dev.c 186.5 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 < nr_cpu_ids) {
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
		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:
3187
		 *   - Current CPU is unset (>= nr_cpu_ids).
T
Tom Herbert 已提交
3188 3189 3190 3191 3192 3193 3194
		 *   - 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) &&
3195
		    (tcpu >= nr_cpu_ids || !cpu_online(tcpu) ||
T
Tom Herbert 已提交
3196
		     ((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

3202
		if (tcpu < nr_cpu_ids && cpu_online(tcpu)) {
T
Tom Herbert 已提交
3203 3204 3205 3206 3207 3208
			*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
#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;
3243
	unsigned int cpu;
3244 3245 3246 3247 3248 3249

	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);
3250
		if (rflow->filter == filter_id && cpu < nr_cpu_ids &&
3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261 3262
		    ((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 3535
	int result = TC_ACT_OK;
	struct Qdisc *q;
3536

3537
	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
L
Linus Torvalds 已提交
3538

3539
	q = rcu_dereference(rxq->qdisc);
3540
	if (q != &noop_qdisc) {
3541 3542
		if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
			result = qdisc_enqueue_root(skb, q);
3543
	}
3544 3545 3546

	return result;
}
3547

3548 3549 3550 3551
static inline struct sk_buff *handle_ing(struct sk_buff *skb,
					 struct packet_type **pt_prev,
					 int *ret, struct net_device *orig_dev)
{
3552 3553
	struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);

3554
	if (!rxq || rcu_access_pointer(rxq->qdisc) == &noop_qdisc)
3555
		return skb;
L
Linus Torvalds 已提交
3556

3557 3558 3559
	if (*pt_prev) {
		*ret = deliver_skb(skb, *pt_prev, orig_dev);
		*pt_prev = NULL;
L
Linus Torvalds 已提交
3560 3561
	}

3562
	switch (ing_filter(skb, rxq)) {
3563 3564 3565 3566 3567 3568 3569
	case TC_ACT_SHOT:
	case TC_ACT_STOLEN:
		kfree_skb(skb);
		return NULL;
	}

	return skb;
L
Linus Torvalds 已提交
3570 3571 3572
}
#endif

3573 3574 3575 3576
/**
 *	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
3577
 *	@rx_handler_data: data pointer that is used by rx handler
3578
 *
3579
 *	Register a receive handler for a device. This handler will then be
3580 3581 3582 3583
 *	called from __netif_receive_skb. A negative errno code is returned
 *	on a failure.
 *
 *	The caller must hold the rtnl_mutex.
3584 3585
 *
 *	For a general description of rx_handler, see enum rx_handler_result.
3586 3587
 */
int netdev_rx_handler_register(struct net_device *dev,
J
Jiri Pirko 已提交
3588 3589
			       rx_handler_func_t *rx_handler,
			       void *rx_handler_data)
3590 3591 3592 3593 3594 3595
{
	ASSERT_RTNL();

	if (dev->rx_handler)
		return -EBUSY;

3596
	/* Note: rx_handler_data must be set before rx_handler */
J
Jiri Pirko 已提交
3597
	rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3598 3599 3600 3601 3602 3603 3604 3605 3606 3607
	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
3608
 *	Unregister a receive handler from a device.
3609 3610 3611 3612 3613 3614 3615
 *
 *	The caller must hold the rtnl_mutex.
 */
void netdev_rx_handler_unregister(struct net_device *dev)
{

	ASSERT_RTNL();
3616
	RCU_INIT_POINTER(dev->rx_handler, NULL);
3617 3618 3619 3620 3621
	/* 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();
3622
	RCU_INIT_POINTER(dev->rx_handler_data, NULL);
3623 3624 3625
}
EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);

3626 3627 3628 3629 3630 3631 3632
/*
 * 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) {
3633 3634 3635 3636 3637
	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):
3638 3639 3640 3641 3642 3643
		return true;
	default:
		return false;
	}
}

3644
static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
L
Linus Torvalds 已提交
3645 3646
{
	struct packet_type *ptype, *pt_prev;
3647
	rx_handler_func_t *rx_handler;
D
David S. Miller 已提交
3648
	struct net_device *orig_dev;
3649
	bool deliver_exact = false;
L
Linus Torvalds 已提交
3650
	int ret = NET_RX_DROP;
A
Al Viro 已提交
3651
	__be16 type;
L
Linus Torvalds 已提交
3652

3653
	net_timestamp_check(!netdev_tstamp_prequeue, skb);
3654

3655
	trace_netif_receive_skb(skb);
3656

J
Joe Eykholt 已提交
3657
	orig_dev = skb->dev;
3658

3659
	skb_reset_network_header(skb);
3660 3661
	if (!skb_transport_header_was_set(skb))
		skb_reset_transport_header(skb);
3662
	skb_reset_mac_len(skb);
L
Linus Torvalds 已提交
3663 3664 3665 3666 3667

	pt_prev = NULL;

	rcu_read_lock();

3668
another_round:
3669
	skb->skb_iif = skb->dev->ifindex;
3670 3671 3672

	__this_cpu_inc(softnet_data.processed);

P
Patrick McHardy 已提交
3673 3674
	if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
	    skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
3675
		skb = skb_vlan_untag(skb);
3676
		if (unlikely(!skb))
3677
			goto unlock;
3678 3679
	}

L
Linus Torvalds 已提交
3680 3681 3682 3683 3684 3685 3686
#ifdef CONFIG_NET_CLS_ACT
	if (skb->tc_verd & TC_NCLS) {
		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
		goto ncls;
	}
#endif

3687
	if (pfmemalloc)
3688 3689
		goto skip_taps;

L
Linus Torvalds 已提交
3690
	list_for_each_entry_rcu(ptype, &ptype_all, list) {
3691 3692 3693 3694 3695 3696 3697 3698 3699
		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
3700 3701
	}

3702
skip_taps:
L
Linus Torvalds 已提交
3703
#ifdef CONFIG_NET_CLS_ACT
3704 3705 3706 3707 3708 3709 3710
	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
3711 3712
ncls:
#endif
3713
	if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
3714 3715
		goto drop;

3716
	if (skb_vlan_tag_present(skb)) {
3717 3718 3719 3720
		if (pt_prev) {
			ret = deliver_skb(skb, pt_prev, orig_dev);
			pt_prev = NULL;
		}
3721
		if (vlan_do_receive(&skb))
3722 3723
			goto another_round;
		else if (unlikely(!skb))
3724
			goto unlock;
3725 3726
	}

3727
	rx_handler = rcu_dereference(skb->dev->rx_handler);
3728 3729 3730 3731 3732
	if (rx_handler) {
		if (pt_prev) {
			ret = deliver_skb(skb, pt_prev, orig_dev);
			pt_prev = NULL;
		}
3733 3734
		switch (rx_handler(&skb)) {
		case RX_HANDLER_CONSUMED:
3735
			ret = NET_RX_SUCCESS;
3736
			goto unlock;
3737
		case RX_HANDLER_ANOTHER:
3738
			goto another_round;
3739 3740 3741 3742 3743 3744 3745
		case RX_HANDLER_EXACT:
			deliver_exact = true;
		case RX_HANDLER_PASS:
			break;
		default:
			BUG();
		}
3746
	}
L
Linus Torvalds 已提交
3747

3748 3749
	if (unlikely(skb_vlan_tag_present(skb))) {
		if (skb_vlan_tag_get_id(skb))
E
Eric Dumazet 已提交
3750 3751 3752 3753 3754 3755 3756
			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;
	}
3757

3758 3759
	type = skb->protocol;

3760
	/* deliver only exact match when indicated */
3761 3762 3763 3764 3765
	if (likely(!deliver_exact)) {
		deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
				       &ptype_base[ntohs(type) &
						   PTYPE_HASH_MASK]);
	}
3766

3767 3768 3769 3770 3771 3772
	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
3773 3774 3775
	}

	if (pt_prev) {
3776
		if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
3777
			goto drop;
3778 3779
		else
			ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
L
Linus Torvalds 已提交
3780
	} else {
3781
drop:
3782
		atomic_long_inc(&skb->dev->rx_dropped);
L
Linus Torvalds 已提交
3783 3784 3785 3786 3787 3788 3789
		kfree_skb(skb);
		/* Jamal, now you will not able to escape explaining
		 * me how you were going to use this. :-)
		 */
		ret = NET_RX_DROP;
	}

3790
unlock:
L
Linus Torvalds 已提交
3791
	rcu_read_unlock();
3792 3793 3794 3795 3796 3797 3798 3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811 3812 3813 3814 3815 3816
	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
3817 3818
	return ret;
}
T
Tom Herbert 已提交
3819

3820
static int netif_receive_skb_internal(struct sk_buff *skb)
T
Tom Herbert 已提交
3821
{
3822
	net_timestamp_check(netdev_tstamp_prequeue, skb);
E
Eric Dumazet 已提交
3823

3824 3825 3826
	if (skb_defer_rx_timestamp(skb))
		return NET_RX_SUCCESS;

E
Eric Dumazet 已提交
3827
#ifdef CONFIG_RPS
3828
	if (static_key_false(&rps_needed)) {
E
Eric Dumazet 已提交
3829 3830
		struct rps_dev_flow voidflow, *rflow = &voidflow;
		int cpu, ret;
T
Tom Herbert 已提交
3831

E
Eric Dumazet 已提交
3832 3833 3834
		rcu_read_lock();

		cpu = get_rps_cpu(skb->dev, skb, &rflow);
T
Tom Herbert 已提交
3835

E
Eric Dumazet 已提交
3836 3837 3838
		if (cpu >= 0) {
			ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
			rcu_read_unlock();
3839
			return ret;
E
Eric Dumazet 已提交
3840
		}
3841
		rcu_read_unlock();
T
Tom Herbert 已提交
3842
	}
3843
#endif
3844
	return __netif_receive_skb(skb);
T
Tom Herbert 已提交
3845
}
3846 3847 3848 3849 3850 3851 3852 3853 3854 3855 3856 3857 3858 3859 3860 3861

/**
 *	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
 */
3862
int netif_receive_skb_sk(struct sock *sk, struct sk_buff *skb)
3863 3864 3865 3866 3867
{
	trace_netif_receive_skb_entry(skb);

	return netif_receive_skb_internal(skb);
}
3868
EXPORT_SYMBOL(netif_receive_skb_sk);
L
Linus Torvalds 已提交
3869

E
Eric Dumazet 已提交
3870 3871 3872
/* Network device is going away, flush any packets still pending
 * Called with irqs disabled.
 */
3873
static void flush_backlog(void *arg)
3874
{
3875
	struct net_device *dev = arg;
3876
	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
3877 3878
	struct sk_buff *skb, *tmp;

E
Eric Dumazet 已提交
3879
	rps_lock(sd);
3880
	skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
3881
		if (skb->dev == dev) {
E
Eric Dumazet 已提交
3882
			__skb_unlink(skb, &sd->input_pkt_queue);
3883
			kfree_skb(skb);
3884
			input_queue_head_incr(sd);
3885
		}
3886
	}
E
Eric Dumazet 已提交
3887
	rps_unlock(sd);
3888 3889 3890 3891 3892

	skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
		if (skb->dev == dev) {
			__skb_unlink(skb, &sd->process_queue);
			kfree_skb(skb);
3893
			input_queue_head_incr(sd);
3894 3895
		}
	}
3896 3897
}

3898 3899
static int napi_gro_complete(struct sk_buff *skb)
{
3900
	struct packet_offload *ptype;
3901
	__be16 type = skb->protocol;
3902
	struct list_head *head = &offload_base;
3903 3904
	int err = -ENOENT;

3905 3906
	BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));

3907 3908
	if (NAPI_GRO_CB(skb)->count == 1) {
		skb_shinfo(skb)->gso_size = 0;
3909
		goto out;
3910
	}
3911 3912 3913

	rcu_read_lock();
	list_for_each_entry_rcu(ptype, head, list) {
3914
		if (ptype->type != type || !ptype->callbacks.gro_complete)
3915 3916
			continue;

3917
		err = ptype->callbacks.gro_complete(skb, 0);
3918 3919 3920 3921 3922 3923 3924 3925 3926 3927 3928
		break;
	}
	rcu_read_unlock();

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

out:
3929
	return netif_receive_skb_internal(skb);
3930 3931
}

3932 3933 3934 3935 3936
/* 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)
3937
{
3938
	struct sk_buff *skb, *prev = NULL;
3939

3940 3941 3942 3943 3944 3945 3946
	/* 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) {
3947
		skb->next = NULL;
3948 3949 3950 3951 3952

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

		prev = skb->prev;
3953
		napi_gro_complete(skb);
3954
		napi->gro_count--;
3955 3956 3957 3958
	}

	napi->gro_list = NULL;
}
E
Eric Dumazet 已提交
3959
EXPORT_SYMBOL(napi_gro_flush);
3960

E
Eric Dumazet 已提交
3961 3962 3963 3964
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;
3965
	u32 hash = skb_get_hash_raw(skb);
E
Eric Dumazet 已提交
3966 3967 3968 3969

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

3970 3971 3972 3973 3974 3975 3976
		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
3977 3978 3979 3980
		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),
3981
						      skb_mac_header(skb));
E
Eric Dumazet 已提交
3982 3983
		else if (!diffs)
			diffs = memcmp(skb_mac_header(p),
3984
				       skb_mac_header(skb),
E
Eric Dumazet 已提交
3985 3986 3987 3988 3989
				       maclen);
		NAPI_GRO_CB(p)->same_flow = !diffs;
	}
}

3990 3991 3992 3993 3994 3995 3996 3997 3998 3999 4000 4001 4002 4003
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
4004 4005 4006
	}
}

4007 4008 4009 4010 4011 4012 4013 4014 4015 4016 4017 4018 4019 4020 4021 4022 4023 4024 4025 4026 4027
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
4028
static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4029 4030
{
	struct sk_buff **pp = NULL;
4031
	struct packet_offload *ptype;
4032
	__be16 type = skb->protocol;
4033
	struct list_head *head = &offload_base;
H
Herbert Xu 已提交
4034
	int same_flow;
4035
	enum gro_result ret;
4036
	int grow;
4037

4038
	if (!(skb->dev->features & NETIF_F_GRO))
4039 4040
		goto normal;

4041
	if (skb_is_gso(skb) || skb_has_frag_list(skb) || skb->csum_bad)
4042 4043
		goto normal;

E
Eric Dumazet 已提交
4044 4045
	gro_list_prepare(napi, skb);

4046 4047
	rcu_read_lock();
	list_for_each_entry_rcu(ptype, head, list) {
4048
		if (ptype->type != type || !ptype->callbacks.gro_receive)
4049 4050
			continue;

4051
		skb_set_network_header(skb, skb_gro_offset(skb));
4052
		skb_reset_mac_len(skb);
4053 4054
		NAPI_GRO_CB(skb)->same_flow = 0;
		NAPI_GRO_CB(skb)->flush = 0;
H
Herbert Xu 已提交
4055
		NAPI_GRO_CB(skb)->free = 0;
4056
		NAPI_GRO_CB(skb)->udp_mark = 0;
4057
		NAPI_GRO_CB(skb)->gro_remcsum_start = 0;
4058

4059 4060 4061 4062 4063 4064 4065 4066 4067 4068 4069 4070 4071 4072 4073
		/* 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;
		}
4074

4075
		pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
4076 4077 4078 4079 4080 4081 4082
		break;
	}
	rcu_read_unlock();

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

H
Herbert Xu 已提交
4083
	same_flow = NAPI_GRO_CB(skb)->same_flow;
4084
	ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
H
Herbert Xu 已提交
4085

4086 4087 4088 4089 4090 4091
	if (pp) {
		struct sk_buff *nskb = *pp;

		*pp = nskb->next;
		nskb->next = NULL;
		napi_gro_complete(nskb);
4092
		napi->gro_count--;
4093 4094
	}

H
Herbert Xu 已提交
4095
	if (same_flow)
4096 4097
		goto ok;

4098
	if (NAPI_GRO_CB(skb)->flush)
4099 4100
		goto normal;

4101 4102 4103 4104 4105 4106 4107 4108 4109 4110 4111 4112 4113 4114
	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++;
	}
4115
	NAPI_GRO_CB(skb)->count = 1;
4116
	NAPI_GRO_CB(skb)->age = jiffies;
4117
	NAPI_GRO_CB(skb)->last = skb;
4118
	skb_shinfo(skb)->gso_size = skb_gro_len(skb);
4119 4120
	skb->next = napi->gro_list;
	napi->gro_list = skb;
4121
	ret = GRO_HELD;
4122

4123
pull:
4124 4125 4126
	grow = skb_gro_offset(skb) - skb_headlen(skb);
	if (grow > 0)
		gro_pull_from_frag0(skb, grow);
4127
ok:
4128
	return ret;
4129 4130

normal:
4131 4132
	ret = GRO_NORMAL;
	goto pull;
H
Herbert Xu 已提交
4133
}
4134

4135 4136 4137 4138 4139 4140 4141 4142 4143 4144 4145 4146
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;
}
4147
EXPORT_SYMBOL(gro_find_receive_by_type);
4148 4149 4150 4151 4152 4153 4154 4155 4156 4157 4158 4159 4160

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;
}
4161
EXPORT_SYMBOL(gro_find_complete_by_type);
H
Herbert Xu 已提交
4162

R
Rami Rosen 已提交
4163
static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
H
Herbert Xu 已提交
4164
{
4165 4166
	switch (ret) {
	case GRO_NORMAL:
4167
		if (netif_receive_skb_internal(skb))
4168 4169
			ret = GRO_DROP;
		break;
H
Herbert Xu 已提交
4170

4171
	case GRO_DROP:
H
Herbert Xu 已提交
4172 4173
		kfree_skb(skb);
		break;
4174

4175
	case GRO_MERGED_FREE:
4176 4177 4178 4179
		if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
			kmem_cache_free(skbuff_head_cache, skb);
		else
			__kfree_skb(skb);
4180 4181
		break;

4182 4183 4184
	case GRO_HELD:
	case GRO_MERGED:
		break;
H
Herbert Xu 已提交
4185 4186
	}

4187
	return ret;
4188 4189
}

4190
gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4191
{
4192
	trace_napi_gro_receive_entry(skb);
4193

4194 4195
	skb_gro_reset_offset(skb);

E
Eric Dumazet 已提交
4196
	return napi_skb_finish(dev_gro_receive(napi, skb), skb);
4197 4198 4199
}
EXPORT_SYMBOL(napi_gro_receive);

S
stephen hemminger 已提交
4200
static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
4201
{
4202 4203 4204 4205
	if (unlikely(skb->pfmemalloc)) {
		consume_skb(skb);
		return;
	}
4206
	__skb_pull(skb, skb_headlen(skb));
4207 4208
	/* restore the reserve we had after netdev_alloc_skb_ip_align() */
	skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
4209
	skb->vlan_tci = 0;
H
Herbert Xu 已提交
4210
	skb->dev = napi->dev;
A
Andy Gospodarek 已提交
4211
	skb->skb_iif = 0;
4212 4213
	skb->encapsulation = 0;
	skb_shinfo(skb)->gso_type = 0;
4214
	skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
4215 4216 4217 4218

	napi->skb = skb;
}

4219
struct sk_buff *napi_get_frags(struct napi_struct *napi)
H
Herbert Xu 已提交
4220 4221 4222 4223
{
	struct sk_buff *skb = napi->skb;

	if (!skb) {
4224
		skb = napi_alloc_skb(napi, GRO_MAX_HEAD);
E
Eric Dumazet 已提交
4225
		napi->skb = skb;
4226
	}
4227 4228
	return skb;
}
4229
EXPORT_SYMBOL(napi_get_frags);
4230

4231 4232 4233
static gro_result_t napi_frags_finish(struct napi_struct *napi,
				      struct sk_buff *skb,
				      gro_result_t ret)
4234
{
4235 4236
	switch (ret) {
	case GRO_NORMAL:
4237 4238 4239 4240
	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))
4241
			ret = GRO_DROP;
4242
		break;
H
Herbert Xu 已提交
4243

4244 4245 4246 4247
	case GRO_DROP:
	case GRO_MERGED_FREE:
		napi_reuse_skb(napi, skb);
		break;
4248 4249 4250

	case GRO_MERGED:
		break;
4251
	}
H
Herbert Xu 已提交
4252

4253
	return ret;
H
Herbert Xu 已提交
4254
}
4255

4256 4257 4258 4259
/* 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
4260
static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4261 4262
{
	struct sk_buff *skb = napi->skb;
4263 4264
	const struct ethhdr *eth;
	unsigned int hlen = sizeof(*eth);
4265 4266 4267

	napi->skb = NULL;

4268 4269 4270 4271 4272 4273 4274 4275 4276 4277 4278 4279 4280 4281
	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;
4282
	}
4283 4284 4285 4286 4287 4288 4289 4290
	__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;
4291 4292 4293 4294

	return skb;
}

4295
gro_result_t napi_gro_frags(struct napi_struct *napi)
4296
{
4297
	struct sk_buff *skb = napi_frags_skb(napi);
4298 4299

	if (!skb)
4300
		return GRO_DROP;
4301

4302 4303
	trace_napi_gro_frags_entry(skb);

E
Eric Dumazet 已提交
4304
	return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4305
}
H
Herbert Xu 已提交
4306 4307
EXPORT_SYMBOL(napi_gro_frags);

T
Tom Herbert 已提交
4308 4309 4310 4311 4312 4313 4314 4315 4316 4317 4318 4319 4320 4321 4322 4323 4324 4325 4326 4327 4328 4329 4330 4331 4332
/* 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);

4333
/*
4334
 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
4335 4336 4337 4338 4339 4340 4341 4342 4343 4344 4345 4346 4347 4348 4349 4350 4351
 * 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))
4352
				smp_call_function_single_async(remsd->cpu,
4353
							   &remsd->csd);
4354 4355 4356 4357 4358 4359 4360
			remsd = next;
		}
	} else
#endif
		local_irq_enable();
}

E
Eric Dumazet 已提交
4361 4362 4363 4364 4365 4366 4367 4368 4369
static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
{
#ifdef CONFIG_RPS
	return sd->rps_ipi_list != NULL;
#else
	return false;
#endif
}

4370
static int process_backlog(struct napi_struct *napi, int quota)
L
Linus Torvalds 已提交
4371 4372
{
	int work = 0;
E
Eric Dumazet 已提交
4373
	struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
L
Linus Torvalds 已提交
4374

4375 4376 4377
	/* Check if we have pending ipi, its better to send them now,
	 * not waiting net_rx_action() end.
	 */
E
Eric Dumazet 已提交
4378
	if (sd_has_rps_ipi_waiting(sd)) {
4379 4380 4381
		local_irq_disable();
		net_rps_action_and_irq_enable(sd);
	}
E
Eric Dumazet 已提交
4382

4383
	napi->weight = weight_p;
4384
	local_irq_disable();
4385
	while (1) {
L
Linus Torvalds 已提交
4386
		struct sk_buff *skb;
4387 4388 4389 4390 4391

		while ((skb = __skb_dequeue(&sd->process_queue))) {
			local_irq_enable();
			__netif_receive_skb(skb);
			local_irq_disable();
4392 4393 4394 4395 4396
			input_queue_head_incr(sd);
			if (++work >= quota) {
				local_irq_enable();
				return work;
			}
4397
		}
L
Linus Torvalds 已提交
4398

E
Eric Dumazet 已提交
4399
		rps_lock(sd);
4400
		if (skb_queue_empty(&sd->input_pkt_queue)) {
E
Eric Dumazet 已提交
4401 4402 4403
			/*
			 * Inline a custom version of __napi_complete().
			 * only current cpu owns and manipulates this napi,
4404 4405 4406
			 * 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
4407 4408 4409
			 * and we dont need an smp_mb() memory barrier.
			 */
			napi->state = 0;
4410
			rps_unlock(sd);
E
Eric Dumazet 已提交
4411

4412
			break;
4413
		}
4414 4415 4416

		skb_queue_splice_tail_init(&sd->input_pkt_queue,
					   &sd->process_queue);
E
Eric Dumazet 已提交
4417
		rps_unlock(sd);
4418 4419
	}
	local_irq_enable();
L
Linus Torvalds 已提交
4420

4421 4422
	return work;
}
L
Linus Torvalds 已提交
4423

4424 4425
/**
 * __napi_schedule - schedule for receive
4426
 * @n: entry to schedule
4427
 *
4428 4429
 * The entry's receive function will be scheduled to run.
 * Consider using __napi_schedule_irqoff() if hard irqs are masked.
4430
 */
H
Harvey Harrison 已提交
4431
void __napi_schedule(struct napi_struct *n)
4432 4433
{
	unsigned long flags;
L
Linus Torvalds 已提交
4434

4435
	local_irq_save(flags);
4436
	____napi_schedule(this_cpu_ptr(&softnet_data), n);
4437
	local_irq_restore(flags);
L
Linus Torvalds 已提交
4438
}
4439 4440
EXPORT_SYMBOL(__napi_schedule);

4441 4442 4443 4444 4445 4446 4447 4448 4449 4450 4451 4452
/**
 * __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);

4453 4454 4455 4456
void __napi_complete(struct napi_struct *n)
{
	BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));

E
Eric Dumazet 已提交
4457
	list_del_init(&n->poll_list);
4458
	smp_mb__before_atomic();
4459 4460 4461 4462
	clear_bit(NAPI_STATE_SCHED, &n->state);
}
EXPORT_SYMBOL(__napi_complete);

4463
void napi_complete_done(struct napi_struct *n, int work_done)
4464 4465 4466 4467 4468 4469 4470 4471 4472 4473
{
	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;

4474 4475
	if (n->gro_list) {
		unsigned long timeout = 0;
E
Eric Dumazet 已提交
4476

4477 4478 4479 4480 4481 4482 4483 4484 4485
		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
4486 4487 4488 4489 4490 4491 4492 4493
	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);
	}
4494
}
4495
EXPORT_SYMBOL(napi_complete_done);
4496

E
Eliezer Tamir 已提交
4497 4498 4499 4500 4501 4502 4503 4504 4505 4506 4507 4508 4509 4510 4511 4512 4513 4514 4515 4516 4517 4518 4519 4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531 4532 4533 4534 4535 4536 4537 4538 4539 4540 4541 4542 4543 4544 4545 4546 4547 4548
/* 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);

4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559
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;
}

4560 4561 4562 4563
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);
4564 4565
	hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED);
	napi->timer.function = napi_watchdog;
4566
	napi->gro_count = 0;
4567
	napi->gro_list = NULL;
H
Herbert Xu 已提交
4568
	napi->skb = NULL;
4569
	napi->poll = poll;
E
Eric Dumazet 已提交
4570 4571 4572
	if (weight > NAPI_POLL_WEIGHT)
		pr_err_once("netif_napi_add() called with weight %d on device %s\n",
			    weight, dev->name);
4573 4574 4575
	napi->weight = weight;
	list_add(&napi->dev_list, &dev->napi_list);
	napi->dev = dev;
H
Herbert Xu 已提交
4576
#ifdef CONFIG_NETPOLL
4577 4578 4579 4580 4581 4582 4583
	spin_lock_init(&napi->poll_lock);
	napi->poll_owner = -1;
#endif
	set_bit(NAPI_STATE_SCHED, &napi->state);
}
EXPORT_SYMBOL(netif_napi_add);

4584 4585 4586 4587 4588 4589 4590 4591 4592 4593 4594 4595 4596 4597
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);

4598 4599
void netif_napi_del(struct napi_struct *napi)
{
4600
	list_del_init(&napi->dev_list);
4601
	napi_free_frags(napi);
4602

E
Eric Dumazet 已提交
4603
	kfree_skb_list(napi->gro_list);
4604
	napi->gro_list = NULL;
4605
	napi->gro_count = 0;
4606 4607 4608
}
EXPORT_SYMBOL(netif_napi_del);

4609 4610 4611 4612 4613 4614 4615 4616 4617 4618 4619 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
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);
	}

4654 4655 4656 4657 4658 4659 4660 4661 4662
	/* 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;
	}

4663 4664 4665 4666 4667 4668 4669 4670
	list_add_tail(&n->poll_list, repoll);

out_unlock:
	netpoll_poll_unlock(have);

	return work;
}

L
Linus Torvalds 已提交
4671 4672
static void net_rx_action(struct softirq_action *h)
{
4673
	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
4674
	unsigned long time_limit = jiffies + 2;
4675
	int budget = netdev_budget;
E
Eric Dumazet 已提交
4676 4677
	LIST_HEAD(list);
	LIST_HEAD(repoll);
4678

L
Linus Torvalds 已提交
4679
	local_irq_disable();
E
Eric Dumazet 已提交
4680 4681
	list_splice_init(&sd->poll_list, &list);
	local_irq_enable();
L
Linus Torvalds 已提交
4682

H
Herbert Xu 已提交
4683
	for (;;) {
4684
		struct napi_struct *n;
L
Linus Torvalds 已提交
4685

H
Herbert Xu 已提交
4686 4687 4688 4689 4690 4691
		if (list_empty(&list)) {
			if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll))
				return;
			break;
		}

4692 4693 4694
		n = list_first_entry(&list, struct napi_struct, poll_list);
		budget -= napi_poll(n, &repoll);

E
Eric Dumazet 已提交
4695
		/* If softirq window is exhausted then punt.
4696 4697
		 * Allow this to run for 2 jiffies since which will allow
		 * an average latency of 1.5/HZ.
4698
		 */
H
Herbert Xu 已提交
4699 4700 4701 4702 4703
		if (unlikely(budget <= 0 ||
			     time_after_eq(jiffies, time_limit))) {
			sd->time_squeeze++;
			break;
		}
L
Linus Torvalds 已提交
4704
	}
E
Eric Dumazet 已提交
4705 4706 4707 4708 4709 4710 4711 4712 4713

	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);

4714
	net_rps_action_and_irq_enable(sd);
L
Linus Torvalds 已提交
4715 4716
}

4717
struct netdev_adjacent {
J
Jiri Pirko 已提交
4718
	struct net_device *dev;
4719 4720

	/* upper master flag, there can only be one master device per list */
J
Jiri Pirko 已提交
4721
	bool master;
4722 4723 4724 4725

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

4726 4727 4728
	/* private field for the users */
	void *private;

J
Jiri Pirko 已提交
4729 4730 4731 4732
	struct list_head list;
	struct rcu_head rcu;
};

4733 4734
static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
						 struct net_device *adj_dev,
4735
						 struct list_head *adj_list)
J
Jiri Pirko 已提交
4736
{
4737 4738
	struct netdev_adjacent *adj;

4739
	list_for_each_entry(adj, adj_list, list) {
4740 4741
		if (adj->dev == adj_dev)
			return adj;
J
Jiri Pirko 已提交
4742 4743 4744 4745 4746 4747 4748 4749 4750 4751 4752 4753 4754 4755 4756 4757 4758 4759
	}
	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();

4760
	return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper);
J
Jiri Pirko 已提交
4761 4762 4763 4764 4765 4766 4767 4768 4769 4770
}
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
4771
static bool netdev_has_any_upper_dev(struct net_device *dev)
J
Jiri Pirko 已提交
4772 4773 4774
{
	ASSERT_RTNL();

4775
	return !list_empty(&dev->all_adj_list.upper);
J
Jiri Pirko 已提交
4776 4777 4778 4779 4780 4781 4782 4783 4784 4785 4786
}

/**
 * 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)
{
4787
	struct netdev_adjacent *upper;
J
Jiri Pirko 已提交
4788 4789 4790

	ASSERT_RTNL();

4791
	if (list_empty(&dev->adj_list.upper))
J
Jiri Pirko 已提交
4792 4793
		return NULL;

4794
	upper = list_first_entry(&dev->adj_list.upper,
4795
				 struct netdev_adjacent, list);
J
Jiri Pirko 已提交
4796 4797 4798 4799 4800 4801
	if (likely(upper->master))
		return upper->dev;
	return NULL;
}
EXPORT_SYMBOL(netdev_master_upper_dev_get);

4802 4803 4804 4805 4806 4807 4808 4809 4810 4811
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);

4812 4813 4814 4815 4816 4817 4818 4819 4820 4821 4822 4823 4824 4825 4826 4827 4828 4829 4830 4831 4832 4833 4834 4835 4836 4837
/**
 * 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);

4838 4839
/**
 * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
4840 4841 4842 4843 4844 4845
 * @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.
 */
4846 4847
struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
						     struct list_head **iter)
4848 4849 4850
{
	struct netdev_adjacent *upper;

4851
	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
4852 4853 4854

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

4855
	if (&upper->list == &dev->all_adj_list.upper)
4856 4857 4858 4859 4860 4861
		return NULL;

	*iter = &upper->list;

	return upper->dev;
}
4862
EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
4863

4864 4865 4866 4867 4868 4869 4870 4871 4872 4873 4874 4875 4876 4877 4878 4879 4880 4881 4882 4883 4884
/**
 * 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;

4885
	*iter = lower->list.next;
4886 4887 4888 4889 4890 4891 4892 4893 4894 4895 4896 4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908 4909 4910 4911 4912

	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;

4913
	*iter = &lower->list;
4914 4915 4916 4917 4918

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

4919 4920 4921 4922 4923 4924 4925 4926 4927 4928 4929 4930 4931 4932 4933 4934 4935 4936 4937 4938 4939 4940 4941 4942 4943 4944
/**
 * 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);

4945 4946 4947 4948 4949 4950 4951 4952 4953 4954 4955 4956 4957 4958 4959 4960 4961 4962 4963 4964 4965
/**
 * 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
4966 4967 4968 4969 4970 4971 4972 4973 4974
/**
 * 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)
{
4975
	struct netdev_adjacent *upper;
J
Jiri Pirko 已提交
4976

4977
	upper = list_first_or_null_rcu(&dev->adj_list.upper,
4978
				       struct netdev_adjacent, list);
J
Jiri Pirko 已提交
4979 4980 4981 4982 4983 4984
	if (upper && likely(upper->master))
		return upper->dev;
	return NULL;
}
EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);

4985
static int netdev_adjacent_sysfs_add(struct net_device *dev,
4986 4987 4988 4989 4990 4991 4992 4993 4994
			      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);
}
4995
static void netdev_adjacent_sysfs_del(struct net_device *dev,
4996 4997 4998 4999 5000 5001 5002 5003 5004
			       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);
}

5005 5006 5007 5008 5009 5010 5011 5012
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));
}
5013

5014 5015
static int __netdev_adjacent_dev_insert(struct net_device *dev,
					struct net_device *adj_dev,
5016
					struct list_head *dev_list,
5017
					void *private, bool master)
5018 5019
{
	struct netdev_adjacent *adj;
5020
	int ret;
5021

5022
	adj = __netdev_find_adj(dev, adj_dev, dev_list);
5023 5024 5025 5026 5027 5028 5029 5030 5031 5032 5033 5034 5035

	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;
5036
	adj->private = private;
5037
	dev_hold(adj_dev);
5038 5039 5040

	pr_debug("dev_hold for %s, because of link added from %s to %s\n",
		 adj_dev->name, dev->name, adj_dev->name);
5041

5042
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
5043
		ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
5044 5045 5046 5047
		if (ret)
			goto free_adj;
	}

5048
	/* Ensure that master link is always the first item in list. */
5049 5050 5051 5052
	if (master) {
		ret = sysfs_create_link(&(dev->dev.kobj),
					&(adj_dev->dev.kobj), "master");
		if (ret)
5053
			goto remove_symlinks;
5054

5055
		list_add_rcu(&adj->list, dev_list);
5056
	} else {
5057
		list_add_tail_rcu(&adj->list, dev_list);
5058
	}
5059 5060

	return 0;
5061

5062
remove_symlinks:
5063
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
5064
		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
5065 5066
free_adj:
	kfree(adj);
5067
	dev_put(adj_dev);
5068 5069

	return ret;
5070 5071
}

S
stephen hemminger 已提交
5072 5073 5074
static void __netdev_adjacent_dev_remove(struct net_device *dev,
					 struct net_device *adj_dev,
					 struct list_head *dev_list)
5075 5076 5077
{
	struct netdev_adjacent *adj;

5078
	adj = __netdev_find_adj(dev, adj_dev, dev_list);
5079

5080 5081 5082
	if (!adj) {
		pr_err("tried to remove device %s from %s\n",
		       dev->name, adj_dev->name);
5083
		BUG();
5084
	}
5085 5086

	if (adj->ref_nr > 1) {
5087 5088
		pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name,
			 adj->ref_nr-1);
5089 5090 5091 5092
		adj->ref_nr--;
		return;
	}

5093 5094 5095
	if (adj->master)
		sysfs_remove_link(&(dev->dev.kobj), "master");

5096
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
5097
		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
5098

5099
	list_del_rcu(&adj->list);
5100 5101
	pr_debug("dev_put for %s, because link removed from %s to %s\n",
		 adj_dev->name, dev->name, adj_dev->name);
5102 5103 5104 5105
	dev_put(adj_dev);
	kfree_rcu(adj, rcu);
}

S
stephen hemminger 已提交
5106 5107 5108 5109 5110
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)
5111 5112 5113
{
	int ret;

5114 5115
	ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, private,
					   master);
5116 5117 5118
	if (ret)
		return ret;

5119 5120
	ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, private,
					   false);
5121
	if (ret) {
5122
		__netdev_adjacent_dev_remove(dev, upper_dev, up_list);
5123 5124 5125 5126 5127 5128
		return ret;
	}

	return 0;
}

S
stephen hemminger 已提交
5129 5130
static int __netdev_adjacent_dev_link(struct net_device *dev,
				      struct net_device *upper_dev)
5131
{
5132 5133 5134
	return __netdev_adjacent_dev_link_lists(dev, upper_dev,
						&dev->all_adj_list.upper,
						&upper_dev->all_adj_list.lower,
5135
						NULL, false);
5136 5137
}

S
stephen hemminger 已提交
5138 5139 5140 5141
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)
5142
{
5143 5144
	__netdev_adjacent_dev_remove(dev, upper_dev, up_list);
	__netdev_adjacent_dev_remove(upper_dev, dev, down_list);
5145 5146
}

S
stephen hemminger 已提交
5147 5148
static void __netdev_adjacent_dev_unlink(struct net_device *dev,
					 struct net_device *upper_dev)
5149
{
5150 5151 5152 5153 5154
	__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
5155 5156 5157
static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
						struct net_device *upper_dev,
						void *private, bool master)
5158 5159 5160 5161 5162 5163 5164 5165 5166
{
	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,
5167
					       private, master);
5168 5169 5170 5171 5172 5173
	if (ret) {
		__netdev_adjacent_dev_unlink(dev, upper_dev);
		return ret;
	}

	return 0;
5174 5175
}

S
stephen hemminger 已提交
5176 5177
static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
						   struct net_device *upper_dev)
5178 5179 5180 5181 5182 5183
{
	__netdev_adjacent_dev_unlink(dev, upper_dev);
	__netdev_adjacent_dev_unlink_lists(dev, upper_dev,
					   &dev->adj_list.upper,
					   &upper_dev->adj_list.lower);
}
5184

J
Jiri Pirko 已提交
5185
static int __netdev_upper_dev_link(struct net_device *dev,
5186 5187
				   struct net_device *upper_dev, bool master,
				   void *private)
J
Jiri Pirko 已提交
5188
{
5189 5190
	struct netdev_adjacent *i, *j, *to_i, *to_j;
	int ret = 0;
J
Jiri Pirko 已提交
5191 5192 5193 5194 5195 5196 5197

	ASSERT_RTNL();

	if (dev == upper_dev)
		return -EBUSY;

	/* To prevent loops, check if dev is not upper device to upper_dev. */
5198
	if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper))
J
Jiri Pirko 已提交
5199 5200
		return -EBUSY;

5201
	if (__netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper))
J
Jiri Pirko 已提交
5202 5203 5204 5205 5206
		return -EEXIST;

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

5207 5208
	ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private,
						   master);
5209 5210
	if (ret)
		return ret;
J
Jiri Pirko 已提交
5211

5212
	/* Now that we linked these devs, make all the upper_dev's
5213
	 * all_adj_list.upper visible to every dev's all_adj_list.lower an
5214 5215 5216
	 * versa, and don't forget the devices itself. All of these
	 * links are non-neighbours.
	 */
5217 5218 5219 5220
	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);
5221 5222 5223 5224 5225 5226 5227
			ret = __netdev_adjacent_dev_link(i->dev, j->dev);
			if (ret)
				goto rollback_mesh;
		}
	}

	/* add dev to every upper_dev's upper device */
5228 5229 5230
	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);
5231 5232 5233 5234 5235 5236
		ret = __netdev_adjacent_dev_link(dev, i->dev);
		if (ret)
			goto rollback_upper_mesh;
	}

	/* add upper_dev to every dev's lower device */
5237 5238 5239
	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);
5240 5241 5242 5243
		ret = __netdev_adjacent_dev_link(i->dev, upper_dev);
		if (ret)
			goto rollback_lower_mesh;
	}
J
Jiri Pirko 已提交
5244

5245
	call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
J
Jiri Pirko 已提交
5246
	return 0;
5247 5248 5249

rollback_lower_mesh:
	to_i = i;
5250
	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
5251 5252 5253 5254 5255 5256 5257 5258 5259
		if (i == to_i)
			break;
		__netdev_adjacent_dev_unlink(i->dev, upper_dev);
	}

	i = NULL;

rollback_upper_mesh:
	to_i = i;
5260
	list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
5261 5262 5263 5264 5265 5266 5267 5268 5269 5270
		if (i == to_i)
			break;
		__netdev_adjacent_dev_unlink(dev, i->dev);
	}

	i = j = NULL;

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

5281
	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5282 5283

	return ret;
J
Jiri Pirko 已提交
5284 5285 5286 5287 5288 5289 5290 5291 5292 5293 5294 5295 5296 5297 5298
}

/**
 * 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)
{
5299
	return __netdev_upper_dev_link(dev, upper_dev, false, NULL);
J
Jiri Pirko 已提交
5300 5301 5302 5303 5304 5305 5306 5307 5308 5309 5310 5311 5312 5313 5314 5315 5316
}
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)
{
5317
	return __netdev_upper_dev_link(dev, upper_dev, true, NULL);
J
Jiri Pirko 已提交
5318 5319 5320
}
EXPORT_SYMBOL(netdev_master_upper_dev_link);

5321 5322 5323 5324 5325 5326 5327 5328
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
5329 5330 5331 5332 5333 5334 5335 5336 5337 5338 5339
/**
 * 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)
{
5340
	struct netdev_adjacent *i, *j;
J
Jiri Pirko 已提交
5341 5342
	ASSERT_RTNL();

5343
	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5344 5345 5346 5347 5348

	/* 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.
	 */
5349 5350
	list_for_each_entry(i, &dev->all_adj_list.lower, list)
		list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
5351 5352 5353 5354 5355
			__netdev_adjacent_dev_unlink(i->dev, j->dev);

	/* remove also the devices itself from lower/upper device
	 * list
	 */
5356
	list_for_each_entry(i, &dev->all_adj_list.lower, list)
5357 5358
		__netdev_adjacent_dev_unlink(i->dev, upper_dev);

5359
	list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
5360 5361
		__netdev_adjacent_dev_unlink(dev, i->dev);

5362
	call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
J
Jiri Pirko 已提交
5363 5364 5365
}
EXPORT_SYMBOL(netdev_upper_dev_unlink);

5366 5367 5368
/**
 * netdev_bonding_info_change - Dispatch event about slave change
 * @dev: device
5369
 * @bonding_info: info to dispatch
5370 5371 5372 5373 5374 5375 5376 5377 5378 5379 5380 5381 5382 5383 5384 5385
 *
 * 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
5386
static void netdev_adjacent_add_links(struct net_device *dev)
5387 5388 5389 5390 5391 5392 5393 5394 5395 5396 5397 5398 5399 5400 5401 5402 5403 5404 5405 5406 5407 5408 5409 5410
{
	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
5411
static void netdev_adjacent_del_links(struct net_device *dev)
5412 5413 5414 5415 5416 5417 5418 5419 5420 5421 5422 5423 5424 5425 5426 5427 5428 5429 5430 5431 5432 5433 5434 5435
{
	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);
	}
}

5436
void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
5437
{
5438
	struct netdev_adjacent *iter;
5439

5440 5441
	struct net *net = dev_net(dev);

5442
	list_for_each_entry(iter, &dev->adj_list.upper, list) {
5443 5444
		if (!net_eq(net,dev_net(iter->dev)))
			continue;
5445 5446 5447 5448 5449
		netdev_adjacent_sysfs_del(iter->dev, oldname,
					  &iter->dev->adj_list.lower);
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.lower);
	}
5450

5451
	list_for_each_entry(iter, &dev->adj_list.lower, list) {
5452 5453
		if (!net_eq(net,dev_net(iter->dev)))
			continue;
5454 5455 5456 5457 5458
		netdev_adjacent_sysfs_del(iter->dev, oldname,
					  &iter->dev->adj_list.upper);
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.upper);
	}
5459 5460 5461 5462 5463 5464 5465 5466 5467 5468 5469 5470 5471 5472 5473 5474 5475
}

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);

5476 5477 5478 5479 5480 5481 5482 5483 5484 5485 5486 5487 5488 5489 5490 5491 5492 5493 5494 5495 5496 5497 5498 5499

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);

5500 5501
static void dev_change_rx_flags(struct net_device *dev, int flags)
{
5502 5503
	const struct net_device_ops *ops = dev->netdev_ops;

5504
	if (ops->ndo_change_rx_flags)
5505
		ops->ndo_change_rx_flags(dev, flags);
5506 5507
}

5508
static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
L
Linus Torvalds 已提交
5509
{
5510
	unsigned int old_flags = dev->flags;
5511 5512
	kuid_t uid;
	kgid_t gid;
L
Linus Torvalds 已提交
5513

5514 5515
	ASSERT_RTNL();

5516 5517 5518 5519 5520 5521 5522 5523 5524 5525 5526
	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;
5527 5528
			pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
				dev->name);
5529 5530 5531
			return -EOVERFLOW;
		}
	}
5532
	if (dev->flags != old_flags) {
5533 5534 5535
		pr_info("device %s %s promiscuous mode\n",
			dev->name,
			dev->flags & IFF_PROMISC ? "entered" : "left");
5536 5537
		if (audit_enabled) {
			current_uid_gid(&uid, &gid);
5538 5539 5540 5541 5542
			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),
5543
				from_kuid(&init_user_ns, audit_get_loginuid(current)),
5544 5545
				from_kuid(&init_user_ns, uid),
				from_kgid(&init_user_ns, gid),
5546
				audit_get_sessionid(current));
5547
		}
5548

5549
		dev_change_rx_flags(dev, IFF_PROMISC);
L
Linus Torvalds 已提交
5550
	}
5551 5552
	if (notify)
		__dev_notify_flags(dev, old_flags, IFF_PROMISC);
5553
	return 0;
L
Linus Torvalds 已提交
5554 5555
}

5556 5557 5558 5559 5560 5561 5562 5563 5564
/**
 *	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.
5565
 *	Return 0 if successful or a negative errno code on error.
5566
 */
5567
int dev_set_promiscuity(struct net_device *dev, int inc)
5568
{
5569
	unsigned int old_flags = dev->flags;
5570
	int err;
5571

5572
	err = __dev_set_promiscuity(dev, inc, true);
5573
	if (err < 0)
5574
		return err;
5575 5576
	if (dev->flags != old_flags)
		dev_set_rx_mode(dev);
5577
	return err;
5578
}
E
Eric Dumazet 已提交
5579
EXPORT_SYMBOL(dev_set_promiscuity);
5580

5581
static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
L
Linus Torvalds 已提交
5582
{
5583
	unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
L
Linus Torvalds 已提交
5584

5585 5586
	ASSERT_RTNL();

L
Linus Torvalds 已提交
5587
	dev->flags |= IFF_ALLMULTI;
5588 5589 5590 5591 5592 5593 5594 5595 5596 5597
	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;
5598 5599
			pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
				dev->name);
5600 5601 5602
			return -EOVERFLOW;
		}
	}
5603
	if (dev->flags ^ old_flags) {
5604
		dev_change_rx_flags(dev, IFF_ALLMULTI);
5605
		dev_set_rx_mode(dev);
5606 5607 5608
		if (notify)
			__dev_notify_flags(dev, old_flags,
					   dev->gflags ^ old_gflags);
5609
	}
5610
	return 0;
5611
}
5612 5613 5614 5615 5616 5617 5618 5619 5620 5621 5622 5623 5624 5625 5626 5627 5628 5629

/**
 *	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
5630
EXPORT_SYMBOL(dev_set_allmulti);
5631 5632 5633 5634

/*
 *	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
5635
 *	filtering it is put in promiscuous mode while unicast addresses
5636 5637 5638 5639
 *	are present.
 */
void __dev_set_rx_mode(struct net_device *dev)
{
5640 5641
	const struct net_device_ops *ops = dev->netdev_ops;

5642 5643 5644 5645 5646
	/* dev_open will call this function so the list will stay sane. */
	if (!(dev->flags&IFF_UP))
		return;

	if (!netif_device_present(dev))
5647
		return;
5648

5649
	if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
5650 5651 5652
		/* Unicast addresses changes may only happen under the rtnl,
		 * therefore calling __dev_set_promiscuity here is safe.
		 */
5653
		if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
5654
			__dev_set_promiscuity(dev, 1, false);
5655
			dev->uc_promisc = true;
5656
		} else if (netdev_uc_empty(dev) && dev->uc_promisc) {
5657
			__dev_set_promiscuity(dev, -1, false);
5658
			dev->uc_promisc = false;
5659 5660
		}
	}
5661 5662 5663

	if (ops->ndo_set_rx_mode)
		ops->ndo_set_rx_mode(dev);
5664 5665 5666 5667
}

void dev_set_rx_mode(struct net_device *dev)
{
5668
	netif_addr_lock_bh(dev);
5669
	__dev_set_rx_mode(dev);
5670
	netif_addr_unlock_bh(dev);
L
Linus Torvalds 已提交
5671 5672
}

5673 5674 5675 5676 5677 5678
/**
 *	dev_get_flags - get flags reported to userspace
 *	@dev: device
 *
 *	Get the combination of flag bits exported through APIs to userspace.
 */
5679
unsigned int dev_get_flags(const struct net_device *dev)
L
Linus Torvalds 已提交
5680
{
5681
	unsigned int flags;
L
Linus Torvalds 已提交
5682 5683 5684

	flags = (dev->flags & ~(IFF_PROMISC |
				IFF_ALLMULTI |
S
Stefan Rompf 已提交
5685 5686 5687
				IFF_RUNNING |
				IFF_LOWER_UP |
				IFF_DORMANT)) |
L
Linus Torvalds 已提交
5688 5689 5690
		(dev->gflags & (IFF_PROMISC |
				IFF_ALLMULTI));

S
Stefan Rompf 已提交
5691 5692 5693 5694 5695 5696 5697 5698
	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
5699 5700 5701

	return flags;
}
E
Eric Dumazet 已提交
5702
EXPORT_SYMBOL(dev_get_flags);
L
Linus Torvalds 已提交
5703

5704
int __dev_change_flags(struct net_device *dev, unsigned int flags)
L
Linus Torvalds 已提交
5705
{
5706
	unsigned int old_flags = dev->flags;
5707
	int ret;
L
Linus Torvalds 已提交
5708

5709 5710
	ASSERT_RTNL();

L
Linus Torvalds 已提交
5711 5712 5713 5714 5715 5716 5717 5718 5719 5720 5721 5722 5723 5724
	/*
	 *	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.
	 */

5725 5726
	if ((old_flags ^ flags) & IFF_MULTICAST)
		dev_change_rx_flags(dev, IFF_MULTICAST);
5727

5728
	dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
5729 5730 5731 5732 5733 5734 5735 5736

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

	ret = 0;
5737
	if ((old_flags ^ flags) & IFF_UP)
5738
		ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
L
Linus Torvalds 已提交
5739 5740

	if ((flags ^ dev->gflags) & IFF_PROMISC) {
E
Eric Dumazet 已提交
5741
		int inc = (flags & IFF_PROMISC) ? 1 : -1;
5742
		unsigned int old_flags = dev->flags;
E
Eric Dumazet 已提交
5743

L
Linus Torvalds 已提交
5744
		dev->gflags ^= IFF_PROMISC;
5745 5746 5747 5748

		if (__dev_set_promiscuity(dev, inc, false) >= 0)
			if (dev->flags != old_flags)
				dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
5749 5750 5751 5752 5753 5754 5755
	}

	/* 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
5756 5757
		int inc = (flags & IFF_ALLMULTI) ? 1 : -1;

L
Linus Torvalds 已提交
5758
		dev->gflags ^= IFF_ALLMULTI;
5759
		__dev_set_allmulti(dev, inc, false);
L
Linus Torvalds 已提交
5760 5761
	}

5762 5763 5764
	return ret;
}

5765 5766
void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
			unsigned int gchanges)
5767 5768 5769
{
	unsigned int changes = dev->flags ^ old_flags;

5770
	if (gchanges)
5771
		rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
5772

5773 5774 5775 5776 5777 5778 5779 5780
	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 &&
5781 5782 5783 5784 5785 5786 5787
	    (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);
	}
5788 5789 5790 5791 5792 5793 5794 5795 5796 5797
}

/**
 *	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.
 */
5798
int dev_change_flags(struct net_device *dev, unsigned int flags)
5799
{
5800
	int ret;
5801
	unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
5802 5803 5804 5805 5806

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

5807
	changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
5808
	__dev_notify_flags(dev, old_flags, changes);
L
Linus Torvalds 已提交
5809 5810
	return ret;
}
E
Eric Dumazet 已提交
5811
EXPORT_SYMBOL(dev_change_flags);
L
Linus Torvalds 已提交
5812

5813 5814 5815 5816 5817 5818 5819 5820 5821 5822 5823
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;
}

5824 5825 5826 5827 5828 5829 5830
/**
 *	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
5831 5832
int dev_set_mtu(struct net_device *dev, int new_mtu)
{
5833
	int err, orig_mtu;
L
Linus Torvalds 已提交
5834 5835 5836 5837 5838 5839 5840 5841 5842 5843 5844

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

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

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

5845 5846 5847 5848
	err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
	err = notifier_to_errno(err);
	if (err)
		return err;
5849

5850 5851
	orig_mtu = dev->mtu;
	err = __dev_set_mtu(dev, new_mtu);
5852

5853 5854 5855 5856 5857 5858 5859 5860 5861 5862 5863
	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
5864 5865
	return err;
}
E
Eric Dumazet 已提交
5866
EXPORT_SYMBOL(dev_set_mtu);
L
Linus Torvalds 已提交
5867

5868 5869 5870 5871 5872 5873 5874 5875 5876 5877 5878
/**
 *	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);

5879 5880 5881 5882 5883 5884 5885
/**
 *	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
5886 5887
int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
{
5888
	const struct net_device_ops *ops = dev->netdev_ops;
L
Linus Torvalds 已提交
5889 5890
	int err;

5891
	if (!ops->ndo_set_mac_address)
L
Linus Torvalds 已提交
5892 5893 5894 5895 5896
		return -EOPNOTSUPP;
	if (sa->sa_family != dev->type)
		return -EINVAL;
	if (!netif_device_present(dev))
		return -ENODEV;
5897
	err = ops->ndo_set_mac_address(dev, sa);
5898 5899
	if (err)
		return err;
J
Jiri Pirko 已提交
5900
	dev->addr_assign_type = NET_ADDR_SET;
5901
	call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
5902
	add_device_randomness(dev->dev_addr, dev->addr_len);
5903
	return 0;
L
Linus Torvalds 已提交
5904
}
E
Eric Dumazet 已提交
5905
EXPORT_SYMBOL(dev_set_mac_address);
L
Linus Torvalds 已提交
5906

J
Jiri Pirko 已提交
5907 5908 5909
/**
 *	dev_change_carrier - Change device carrier
 *	@dev: device
5910
 *	@new_carrier: new value
J
Jiri Pirko 已提交
5911 5912 5913 5914 5915 5916 5917 5918 5919 5920 5921 5922 5923 5924 5925
 *
 *	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);

5926 5927 5928 5929 5930 5931 5932 5933
/**
 *	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,
5934
			 struct netdev_phys_item_id *ppid)
5935 5936 5937 5938 5939 5940 5941 5942 5943
{
	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);

5944 5945 5946 5947 5948 5949 5950 5951 5952 5953 5954 5955 5956 5957 5958 5959 5960 5961
/**
 *	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
5962 5963
/**
 *	dev_new_index	-	allocate an ifindex
5964
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
5965 5966 5967 5968 5969
 *
 *	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.
 */
5970
static int dev_new_index(struct net *net)
L
Linus Torvalds 已提交
5971
{
5972
	int ifindex = net->ifindex;
L
Linus Torvalds 已提交
5973 5974 5975
	for (;;) {
		if (++ifindex <= 0)
			ifindex = 1;
5976
		if (!__dev_get_by_index(net, ifindex))
5977
			return net->ifindex = ifindex;
L
Linus Torvalds 已提交
5978 5979 5980 5981
	}
}

/* Delayed registration/unregisteration */
5982
static LIST_HEAD(net_todo_list);
5983
DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
L
Linus Torvalds 已提交
5984

5985
static void net_set_todo(struct net_device *dev)
L
Linus Torvalds 已提交
5986 5987
{
	list_add_tail(&dev->todo_list, &net_todo_list);
5988
	dev_net(dev)->dev_unreg_count++;
L
Linus Torvalds 已提交
5989 5990
}

5991
static void rollback_registered_many(struct list_head *head)
5992
{
5993
	struct net_device *dev, *tmp;
5994
	LIST_HEAD(close_head);
5995

5996 5997 5998
	BUG_ON(dev_boot_phase);
	ASSERT_RTNL();

5999
	list_for_each_entry_safe(dev, tmp, head, unreg_list) {
6000
		/* Some devices call without registering
6001 6002
		 * for initialization unwind. Remove those
		 * devices and proceed with the remaining.
6003 6004
		 */
		if (dev->reg_state == NETREG_UNINITIALIZED) {
6005 6006
			pr_debug("unregister_netdevice: device %s/%p never was registered\n",
				 dev->name, dev);
6007

6008
			WARN_ON(1);
6009 6010
			list_del(&dev->unreg_list);
			continue;
6011
		}
6012
		dev->dismantle = true;
6013
		BUG_ON(dev->reg_state != NETREG_REGISTERED);
6014
	}
6015

6016
	/* If device is running, close it first. */
6017 6018
	list_for_each_entry(dev, head, unreg_list)
		list_add_tail(&dev->close_list, &close_head);
6019
	dev_close_many(&close_head, true);
6020

6021
	list_for_each_entry(dev, head, unreg_list) {
6022 6023
		/* And unlink it from device chain. */
		unlist_netdevice(dev);
6024

6025 6026
		dev->reg_state = NETREG_UNREGISTERING;
	}
6027 6028 6029

	synchronize_net();

6030
	list_for_each_entry(dev, head, unreg_list) {
6031 6032
		struct sk_buff *skb = NULL;

6033 6034
		/* Shutdown queueing discipline. */
		dev_shutdown(dev);
6035 6036


6037 6038 6039 6040
		/* Notify protocols, that we are about to destroy
		   this device. They should clean all the things.
		*/
		call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6041

6042 6043 6044 6045 6046
		if (!dev->rtnl_link_ops ||
		    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
			skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U,
						     GFP_KERNEL);

6047 6048 6049
		/*
		 *	Flush the unicast and multicast chains
		 */
6050
		dev_uc_flush(dev);
6051
		dev_mc_flush(dev);
6052

6053 6054
		if (dev->netdev_ops->ndo_uninit)
			dev->netdev_ops->ndo_uninit(dev);
6055

6056 6057
		if (skb)
			rtmsg_ifinfo_send(skb, dev, GFP_KERNEL);
6058

J
Jiri Pirko 已提交
6059 6060
		/* Notifier chain MUST detach us all upper devices. */
		WARN_ON(netdev_has_any_upper_dev(dev));
6061

6062 6063
		/* Remove entries from kobject tree */
		netdev_unregister_kobject(dev);
6064 6065 6066 6067
#ifdef CONFIG_XPS
		/* Remove XPS queueing entries */
		netif_reset_xps_queues_gt(dev, 0);
#endif
6068
	}
6069

6070
	synchronize_net();
6071

6072
	list_for_each_entry(dev, head, unreg_list)
6073 6074 6075 6076 6077 6078 6079 6080 6081
		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
6082
	list_del(&single);
6083 6084
}

6085 6086
static netdev_features_t netdev_fix_features(struct net_device *dev,
	netdev_features_t features)
6087
{
6088 6089 6090
	/* Fix illegal checksum combinations */
	if ((features & NETIF_F_HW_CSUM) &&
	    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
6091
		netdev_warn(dev, "mixed HW and IP checksum settings.\n");
6092 6093 6094
		features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
	}

6095
	/* TSO requires that SG is present as well. */
6096
	if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
6097
		netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
6098
		features &= ~NETIF_F_ALL_TSO;
6099 6100
	}

6101 6102 6103 6104 6105 6106 6107 6108 6109 6110 6111 6112 6113
	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;
	}

6114 6115 6116 6117
	/* TSO ECN requires that TSO is present as well. */
	if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
		features &= ~NETIF_F_TSO_ECN;

6118 6119
	/* Software GSO depends on SG. */
	if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
6120
		netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
6121 6122 6123
		features &= ~NETIF_F_GSO;
	}

6124
	/* UFO needs SG and checksumming */
6125
	if (features & NETIF_F_UFO) {
6126 6127 6128 6129
		/* 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))) {
6130
			netdev_dbg(dev,
6131
				"Dropping NETIF_F_UFO since no checksum offload features.\n");
6132 6133 6134 6135
			features &= ~NETIF_F_UFO;
		}

		if (!(features & NETIF_F_SG)) {
6136
			netdev_dbg(dev,
6137
				"Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
6138 6139 6140 6141
			features &= ~NETIF_F_UFO;
		}
	}

J
Jiri Pirko 已提交
6142 6143 6144 6145 6146 6147 6148
#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;

6149 6150 6151
	return features;
}

6152
int __netdev_update_features(struct net_device *dev)
6153
{
6154
	netdev_features_t features;
6155 6156
	int err = 0;

6157 6158
	ASSERT_RTNL();

6159 6160 6161 6162 6163 6164 6165 6166 6167
	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)
6168
		return 0;
6169

6170 6171
	netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
		&dev->features, &features);
6172 6173 6174 6175

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

6176
	if (unlikely(err < 0)) {
6177
		netdev_err(dev,
6178 6179
			"set_features() failed (%d); wanted %pNF, left %pNF\n",
			err, &features, &dev->features);
6180 6181 6182 6183 6184 6185 6186 6187 6188
		return -1;
	}

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

	return 1;
}

6189 6190 6191 6192 6193 6194 6195 6196
/**
 *	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.
 */
6197 6198 6199 6200
void netdev_update_features(struct net_device *dev)
{
	if (__netdev_update_features(dev))
		netdev_features_change(dev);
6201 6202 6203
}
EXPORT_SYMBOL(netdev_update_features);

6204 6205 6206 6207 6208 6209 6210 6211 6212 6213 6214 6215 6216 6217 6218 6219 6220
/**
 *	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);

6221 6222 6223 6224 6225 6226 6227 6228 6229 6230 6231 6232 6233 6234 6235 6236 6237 6238 6239 6240 6241 6242 6243 6244 6245 6246 6247
/**
 *	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);

6248
#ifdef CONFIG_SYSFS
6249 6250 6251
static int netif_alloc_rx_queues(struct net_device *dev)
{
	unsigned int i, count = dev->num_rx_queues;
T
Tom Herbert 已提交
6252
	struct netdev_rx_queue *rx;
6253
	size_t sz = count * sizeof(*rx);
6254

T
Tom Herbert 已提交
6255
	BUG_ON(count < 1);
6256

6257 6258 6259 6260 6261 6262
	rx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!rx) {
		rx = vzalloc(sz);
		if (!rx)
			return -ENOMEM;
	}
T
Tom Herbert 已提交
6263 6264 6265
	dev->_rx = rx;

	for (i = 0; i < count; i++)
T
Tom Herbert 已提交
6266
		rx[i].dev = dev;
6267 6268
	return 0;
}
T
Tom Herbert 已提交
6269
#endif
6270

C
Changli Gao 已提交
6271 6272 6273 6274 6275 6276 6277
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;
6278
	netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
C
Changli Gao 已提交
6279
	queue->dev = dev;
T
Tom Herbert 已提交
6280 6281 6282
#ifdef CONFIG_BQL
	dql_init(&queue->dql, HZ);
#endif
C
Changli Gao 已提交
6283 6284
}

6285 6286
static void netif_free_tx_queues(struct net_device *dev)
{
W
WANG Cong 已提交
6287
	kvfree(dev->_tx);
6288 6289
}

6290 6291 6292 6293
static int netif_alloc_netdev_queues(struct net_device *dev)
{
	unsigned int count = dev->num_tx_queues;
	struct netdev_queue *tx;
6294
	size_t sz = count * sizeof(*tx);
6295

6296
	BUG_ON(count < 1 || count > 0xffff);
6297

6298 6299 6300 6301 6302 6303
	tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!tx) {
		tx = vzalloc(sz);
		if (!tx)
			return -ENOMEM;
	}
6304
	dev->_tx = tx;
T
Tom Herbert 已提交
6305

6306 6307
	netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
	spin_lock_init(&dev->tx_global_lock);
C
Changli Gao 已提交
6308 6309

	return 0;
6310 6311
}

L
Linus Torvalds 已提交
6312 6313 6314 6315 6316 6317 6318 6319 6320 6321 6322 6323 6324 6325 6326 6327 6328 6329 6330 6331
/**
 *	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;
6332
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
6333 6334 6335 6336

	BUG_ON(dev_boot_phase);
	ASSERT_RTNL();

6337 6338
	might_sleep();

L
Linus Torvalds 已提交
6339 6340
	/* When net_device's are persistent, this will be fatal. */
	BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
6341
	BUG_ON(!net);
L
Linus Torvalds 已提交
6342

6343
	spin_lock_init(&dev->addr_list_lock);
6344
	netdev_set_addr_lockdep_class(dev);
L
Linus Torvalds 已提交
6345

6346
	ret = dev_get_valid_name(net, dev, dev->name);
6347 6348 6349
	if (ret < 0)
		goto out;

L
Linus Torvalds 已提交
6350
	/* Init, if this function is available */
6351 6352
	if (dev->netdev_ops->ndo_init) {
		ret = dev->netdev_ops->ndo_init(dev);
L
Linus Torvalds 已提交
6353 6354 6355
		if (ret) {
			if (ret > 0)
				ret = -EIO;
6356
			goto out;
L
Linus Torvalds 已提交
6357 6358
		}
	}
6359

6360 6361
	if (((dev->hw_features | dev->features) &
	     NETIF_F_HW_VLAN_CTAG_FILTER) &&
6362 6363 6364 6365 6366 6367 6368
	    (!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;
	}

6369 6370 6371 6372 6373 6374
	ret = -EBUSY;
	if (!dev->ifindex)
		dev->ifindex = dev_new_index(net);
	else if (__dev_get_by_index(net, dev->ifindex))
		goto err_uninit;

6375 6376 6377 6378
	/* Transfer changeable features to wanted_features and enable
	 * software offloads (GSO and GRO).
	 */
	dev->hw_features |= NETIF_F_SOFT_FEATURES;
6379 6380
	dev->features |= NETIF_F_SOFT_FEATURES;
	dev->wanted_features = dev->features & dev->hw_features;
L
Linus Torvalds 已提交
6381

6382 6383
	if (!(dev->flags & IFF_LOOPBACK)) {
		dev->hw_features |= NETIF_F_NOCACHE_COPY;
6384 6385
	}

6386
	/* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
6387
	 */
6388
	dev->vlan_features |= NETIF_F_HIGHDMA;
6389

6390 6391 6392 6393
	/* Make NETIF_F_SG inheritable to tunnel devices.
	 */
	dev->hw_enc_features |= NETIF_F_SG;

S
Simon Horman 已提交
6394 6395 6396 6397
	/* Make NETIF_F_SG inheritable to MPLS.
	 */
	dev->mpls_features |= NETIF_F_SG;

6398 6399 6400 6401 6402
	ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
	ret = notifier_to_errno(ret);
	if (ret)
		goto err_uninit;

6403
	ret = netdev_register_kobject(dev);
6404
	if (ret)
6405
		goto err_uninit;
6406 6407
	dev->reg_state = NETREG_REGISTERED;

6408
	__netdev_update_features(dev);
6409

L
Linus Torvalds 已提交
6410 6411 6412 6413 6414 6415 6416
	/*
	 *	Default initial state at registry is that the
	 *	device is present.
	 */

	set_bit(__LINK_STATE_PRESENT, &dev->state);

6417 6418
	linkwatch_init_dev(dev);

L
Linus Torvalds 已提交
6419 6420
	dev_init_scheduler(dev);
	dev_hold(dev);
6421
	list_netdevice(dev);
6422
	add_device_randomness(dev->dev_addr, dev->addr_len);
L
Linus Torvalds 已提交
6423

6424 6425 6426 6427 6428 6429 6430
	/* 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
6431
	/* Notify protocols, that a new device appeared. */
6432
	ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
6433
	ret = notifier_to_errno(ret);
6434 6435 6436 6437
	if (ret) {
		rollback_registered(dev);
		dev->reg_state = NETREG_UNREGISTERED;
	}
6438 6439 6440 6441
	/*
	 *	Prevent userspace races by waiting until the network
	 *	device is fully setup before sending notifications.
	 */
6442 6443
	if (!dev->rtnl_link_ops ||
	    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
6444
		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
L
Linus Torvalds 已提交
6445 6446 6447

out:
	return ret;
6448 6449

err_uninit:
6450 6451
	if (dev->netdev_ops->ndo_uninit)
		dev->netdev_ops->ndo_uninit(dev);
6452
	goto out;
L
Linus Torvalds 已提交
6453
}
E
Eric Dumazet 已提交
6454
EXPORT_SYMBOL(register_netdevice);
L
Linus Torvalds 已提交
6455

6456 6457 6458 6459 6460 6461 6462 6463 6464 6465 6466 6467 6468 6469 6470 6471 6472 6473 6474 6475 6476 6477 6478 6479 6480 6481 6482 6483 6484 6485 6486
/**
 *	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
6487 6488 6489 6490 6491
	/* Note : We dont allocate pcpu_refcnt for dummy devices,
	 * because users of this 'device' dont need to change
	 * its refcount.
	 */

6492 6493 6494 6495 6496
	return 0;
}
EXPORT_SYMBOL_GPL(init_dummy_netdev);


L
Linus Torvalds 已提交
6497 6498 6499 6500 6501 6502 6503 6504 6505
/**
 *	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.
 *
6506
 *	This is a wrapper around register_netdevice that takes the rtnl semaphore
L
Linus Torvalds 已提交
6507 6508 6509 6510 6511 6512 6513 6514 6515 6516 6517 6518 6519 6520
 *	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
6521 6522 6523 6524 6525 6526 6527 6528 6529 6530
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);

6531
/**
L
Linus Torvalds 已提交
6532
 * netdev_wait_allrefs - wait until all references are gone.
6533
 * @dev: target net_device
L
Linus Torvalds 已提交
6534 6535 6536 6537 6538 6539 6540
 *
 * 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
6541
 * call dev_put.
L
Linus Torvalds 已提交
6542 6543 6544 6545
 */
static void netdev_wait_allrefs(struct net_device *dev)
{
	unsigned long rebroadcast_time, warning_time;
E
Eric Dumazet 已提交
6546
	int refcnt;
L
Linus Torvalds 已提交
6547

6548 6549
	linkwatch_forget_dev(dev);

L
Linus Torvalds 已提交
6550
	rebroadcast_time = warning_time = jiffies;
E
Eric Dumazet 已提交
6551 6552 6553
	refcnt = netdev_refcnt_read(dev);

	while (refcnt != 0) {
L
Linus Torvalds 已提交
6554
		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
6555
			rtnl_lock();
L
Linus Torvalds 已提交
6556 6557

			/* Rebroadcast unregister notification */
6558
			call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
L
Linus Torvalds 已提交
6559

6560
			__rtnl_unlock();
6561
			rcu_barrier();
6562 6563
			rtnl_lock();

6564
			call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
L
Linus Torvalds 已提交
6565 6566 6567 6568 6569 6570 6571 6572 6573 6574 6575
			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();
			}

6576
			__rtnl_unlock();
L
Linus Torvalds 已提交
6577 6578 6579 6580 6581 6582

			rebroadcast_time = jiffies;
		}

		msleep(250);

E
Eric Dumazet 已提交
6583 6584
		refcnt = netdev_refcnt_read(dev);

L
Linus Torvalds 已提交
6585
		if (time_after(jiffies, warning_time + 10 * HZ)) {
6586 6587
			pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
				 dev->name, refcnt);
L
Linus Torvalds 已提交
6588 6589 6590 6591 6592 6593 6594 6595 6596 6597 6598 6599 6600 6601 6602 6603 6604 6605 6606
			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
6607
 * We are invoked by rtnl_unlock().
L
Linus Torvalds 已提交
6608
 * This allows us to deal with problems:
6609
 * 1) We can delete sysfs objects which invoke hotplug
L
Linus Torvalds 已提交
6610 6611 6612
 *    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
6613 6614 6615
 *
 * 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
6616 6617 6618
 */
void netdev_run_todo(void)
{
6619
	struct list_head list;
L
Linus Torvalds 已提交
6620 6621

	/* Snapshot list, allow later requests */
6622
	list_replace_init(&net_todo_list, &list);
H
Herbert Xu 已提交
6623 6624

	__rtnl_unlock();
6625

6626 6627

	/* Wait for rcu callbacks to finish before next phase */
6628 6629 6630
	if (!list_empty(&list))
		rcu_barrier();

L
Linus Torvalds 已提交
6631 6632
	while (!list_empty(&list)) {
		struct net_device *dev
6633
			= list_first_entry(&list, struct net_device, todo_list);
L
Linus Torvalds 已提交
6634 6635
		list_del(&dev->todo_list);

6636
		rtnl_lock();
6637
		call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
6638
		__rtnl_unlock();
6639

6640
		if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
6641
			pr_err("network todo '%s' but state %d\n",
6642 6643 6644 6645
			       dev->name, dev->reg_state);
			dump_stack();
			continue;
		}
L
Linus Torvalds 已提交
6646

6647
		dev->reg_state = NETREG_UNREGISTERED;
L
Linus Torvalds 已提交
6648

6649
		on_each_cpu(flush_backlog, dev, 1);
6650

6651
		netdev_wait_allrefs(dev);
L
Linus Torvalds 已提交
6652

6653
		/* paranoia */
E
Eric Dumazet 已提交
6654
		BUG_ON(netdev_refcnt_read(dev));
6655 6656
		BUG_ON(!list_empty(&dev->ptype_all));
		BUG_ON(!list_empty(&dev->ptype_specific));
6657 6658
		WARN_ON(rcu_access_pointer(dev->ip_ptr));
		WARN_ON(rcu_access_pointer(dev->ip6_ptr));
6659
		WARN_ON(dev->dn_ptr);
L
Linus Torvalds 已提交
6660

6661 6662
		if (dev->destructor)
			dev->destructor(dev);
6663

6664 6665 6666 6667 6668 6669
		/* Report a network device has been unregistered */
		rtnl_lock();
		dev_net(dev)->dev_unreg_count--;
		__rtnl_unlock();
		wake_up(&netdev_unregistering_wq);

6670 6671
		/* Free network device */
		kobject_put(&dev->dev.kobj);
L
Linus Torvalds 已提交
6672 6673 6674
	}
}

6675 6676 6677
/* Convert net_device_stats to rtnl_link_stats64.  They have the same
 * fields in the same order, with only the type differing.
 */
6678 6679
void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
			     const struct net_device_stats *netdev_stats)
6680 6681
{
#if BITS_PER_LONG == 64
6682 6683
	BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
	memcpy(stats64, netdev_stats, sizeof(*stats64));
6684 6685 6686 6687 6688 6689 6690 6691 6692 6693 6694
#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
}
6695
EXPORT_SYMBOL(netdev_stats_to_stats64);
6696

6697 6698 6699
/**
 *	dev_get_stats	- get network device statistics
 *	@dev: device to get statistics from
6700
 *	@storage: place to store stats
6701
 *
6702 6703 6704 6705
 *	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.
6706
 */
6707 6708
struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
					struct rtnl_link_stats64 *storage)
6709
{
6710 6711
	const struct net_device_ops *ops = dev->netdev_ops;

6712 6713
	if (ops->ndo_get_stats64) {
		memset(storage, 0, sizeof(*storage));
6714 6715
		ops->ndo_get_stats64(dev, storage);
	} else if (ops->ndo_get_stats) {
6716
		netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
6717 6718
	} else {
		netdev_stats_to_stats64(storage, &dev->stats);
6719
	}
6720
	storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
6721
	storage->tx_dropped += atomic_long_read(&dev->tx_dropped);
6722
	return storage;
R
Rusty Russell 已提交
6723
}
6724
EXPORT_SYMBOL(dev_get_stats);
R
Rusty Russell 已提交
6725

6726
struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
6727
{
6728
	struct netdev_queue *queue = dev_ingress_queue(dev);
6729

6730 6731 6732 6733 6734 6735 6736
#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
6737
	RCU_INIT_POINTER(queue->qdisc, &noop_qdisc);
6738 6739 6740 6741
	queue->qdisc_sleeping = &noop_qdisc;
	rcu_assign_pointer(dev->ingress_queue, queue);
#endif
	return queue;
6742 6743
}

6744 6745
static const struct ethtool_ops default_ethtool_ops;

6746 6747 6748 6749 6750 6751 6752 6753
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);

6754 6755 6756 6757
void netdev_freemem(struct net_device *dev)
{
	char *addr = (char *)dev - dev->padded;

W
WANG Cong 已提交
6758
	kvfree(addr);
6759 6760
}

L
Linus Torvalds 已提交
6761
/**
T
Tom Herbert 已提交
6762
 *	alloc_netdev_mqs - allocate network device
6763 6764 6765 6766 6767 6768
 *	@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
6769 6770
 *
 *	Allocates a struct net_device with private data area for driver use
L
Li Zhong 已提交
6771
 *	and performs basic initialization.  Also allocates subqueue structs
T
Tom Herbert 已提交
6772
 *	for each queue on the device.
L
Linus Torvalds 已提交
6773
 */
T
Tom Herbert 已提交
6774
struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
6775
		unsigned char name_assign_type,
T
Tom Herbert 已提交
6776 6777
		void (*setup)(struct net_device *),
		unsigned int txqs, unsigned int rxqs)
L
Linus Torvalds 已提交
6778 6779
{
	struct net_device *dev;
6780
	size_t alloc_size;
6781
	struct net_device *p;
L
Linus Torvalds 已提交
6782

6783 6784
	BUG_ON(strlen(name) >= sizeof(dev->name));

T
Tom Herbert 已提交
6785
	if (txqs < 1) {
6786
		pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
6787 6788 6789
		return NULL;
	}

6790
#ifdef CONFIG_SYSFS
T
Tom Herbert 已提交
6791
	if (rxqs < 1) {
6792
		pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
T
Tom Herbert 已提交
6793 6794 6795 6796
		return NULL;
	}
#endif

6797
	alloc_size = sizeof(struct net_device);
6798 6799
	if (sizeof_priv) {
		/* ensure 32-byte alignment of private area */
6800
		alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
6801 6802 6803
		alloc_size += sizeof_priv;
	}
	/* ensure 32-byte alignment of whole construct */
6804
	alloc_size += NETDEV_ALIGN - 1;
L
Linus Torvalds 已提交
6805

6806 6807 6808
	p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!p)
		p = vzalloc(alloc_size);
6809
	if (!p)
L
Linus Torvalds 已提交
6810 6811
		return NULL;

6812
	dev = PTR_ALIGN(p, NETDEV_ALIGN);
L
Linus Torvalds 已提交
6813
	dev->padded = (char *)dev - (char *)p;
6814

E
Eric Dumazet 已提交
6815 6816
	dev->pcpu_refcnt = alloc_percpu(int);
	if (!dev->pcpu_refcnt)
6817
		goto free_dev;
6818 6819

	if (dev_addr_init(dev))
E
Eric Dumazet 已提交
6820
		goto free_pcpu;
6821

6822
	dev_mc_init(dev);
6823
	dev_uc_init(dev);
J
Jiri Pirko 已提交
6824

6825
	dev_net_set(dev, &init_net);
L
Linus Torvalds 已提交
6826

6827
	dev->gso_max_size = GSO_MAX_SIZE;
6828
	dev->gso_max_segs = GSO_MAX_SEGS;
6829
	dev->gso_min_segs = 0;
6830 6831 6832

	INIT_LIST_HEAD(&dev->napi_list);
	INIT_LIST_HEAD(&dev->unreg_list);
6833
	INIT_LIST_HEAD(&dev->close_list);
6834
	INIT_LIST_HEAD(&dev->link_watch_list);
6835 6836 6837 6838
	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);
6839 6840
	INIT_LIST_HEAD(&dev->ptype_all);
	INIT_LIST_HEAD(&dev->ptype_specific);
6841
	dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM;
6842 6843
	setup(dev);

T
Tom Herbert 已提交
6844 6845
	dev->num_tx_queues = txqs;
	dev->real_num_tx_queues = txqs;
6846
	if (netif_alloc_netdev_queues(dev))
6847
		goto free_all;
6848

6849
#ifdef CONFIG_SYSFS
T
Tom Herbert 已提交
6850 6851
	dev->num_rx_queues = rxqs;
	dev->real_num_rx_queues = rxqs;
T
Tom Herbert 已提交
6852
	if (netif_alloc_rx_queues(dev))
6853
		goto free_all;
E
Eric Dumazet 已提交
6854
#endif
T
Tom Herbert 已提交
6855

L
Linus Torvalds 已提交
6856
	strcpy(dev->name, name);
6857
	dev->name_assign_type = name_assign_type;
6858
	dev->group = INIT_NETDEV_GROUP;
6859 6860
	if (!dev->ethtool_ops)
		dev->ethtool_ops = &default_ethtool_ops;
L
Linus Torvalds 已提交
6861
	return dev;
6862

6863 6864 6865 6866
free_all:
	free_netdev(dev);
	return NULL;

E
Eric Dumazet 已提交
6867 6868
free_pcpu:
	free_percpu(dev->pcpu_refcnt);
6869 6870
free_dev:
	netdev_freemem(dev);
6871
	return NULL;
L
Linus Torvalds 已提交
6872
}
T
Tom Herbert 已提交
6873
EXPORT_SYMBOL(alloc_netdev_mqs);
L
Linus Torvalds 已提交
6874 6875 6876 6877 6878

/**
 *	free_netdev - free network device
 *	@dev: device
 *
6879 6880
 *	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
6881 6882 6883 6884
 *	If this is the last reference then it will be freed.
 */
void free_netdev(struct net_device *dev)
{
6885 6886
	struct napi_struct *p, *n;

6887
	netif_free_tx_queues(dev);
6888
#ifdef CONFIG_SYSFS
6889
	kvfree(dev->_rx);
T
Tom Herbert 已提交
6890
#endif
6891

6892
	kfree(rcu_dereference_protected(dev->ingress_queue, 1));
6893

6894 6895 6896
	/* Flush device addresses */
	dev_addr_flush(dev);

6897 6898 6899
	list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
		netif_napi_del(p);

E
Eric Dumazet 已提交
6900 6901 6902
	free_percpu(dev->pcpu_refcnt);
	dev->pcpu_refcnt = NULL;

S
Stephen Hemminger 已提交
6903
	/*  Compatibility with error handling in drivers */
L
Linus Torvalds 已提交
6904
	if (dev->reg_state == NETREG_UNINITIALIZED) {
6905
		netdev_freemem(dev);
L
Linus Torvalds 已提交
6906 6907 6908 6909 6910 6911
		return;
	}

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

6912 6913
	/* will free via device release */
	put_device(&dev->dev);
L
Linus Torvalds 已提交
6914
}
E
Eric Dumazet 已提交
6915
EXPORT_SYMBOL(free_netdev);
6916

6917 6918 6919 6920 6921 6922
/**
 *	synchronize_net -  Synchronize with packet receive processing
 *
 *	Wait for packets currently being received to be done.
 *	Does not block later packets from starting.
 */
6923
void synchronize_net(void)
L
Linus Torvalds 已提交
6924 6925
{
	might_sleep();
6926 6927 6928 6929
	if (rtnl_is_locked())
		synchronize_rcu_expedited();
	else
		synchronize_rcu();
L
Linus Torvalds 已提交
6930
}
E
Eric Dumazet 已提交
6931
EXPORT_SYMBOL(synchronize_net);
L
Linus Torvalds 已提交
6932 6933

/**
6934
 *	unregister_netdevice_queue - remove device from the kernel
L
Linus Torvalds 已提交
6935
 *	@dev: device
6936
 *	@head: list
6937
 *
L
Linus Torvalds 已提交
6938
 *	This function shuts down a device interface and removes it
6939
 *	from the kernel tables.
6940
 *	If head not NULL, device is queued to be unregistered later.
L
Linus Torvalds 已提交
6941 6942 6943 6944 6945
 *
 *	Callers must hold the rtnl semaphore.  You may want
 *	unregister_netdev() instead of this.
 */

6946
void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
L
Linus Torvalds 已提交
6947
{
6948 6949
	ASSERT_RTNL();

6950
	if (head) {
6951
		list_move_tail(&dev->unreg_list, head);
6952 6953 6954 6955 6956
	} else {
		rollback_registered(dev);
		/* Finish processing unregister after unlock */
		net_set_todo(dev);
	}
L
Linus Torvalds 已提交
6957
}
6958
EXPORT_SYMBOL(unregister_netdevice_queue);
L
Linus Torvalds 已提交
6959

6960 6961 6962
/**
 *	unregister_netdevice_many - unregister many devices
 *	@head: list of devices
6963 6964 6965
 *
 *  Note: As most callers use a stack allocated list_head,
 *  we force a list_del() to make sure stack wont be corrupted later.
6966 6967 6968 6969 6970 6971 6972 6973 6974
 */
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);
6975
		list_del(head);
6976 6977
	}
}
6978
EXPORT_SYMBOL(unregister_netdevice_many);
6979

L
Linus Torvalds 已提交
6980 6981 6982 6983 6984
/**
 *	unregister_netdev - remove device from the kernel
 *	@dev: device
 *
 *	This function shuts down a device interface and removes it
6985
 *	from the kernel tables.
L
Linus Torvalds 已提交
6986 6987 6988 6989 6990 6991 6992 6993 6994 6995 6996 6997 6998
 *
 *	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);

6999 7000 7001 7002 7003 7004 7005 7006 7007 7008 7009 7010 7011 7012 7013 7014 7015 7016 7017 7018 7019 7020 7021 7022 7023 7024 7025 7026 7027 7028 7029
/**
 *	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;
7030
	if (net_eq(dev_net(dev), net))
7031 7032 7033 7034 7035 7036
		goto out;

	/* Pick the destination device name, and ensure
	 * we can use it in the destination network namespace.
	 */
	err = -EEXIST;
7037
	if (__dev_get_by_name(net, dev->name)) {
7038 7039 7040
		/* We get here if we can't use the current device name */
		if (!pat)
			goto out;
7041
		if (dev_get_valid_name(net, dev, pat) < 0)
7042 7043 7044 7045 7046 7047 7048 7049
			goto out;
	}

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

	/* If device is running close it first. */
7050
	dev_close(dev);
7051 7052 7053 7054 7055 7056 7057 7058 7059 7060 7061 7062

	/* 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.
7063 7064 7065 7066

	   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.
7067 7068
	*/
	call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
7069 7070
	rcu_barrier();
	call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
7071
	rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
7072 7073 7074 7075

	/*
	 *	Flush the unicast and multicast chains
	 */
7076
	dev_uc_flush(dev);
7077
	dev_mc_flush(dev);
7078

7079 7080
	/* Send a netdev-removed uevent to the old namespace */
	kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
7081
	netdev_adjacent_del_links(dev);
7082

7083
	/* Actually switch the network namespace */
7084
	dev_net_set(dev, net);
7085 7086

	/* If there is an ifindex conflict assign a new one */
7087
	if (__dev_get_by_index(net, dev->ifindex))
7088 7089
		dev->ifindex = dev_new_index(net);

7090 7091
	/* Send a netdev-add uevent to the new namespace */
	kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
7092
	netdev_adjacent_add_links(dev);
7093

7094
	/* Fixup kobjects */
7095
	err = device_rename(&dev->dev, dev->name);
7096
	WARN_ON(err);
7097 7098 7099 7100 7101 7102 7103

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

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

7104 7105 7106 7107
	/*
	 *	Prevent userspace races by waiting until the network
	 *	device is fully setup before sending notifications.
	 */
7108
	rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
7109

7110 7111 7112 7113 7114
	synchronize_net();
	err = 0;
out:
	return err;
}
7115
EXPORT_SYMBOL_GPL(dev_change_net_namespace);
7116

L
Linus Torvalds 已提交
7117 7118 7119 7120 7121 7122 7123 7124 7125
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;

7126
	if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
L
Linus Torvalds 已提交
7127 7128 7129 7130 7131 7132 7133 7134 7135 7136 7137 7138 7139 7140 7141 7142
		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. */
7143 7144 7145 7146 7147 7148
	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
7149 7150 7151 7152 7153 7154 7155 7156 7157 7158 7159 7160 7161 7162
	/* 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);
7163
	}
L
Linus Torvalds 已提交
7164 7165 7166 7167 7168

	raise_softirq_irqoff(NET_TX_SOFTIRQ);
	local_irq_enable();

	/* Process offline CPU's input_pkt_queue */
7169
	while ((skb = __skb_dequeue(&oldsd->process_queue))) {
7170
		netif_rx_ni(skb);
7171
		input_queue_head_incr(oldsd);
T
Tom Herbert 已提交
7172
	}
E
Eric Dumazet 已提交
7173
	while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
7174
		netif_rx_ni(skb);
7175 7176
		input_queue_head_incr(oldsd);
	}
L
Linus Torvalds 已提交
7177 7178 7179 7180 7181

	return NOTIFY_OK;
}


7182
/**
7183 7184 7185 7186
 *	netdev_increment_features - increment feature set by one
 *	@all: current feature set
 *	@one: new feature set
 *	@mask: mask feature set
7187 7188
 *
 *	Computes a new feature set after adding a device with feature set
7189 7190
 *	@one to the master device with current feature set @all.  Will not
 *	enable anything that is off in @mask. Returns the new feature set.
7191
 */
7192 7193
netdev_features_t netdev_increment_features(netdev_features_t all,
	netdev_features_t one, netdev_features_t mask)
7194
{
7195 7196 7197
	if (mask & NETIF_F_GEN_CSUM)
		mask |= NETIF_F_ALL_CSUM;
	mask |= NETIF_F_VLAN_CHALLENGED;
7198

7199 7200
	all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
	all &= one | ~NETIF_F_ALL_FOR_ALL;
7201

7202 7203 7204
	/* If one device supports hw checksumming, set for all. */
	if (all & NETIF_F_GEN_CSUM)
		all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
7205 7206 7207

	return all;
}
7208
EXPORT_SYMBOL(netdev_increment_features);
7209

7210
static struct hlist_head * __net_init netdev_create_hash(void)
7211 7212 7213 7214 7215 7216 7217 7218 7219 7220 7221 7222
{
	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;
}

7223
/* Initialize per network namespace state */
7224
static int __net_init netdev_init(struct net *net)
7225
{
7226 7227
	if (net != &init_net)
		INIT_LIST_HEAD(&net->dev_base_head);
7228

7229 7230 7231
	net->dev_name_head = netdev_create_hash();
	if (net->dev_name_head == NULL)
		goto err_name;
7232

7233 7234 7235
	net->dev_index_head = netdev_create_hash();
	if (net->dev_index_head == NULL)
		goto err_idx;
7236 7237

	return 0;
7238 7239 7240 7241 7242

err_idx:
	kfree(net->dev_name_head);
err_name:
	return -ENOMEM;
7243 7244
}

7245 7246 7247 7248 7249 7250
/**
 *	netdev_drivername - network driver for the device
 *	@dev: network device
 *
 *	Determine network driver for device.
 */
7251
const char *netdev_drivername(const struct net_device *dev)
7252
{
7253 7254
	const struct device_driver *driver;
	const struct device *parent;
7255
	const char *empty = "";
7256 7257 7258

	parent = dev->dev.parent;
	if (!parent)
7259
		return empty;
7260 7261 7262

	driver = parent->driver;
	if (driver && driver->name)
7263 7264
		return driver->name;
	return empty;
7265 7266
}

7267 7268
static void __netdev_printk(const char *level, const struct net_device *dev,
			    struct va_format *vaf)
7269
{
7270
	if (dev && dev->dev.parent) {
7271 7272 7273 7274 7275 7276 7277
		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);
7278
	} else if (dev) {
7279 7280
		printk("%s%s%s: %pV",
		       level, netdev_name(dev), netdev_reg_state(dev), vaf);
7281
	} else {
7282
		printk("%s(NULL net_device): %pV", level, vaf);
7283
	}
7284 7285
}

7286 7287
void netdev_printk(const char *level, const struct net_device *dev,
		   const char *format, ...)
7288 7289 7290 7291 7292 7293 7294 7295 7296
{
	struct va_format vaf;
	va_list args;

	va_start(args, format);

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

7297
	__netdev_printk(level, dev, &vaf);
7298

7299 7300 7301 7302 7303
	va_end(args);
}
EXPORT_SYMBOL(netdev_printk);

#define define_netdev_printk_level(func, level)			\
7304
void func(const struct net_device *dev, const char *fmt, ...)	\
7305 7306 7307 7308 7309 7310 7311 7312 7313
{								\
	struct va_format vaf;					\
	va_list args;						\
								\
	va_start(args, fmt);					\
								\
	vaf.fmt = fmt;						\
	vaf.va = &args;						\
								\
7314
	__netdev_printk(level, dev, &vaf);			\
7315
								\
7316 7317 7318 7319 7320 7321 7322 7323 7324 7325 7326 7327
	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);

7328
static void __net_exit netdev_exit(struct net *net)
7329 7330 7331 7332 7333
{
	kfree(net->dev_name_head);
	kfree(net->dev_index_head);
}

7334
static struct pernet_operations __net_initdata netdev_net_ops = {
7335 7336 7337 7338
	.init = netdev_init,
	.exit = netdev_exit,
};

7339
static void __net_exit default_device_exit(struct net *net)
7340
{
7341
	struct net_device *dev, *aux;
7342
	/*
7343
	 * Push all migratable network devices back to the
7344 7345 7346
	 * initial network namespace
	 */
	rtnl_lock();
7347
	for_each_netdev_safe(net, dev, aux) {
7348
		int err;
7349
		char fb_name[IFNAMSIZ];
7350 7351 7352 7353 7354

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

7355 7356 7357
		/* Leave virtual devices for the generic cleanup */
		if (dev->rtnl_link_ops)
			continue;
7358

L
Lucas De Marchi 已提交
7359
		/* Push remaining network devices to init_net */
7360 7361
		snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
		err = dev_change_net_namespace(dev, &init_net, fb_name);
7362
		if (err) {
7363 7364
			pr_emerg("%s: failed to move %s to init_net: %d\n",
				 __func__, dev->name, err);
7365
			BUG();
7366 7367 7368 7369 7370
		}
	}
	rtnl_unlock();
}

7371 7372 7373 7374 7375 7376 7377
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;
7378
	DEFINE_WAIT_FUNC(wait, woken_wake_function);
7379

7380
	add_wait_queue(&netdev_unregistering_wq, &wait);
7381 7382 7383 7384 7385 7386 7387 7388 7389 7390 7391 7392
	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();
7393 7394

		wait_woken(&wait, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
7395
	}
7396
	remove_wait_queue(&netdev_unregistering_wq, &wait);
7397 7398
}

7399 7400 7401
static void __net_exit default_device_exit_batch(struct list_head *net_list)
{
	/* At exit all network devices most be removed from a network
7402
	 * namespace.  Do this in the reverse order of registration.
7403 7404 7405 7406 7407 7408 7409
	 * 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);

7410 7411 7412 7413 7414 7415 7416 7417 7418 7419 7420 7421
	/* 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);
7422 7423
	list_for_each_entry(net, net_list, exit_list) {
		for_each_netdev_reverse(net, dev) {
7424
			if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink)
7425 7426 7427 7428 7429 7430 7431 7432 7433
				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();
}

7434
static struct pernet_operations __net_initdata default_device_ops = {
7435
	.exit = default_device_exit,
7436
	.exit_batch = default_device_exit_batch,
7437 7438
};

L
Linus Torvalds 已提交
7439 7440 7441 7442 7443 7444 7445 7446 7447 7448 7449 7450 7451 7452 7453 7454 7455 7456 7457 7458
/*
 *	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;

7459
	if (netdev_kobject_init())
L
Linus Torvalds 已提交
7460 7461 7462
		goto out;

	INIT_LIST_HEAD(&ptype_all);
7463
	for (i = 0; i < PTYPE_HASH_SIZE; i++)
L
Linus Torvalds 已提交
7464 7465
		INIT_LIST_HEAD(&ptype_base[i]);

7466 7467
	INIT_LIST_HEAD(&offload_base);

7468 7469
	if (register_pernet_subsys(&netdev_net_ops))
		goto out;
L
Linus Torvalds 已提交
7470 7471 7472 7473 7474

	/*
	 *	Initialise the packet receive queues.
	 */

7475
	for_each_possible_cpu(i) {
E
Eric Dumazet 已提交
7476
		struct softnet_data *sd = &per_cpu(softnet_data, i);
L
Linus Torvalds 已提交
7477

E
Eric Dumazet 已提交
7478
		skb_queue_head_init(&sd->input_pkt_queue);
7479
		skb_queue_head_init(&sd->process_queue);
E
Eric Dumazet 已提交
7480
		INIT_LIST_HEAD(&sd->poll_list);
7481
		sd->output_queue_tailp = &sd->output_queue;
E
Eric Dumazet 已提交
7482
#ifdef CONFIG_RPS
E
Eric Dumazet 已提交
7483 7484 7485
		sd->csd.func = rps_trigger_softirq;
		sd->csd.info = sd;
		sd->cpu = i;
7486
#endif
T
Tom Herbert 已提交
7487

E
Eric Dumazet 已提交
7488 7489
		sd->backlog.poll = process_backlog;
		sd->backlog.weight = weight_p;
L
Linus Torvalds 已提交
7490 7491 7492 7493
	}

	dev_boot_phase = 0;

7494 7495 7496 7497 7498 7499 7500 7501 7502 7503 7504 7505 7506 7507 7508
	/* 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;

7509 7510
	open_softirq(NET_TX_SOFTIRQ, net_tx_action);
	open_softirq(NET_RX_SOFTIRQ, net_rx_action);
L
Linus Torvalds 已提交
7511 7512 7513 7514 7515 7516 7517 7518 7519

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

subsys_initcall(net_dev_init);