NULL;
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}
892
EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
893

894
struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
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{
	struct net_device *dev;

898
	ASSERT_RTNL();
899
	for_each_netdev(net, dev)
900
		if (dev->type == type)
901 902 903
			return dev;

	return NULL;
904 905 906
}
EXPORT_SYMBOL(__dev_getfirstbyhwtype);

907
struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
908
{
909
	struct net_device *dev, *ret = NULL;
910

911 912 913 914 915 916 917 918 919
	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);

/**
924
 *	__dev_get_by_flags - find any device with given flags
925
 *	@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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 *	is not found or a pointer to the device. Must be called inside
931
 *	rtnl_lock(), and result refcount is unchanged.
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 */

934 935
struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags,
				      unsigned short mask)
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{
937
	struct net_device *dev, *ret;
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939 940
	ASSERT_RTNL();

941
	ret = NULL;
942
	for_each_netdev(net, dev) {
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		if (((dev->flags ^ if_flags) & mask) == 0) {
944
			ret = dev;
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			break;
		}
	}
948
	return ret;
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}
950
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
957 958
 *	to allow sysfs to work.  We also disallow any kind of
 *	whitespace.
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 */
960
bool dev_valid_name(const char *name)
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{
962
	if (*name == '\0')
963
		return false;
964
	if (strlen(name) >= IFNAMSIZ)
965
		return false;
966
	if (!strcmp(name, ".") || !strcmp(name, ".."))
967
		return false;
968 969

	while (*name) {
970
		if (*name == '/' || *name == ':' || isspace(*name))
971
			return false;
972 973
		name++;
	}
974
	return true;
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}
E
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EXPORT_SYMBOL(dev_valid_name);
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/**
979 980
 *	__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
982
 *	@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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 */

993
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 */
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		inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
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		if (!inuse)
			return -ENOMEM;

1016
		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 */
1023
			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);
	}

1032 1033
	if (buf != name)
		snprintf(buf, IFNAMSIZ, name, i);
1034
	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;
}

1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063
/**
 *	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;

1064 1065
	BUG_ON(!dev_net(dev));
	net = dev_net(dev);
1066 1067 1068 1069 1070
	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);
1072

1073 1074 1075
static int dev_alloc_name_ns(struct net *net,
			     struct net_device *dev,
			     const char *name)
1076
{
1077 1078
	char buf[IFNAMSIZ];
	int ret;
1079

1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090
	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);
1091

1092 1093 1094
	if (!dev_valid_name(name))
		return -EINVAL;

1095
	if (strchr(name, '%'))
1096
		return dev_alloc_name_ns(net, dev, name);
1097 1098
	else if (__dev_get_by_name(net, name))
		return -EEXIST;
1099 1100
	else if (dev->name != name)
		strlcpy(dev->name, name, IFNAMSIZ);
1101 1102 1103

	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.
 */
1113
int dev_change_name(struct net_device *dev, const char *newname)
L
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{
1115
	unsigned char old_assign_type;
1116
	char oldname[IFNAMSIZ];
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	int err = 0;
1118
	int ret;
1119
	struct net *net;
L
Linus Torvalds 已提交
1120 1121

	ASSERT_RTNL();
1122
	BUG_ON(!dev_net(dev));
L
Linus Torvalds 已提交
1123

1124
	net = dev_net(dev);
L
Linus Torvalds 已提交
1125 1126 1127
	if (dev->flags & IFF_UP)
		return -EBUSY;

1128
	write_seqcount_begin(&devnet_rename_seq);
1129 1130

	if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
1131
		write_seqcount_end(&devnet_rename_seq);
1132
		return 0;
1133
	}
1134

1135 1136
	memcpy(oldname, dev->name, IFNAMSIZ);

1137
	err = dev_get_valid_name(net, dev, newname);
1138
	if (err < 0) {
1139
		write_seqcount_end(&devnet_rename_seq);
1140
		return err;
1141
	}
L
Linus Torvalds 已提交
1142

1143 1144 1145
	if (oldname[0] && !strchr(oldname, '%'))
		netdev_info(dev, "renamed from %s\n", oldname);

1146 1147 1148
	old_assign_type = dev->name_assign_type;
	dev->name_assign_type = NET_NAME_RENAMED;

1149
rollback:
1150 1151 1152
	ret = device_rename(&dev->dev, dev->name);
	if (ret) {
		memcpy(dev->name, oldname, IFNAMSIZ);
1153
		dev->name_assign_type = old_assign_type;
1154
		write_seqcount_end(&devnet_rename_seq);
1155
		return ret;
1156
	}
1157

1158
	write_seqcount_end(&devnet_rename_seq);
1159

1160 1161
	netdev_adjacent_rename_links(dev, oldname);

1162
	write_lock_bh(&dev_base_lock);
1163
	hlist_del_rcu(&dev->name_hlist);
1164 1165 1166 1167 1168 1169
	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));
1170 1171
	write_unlock_bh(&dev_base_lock);

1172
	ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1173 1174 1175
	ret = notifier_to_errno(ret);

	if (ret) {
1176 1177
		/* err >= 0 after dev_alloc_name() or stores the first errno */
		if (err >= 0) {
1178
			err = ret;
1179
			write_seqcount_begin(&devnet_rename_seq);
1180
			memcpy(dev->name, oldname, IFNAMSIZ);
1181
			memcpy(oldname, newname, IFNAMSIZ);
1182 1183
			dev->name_assign_type = old_assign_type;
			old_assign_type = NET_NAME_RENAMED;
1184
			goto rollback;
1185
		} else {
1186
			pr_err("%s: name change rollback failed: %d\n",
1187
			       dev->name, ret);
1188 1189
		}
	}
L
Linus Torvalds 已提交
1190 1191 1192 1193

	return err;
}

1194 1195 1196 1197
/**
 *	dev_set_alias - change ifalias of a device
 *	@dev: device
 *	@alias: name up to IFALIASZ
1198
 *	@len: limit of bytes to copy from info
1199 1200 1201 1202 1203
 *
 *	Set ifalias for a device,
 */
int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
{
1204 1205
	char *new_ifalias;

1206 1207 1208 1209 1210
	ASSERT_RTNL();

	if (len >= IFALIASZ)
		return -EINVAL;

1211
	if (!len) {
1212 1213
		kfree(dev->ifalias);
		dev->ifalias = NULL;
1214 1215 1216
		return 0;
	}

1217 1218
	new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
	if (!new_ifalias)
1219
		return -ENOMEM;
1220
	dev->ifalias = new_ifalias;
1221 1222 1223 1224 1225 1226

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


1227
/**
S
Stephen Hemminger 已提交
1228
 *	netdev_features_change - device changes features
1229 1230 1231 1232 1233 1234
 *	@dev: device to cause notification
 *
 *	Called to indicate a device has changed features.
 */
void netdev_features_change(struct net_device *dev)
{
1235
	call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1236 1237 1238
}
EXPORT_SYMBOL(netdev_features_change);

L
Linus Torvalds 已提交
1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249
/**
 *	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) {
1250 1251 1252 1253 1254
		struct netdev_notifier_change_info change_info;

		change_info.flags_changed = 0;
		call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
					      &change_info.info);
1255
		rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL);
L
Linus Torvalds 已提交
1256 1257
	}
}
E
Eric Dumazet 已提交
1258
EXPORT_SYMBOL(netdev_state_change);
L
Linus Torvalds 已提交
1259

1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270
/**
 * 	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)
1271
{
1272 1273 1274
	rtnl_lock();
	call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
	rtnl_unlock();
1275
}
1276
EXPORT_SYMBOL(netdev_notify_peers);
1277

1278
static int __dev_open(struct net_device *dev)
L
Linus Torvalds 已提交
1279
{
1280
	const struct net_device_ops *ops = dev->netdev_ops;
1281
	int ret;
L
Linus Torvalds 已提交
1282

1283 1284
	ASSERT_RTNL();

L
Linus Torvalds 已提交
1285 1286 1287
	if (!netif_device_present(dev))
		return -ENODEV;

1288 1289 1290 1291
	/* 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
	 */
1292
	netpoll_poll_disable(dev);
1293

1294 1295 1296 1297 1298
	ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
	ret = notifier_to_errno(ret);
	if (ret)
		return ret;

L
Linus Torvalds 已提交
1299
	set_bit(__LINK_STATE_START, &dev->state);
1300

1301 1302
	if (ops->ndo_validate_addr)
		ret = ops->ndo_validate_addr(dev);
1303

1304 1305
	if (!ret && ops->ndo_open)
		ret = ops->ndo_open(dev);
L
Linus Torvalds 已提交
1306

1307
	netpoll_poll_enable(dev);
1308

1309 1310 1311
	if (ret)
		clear_bit(__LINK_STATE_START, &dev->state);
	else {
L
Linus Torvalds 已提交
1312
		dev->flags |= IFF_UP;
1313
		dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
1314
		dev_activate(dev);
1315
		add_device_randomness(dev->dev_addr, dev->addr_len);
L
Linus Torvalds 已提交
1316
	}
1317

L
Linus Torvalds 已提交
1318 1319 1320 1321
	return ret;
}

/**
1322 1323
 *	dev_open	- prepare an interface for use.
 *	@dev:	device to open
L
Linus Torvalds 已提交
1324
 *
1325 1326 1327 1328 1329 1330 1331
 *	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
1332
 */
1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343
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;

1344
	rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1345 1346 1347 1348 1349 1350
	call_netdevice_notifiers(NETDEV_UP, dev);

	return ret;
}
EXPORT_SYMBOL(dev_open);

1351
static int __dev_close_many(struct list_head *head)
L
Linus Torvalds 已提交
1352
{
1353
	struct net_device *dev;
1354

1355
	ASSERT_RTNL();
1356 1357
	might_sleep();

1358
	list_for_each_entry(dev, head, close_list) {
1359
		/* Temporarily disable netpoll until the interface is down */
1360
		netpoll_poll_disable(dev);
1361

1362
		call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
L
Linus Torvalds 已提交
1363

1364
		clear_bit(__LINK_STATE_START, &dev->state);
L
Linus Torvalds 已提交
1365

1366 1367 1368 1369 1370 1371
		/* 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.
		 */
1372
		smp_mb__after_atomic(); /* Commit netif_running(). */
1373
	}
L
Linus Torvalds 已提交
1374

1375
	dev_deactivate_many(head);
1376

1377
	list_for_each_entry(dev, head, close_list) {
1378
		const struct net_device_ops *ops = dev->netdev_ops;
L
Linus Torvalds 已提交
1379

1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390
		/*
		 *	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;
1391
		netpoll_poll_enable(dev);
1392 1393 1394 1395 1396 1397 1398
	}

	return 0;
}

static int __dev_close(struct net_device *dev)
{
1399
	int retval;
1400 1401
	LIST_HEAD(single);

1402
	list_add(&dev->close_list, &single);
1403 1404
	retval = __dev_close_many(&single);
	list_del(&single);
1405

1406
	return retval;
1407 1408
}

1409
int dev_close_many(struct list_head *head, bool unlink)
1410 1411
{
	struct net_device *dev, *tmp;
L
Linus Torvalds 已提交
1412

1413 1414
	/* Remove the devices that don't need to be closed */
	list_for_each_entry_safe(dev, tmp, head, close_list)
1415
		if (!(dev->flags & IFF_UP))
1416
			list_del_init(&dev->close_list);
1417 1418

	__dev_close_many(head);
L
Linus Torvalds 已提交
1419

1420
	list_for_each_entry_safe(dev, tmp, head, close_list) {
1421
		rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1422
		call_netdevice_notifiers(NETDEV_DOWN, dev);
1423 1424
		if (unlink)
			list_del_init(&dev->close_list);
1425
	}
1426 1427 1428

	return 0;
}
1429
EXPORT_SYMBOL(dev_close_many);
1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441

/**
 *	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)
{
1442 1443
	if (dev->flags & IFF_UP) {
		LIST_HEAD(single);
L
Linus Torvalds 已提交
1444

1445
		list_add(&dev->close_list, &single);
1446
		dev_close_many(&single, true);
1447 1448
		list_del(&single);
	}
1449
	return 0;
L
Linus Torvalds 已提交
1450
}
E
Eric Dumazet 已提交
1451
EXPORT_SYMBOL(dev_close);
L
Linus Torvalds 已提交
1452 1453


1454 1455 1456 1457 1458 1459 1460 1461 1462 1463
/**
 *	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)
{
1464 1465
	struct net_device *lower_dev;
	struct list_head *iter;
1466

M
Michał Mirosław 已提交
1467 1468
	dev->wanted_features &= ~NETIF_F_LRO;
	netdev_update_features(dev);
1469

1470 1471
	if (unlikely(dev->features & NETIF_F_LRO))
		netdev_WARN(dev, "failed to disable LRO!\n");
1472 1473 1474

	netdev_for_each_lower_dev(dev, lower_dev, iter)
		dev_disable_lro(lower_dev);
1475 1476 1477
}
EXPORT_SYMBOL(dev_disable_lro);

1478 1479 1480 1481 1482 1483 1484 1485
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);
}
1486

1487 1488
static int dev_boot_phase = 1;

L
Linus Torvalds 已提交
1489 1490 1491 1492 1493 1494 1495 1496 1497 1498
/**
 *	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
1499
 *	to the new notifier to allow device to have a race free
L
Linus Torvalds 已提交
1500 1501 1502 1503 1504 1505
 *	view of the network device list.
 */

int register_netdevice_notifier(struct notifier_block *nb)
{
	struct net_device *dev;
1506
	struct net_device *last;
1507
	struct net *net;
L
Linus Torvalds 已提交
1508 1509 1510
	int err;

	rtnl_lock();
1511
	err = raw_notifier_chain_register(&netdev_chain, nb);
1512 1513
	if (err)
		goto unlock;
1514 1515 1516 1517
	if (dev_boot_phase)
		goto unlock;
	for_each_net(net) {
		for_each_netdev(net, dev) {
1518
			err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
1519 1520 1521 1522 1523 1524
			err = notifier_to_errno(err);
			if (err)
				goto rollback;

			if (!(dev->flags & IFF_UP))
				continue;
L
Linus Torvalds 已提交
1525

1526
			call_netdevice_notifier(nb, NETDEV_UP, dev);
1527
		}
L
Linus Torvalds 已提交
1528
	}
1529 1530

unlock:
L
Linus Torvalds 已提交
1531 1532
	rtnl_unlock();
	return err;
1533 1534 1535

rollback:
	last = dev;
1536 1537 1538
	for_each_net(net) {
		for_each_netdev(net, dev) {
			if (dev == last)
1539
				goto outroll;
1540

1541
			if (dev->flags & IFF_UP) {
1542 1543 1544
				call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
							dev);
				call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1545
			}
1546
			call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1547 1548
		}
	}
1549

1550
outroll:
1551
	raw_notifier_chain_unregister(&netdev_chain, nb);
1552
	goto unlock;
L
Linus Torvalds 已提交
1553
}
E
Eric Dumazet 已提交
1554
EXPORT_SYMBOL(register_netdevice_notifier);
L
Linus Torvalds 已提交
1555 1556 1557 1558 1559 1560 1561 1562 1563

/**
 *	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.
1564 1565 1566 1567
 *
 * 	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
1568 1569 1570 1571
 */

int unregister_netdevice_notifier(struct notifier_block *nb)
{
1572 1573
	struct net_device *dev;
	struct net *net;
1574 1575 1576
	int err;

	rtnl_lock();
1577
	err = raw_notifier_chain_unregister(&netdev_chain, nb);
1578 1579 1580 1581 1582 1583
	if (err)
		goto unlock;

	for_each_net(net) {
		for_each_netdev(net, dev) {
			if (dev->flags & IFF_UP) {
1584 1585 1586
				call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
							dev);
				call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1587
			}
1588
			call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1589 1590 1591
		}
	}
unlock:
1592 1593
	rtnl_unlock();
	return err;
L
Linus Torvalds 已提交
1594
}
E
Eric Dumazet 已提交
1595
EXPORT_SYMBOL(unregister_netdevice_notifier);
L
Linus Torvalds 已提交
1596

1597 1598 1599 1600 1601 1602 1603 1604 1605 1606
/**
 *	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
1607 1608 1609
static int call_netdevice_notifiers_info(unsigned long val,
					 struct net_device *dev,
					 struct netdev_notifier_info *info)
1610 1611 1612 1613 1614 1615
{
	ASSERT_RTNL();
	netdev_notifier_info_init(info, dev);
	return raw_notifier_call_chain(&netdev_chain, val, info);
}

L
Linus Torvalds 已提交
1616 1617 1618
/**
 *	call_netdevice_notifiers - call all network notifier blocks
 *      @val: value passed unmodified to notifier function
1619
 *      @dev: net_device pointer passed unmodified to notifier function
L
Linus Torvalds 已提交
1620 1621
 *
 *	Call all network notifier blocks.  Parameters and return value
1622
 *	are as for raw_notifier_call_chain().
L
Linus Torvalds 已提交
1623 1624
 */

1625
int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
L
Linus Torvalds 已提交
1626
{
1627 1628 1629
	struct netdev_notifier_info info;

	return call_netdevice_notifiers_info(val, dev, &info);
L
Linus Torvalds 已提交
1630
}
1631
EXPORT_SYMBOL(call_netdevice_notifiers);
L
Linus Torvalds 已提交
1632

1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648
#ifdef CONFIG_NET_CLS_ACT
static struct static_key ingress_needed __read_mostly;

void net_inc_ingress_queue(void)
{
	static_key_slow_inc(&ingress_needed);
}
EXPORT_SYMBOL_GPL(net_inc_ingress_queue);

void net_dec_ingress_queue(void)
{
	static_key_slow_dec(&ingress_needed);
}
EXPORT_SYMBOL_GPL(net_dec_ingress_queue);
#endif

1649
static struct static_key netstamp_needed __read_mostly;
1650
#ifdef HAVE_JUMP_LABEL
1651
/* We are not allowed to call static_key_slow_dec() from irq context
1652
 * If net_disable_timestamp() is called from irq context, defer the
1653
 * static_key_slow_dec() calls.
1654 1655 1656
 */
static atomic_t netstamp_needed_deferred;
#endif
L
Linus Torvalds 已提交
1657 1658 1659

void net_enable_timestamp(void)
{
1660 1661 1662 1663 1664
#ifdef HAVE_JUMP_LABEL
	int deferred = atomic_xchg(&netstamp_needed_deferred, 0);

	if (deferred) {
		while (--deferred)
1665
			static_key_slow_dec(&netstamp_needed);
1666 1667 1668
		return;
	}
#endif
1669
	static_key_slow_inc(&netstamp_needed);
L
Linus Torvalds 已提交
1670
}
E
Eric Dumazet 已提交
1671
EXPORT_SYMBOL(net_enable_timestamp);
L
Linus Torvalds 已提交
1672 1673 1674

void net_disable_timestamp(void)
{
1675 1676 1677 1678 1679 1680
#ifdef HAVE_JUMP_LABEL
	if (in_interrupt()) {
		atomic_inc(&netstamp_needed_deferred);
		return;
	}
#endif
1681
	static_key_slow_dec(&netstamp_needed);
L
Linus Torvalds 已提交
1682
}
E
Eric Dumazet 已提交
1683
EXPORT_SYMBOL(net_disable_timestamp);
L
Linus Torvalds 已提交
1684

E
Eric Dumazet 已提交
1685
static inline void net_timestamp_set(struct sk_buff *skb)
L
Linus Torvalds 已提交
1686
{
1687
	skb->tstamp.tv64 = 0;
1688
	if (static_key_false(&netstamp_needed))
1689
		__net_timestamp(skb);
L
Linus Torvalds 已提交
1690 1691
}

1692
#define net_timestamp_check(COND, SKB)			\
1693
	if (static_key_false(&netstamp_needed)) {		\
1694 1695 1696
		if ((COND) && !(SKB)->tstamp.tv64)	\
			__net_timestamp(SKB);		\
	}						\
E
Eric Dumazet 已提交
1697

1698
bool is_skb_forwardable(struct net_device *dev, struct sk_buff *skb)
1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716
{
	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;
}
1717
EXPORT_SYMBOL_GPL(is_skb_forwardable);
1718

H
Herbert Xu 已提交
1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735
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);
1736
	skb->priority = 0;
H
Herbert Xu 已提交
1737
	skb->protocol = eth_type_trans(skb, dev);
1738
	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
H
Herbert Xu 已提交
1739 1740 1741 1742 1743

	return 0;
}
EXPORT_SYMBOL_GPL(__dev_forward_skb);

1744 1745 1746 1747 1748 1749 1750 1751
/**
 * dev_forward_skb - loopback an skb to another netif
 *
 * @dev: destination network device
 * @skb: buffer to forward
 *
 * return values:
 *	NET_RX_SUCCESS	(no congestion)
1752
 *	NET_RX_DROP     (packet was dropped, but freed)
1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763
 *
 * 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
1764
	return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb);
1765 1766 1767
}
EXPORT_SYMBOL_GPL(dev_forward_skb);

1768 1769 1770 1771
static inline int deliver_skb(struct sk_buff *skb,
			      struct packet_type *pt_prev,
			      struct net_device *orig_dev)
{
1772 1773
	if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
		return -ENOMEM;
1774 1775 1776 1777
	atomic_inc(&skb->users);
	return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
}

1778 1779
static inline void deliver_ptype_list_skb(struct sk_buff *skb,
					  struct packet_type **pt,
1780 1781
					  struct net_device *orig_dev,
					  __be16 type,
1782 1783 1784 1785 1786 1787 1788 1789
					  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)
1790
			deliver_skb(skb, pt_prev, orig_dev);
1791 1792 1793 1794 1795
		pt_prev = ptype;
	}
	*pt = pt_prev;
}

1796 1797
static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
{
1798
	if (!ptype->af_packet_priv || !skb->sk)
1799 1800 1801 1802 1803 1804 1805 1806 1807 1808
		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
1809 1810 1811 1812 1813
/*
 *	Support routine. Sends outgoing frames to any network
 *	taps currently in use.
 */

1814
static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
L
Linus Torvalds 已提交
1815 1816
{
	struct packet_type *ptype;
1817 1818
	struct sk_buff *skb2 = NULL;
	struct packet_type *pt_prev = NULL;
1819
	struct list_head *ptype_list = &ptype_all;
1820

L
Linus Torvalds 已提交
1821
	rcu_read_lock();
1822 1823
again:
	list_for_each_entry_rcu(ptype, ptype_list, list) {
L
Linus Torvalds 已提交
1824 1825 1826
		/* Never send packets back to the socket
		 * they originated from - MvS (miquels@drinkel.ow.org)
		 */
1827 1828
		if (skb_loop_sk(ptype, skb))
			continue;
1829

1830 1831 1832 1833 1834
		if (pt_prev) {
			deliver_skb(skb2, pt_prev, skb->dev);
			pt_prev = ptype;
			continue;
		}
L
Linus Torvalds 已提交
1835

1836 1837 1838 1839
		/* need to clone skb, done only once */
		skb2 = skb_clone(skb, GFP_ATOMIC);
		if (!skb2)
			goto out_unlock;
1840

1841
		net_timestamp_set(skb2);
L
Linus Torvalds 已提交
1842

1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854
		/* 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
1855
		}
1856 1857 1858 1859 1860 1861 1862 1863 1864

		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
1865
	}
1866
out_unlock:
1867 1868
	if (pt_prev)
		pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
L
Linus Torvalds 已提交
1869 1870 1871
	rcu_read_unlock();
}

1872 1873
/**
 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884
 * @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
1885
static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1886 1887 1888 1889 1890 1891
{
	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) {
1892
		pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
1893 1894 1895 1896 1897 1898 1899 1900 1901 1902
		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) {
1903 1904
			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);
1905 1906 1907 1908 1909
			netdev_set_prio_tc_map(dev, i, 0);
		}
	}
}

1910 1911 1912 1913 1914
#ifdef CONFIG_XPS
static DEFINE_MUTEX(xps_map_mutex);
#define xmap_dereference(P)		\
	rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))

1915 1916
static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps,
					int cpu, u16 index)
1917
{
1918 1919
	struct xps_map *map = NULL;
	int pos;
1920

1921 1922
	if (dev_maps)
		map = xmap_dereference(dev_maps->cpu_map[cpu]);
1923

1924 1925
	for (pos = 0; map && pos < map->len; pos++) {
		if (map->queues[pos] == index) {
1926 1927 1928
			if (map->len > 1) {
				map->queues[pos] = map->queues[--map->len];
			} else {
1929
				RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL);
1930 1931 1932
				kfree_rcu(map, rcu);
				map = NULL;
			}
1933
			break;
1934 1935 1936
		}
	}

1937 1938 1939
	return map;
}

1940
static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
1941 1942
{
	struct xps_dev_maps *dev_maps;
1943
	int cpu, i;
1944 1945 1946 1947 1948 1949 1950 1951 1952
	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) {
1953 1954 1955 1956 1957
		for (i = index; i < dev->num_tx_queues; i++) {
			if (!remove_xps_queue(dev_maps, cpu, i))
				break;
		}
		if (i == dev->num_tx_queues)
1958 1959 1960 1961
			active = true;
	}

	if (!active) {
1962 1963 1964 1965
		RCU_INIT_POINTER(dev->xps_maps, NULL);
		kfree_rcu(dev_maps, rcu);
	}

1966 1967 1968 1969
	for (i = index; i < dev->num_tx_queues; i++)
		netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
					     NUMA_NO_NODE);

1970 1971 1972 1973
out_no_maps:
	mutex_unlock(&xps_map_mutex);
}

1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008
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;
}

2009 2010
int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
			u16 index)
2011
{
2012
	struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
2013 2014
	struct xps_map *map, *new_map;
	int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES);
2015 2016
	int cpu, numa_node_id = -2;
	bool active = false;
2017 2018 2019 2020 2021

	mutex_lock(&xps_map_mutex);

	dev_maps = xmap_dereference(dev->xps_maps);

2022 2023 2024 2025 2026 2027 2028
	/* 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);
2029 2030
		if (!new_dev_maps) {
			mutex_unlock(&xps_map_mutex);
2031
			return -ENOMEM;
2032
		}
2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046

		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;

2047
	for_each_possible_cpu(cpu) {
2048 2049 2050 2051 2052 2053 2054 2055 2056 2057
		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;
2058 2059 2060 2061 2062 2063
#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
2064 2065 2066 2067
		} 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);
2068
		}
2069

2070 2071
	}

2072 2073
	rcu_assign_pointer(dev->xps_maps, new_dev_maps);

2074
	/* Cleanup old maps */
2075 2076 2077 2078 2079 2080 2081
	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);
		}
2082

2083
		kfree_rcu(dev_maps, rcu);
2084 2085
	}

2086 2087
	dev_maps = new_dev_maps;
	active = true;
2088

2089 2090
out_no_new_maps:
	/* update Tx queue numa node */
2091 2092 2093 2094
	netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
				     (numa_node_id >= 0) ? numa_node_id :
				     NUMA_NO_NODE);

2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113
	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:
2114 2115 2116 2117
	mutex_unlock(&xps_map_mutex);

	return 0;
error:
2118 2119 2120 2121 2122 2123 2124 2125 2126
	/* 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);
	}

2127 2128 2129 2130 2131 2132 2133 2134
	mutex_unlock(&xps_map_mutex);

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

#endif
2135 2136 2137 2138
/*
 * 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.
 */
2139
int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2140
{
T
Tom Herbert 已提交
2141 2142
	int rc;

2143 2144
	if (txq < 1 || txq > dev->num_tx_queues)
		return -EINVAL;
2145

2146 2147
	if (dev->reg_state == NETREG_REGISTERED ||
	    dev->reg_state == NETREG_UNREGISTERING) {
2148 2149
		ASSERT_RTNL();

T
Tom Herbert 已提交
2150 2151
		rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
						  txq);
T
Tom Herbert 已提交
2152 2153 2154
		if (rc)
			return rc;

2155 2156 2157
		if (dev->num_tc)
			netif_setup_tc(dev, txq);

2158
		if (txq < dev->real_num_tx_queues) {
2159
			qdisc_reset_all_tx_gt(dev, txq);
2160 2161 2162 2163
#ifdef CONFIG_XPS
			netif_reset_xps_queues_gt(dev, txq);
#endif
		}
2164
	}
2165 2166 2167

	dev->real_num_tx_queues = txq;
	return 0;
2168 2169
}
EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2170

2171
#ifdef CONFIG_SYSFS
2172 2173 2174 2175 2176 2177 2178
/**
 *	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
2179 2180
 *	negative error code.  If called before registration, it always
 *	succeeds.
2181 2182 2183 2184 2185
 */
int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
{
	int rc;

T
Tom Herbert 已提交
2186 2187 2188
	if (rxq < 1 || rxq > dev->num_rx_queues)
		return -EINVAL;

2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203
	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

2204 2205
/**
 * netif_get_num_default_rss_queues - default number of RSS queues
2206 2207 2208 2209
 *
 * This routine should set an upper limit on the number of RSS queues
 * used by default by multiqueue devices.
 */
2210
int netif_get_num_default_rss_queues(void)
2211 2212 2213 2214 2215
{
	return min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
}
EXPORT_SYMBOL(netif_get_num_default_rss_queues);

2216
static inline void __netif_reschedule(struct Qdisc *q)
2217
{
2218 2219
	struct softnet_data *sd;
	unsigned long flags;
2220

2221
	local_irq_save(flags);
2222
	sd = this_cpu_ptr(&softnet_data);
2223 2224 2225
	q->next_sched = NULL;
	*sd->output_queue_tailp = q;
	sd->output_queue_tailp = &q->next_sched;
2226 2227 2228 2229 2230 2231 2232 2233
	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);
2234 2235 2236
}
EXPORT_SYMBOL(__netif_schedule);

2237 2238 2239 2240 2241
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)
2242
{
2243 2244 2245
	return (struct dev_kfree_skb_cb *)skb->cb;
}

2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292
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);

2293
void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2294
{
2295
	unsigned long flags;
2296

2297 2298 2299 2300 2301
	if (likely(atomic_read(&skb->users) == 1)) {
		smp_rmb();
		atomic_set(&skb->users, 0);
	} else if (likely(!atomic_dec_and_test(&skb->users))) {
		return;
2302
	}
2303 2304 2305 2306 2307 2308
	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);
2309
}
2310
EXPORT_SYMBOL(__dev_kfree_skb_irq);
2311

2312
void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2313 2314
{
	if (in_irq() || irqs_disabled())
2315
		__dev_kfree_skb_irq(skb, reason);
2316 2317 2318
	else
		dev_kfree_skb(skb);
}
2319
EXPORT_SYMBOL(__dev_kfree_skb_any);
2320 2321


2322 2323 2324 2325 2326 2327
/**
 * netif_device_detach - mark device as removed
 * @dev: network device
 *
 * Mark device as removed from system and therefore no longer available.
 */
2328 2329 2330 2331
void netif_device_detach(struct net_device *dev)
{
	if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
	    netif_running(dev)) {
2332
		netif_tx_stop_all_queues(dev);
2333 2334 2335 2336
	}
}
EXPORT_SYMBOL(netif_device_detach);

2337 2338 2339 2340 2341 2342
/**
 * netif_device_attach - mark device as attached
 * @dev: network device
 *
 * Mark device as attached from system and restart if needed.
 */
2343 2344 2345 2346
void netif_device_attach(struct net_device *dev)
{
	if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
	    netif_running(dev)) {
2347
		netif_tx_wake_all_queues(dev);
2348
		__netdev_watchdog_up(dev);
2349 2350 2351 2352
	}
}
EXPORT_SYMBOL(netif_device_attach);

2353 2354
static void skb_warn_bad_offload(const struct sk_buff *skb)
{
2355
	static const netdev_features_t null_features = 0;
2356 2357 2358
	struct net_device *dev = skb->dev;
	const char *driver = "";

2359 2360 2361
	if (!net_ratelimit())
		return;

2362 2363 2364 2365 2366
	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",
2367 2368
	     driver, dev ? &dev->features : &null_features,
	     skb->sk ? &skb->sk->sk_route_caps : &null_features,
2369 2370 2371 2372
	     skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
	     skb_shinfo(skb)->gso_type, skb->ip_summed);
}

L
Linus Torvalds 已提交
2373 2374 2375 2376
/*
 * Invalidate hardware checksum when packet is to be mangled, and
 * complete checksum manually on outgoing path.
 */
2377
int skb_checksum_help(struct sk_buff *skb)
L
Linus Torvalds 已提交
2378
{
2379
	__wsum csum;
2380
	int ret = 0, offset;
L
Linus Torvalds 已提交
2381

2382
	if (skb->ip_summed == CHECKSUM_COMPLETE)
2383 2384 2385
		goto out_set_summed;

	if (unlikely(skb_shinfo(skb)->gso_size)) {
2386 2387
		skb_warn_bad_offload(skb);
		return -EINVAL;
L
Linus Torvalds 已提交
2388 2389
	}

2390 2391 2392 2393 2394 2395 2396 2397 2398
	/* 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;
	}

2399
	offset = skb_checksum_start_offset(skb);
2400 2401 2402 2403 2404 2405 2406 2407
	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
2408 2409 2410 2411 2412
		ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
		if (ret)
			goto out;
	}

2413
	*(__sum16 *)(skb->data + offset) = csum_fold(csum);
2414
out_set_summed:
L
Linus Torvalds 已提交
2415
	skb->ip_summed = CHECKSUM_NONE;
2416
out:
L
Linus Torvalds 已提交
2417 2418
	return ret;
}
E
Eric Dumazet 已提交
2419
EXPORT_SYMBOL(skb_checksum_help);
L
Linus Torvalds 已提交
2420

2421
__be16 skb_network_protocol(struct sk_buff *skb, int *depth)
2422
{
A
Al Viro 已提交
2423
	__be16 type = skb->protocol;
2424

2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435
	/* 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;
	}

2436
	return __vlan_get_protocol(skb, type, depth);
2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448
}

/**
 *	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;
2449 2450
	int vlan_depth = skb->mac_len;
	__be16 type = skb_network_protocol(skb, &vlan_depth);
2451 2452 2453 2454

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

2455
	__skb_pull(skb, vlan_depth);
2456 2457

	rcu_read_lock();
2458
	list_for_each_entry_rcu(ptype, &offload_base, list) {
2459 2460
		if (ptype->type == type && ptype->callbacks.gso_segment) {
			segs = ptype->callbacks.gso_segment(skb, features);
2461 2462 2463 2464 2465
			break;
		}
	}
	rcu_read_unlock();

2466
	__skb_push(skb, skb->data - skb_mac_header(skb));
2467

2468 2469
	return segs;
}
2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501
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);

2502 2503
		err = skb_cow_head(skb, 0);
		if (err < 0)
2504 2505 2506
			return ERR_PTR(err);
	}

2507
	SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2508 2509
	SKB_GSO_CB(skb)->encap_level = 0;

2510 2511 2512 2513 2514
	skb_reset_mac_header(skb);
	skb_reset_mac_len(skb);

	return skb_mac_gso_segment(skb, features);
}
2515
EXPORT_SYMBOL(__skb_gso_segment);
2516

2517 2518 2519 2520 2521
/* Take action when hardware reception checksum errors are detected. */
#ifdef CONFIG_BUG
void netdev_rx_csum_fault(struct net_device *dev)
{
	if (net_ratelimit()) {
2522
		pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2523 2524 2525 2526 2527 2528
		dump_stack();
	}
}
EXPORT_SYMBOL(netdev_rx_csum_fault);
#endif

L
Linus Torvalds 已提交
2529 2530 2531 2532 2533
/* 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.
 */

2534
static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
L
Linus Torvalds 已提交
2535
{
2536
#ifdef CONFIG_HIGHMEM
L
Linus Torvalds 已提交
2537
	int i;
2538
	if (!(dev->features & NETIF_F_HIGHDMA)) {
2539 2540 2541
		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)))
2542
				return 1;
2543
		}
2544
	}
L
Linus Torvalds 已提交
2545

2546 2547
	if (PCI_DMA_BUS_IS_PHYS) {
		struct device *pdev = dev->dev.parent;
L
Linus Torvalds 已提交
2548

E
Eric Dumazet 已提交
2549 2550
		if (!pdev)
			return 0;
2551
		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2552 2553
			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
			dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2554 2555 2556 2557
			if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
				return 1;
		}
	}
2558
#endif
L
Linus Torvalds 已提交
2559 2560 2561
	return 0;
}

2562 2563 2564
/* 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
2565
#if IS_ENABLED(CONFIG_NET_MPLS_GSO)
2566 2567 2568 2569
static netdev_features_t net_mpls_features(struct sk_buff *skb,
					   netdev_features_t features,
					   __be16 type)
{
2570
	if (eth_p_mpls(type))
2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583
		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

2584
static netdev_features_t harmonize_features(struct sk_buff *skb,
2585
	netdev_features_t features)
2586
{
2587
	int tmp;
2588 2589 2590 2591
	__be16 type;

	type = skb_network_protocol(skb, &tmp);
	features = net_mpls_features(skb, features, type);
2592

2593
	if (skb->ip_summed != CHECKSUM_NONE &&
2594
	    !can_checksum_protocol(features, type)) {
2595
		features &= ~NETIF_F_ALL_CSUM;
2596
	} else if (illegal_highdma(skb->dev, skb)) {
2597 2598 2599 2600 2601 2602
		features &= ~NETIF_F_SG;
	}

	return features;
}

2603 2604 2605 2606 2607 2608 2609 2610
netdev_features_t passthru_features_check(struct sk_buff *skb,
					  struct net_device *dev,
					  netdev_features_t features)
{
	return features;
}
EXPORT_SYMBOL(passthru_features_check);

2611 2612 2613 2614 2615 2616 2617
static netdev_features_t dflt_features_check(const struct sk_buff *skb,
					     struct net_device *dev,
					     netdev_features_t features)
{
	return vlan_features_check(skb, features);
}

2618
netdev_features_t netif_skb_features(struct sk_buff *skb)
2619
{
2620
	struct net_device *dev = skb->dev;
2621 2622
	netdev_features_t features = dev->features;
	u16 gso_segs = skb_shinfo(skb)->gso_segs;
2623

2624
	if (gso_segs > dev->gso_max_segs || gso_segs < dev->gso_min_segs)
2625 2626
		features &= ~NETIF_F_GSO_MASK;

2627 2628 2629 2630 2631 2632 2633
	/* 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;

2634 2635 2636 2637 2638
	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);
2639

2640 2641 2642
	if (dev->netdev_ops->ndo_features_check)
		features &= dev->netdev_ops->ndo_features_check(skb, dev,
								features);
2643 2644
	else
		features &= dflt_features_check(skb, dev, features);
2645

2646
	return harmonize_features(skb, features);
2647
}
2648
EXPORT_SYMBOL(netif_skb_features);
2649

2650
static int xmit_one(struct sk_buff *skb, struct net_device *dev,
2651
		    struct netdev_queue *txq, bool more)
2652
{
2653 2654
	unsigned int len;
	int rc;
2655

2656
	if (!list_empty(&ptype_all) || !list_empty(&dev->ptype_all))
2657
		dev_queue_xmit_nit(skb, dev);
2658

2659 2660
	len = skb->len;
	trace_net_dev_start_xmit(skb, dev);
2661
	rc = netdev_start_xmit(skb, dev, txq, more);
2662
	trace_net_dev_xmit(skb, rc, dev, len);
E
Eric Dumazet 已提交
2663

2664 2665
	return rc;
}
2666

2667 2668
struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev,
				    struct netdev_queue *txq, int *ret)
2669 2670 2671
{
	struct sk_buff *skb = first;
	int rc = NETDEV_TX_OK;
2672

2673 2674
	while (skb) {
		struct sk_buff *next = skb->next;
2675

2676
		skb->next = NULL;
2677
		rc = xmit_one(skb, dev, txq, next != NULL);
2678 2679 2680 2681
		if (unlikely(!dev_xmit_complete(rc))) {
			skb->next = next;
			goto out;
		}
2682

2683 2684 2685 2686
		skb = next;
		if (netif_xmit_stopped(txq) && skb) {
			rc = NETDEV_TX_BUSY;
			break;
2687
		}
2688
	}
2689

2690 2691 2692 2693
out:
	*ret = rc;
	return skb;
}
2694

E
Eric Dumazet 已提交
2695 2696
static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
					  netdev_features_t features)
2697
{
2698
	if (skb_vlan_tag_present(skb) &&
2699 2700
	    !vlan_hw_offload_capable(features, skb->vlan_proto))
		skb = __vlan_hwaccel_push_inside(skb);
2701 2702
	return skb;
}
2703

2704
static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev)
2705 2706
{
	netdev_features_t features;
2707

2708 2709
	if (skb->next)
		return skb;
2710

2711 2712 2713 2714
	features = netif_skb_features(skb);
	skb = validate_xmit_vlan(skb, features);
	if (unlikely(!skb))
		goto out_null;
2715

2716
	if (netif_needs_gso(skb, features)) {
2717 2718 2719
		struct sk_buff *segs;

		segs = skb_gso_segment(skb, features);
2720
		if (IS_ERR(segs)) {
2721
			goto out_kfree_skb;
2722 2723 2724
		} else if (segs) {
			consume_skb(skb);
			skb = segs;
2725
		}
2726 2727 2728 2729
	} else {
		if (skb_needs_linearize(skb, features) &&
		    __skb_linearize(skb))
			goto out_kfree_skb;
2730

2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744
		/* 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;
2745
		}
2746
	}
2747

2748
	return skb;
2749

2750 2751
out_kfree_skb:
	kfree_skb(skb);
2752 2753 2754
out_null:
	return NULL;
}
2755

2756 2757 2758 2759
struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev)
{
	struct sk_buff *next, *head = NULL, *tail;

2760
	for (; skb != NULL; skb = next) {
2761 2762
		next = skb->next;
		skb->next = NULL;
2763 2764 2765 2766

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

2767
		skb = validate_xmit_skb(skb, dev);
2768 2769
		if (!skb)
			continue;
2770

2771 2772 2773 2774 2775 2776 2777 2778
		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;
2779 2780
	}
	return head;
2781 2782
}

2783 2784 2785 2786 2787 2788 2789 2790 2791 2792
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)  {
2793
		unsigned int hdr_len;
2794
		u16 gso_segs = shinfo->gso_segs;
2795

2796 2797 2798 2799
		/* mac layer + network layer */
		hdr_len = skb_transport_header(skb) - skb_mac_header(skb);

		/* + transport layer */
2800 2801 2802 2803
		if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
			hdr_len += tcp_hdrlen(skb);
		else
			hdr_len += sizeof(struct udphdr);
2804 2805 2806 2807 2808 2809

		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;
2810 2811 2812
	}
}

2813 2814 2815 2816 2817
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
2818
	bool contended;
2819 2820
	int rc;

2821
	qdisc_pkt_len_init(skb);
E
Eric Dumazet 已提交
2822
	qdisc_calculate_pkt_len(skb, q);
2823 2824 2825
	/*
	 * Heuristic to force contended enqueues to serialize on a
	 * separate lock before trying to get qdisc main lock.
Y
Ying Xue 已提交
2826 2827
	 * This permits __QDISC___STATE_RUNNING owner to get the lock more
	 * often and dequeue packets faster.
2828
	 */
E
Eric Dumazet 已提交
2829
	contended = qdisc_is_running(q);
2830 2831 2832
	if (unlikely(contended))
		spin_lock(&q->busylock);

2833 2834 2835 2836 2837
	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) &&
2838
		   qdisc_run_begin(q)) {
2839 2840 2841 2842 2843
		/*
		 * 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.
		 */
2844 2845 2846

		qdisc_bstats_update(q, skb);

2847
		if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) {
2848 2849 2850 2851
			if (unlikely(contended)) {
				spin_unlock(&q->busylock);
				contended = false;
			}
2852
			__qdisc_run(q);
2853
		} else
2854
			qdisc_run_end(q);
2855 2856 2857

		rc = NET_XMIT_SUCCESS;
	} else {
E
Eric Dumazet 已提交
2858
		rc = q->enqueue(skb, q) & NET_XMIT_MASK;
2859 2860 2861 2862 2863 2864 2865
		if (qdisc_run_begin(q)) {
			if (unlikely(contended)) {
				spin_unlock(&q->busylock);
				contended = false;
			}
			__qdisc_run(q);
		}
2866 2867
	}
	spin_unlock(root_lock);
2868 2869
	if (unlikely(contended))
		spin_unlock(&q->busylock);
2870 2871 2872
	return rc;
}

2873
#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
2874 2875
static void skb_update_prio(struct sk_buff *skb)
{
I
Igor Maravic 已提交
2876
	struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
2877

2878 2879 2880 2881 2882 2883
	if (!skb->priority && skb->sk && map) {
		unsigned int prioidx = skb->sk->sk_cgrp_prioidx;

		if (prioidx < map->priomap_len)
			skb->priority = map->priomap[prioidx];
	}
2884 2885 2886 2887 2888
}
#else
#define skb_update_prio(skb)
#endif

2889 2890 2891
DEFINE_PER_CPU(int, xmit_recursion);
EXPORT_SYMBOL(xmit_recursion);

2892
#define RECURSION_LIMIT 10
2893

2894 2895 2896 2897
/**
 *	dev_loopback_xmit - loop back @skb
 *	@skb: buffer to transmit
 */
2898
int dev_loopback_xmit(struct sock *sk, struct sk_buff *skb)
2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910
{
	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);

2911
/**
2912
 *	__dev_queue_xmit - transmit a buffer
2913
 *	@skb: buffer to transmit
2914
 *	@accel_priv: private data used for L2 forwarding offload
2915 2916 2917 2918 2919 2920 2921 2922 2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936
 *
 *	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
 */
2937
static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
L
Linus Torvalds 已提交
2938 2939
{
	struct net_device *dev = skb->dev;
2940
	struct netdev_queue *txq;
L
Linus Torvalds 已提交
2941 2942 2943
	struct Qdisc *q;
	int rc = -ENOMEM;

2944 2945
	skb_reset_mac_header(skb);

2946 2947 2948
	if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
		__skb_tstamp_tx(skb, NULL, skb->sk, SCM_TSTAMP_SCHED);

2949 2950
	/* Disable soft irqs for various locks below. Also
	 * stops preemption for RCU.
L
Linus Torvalds 已提交
2951
	 */
2952
	rcu_read_lock_bh();
L
Linus Torvalds 已提交
2953

2954 2955
	skb_update_prio(skb);

2956 2957 2958 2959 2960 2961 2962 2963
	/* 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);

2964
	txq = netdev_pick_tx(dev, skb, accel_priv);
2965
	q = rcu_dereference_bh(txq->qdisc);
2966

L
Linus Torvalds 已提交
2967
#ifdef CONFIG_NET_CLS_ACT
E
Eric Dumazet 已提交
2968
	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
L
Linus Torvalds 已提交
2969
#endif
2970
	trace_net_dev_queue(skb);
L
Linus Torvalds 已提交
2971
	if (q->enqueue) {
2972
		rc = __dev_xmit_skb(skb, q, dev, txq);
2973
		goto out;
L
Linus Torvalds 已提交
2974 2975 2976 2977 2978
	}

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

H
Herbert Xu 已提交
2979 2980
	   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
2981 2982 2983 2984 2985 2986 2987 2988 2989 2990
	   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 */

2991
		if (txq->xmit_lock_owner != cpu) {
L
Linus Torvalds 已提交
2992

2993 2994 2995
			if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
				goto recursion_alert;

2996 2997 2998 2999
			skb = validate_xmit_skb(skb, dev);
			if (!skb)
				goto drop;

3000
			HARD_TX_LOCK(dev, txq, cpu);
L
Linus Torvalds 已提交
3001

3002
			if (!netif_xmit_stopped(txq)) {
3003
				__this_cpu_inc(xmit_recursion);
3004
				skb = dev_hard_start_xmit(skb, dev, txq, &rc);
3005
				__this_cpu_dec(xmit_recursion);
3006
				if (dev_xmit_complete(rc)) {
3007
					HARD_TX_UNLOCK(dev, txq);
L
Linus Torvalds 已提交
3008 3009 3010
					goto out;
				}
			}
3011
			HARD_TX_UNLOCK(dev, txq);
3012 3013
			net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
					     dev->name);
L
Linus Torvalds 已提交
3014 3015
		} else {
			/* Recursion is detected! It is possible,
3016 3017 3018
			 * unfortunately
			 */
recursion_alert:
3019 3020
			net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
					     dev->name);
L
Linus Torvalds 已提交
3021 3022 3023 3024
		}
	}

	rc = -ENETDOWN;
3025
drop:
3026
	rcu_read_unlock_bh();
L
Linus Torvalds 已提交
3027

3028
	atomic_long_inc(&dev->tx_dropped);
3029
	kfree_skb_list(skb);
L
Linus Torvalds 已提交
3030 3031
	return rc;
out:
3032
	rcu_read_unlock_bh();
L
Linus Torvalds 已提交
3033 3034
	return rc;
}
3035

3036
int dev_queue_xmit_sk(struct sock *sk, struct sk_buff *skb)
3037 3038 3039
{
	return __dev_queue_xmit(skb, NULL);
}
3040
EXPORT_SYMBOL(dev_queue_xmit_sk);
L
Linus Torvalds 已提交
3041

3042 3043 3044 3045 3046 3047
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
3048 3049 3050 3051 3052

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

3053
int netdev_max_backlog __read_mostly = 1000;
E
Eric Dumazet 已提交
3054 3055
EXPORT_SYMBOL(netdev_max_backlog);

E
Eric Dumazet 已提交
3056
int netdev_tstamp_prequeue __read_mostly = 1;
3057 3058
int netdev_budget __read_mostly = 300;
int weight_p __read_mostly = 64;            /* old backlog weight */
L
Linus Torvalds 已提交
3059

E
Eric Dumazet 已提交
3060 3061 3062 3063 3064 3065 3066 3067
/* 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);
}

3068 3069 3070
#ifdef CONFIG_RPS

/* One global table that all flow-based protocols share. */
E
Eric Dumazet 已提交
3071
struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
3072
EXPORT_SYMBOL(rps_sock_flow_table);
3073 3074
u32 rps_cpu_mask __read_mostly;
EXPORT_SYMBOL(rps_cpu_mask);
3075

3076
struct static_key rps_needed __read_mostly;
3077

3078 3079 3080 3081
static struct rps_dev_flow *
set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
	    struct rps_dev_flow *rflow, u16 next_cpu)
{
3082
	if (next_cpu != RPS_NO_CPU) {
3083 3084 3085 3086 3087 3088 3089 3090 3091
#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? */
3092 3093
		if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
		    !(dev->features & NETIF_F_NTUPLE))
3094 3095 3096 3097 3098 3099 3100 3101 3102
			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;
3103
		flow_id = skb_get_hash(skb) & flow_table->mask;
3104 3105 3106 3107 3108 3109 3110 3111 3112 3113 3114 3115
		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 =
3116
			per_cpu(softnet_data, next_cpu).input_queue_head;
3117 3118
	}

3119
	rflow->cpu = next_cpu;
3120 3121 3122
	return rflow;
}

3123 3124 3125 3126 3127 3128 3129 3130
/*
 * 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)
{
3131 3132
	const struct rps_sock_flow_table *sock_flow_table;
	struct netdev_rx_queue *rxqueue = dev->_rx;
3133
	struct rps_dev_flow_table *flow_table;
3134
	struct rps_map *map;
3135
	int cpu = -1;
3136
	u32 tcpu;
3137
	u32 hash;
3138 3139 3140

	if (skb_rx_queue_recorded(skb)) {
		u16 index = skb_get_rx_queue(skb);
3141

3142 3143 3144 3145 3146
		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);
3147 3148
			goto done;
		}
3149 3150
		rxqueue += index;
	}
3151

3152 3153 3154
	/* 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
3155
	map = rcu_dereference(rxqueue->rps_map);
3156
	if (!flow_table && !map)
3157 3158
		goto done;

3159
	skb_reset_network_header(skb);
3160 3161
	hash = skb_get_hash(skb);
	if (!hash)
3162 3163
		goto done;

T
Tom Herbert 已提交
3164 3165 3166
	sock_flow_table = rcu_dereference(rps_sock_flow_table);
	if (flow_table && sock_flow_table) {
		struct rps_dev_flow *rflow;
3167 3168 3169 3170 3171 3172 3173
		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
3174

3175 3176 3177 3178 3179
		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
		 */
3180
		rflow = &flow_table->flows[hash & flow_table->mask];
T
Tom Herbert 已提交
3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196
		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 -
3197 3198
		      rflow->last_qtail)) >= 0)) {
			tcpu = next_cpu;
3199
			rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3200
		}
3201

T
Tom Herbert 已提交
3202 3203 3204 3205 3206 3207 3208
		if (tcpu != RPS_NO_CPU && cpu_online(tcpu)) {
			*rflowp = rflow;
			cpu = tcpu;
			goto done;
		}
	}

3209 3210
try_rps:

T
Tom Herbert 已提交
3211
	if (map) {
3212
		tcpu = map->cpus[reciprocal_scale(hash, map->len)];
T
Tom Herbert 已提交
3213 3214 3215 3216 3217 3218 3219 3220 3221 3222
		if (cpu_online(tcpu)) {
			cpu = tcpu;
			goto done;
		}
	}

done:
	return cpu;
}

3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236 3237 3238 3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261 3262
#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
3263
/* Called from hardirq (IPI) context */
E
Eric Dumazet 已提交
3264
static void rps_trigger_softirq(void *data)
T
Tom Herbert 已提交
3265
{
E
Eric Dumazet 已提交
3266 3267
	struct softnet_data *sd = data;

E
Eric Dumazet 已提交
3268
	____napi_schedule(sd, &sd->backlog);
C
Changli Gao 已提交
3269
	sd->received_rps++;
T
Tom Herbert 已提交
3270
}
E
Eric Dumazet 已提交
3271

T
Tom Herbert 已提交
3272
#endif /* CONFIG_RPS */
T
Tom Herbert 已提交
3273

E
Eric Dumazet 已提交
3274 3275 3276 3277 3278 3279 3280 3281
/*
 * 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
3282
	struct softnet_data *mysd = this_cpu_ptr(&softnet_data);
E
Eric Dumazet 已提交
3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294

	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;
}

3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308
#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;

3309
	sd = this_cpu_ptr(&softnet_data);
3310 3311 3312 3313

	rcu_read_lock();
	fl = rcu_dereference(sd->flow_limit);
	if (fl) {
3314
		new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334
		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
3335 3336 3337 3338
/*
 * 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
3339 3340
static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
			      unsigned int *qtail)
T
Tom Herbert 已提交
3341
{
E
Eric Dumazet 已提交
3342
	struct softnet_data *sd;
T
Tom Herbert 已提交
3343
	unsigned long flags;
3344
	unsigned int qlen;
T
Tom Herbert 已提交
3345

E
Eric Dumazet 已提交
3346
	sd = &per_cpu(softnet_data, cpu);
T
Tom Herbert 已提交
3347 3348 3349

	local_irq_save(flags);

E
Eric Dumazet 已提交
3350
	rps_lock(sd);
3351 3352
	qlen = skb_queue_len(&sd->input_pkt_queue);
	if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3353
		if (qlen) {
T
Tom Herbert 已提交
3354
enqueue:
E
Eric Dumazet 已提交
3355
			__skb_queue_tail(&sd->input_pkt_queue, skb);
3356
			input_queue_tail_incr_save(sd, qtail);
E
Eric Dumazet 已提交
3357
			rps_unlock(sd);
3358
			local_irq_restore(flags);
T
Tom Herbert 已提交
3359 3360 3361
			return NET_RX_SUCCESS;
		}

3362 3363 3364 3365
		/* 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
3366
			if (!rps_ipi_queued(sd))
E
Eric Dumazet 已提交
3367
				____napi_schedule(sd, &sd->backlog);
T
Tom Herbert 已提交
3368 3369 3370 3371
		}
		goto enqueue;
	}

C
Changli Gao 已提交
3372
	sd->dropped++;
E
Eric Dumazet 已提交
3373
	rps_unlock(sd);
T
Tom Herbert 已提交
3374 3375 3376

	local_irq_restore(flags);

3377
	atomic_long_inc(&skb->dev->rx_dropped);
T
Tom Herbert 已提交
3378 3379 3380
	kfree_skb(skb);
	return NET_RX_DROP;
}
L
Linus Torvalds 已提交
3381

3382
static int netif_rx_internal(struct sk_buff *skb)
L
Linus Torvalds 已提交
3383
{
3384
	int ret;
L
Linus Torvalds 已提交
3385

3386
	net_timestamp_check(netdev_tstamp_prequeue, skb);
L
Linus Torvalds 已提交
3387

3388
	trace_netif_rx(skb);
E
Eric Dumazet 已提交
3389
#ifdef CONFIG_RPS
3390
	if (static_key_false(&rps_needed)) {
T
Tom Herbert 已提交
3391
		struct rps_dev_flow voidflow, *rflow = &voidflow;
3392 3393
		int cpu;

3394
		preempt_disable();
3395
		rcu_read_lock();
T
Tom Herbert 已提交
3396 3397

		cpu = get_rps_cpu(skb->dev, skb, &rflow);
3398 3399
		if (cpu < 0)
			cpu = smp_processor_id();
T
Tom Herbert 已提交
3400 3401 3402

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

3403
		rcu_read_unlock();
3404
		preempt_enable();
3405 3406
	} else
#endif
T
Tom Herbert 已提交
3407 3408 3409 3410 3411
	{
		unsigned int qtail;
		ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
		put_cpu();
	}
3412
	return ret;
L
Linus Torvalds 已提交
3413
}
3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426 3427 3428 3429 3430 3431 3432 3433 3434 3435

/**
 *	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
3436
EXPORT_SYMBOL(netif_rx);
L
Linus Torvalds 已提交
3437 3438 3439 3440 3441

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

3442 3443
	trace_netif_rx_ni_entry(skb);

L
Linus Torvalds 已提交
3444
	preempt_disable();
3445
	err = netif_rx_internal(skb);
L
Linus Torvalds 已提交
3446 3447 3448 3449 3450 3451 3452 3453 3454 3455
	if (local_softirq_pending())
		do_softirq();
	preempt_enable();

	return err;
}
EXPORT_SYMBOL(netif_rx_ni);

static void net_tx_action(struct softirq_action *h)
{
3456
	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
L
Linus Torvalds 已提交
3457 3458 3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469

	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;

3470
			WARN_ON(atomic_read(&skb->users));
3471 3472 3473 3474
			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
3475 3476 3477 3478 3479
			__kfree_skb(skb);
		}
	}

	if (sd->output_queue) {
3480
		struct Qdisc *head;
L
Linus Torvalds 已提交
3481 3482 3483 3484

		local_irq_disable();
		head = sd->output_queue;
		sd->output_queue = NULL;
3485
		sd->output_queue_tailp = &sd->output_queue;
L
Linus Torvalds 已提交
3486 3487 3488
		local_irq_enable();

		while (head) {
3489 3490 3491
			struct Qdisc *q = head;
			spinlock_t *root_lock;

L
Linus Torvalds 已提交
3492 3493
			head = head->next_sched;

3494
			root_lock = qdisc_lock(q);
3495
			if (spin_trylock(root_lock)) {
3496
				smp_mb__before_atomic();
3497 3498
				clear_bit(__QDISC_STATE_SCHED,
					  &q->state);
3499 3500
				qdisc_run(q);
				spin_unlock(root_lock);
L
Linus Torvalds 已提交
3501
			} else {
3502
				if (!test_bit(__QDISC_STATE_DEACTIVATED,
3503
					      &q->state)) {
3504
					__netif_reschedule(q);
3505
				} else {
3506
					smp_mb__before_atomic();
3507 3508 3509
					clear_bit(__QDISC_STATE_SCHED,
						  &q->state);
				}
L
Linus Torvalds 已提交
3510 3511 3512 3513 3514
			}
		}
	}
}

3515 3516
#if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
    (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
3517 3518 3519
/* This hook is defined here for ATM LANE */
int (*br_fdb_test_addr_hook)(struct net_device *dev,
			     unsigned char *addr) __read_mostly;
3520
EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3521
#endif
L
Linus Torvalds 已提交
3522 3523 3524 3525 3526 3527

#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
3528 3529
 * 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
3530 3531
 *
 */
3532
static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
L
Linus Torvalds 已提交
3533 3534
{
	struct net_device *dev = skb->dev;
3535
	u32 ttl = G_TC_RTTL(skb->tc_verd);
3536 3537
	int result = TC_ACT_OK;
	struct Qdisc *q;
3538

3539
	if (unlikely(MAX_RED_LOOP < ttl++)) {
3540 3541
		net_warn_ratelimited("Redir loop detected Dropping packet (%d->%d)\n",
				     skb->skb_iif, dev->ifindex);
3542 3543
		return TC_ACT_SHOT;
	}
L
Linus Torvalds 已提交
3544

3545 3546
	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
3547

3548
	q = rcu_dereference(rxq->qdisc);
3549
	if (q != &noop_qdisc) {
3550
		spin_lock(qdisc_lock(q));
3551 3552
		if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
			result = qdisc_enqueue_root(skb, q);
3553 3554
		spin_unlock(qdisc_lock(q));
	}
3555 3556 3557

	return result;
}
3558

3559 3560 3561 3562
static inline struct sk_buff *handle_ing(struct sk_buff *skb,
					 struct packet_type **pt_prev,
					 int *ret, struct net_device *orig_dev)
{
3563 3564
	struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);

3565
	if (!rxq || rcu_access_pointer(rxq->qdisc) == &noop_qdisc)
3566
		return skb;
L
Linus Torvalds 已提交
3567

3568 3569 3570
	if (*pt_prev) {
		*ret = deliver_skb(skb, *pt_prev, orig_dev);
		*pt_prev = NULL;
L
Linus Torvalds 已提交
3571 3572
	}

3573
	switch (ing_filter(skb, rxq)) {
3574 3575 3576 3577 3578 3579 3580
	case TC_ACT_SHOT:
	case TC_ACT_STOLEN:
		kfree_skb(skb);
		return NULL;
	}

	return skb;
L
Linus Torvalds 已提交
3581 3582 3583
}
#endif

3584 3585 3586 3587
/**
 *	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
3588
 *	@rx_handler_data: data pointer that is used by rx handler
3589
 *
3590
 *	Register a receive handler for a device. This handler will then be
3591 3592 3593 3594
 *	called from __netif_receive_skb. A negative errno code is returned
 *	on a failure.
 *
 *	The caller must hold the rtnl_mutex.
3595 3596
 *
 *	For a general description of rx_handler, see enum rx_handler_result.
3597 3598
 */
int netdev_rx_handler_register(struct net_device *dev,
J
Jiri Pirko 已提交
3599 3600
			       rx_handler_func_t *rx_handler,
			       void *rx_handler_data)
3601 3602 3603 3604 3605 3606
{
	ASSERT_RTNL();

	if (dev->rx_handler)
		return -EBUSY;

3607
	/* Note: rx_handler_data must be set before rx_handler */
J
Jiri Pirko 已提交
3608
	rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3609 3610 3611 3612 3613 3614 3615 3616 3617 3618
	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
3619
 *	Unregister a receive handler from a device.
3620 3621 3622 3623 3624 3625 3626
 *
 *	The caller must hold the rtnl_mutex.
 */
void netdev_rx_handler_unregister(struct net_device *dev)
{

	ASSERT_RTNL();
3627
	RCU_INIT_POINTER(dev->rx_handler, NULL);
3628 3629 3630 3631 3632
	/* 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();
3633
	RCU_INIT_POINTER(dev->rx_handler_data, NULL);
3634 3635 3636
}
EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);

3637 3638 3639 3640 3641 3642 3643
/*
 * 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) {
3644 3645 3646 3647 3648
	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):
3649 3650 3651 3652 3653 3654
		return true;
	default:
		return false;
	}
}

3655
static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
L
Linus Torvalds 已提交
3656 3657
{
	struct packet_type *ptype, *pt_prev;
3658
	rx_handler_func_t *rx_handler;
D
David S. Miller 已提交
3659
	struct net_device *orig_dev;
3660
	bool deliver_exact = false;
L
Linus Torvalds 已提交
3661
	int ret = NET_RX_DROP;
A
Al Viro 已提交
3662
	__be16 type;
L
Linus Torvalds 已提交
3663

3664
	net_timestamp_check(!netdev_tstamp_prequeue, skb);
3665

3666
	trace_netif_receive_skb(skb);
3667

J
Joe Eykholt 已提交
3668
	orig_dev = skb->dev;
3669

3670
	skb_reset_network_header(skb);
3671 3672
	if (!skb_transport_header_was_set(skb))
		skb_reset_transport_header(skb);
3673
	skb_reset_mac_len(skb);
L
Linus Torvalds 已提交
3674 3675 3676 3677 3678

	pt_prev = NULL;

	rcu_read_lock();

3679
another_round:
3680
	skb->skb_iif = skb->dev->ifindex;
3681 3682 3683

	__this_cpu_inc(softnet_data.processed);

P
Patrick McHardy 已提交
3684 3685
	if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
	    skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
3686
		skb = skb_vlan_untag(skb);
3687
		if (unlikely(!skb))
3688
			goto unlock;
3689 3690
	}

L
Linus Torvalds 已提交
3691 3692 3693 3694 3695 3696 3697
#ifdef CONFIG_NET_CLS_ACT
	if (skb->tc_verd & TC_NCLS) {
		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
		goto ncls;
	}
#endif

3698
	if (pfmemalloc)
3699 3700
		goto skip_taps;

L
Linus Torvalds 已提交
3701
	list_for_each_entry_rcu(ptype, &ptype_all, list) {
3702 3703 3704 3705 3706 3707 3708 3709 3710
		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
3711 3712
	}

3713
skip_taps:
L
Linus Torvalds 已提交
3714
#ifdef CONFIG_NET_CLS_ACT
3715 3716 3717 3718 3719 3720 3721
	if (static_key_false(&ingress_needed)) {
		skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
		if (!skb)
			goto unlock;
	}

	skb->tc_verd = 0;
L
Linus Torvalds 已提交
3722 3723
ncls:
#endif
3724
	if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
3725 3726
		goto drop;

3727
	if (skb_vlan_tag_present(skb)) {
3728 3729 3730 3731
		if (pt_prev) {
			ret = deliver_skb(skb, pt_prev, orig_dev);
			pt_prev = NULL;
		}
3732
		if (vlan_do_receive(&skb))
3733 3734
			goto another_round;
		else if (unlikely(!skb))
3735
			goto unlock;
3736 3737
	}

3738
	rx_handler = rcu_dereference(skb->dev->rx_handler);
3739 3740 3741 3742 3743
	if (rx_handler) {
		if (pt_prev) {
			ret = deliver_skb(skb, pt_prev, orig_dev);
			pt_prev = NULL;
		}
3744 3745
		switch (rx_handler(&skb)) {
		case RX_HANDLER_CONSUMED:
3746
			ret = NET_RX_SUCCESS;
3747
			goto unlock;
3748
		case RX_HANDLER_ANOTHER:
3749
			goto another_round;
3750 3751 3752 3753 3754 3755 3756
		case RX_HANDLER_EXACT:
			deliver_exact = true;
		case RX_HANDLER_PASS:
			break;
		default:
			BUG();
		}
3757
	}
L
Linus Torvalds 已提交
3758

3759 3760
	if (unlikely(skb_vlan_tag_present(skb))) {
		if (skb_vlan_tag_get_id(skb))
E
Eric Dumazet 已提交
3761 3762 3763 3764 3765 3766 3767
			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;
	}
3768

3769 3770
	type = skb->protocol;

3771
	/* deliver only exact match when indicated */
3772 3773 3774 3775 3776
	if (likely(!deliver_exact)) {
		deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
				       &ptype_base[ntohs(type) &
						   PTYPE_HASH_MASK]);
	}
3777

3778 3779 3780 3781 3782 3783
	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
3784 3785 3786
	}

	if (pt_prev) {
3787
		if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
3788
			goto drop;
3789 3790
		else
			ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
L
Linus Torvalds 已提交
3791
	} else {
3792
drop:
3793
		atomic_long_inc(&skb->dev->rx_dropped);
L
Linus Torvalds 已提交
3794 3795 3796 3797 3798 3799 3800
		kfree_skb(skb);
		/* Jamal, now you will not able to escape explaining
		 * me how you were going to use this. :-)
		 */
		ret = NET_RX_DROP;
	}

3801
unlock:
L
Linus Torvalds 已提交
3802
	rcu_read_unlock();
3803 3804 3805 3806 3807 3808 3809 3810 3811 3812 3813 3814 3815 3816 3817 3818 3819 3820 3821 3822 3823 3824 3825 3826 3827
	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
3828 3829
	return ret;
}
T
Tom Herbert 已提交
3830

3831
static int netif_receive_skb_internal(struct sk_buff *skb)
T
Tom Herbert 已提交
3832
{
3833
	net_timestamp_check(netdev_tstamp_prequeue, skb);
E
Eric Dumazet 已提交
3834

3835 3836 3837
	if (skb_defer_rx_timestamp(skb))
		return NET_RX_SUCCESS;

E
Eric Dumazet 已提交
3838
#ifdef CONFIG_RPS
3839
	if (static_key_false(&rps_needed)) {
E
Eric Dumazet 已提交
3840 3841
		struct rps_dev_flow voidflow, *rflow = &voidflow;
		int cpu, ret;
T
Tom Herbert 已提交
3842

E
Eric Dumazet 已提交
3843 3844 3845
		rcu_read_lock();

		cpu = get_rps_cpu(skb->dev, skb, &rflow);
T
Tom Herbert 已提交
3846

E
Eric Dumazet 已提交
3847 3848 3849
		if (cpu >= 0) {
			ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
			rcu_read_unlock();
3850
			return ret;
E
Eric Dumazet 已提交
3851
		}
3852
		rcu_read_unlock();
T
Tom Herbert 已提交
3853
	}
3854
#endif
3855
	return __netif_receive_skb(skb);
T
Tom Herbert 已提交
3856
}
3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 3867 3868 3869 3870 3871 3872

/**
 *	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
 */
3873
int netif_receive_skb_sk(struct sock *sk, struct sk_buff *skb)
3874 3875 3876 3877 3878
{
	trace_netif_receive_skb_entry(skb);

	return netif_receive_skb_internal(skb);
}
3879
EXPORT_SYMBOL(netif_receive_skb_sk);
L
Linus Torvalds 已提交
3880

E
Eric Dumazet 已提交
3881 3882 3883
/* Network device is going away, flush any packets still pending
 * Called with irqs disabled.
 */
3884
static void flush_backlog(void *arg)
3885
{
3886
	struct net_device *dev = arg;
3887
	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
3888 3889
	struct sk_buff *skb, *tmp;

E
Eric Dumazet 已提交
3890
	rps_lock(sd);
3891
	skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3892
		if (skb->dev == dev) {
E
Eric Dumazet 已提交
3893
			__skb_unlink(skb, &sd->input_pkt_queue);
3894
			kfree_skb(skb);
3895
			input_queue_head_incr(sd);
3896
		}
3897
	}
E
Eric Dumazet 已提交
3898
	rps_unlock(sd);
3899 3900 3901 3902 3903

	skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
		if (skb->dev == dev) {
			__skb_unlink(skb, &sd->process_queue);
			kfree_skb(skb);
3904
			input_queue_head_incr(sd);
3905 3906
		}
	}
3907 3908
}

3909 3910
static int napi_gro_complete(struct sk_buff *skb)
{
3911
	struct packet_offload *ptype;
3912
	__be16 type = skb->protocol;
3913
	struct list_head *head = &offload_base;
3914 3915
	int err = -ENOENT;

3916 3917
	BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));

3918 3919
	if (NAPI_GRO_CB(skb)->count == 1) {
		skb_shinfo(skb)->gso_size = 0;
3920
		goto out;
3921
	}
3922 3923 3924

	rcu_read_lock();
	list_for_each_entry_rcu(ptype, head, list) {
3925
		if (ptype->type != type || !ptype->callbacks.gro_complete)
3926 3927
			continue;

3928
		err = ptype->callbacks.gro_complete(skb, 0);
3929 3930 3931 3932 3933 3934 3935 3936 3937 3938 3939
		break;
	}
	rcu_read_unlock();

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

out:
3940
	return netif_receive_skb_internal(skb);
3941 3942
}

3943 3944 3945 3946 3947
/* 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)
3948
{
3949
	struct sk_buff *skb, *prev = NULL;
3950

3951 3952 3953 3954 3955 3956 3957
	/* 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) {
3958
		skb->next = NULL;
3959 3960 3961 3962 3963

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

		prev = skb->prev;
3964
		napi_gro_complete(skb);
3965
		napi->gro_count--;
3966 3967 3968 3969
	}

	napi->gro_list = NULL;
}
E
Eric Dumazet 已提交
3970
EXPORT_SYMBOL(napi_gro_flush);
3971

E
Eric Dumazet 已提交
3972 3973 3974 3975
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;
3976
	u32 hash = skb_get_hash_raw(skb);
E
Eric Dumazet 已提交
3977 3978 3979 3980

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

3981 3982 3983 3984 3985 3986 3987
		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
3988 3989 3990 3991
		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),
3992
						      skb_mac_header(skb));
E
Eric Dumazet 已提交
3993 3994
		else if (!diffs)
			diffs = memcmp(skb_mac_header(p),
3995
				       skb_mac_header(skb),
E
Eric Dumazet 已提交
3996 3997 3998 3999 4000
				       maclen);
		NAPI_GRO_CB(p)->same_flow = !diffs;
	}
}

4001 4002 4003 4004 4005 4006 4007 4008 4009 4010 4011 4012 4013 4014
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
4015 4016 4017
	}
}

4018 4019 4020 4021 4022 4023 4024 4025 4026 4027 4028 4029 4030 4031 4032 4033 4034 4035 4036 4037 4038
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
4039
static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4040 4041
{
	struct sk_buff **pp = NULL;
4042
	struct packet_offload *ptype;
4043
	__be16 type = skb->protocol;
4044
	struct list_head *head = &offload_base;
H
Herbert Xu 已提交
4045
	int same_flow;
4046
	enum gro_result ret;
4047
	int grow;
4048

4049
	if (!(skb->dev->features & NETIF_F_GRO))
4050 4051
		goto normal;

4052
	if (skb_is_gso(skb) || skb_has_frag_list(skb) || skb->csum_bad)
4053 4054
		goto normal;

E
Eric Dumazet 已提交
4055 4056
	gro_list_prepare(napi, skb);

4057 4058
	rcu_read_lock();
	list_for_each_entry_rcu(ptype, head, list) {
4059
		if (ptype->type != type || !ptype->callbacks.gro_receive)
4060 4061
			continue;

4062
		skb_set_network_header(skb, skb_gro_offset(skb));
4063
		skb_reset_mac_len(skb);
4064 4065
		NAPI_GRO_CB(skb)->same_flow = 0;
		NAPI_GRO_CB(skb)->flush = 0;
H
Herbert Xu 已提交
4066
		NAPI_GRO_CB(skb)->free = 0;
4067
		NAPI_GRO_CB(skb)->udp_mark = 0;
4068
		NAPI_GRO_CB(skb)->gro_remcsum_start = 0;
4069

4070 4071 4072 4073 4074 4075 4076 4077 4078 4079 4080 4081 4082 4083 4084
		/* 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;
		}
4085

4086
		pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
4087 4088 4089 4090 4091 4092 4093
		break;
	}
	rcu_read_unlock();

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

H
Herbert Xu 已提交
4094
	same_flow = NAPI_GRO_CB(skb)->same_flow;
4095
	ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
H
Herbert Xu 已提交
4096

4097 4098 4099 4100 4101 4102
	if (pp) {
		struct sk_buff *nskb = *pp;

		*pp = nskb->next;
		nskb->next = NULL;
		napi_gro_complete(nskb);
4103
		napi->gro_count--;
4104 4105
	}

H
Herbert Xu 已提交
4106
	if (same_flow)
4107 4108
		goto ok;

4109
	if (NAPI_GRO_CB(skb)->flush)
4110 4111
		goto normal;

4112 4113 4114 4115 4116 4117 4118 4119 4120 4121 4122 4123 4124 4125
	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++;
	}
4126
	NAPI_GRO_CB(skb)->count = 1;
4127
	NAPI_GRO_CB(skb)->age = jiffies;
4128
	NAPI_GRO_CB(skb)->last = skb;
4129
	skb_shinfo(skb)->gso_size = skb_gro_len(skb);
4130 4131
	skb->next = napi->gro_list;
	napi->gro_list = skb;
4132
	ret = GRO_HELD;
4133

4134
pull:
4135 4136 4137
	grow = skb_gro_offset(skb) - skb_headlen(skb);
	if (grow > 0)
		gro_pull_from_frag0(skb, grow);
4138
ok:
4139
	return ret;
4140 4141

normal:
4142 4143
	ret = GRO_NORMAL;
	goto pull;
H
Herbert Xu 已提交
4144
}
4145

4146 4147 4148 4149 4150 4151 4152 4153 4154 4155 4156 4157
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;
}
4158
EXPORT_SYMBOL(gro_find_receive_by_type);
4159 4160 4161 4162 4163 4164 4165 4166 4167 4168 4169 4170 4171

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;
}
4172
EXPORT_SYMBOL(gro_find_complete_by_type);
H
Herbert Xu 已提交
4173

R
Rami Rosen 已提交
4174
static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
H
Herbert Xu 已提交
4175
{
4176 4177
	switch (ret) {
	case GRO_NORMAL:
4178
		if (netif_receive_skb_internal(skb))
4179 4180
			ret = GRO_DROP;
		break;
H
Herbert Xu 已提交
4181

4182
	case GRO_DROP:
H
Herbert Xu 已提交
4183 4184
		kfree_skb(skb);
		break;
4185

4186
	case GRO_MERGED_FREE:
4187 4188 4189 4190
		if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
			kmem_cache_free(skbuff_head_cache, skb);
		else
			__kfree_skb(skb);
4191 4192
		break;

4193 4194 4195
	case GRO_HELD:
	case GRO_MERGED:
		break;
H
Herbert Xu 已提交
4196 4197
	}

4198
	return ret;
4199 4200
}

4201
gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4202
{
4203
	trace_napi_gro_receive_entry(skb);
4204

4205 4206
	skb_gro_reset_offset(skb);

E
Eric Dumazet 已提交
4207
	return napi_skb_finish(dev_gro_receive(napi, skb), skb);
4208 4209 4210
}
EXPORT_SYMBOL(napi_gro_receive);

S
stephen hemminger 已提交
4211
static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
4212
{
4213 4214 4215 4216
	if (unlikely(skb->pfmemalloc)) {
		consume_skb(skb);
		return;
	}
4217
	__skb_pull(skb, skb_headlen(skb));
4218 4219
	/* restore the reserve we had after netdev_alloc_skb_ip_align() */
	skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
4220
	skb->vlan_tci = 0;
H
Herbert Xu 已提交
4221
	skb->dev = napi->dev;
A
Andy Gospodarek 已提交
4222
	skb->skb_iif = 0;
4223 4224
	skb->encapsulation = 0;
	skb_shinfo(skb)->gso_type = 0;
4225
	skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
4226 4227 4228 4229

	napi->skb = skb;
}

4230
struct sk_buff *napi_get_frags(struct napi_struct *napi)
H
Herbert Xu 已提交
4231 4232 4233 4234
{
	struct sk_buff *skb = napi->skb;

	if (!skb) {
4235
		skb = napi_alloc_skb(napi, GRO_MAX_HEAD);
E
Eric Dumazet 已提交
4236
		napi->skb = skb;
4237
	}
4238 4239
	return skb;
}
4240
EXPORT_SYMBOL(napi_get_frags);
4241

4242 4243 4244
static gro_result_t napi_frags_finish(struct napi_struct *napi,
				      struct sk_buff *skb,
				      gro_result_t ret)
4245
{
4246 4247
	switch (ret) {
	case GRO_NORMAL:
4248 4249 4250 4251
	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))
4252
			ret = GRO_DROP;
4253
		break;
H
Herbert Xu 已提交
4254

4255 4256 4257 4258
	case GRO_DROP:
	case GRO_MERGED_FREE:
		napi_reuse_skb(napi, skb);
		break;
4259 4260 4261

	case GRO_MERGED:
		break;
4262
	}
H
Herbert Xu 已提交
4263

4264
	return ret;
H
Herbert Xu 已提交
4265
}
4266

4267 4268 4269 4270
/* 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
4271
static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4272 4273
{
	struct sk_buff *skb = napi->skb;
4274 4275
	const struct ethhdr *eth;
	unsigned int hlen = sizeof(*eth);
4276 4277 4278

	napi->skb = NULL;

4279 4280 4281 4282 4283 4284 4285 4286 4287 4288 4289 4290 4291 4292
	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;
4293
	}
4294 4295 4296 4297 4298 4299 4300 4301
	__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;
4302 4303 4304 4305

	return skb;
}

4306
gro_result_t napi_gro_frags(struct napi_struct *napi)
4307
{
4308
	struct sk_buff *skb = napi_frags_skb(napi);
4309 4310

	if (!skb)
4311
		return GRO_DROP;
4312

4313 4314
	trace_napi_gro_frags_entry(skb);

E
Eric Dumazet 已提交
4315
	return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4316
}
H
Herbert Xu 已提交
4317 4318
EXPORT_SYMBOL(napi_gro_frags);

T
Tom Herbert 已提交
4319 4320 4321 4322 4323 4324 4325 4326 4327 4328 4329 4330 4331 4332 4333 4334 4335 4336 4337 4338 4339 4340 4341 4342 4343
/* 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);

4344
/*
4345
 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
4346 4347 4348 4349 4350 4351 4352 4353 4354 4355 4356 4357 4358 4359 4360 4361 4362
 * 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))
4363
				smp_call_function_single_async(remsd->cpu,
4364
							   &remsd->csd);
4365 4366 4367 4368 4369 4370 4371
			remsd = next;
		}
	} else
#endif
		local_irq_enable();
}

E
Eric Dumazet 已提交
4372 4373 4374 4375 4376 4377 4378 4379 4380
static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
{
#ifdef CONFIG_RPS
	return sd->rps_ipi_list != NULL;
#else
	return false;
#endif
}

4381
static int process_backlog(struct napi_struct *napi, int quota)
L
Linus Torvalds 已提交
4382 4383
{
	int work = 0;
E
Eric Dumazet 已提交
4384
	struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
L
Linus Torvalds 已提交
4385

4386 4387 4388
	/* Check if we have pending ipi, its better to send them now,
	 * not waiting net_rx_action() end.
	 */
E
Eric Dumazet 已提交
4389
	if (sd_has_rps_ipi_waiting(sd)) {
4390 4391 4392
		local_irq_disable();
		net_rps_action_and_irq_enable(sd);
	}
E
Eric Dumazet 已提交
4393

4394
	napi->weight = weight_p;
4395
	local_irq_disable();
4396
	while (1) {
L
Linus Torvalds 已提交
4397
		struct sk_buff *skb;
4398 4399 4400 4401 4402

		while ((skb = __skb_dequeue(&sd->process_queue))) {
			local_irq_enable();
			__netif_receive_skb(skb);
			local_irq_disable();
4403 4404 4405 4406 4407
			input_queue_head_incr(sd);
			if (++work >= quota) {
				local_irq_enable();
				return work;
			}
4408
		}
L
Linus Torvalds 已提交
4409

E
Eric Dumazet 已提交
4410
		rps_lock(sd);
4411
		if (skb_queue_empty(&sd->input_pkt_queue)) {
E
Eric Dumazet 已提交
4412 4413 4414
			/*
			 * Inline a custom version of __napi_complete().
			 * only current cpu owns and manipulates this napi,
4415 4416 4417
			 * 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
4418 4419 4420
			 * and we dont need an smp_mb() memory barrier.
			 */
			napi->state = 0;
4421
			rps_unlock(sd);
E
Eric Dumazet 已提交
4422

4423
			break;
4424
		}
4425 4426 4427

		skb_queue_splice_tail_init(&sd->input_pkt_queue,
					   &sd->process_queue);
E
Eric Dumazet 已提交
4428
		rps_unlock(sd);
4429 4430
	}
	local_irq_enable();
L
Linus Torvalds 已提交
4431

4432 4433
	return work;
}
L
Linus Torvalds 已提交
4434

4435 4436
/**
 * __napi_schedule - schedule for receive
4437
 * @n: entry to schedule
4438
 *
4439 4440
 * The entry's receive function will be scheduled to run.
 * Consider using __napi_schedule_irqoff() if hard irqs are masked.
4441
 */
H
Harvey Harrison 已提交
4442
void __napi_schedule(struct napi_struct *n)
4443 4444
{
	unsigned long flags;
L
Linus Torvalds 已提交
4445

4446
	local_irq_save(flags);
4447
	____napi_schedule(this_cpu_ptr(&softnet_data), n);
4448
	local_irq_restore(flags);
L
Linus Torvalds 已提交
4449
}
4450 4451
EXPORT_SYMBOL(__napi_schedule);

4452 4453 4454 4455 4456 4457 4458 4459 4460 4461 4462 4463
/**
 * __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);

4464 4465 4466 4467
void __napi_complete(struct napi_struct *n)
{
	BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));

E
Eric Dumazet 已提交
4468
	list_del_init(&n->poll_list);
4469
	smp_mb__before_atomic();
4470 4471 4472 4473
	clear_bit(NAPI_STATE_SCHED, &n->state);
}
EXPORT_SYMBOL(__napi_complete);

4474
void napi_complete_done(struct napi_struct *n, int work_done)
4475 4476 4477 4478 4479 4480 4481 4482 4483 4484
{
	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;

4485 4486
	if (n->gro_list) {
		unsigned long timeout = 0;
E
Eric Dumazet 已提交
4487

4488 4489 4490 4491 4492 4493 4494 4495 4496
		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
4497 4498 4499 4500 4501 4502 4503 4504
	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);
	}
4505
}
4506
EXPORT_SYMBOL(napi_complete_done);
4507

E
Eliezer Tamir 已提交
4508 4509 4510 4511 4512 4513 4514 4515 4516 4517 4518 4519 4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531 4532 4533 4534 4535 4536 4537 4538 4539 4540 4541 4542 4543 4544 4545 4546 4547 4548 4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559
/* 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);

4560 4561 4562 4563 4564 4565 4566 4567 4568 4569 4570
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;
}

4571 4572 4573 4574
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);
4575 4576
	hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED);
	napi->timer.function = napi_watchdog;
4577
	napi->gro_count = 0;
4578
	napi->gro_list = NULL;
H
Herbert Xu 已提交
4579
	napi->skb = NULL;
4580
	napi->poll = poll;
E
Eric Dumazet 已提交
4581 4582 4583
	if (weight > NAPI_POLL_WEIGHT)
		pr_err_once("netif_napi_add() called with weight %d on device %s\n",
			    weight, dev->name);
4584 4585 4586
	napi->weight = weight;
	list_add(&napi->dev_list, &dev->napi_list);
	napi->dev = dev;
H
Herbert Xu 已提交
4587
#ifdef CONFIG_NETPOLL
4588 4589 4590 4591 4592 4593 4594
	spin_lock_init(&napi->poll_lock);
	napi->poll_owner = -1;
#endif
	set_bit(NAPI_STATE_SCHED, &napi->state);
}
EXPORT_SYMBOL(netif_napi_add);

4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607 4608
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);

4609 4610
void netif_napi_del(struct napi_struct *napi)
{
4611
	list_del_init(&napi->dev_list);
4612
	napi_free_frags(napi);
4613

E
Eric Dumazet 已提交
4614
	kfree_skb_list(napi->gro_list);
4615
	napi->gro_list = NULL;
4616
	napi->gro_count = 0;
4617 4618 4619
}
EXPORT_SYMBOL(netif_napi_del);

4620 4621 4622 4623 4624 4625 4626 4627 4628 4629 4630 4631 4632 4633 4634 4635 4636 4637 4638 4639 4640 4641 4642 4643 4644 4645 4646 4647 4648 4649 4650 4651 4652 4653 4654 4655 4656 4657 4658 4659 4660 4661 4662 4663 4664
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);
	}

4665 4666 4667 4668 4669 4670 4671 4672 4673
	/* 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;
	}

4674 4675 4676 4677 4678 4679 4680 4681
	list_add_tail(&n->poll_list, repoll);

out_unlock:
	netpoll_poll_unlock(have);

	return work;
}

L
Linus Torvalds 已提交
4682 4683
static void net_rx_action(struct softirq_action *h)
{
4684
	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
4685
	unsigned long time_limit = jiffies + 2;
4686
	int budget = netdev_budget;
E
Eric Dumazet 已提交
4687 4688
	LIST_HEAD(list);
	LIST_HEAD(repoll);
4689

L
Linus Torvalds 已提交
4690
	local_irq_disable();
E
Eric Dumazet 已提交
4691 4692
	list_splice_init(&sd->poll_list, &list);
	local_irq_enable();
L
Linus Torvalds 已提交
4693

H
Herbert Xu 已提交
4694
	for (;;) {
4695
		struct napi_struct *n;
L
Linus Torvalds 已提交
4696

H
Herbert Xu 已提交
4697 4698 4699 4700 4701 4702
		if (list_empty(&list)) {
			if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll))
				return;
			break;
		}

4703 4704 4705
		n = list_first_entry(&list, struct napi_struct, poll_list);
		budget -= napi_poll(n, &repoll);

E
Eric Dumazet 已提交
4706
		/* If softirq window is exhausted then punt.
4707 4708
		 * Allow this to run for 2 jiffies since which will allow
		 * an average latency of 1.5/HZ.
4709
		 */
H
Herbert Xu 已提交
4710 4711 4712 4713 4714
		if (unlikely(budget <= 0 ||
			     time_after_eq(jiffies, time_limit))) {
			sd->time_squeeze++;
			break;
		}
L
Linus Torvalds 已提交
4715
	}
E
Eric Dumazet 已提交
4716 4717 4718 4719 4720 4721 4722 4723 4724

	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);

4725
	net_rps_action_and_irq_enable(sd);
L
Linus Torvalds 已提交
4726 4727
}

4728
struct netdev_adjacent {
J
Jiri Pirko 已提交
4729
	struct net_device *dev;
4730 4731

	/* upper master flag, there can only be one master device per list */
J
Jiri Pirko 已提交
4732
	bool master;
4733 4734 4735 4736

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

4737 4738 4739
	/* private field for the users */
	void *private;

J
Jiri Pirko 已提交
4740 4741 4742 4743
	struct list_head list;
	struct rcu_head rcu;
};

4744 4745
static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
						 struct net_device *adj_dev,
4746
						 struct list_head *adj_list)
J
Jiri Pirko 已提交
4747
{
4748 4749
	struct netdev_adjacent *adj;

4750
	list_for_each_entry(adj, adj_list, list) {
4751 4752
		if (adj->dev == adj_dev)
			return adj;
J
Jiri Pirko 已提交
4753 4754 4755 4756 4757 4758 4759 4760 4761 4762 4763 4764 4765 4766 4767 4768 4769 4770
	}
	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();

4771
	return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper);
J
Jiri Pirko 已提交
4772 4773 4774 4775 4776 4777 4778 4779 4780 4781
}
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
4782
static bool netdev_has_any_upper_dev(struct net_device *dev)
J
Jiri Pirko 已提交
4783 4784 4785
{
	ASSERT_RTNL();

4786
	return !list_empty(&dev->all_adj_list.upper);
J
Jiri Pirko 已提交
4787 4788 4789 4790 4791 4792 4793 4794 4795 4796 4797
}

/**
 * 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)
{
4798
	struct netdev_adjacent *upper;
J
Jiri Pirko 已提交
4799 4800 4801

	ASSERT_RTNL();

4802
	if (list_empty(&dev->adj_list.upper))
J
Jiri Pirko 已提交
4803 4804
		return NULL;

4805
	upper = list_first_entry(&dev->adj_list.upper,
4806
				 struct netdev_adjacent, list);
J
Jiri Pirko 已提交
4807 4808 4809 4810 4811 4812
	if (likely(upper->master))
		return upper->dev;
	return NULL;
}
EXPORT_SYMBOL(netdev_master_upper_dev_get);

4813 4814 4815 4816 4817 4818 4819 4820 4821 4822
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);

4823 4824 4825 4826 4827 4828 4829 4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840 4841 4842 4843 4844 4845 4846 4847 4848
/**
 * 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);

4849 4850
/**
 * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
4851 4852 4853 4854 4855 4856
 * @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.
 */
4857 4858
struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
						     struct list_head **iter)
4859 4860 4861
{
	struct netdev_adjacent *upper;

4862
	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
4863 4864 4865

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

4866
	if (&upper->list == &dev->all_adj_list.upper)
4867 4868 4869 4870 4871 4872
		return NULL;

	*iter = &upper->list;

	return upper->dev;
}
4873
EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
4874

4875 4876 4877 4878 4879 4880 4881 4882 4883 4884 4885 4886 4887 4888 4889 4890 4891 4892 4893 4894 4895
/**
 * 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;

4896
	*iter = lower->list.next;
4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911 4912 4913 4914 4915 4916 4917 4918 4919 4920 4921 4922 4923

	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;

4924
	*iter = &lower->list;
4925 4926 4927 4928 4929

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

4930 4931 4932 4933 4934 4935 4936 4937 4938 4939 4940 4941 4942 4943 4944 4945 4946 4947 4948 4949 4950 4951 4952 4953 4954 4955
/**
 * 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);

4956 4957 4958 4959 4960 4961 4962 4963 4964 4965 4966 4967 4968 4969 4970 4971 4972 4973 4974 4975 4976
/**
 * 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
4977 4978 4979 4980 4981 4982 4983 4984 4985
/**
 * 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)
{
4986
	struct netdev_adjacent *upper;
J
Jiri Pirko 已提交
4987

4988
	upper = list_first_or_null_rcu(&dev->adj_list.upper,
4989
				       struct netdev_adjacent, list);
J
Jiri Pirko 已提交
4990 4991 4992 4993 4994 4995
	if (upper && likely(upper->master))
		return upper->dev;
	return NULL;
}
EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);

4996
static int netdev_adjacent_sysfs_add(struct net_device *dev,
4997 4998 4999 5000 5001 5002 5003 5004 5005
			      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);
}
5006
static void netdev_adjacent_sysfs_del(struct net_device *dev,
5007 5008 5009 5010 5011 5012 5013 5014 5015
			       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);
}

5016 5017 5018 5019 5020 5021 5022 5023
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));
}
5024

5025 5026
static int __netdev_adjacent_dev_insert(struct net_device *dev,
					struct net_device *adj_dev,
5027
					struct list_head *dev_list,
5028
					void *private, bool master)
5029 5030
{
	struct netdev_adjacent *adj;
5031
	int ret;
5032

5033
	adj = __netdev_find_adj(dev, adj_dev, dev_list);
5034 5035 5036 5037 5038 5039 5040 5041 5042 5043 5044 5045 5046

	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;
5047
	adj->private = private;
5048
	dev_hold(adj_dev);
5049 5050 5051

	pr_debug("dev_hold for %s, because of link added from %s to %s\n",
		 adj_dev->name, dev->name, adj_dev->name);
5052

5053
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
5054
		ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
5055 5056 5057 5058
		if (ret)
			goto free_adj;
	}

5059
	/* Ensure that master link is always the first item in list. */
5060 5061 5062 5063
	if (master) {
		ret = sysfs_create_link(&(dev->dev.kobj),
					&(adj_dev->dev.kobj), "master");
		if (ret)
5064
			goto remove_symlinks;
5065

5066
		list_add_rcu(&adj->list, dev_list);
5067
	} else {
5068
		list_add_tail_rcu(&adj->list, dev_list);
5069
	}
5070 5071

	return 0;
5072

5073
remove_symlinks:
5074
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
5075
		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
5076 5077
free_adj:
	kfree(adj);
5078
	dev_put(adj_dev);
5079 5080

	return ret;
5081 5082
}

S
stephen hemminger 已提交
5083 5084 5085
static void __netdev_adjacent_dev_remove(struct net_device *dev,
					 struct net_device *adj_dev,
					 struct list_head *dev_list)
5086 5087 5088
{
	struct netdev_adjacent *adj;

5089
	adj = __netdev_find_adj(dev, adj_dev, dev_list);
5090

5091 5092 5093
	if (!adj) {
		pr_err("tried to remove device %s from %s\n",
		       dev->name, adj_dev->name);
5094
		BUG();
5095
	}
5096 5097

	if (adj->ref_nr > 1) {
5098 5099
		pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name,
			 adj->ref_nr-1);
5100 5101 5102 5103
		adj->ref_nr--;
		return;
	}

5104 5105 5106
	if (adj->master)
		sysfs_remove_link(&(dev->dev.kobj), "master");

5107
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
5108
		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
5109

5110
	list_del_rcu(&adj->list);
5111 5112
	pr_debug("dev_put for %s, because link removed from %s to %s\n",
		 adj_dev->name, dev->name, adj_dev->name);
5113 5114 5115 5116
	dev_put(adj_dev);
	kfree_rcu(adj, rcu);
}

S
stephen hemminger 已提交
5117 5118 5119 5120 5121
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)
5122 5123 5124
{
	int ret;

5125 5126
	ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, private,
					   master);
5127 5128 5129
	if (ret)
		return ret;

5130 5131
	ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, private,
					   false);
5132
	if (ret) {
5133
		__netdev_adjacent_dev_remove(dev, upper_dev, up_list);
5134 5135 5136 5137 5138 5139
		return ret;
	}

	return 0;
}

S
stephen hemminger 已提交
5140 5141
static int __netdev_adjacent_dev_link(struct net_device *dev,
				      struct net_device *upper_dev)
5142
{
5143 5144 5145
	return __netdev_adjacent_dev_link_lists(dev, upper_dev,
						&dev->all_adj_list.upper,
						&upper_dev->all_adj_list.lower,
5146
						NULL, false);
5147 5148
}

S
stephen hemminger 已提交
5149 5150 5151 5152
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)
5153
{
5154 5155
	__netdev_adjacent_dev_remove(dev, upper_dev, up_list);
	__netdev_adjacent_dev_remove(upper_dev, dev, down_list);
5156 5157
}

S
stephen hemminger 已提交
5158 5159
static void __netdev_adjacent_dev_unlink(struct net_device *dev,
					 struct net_device *upper_dev)
5160
{
5161 5162 5163 5164 5165
	__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
5166 5167 5168
static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
						struct net_device *upper_dev,
						void *private, bool master)
5169 5170 5171 5172 5173 5174 5175 5176 5177
{
	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,
5178
					       private, master);
5179 5180 5181 5182 5183 5184
	if (ret) {
		__netdev_adjacent_dev_unlink(dev, upper_dev);
		return ret;
	}

	return 0;
5185 5186
}

S
stephen hemminger 已提交
5187 5188
static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
						   struct net_device *upper_dev)
5189 5190 5191 5192 5193 5194
{
	__netdev_adjacent_dev_unlink(dev, upper_dev);
	__netdev_adjacent_dev_unlink_lists(dev, upper_dev,
					   &dev->adj_list.upper,
					   &upper_dev->adj_list.lower);
}
5195

J
Jiri Pirko 已提交
5196
static int __netdev_upper_dev_link(struct net_device *dev,
5197 5198
				   struct net_device *upper_dev, bool master,
				   void *private)
J
Jiri Pirko 已提交
5199
{
5200 5201
	struct netdev_adjacent *i, *j, *to_i, *to_j;
	int ret = 0;
J
Jiri Pirko 已提交
5202 5203 5204 5205 5206 5207 5208

	ASSERT_RTNL();

	if (dev == upper_dev)
		return -EBUSY;

	/* To prevent loops, check if dev is not upper device to upper_dev. */
5209
	if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper))
J
Jiri Pirko 已提交
5210 5211
		return -EBUSY;

5212
	if (__netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper))
J
Jiri Pirko 已提交
5213 5214 5215 5216 5217
		return -EEXIST;

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

5218 5219
	ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private,
						   master);
5220 5221
	if (ret)
		return ret;
J
Jiri Pirko 已提交
5222

5223
	/* Now that we linked these devs, make all the upper_dev's
5224
	 * all_adj_list.upper visible to every dev's all_adj_list.lower an
5225 5226 5227
	 * versa, and don't forget the devices itself. All of these
	 * links are non-neighbours.
	 */
5228 5229 5230 5231
	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);
5232 5233 5234 5235 5236 5237 5238
			ret = __netdev_adjacent_dev_link(i->dev, j->dev);
			if (ret)
				goto rollback_mesh;
		}
	}

	/* add dev to every upper_dev's upper device */
5239 5240 5241
	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);
5242 5243 5244 5245 5246 5247
		ret = __netdev_adjacent_dev_link(dev, i->dev);
		if (ret)
			goto rollback_upper_mesh;
	}

	/* add upper_dev to every dev's lower device */
5248 5249 5250
	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);
5251 5252 5253 5254
		ret = __netdev_adjacent_dev_link(i->dev, upper_dev);
		if (ret)
			goto rollback_lower_mesh;
	}
J
Jiri Pirko 已提交
5255

5256
	call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
J
Jiri Pirko 已提交
5257
	return 0;
5258 5259 5260

rollback_lower_mesh:
	to_i = i;
5261
	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5262 5263 5264 5265 5266 5267 5268 5269 5270
		if (i == to_i)
			break;
		__netdev_adjacent_dev_unlink(i->dev, upper_dev);
	}

	i = NULL;

rollback_upper_mesh:
	to_i = i;
5271
	list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
5272 5273 5274 5275 5276 5277 5278 5279 5280 5281
		if (i == to_i)
			break;
		__netdev_adjacent_dev_unlink(dev, i->dev);
	}

	i = j = NULL;

rollback_mesh:
	to_i = i;
	to_j = j;
5282 5283
	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
		list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
5284 5285 5286 5287 5288 5289 5290 5291
			if (i == to_i && j == to_j)
				break;
			__netdev_adjacent_dev_unlink(i->dev, j->dev);
		}
		if (i == to_i)
			break;
	}

5292
	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5293 5294

	return ret;
J
Jiri Pirko 已提交
5295 5296 5297 5298 5299 5300 5301 5302 5303 5304 5305 5306 5307 5308 5309
}

/**
 * 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)
{
5310
	return __netdev_upper_dev_link(dev, upper_dev, false, NULL);
J
Jiri Pirko 已提交
5311 5312 5313 5314 5315 5316 5317 5318 5319 5320 5321 5322 5323 5324 5325 5326 5327
}
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)
{
5328
	return __netdev_upper_dev_link(dev, upper_dev, true, NULL);
J
Jiri Pirko 已提交
5329 5330 5331
}
EXPORT_SYMBOL(netdev_master_upper_dev_link);

5332 5333 5334 5335 5336 5337 5338 5339
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
5340 5341 5342 5343 5344 5345 5346 5347 5348 5349 5350
/**
 * 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)
{
5351
	struct netdev_adjacent *i, *j;
J
Jiri Pirko 已提交
5352 5353
	ASSERT_RTNL();

5354
	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5355 5356 5357 5358 5359

	/* 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.
	 */
5360 5361
	list_for_each_entry(i, &dev->all_adj_list.lower, list)
		list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
5362 5363 5364 5365 5366
			__netdev_adjacent_dev_unlink(i->dev, j->dev);

	/* remove also the devices itself from lower/upper device
	 * list
	 */
5367
	list_for_each_entry(i, &dev->all_adj_list.lower, list)
5368 5369
		__netdev_adjacent_dev_unlink(i->dev, upper_dev);

5370
	list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
5371 5372
		__netdev_adjacent_dev_unlink(dev, i->dev);

5373
	call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
J
Jiri Pirko 已提交
5374 5375 5376
}
EXPORT_SYMBOL(netdev_upper_dev_unlink);

5377 5378 5379
/**
 * netdev_bonding_info_change - Dispatch event about slave change
 * @dev: device
5380
 * @bonding_info: info to dispatch
5381 5382 5383 5384 5385 5386 5387 5388 5389 5390 5391 5392 5393 5394 5395 5396
 *
 * 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
5397
static void netdev_adjacent_add_links(struct net_device *dev)
5398 5399 5400 5401 5402 5403 5404 5405 5406 5407 5408 5409 5410 5411 5412 5413 5414 5415 5416 5417 5418 5419 5420 5421
{
	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
5422
static void netdev_adjacent_del_links(struct net_device *dev)
5423 5424 5425 5426 5427 5428 5429 5430 5431 5432 5433 5434 5435 5436 5437 5438 5439 5440 5441 5442 5443 5444 5445 5446
{
	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);
	}
}

5447
void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
5448
{
5449
	struct netdev_adjacent *iter;
5450

5451 5452
	struct net *net = dev_net(dev);

5453
	list_for_each_entry(iter, &dev->adj_list.upper, list) {
5454 5455
		if (!net_eq(net,dev_net(iter->dev)))
			continue;
5456 5457 5458 5459 5460
		netdev_adjacent_sysfs_del(iter->dev, oldname,
					  &iter->dev->adj_list.lower);
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.lower);
	}
5461

5462
	list_for_each_entry(iter, &dev->adj_list.lower, list) {
5463 5464
		if (!net_eq(net,dev_net(iter->dev)))
			continue;
5465 5466 5467 5468 5469
		netdev_adjacent_sysfs_del(iter->dev, oldname,
					  &iter->dev->adj_list.upper);
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.upper);
	}
5470 5471 5472 5473 5474 5475 5476 5477 5478 5479 5480 5481 5482 5483 5484 5485 5486
}

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);

5487 5488 5489 5490 5491 5492 5493 5494 5495 5496 5497 5498 5499 5500 5501 5502 5503 5504 5505 5506 5507 5508 5509 5510

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);

5511 5512
static void dev_change_rx_flags(struct net_device *dev, int flags)
{
5513 5514
	const struct net_device_ops *ops = dev->netdev_ops;

5515
	if (ops->ndo_change_rx_flags)
5516
		ops->ndo_change_rx_flags(dev, flags);
5517 5518
}

5519
static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
L
Linus Torvalds 已提交
5520
{
5521
	unsigned int old_flags = dev->flags;
5522 5523
	kuid_t uid;
	kgid_t gid;
L
Linus Torvalds 已提交
5524

5525 5526
	ASSERT_RTNL();

5527 5528 5529 5530 5531 5532 5533 5534 5535 5536 5537
	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;
5538 5539
			pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
				dev->name);
5540 5541 5542
			return -EOVERFLOW;
		}
	}
5543
	if (dev->flags != old_flags) {
5544 5545 5546
		pr_info("device %s %s promiscuous mode\n",
			dev->name,
			dev->flags & IFF_PROMISC ? "entered" : "left");
5547 5548
		if (audit_enabled) {
			current_uid_gid(&uid, &gid);
5549 5550 5551 5552 5553
			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),
5554
				from_kuid(&init_user_ns, audit_get_loginuid(current)),
5555 5556
				from_kuid(&init_user_ns, uid),
				from_kgid(&init_user_ns, gid),
5557
				audit_get_sessionid(current));
5558
		}
5559

5560
		dev_change_rx_flags(dev, IFF_PROMISC);
L
Linus Torvalds 已提交
5561
	}
5562 5563
	if (notify)
		__dev_notify_flags(dev, old_flags, IFF_PROMISC);
5564
	return 0;
L
Linus Torvalds 已提交
5565 5566
}

5567 5568 5569 5570 5571 5572 5573 5574 5575
/**
 *	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.
5576
 *	Return 0 if successful or a negative errno code on error.
5577
 */
5578
int dev_set_promiscuity(struct net_device *dev, int inc)
5579
{
5580
	unsigned int old_flags = dev->flags;
5581
	int err;
5582

5583
	err = __dev_set_promiscuity(dev, inc, true);
5584
	if (err < 0)
5585
		return err;
5586 5587
	if (dev->flags != old_flags)
		dev_set_rx_mode(dev);
5588
	return err;
5589
}
E
Eric Dumazet 已提交
5590
EXPORT_SYMBOL(dev_set_promiscuity);
5591

5592
static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
L
Linus Torvalds 已提交
5593
{
5594
	unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
L
Linus Torvalds 已提交
5595

5596 5597
	ASSERT_RTNL();

L
Linus Torvalds 已提交
5598
	dev->flags |= IFF_ALLMULTI;
5599 5600 5601 5602 5603 5604 5605 5606 5607 5608
	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;
5609 5610
			pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
				dev->name);
5611 5612 5613
			return -EOVERFLOW;
		}
	}
5614
	if (dev->flags ^ old_flags) {
5615
		dev_change_rx_flags(dev, IFF_ALLMULTI);
5616
		dev_set_rx_mode(dev);
5617 5618 5619
		if (notify)
			__dev_notify_flags(dev, old_flags,
					   dev->gflags ^ old_gflags);
5620
	}
5621
	return 0;
5622
}
5623 5624 5625 5626 5627 5628 5629 5630 5631 5632 5633 5634 5635 5636 5637 5638 5639 5640

/**
 *	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
5641
EXPORT_SYMBOL(dev_set_allmulti);
5642 5643 5644 5645

/*
 *	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
5646
 *	filtering it is put in promiscuous mode while unicast addresses
5647 5648 5649 5650
 *	are present.
 */
void __dev_set_rx_mode(struct net_device *dev)
{
5651 5652
	const struct net_device_ops *ops = dev->netdev_ops;

5653 5654 5655 5656 5657
	/* dev_open will call this function so the list will stay sane. */
	if (!(dev->flags&IFF_UP))
		return;

	if (!netif_device_present(dev))
5658
		return;
5659

5660
	if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
5661 5662 5663
		/* Unicast addresses changes may only happen under the rtnl,
		 * therefore calling __dev_set_promiscuity here is safe.
		 */
5664
		if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
5665
			__dev_set_promiscuity(dev, 1, false);
5666
			dev->uc_promisc = true;
5667
		} else if (netdev_uc_empty(dev) && dev->uc_promisc) {
5668
			__dev_set_promiscuity(dev, -1, false);
5669
			dev->uc_promisc = false;
5670 5671
		}
	}
5672 5673 5674

	if (ops->ndo_set_rx_mode)
		ops->ndo_set_rx_mode(dev);
5675 5676 5677 5678
}

void dev_set_rx_mode(struct net_device *dev)
{
5679
	netif_addr_lock_bh(dev);
5680
	__dev_set_rx_mode(dev);
5681
	netif_addr_unlock_bh(dev);
L
Linus Torvalds 已提交
5682 5683
}

5684 5685 5686 5687 5688 5689
/**
 *	dev_get_flags - get flags reported to userspace
 *	@dev: device
 *
 *	Get the combination of flag bits exported through APIs to userspace.
 */
5690
unsigned int dev_get_flags(const struct net_device *dev)
L
Linus Torvalds 已提交
5691
{
5692
	unsigned int flags;
L
Linus Torvalds 已提交
5693 5694 5695

	flags = (dev->flags & ~(IFF_PROMISC |
				IFF_ALLMULTI |
S
Stefan Rompf 已提交
5696 5697 5698
				IFF_RUNNING |
				IFF_LOWER_UP |
				IFF_DORMANT)) |
L
Linus Torvalds 已提交
5699 5700 5701
		(dev->gflags & (IFF_PROMISC |
				IFF_ALLMULTI));

S
Stefan Rompf 已提交
5702 5703 5704 5705 5706 5707 5708 5709
	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
5710 5711 5712

	return flags;
}
E
Eric Dumazet 已提交
5713
EXPORT_SYMBOL(dev_get_flags);
L
Linus Torvalds 已提交
5714

5715
int __dev_change_flags(struct net_device *dev, unsigned int flags)
L
Linus Torvalds 已提交
5716
{
5717
	unsigned int old_flags = dev->flags;
5718
	int ret;
L
Linus Torvalds 已提交
5719

5720 5721
	ASSERT_RTNL();

L
Linus Torvalds 已提交
5722 5723 5724 5725 5726 5727 5728 5729 5730 5731 5732 5733 5734 5735
	/*
	 *	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.
	 */

5736 5737
	if ((old_flags ^ flags) & IFF_MULTICAST)
		dev_change_rx_flags(dev, IFF_MULTICAST);
5738

5739
	dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
5740 5741 5742 5743 5744 5745 5746 5747

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

	ret = 0;
5748
	if ((old_flags ^ flags) & IFF_UP)
5749
		ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
L
Linus Torvalds 已提交
5750 5751

	if ((flags ^ dev->gflags) & IFF_PROMISC) {
E
Eric Dumazet 已提交
5752
		int inc = (flags & IFF_PROMISC) ? 1 : -1;
5753
		unsigned int old_flags = dev->flags;
E
Eric Dumazet 已提交
5754

L
Linus Torvalds 已提交
5755
		dev->gflags ^= IFF_PROMISC;
5756 5757 5758 5759

		if (__dev_set_promiscuity(dev, inc, false) >= 0)
			if (dev->flags != old_flags)
				dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
5760 5761 5762 5763 5764 5765 5766
	}

	/* 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
5767 5768
		int inc = (flags & IFF_ALLMULTI) ? 1 : -1;

L
Linus Torvalds 已提交
5769
		dev->gflags ^= IFF_ALLMULTI;
5770
		__dev_set_allmulti(dev, inc, false);
L
Linus Torvalds 已提交
5771 5772
	}

5773 5774 5775
	return ret;
}

5776 5777
void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
			unsigned int gchanges)
5778 5779 5780
{
	unsigned int changes = dev->flags ^ old_flags;

5781
	if (gchanges)
5782
		rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
5783

5784 5785 5786 5787 5788 5789 5790 5791
	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 &&
5792 5793 5794 5795 5796 5797 5798
	    (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);
	}
5799 5800 5801 5802 5803 5804 5805 5806 5807 5808
}

/**
 *	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.
 */
5809
int dev_change_flags(struct net_device *dev, unsigned int flags)
5810
{
5811
	int ret;
5812
	unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
5813 5814 5815 5816 5817

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

5818
	changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
5819
	__dev_notify_flags(dev, old_flags, changes);
L
Linus Torvalds 已提交
5820 5821
	return ret;
}
E
Eric Dumazet 已提交
5822
EXPORT_SYMBOL(dev_change_flags);
L
Linus Torvalds 已提交
5823

5824 5825 5826 5827 5828 5829 5830 5831 5832 5833 5834
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;
}

5835 5836 5837 5838 5839 5840 5841
/**
 *	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
5842 5843
int dev_set_mtu(struct net_device *dev, int new_mtu)
{
5844
	int err, orig_mtu;
L
Linus Torvalds 已提交
5845 5846 5847 5848 5849 5850 5851 5852 5853 5854 5855

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

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

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

5856 5857 5858 5859
	err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
	err = notifier_to_errno(err);
	if (err)
		return err;
5860

5861 5862
	orig_mtu = dev->mtu;
	err = __dev_set_mtu(dev, new_mtu);
5863

5864 5865 5866 5867 5868 5869 5870 5871 5872 5873 5874
	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
5875 5876
	return err;
}
E
Eric Dumazet 已提交
5877
EXPORT_SYMBOL(dev_set_mtu);
L
Linus Torvalds 已提交
5878

5879 5880 5881 5882 5883 5884 5885 5886 5887 5888 5889
/**
 *	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);

5890 5891 5892 5893 5894 5895 5896
/**
 *	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
5897 5898
int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
{
5899
	const struct net_device_ops *ops = dev->netdev_ops;
L
Linus Torvalds 已提交
5900 5901
	int err;

5902
	if (!ops->ndo_set_mac_address)
L
Linus Torvalds 已提交
5903 5904 5905 5906 5907
		return -EOPNOTSUPP;
	if (sa->sa_family != dev->type)
		return -EINVAL;
	if (!netif_device_present(dev))
		return -ENODEV;
5908
	err = ops->ndo_set_mac_address(dev, sa);
5909 5910
	if (err)
		return err;
J
Jiri Pirko 已提交
5911
	dev->addr_assign_type = NET_ADDR_SET;
5912
	call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
5913
	add_device_randomness(dev->dev_addr, dev->addr_len);
5914
	return 0;
L
Linus Torvalds 已提交
5915
}
E
Eric Dumazet 已提交
5916
EXPORT_SYMBOL(dev_set_mac_address);
L
Linus Torvalds 已提交
5917

J
Jiri Pirko 已提交
5918 5919 5920
/**
 *	dev_change_carrier - Change device carrier
 *	@dev: device
5921
 *	@new_carrier: new value
J
Jiri Pirko 已提交
5922 5923 5924 5925 5926 5927 5928 5929 5930 5931 5932 5933 5934 5935 5936
 *
 *	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);

5937 5938 5939 5940 5941 5942 5943 5944
/**
 *	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,
5945
			 struct netdev_phys_item_id *ppid)
5946 5947 5948 5949 5950 5951 5952 5953 5954
{
	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);

5955 5956 5957 5958 5959 5960 5961 5962 5963 5964 5965 5966 5967 5968 5969 5970 5971 5972
/**
 *	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
5973 5974
/**
 *	dev_new_index	-	allocate an ifindex
5975
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
5976 5977 5978 5979 5980
 *
 *	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.
 */
5981
static int dev_new_index(struct net *net)
L
Linus Torvalds 已提交
5982
{
5983
	int ifindex = net->ifindex;
L
Linus Torvalds 已提交
5984 5985 5986
	for (;;) {
		if (++ifindex <= 0)
			ifindex = 1;
5987
		if (!__dev_get_by_index(net, ifindex))
5988
			return net->ifindex = ifindex;
L
Linus Torvalds 已提交
5989 5990 5991 5992
	}
}

/* Delayed registration/unregisteration */
5993
static LIST_HEAD(net_todo_list);
5994
DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
L
Linus Torvalds 已提交
5995

5996
static void net_set_todo(struct net_device *dev)
L
Linus Torvalds 已提交
5997 5998
{
	list_add_tail(&dev->todo_list, &net_todo_list);
5999
	dev_net(dev)->dev_unreg_count++;
L
Linus Torvalds 已提交
6000 6001
}

6002
static void rollback_registered_many(struct list_head *head)
6003
{
6004
	struct net_device *dev, *tmp;
6005
	LIST_HEAD(close_head);
6006

6007 6008 6009
	BUG_ON(dev_boot_phase);
	ASSERT_RTNL();

6010
	list_for_each_entry_safe(dev, tmp, head, unreg_list) {
6011
		/* Some devices call without registering
6012 6013
		 * for initialization unwind. Remove those
		 * devices and proceed with the remaining.
6014 6015
		 */
		if (dev->reg_state == NETREG_UNINITIALIZED) {
6016 6017
			pr_debug("unregister_netdevice: device %s/%p never was registered\n",
				 dev->name, dev);
6018

6019
			WARN_ON(1);
6020 6021
			list_del(&dev->unreg_list);
			continue;
6022
		}
6023
		dev->dismantle = true;
6024
		BUG_ON(dev->reg_state != NETREG_REGISTERED);
6025
	}
6026

6027
	/* If device is running, close it first. */
6028 6029
	list_for_each_entry(dev, head, unreg_list)
		list_add_tail(&dev->close_list, &close_head);
6030
	dev_close_many(&close_head, true);
6031

6032
	list_for_each_entry(dev, head, unreg_list) {
6033 6034
		/* And unlink it from device chain. */
		unlist_netdevice(dev);
6035

6036 6037
		dev->reg_state = NETREG_UNREGISTERING;
	}
6038 6039 6040

	synchronize_net();

6041
	list_for_each_entry(dev, head, unreg_list) {
6042 6043
		struct sk_buff *skb = NULL;

6044 6045
		/* Shutdown queueing discipline. */
		dev_shutdown(dev);
6046 6047


6048 6049 6050 6051
		/* Notify protocols, that we are about to destroy
		   this device. They should clean all the things.
		*/
		call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6052

6053 6054 6055 6056 6057
		if (!dev->rtnl_link_ops ||
		    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
			skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U,
						     GFP_KERNEL);

6058 6059 6060
		/*
		 *	Flush the unicast and multicast chains
		 */
6061
		dev_uc_flush(dev);
6062
		dev_mc_flush(dev);
6063

6064 6065
		if (dev->netdev_ops->ndo_uninit)
			dev->netdev_ops->ndo_uninit(dev);
6066

6067 6068
		if (skb)
			rtmsg_ifinfo_send(skb, dev, GFP_KERNEL);
6069

J
Jiri Pirko 已提交
6070 6071
		/* Notifier chain MUST detach us all upper devices. */
		WARN_ON(netdev_has_any_upper_dev(dev));
6072

6073 6074
		/* Remove entries from kobject tree */
		netdev_unregister_kobject(dev);
6075 6076 6077 6078
#ifdef CONFIG_XPS
		/* Remove XPS queueing entries */
		netif_reset_xps_queues_gt(dev, 0);
#endif
6079
	}
6080

6081
	synchronize_net();
6082

6083
	list_for_each_entry(dev, head, unreg_list)
6084 6085 6086 6087 6088 6089 6090 6091 6092
		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
6093
	list_del(&single);
6094 6095
}

6096 6097
static netdev_features_t netdev_fix_features(struct net_device *dev,
	netdev_features_t features)
6098
{
6099 6100 6101
	/* Fix illegal checksum combinations */
	if ((features & NETIF_F_HW_CSUM) &&
	    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
6102
		netdev_warn(dev, "mixed HW and IP checksum settings.\n");
6103 6104 6105
		features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
	}

6106
	/* TSO requires that SG is present as well. */
6107
	if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
6108
		netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
6109
		features &= ~NETIF_F_ALL_TSO;
6110 6111
	}

6112 6113 6114 6115 6116 6117 6118 6119 6120 6121 6122 6123 6124
	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;
	}

6125 6126 6127 6128
	/* TSO ECN requires that TSO is present as well. */
	if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
		features &= ~NETIF_F_TSO_ECN;

6129 6130
	/* Software GSO depends on SG. */
	if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
6131
		netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
6132 6133 6134
		features &= ~NETIF_F_GSO;
	}

6135
	/* UFO needs SG and checksumming */
6136
	if (features & NETIF_F_UFO) {
6137 6138 6139 6140
		/* 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))) {
6141
			netdev_dbg(dev,
6142
				"Dropping NETIF_F_UFO since no checksum offload features.\n");
6143 6144 6145 6146
			features &= ~NETIF_F_UFO;
		}

		if (!(features & NETIF_F_SG)) {
6147
			netdev_dbg(dev,
6148
				"Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
6149 6150 6151 6152
			features &= ~NETIF_F_UFO;
		}
	}

J
Jiri Pirko 已提交
6153 6154 6155 6156 6157 6158 6159
#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;

6160 6161 6162
	return features;
}

6163
int __netdev_update_features(struct net_device *dev)
6164
{
6165
	netdev_features_t features;
6166 6167
	int err = 0;

6168 6169
	ASSERT_RTNL();

6170 6171 6172 6173 6174 6175 6176 6177 6178
	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)
6179
		return 0;
6180

6181 6182
	netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
		&dev->features, &features);
6183 6184 6185 6186

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

6187
	if (unlikely(err < 0)) {
6188
		netdev_err(dev,
6189 6190
			"set_features() failed (%d); wanted %pNF, left %pNF\n",
			err, &features, &dev->features);
6191 6192 6193 6194 6195 6196 6197 6198 6199
		return -1;
	}

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

	return 1;
}

6200 6201 6202 6203 6204 6205 6206 6207
/**
 *	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.
 */
6208 6209 6210 6211
void netdev_update_features(struct net_device *dev)
{
	if (__netdev_update_features(dev))
		netdev_features_change(dev);
6212 6213 6214
}
EXPORT_SYMBOL(netdev_update_features);

6215 6216 6217 6218 6219 6220 6221 6222 6223 6224 6225 6226 6227 6228 6229 6230 6231
/**
 *	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);

6232 6233 6234 6235 6236 6237 6238 6239 6240 6241 6242 6243 6244 6245 6246 6247 6248 6249 6250 6251 6252 6253 6254 6255 6256 6257 6258
/**
 *	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);

6259
#ifdef CONFIG_SYSFS
6260 6261 6262
static int netif_alloc_rx_queues(struct net_device *dev)
{
	unsigned int i, count = dev->num_rx_queues;
T
Tom Herbert 已提交
6263
	struct netdev_rx_queue *rx;
6264
	size_t sz = count * sizeof(*rx);
6265

T
Tom Herbert 已提交
6266
	BUG_ON(count < 1);
6267

6268 6269 6270 6271 6272 6273
	rx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!rx) {
		rx = vzalloc(sz);
		if (!rx)
			return -ENOMEM;
	}
T
Tom Herbert 已提交
6274 6275 6276
	dev->_rx = rx;

	for (i = 0; i < count; i++)
T
Tom Herbert 已提交
6277
		rx[i].dev = dev;
6278 6279
	return 0;
}
T
Tom Herbert 已提交
6280
#endif
6281

C
Changli Gao 已提交
6282 6283 6284 6285 6286 6287 6288
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;
6289
	netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
C
Changli Gao 已提交
6290
	queue->dev = dev;
T
Tom Herbert 已提交
6291 6292 6293
#ifdef CONFIG_BQL
	dql_init(&queue->dql, HZ);
#endif
C
Changli Gao 已提交
6294 6295
}

6296 6297
static void netif_free_tx_queues(struct net_device *dev)
{
W
WANG Cong 已提交
6298
	kvfree(dev->_tx);
6299 6300
}

6301 6302 6303 6304
static int netif_alloc_netdev_queues(struct net_device *dev)
{
	unsigned int count = dev->num_tx_queues;
	struct netdev_queue *tx;
6305
	size_t sz = count * sizeof(*tx);
6306

6307
	BUG_ON(count < 1 || count > 0xffff);
6308

6309 6310 6311 6312 6313 6314
	tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!tx) {
		tx = vzalloc(sz);
		if (!tx)
			return -ENOMEM;
	}
6315
	dev->_tx = tx;
T
Tom Herbert 已提交
6316

6317 6318
	netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
	spin_lock_init(&dev->tx_global_lock);
C
Changli Gao 已提交
6319 6320

	return 0;
6321 6322
}

L
Linus Torvalds 已提交
6323 6324 6325 6326 6327 6328 6329 6330 6331 6332 6333 6334 6335 6336 6337 6338 6339 6340 6341 6342
/**
 *	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;
6343
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
6344 6345 6346 6347

	BUG_ON(dev_boot_phase);
	ASSERT_RTNL();

6348 6349
	might_sleep();

L
Linus Torvalds 已提交
6350 6351
	/* When net_device's are persistent, this will be fatal. */
	BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
6352
	BUG_ON(!net);
L
Linus Torvalds 已提交
6353

6354
	spin_lock_init(&dev->addr_list_lock);
6355
	netdev_set_addr_lockdep_class(dev);
L
Linus Torvalds 已提交
6356

6357
	ret = dev_get_valid_name(net, dev, dev->name);
6358 6359 6360
	if (ret < 0)
		goto out;

L
Linus Torvalds 已提交
6361
	/* Init, if this function is available */
6362 6363
	if (dev->netdev_ops->ndo_init) {
		ret = dev->netdev_ops->ndo_init(dev);
L
Linus Torvalds 已提交
6364 6365 6366
		if (ret) {
			if (ret > 0)
				ret = -EIO;
6367
			goto out;
L
Linus Torvalds 已提交
6368 6369
		}
	}
6370

6371 6372
	if (((dev->hw_features | dev->features) &
	     NETIF_F_HW_VLAN_CTAG_FILTER) &&
6373 6374 6375 6376 6377 6378 6379
	    (!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;
	}

6380 6381 6382 6383 6384 6385
	ret = -EBUSY;
	if (!dev->ifindex)
		dev->ifindex = dev_new_index(net);
	else if (__dev_get_by_index(net, dev->ifindex))
		goto err_uninit;

6386 6387 6388 6389
	/* Transfer changeable features to wanted_features and enable
	 * software offloads (GSO and GRO).
	 */
	dev->hw_features |= NETIF_F_SOFT_FEATURES;
6390 6391
	dev->features |= NETIF_F_SOFT_FEATURES;
	dev->wanted_features = dev->features & dev->hw_features;
L
Linus Torvalds 已提交
6392

6393 6394
	if (!(dev->flags & IFF_LOOPBACK)) {
		dev->hw_features |= NETIF_F_NOCACHE_COPY;
6395 6396
	}

6397
	/* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
6398
	 */
6399
	dev->vlan_features |= NETIF_F_HIGHDMA;
6400

6401 6402 6403 6404
	/* Make NETIF_F_SG inheritable to tunnel devices.
	 */
	dev->hw_enc_features |= NETIF_F_SG;

S
Simon Horman 已提交
6405 6406 6407 6408
	/* Make NETIF_F_SG inheritable to MPLS.
	 */
	dev->mpls_features |= NETIF_F_SG;

6409 6410 6411 6412 6413
	ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
	ret = notifier_to_errno(ret);
	if (ret)
		goto err_uninit;

6414
	ret = netdev_register_kobject(dev);
6415
	if (ret)
6416
		goto err_uninit;
6417 6418
	dev->reg_state = NETREG_REGISTERED;

6419
	__netdev_update_features(dev);
6420

L
Linus Torvalds 已提交
6421 6422 6423 6424 6425 6426 6427
	/*
	 *	Default initial state at registry is that the
	 *	device is present.
	 */

	set_bit(__LINK_STATE_PRESENT, &dev->state);

6428 6429
	linkwatch_init_dev(dev);

L
Linus Torvalds 已提交
6430 6431
	dev_init_scheduler(dev);
	dev_hold(dev);
6432
	list_netdevice(dev);
6433
	add_device_randomness(dev->dev_addr, dev->addr_len);
L
Linus Torvalds 已提交
6434

6435 6436 6437 6438 6439 6440 6441
	/* 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
6442
	/* Notify protocols, that a new device appeared. */
6443
	ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
6444
	ret = notifier_to_errno(ret);
6445 6446 6447 6448
	if (ret) {
		rollback_registered(dev);
		dev->reg_state = NETREG_UNREGISTERED;
	}
6449 6450 6451 6452
	/*
	 *	Prevent userspace races by waiting until the network
	 *	device is fully setup before sending notifications.
	 */
6453 6454
	if (!dev->rtnl_link_ops ||
	    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
6455
		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
L
Linus Torvalds 已提交
6456 6457 6458

out:
	return ret;
6459 6460

err_uninit:
6461 6462
	if (dev->netdev_ops->ndo_uninit)
		dev->netdev_ops->ndo_uninit(dev);
6463
	goto out;
L
Linus Torvalds 已提交
6464
}
E
Eric Dumazet 已提交
6465
EXPORT_SYMBOL(register_netdevice);
L
Linus Torvalds 已提交
6466

6467 6468 6469 6470 6471 6472 6473 6474 6475 6476 6477 6478 6479 6480 6481 6482 6483 6484 6485 6486 6487 6488 6489 6490 6491 6492 6493 6494 6495 6496 6497
/**
 *	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
6498 6499 6500 6501 6502
	/* Note : We dont allocate pcpu_refcnt for dummy devices,
	 * because users of this 'device' dont need to change
	 * its refcount.
	 */

6503 6504 6505 6506 6507
	return 0;
}
EXPORT_SYMBOL_GPL(init_dummy_netdev);


L
Linus Torvalds 已提交
6508 6509 6510 6511 6512 6513 6514 6515 6516
/**
 *	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.
 *
6517
 *	This is a wrapper around register_netdevice that takes the rtnl semaphore
L
Linus Torvalds 已提交
6518 6519 6520 6521 6522 6523 6524 6525 6526 6527 6528 6529 6530 6531
 *	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
6532 6533 6534 6535 6536 6537 6538 6539 6540 6541
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);

6542
/**
L
Linus Torvalds 已提交
6543
 * netdev_wait_allrefs - wait until all references are gone.
6544
 * @dev: target net_device
L
Linus Torvalds 已提交
6545 6546 6547 6548 6549 6550 6551
 *
 * 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
6552
 * call dev_put.
L
Linus Torvalds 已提交
6553 6554 6555 6556
 */
static void netdev_wait_allrefs(struct net_device *dev)
{
	unsigned long rebroadcast_time, warning_time;
E
Eric Dumazet 已提交
6557
	int refcnt;
L
Linus Torvalds 已提交
6558

6559 6560
	linkwatch_forget_dev(dev);

L
Linus Torvalds 已提交
6561
	rebroadcast_time = warning_time = jiffies;
E
Eric Dumazet 已提交
6562 6563 6564
	refcnt = netdev_refcnt_read(dev);

	while (refcnt != 0) {
L
Linus Torvalds 已提交
6565
		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
6566
			rtnl_lock();
L
Linus Torvalds 已提交
6567 6568

			/* Rebroadcast unregister notification */
6569
			call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
L
Linus Torvalds 已提交
6570

6571
			__rtnl_unlock();
6572
			rcu_barrier();
6573 6574
			rtnl_lock();

6575
			call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
L
Linus Torvalds 已提交
6576 6577 6578 6579 6580 6581 6582 6583 6584 6585 6586
			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();
			}

6587
			__rtnl_unlock();
L
Linus Torvalds 已提交
6588 6589 6590 6591 6592 6593

			rebroadcast_time = jiffies;
		}

		msleep(250);

E
Eric Dumazet 已提交
6594 6595
		refcnt = netdev_refcnt_read(dev);

L
Linus Torvalds 已提交
6596
		if (time_after(jiffies, warning_time + 10 * HZ)) {
6597 6598
			pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
				 dev->name, refcnt);
L
Linus Torvalds 已提交
6599 6600 6601 6602 6603 6604 6605 6606 6607 6608 6609 6610 6611 6612 6613 6614 6615 6616 6617
			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
6618
 * We are invoked by rtnl_unlock().
L
Linus Torvalds 已提交
6619
 * This allows us to deal with problems:
6620
 * 1) We can delete sysfs objects which invoke hotplug
L
Linus Torvalds 已提交
6621 6622 6623
 *    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
6624 6625 6626
 *
 * 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
6627 6628 6629
 */
void netdev_run_todo(void)
{
6630
	struct list_head list;
L
Linus Torvalds 已提交
6631 6632

	/* Snapshot list, allow later requests */
6633
	list_replace_init(&net_todo_list, &list);
H
Herbert Xu 已提交
6634 6635

	__rtnl_unlock();
6636

6637 6638

	/* Wait for rcu callbacks to finish before next phase */
6639 6640 6641
	if (!list_empty(&list))
		rcu_barrier();

L
Linus Torvalds 已提交
6642 6643
	while (!list_empty(&list)) {
		struct net_device *dev
6644
			= list_first_entry(&list, struct net_device, todo_list);
L
Linus Torvalds 已提交
6645 6646
		list_del(&dev->todo_list);

6647
		rtnl_lock();
6648
		call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6649
		__rtnl_unlock();
6650

6651
		if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
6652
			pr_err("network todo '%s' but state %d\n",
6653 6654 6655 6656
			       dev->name, dev->reg_state);
			dump_stack();
			continue;
		}
L
Linus Torvalds 已提交
6657

6658
		dev->reg_state = NETREG_UNREGISTERED;
L
Linus Torvalds 已提交
6659

6660
		on_each_cpu(flush_backlog, dev, 1);
6661

6662
		netdev_wait_allrefs(dev);
L
Linus Torvalds 已提交
6663

6664
		/* paranoia */
E
Eric Dumazet 已提交
6665
		BUG_ON(netdev_refcnt_read(dev));
6666 6667
		BUG_ON(!list_empty(&dev->ptype_all));
		BUG_ON(!list_empty(&dev->ptype_specific));
6668 6669
		WARN_ON(rcu_access_pointer(dev->ip_ptr));
		WARN_ON(rcu_access_pointer(dev->ip6_ptr));
6670
		WARN_ON(dev->dn_ptr);
L
Linus Torvalds 已提交
6671

6672 6673
		if (dev->destructor)
			dev->destructor(dev);
6674

6675 6676 6677 6678 6679 6680
		/* Report a network device has been unregistered */
		rtnl_lock();
		dev_net(dev)->dev_unreg_count--;
		__rtnl_unlock();
		wake_up(&netdev_unregistering_wq);

6681 6682
		/* Free network device */
		kobject_put(&dev->dev.kobj);
L
Linus Torvalds 已提交
6683 6684 6685
	}
}

6686 6687 6688
/* Convert net_device_stats to rtnl_link_stats64.  They have the same
 * fields in the same order, with only the type differing.
 */
6689 6690
void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
			     const struct net_device_stats *netdev_stats)
6691 6692
{
#if BITS_PER_LONG == 64
6693 6694
	BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
	memcpy(stats64, netdev_stats, sizeof(*stats64));
6695 6696 6697 6698 6699 6700 6701 6702 6703 6704 6705
#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
}
6706
EXPORT_SYMBOL(netdev_stats_to_stats64);
6707

6708 6709 6710
/**
 *	dev_get_stats	- get network device statistics
 *	@dev: device to get statistics from
6711
 *	@storage: place to store stats
6712
 *
6713 6714 6715 6716
 *	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.
6717
 */
6718 6719
struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
					struct rtnl_link_stats64 *storage)
6720
{
6721 6722
	const struct net_device_ops *ops = dev->netdev_ops;

6723 6724
	if (ops->ndo_get_stats64) {
		memset(storage, 0, sizeof(*storage));
6725 6726
		ops->ndo_get_stats64(dev, storage);
	} else if (ops->ndo_get_stats) {
6727
		netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
6728 6729
	} else {
		netdev_stats_to_stats64(storage, &dev->stats);
6730
	}
6731
	storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
6732
	storage->tx_dropped += atomic_long_read(&dev->tx_dropped);
6733
	return storage;
R
Rusty Russell 已提交
6734
}
6735
EXPORT_SYMBOL(dev_get_stats);
R
Rusty Russell 已提交
6736

6737
struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
6738
{
6739
	struct netdev_queue *queue = dev_ingress_queue(dev);
6740

6741 6742 6743 6744 6745 6746 6747
#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
6748
	RCU_INIT_POINTER(queue->qdisc, &noop_qdisc);
6749 6750 6751 6752
	queue->qdisc_sleeping = &noop_qdisc;
	rcu_assign_pointer(dev->ingress_queue, queue);
#endif
	return queue;
6753 6754
}

6755 6756
static const struct ethtool_ops default_ethtool_ops;

6757 6758 6759 6760 6761 6762 6763 6764
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);

6765 6766 6767 6768
void netdev_freemem(struct net_device *dev)
{
	char *addr = (char *)dev - dev->padded;

W
WANG Cong 已提交
6769
	kvfree(addr);
6770 6771
}

L
Linus Torvalds 已提交
6772
/**
T
Tom Herbert 已提交
6773
 *	alloc_netdev_mqs - allocate network device
6774 6775 6776 6777 6778 6779
 *	@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
6780 6781
 *
 *	Allocates a struct net_device with private data area for driver use
L
Li Zhong 已提交
6782
 *	and performs basic initialization.  Also allocates subqueue structs
T
Tom Herbert 已提交
6783
 *	for each queue on the device.
L
Linus Torvalds 已提交
6784
 */
T
Tom Herbert 已提交
6785
struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
6786
		unsigned char name_assign_type,
T
Tom Herbert 已提交
6787 6788
		void (*setup)(struct net_device *),
		unsigned int txqs, unsigned int rxqs)
L
Linus Torvalds 已提交
6789 6790
{
	struct net_device *dev;
6791
	size_t alloc_size;
6792
	struct net_device *p;
L
Linus Torvalds 已提交
6793

6794 6795
	BUG_ON(strlen(name) >= sizeof(dev->name));

T
Tom Herbert 已提交
6796
	if (txqs < 1) {
6797
		pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
6798 6799 6800
		return NULL;
	}

6801
#ifdef CONFIG_SYSFS
T
Tom Herbert 已提交
6802
	if (rxqs < 1) {
6803
		pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
T
Tom Herbert 已提交
6804 6805 6806 6807
		return NULL;
	}
#endif

6808
	alloc_size = sizeof(struct net_device);
6809 6810
	if (sizeof_priv) {
		/* ensure 32-byte alignment of private area */
6811
		alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
6812 6813 6814
		alloc_size += sizeof_priv;
	}
	/* ensure 32-byte alignment of whole construct */
6815
	alloc_size += NETDEV_ALIGN - 1;
L
Linus Torvalds 已提交
6816

6817 6818 6819
	p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!p)
		p = vzalloc(alloc_size);
6820
	if (!p)
L
Linus Torvalds 已提交
6821 6822
		return NULL;

6823
	dev = PTR_ALIGN(p, NETDEV_ALIGN);
L
Linus Torvalds 已提交
6824
	dev->padded = (char *)dev - (char *)p;
6825

E
Eric Dumazet 已提交
6826 6827
	dev->pcpu_refcnt = alloc_percpu(int);
	if (!dev->pcpu_refcnt)
6828
		goto free_dev;
6829 6830

	if (dev_addr_init(dev))
E
Eric Dumazet 已提交
6831
		goto free_pcpu;
6832

6833
	dev_mc_init(dev);
6834
	dev_uc_init(dev);
J
Jiri Pirko 已提交
6835

6836
	dev_net_set(dev, &init_net);
L
Linus Torvalds 已提交
6837

6838
	dev->gso_max_size = GSO_MAX_SIZE;
6839
	dev->gso_max_segs = GSO_MAX_SEGS;
6840
	dev->gso_min_segs = 0;
6841 6842 6843

	INIT_LIST_HEAD(&dev->napi_list);
	INIT_LIST_HEAD(&dev->unreg_list);
6844
	INIT_LIST_HEAD(&dev->close_list);
6845
	INIT_LIST_HEAD(&dev->link_watch_list);
6846 6847 6848 6849
	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);
6850 6851
	INIT_LIST_HEAD(&dev->ptype_all);
	INIT_LIST_HEAD(&dev->ptype_specific);
6852
	dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM;
6853 6854
	setup(dev);

T
Tom Herbert 已提交
6855 6856
	dev->num_tx_queues = txqs;
	dev->real_num_tx_queues = txqs;
6857
	if (netif_alloc_netdev_queues(dev))
6858
		goto free_all;
6859

6860
#ifdef CONFIG_SYSFS
T
Tom Herbert 已提交
6861 6862
	dev->num_rx_queues = rxqs;
	dev->real_num_rx_queues = rxqs;
T
Tom Herbert 已提交
6863
	if (netif_alloc_rx_queues(dev))
6864
		goto free_all;
E
Eric Dumazet 已提交
6865
#endif
T
Tom Herbert 已提交
6866

L
Linus Torvalds 已提交
6867
	strcpy(dev->name, name);
6868
	dev->name_assign_type = name_assign_type;
6869
	dev->group = INIT_NETDEV_GROUP;
6870 6871
	if (!dev->ethtool_ops)
		dev->ethtool_ops = &default_ethtool_ops;
L
Linus Torvalds 已提交
6872
	return dev;
6873

6874 6875 6876 6877
free_all:
	free_netdev(dev);
	return NULL;

E
Eric Dumazet 已提交
6878 6879
free_pcpu:
	free_percpu(dev->pcpu_refcnt);
6880 6881
free_dev:
	netdev_freemem(dev);
6882
	return NULL;
L
Linus Torvalds 已提交
6883
}
T
Tom Herbert 已提交
6884
EXPORT_SYMBOL(alloc_netdev_mqs);
L
Linus Torvalds 已提交
6885 6886 6887 6888 6889

/**
 *	free_netdev - free network device
 *	@dev: device
 *
6890 6891
 *	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
6892 6893 6894 6895
 *	If this is the last reference then it will be freed.
 */
void free_netdev(struct net_device *dev)
{
6896 6897
	struct napi_struct *p, *n;

6898
	netif_free_tx_queues(dev);
6899
#ifdef CONFIG_SYSFS
6900
	kvfree(dev->_rx);
T
Tom Herbert 已提交
6901
#endif
6902

6903
	kfree(rcu_dereference_protected(dev->ingress_queue, 1));
6904

6905 6906 6907
	/* Flush device addresses */
	dev_addr_flush(dev);

6908 6909 6910
	list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
		netif_napi_del(p);

E
Eric Dumazet 已提交
6911 6912 6913
	free_percpu(dev->pcpu_refcnt);
	dev->pcpu_refcnt = NULL;

S
Stephen Hemminger 已提交
6914
	/*  Compatibility with error handling in drivers */
L
Linus Torvalds 已提交
6915
	if (dev->reg_state == NETREG_UNINITIALIZED) {
6916
		netdev_freemem(dev);
L
Linus Torvalds 已提交
6917 6918 6919 6920 6921 6922
		return;
	}

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

6923 6924
	/* will free via device release */
	put_device(&dev->dev);
L
Linus Torvalds 已提交
6925
}
E
Eric Dumazet 已提交
6926
EXPORT_SYMBOL(free_netdev);
6927

6928 6929 6930 6931 6932 6933
/**
 *	synchronize_net -  Synchronize with packet receive processing
 *
 *	Wait for packets currently being received to be done.
 *	Does not block later packets from starting.
 */
6934
void synchronize_net(void)
L
Linus Torvalds 已提交
6935 6936
{
	might_sleep();
6937 6938 6939 6940
	if (rtnl_is_locked())
		synchronize_rcu_expedited();
	else
		synchronize_rcu();
L
Linus Torvalds 已提交
6941
}
E
Eric Dumazet 已提交
6942
EXPORT_SYMBOL(synchronize_net);
L
Linus Torvalds 已提交
6943 6944

/**
6945
 *	unregister_netdevice_queue - remove device from the kernel
L
Linus Torvalds 已提交
6946
 *	@dev: device
6947
 *	@head: list
6948
 *
L
Linus Torvalds 已提交
6949
 *	This function shuts down a device interface and removes it
6950
 *	from the kernel tables.
6951
 *	If head not NULL, device is queued to be unregistered later.
L
Linus Torvalds 已提交
6952 6953 6954 6955 6956
 *
 *	Callers must hold the rtnl semaphore.  You may want
 *	unregister_netdev() instead of this.
 */

6957
void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
L
Linus Torvalds 已提交
6958
{
6959 6960
	ASSERT_RTNL();

6961
	if (head) {
6962
		list_move_tail(&dev->unreg_list, head);
6963 6964 6965 6966 6967
	} else {
		rollback_registered(dev);
		/* Finish processing unregister after unlock */
		net_set_todo(dev);
	}
L
Linus Torvalds 已提交
6968
}
6969
EXPORT_SYMBOL(unregister_netdevice_queue);
L
Linus Torvalds 已提交
6970

6971 6972 6973
/**
 *	unregister_netdevice_many - unregister many devices
 *	@head: list of devices
6974 6975 6976
 *
 *  Note: As most callers use a stack allocated list_head,
 *  we force a list_del() to make sure stack wont be corrupted later.
6977 6978 6979 6980 6981 6982 6983 6984 6985
 */
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);
6986
		list_del(head);
6987 6988
	}
}
6989
EXPORT_SYMBOL(unregister_netdevice_many);
6990

L
Linus Torvalds 已提交
6991 6992 6993 6994 6995
/**
 *	unregister_netdev - remove device from the kernel
 *	@dev: device
 *
 *	This function shuts down a device interface and removes it
6996
 *	from the kernel tables.
L
Linus Torvalds 已提交
6997 6998 6999 7000 7001 7002 7003 7004 7005 7006 7007 7008 7009
 *
 *	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);

7010 7011 7012 7013 7014 7015 7016 7017 7018 7019 7020 7021 7022 7023 7024 7025 7026 7027 7028 7029 7030 7031 7032 7033 7034 7035 7036 7037 7038 7039 7040
/**
 *	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;
7041
	if (net_eq(dev_net(dev), net))
7042 7043 7044 7045 7046 7047
		goto out;

	/* Pick the destination device name, and ensure
	 * we can use it in the destination network namespace.
	 */
	err = -EEXIST;
7048
	if (__dev_get_by_name(net, dev->name)) {
7049 7050 7051
		/* We get here if we can't use the current device name */
		if (!pat)
			goto out;
7052
		if (dev_get_valid_name(net, dev, pat) < 0)
7053 7054 7055 7056 7057 7058 7059 7060
			goto out;
	}

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

	/* If device is running close it first. */
7061
	dev_close(dev);
7062 7063 7064 7065 7066 7067 7068 7069 7070 7071 7072 7073

	/* 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.
7074 7075 7076 7077

	   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.
7078 7079
	*/
	call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
7080 7081
	rcu_barrier();
	call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
7082
	rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
7083 7084 7085 7086

	/*
	 *	Flush the unicast and multicast chains
	 */
7087
	dev_uc_flush(dev);
7088
	dev_mc_flush(dev);
7089

7090 7091
	/* Send a netdev-removed uevent to the old namespace */
	kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
7092
	netdev_adjacent_del_links(dev);
7093

7094
	/* Actually switch the network namespace */
7095
	dev_net_set(dev, net);
7096 7097

	/* If there is an ifindex conflict assign a new one */
7098
	if (__dev_get_by_index(net, dev->ifindex))
7099 7100
		dev->ifindex = dev_new_index(net);

7101 7102
	/* Send a netdev-add uevent to the new namespace */
	kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
7103
	netdev_adjacent_add_links(dev);
7104

7105
	/* Fixup kobjects */
7106
	err = device_rename(&dev->dev, dev->name);
7107
	WARN_ON(err);
7108 7109 7110 7111 7112 7113 7114

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

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

7115 7116 7117 7118
	/*
	 *	Prevent userspace races by waiting until the network
	 *	device is fully setup before sending notifications.
	 */
7119
	rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
7120

7121 7122 7123 7124 7125
	synchronize_net();
	err = 0;
out:
	return err;
}
7126
EXPORT_SYMBOL_GPL(dev_change_net_namespace);
7127

L
Linus Torvalds 已提交
7128 7129 7130 7131 7132 7133 7134 7135 7136
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;

7137
	if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
L
Linus Torvalds 已提交
7138 7139 7140 7141 7142 7143 7144 7145 7146 7147 7148 7149 7150 7151 7152 7153
		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. */
7154 7155 7156 7157 7158 7159
	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
7160 7161 7162 7163 7164 7165 7166 7167 7168 7169 7170 7171 7172 7173
	/* 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);
7174
	}
L
Linus Torvalds 已提交
7175 7176 7177 7178 7179

	raise_softirq_irqoff(NET_TX_SOFTIRQ);
	local_irq_enable();

	/* Process offline CPU's input_pkt_queue */
7180
	while ((skb = __skb_dequeue(&oldsd->process_queue))) {
7181
		netif_rx_ni(skb);
7182
		input_queue_head_incr(oldsd);
T
Tom Herbert 已提交
7183
	}
E
Eric Dumazet 已提交
7184
	while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
7185
		netif_rx_ni(skb);
7186 7187
		input_queue_head_incr(oldsd);
	}
L
Linus Torvalds 已提交
7188 7189 7190 7191 7192

	return NOTIFY_OK;
}


7193
/**
7194 7195 7196 7197
 *	netdev_increment_features - increment feature set by one
 *	@all: current feature set
 *	@one: new feature set
 *	@mask: mask feature set
7198 7199
 *
 *	Computes a new feature set after adding a device with feature set
7200 7201
 *	@one to the master device with current feature set @all.  Will not
 *	enable anything that is off in @mask. Returns the new feature set.
7202
 */
7203 7204
netdev_features_t netdev_increment_features(netdev_features_t all,
	netdev_features_t one, netdev_features_t mask)
7205
{
7206 7207 7208
	if (mask & NETIF_F_GEN_CSUM)
		mask |= NETIF_F_ALL_CSUM;
	mask |= NETIF_F_VLAN_CHALLENGED;
7209

7210 7211
	all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
	all &= one | ~NETIF_F_ALL_FOR_ALL;
7212

7213 7214 7215
	/* If one device supports hw checksumming, set for all. */
	if (all & NETIF_F_GEN_CSUM)
		all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
7216 7217 7218

	return all;
}
7219
EXPORT_SYMBOL(netdev_increment_features);
7220

7221
static struct hlist_head * __net_init netdev_create_hash(void)
7222 7223 7224 7225 7226 7227 7228 7229 7230 7231 7232 7233
{
	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;
}

7234
/* Initialize per network namespace state */
7235
static int __net_init netdev_init(struct net *net)
7236
{
7237 7238
	if (net != &init_net)
		INIT_LIST_HEAD(&net->dev_base_head);
7239

7240 7241 7242
	net->dev_name_head = netdev_create_hash();
	if (net->dev_name_head == NULL)
		goto err_name;
7243

7244 7245 7246
	net->dev_index_head = netdev_create_hash();
	if (net->dev_index_head == NULL)
		goto err_idx;
7247 7248

	return 0;
7249 7250 7251 7252 7253

err_idx:
	kfree(net->dev_name_head);
err_name:
	return -ENOMEM;
7254 7255
}

7256 7257 7258 7259 7260 7261
/**
 *	netdev_drivername - network driver for the device
 *	@dev: network device
 *
 *	Determine network driver for device.
 */
7262
const char *netdev_drivername(const struct net_device *dev)
7263
{
7264 7265
	const struct device_driver *driver;
	const struct device *parent;
7266
	const char *empty = "";
7267 7268 7269

	parent = dev->dev.parent;
	if (!parent)
7270
		return empty;
7271 7272 7273

	driver = parent->driver;
	if (driver && driver->name)
7274 7275
		return driver->name;
	return empty;
7276 7277
}

7278 7279
static void __netdev_printk(const char *level, const struct net_device *dev,
			    struct va_format *vaf)
7280
{
7281
	if (dev && dev->dev.parent) {
7282 7283 7284 7285 7286 7287 7288
		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);
7289
	} else if (dev) {
7290 7291
		printk("%s%s%s: %pV",
		       level, netdev_name(dev), netdev_reg_state(dev), vaf);
7292
	} else {
7293
		printk("%s(NULL net_device): %pV", level, vaf);
7294
	}
7295 7296
}

7297 7298
void netdev_printk(const char *level, const struct net_device *dev,
		   const char *format, ...)
7299 7300 7301 7302 7303 7304 7305 7306 7307
{
	struct va_format vaf;
	va_list args;

	va_start(args, format);

	vaf.fmt = format;
	vaf.va = &args;

7308
	__netdev_printk(level, dev, &vaf);
7309

7310 7311 7312 7313 7314
	va_end(args);
}
EXPORT_SYMBOL(netdev_printk);

#define define_netdev_printk_level(func, level)			\
7315
void func(const struct net_device *dev, const char *fmt, ...)	\
7316 7317 7318 7319 7320 7321 7322 7323 7324
{								\
	struct va_format vaf;					\
	va_list args;						\
								\
	va_start(args, fmt);					\
								\
	vaf.fmt = fmt;						\
	vaf.va = &args;						\
								\
7325
	__netdev_printk(level, dev, &vaf);			\
7326
								\
7327 7328 7329 7330 7331 7332 7333 7334 7335 7336 7337 7338
	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);

7339
static void __net_exit netdev_exit(struct net *net)
7340 7341 7342 7343 7344
{
	kfree(net->dev_name_head);
	kfree(net->dev_index_head);
}

7345
static struct pernet_operations __net_initdata netdev_net_ops = {
7346 7347 7348 7349
	.init = netdev_init,
	.exit = netdev_exit,
};

7350
static void __net_exit default_device_exit(struct net *net)
7351
{
7352
	struct net_device *dev, *aux;
7353
	/*
7354
	 * Push all migratable network devices back to the
7355 7356 7357
	 * initial network namespace
	 */
	rtnl_lock();
7358
	for_each_netdev_safe(net, dev, aux) {
7359
		int err;
7360
		char fb_name[IFNAMSIZ];
7361 7362 7363 7364 7365

		/* Ignore unmoveable devices (i.e. loopback) */
		if (dev->features & NETIF_F_NETNS_LOCAL)
			continue;

7366 7367 7368
		/* Leave virtual devices for the generic cleanup */
		if (dev->rtnl_link_ops)
			continue;
7369

L
Lucas De Marchi 已提交
7370
		/* Push remaining network devices to init_net */
7371 7372
		snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
		err = dev_change_net_namespace(dev, &init_net, fb_name);
7373
		if (err) {
7374 7375
			pr_emerg("%s: failed to move %s to init_net: %d\n",
				 __func__, dev->name, err);
7376
			BUG();
7377 7378 7379 7380 7381
		}
	}
	rtnl_unlock();
}

7382 7383 7384 7385 7386 7387 7388
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;
7389
	DEFINE_WAIT_FUNC(wait, woken_wake_function);
7390

7391
	add_wait_queue(&netdev_unregistering_wq, &wait);
7392 7393 7394 7395 7396 7397 7398 7399 7400 7401 7402 7403
	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();
7404 7405

		wait_woken(&wait, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
7406
	}
7407
	remove_wait_queue(&netdev_unregistering_wq, &wait);
7408 7409
}

7410 7411 7412
static void __net_exit default_device_exit_batch(struct list_head *net_list)
{
	/* At exit all network devices most be removed from a network
7413
	 * namespace.  Do this in the reverse order of registration.
7414 7415 7416 7417 7418 7419 7420
	 * 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);

7421 7422 7423 7424 7425 7426 7427 7428 7429 7430 7431 7432
	/* 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);
7433 7434
	list_for_each_entry(net, net_list, exit_list) {
		for_each_netdev_reverse(net, dev) {
7435
			if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink)
7436 7437 7438 7439 7440 7441 7442 7443 7444
				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();
}

7445
static struct pernet_operations __net_initdata default_device_ops = {
7446
	.exit = default_device_exit,
7447
	.exit_batch = default_device_exit_batch,
7448 7449
};

L
Linus Torvalds 已提交
7450 7451 7452 7453 7454 7455 7456 7457 7458 7459 7460 7461 7462 7463 7464 7465 7466 7467 7468 7469
/*
 *	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;

7470
	if (netdev_kobject_init())
L
Linus Torvalds 已提交
7471 7472 7473
		goto out;

	INIT_LIST_HEAD(&ptype_all);
7474
	for (i = 0; i < PTYPE_HASH_SIZE; i++)
L
Linus Torvalds 已提交
7475 7476
		INIT_LIST_HEAD(&ptype_base[i]);

7477 7478
	INIT_LIST_HEAD(&offload_base);

7479 7480
	if (register_pernet_subsys(&netdev_net_ops))
		goto out;
L
Linus Torvalds 已提交
7481 7482 7483 7484 7485

	/*
	 *	Initialise the packet receive queues.
	 */

7486
	for_each_possible_cpu(i) {
E
Eric Dumazet 已提交
7487
		struct softnet_data *sd = &per_cpu(softnet_data, i);
L
Linus Torvalds 已提交
7488

E
Eric Dumazet 已提交
7489
		skb_queue_head_init(&sd->input_pkt_queue);
7490
		skb_queue_head_init(&sd->process_queue);
E
Eric Dumazet 已提交
7491
		INIT_LIST_HEAD(&sd->poll_list);
7492
		sd->output_queue_tailp = &sd->output_queue;
E
Eric Dumazet 已提交
7493
#ifdef CONFIG_RPS
E
Eric Dumazet 已提交
7494 7495 7496
		sd->csd.func = rps_trigger_softirq;
		sd->csd.info = sd;
		sd->cpu = i;
7497
#endif
T
Tom Herbert 已提交
7498

E
Eric Dumazet 已提交
7499 7500
		sd->backlog.poll = process_backlog;
		sd->backlog.weight = weight_p;
L
Linus Torvalds 已提交
7501 7502 7503 7504
	}

	dev_boot_phase = 0;

7505 7506 7507 7508 7509 7510 7511 7512 7513 7514 7515 7516 7517 7518 7519
	/* 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;

7520 7521
	open_softirq(NET_TX_SOFTIRQ, net_tx_action);
	open_softirq(NET_RX_SOFTIRQ, net_rx_action);
L
Linus Torvalds 已提交
7522 7523 7524 7525 7526 7527 7528 7529 7530

	hotcpu_notifier(dev_cpu_callback, 0);
	dst_init();
	rc = 0;
out:
	return rc;
}

subsys_initcall(net_dev_init);