dev.c 206.0 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 <linux/bpf.h>
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#include <net/net_namespace.h>
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#include <net/sock.h>
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#include <net/busy_poll.h>
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#include <linux/rtnetlink.h>
#include <linux/stat.h>
#include <net/dst.h>
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#include <net/dst_metadata.h>
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#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 <linux/netfilter_ingress.h>
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#include <linux/crash_dump.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);

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static unsigned int napi_gen_id = NR_CPUS;
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static DEFINE_READ_MOSTLY_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(net, 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)
{
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	struct packet_offload *elem;
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	spin_lock(&offload_lock);
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	list_for_each_entry(elem, &offload_base, list) {
		if (po->priority < elem->priority)
			break;
	}
	list_add_rcu(&po->list, elem->list.prev);
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	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));
567
			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] != ' ' &&
592
		    !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
	 */
627
	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

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

671 672 673 674 675 676 677 678 679 680 681 682 683
/**
 *	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);

684
	return dev->ifindex;
685 686 687
}
EXPORT_SYMBOL(dev_get_iflink);

688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713
/**
 *	dev_fill_metadata_dst - Retrieve tunnel egress information.
 *	@dev: targeted interface
 *	@skb: The packet.
 *
 *	For better visibility of tunnel traffic OVS needs to retrieve
 *	egress tunnel information for a packet. Following API allows
 *	user to get this info.
 */
int dev_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
{
	struct ip_tunnel_info *info;

	if (!dev->netdev_ops  || !dev->netdev_ops->ndo_fill_metadata_dst)
		return -EINVAL;

	info = skb_tunnel_info_unclone(skb);
	if (!info)
		return -ENOMEM;
	if (unlikely(!(info->mode & IP_TUNNEL_INFO_TX)))
		return -EINVAL;

	return dev->netdev_ops->ndo_fill_metadata_dst(dev, skb);
}
EXPORT_SYMBOL_GPL(dev_fill_metadata_dst);

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/**
 *	__dev_get_by_name	- find a device by its name
716
 *	@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.
 */

726
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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731
	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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739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755
/**
 *	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);

756
	hlist_for_each_entry_rcu(dev, head, name_hlist)
757 758 759 760 761 762 763
		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
766
 *	@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.
 */

776
struct net_device *dev_get_by_name(struct net *net, const char *name)
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{
	struct net_device *dev;

780 781
	rcu_read_lock();
	dev = dev_get_by_name_rcu(net, name);
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	if (dev)
		dev_hold(dev);
784
	rcu_read_unlock();
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	return dev;
}
E
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EXPORT_SYMBOL(dev_get_by_name);
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/**
 *	__dev_get_by_index - find a device by its ifindex
791
 *	@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.
 */

801
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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805

806
	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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814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829
/**
 *	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);

830
	hlist_for_each_entry_rcu(dev, head, index_hlist)
831 832 833 834 835 836 837
		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
841
 *	@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.
 */

850
struct net_device *dev_get_by_index(struct net *net, int ifindex)
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{
	struct net_device *dev;

854 855
	rcu_read_lock();
	dev = dev_get_by_index_rcu(net, ifindex);
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	if (dev)
		dev_hold(dev);
858
	rcu_read_unlock();
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	return dev;
}
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EXPORT_SYMBOL(dev_get_by_index);
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863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896
/**
 *	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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/**
898
 *	dev_getbyhwaddr_rcu - find a device by its hardware address
899
 *	@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.
906
 *	The returned device has not had its ref count increased
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 *	and the caller must therefore be careful about locking
 *
 */

911 912
struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
				       const char *ha)
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{
	struct net_device *dev;

916
	for_each_netdev_rcu(net, dev)
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		if (dev->type == type &&
		    !memcmp(dev->dev_addr, ha, dev->addr_len))
919 920 921
			return dev;

	return NULL;
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}
923
EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
924

925
struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
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{
	struct net_device *dev;

929
	ASSERT_RTNL();
930
	for_each_netdev(net, dev)
931
		if (dev->type == type)
932 933 934
			return dev;

	return NULL;
935 936 937
}
EXPORT_SYMBOL(__dev_getfirstbyhwtype);

938
struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
939
{
940
	struct net_device *dev, *ret = NULL;
941

942 943 944 945 946 947 948 949 950
	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);

/**
955
 *	__dev_get_by_flags - find any device with given flags
956
 *	@net: the applicable net namespace
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 *	@if_flags: IFF_* values
 *	@mask: bitmask of bits in if_flags to check
 *
 *	Search for any interface with the given flags. Returns NULL if a device
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Eric Dumazet 已提交
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 *	is not found or a pointer to the device. Must be called inside
962
 *	rtnl_lock(), and result refcount is unchanged.
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 */

965 966
struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags,
				      unsigned short mask)
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{
968
	struct net_device *dev, *ret;
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970 971
	ASSERT_RTNL();

972
	ret = NULL;
973
	for_each_netdev(net, dev) {
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		if (((dev->flags ^ if_flags) & mask) == 0) {
975
			ret = dev;
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			break;
		}
	}
979
	return ret;
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}
981
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
988 989
 *	to allow sysfs to work.  We also disallow any kind of
 *	whitespace.
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 */
991
bool dev_valid_name(const char *name)
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{
993
	if (*name == '\0')
994
		return false;
995
	if (strlen(name) >= IFNAMSIZ)
996
		return false;
997
	if (!strcmp(name, ".") || !strcmp(name, ".."))
998
		return false;
999 1000

	while (*name) {
1001
		if (*name == '/' || *name == ':' || isspace(*name))
1002
			return false;
1003 1004
		name++;
	}
1005
	return true;
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}
E
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1007
EXPORT_SYMBOL(dev_valid_name);
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/**
1010 1011
 *	__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
1013
 *	@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
S
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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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 */

1024
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
Stephen Hemminger 已提交
1029
	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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Stephen Hemminger 已提交
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		inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
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1044 1045 1046
		if (!inuse)
			return -ENOMEM;

1047
		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 */
1054
			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);
	}

1063 1064
	if (buf != name)
		snprintf(buf, IFNAMSIZ, name, i);
1065
	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;
}

1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094
/**
 *	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;

1095 1096
	BUG_ON(!dev_net(dev));
	net = dev_net(dev);
1097 1098 1099 1100 1101
	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);
1103

1104 1105 1106
static int dev_alloc_name_ns(struct net *net,
			     struct net_device *dev,
			     const char *name)
1107
{
1108 1109
	char buf[IFNAMSIZ];
	int ret;
1110

1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121
	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);
1122

1123 1124 1125
	if (!dev_valid_name(name))
		return -EINVAL;

1126
	if (strchr(name, '%'))
1127
		return dev_alloc_name_ns(net, dev, name);
1128 1129
	else if (__dev_get_by_name(net, name))
		return -EEXIST;
1130 1131
	else if (dev->name != name)
		strlcpy(dev->name, name, IFNAMSIZ);
1132 1133 1134

	return 0;
}
L
Linus Torvalds 已提交
1135 1136 1137 1138 1139 1140 1141 1142 1143

/**
 *	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.
 */
1144
int dev_change_name(struct net_device *dev, const char *newname)
L
Linus Torvalds 已提交
1145
{
1146
	unsigned char old_assign_type;
1147
	char oldname[IFNAMSIZ];
L
Linus Torvalds 已提交
1148
	int err = 0;
1149
	int ret;
1150
	struct net *net;
L
Linus Torvalds 已提交
1151 1152

	ASSERT_RTNL();
1153
	BUG_ON(!dev_net(dev));
L
Linus Torvalds 已提交
1154

1155
	net = dev_net(dev);
L
Linus Torvalds 已提交
1156 1157 1158
	if (dev->flags & IFF_UP)
		return -EBUSY;

1159
	write_seqcount_begin(&devnet_rename_seq);
1160 1161

	if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
1162
		write_seqcount_end(&devnet_rename_seq);
1163
		return 0;
1164
	}
1165

1166 1167
	memcpy(oldname, dev->name, IFNAMSIZ);

1168
	err = dev_get_valid_name(net, dev, newname);
1169
	if (err < 0) {
1170
		write_seqcount_end(&devnet_rename_seq);
1171
		return err;
1172
	}
L
Linus Torvalds 已提交
1173

1174 1175 1176
	if (oldname[0] && !strchr(oldname, '%'))
		netdev_info(dev, "renamed from %s\n", oldname);

1177 1178 1179
	old_assign_type = dev->name_assign_type;
	dev->name_assign_type = NET_NAME_RENAMED;

1180
rollback:
1181 1182 1183
	ret = device_rename(&dev->dev, dev->name);
	if (ret) {
		memcpy(dev->name, oldname, IFNAMSIZ);
1184
		dev->name_assign_type = old_assign_type;
1185
		write_seqcount_end(&devnet_rename_seq);
1186
		return ret;
1187
	}
1188

1189
	write_seqcount_end(&devnet_rename_seq);
1190

1191 1192
	netdev_adjacent_rename_links(dev, oldname);

1193
	write_lock_bh(&dev_base_lock);
1194
	hlist_del_rcu(&dev->name_hlist);
1195 1196 1197 1198 1199 1200
	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));
1201 1202
	write_unlock_bh(&dev_base_lock);

1203
	ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
1204 1205 1206
	ret = notifier_to_errno(ret);

	if (ret) {
1207 1208
		/* err >= 0 after dev_alloc_name() or stores the first errno */
		if (err >= 0) {
1209
			err = ret;
1210
			write_seqcount_begin(&devnet_rename_seq);
1211
			memcpy(dev->name, oldname, IFNAMSIZ);
1212
			memcpy(oldname, newname, IFNAMSIZ);
1213 1214
			dev->name_assign_type = old_assign_type;
			old_assign_type = NET_NAME_RENAMED;
1215
			goto rollback;
1216
		} else {
1217
			pr_err("%s: name change rollback failed: %d\n",
1218
			       dev->name, ret);
1219 1220
		}
	}
L
Linus Torvalds 已提交
1221 1222 1223 1224

	return err;
}

1225 1226 1227 1228
/**
 *	dev_set_alias - change ifalias of a device
 *	@dev: device
 *	@alias: name up to IFALIASZ
1229
 *	@len: limit of bytes to copy from info
1230 1231 1232 1233 1234
 *
 *	Set ifalias for a device,
 */
int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
{
1235 1236
	char *new_ifalias;

1237 1238 1239 1240 1241
	ASSERT_RTNL();

	if (len >= IFALIASZ)
		return -EINVAL;

1242
	if (!len) {
1243 1244
		kfree(dev->ifalias);
		dev->ifalias = NULL;
1245 1246 1247
		return 0;
	}

1248 1249
	new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
	if (!new_ifalias)
1250
		return -ENOMEM;
1251
	dev->ifalias = new_ifalias;
1252 1253 1254 1255 1256 1257

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


1258
/**
S
Stephen Hemminger 已提交
1259
 *	netdev_features_change - device changes features
1260 1261 1262 1263 1264 1265
 *	@dev: device to cause notification
 *
 *	Called to indicate a device has changed features.
 */
void netdev_features_change(struct net_device *dev)
{
1266
	call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
1267 1268 1269
}
EXPORT_SYMBOL(netdev_features_change);

L
Linus Torvalds 已提交
1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280
/**
 *	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) {
1281 1282 1283 1284 1285
		struct netdev_notifier_change_info change_info;

		change_info.flags_changed = 0;
		call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
					      &change_info.info);
1286
		rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL);
L
Linus Torvalds 已提交
1287 1288
	}
}
E
Eric Dumazet 已提交
1289
EXPORT_SYMBOL(netdev_state_change);
L
Linus Torvalds 已提交
1290

1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301
/**
 * 	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)
1302
{
1303 1304 1305
	rtnl_lock();
	call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
	rtnl_unlock();
1306
}
1307
EXPORT_SYMBOL(netdev_notify_peers);
1308

1309
static int __dev_open(struct net_device *dev)
L
Linus Torvalds 已提交
1310
{
1311
	const struct net_device_ops *ops = dev->netdev_ops;
1312
	int ret;
L
Linus Torvalds 已提交
1313

1314 1315
	ASSERT_RTNL();

L
Linus Torvalds 已提交
1316 1317 1318
	if (!netif_device_present(dev))
		return -ENODEV;

1319 1320 1321 1322
	/* 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
	 */
1323
	netpoll_poll_disable(dev);
1324

1325 1326 1327 1328 1329
	ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
	ret = notifier_to_errno(ret);
	if (ret)
		return ret;

L
Linus Torvalds 已提交
1330
	set_bit(__LINK_STATE_START, &dev->state);
1331

1332 1333
	if (ops->ndo_validate_addr)
		ret = ops->ndo_validate_addr(dev);
1334

1335 1336
	if (!ret && ops->ndo_open)
		ret = ops->ndo_open(dev);
L
Linus Torvalds 已提交
1337

1338
	netpoll_poll_enable(dev);
1339

1340 1341 1342
	if (ret)
		clear_bit(__LINK_STATE_START, &dev->state);
	else {
L
Linus Torvalds 已提交
1343
		dev->flags |= IFF_UP;
1344
		dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
1345
		dev_activate(dev);
1346
		add_device_randomness(dev->dev_addr, dev->addr_len);
L
Linus Torvalds 已提交
1347
	}
1348

L
Linus Torvalds 已提交
1349 1350 1351 1352
	return ret;
}

/**
1353 1354
 *	dev_open	- prepare an interface for use.
 *	@dev:	device to open
L
Linus Torvalds 已提交
1355
 *
1356 1357 1358 1359 1360 1361 1362
 *	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
1363
 */
1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374
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;

1375
	rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1376 1377 1378 1379 1380 1381
	call_netdevice_notifiers(NETDEV_UP, dev);

	return ret;
}
EXPORT_SYMBOL(dev_open);

1382
static int __dev_close_many(struct list_head *head)
L
Linus Torvalds 已提交
1383
{
1384
	struct net_device *dev;
1385

1386
	ASSERT_RTNL();
1387 1388
	might_sleep();

1389
	list_for_each_entry(dev, head, close_list) {
1390
		/* Temporarily disable netpoll until the interface is down */
1391
		netpoll_poll_disable(dev);
1392

1393
		call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
L
Linus Torvalds 已提交
1394

1395
		clear_bit(__LINK_STATE_START, &dev->state);
L
Linus Torvalds 已提交
1396

1397 1398 1399 1400 1401 1402
		/* 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.
		 */
1403
		smp_mb__after_atomic(); /* Commit netif_running(). */
1404
	}
L
Linus Torvalds 已提交
1405

1406
	dev_deactivate_many(head);
1407

1408
	list_for_each_entry(dev, head, close_list) {
1409
		const struct net_device_ops *ops = dev->netdev_ops;
L
Linus Torvalds 已提交
1410

1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421
		/*
		 *	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;
1422
		netpoll_poll_enable(dev);
1423 1424 1425 1426 1427 1428 1429
	}

	return 0;
}

static int __dev_close(struct net_device *dev)
{
1430
	int retval;
1431 1432
	LIST_HEAD(single);

1433
	list_add(&dev->close_list, &single);
1434 1435
	retval = __dev_close_many(&single);
	list_del(&single);
1436

1437
	return retval;
1438 1439
}

1440
int dev_close_many(struct list_head *head, bool unlink)
1441 1442
{
	struct net_device *dev, *tmp;
L
Linus Torvalds 已提交
1443

1444 1445
	/* Remove the devices that don't need to be closed */
	list_for_each_entry_safe(dev, tmp, head, close_list)
1446
		if (!(dev->flags & IFF_UP))
1447
			list_del_init(&dev->close_list);
1448 1449

	__dev_close_many(head);
L
Linus Torvalds 已提交
1450

1451
	list_for_each_entry_safe(dev, tmp, head, close_list) {
1452
		rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
1453
		call_netdevice_notifiers(NETDEV_DOWN, dev);
1454 1455
		if (unlink)
			list_del_init(&dev->close_list);
1456
	}
1457 1458 1459

	return 0;
}
1460
EXPORT_SYMBOL(dev_close_many);
1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472

/**
 *	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)
{
1473 1474
	if (dev->flags & IFF_UP) {
		LIST_HEAD(single);
L
Linus Torvalds 已提交
1475

1476
		list_add(&dev->close_list, &single);
1477
		dev_close_many(&single, true);
1478 1479
		list_del(&single);
	}
1480
	return 0;
L
Linus Torvalds 已提交
1481
}
E
Eric Dumazet 已提交
1482
EXPORT_SYMBOL(dev_close);
L
Linus Torvalds 已提交
1483 1484


1485 1486 1487 1488 1489 1490 1491 1492 1493 1494
/**
 *	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)
{
1495 1496
	struct net_device *lower_dev;
	struct list_head *iter;
1497

M
Michał Mirosław 已提交
1498 1499
	dev->wanted_features &= ~NETIF_F_LRO;
	netdev_update_features(dev);
1500

1501 1502
	if (unlikely(dev->features & NETIF_F_LRO))
		netdev_WARN(dev, "failed to disable LRO!\n");
1503 1504 1505

	netdev_for_each_lower_dev(dev, lower_dev, iter)
		dev_disable_lro(lower_dev);
1506 1507 1508
}
EXPORT_SYMBOL(dev_disable_lro);

1509 1510 1511 1512 1513 1514 1515 1516
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);
}
1517

1518 1519
static int dev_boot_phase = 1;

L
Linus Torvalds 已提交
1520 1521 1522 1523 1524 1525 1526 1527 1528 1529
/**
 *	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
1530
 *	to the new notifier to allow device to have a race free
L
Linus Torvalds 已提交
1531 1532 1533 1534 1535 1536
 *	view of the network device list.
 */

int register_netdevice_notifier(struct notifier_block *nb)
{
	struct net_device *dev;
1537
	struct net_device *last;
1538
	struct net *net;
L
Linus Torvalds 已提交
1539 1540 1541
	int err;

	rtnl_lock();
1542
	err = raw_notifier_chain_register(&netdev_chain, nb);
1543 1544
	if (err)
		goto unlock;
1545 1546 1547 1548
	if (dev_boot_phase)
		goto unlock;
	for_each_net(net) {
		for_each_netdev(net, dev) {
1549
			err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
1550 1551 1552 1553 1554 1555
			err = notifier_to_errno(err);
			if (err)
				goto rollback;

			if (!(dev->flags & IFF_UP))
				continue;
L
Linus Torvalds 已提交
1556

1557
			call_netdevice_notifier(nb, NETDEV_UP, dev);
1558
		}
L
Linus Torvalds 已提交
1559
	}
1560 1561

unlock:
L
Linus Torvalds 已提交
1562 1563
	rtnl_unlock();
	return err;
1564 1565 1566

rollback:
	last = dev;
1567 1568 1569
	for_each_net(net) {
		for_each_netdev(net, dev) {
			if (dev == last)
1570
				goto outroll;
1571

1572
			if (dev->flags & IFF_UP) {
1573 1574 1575
				call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
							dev);
				call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1576
			}
1577
			call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1578 1579
		}
	}
1580

1581
outroll:
1582
	raw_notifier_chain_unregister(&netdev_chain, nb);
1583
	goto unlock;
L
Linus Torvalds 已提交
1584
}
E
Eric Dumazet 已提交
1585
EXPORT_SYMBOL(register_netdevice_notifier);
L
Linus Torvalds 已提交
1586 1587 1588 1589 1590 1591 1592 1593 1594

/**
 *	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.
1595 1596 1597 1598
 *
 * 	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
1599 1600 1601 1602
 */

int unregister_netdevice_notifier(struct notifier_block *nb)
{
1603 1604
	struct net_device *dev;
	struct net *net;
1605 1606 1607
	int err;

	rtnl_lock();
1608
	err = raw_notifier_chain_unregister(&netdev_chain, nb);
1609 1610 1611 1612 1613 1614
	if (err)
		goto unlock;

	for_each_net(net) {
		for_each_netdev(net, dev) {
			if (dev->flags & IFF_UP) {
1615 1616 1617
				call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
							dev);
				call_netdevice_notifier(nb, NETDEV_DOWN, dev);
1618
			}
1619
			call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
1620 1621 1622
		}
	}
unlock:
1623 1624
	rtnl_unlock();
	return err;
L
Linus Torvalds 已提交
1625
}
E
Eric Dumazet 已提交
1626
EXPORT_SYMBOL(unregister_netdevice_notifier);
L
Linus Torvalds 已提交
1627

1628 1629 1630 1631 1632 1633 1634 1635 1636 1637
/**
 *	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
1638 1639 1640
static int call_netdevice_notifiers_info(unsigned long val,
					 struct net_device *dev,
					 struct netdev_notifier_info *info)
1641 1642 1643 1644 1645 1646
{
	ASSERT_RTNL();
	netdev_notifier_info_init(info, dev);
	return raw_notifier_call_chain(&netdev_chain, val, info);
}

L
Linus Torvalds 已提交
1647 1648 1649
/**
 *	call_netdevice_notifiers - call all network notifier blocks
 *      @val: value passed unmodified to notifier function
1650
 *      @dev: net_device pointer passed unmodified to notifier function
L
Linus Torvalds 已提交
1651 1652
 *
 *	Call all network notifier blocks.  Parameters and return value
1653
 *	are as for raw_notifier_call_chain().
L
Linus Torvalds 已提交
1654 1655
 */

1656
int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
L
Linus Torvalds 已提交
1657
{
1658 1659 1660
	struct netdev_notifier_info info;

	return call_netdevice_notifiers_info(val, dev, &info);
L
Linus Torvalds 已提交
1661
}
1662
EXPORT_SYMBOL(call_netdevice_notifiers);
L
Linus Torvalds 已提交
1663

1664
#ifdef CONFIG_NET_INGRESS
1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679
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

D
Daniel Borkmann 已提交
1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695
#ifdef CONFIG_NET_EGRESS
static struct static_key egress_needed __read_mostly;

void net_inc_egress_queue(void)
{
	static_key_slow_inc(&egress_needed);
}
EXPORT_SYMBOL_GPL(net_inc_egress_queue);

void net_dec_egress_queue(void)
{
	static_key_slow_dec(&egress_needed);
}
EXPORT_SYMBOL_GPL(net_dec_egress_queue);
#endif

1696
static struct static_key netstamp_needed __read_mostly;
1697
#ifdef HAVE_JUMP_LABEL
1698
/* We are not allowed to call static_key_slow_dec() from irq context
1699
 * If net_disable_timestamp() is called from irq context, defer the
1700
 * static_key_slow_dec() calls.
1701 1702 1703
 */
static atomic_t netstamp_needed_deferred;
#endif
L
Linus Torvalds 已提交
1704 1705 1706

void net_enable_timestamp(void)
{
1707 1708 1709 1710 1711
#ifdef HAVE_JUMP_LABEL
	int deferred = atomic_xchg(&netstamp_needed_deferred, 0);

	if (deferred) {
		while (--deferred)
1712
			static_key_slow_dec(&netstamp_needed);
1713 1714 1715
		return;
	}
#endif
1716
	static_key_slow_inc(&netstamp_needed);
L
Linus Torvalds 已提交
1717
}
E
Eric Dumazet 已提交
1718
EXPORT_SYMBOL(net_enable_timestamp);
L
Linus Torvalds 已提交
1719 1720 1721

void net_disable_timestamp(void)
{
1722 1723 1724 1725 1726 1727
#ifdef HAVE_JUMP_LABEL
	if (in_interrupt()) {
		atomic_inc(&netstamp_needed_deferred);
		return;
	}
#endif
1728
	static_key_slow_dec(&netstamp_needed);
L
Linus Torvalds 已提交
1729
}
E
Eric Dumazet 已提交
1730
EXPORT_SYMBOL(net_disable_timestamp);
L
Linus Torvalds 已提交
1731

E
Eric Dumazet 已提交
1732
static inline void net_timestamp_set(struct sk_buff *skb)
L
Linus Torvalds 已提交
1733
{
1734
	skb->tstamp.tv64 = 0;
1735
	if (static_key_false(&netstamp_needed))
1736
		__net_timestamp(skb);
L
Linus Torvalds 已提交
1737 1738
}

1739
#define net_timestamp_check(COND, SKB)			\
1740
	if (static_key_false(&netstamp_needed)) {		\
1741 1742 1743
		if ((COND) && !(SKB)->tstamp.tv64)	\
			__net_timestamp(SKB);		\
	}						\
E
Eric Dumazet 已提交
1744

1745
bool is_skb_forwardable(const struct net_device *dev, const struct sk_buff *skb)
1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763
{
	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;
}
1764
EXPORT_SYMBOL_GPL(is_skb_forwardable);
1765

H
Herbert Xu 已提交
1766 1767
int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
{
1768 1769
	if (skb_orphan_frags(skb, GFP_ATOMIC) ||
	    unlikely(!is_skb_forwardable(dev, skb))) {
H
Herbert Xu 已提交
1770 1771 1772 1773 1774 1775
		atomic_long_inc(&dev->rx_dropped);
		kfree_skb(skb);
		return NET_RX_DROP;
	}

	skb_scrub_packet(skb, true);
1776
	skb->priority = 0;
H
Herbert Xu 已提交
1777
	skb->protocol = eth_type_trans(skb, dev);
1778
	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
H
Herbert Xu 已提交
1779 1780 1781 1782 1783

	return 0;
}
EXPORT_SYMBOL_GPL(__dev_forward_skb);

1784 1785 1786 1787 1788 1789 1790 1791
/**
 * dev_forward_skb - loopback an skb to another netif
 *
 * @dev: destination network device
 * @skb: buffer to forward
 *
 * return values:
 *	NET_RX_SUCCESS	(no congestion)
1792
 *	NET_RX_DROP     (packet was dropped, but freed)
1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803
 *
 * 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
1804
	return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb);
1805 1806 1807
}
EXPORT_SYMBOL_GPL(dev_forward_skb);

1808 1809 1810 1811
static inline int deliver_skb(struct sk_buff *skb,
			      struct packet_type *pt_prev,
			      struct net_device *orig_dev)
{
1812 1813
	if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
		return -ENOMEM;
1814 1815 1816 1817
	atomic_inc(&skb->users);
	return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
}

1818 1819
static inline void deliver_ptype_list_skb(struct sk_buff *skb,
					  struct packet_type **pt,
1820 1821
					  struct net_device *orig_dev,
					  __be16 type,
1822 1823 1824 1825 1826 1827 1828 1829
					  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)
1830
			deliver_skb(skb, pt_prev, orig_dev);
1831 1832 1833 1834 1835
		pt_prev = ptype;
	}
	*pt = pt_prev;
}

1836 1837
static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
{
1838
	if (!ptype->af_packet_priv || !skb->sk)
1839 1840 1841 1842 1843 1844 1845 1846 1847 1848
		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
1849 1850 1851 1852 1853
/*
 *	Support routine. Sends outgoing frames to any network
 *	taps currently in use.
 */

1854
void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
L
Linus Torvalds 已提交
1855 1856
{
	struct packet_type *ptype;
1857 1858
	struct sk_buff *skb2 = NULL;
	struct packet_type *pt_prev = NULL;
1859
	struct list_head *ptype_list = &ptype_all;
1860

L
Linus Torvalds 已提交
1861
	rcu_read_lock();
1862 1863
again:
	list_for_each_entry_rcu(ptype, ptype_list, list) {
L
Linus Torvalds 已提交
1864 1865 1866
		/* Never send packets back to the socket
		 * they originated from - MvS (miquels@drinkel.ow.org)
		 */
1867 1868
		if (skb_loop_sk(ptype, skb))
			continue;
1869

1870 1871 1872 1873 1874
		if (pt_prev) {
			deliver_skb(skb2, pt_prev, skb->dev);
			pt_prev = ptype;
			continue;
		}
L
Linus Torvalds 已提交
1875

1876 1877 1878 1879
		/* need to clone skb, done only once */
		skb2 = skb_clone(skb, GFP_ATOMIC);
		if (!skb2)
			goto out_unlock;
1880

1881
		net_timestamp_set(skb2);
L
Linus Torvalds 已提交
1882

1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894
		/* 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
1895
		}
1896 1897 1898 1899 1900 1901 1902 1903 1904

		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
1905
	}
1906
out_unlock:
1907 1908
	if (pt_prev)
		pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
L
Linus Torvalds 已提交
1909 1910
	rcu_read_unlock();
}
1911
EXPORT_SYMBOL_GPL(dev_queue_xmit_nit);
L
Linus Torvalds 已提交
1912

1913 1914
/**
 * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925
 * @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
1926
static void netif_setup_tc(struct net_device *dev, unsigned int txq)
1927 1928 1929 1930 1931 1932
{
	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) {
1933
		pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
1934 1935 1936 1937 1938 1939 1940 1941 1942 1943
		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) {
1944 1945
			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);
1946 1947 1948 1949 1950
			netdev_set_prio_tc_map(dev, i, 0);
		}
	}
}

1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967
int netdev_txq_to_tc(struct net_device *dev, unsigned int txq)
{
	if (dev->num_tc) {
		struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
		int i;

		for (i = 0; i < TC_MAX_QUEUE; i++, tc++) {
			if ((txq - tc->offset) < tc->count)
				return i;
		}

		return -1;
	}

	return 0;
}

1968 1969 1970 1971 1972
#ifdef CONFIG_XPS
static DEFINE_MUTEX(xps_map_mutex);
#define xmap_dereference(P)		\
	rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))

1973 1974
static bool remove_xps_queue(struct xps_dev_maps *dev_maps,
			     int tci, u16 index)
1975
{
1976 1977
	struct xps_map *map = NULL;
	int pos;
1978

1979
	if (dev_maps)
1980 1981 1982
		map = xmap_dereference(dev_maps->cpu_map[tci]);
	if (!map)
		return false;
1983

1984 1985 1986 1987 1988 1989
	for (pos = map->len; pos--;) {
		if (map->queues[pos] != index)
			continue;

		if (map->len > 1) {
			map->queues[pos] = map->queues[--map->len];
1990
			break;
1991
		}
1992 1993 1994 1995

		RCU_INIT_POINTER(dev_maps->cpu_map[tci], NULL);
		kfree_rcu(map, rcu);
		return false;
1996 1997
	}

1998
	return true;
1999 2000
}

2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016
static bool remove_xps_queue_cpu(struct net_device *dev,
				 struct xps_dev_maps *dev_maps,
				 int cpu, u16 offset, u16 count)
{
	int i, j;

	for (i = count, j = offset; i--; j++) {
		if (!remove_xps_queue(dev_maps, cpu, j))
			break;
	}

	return i < 0;
}

static void netif_reset_xps_queues(struct net_device *dev, u16 offset,
				   u16 count)
2017 2018
{
	struct xps_dev_maps *dev_maps;
2019
	int cpu, i;
2020 2021 2022 2023 2024 2025 2026 2027
	bool active = false;

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

	if (!dev_maps)
		goto out_no_maps;

2028 2029 2030
	for_each_possible_cpu(cpu)
		active |= remove_xps_queue_cpu(dev, dev_maps, cpu,
					       offset, count);
2031 2032

	if (!active) {
2033 2034 2035 2036
		RCU_INIT_POINTER(dev->xps_maps, NULL);
		kfree_rcu(dev_maps, rcu);
	}

2037
	for (i = offset + (count - 1); count--; i--)
2038 2039 2040
		netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
					     NUMA_NO_NODE);

2041 2042 2043 2044
out_no_maps:
	mutex_unlock(&xps_map_mutex);
}

2045 2046 2047 2048 2049
static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
{
	netif_reset_xps_queues(dev, index, dev->num_tx_queues - index);
}

2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084
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;
}

2085 2086
int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
			u16 index)
2087
{
2088
	struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
2089 2090
	struct xps_map *map, *new_map;
	int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES);
2091 2092
	int cpu, numa_node_id = -2;
	bool active = false;
2093 2094 2095 2096 2097

	mutex_lock(&xps_map_mutex);

	dev_maps = xmap_dereference(dev->xps_maps);

2098 2099 2100 2101 2102 2103 2104
	/* 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);
2105 2106
		if (!new_dev_maps) {
			mutex_unlock(&xps_map_mutex);
2107
			return -ENOMEM;
2108
		}
2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122

		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;

2123
	for_each_possible_cpu(cpu) {
2124 2125 2126 2127 2128 2129 2130 2131 2132 2133
		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;
2134 2135 2136 2137 2138 2139
#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
2140 2141 2142 2143
		} 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);
2144
		}
2145

2146 2147
	}

2148 2149
	rcu_assign_pointer(dev->xps_maps, new_dev_maps);

2150
	/* Cleanup old maps */
2151 2152 2153 2154 2155 2156 2157
	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);
		}
2158

2159
		kfree_rcu(dev_maps, rcu);
2160 2161
	}

2162 2163
	dev_maps = new_dev_maps;
	active = true;
2164

2165 2166
out_no_new_maps:
	/* update Tx queue numa node */
2167 2168 2169 2170
	netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
				     (numa_node_id >= 0) ? numa_node_id :
				     NUMA_NO_NODE);

2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189
	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:
2190 2191 2192 2193
	mutex_unlock(&xps_map_mutex);

	return 0;
error:
2194 2195 2196 2197 2198 2199 2200 2201 2202
	/* 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);
	}

2203 2204 2205 2206 2207 2208 2209 2210
	mutex_unlock(&xps_map_mutex);

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

#endif
2211 2212
void netdev_reset_tc(struct net_device *dev)
{
2213 2214 2215
#ifdef CONFIG_XPS
	netif_reset_xps_queues_gt(dev, 0);
#endif
2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226
	dev->num_tc = 0;
	memset(dev->tc_to_txq, 0, sizeof(dev->tc_to_txq));
	memset(dev->prio_tc_map, 0, sizeof(dev->prio_tc_map));
}
EXPORT_SYMBOL(netdev_reset_tc);

int netdev_set_tc_queue(struct net_device *dev, u8 tc, u16 count, u16 offset)
{
	if (tc >= dev->num_tc)
		return -EINVAL;

2227 2228 2229
#ifdef CONFIG_XPS
	netif_reset_xps_queues(dev, offset, count);
#endif
2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240
	dev->tc_to_txq[tc].count = count;
	dev->tc_to_txq[tc].offset = offset;
	return 0;
}
EXPORT_SYMBOL(netdev_set_tc_queue);

int netdev_set_num_tc(struct net_device *dev, u8 num_tc)
{
	if (num_tc > TC_MAX_QUEUE)
		return -EINVAL;

2241 2242 2243
#ifdef CONFIG_XPS
	netif_reset_xps_queues_gt(dev, 0);
#endif
2244 2245 2246 2247 2248
	dev->num_tc = num_tc;
	return 0;
}
EXPORT_SYMBOL(netdev_set_num_tc);

2249 2250 2251 2252
/*
 * 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.
 */
2253
int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2254
{
T
Tom Herbert 已提交
2255 2256
	int rc;

2257 2258
	if (txq < 1 || txq > dev->num_tx_queues)
		return -EINVAL;
2259

2260 2261
	if (dev->reg_state == NETREG_REGISTERED ||
	    dev->reg_state == NETREG_UNREGISTERING) {
2262 2263
		ASSERT_RTNL();

T
Tom Herbert 已提交
2264 2265
		rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
						  txq);
T
Tom Herbert 已提交
2266 2267 2268
		if (rc)
			return rc;

2269 2270 2271
		if (dev->num_tc)
			netif_setup_tc(dev, txq);

2272
		if (txq < dev->real_num_tx_queues) {
2273
			qdisc_reset_all_tx_gt(dev, txq);
2274 2275 2276 2277
#ifdef CONFIG_XPS
			netif_reset_xps_queues_gt(dev, txq);
#endif
		}
2278
	}
2279 2280 2281

	dev->real_num_tx_queues = txq;
	return 0;
2282 2283
}
EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2284

2285
#ifdef CONFIG_SYSFS
2286 2287 2288 2289 2290 2291 2292
/**
 *	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
2293 2294
 *	negative error code.  If called before registration, it always
 *	succeeds.
2295 2296 2297 2298 2299
 */
int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
{
	int rc;

T
Tom Herbert 已提交
2300 2301 2302
	if (rxq < 1 || rxq > dev->num_rx_queues)
		return -EINVAL;

2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317
	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

2318 2319
/**
 * netif_get_num_default_rss_queues - default number of RSS queues
2320 2321 2322 2323
 *
 * This routine should set an upper limit on the number of RSS queues
 * used by default by multiqueue devices.
 */
2324
int netif_get_num_default_rss_queues(void)
2325
{
2326 2327
	return is_kdump_kernel() ?
		1 : min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
2328 2329 2330
}
EXPORT_SYMBOL(netif_get_num_default_rss_queues);

2331
static void __netif_reschedule(struct Qdisc *q)
2332
{
2333 2334
	struct softnet_data *sd;
	unsigned long flags;
2335

2336
	local_irq_save(flags);
2337
	sd = this_cpu_ptr(&softnet_data);
2338 2339 2340
	q->next_sched = NULL;
	*sd->output_queue_tailp = q;
	sd->output_queue_tailp = &q->next_sched;
2341 2342 2343 2344 2345 2346 2347 2348
	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);
2349 2350 2351
}
EXPORT_SYMBOL(__netif_schedule);

2352 2353 2354 2355 2356
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)
2357
{
2358 2359 2360
	return (struct dev_kfree_skb_cb *)skb->cb;
}

2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407
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);

2408
void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2409
{
2410
	unsigned long flags;
2411

2412 2413 2414 2415 2416
	if (likely(atomic_read(&skb->users) == 1)) {
		smp_rmb();
		atomic_set(&skb->users, 0);
	} else if (likely(!atomic_dec_and_test(&skb->users))) {
		return;
2417
	}
2418 2419 2420 2421 2422 2423
	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);
2424
}
2425
EXPORT_SYMBOL(__dev_kfree_skb_irq);
2426

2427
void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2428 2429
{
	if (in_irq() || irqs_disabled())
2430
		__dev_kfree_skb_irq(skb, reason);
2431 2432 2433
	else
		dev_kfree_skb(skb);
}
2434
EXPORT_SYMBOL(__dev_kfree_skb_any);
2435 2436


2437 2438 2439 2440 2441 2442
/**
 * netif_device_detach - mark device as removed
 * @dev: network device
 *
 * Mark device as removed from system and therefore no longer available.
 */
2443 2444 2445 2446
void netif_device_detach(struct net_device *dev)
{
	if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
	    netif_running(dev)) {
2447
		netif_tx_stop_all_queues(dev);
2448 2449 2450 2451
	}
}
EXPORT_SYMBOL(netif_device_detach);

2452 2453 2454 2455 2456 2457
/**
 * netif_device_attach - mark device as attached
 * @dev: network device
 *
 * Mark device as attached from system and restart if needed.
 */
2458 2459 2460 2461
void netif_device_attach(struct net_device *dev)
{
	if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
	    netif_running(dev)) {
2462
		netif_tx_wake_all_queues(dev);
2463
		__netdev_watchdog_up(dev);
2464 2465 2466 2467
	}
}
EXPORT_SYMBOL(netif_device_attach);

J
Jiri Pirko 已提交
2468 2469 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
/*
 * Returns a Tx hash based on the given packet descriptor a Tx queues' number
 * to be used as a distribution range.
 */
u16 __skb_tx_hash(const struct net_device *dev, struct sk_buff *skb,
		  unsigned int num_tx_queues)
{
	u32 hash;
	u16 qoffset = 0;
	u16 qcount = num_tx_queues;

	if (skb_rx_queue_recorded(skb)) {
		hash = skb_get_rx_queue(skb);
		while (unlikely(hash >= num_tx_queues))
			hash -= num_tx_queues;
		return hash;
	}

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

	return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset;
}
EXPORT_SYMBOL(__skb_tx_hash);

2496 2497
static void skb_warn_bad_offload(const struct sk_buff *skb)
{
W
Wei Tang 已提交
2498
	static const netdev_features_t null_features;
2499
	struct net_device *dev = skb->dev;
2500
	const char *name = "";
2501

2502 2503 2504
	if (!net_ratelimit())
		return;

2505 2506 2507 2508 2509 2510
	if (dev) {
		if (dev->dev.parent)
			name = dev_driver_string(dev->dev.parent);
		else
			name = netdev_name(dev);
	}
2511 2512
	WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
	     "gso_type=%d ip_summed=%d\n",
2513
	     name, dev ? &dev->features : &null_features,
2514
	     skb->sk ? &skb->sk->sk_route_caps : &null_features,
2515 2516 2517 2518
	     skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
	     skb_shinfo(skb)->gso_type, skb->ip_summed);
}

L
Linus Torvalds 已提交
2519 2520 2521 2522
/*
 * Invalidate hardware checksum when packet is to be mangled, and
 * complete checksum manually on outgoing path.
 */
2523
int skb_checksum_help(struct sk_buff *skb)
L
Linus Torvalds 已提交
2524
{
2525
	__wsum csum;
2526
	int ret = 0, offset;
L
Linus Torvalds 已提交
2527

2528
	if (skb->ip_summed == CHECKSUM_COMPLETE)
2529 2530 2531
		goto out_set_summed;

	if (unlikely(skb_shinfo(skb)->gso_size)) {
2532 2533
		skb_warn_bad_offload(skb);
		return -EINVAL;
L
Linus Torvalds 已提交
2534 2535
	}

2536 2537 2538 2539 2540 2541 2542 2543 2544
	/* 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;
	}

2545
	offset = skb_checksum_start_offset(skb);
2546 2547 2548 2549 2550 2551 2552 2553
	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
2554 2555 2556 2557 2558
		ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
		if (ret)
			goto out;
	}

2559
	*(__sum16 *)(skb->data + offset) = csum_fold(csum);
2560
out_set_summed:
L
Linus Torvalds 已提交
2561
	skb->ip_summed = CHECKSUM_NONE;
2562
out:
L
Linus Torvalds 已提交
2563 2564
	return ret;
}
E
Eric Dumazet 已提交
2565
EXPORT_SYMBOL(skb_checksum_help);
L
Linus Torvalds 已提交
2566

2567
__be16 skb_network_protocol(struct sk_buff *skb, int *depth)
2568
{
A
Al Viro 已提交
2569
	__be16 type = skb->protocol;
2570

2571 2572 2573 2574 2575 2576 2577 2578 2579 2580 2581
	/* 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;
	}

2582
	return __vlan_get_protocol(skb, type, depth);
2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594
}

/**
 *	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;
2595 2596
	int vlan_depth = skb->mac_len;
	__be16 type = skb_network_protocol(skb, &vlan_depth);
2597 2598 2599 2600

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

2601
	__skb_pull(skb, vlan_depth);
2602 2603

	rcu_read_lock();
2604
	list_for_each_entry_rcu(ptype, &offload_base, list) {
2605 2606
		if (ptype->type == type && ptype->callbacks.gso_segment) {
			segs = ptype->callbacks.gso_segment(skb, features);
2607 2608 2609 2610 2611
			break;
		}
	}
	rcu_read_unlock();

2612
	__skb_push(skb, skb->data - skb_mac_header(skb));
2613

2614 2615
	return segs;
}
2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638
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.
2639 2640
 *
 *	Segmentation preserves SKB_SGO_CB_OFFSET bytes of previous skb cb.
2641 2642 2643 2644 2645 2646 2647 2648 2649
 */
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);

2650 2651
		err = skb_cow_head(skb, 0);
		if (err < 0)
2652 2653 2654
			return ERR_PTR(err);
	}

2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667
	/* Only report GSO partial support if it will enable us to
	 * support segmentation on this frame without needing additional
	 * work.
	 */
	if (features & NETIF_F_GSO_PARTIAL) {
		netdev_features_t partial_features = NETIF_F_GSO_ROBUST;
		struct net_device *dev = skb->dev;

		partial_features |= dev->features & dev->gso_partial_features;
		if (!skb_gso_ok(skb, features | partial_features))
			features &= ~NETIF_F_GSO_PARTIAL;
	}

2668 2669 2670
	BUILD_BUG_ON(SKB_SGO_CB_OFFSET +
		     sizeof(*SKB_GSO_CB(skb)) > sizeof(skb->cb));

2671
	SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2672 2673
	SKB_GSO_CB(skb)->encap_level = 0;

2674 2675 2676 2677 2678
	skb_reset_mac_header(skb);
	skb_reset_mac_len(skb);

	return skb_mac_gso_segment(skb, features);
}
2679
EXPORT_SYMBOL(__skb_gso_segment);
2680

2681 2682 2683 2684 2685
/* Take action when hardware reception checksum errors are detected. */
#ifdef CONFIG_BUG
void netdev_rx_csum_fault(struct net_device *dev)
{
	if (net_ratelimit()) {
2686
		pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2687 2688 2689 2690 2691 2692
		dump_stack();
	}
}
EXPORT_SYMBOL(netdev_rx_csum_fault);
#endif

L
Linus Torvalds 已提交
2693 2694 2695 2696 2697
/* 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.
 */

2698
static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
L
Linus Torvalds 已提交
2699
{
2700
#ifdef CONFIG_HIGHMEM
L
Linus Torvalds 已提交
2701
	int i;
2702
	if (!(dev->features & NETIF_F_HIGHDMA)) {
2703 2704 2705
		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)))
2706
				return 1;
2707
		}
2708
	}
L
Linus Torvalds 已提交
2709

2710 2711
	if (PCI_DMA_BUS_IS_PHYS) {
		struct device *pdev = dev->dev.parent;
L
Linus Torvalds 已提交
2712

E
Eric Dumazet 已提交
2713 2714
		if (!pdev)
			return 0;
2715
		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2716 2717
			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
			dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2718 2719 2720 2721
			if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
				return 1;
		}
	}
2722
#endif
L
Linus Torvalds 已提交
2723 2724 2725
	return 0;
}

2726 2727 2728
/* 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
2729
#if IS_ENABLED(CONFIG_NET_MPLS_GSO)
2730 2731 2732 2733
static netdev_features_t net_mpls_features(struct sk_buff *skb,
					   netdev_features_t features,
					   __be16 type)
{
2734
	if (eth_p_mpls(type))
2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747
		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

2748
static netdev_features_t harmonize_features(struct sk_buff *skb,
2749
	netdev_features_t features)
2750
{
2751
	int tmp;
2752 2753 2754 2755
	__be16 type;

	type = skb_network_protocol(skb, &tmp);
	features = net_mpls_features(skb, features, type);
2756

2757
	if (skb->ip_summed != CHECKSUM_NONE &&
2758
	    !can_checksum_protocol(features, type)) {
2759
		features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
2760
	} else if (illegal_highdma(skb->dev, skb)) {
2761 2762 2763 2764 2765 2766
		features &= ~NETIF_F_SG;
	}

	return features;
}

2767 2768 2769 2770 2771 2772 2773 2774
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);

2775 2776 2777 2778 2779 2780 2781
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);
}

2782 2783 2784 2785 2786 2787 2788 2789 2790
static netdev_features_t gso_features_check(const struct sk_buff *skb,
					    struct net_device *dev,
					    netdev_features_t features)
{
	u16 gso_segs = skb_shinfo(skb)->gso_segs;

	if (gso_segs > dev->gso_max_segs)
		return features & ~NETIF_F_GSO_MASK;

2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801
	/* Support for GSO partial features requires software
	 * intervention before we can actually process the packets
	 * so we need to strip support for any partial features now
	 * and we can pull them back in after we have partially
	 * segmented the frame.
	 */
	if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL))
		features &= ~dev->gso_partial_features;

	/* Make sure to clear the IPv4 ID mangling feature if the
	 * IPv4 header has the potential to be fragmented.
2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813
	 */
	if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) {
		struct iphdr *iph = skb->encapsulation ?
				    inner_ip_hdr(skb) : ip_hdr(skb);

		if (!(iph->frag_off & htons(IP_DF)))
			features &= ~NETIF_F_TSO_MANGLEID;
	}

	return features;
}

2814
netdev_features_t netif_skb_features(struct sk_buff *skb)
2815
{
2816
	struct net_device *dev = skb->dev;
2817
	netdev_features_t features = dev->features;
2818

2819 2820
	if (skb_is_gso(skb))
		features = gso_features_check(skb, dev, features);
2821

2822 2823 2824 2825 2826 2827 2828
	/* 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;

2829 2830 2831 2832 2833
	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);
2834

2835 2836 2837
	if (dev->netdev_ops->ndo_features_check)
		features &= dev->netdev_ops->ndo_features_check(skb, dev,
								features);
2838 2839
	else
		features &= dflt_features_check(skb, dev, features);
2840

2841
	return harmonize_features(skb, features);
2842
}
2843
EXPORT_SYMBOL(netif_skb_features);
2844

2845
static int xmit_one(struct sk_buff *skb, struct net_device *dev,
2846
		    struct netdev_queue *txq, bool more)
2847
{
2848 2849
	unsigned int len;
	int rc;
2850

2851
	if (!list_empty(&ptype_all) || !list_empty(&dev->ptype_all))
2852
		dev_queue_xmit_nit(skb, dev);
2853

2854 2855
	len = skb->len;
	trace_net_dev_start_xmit(skb, dev);
2856
	rc = netdev_start_xmit(skb, dev, txq, more);
2857
	trace_net_dev_xmit(skb, rc, dev, len);
E
Eric Dumazet 已提交
2858

2859 2860
	return rc;
}
2861

2862 2863
struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev,
				    struct netdev_queue *txq, int *ret)
2864 2865 2866
{
	struct sk_buff *skb = first;
	int rc = NETDEV_TX_OK;
2867

2868 2869
	while (skb) {
		struct sk_buff *next = skb->next;
2870

2871
		skb->next = NULL;
2872
		rc = xmit_one(skb, dev, txq, next != NULL);
2873 2874 2875 2876
		if (unlikely(!dev_xmit_complete(rc))) {
			skb->next = next;
			goto out;
		}
2877

2878 2879 2880 2881
		skb = next;
		if (netif_xmit_stopped(txq) && skb) {
			rc = NETDEV_TX_BUSY;
			break;
2882
		}
2883
	}
2884

2885 2886 2887 2888
out:
	*ret = rc;
	return skb;
}
2889

E
Eric Dumazet 已提交
2890 2891
static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
					  netdev_features_t features)
2892
{
2893
	if (skb_vlan_tag_present(skb) &&
2894 2895
	    !vlan_hw_offload_capable(features, skb->vlan_proto))
		skb = __vlan_hwaccel_push_inside(skb);
2896 2897
	return skb;
}
2898

2899
static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev)
2900 2901
{
	netdev_features_t features;
2902

2903 2904 2905 2906
	features = netif_skb_features(skb);
	skb = validate_xmit_vlan(skb, features);
	if (unlikely(!skb))
		goto out_null;
2907

2908
	if (netif_needs_gso(skb, features)) {
2909 2910 2911
		struct sk_buff *segs;

		segs = skb_gso_segment(skb, features);
2912
		if (IS_ERR(segs)) {
2913
			goto out_kfree_skb;
2914 2915 2916
		} else if (segs) {
			consume_skb(skb);
			skb = segs;
2917
		}
2918 2919 2920 2921
	} else {
		if (skb_needs_linearize(skb, features) &&
		    __skb_linearize(skb))
			goto out_kfree_skb;
2922

2923 2924 2925 2926 2927 2928 2929 2930 2931 2932 2933
		/* 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));
2934
			if (!(features & NETIF_F_CSUM_MASK) &&
2935 2936
			    skb_checksum_help(skb))
				goto out_kfree_skb;
2937
		}
2938
	}
2939

2940
	return skb;
2941

2942 2943
out_kfree_skb:
	kfree_skb(skb);
2944
out_null:
E
Eric Dumazet 已提交
2945
	atomic_long_inc(&dev->tx_dropped);
2946 2947
	return NULL;
}
2948

2949 2950 2951 2952
struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev)
{
	struct sk_buff *next, *head = NULL, *tail;

2953
	for (; skb != NULL; skb = next) {
2954 2955
		next = skb->next;
		skb->next = NULL;
2956 2957 2958 2959

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

2960
		skb = validate_xmit_skb(skb, dev);
2961 2962
		if (!skb)
			continue;
2963

2964 2965 2966 2967 2968 2969 2970 2971
		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;
2972 2973
	}
	return head;
2974
}
2975
EXPORT_SYMBOL_GPL(validate_xmit_skb_list);
2976

2977 2978 2979 2980 2981 2982 2983 2984 2985 2986
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)  {
2987
		unsigned int hdr_len;
2988
		u16 gso_segs = shinfo->gso_segs;
2989

2990 2991 2992 2993
		/* mac layer + network layer */
		hdr_len = skb_transport_header(skb) - skb_mac_header(skb);

		/* + transport layer */
2994 2995 2996 2997
		if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
			hdr_len += tcp_hdrlen(skb);
		else
			hdr_len += sizeof(struct udphdr);
2998 2999 3000 3001 3002 3003

		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;
3004 3005 3006
	}
}

3007 3008 3009 3010 3011
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);
3012
	struct sk_buff *to_free = NULL;
E
Eric Dumazet 已提交
3013
	bool contended;
3014 3015
	int rc;

E
Eric Dumazet 已提交
3016
	qdisc_calculate_pkt_len(skb, q);
3017 3018 3019
	/*
	 * Heuristic to force contended enqueues to serialize on a
	 * separate lock before trying to get qdisc main lock.
3020
	 * This permits qdisc->running owner to get the lock more
Y
Ying Xue 已提交
3021
	 * often and dequeue packets faster.
3022
	 */
E
Eric Dumazet 已提交
3023
	contended = qdisc_is_running(q);
3024 3025 3026
	if (unlikely(contended))
		spin_lock(&q->busylock);

3027 3028
	spin_lock(root_lock);
	if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
3029
		__qdisc_drop(skb, &to_free);
3030 3031
		rc = NET_XMIT_DROP;
	} else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
3032
		   qdisc_run_begin(q)) {
3033 3034 3035 3036 3037
		/*
		 * 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.
		 */
3038 3039 3040

		qdisc_bstats_update(q, skb);

3041
		if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) {
3042 3043 3044 3045
			if (unlikely(contended)) {
				spin_unlock(&q->busylock);
				contended = false;
			}
3046
			__qdisc_run(q);
3047
		} else
3048
			qdisc_run_end(q);
3049 3050 3051

		rc = NET_XMIT_SUCCESS;
	} else {
3052
		rc = q->enqueue(skb, q, &to_free) & NET_XMIT_MASK;
3053 3054 3055 3056 3057 3058 3059
		if (qdisc_run_begin(q)) {
			if (unlikely(contended)) {
				spin_unlock(&q->busylock);
				contended = false;
			}
			__qdisc_run(q);
		}
3060 3061
	}
	spin_unlock(root_lock);
3062 3063
	if (unlikely(to_free))
		kfree_skb_list(to_free);
3064 3065
	if (unlikely(contended))
		spin_unlock(&q->busylock);
3066 3067 3068
	return rc;
}

3069
#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
3070 3071
static void skb_update_prio(struct sk_buff *skb)
{
I
Igor Maravic 已提交
3072
	struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
3073

3074
	if (!skb->priority && skb->sk && map) {
3075 3076
		unsigned int prioidx =
			sock_cgroup_prioidx(&skb->sk->sk_cgrp_data);
3077 3078 3079 3080

		if (prioidx < map->priomap_len)
			skb->priority = map->priomap[prioidx];
	}
3081 3082 3083 3084 3085
}
#else
#define skb_update_prio(skb)
#endif

3086 3087 3088
DEFINE_PER_CPU(int, xmit_recursion);
EXPORT_SYMBOL(xmit_recursion);

3089 3090
/**
 *	dev_loopback_xmit - loop back @skb
3091 3092
 *	@net: network namespace this loopback is happening in
 *	@sk:  sk needed to be a netfilter okfn
3093 3094
 *	@skb: buffer to transmit
 */
3095
int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb)
3096 3097 3098 3099 3100 3101 3102 3103 3104 3105 3106 3107
{
	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);

D
Daniel Borkmann 已提交
3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130
#ifdef CONFIG_NET_EGRESS
static struct sk_buff *
sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev)
{
	struct tcf_proto *cl = rcu_dereference_bh(dev->egress_cl_list);
	struct tcf_result cl_res;

	if (!cl)
		return skb;

	/* skb->tc_verd and qdisc_skb_cb(skb)->pkt_len were already set
	 * earlier by the caller.
	 */
	qdisc_bstats_cpu_update(cl->q, skb);

	switch (tc_classify(skb, cl, &cl_res, false)) {
	case TC_ACT_OK:
	case TC_ACT_RECLASSIFY:
		skb->tc_index = TC_H_MIN(cl_res.classid);
		break;
	case TC_ACT_SHOT:
		qdisc_qstats_cpu_drop(cl->q);
		*ret = NET_XMIT_DROP;
3131 3132
		kfree_skb(skb);
		return NULL;
D
Daniel Borkmann 已提交
3133 3134 3135
	case TC_ACT_STOLEN:
	case TC_ACT_QUEUED:
		*ret = NET_XMIT_SUCCESS;
3136
		consume_skb(skb);
D
Daniel Borkmann 已提交
3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150
		return NULL;
	case TC_ACT_REDIRECT:
		/* No need to push/pop skb's mac_header here on egress! */
		skb_do_redirect(skb);
		*ret = NET_XMIT_SUCCESS;
		return NULL;
	default:
		break;
	}

	return skb;
}
#endif /* CONFIG_NET_EGRESS */

3151 3152 3153 3154 3155 3156 3157 3158 3159 3160 3161 3162 3163 3164 3165 3166 3167 3168 3169 3170 3171 3172 3173 3174 3175 3176 3177 3178 3179 3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192
static inline int get_xps_queue(struct net_device *dev, struct sk_buff *skb)
{
#ifdef CONFIG_XPS
	struct xps_dev_maps *dev_maps;
	struct xps_map *map;
	int queue_index = -1;

	rcu_read_lock();
	dev_maps = rcu_dereference(dev->xps_maps);
	if (dev_maps) {
		map = rcu_dereference(
		    dev_maps->cpu_map[skb->sender_cpu - 1]);
		if (map) {
			if (map->len == 1)
				queue_index = map->queues[0];
			else
				queue_index = map->queues[reciprocal_scale(skb_get_hash(skb),
									   map->len)];
			if (unlikely(queue_index >= dev->real_num_tx_queues))
				queue_index = -1;
		}
	}
	rcu_read_unlock();

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

static u16 __netdev_pick_tx(struct net_device *dev, struct sk_buff *skb)
{
	struct sock *sk = skb->sk;
	int queue_index = sk_tx_queue_get(sk);

	if (queue_index < 0 || skb->ooo_okay ||
	    queue_index >= dev->real_num_tx_queues) {
		int new_index = get_xps_queue(dev, skb);
		if (new_index < 0)
			new_index = skb_tx_hash(dev, skb);

		if (queue_index != new_index && sk &&
3193
		    sk_fullsock(sk) &&
3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209
		    rcu_access_pointer(sk->sk_dst_cache))
			sk_tx_queue_set(sk, new_index);

		queue_index = new_index;
	}

	return queue_index;
}

struct netdev_queue *netdev_pick_tx(struct net_device *dev,
				    struct sk_buff *skb,
				    void *accel_priv)
{
	int queue_index = 0;

#ifdef CONFIG_XPS
3210 3211 3212
	u32 sender_cpu = skb->sender_cpu - 1;

	if (sender_cpu >= (u32)NR_CPUS)
3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231
		skb->sender_cpu = raw_smp_processor_id() + 1;
#endif

	if (dev->real_num_tx_queues != 1) {
		const struct net_device_ops *ops = dev->netdev_ops;
		if (ops->ndo_select_queue)
			queue_index = ops->ndo_select_queue(dev, skb, accel_priv,
							    __netdev_pick_tx);
		else
			queue_index = __netdev_pick_tx(dev, skb);

		if (!accel_priv)
			queue_index = netdev_cap_txqueue(dev, queue_index);
	}

	skb_set_queue_mapping(skb, queue_index);
	return netdev_get_tx_queue(dev, queue_index);
}

3232
/**
3233
 *	__dev_queue_xmit - transmit a buffer
3234
 *	@skb: buffer to transmit
3235
 *	@accel_priv: private data used for L2 forwarding offload
3236 3237 3238 3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257
 *
 *	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
 */
3258
static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
L
Linus Torvalds 已提交
3259 3260
{
	struct net_device *dev = skb->dev;
3261
	struct netdev_queue *txq;
L
Linus Torvalds 已提交
3262 3263 3264
	struct Qdisc *q;
	int rc = -ENOMEM;

3265 3266
	skb_reset_mac_header(skb);

3267 3268 3269
	if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
		__skb_tstamp_tx(skb, NULL, skb->sk, SCM_TSTAMP_SCHED);

3270 3271
	/* Disable soft irqs for various locks below. Also
	 * stops preemption for RCU.
L
Linus Torvalds 已提交
3272
	 */
3273
	rcu_read_lock_bh();
L
Linus Torvalds 已提交
3274

3275 3276
	skb_update_prio(skb);

D
Daniel Borkmann 已提交
3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287
	qdisc_pkt_len_init(skb);
#ifdef CONFIG_NET_CLS_ACT
	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
# ifdef CONFIG_NET_EGRESS
	if (static_key_false(&egress_needed)) {
		skb = sch_handle_egress(skb, &rc, dev);
		if (!skb)
			goto out;
	}
# endif
#endif
3288 3289 3290 3291 3292 3293 3294 3295
	/* 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);

3296
	txq = netdev_pick_tx(dev, skb, accel_priv);
3297
	q = rcu_dereference_bh(txq->qdisc);
3298

3299
	trace_net_dev_queue(skb);
L
Linus Torvalds 已提交
3300
	if (q->enqueue) {
3301
		rc = __dev_xmit_skb(skb, q, dev, txq);
3302
		goto out;
L
Linus Torvalds 已提交
3303 3304 3305 3306 3307
	}

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

H
Herbert Xu 已提交
3308 3309
	   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
3310 3311 3312 3313 3314 3315 3316 3317 3318 3319
	   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 */

3320
		if (txq->xmit_lock_owner != cpu) {
3321 3322
			if (unlikely(__this_cpu_read(xmit_recursion) >
				     XMIT_RECURSION_LIMIT))
3323 3324
				goto recursion_alert;

3325 3326
			skb = validate_xmit_skb(skb, dev);
			if (!skb)
E
Eric Dumazet 已提交
3327
				goto out;
3328

3329
			HARD_TX_LOCK(dev, txq, cpu);
L
Linus Torvalds 已提交
3330

3331
			if (!netif_xmit_stopped(txq)) {
3332
				__this_cpu_inc(xmit_recursion);
3333
				skb = dev_hard_start_xmit(skb, dev, txq, &rc);
3334
				__this_cpu_dec(xmit_recursion);
3335
				if (dev_xmit_complete(rc)) {
3336
					HARD_TX_UNLOCK(dev, txq);
L
Linus Torvalds 已提交
3337 3338 3339
					goto out;
				}
			}
3340
			HARD_TX_UNLOCK(dev, txq);
3341 3342
			net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
					     dev->name);
L
Linus Torvalds 已提交
3343 3344
		} else {
			/* Recursion is detected! It is possible,
3345 3346 3347
			 * unfortunately
			 */
recursion_alert:
3348 3349
			net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
					     dev->name);
L
Linus Torvalds 已提交
3350 3351 3352 3353
		}
	}

	rc = -ENETDOWN;
3354
	rcu_read_unlock_bh();
L
Linus Torvalds 已提交
3355

3356
	atomic_long_inc(&dev->tx_dropped);
3357
	kfree_skb_list(skb);
L
Linus Torvalds 已提交
3358 3359
	return rc;
out:
3360
	rcu_read_unlock_bh();
L
Linus Torvalds 已提交
3361 3362
	return rc;
}
3363

3364
int dev_queue_xmit(struct sk_buff *skb)
3365 3366 3367
{
	return __dev_queue_xmit(skb, NULL);
}
3368
EXPORT_SYMBOL(dev_queue_xmit);
L
Linus Torvalds 已提交
3369

3370 3371 3372 3373 3374 3375
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
3376 3377 3378 3379 3380

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

3381
int netdev_max_backlog __read_mostly = 1000;
E
Eric Dumazet 已提交
3382 3383
EXPORT_SYMBOL(netdev_max_backlog);

E
Eric Dumazet 已提交
3384
int netdev_tstamp_prequeue __read_mostly = 1;
3385 3386
int netdev_budget __read_mostly = 300;
int weight_p __read_mostly = 64;            /* old backlog weight */
L
Linus Torvalds 已提交
3387

E
Eric Dumazet 已提交
3388 3389 3390 3391 3392 3393 3394 3395
/* 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);
}

3396 3397 3398
#ifdef CONFIG_RPS

/* One global table that all flow-based protocols share. */
E
Eric Dumazet 已提交
3399
struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
3400
EXPORT_SYMBOL(rps_sock_flow_table);
3401 3402
u32 rps_cpu_mask __read_mostly;
EXPORT_SYMBOL(rps_cpu_mask);
3403

3404
struct static_key rps_needed __read_mostly;
3405
EXPORT_SYMBOL(rps_needed);
3406

3407 3408 3409 3410
static struct rps_dev_flow *
set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
	    struct rps_dev_flow *rflow, u16 next_cpu)
{
3411
	if (next_cpu < nr_cpu_ids) {
3412 3413 3414 3415 3416 3417 3418 3419 3420
#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? */
3421 3422
		if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
		    !(dev->features & NETIF_F_NTUPLE))
3423 3424 3425 3426 3427 3428 3429 3430 3431
			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;
3432
		flow_id = skb_get_hash(skb) & flow_table->mask;
3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 3444
		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 =
3445
			per_cpu(softnet_data, next_cpu).input_queue_head;
3446 3447
	}

3448
	rflow->cpu = next_cpu;
3449 3450 3451
	return rflow;
}

3452 3453 3454 3455 3456 3457 3458 3459
/*
 * 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)
{
3460 3461
	const struct rps_sock_flow_table *sock_flow_table;
	struct netdev_rx_queue *rxqueue = dev->_rx;
3462
	struct rps_dev_flow_table *flow_table;
3463
	struct rps_map *map;
3464
	int cpu = -1;
3465
	u32 tcpu;
3466
	u32 hash;
3467 3468 3469

	if (skb_rx_queue_recorded(skb)) {
		u16 index = skb_get_rx_queue(skb);
3470

3471 3472 3473 3474 3475
		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);
3476 3477
			goto done;
		}
3478 3479
		rxqueue += index;
	}
3480

3481 3482 3483
	/* 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
3484
	map = rcu_dereference(rxqueue->rps_map);
3485
	if (!flow_table && !map)
3486 3487
		goto done;

3488
	skb_reset_network_header(skb);
3489 3490
	hash = skb_get_hash(skb);
	if (!hash)
3491 3492
		goto done;

T
Tom Herbert 已提交
3493 3494 3495
	sock_flow_table = rcu_dereference(rps_sock_flow_table);
	if (flow_table && sock_flow_table) {
		struct rps_dev_flow *rflow;
3496 3497 3498 3499 3500 3501 3502
		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
3503

3504 3505 3506 3507 3508
		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
		 */
3509
		rflow = &flow_table->flows[hash & flow_table->mask];
T
Tom Herbert 已提交
3510 3511 3512 3513 3514 3515
		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:
3516
		 *   - Current CPU is unset (>= nr_cpu_ids).
T
Tom Herbert 已提交
3517 3518 3519 3520 3521 3522 3523
		 *   - 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) &&
3524
		    (tcpu >= nr_cpu_ids || !cpu_online(tcpu) ||
T
Tom Herbert 已提交
3525
		     ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
3526 3527
		      rflow->last_qtail)) >= 0)) {
			tcpu = next_cpu;
3528
			rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3529
		}
3530

3531
		if (tcpu < nr_cpu_ids && cpu_online(tcpu)) {
T
Tom Herbert 已提交
3532 3533 3534 3535 3536 3537
			*rflowp = rflow;
			cpu = tcpu;
			goto done;
		}
	}

3538 3539
try_rps:

T
Tom Herbert 已提交
3540
	if (map) {
3541
		tcpu = map->cpus[reciprocal_scale(hash, map->len)];
T
Tom Herbert 已提交
3542 3543 3544 3545 3546 3547 3548 3549 3550 3551
		if (cpu_online(tcpu)) {
			cpu = tcpu;
			goto done;
		}
	}

done:
	return cpu;
}

3552 3553 3554 3555 3556 3557 3558 3559 3560 3561 3562 3563 3564 3565 3566 3567 3568 3569 3570 3571
#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;
3572
	unsigned int cpu;
3573 3574 3575 3576 3577 3578

	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);
3579
		if (rflow->filter == filter_id && cpu < nr_cpu_ids &&
3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591
		    ((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
3592
/* Called from hardirq (IPI) context */
E
Eric Dumazet 已提交
3593
static void rps_trigger_softirq(void *data)
T
Tom Herbert 已提交
3594
{
E
Eric Dumazet 已提交
3595 3596
	struct softnet_data *sd = data;

E
Eric Dumazet 已提交
3597
	____napi_schedule(sd, &sd->backlog);
C
Changli Gao 已提交
3598
	sd->received_rps++;
T
Tom Herbert 已提交
3599
}
E
Eric Dumazet 已提交
3600

T
Tom Herbert 已提交
3601
#endif /* CONFIG_RPS */
T
Tom Herbert 已提交
3602

E
Eric Dumazet 已提交
3603 3604 3605 3606 3607 3608 3609 3610
/*
 * 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
3611
	struct softnet_data *mysd = this_cpu_ptr(&softnet_data);
E
Eric Dumazet 已提交
3612 3613 3614 3615 3616 3617 3618 3619 3620 3621 3622 3623

	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;
}

3624 3625 3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637
#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;

3638
	sd = this_cpu_ptr(&softnet_data);
3639 3640 3641 3642

	rcu_read_lock();
	fl = rcu_dereference(sd->flow_limit);
	if (fl) {
3643
		new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3644 3645 3646 3647 3648 3649 3650 3651 3652 3653 3654 3655 3656 3657 3658 3659 3660 3661 3662 3663
		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
3664 3665 3666 3667
/*
 * 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
3668 3669
static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
			      unsigned int *qtail)
T
Tom Herbert 已提交
3670
{
E
Eric Dumazet 已提交
3671
	struct softnet_data *sd;
T
Tom Herbert 已提交
3672
	unsigned long flags;
3673
	unsigned int qlen;
T
Tom Herbert 已提交
3674

E
Eric Dumazet 已提交
3675
	sd = &per_cpu(softnet_data, cpu);
T
Tom Herbert 已提交
3676 3677 3678

	local_irq_save(flags);

E
Eric Dumazet 已提交
3679
	rps_lock(sd);
3680 3681
	if (!netif_running(skb->dev))
		goto drop;
3682 3683
	qlen = skb_queue_len(&sd->input_pkt_queue);
	if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3684
		if (qlen) {
T
Tom Herbert 已提交
3685
enqueue:
E
Eric Dumazet 已提交
3686
			__skb_queue_tail(&sd->input_pkt_queue, skb);
3687
			input_queue_tail_incr_save(sd, qtail);
E
Eric Dumazet 已提交
3688
			rps_unlock(sd);
3689
			local_irq_restore(flags);
T
Tom Herbert 已提交
3690 3691 3692
			return NET_RX_SUCCESS;
		}

3693 3694 3695 3696
		/* 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
3697
			if (!rps_ipi_queued(sd))
E
Eric Dumazet 已提交
3698
				____napi_schedule(sd, &sd->backlog);
T
Tom Herbert 已提交
3699 3700 3701 3702
		}
		goto enqueue;
	}

3703
drop:
C
Changli Gao 已提交
3704
	sd->dropped++;
E
Eric Dumazet 已提交
3705
	rps_unlock(sd);
T
Tom Herbert 已提交
3706 3707 3708

	local_irq_restore(flags);

3709
	atomic_long_inc(&skb->dev->rx_dropped);
T
Tom Herbert 已提交
3710 3711 3712
	kfree_skb(skb);
	return NET_RX_DROP;
}
L
Linus Torvalds 已提交
3713

3714
static int netif_rx_internal(struct sk_buff *skb)
L
Linus Torvalds 已提交
3715
{
3716
	int ret;
L
Linus Torvalds 已提交
3717

3718
	net_timestamp_check(netdev_tstamp_prequeue, skb);
L
Linus Torvalds 已提交
3719

3720
	trace_netif_rx(skb);
E
Eric Dumazet 已提交
3721
#ifdef CONFIG_RPS
3722
	if (static_key_false(&rps_needed)) {
T
Tom Herbert 已提交
3723
		struct rps_dev_flow voidflow, *rflow = &voidflow;
3724 3725
		int cpu;

3726
		preempt_disable();
3727
		rcu_read_lock();
T
Tom Herbert 已提交
3728 3729

		cpu = get_rps_cpu(skb->dev, skb, &rflow);
3730 3731
		if (cpu < 0)
			cpu = smp_processor_id();
T
Tom Herbert 已提交
3732 3733 3734

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

3735
		rcu_read_unlock();
3736
		preempt_enable();
3737 3738
	} else
#endif
T
Tom Herbert 已提交
3739 3740 3741 3742 3743
	{
		unsigned int qtail;
		ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
		put_cpu();
	}
3744
	return ret;
L
Linus Torvalds 已提交
3745
}
3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 3760 3761 3762 3763 3764 3765 3766 3767

/**
 *	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
3768
EXPORT_SYMBOL(netif_rx);
L
Linus Torvalds 已提交
3769 3770 3771 3772 3773

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

3774 3775
	trace_netif_rx_ni_entry(skb);

L
Linus Torvalds 已提交
3776
	preempt_disable();
3777
	err = netif_rx_internal(skb);
L
Linus Torvalds 已提交
3778 3779 3780 3781 3782 3783 3784 3785
	if (local_softirq_pending())
		do_softirq();
	preempt_enable();

	return err;
}
EXPORT_SYMBOL(netif_rx_ni);

3786
static __latent_entropy void net_tx_action(struct softirq_action *h)
L
Linus Torvalds 已提交
3787
{
3788
	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
L
Linus Torvalds 已提交
3789 3790 3791 3792 3793 3794 3795 3796 3797 3798 3799 3800 3801

	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;

3802
			WARN_ON(atomic_read(&skb->users));
3803 3804 3805 3806
			if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
				trace_consume_skb(skb);
			else
				trace_kfree_skb(skb, net_tx_action);
3807 3808 3809 3810 3811

			if (skb->fclone != SKB_FCLONE_UNAVAILABLE)
				__kfree_skb(skb);
			else
				__kfree_skb_defer(skb);
L
Linus Torvalds 已提交
3812
		}
3813 3814

		__kfree_skb_flush();
L
Linus Torvalds 已提交
3815 3816 3817
	}

	if (sd->output_queue) {
3818
		struct Qdisc *head;
L
Linus Torvalds 已提交
3819 3820 3821 3822

		local_irq_disable();
		head = sd->output_queue;
		sd->output_queue = NULL;
3823
		sd->output_queue_tailp = &sd->output_queue;
L
Linus Torvalds 已提交
3824 3825 3826
		local_irq_enable();

		while (head) {
3827 3828 3829
			struct Qdisc *q = head;
			spinlock_t *root_lock;

L
Linus Torvalds 已提交
3830 3831
			head = head->next_sched;

3832
			root_lock = qdisc_lock(q);
3833 3834 3835 3836 3837 3838 3839 3840
			spin_lock(root_lock);
			/* We need to make sure head->next_sched is read
			 * before clearing __QDISC_STATE_SCHED
			 */
			smp_mb__before_atomic();
			clear_bit(__QDISC_STATE_SCHED, &q->state);
			qdisc_run(q);
			spin_unlock(root_lock);
L
Linus Torvalds 已提交
3841 3842 3843 3844
		}
	}
}

3845
#if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE)
3846 3847 3848
/* This hook is defined here for ATM LANE */
int (*br_fdb_test_addr_hook)(struct net_device *dev,
			     unsigned char *addr) __read_mostly;
3849
EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3850
#endif
L
Linus Torvalds 已提交
3851

D
Daniel Borkmann 已提交
3852 3853 3854
static inline struct sk_buff *
sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret,
		   struct net_device *orig_dev)
3855
{
3856
#ifdef CONFIG_NET_CLS_ACT
3857 3858
	struct tcf_proto *cl = rcu_dereference_bh(skb->dev->ingress_cl_list);
	struct tcf_result cl_res;
3859

3860 3861 3862
	/* If there's at least one ingress present somewhere (so
	 * we get here via enabled static key), remaining devices
	 * that are not configured with an ingress qdisc will bail
3863
	 * out here.
3864
	 */
3865
	if (!cl)
3866
		return skb;
3867 3868 3869
	if (*pt_prev) {
		*ret = deliver_skb(skb, *pt_prev, orig_dev);
		*pt_prev = NULL;
L
Linus Torvalds 已提交
3870 3871
	}

3872
	qdisc_skb_cb(skb)->pkt_len = skb->len;
3873
	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
3874
	qdisc_bstats_cpu_update(cl->q, skb);
3875

3876
	switch (tc_classify(skb, cl, &cl_res, false)) {
3877 3878 3879 3880 3881
	case TC_ACT_OK:
	case TC_ACT_RECLASSIFY:
		skb->tc_index = TC_H_MIN(cl_res.classid);
		break;
	case TC_ACT_SHOT:
3882
		qdisc_qstats_cpu_drop(cl->q);
3883 3884
		kfree_skb(skb);
		return NULL;
3885 3886
	case TC_ACT_STOLEN:
	case TC_ACT_QUEUED:
3887
		consume_skb(skb);
3888
		return NULL;
3889 3890 3891 3892 3893 3894 3895 3896
	case TC_ACT_REDIRECT:
		/* skb_mac_header check was done by cls/act_bpf, so
		 * we can safely push the L2 header back before
		 * redirecting to another netdev
		 */
		__skb_push(skb, skb->mac_len);
		skb_do_redirect(skb);
		return NULL;
3897 3898
	default:
		break;
3899
	}
3900
#endif /* CONFIG_NET_CLS_ACT */
3901 3902
	return skb;
}
L
Linus Torvalds 已提交
3903

M
Mahesh Bandewar 已提交
3904 3905 3906 3907 3908 3909 3910 3911 3912 3913 3914 3915 3916 3917 3918 3919
/**
 *	netdev_is_rx_handler_busy - check if receive handler is registered
 *	@dev: device to check
 *
 *	Check if a receive handler is already registered for a given device.
 *	Return true if there one.
 *
 *	The caller must hold the rtnl_mutex.
 */
bool netdev_is_rx_handler_busy(struct net_device *dev)
{
	ASSERT_RTNL();
	return dev && rtnl_dereference(dev->rx_handler);
}
EXPORT_SYMBOL_GPL(netdev_is_rx_handler_busy);

3920 3921 3922 3923
/**
 *	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
3924
 *	@rx_handler_data: data pointer that is used by rx handler
3925
 *
3926
 *	Register a receive handler for a device. This handler will then be
3927 3928 3929 3930
 *	called from __netif_receive_skb. A negative errno code is returned
 *	on a failure.
 *
 *	The caller must hold the rtnl_mutex.
3931 3932
 *
 *	For a general description of rx_handler, see enum rx_handler_result.
3933 3934
 */
int netdev_rx_handler_register(struct net_device *dev,
J
Jiri Pirko 已提交
3935 3936
			       rx_handler_func_t *rx_handler,
			       void *rx_handler_data)
3937 3938 3939 3940 3941 3942
{
	ASSERT_RTNL();

	if (dev->rx_handler)
		return -EBUSY;

3943
	/* Note: rx_handler_data must be set before rx_handler */
J
Jiri Pirko 已提交
3944
	rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3945 3946 3947 3948 3949 3950 3951 3952 3953 3954
	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
3955
 *	Unregister a receive handler from a device.
3956 3957 3958 3959 3960 3961 3962
 *
 *	The caller must hold the rtnl_mutex.
 */
void netdev_rx_handler_unregister(struct net_device *dev)
{

	ASSERT_RTNL();
3963
	RCU_INIT_POINTER(dev->rx_handler, NULL);
3964 3965 3966 3967 3968
	/* 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();
3969
	RCU_INIT_POINTER(dev->rx_handler_data, NULL);
3970 3971 3972
}
EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);

3973 3974 3975 3976 3977 3978 3979
/*
 * 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) {
3980 3981 3982 3983 3984
	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):
3985 3986 3987 3988 3989 3990
		return true;
	default:
		return false;
	}
}

3991 3992 3993
static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev,
			     int *ret, struct net_device *orig_dev)
{
3994
#ifdef CONFIG_NETFILTER_INGRESS
3995
	if (nf_hook_ingress_active(skb)) {
3996 3997
		int ingress_retval;

3998 3999 4000 4001 4002
		if (*pt_prev) {
			*ret = deliver_skb(skb, *pt_prev, orig_dev);
			*pt_prev = NULL;
		}

4003 4004 4005 4006
		rcu_read_lock();
		ingress_retval = nf_hook_ingress(skb);
		rcu_read_unlock();
		return ingress_retval;
4007
	}
4008
#endif /* CONFIG_NETFILTER_INGRESS */
4009 4010 4011
	return 0;
}

4012
static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
L
Linus Torvalds 已提交
4013 4014
{
	struct packet_type *ptype, *pt_prev;
4015
	rx_handler_func_t *rx_handler;
D
David S. Miller 已提交
4016
	struct net_device *orig_dev;
4017
	bool deliver_exact = false;
L
Linus Torvalds 已提交
4018
	int ret = NET_RX_DROP;
A
Al Viro 已提交
4019
	__be16 type;
L
Linus Torvalds 已提交
4020

4021
	net_timestamp_check(!netdev_tstamp_prequeue, skb);
4022

4023
	trace_netif_receive_skb(skb);
4024

J
Joe Eykholt 已提交
4025
	orig_dev = skb->dev;
4026

4027
	skb_reset_network_header(skb);
4028 4029
	if (!skb_transport_header_was_set(skb))
		skb_reset_transport_header(skb);
4030
	skb_reset_mac_len(skb);
L
Linus Torvalds 已提交
4031 4032 4033

	pt_prev = NULL;

4034
another_round:
4035
	skb->skb_iif = skb->dev->ifindex;
4036 4037 4038

	__this_cpu_inc(softnet_data.processed);

P
Patrick McHardy 已提交
4039 4040
	if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
	    skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
4041
		skb = skb_vlan_untag(skb);
4042
		if (unlikely(!skb))
4043
			goto out;
4044 4045
	}

L
Linus Torvalds 已提交
4046 4047 4048 4049 4050 4051 4052
#ifdef CONFIG_NET_CLS_ACT
	if (skb->tc_verd & TC_NCLS) {
		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
		goto ncls;
	}
#endif

4053
	if (pfmemalloc)
4054 4055
		goto skip_taps;

L
Linus Torvalds 已提交
4056
	list_for_each_entry_rcu(ptype, &ptype_all, list) {
4057 4058 4059 4060 4061 4062 4063 4064 4065
		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
4066 4067
	}

4068
skip_taps:
4069
#ifdef CONFIG_NET_INGRESS
4070
	if (static_key_false(&ingress_needed)) {
D
Daniel Borkmann 已提交
4071
		skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev);
4072
		if (!skb)
4073
			goto out;
4074 4075

		if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0)
4076
			goto out;
4077
	}
4078 4079
#endif
#ifdef CONFIG_NET_CLS_ACT
4080
	skb->tc_verd = 0;
L
Linus Torvalds 已提交
4081 4082
ncls:
#endif
4083
	if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
4084 4085
		goto drop;

4086
	if (skb_vlan_tag_present(skb)) {
4087 4088 4089 4090
		if (pt_prev) {
			ret = deliver_skb(skb, pt_prev, orig_dev);
			pt_prev = NULL;
		}
4091
		if (vlan_do_receive(&skb))
4092 4093
			goto another_round;
		else if (unlikely(!skb))
4094
			goto out;
4095 4096
	}

4097
	rx_handler = rcu_dereference(skb->dev->rx_handler);
4098 4099 4100 4101 4102
	if (rx_handler) {
		if (pt_prev) {
			ret = deliver_skb(skb, pt_prev, orig_dev);
			pt_prev = NULL;
		}
4103 4104
		switch (rx_handler(&skb)) {
		case RX_HANDLER_CONSUMED:
4105
			ret = NET_RX_SUCCESS;
4106
			goto out;
4107
		case RX_HANDLER_ANOTHER:
4108
			goto another_round;
4109 4110 4111 4112 4113 4114 4115
		case RX_HANDLER_EXACT:
			deliver_exact = true;
		case RX_HANDLER_PASS:
			break;
		default:
			BUG();
		}
4116
	}
L
Linus Torvalds 已提交
4117

4118 4119
	if (unlikely(skb_vlan_tag_present(skb))) {
		if (skb_vlan_tag_get_id(skb))
E
Eric Dumazet 已提交
4120 4121 4122 4123 4124 4125 4126
			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;
	}
4127

4128 4129
	type = skb->protocol;

4130
	/* deliver only exact match when indicated */
4131 4132 4133 4134 4135
	if (likely(!deliver_exact)) {
		deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
				       &ptype_base[ntohs(type) &
						   PTYPE_HASH_MASK]);
	}
4136

4137 4138 4139 4140 4141 4142
	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
4143 4144 4145
	}

	if (pt_prev) {
4146
		if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
4147
			goto drop;
4148 4149
		else
			ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
L
Linus Torvalds 已提交
4150
	} else {
4151
drop:
4152 4153 4154 4155
		if (!deliver_exact)
			atomic_long_inc(&skb->dev->rx_dropped);
		else
			atomic_long_inc(&skb->dev->rx_nohandler);
L
Linus Torvalds 已提交
4156 4157 4158 4159 4160 4161 4162
		kfree_skb(skb);
		/* Jamal, now you will not able to escape explaining
		 * me how you were going to use this. :-)
		 */
		ret = NET_RX_DROP;
	}

4163
out:
4164 4165 4166 4167 4168 4169 4170 4171 4172 4173 4174 4175 4176 4177 4178 4179 4180 4181 4182 4183 4184 4185 4186 4187 4188
	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
4189 4190
	return ret;
}
T
Tom Herbert 已提交
4191

4192
static int netif_receive_skb_internal(struct sk_buff *skb)
T
Tom Herbert 已提交
4193
{
4194 4195
	int ret;

4196
	net_timestamp_check(netdev_tstamp_prequeue, skb);
E
Eric Dumazet 已提交
4197

4198 4199 4200
	if (skb_defer_rx_timestamp(skb))
		return NET_RX_SUCCESS;

4201 4202
	rcu_read_lock();

E
Eric Dumazet 已提交
4203
#ifdef CONFIG_RPS
4204
	if (static_key_false(&rps_needed)) {
E
Eric Dumazet 已提交
4205
		struct rps_dev_flow voidflow, *rflow = &voidflow;
4206
		int cpu = get_rps_cpu(skb->dev, skb, &rflow);
T
Tom Herbert 已提交
4207

E
Eric Dumazet 已提交
4208 4209 4210
		if (cpu >= 0) {
			ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
			rcu_read_unlock();
4211
			return ret;
E
Eric Dumazet 已提交
4212
		}
T
Tom Herbert 已提交
4213
	}
4214
#endif
4215 4216 4217
	ret = __netif_receive_skb(skb);
	rcu_read_unlock();
	return ret;
T
Tom Herbert 已提交
4218
}
4219 4220 4221 4222 4223 4224 4225 4226 4227 4228 4229 4230 4231 4232 4233 4234

/**
 *	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
 */
4235
int netif_receive_skb(struct sk_buff *skb)
4236 4237 4238 4239 4240
{
	trace_netif_receive_skb_entry(skb);

	return netif_receive_skb_internal(skb);
}
4241
EXPORT_SYMBOL(netif_receive_skb);
L
Linus Torvalds 已提交
4242

4243
DEFINE_PER_CPU(struct work_struct, flush_works);
4244 4245 4246

/* Network device is going away, flush any packets still pending */
static void flush_backlog(struct work_struct *work)
4247 4248
{
	struct sk_buff *skb, *tmp;
4249 4250 4251 4252
	struct softnet_data *sd;

	local_bh_disable();
	sd = this_cpu_ptr(&softnet_data);
4253

4254
	local_irq_disable();
E
Eric Dumazet 已提交
4255
	rps_lock(sd);
4256
	skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
4257
		if (skb->dev->reg_state == NETREG_UNREGISTERING) {
E
Eric Dumazet 已提交
4258
			__skb_unlink(skb, &sd->input_pkt_queue);
4259
			kfree_skb(skb);
4260
			input_queue_head_incr(sd);
4261
		}
4262
	}
E
Eric Dumazet 已提交
4263
	rps_unlock(sd);
4264
	local_irq_enable();
4265 4266

	skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
4267
		if (skb->dev->reg_state == NETREG_UNREGISTERING) {
4268 4269
			__skb_unlink(skb, &sd->process_queue);
			kfree_skb(skb);
4270
			input_queue_head_incr(sd);
4271 4272
		}
	}
4273 4274 4275
	local_bh_enable();
}

4276
static void flush_all_backlogs(void)
4277 4278 4279 4280 4281
{
	unsigned int cpu;

	get_online_cpus();

4282 4283 4284
	for_each_online_cpu(cpu)
		queue_work_on(cpu, system_highpri_wq,
			      per_cpu_ptr(&flush_works, cpu));
4285 4286

	for_each_online_cpu(cpu)
4287
		flush_work(per_cpu_ptr(&flush_works, cpu));
4288 4289

	put_online_cpus();
4290 4291
}

4292 4293
static int napi_gro_complete(struct sk_buff *skb)
{
4294
	struct packet_offload *ptype;
4295
	__be16 type = skb->protocol;
4296
	struct list_head *head = &offload_base;
4297 4298
	int err = -ENOENT;

4299 4300
	BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));

4301 4302
	if (NAPI_GRO_CB(skb)->count == 1) {
		skb_shinfo(skb)->gso_size = 0;
4303
		goto out;
4304
	}
4305 4306 4307

	rcu_read_lock();
	list_for_each_entry_rcu(ptype, head, list) {
4308
		if (ptype->type != type || !ptype->callbacks.gro_complete)
4309 4310
			continue;

4311
		err = ptype->callbacks.gro_complete(skb, 0);
4312 4313 4314 4315 4316 4317 4318 4319 4320 4321 4322
		break;
	}
	rcu_read_unlock();

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

out:
4323
	return netif_receive_skb_internal(skb);
4324 4325
}

4326 4327 4328 4329 4330
/* 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)
4331
{
4332
	struct sk_buff *skb, *prev = NULL;
4333

4334 4335 4336 4337 4338 4339 4340
	/* 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) {
4341
		skb->next = NULL;
4342 4343 4344 4345 4346

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

		prev = skb->prev;
4347
		napi_gro_complete(skb);
4348
		napi->gro_count--;
4349 4350 4351 4352
	}

	napi->gro_list = NULL;
}
E
Eric Dumazet 已提交
4353
EXPORT_SYMBOL(napi_gro_flush);
4354

E
Eric Dumazet 已提交
4355 4356 4357 4358
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;
4359
	u32 hash = skb_get_hash_raw(skb);
E
Eric Dumazet 已提交
4360 4361 4362 4363

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

4364 4365 4366 4367 4368 4369 4370
		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
4371 4372
		diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
		diffs |= p->vlan_tci ^ skb->vlan_tci;
4373
		diffs |= skb_metadata_dst_cmp(p, skb);
E
Eric Dumazet 已提交
4374 4375
		if (maclen == ETH_HLEN)
			diffs |= compare_ether_header(skb_mac_header(p),
4376
						      skb_mac_header(skb));
E
Eric Dumazet 已提交
4377 4378
		else if (!diffs)
			diffs = memcmp(skb_mac_header(p),
4379
				       skb_mac_header(skb),
E
Eric Dumazet 已提交
4380 4381 4382 4383 4384
				       maclen);
		NAPI_GRO_CB(p)->same_flow = !diffs;
	}
}

4385 4386 4387 4388 4389 4390 4391 4392 4393 4394 4395 4396 4397 4398
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
4399 4400 4401
	}
}

4402 4403 4404 4405 4406 4407 4408 4409 4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421 4422
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
4423
static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4424 4425
{
	struct sk_buff **pp = NULL;
4426
	struct packet_offload *ptype;
4427
	__be16 type = skb->protocol;
4428
	struct list_head *head = &offload_base;
H
Herbert Xu 已提交
4429
	int same_flow;
4430
	enum gro_result ret;
4431
	int grow;
4432

4433
	if (!(skb->dev->features & NETIF_F_GRO))
4434 4435
		goto normal;

4436
	if (skb_is_gso(skb) || skb_has_frag_list(skb) || skb->csum_bad)
4437 4438
		goto normal;

E
Eric Dumazet 已提交
4439 4440
	gro_list_prepare(napi, skb);

4441 4442
	rcu_read_lock();
	list_for_each_entry_rcu(ptype, head, list) {
4443
		if (ptype->type != type || !ptype->callbacks.gro_receive)
4444 4445
			continue;

4446
		skb_set_network_header(skb, skb_gro_offset(skb));
4447
		skb_reset_mac_len(skb);
4448 4449
		NAPI_GRO_CB(skb)->same_flow = 0;
		NAPI_GRO_CB(skb)->flush = 0;
H
Herbert Xu 已提交
4450
		NAPI_GRO_CB(skb)->free = 0;
4451
		NAPI_GRO_CB(skb)->encap_mark = 0;
S
Sabrina Dubroca 已提交
4452
		NAPI_GRO_CB(skb)->recursion_counter = 0;
4453
		NAPI_GRO_CB(skb)->is_fou = 0;
4454
		NAPI_GRO_CB(skb)->is_atomic = 1;
4455
		NAPI_GRO_CB(skb)->gro_remcsum_start = 0;
4456

4457 4458 4459 4460 4461 4462 4463 4464 4465 4466 4467 4468 4469 4470 4471
		/* 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;
		}
4472

4473
		pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
4474 4475 4476 4477 4478 4479 4480
		break;
	}
	rcu_read_unlock();

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

H
Herbert Xu 已提交
4481
	same_flow = NAPI_GRO_CB(skb)->same_flow;
4482
	ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
H
Herbert Xu 已提交
4483

4484 4485 4486 4487 4488 4489
	if (pp) {
		struct sk_buff *nskb = *pp;

		*pp = nskb->next;
		nskb->next = NULL;
		napi_gro_complete(nskb);
4490
		napi->gro_count--;
4491 4492
	}

H
Herbert Xu 已提交
4493
	if (same_flow)
4494 4495
		goto ok;

4496
	if (NAPI_GRO_CB(skb)->flush)
4497 4498
		goto normal;

4499 4500 4501 4502 4503 4504 4505 4506 4507 4508 4509 4510 4511 4512
	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++;
	}
4513
	NAPI_GRO_CB(skb)->count = 1;
4514
	NAPI_GRO_CB(skb)->age = jiffies;
4515
	NAPI_GRO_CB(skb)->last = skb;
4516
	skb_shinfo(skb)->gso_size = skb_gro_len(skb);
4517 4518
	skb->next = napi->gro_list;
	napi->gro_list = skb;
4519
	ret = GRO_HELD;
4520

4521
pull:
4522 4523 4524
	grow = skb_gro_offset(skb) - skb_headlen(skb);
	if (grow > 0)
		gro_pull_from_frag0(skb, grow);
4525
ok:
4526
	return ret;
4527 4528

normal:
4529 4530
	ret = GRO_NORMAL;
	goto pull;
H
Herbert Xu 已提交
4531
}
4532

4533 4534 4535 4536 4537 4538 4539 4540 4541 4542 4543 4544
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;
}
4545
EXPORT_SYMBOL(gro_find_receive_by_type);
4546 4547 4548 4549 4550 4551 4552 4553 4554 4555 4556 4557 4558

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;
}
4559
EXPORT_SYMBOL(gro_find_complete_by_type);
H
Herbert Xu 已提交
4560

R
Rami Rosen 已提交
4561
static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
H
Herbert Xu 已提交
4562
{
4563 4564
	switch (ret) {
	case GRO_NORMAL:
4565
		if (netif_receive_skb_internal(skb))
4566 4567
			ret = GRO_DROP;
		break;
H
Herbert Xu 已提交
4568

4569
	case GRO_DROP:
H
Herbert Xu 已提交
4570 4571
		kfree_skb(skb);
		break;
4572

4573
	case GRO_MERGED_FREE:
4574 4575
		if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD) {
			skb_dst_drop(skb);
4576
			kmem_cache_free(skbuff_head_cache, skb);
4577
		} else {
4578
			__kfree_skb(skb);
4579
		}
4580 4581
		break;

4582 4583 4584
	case GRO_HELD:
	case GRO_MERGED:
		break;
H
Herbert Xu 已提交
4585 4586
	}

4587
	return ret;
4588 4589
}

4590
gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4591
{
4592
	skb_mark_napi_id(skb, napi);
4593
	trace_napi_gro_receive_entry(skb);
4594

4595 4596
	skb_gro_reset_offset(skb);

E
Eric Dumazet 已提交
4597
	return napi_skb_finish(dev_gro_receive(napi, skb), skb);
4598 4599 4600
}
EXPORT_SYMBOL(napi_gro_receive);

S
stephen hemminger 已提交
4601
static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
4602
{
4603 4604 4605 4606
	if (unlikely(skb->pfmemalloc)) {
		consume_skb(skb);
		return;
	}
4607
	__skb_pull(skb, skb_headlen(skb));
4608 4609
	/* restore the reserve we had after netdev_alloc_skb_ip_align() */
	skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
4610
	skb->vlan_tci = 0;
H
Herbert Xu 已提交
4611
	skb->dev = napi->dev;
A
Andy Gospodarek 已提交
4612
	skb->skb_iif = 0;
4613 4614
	skb->encapsulation = 0;
	skb_shinfo(skb)->gso_type = 0;
4615
	skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
4616 4617 4618 4619

	napi->skb = skb;
}

4620
struct sk_buff *napi_get_frags(struct napi_struct *napi)
H
Herbert Xu 已提交
4621 4622 4623 4624
{
	struct sk_buff *skb = napi->skb;

	if (!skb) {
4625
		skb = napi_alloc_skb(napi, GRO_MAX_HEAD);
4626 4627 4628 4629
		if (skb) {
			napi->skb = skb;
			skb_mark_napi_id(skb, napi);
		}
4630
	}
4631 4632
	return skb;
}
4633
EXPORT_SYMBOL(napi_get_frags);
4634

4635 4636 4637
static gro_result_t napi_frags_finish(struct napi_struct *napi,
				      struct sk_buff *skb,
				      gro_result_t ret)
4638
{
4639 4640
	switch (ret) {
	case GRO_NORMAL:
4641 4642 4643 4644
	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))
4645
			ret = GRO_DROP;
4646
		break;
H
Herbert Xu 已提交
4647

4648 4649 4650 4651
	case GRO_DROP:
	case GRO_MERGED_FREE:
		napi_reuse_skb(napi, skb);
		break;
4652 4653 4654

	case GRO_MERGED:
		break;
4655
	}
H
Herbert Xu 已提交
4656

4657
	return ret;
H
Herbert Xu 已提交
4658
}
4659

4660 4661 4662 4663
/* 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
4664
static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4665 4666
{
	struct sk_buff *skb = napi->skb;
4667 4668
	const struct ethhdr *eth;
	unsigned int hlen = sizeof(*eth);
4669 4670 4671

	napi->skb = NULL;

4672 4673 4674 4675 4676 4677 4678
	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)) {
4679 4680
			net_warn_ratelimited("%s: dropping impossible skb from %s\n",
					     __func__, napi->dev->name);
4681 4682 4683 4684 4685 4686 4687
			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;
4688
	}
4689 4690 4691 4692 4693 4694 4695 4696
	__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;
4697 4698 4699 4700

	return skb;
}

4701
gro_result_t napi_gro_frags(struct napi_struct *napi)
4702
{
4703
	struct sk_buff *skb = napi_frags_skb(napi);
4704 4705

	if (!skb)
4706
		return GRO_DROP;
4707

4708 4709
	trace_napi_gro_frags_entry(skb);

E
Eric Dumazet 已提交
4710
	return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4711
}
H
Herbert Xu 已提交
4712 4713
EXPORT_SYMBOL(napi_gro_frags);

T
Tom Herbert 已提交
4714 4715 4716 4717 4718 4719 4720 4721 4722 4723 4724 4725 4726 4727 4728 4729 4730 4731 4732 4733 4734 4735 4736 4737 4738
/* 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);

4739
/*
4740
 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
4741 4742 4743 4744 4745 4746 4747 4748 4749 4750 4751 4752 4753 4754 4755 4756 4757
 * 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))
4758
				smp_call_function_single_async(remsd->cpu,
4759
							   &remsd->csd);
4760 4761 4762 4763 4764 4765 4766
			remsd = next;
		}
	} else
#endif
		local_irq_enable();
}

E
Eric Dumazet 已提交
4767 4768 4769 4770 4771 4772 4773 4774 4775
static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
{
#ifdef CONFIG_RPS
	return sd->rps_ipi_list != NULL;
#else
	return false;
#endif
}

4776
static int process_backlog(struct napi_struct *napi, int quota)
L
Linus Torvalds 已提交
4777
{
E
Eric Dumazet 已提交
4778
	struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
4779 4780
	bool again = true;
	int work = 0;
L
Linus Torvalds 已提交
4781

4782 4783 4784
	/* Check if we have pending ipi, its better to send them now,
	 * not waiting net_rx_action() end.
	 */
E
Eric Dumazet 已提交
4785
	if (sd_has_rps_ipi_waiting(sd)) {
4786 4787 4788
		local_irq_disable();
		net_rps_action_and_irq_enable(sd);
	}
E
Eric Dumazet 已提交
4789

4790
	napi->weight = weight_p;
4791
	while (again) {
L
Linus Torvalds 已提交
4792
		struct sk_buff *skb;
4793 4794

		while ((skb = __skb_dequeue(&sd->process_queue))) {
4795
			rcu_read_lock();
4796
			__netif_receive_skb(skb);
4797
			rcu_read_unlock();
4798
			input_queue_head_incr(sd);
4799
			if (++work >= quota)
4800
				return work;
4801

4802
		}
L
Linus Torvalds 已提交
4803

4804
		local_irq_disable();
E
Eric Dumazet 已提交
4805
		rps_lock(sd);
4806
		if (skb_queue_empty(&sd->input_pkt_queue)) {
E
Eric Dumazet 已提交
4807 4808 4809
			/*
			 * Inline a custom version of __napi_complete().
			 * only current cpu owns and manipulates this napi,
4810 4811 4812
			 * 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
4813 4814 4815
			 * and we dont need an smp_mb() memory barrier.
			 */
			napi->state = 0;
4816 4817 4818 4819
			again = false;
		} else {
			skb_queue_splice_tail_init(&sd->input_pkt_queue,
						   &sd->process_queue);
4820
		}
E
Eric Dumazet 已提交
4821
		rps_unlock(sd);
4822
		local_irq_enable();
4823
	}
L
Linus Torvalds 已提交
4824

4825 4826
	return work;
}
L
Linus Torvalds 已提交
4827

4828 4829
/**
 * __napi_schedule - schedule for receive
4830
 * @n: entry to schedule
4831
 *
4832 4833
 * The entry's receive function will be scheduled to run.
 * Consider using __napi_schedule_irqoff() if hard irqs are masked.
4834
 */
H
Harvey Harrison 已提交
4835
void __napi_schedule(struct napi_struct *n)
4836 4837
{
	unsigned long flags;
L
Linus Torvalds 已提交
4838

4839
	local_irq_save(flags);
4840
	____napi_schedule(this_cpu_ptr(&softnet_data), n);
4841
	local_irq_restore(flags);
L
Linus Torvalds 已提交
4842
}
4843 4844
EXPORT_SYMBOL(__napi_schedule);

4845 4846 4847 4848 4849 4850 4851 4852 4853 4854 4855 4856
/**
 * __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);

4857 4858 4859 4860
void __napi_complete(struct napi_struct *n)
{
	BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));

E
Eric Dumazet 已提交
4861
	list_del_init(&n->poll_list);
4862
	smp_mb__before_atomic();
4863 4864 4865 4866
	clear_bit(NAPI_STATE_SCHED, &n->state);
}
EXPORT_SYMBOL(__napi_complete);

4867
void napi_complete_done(struct napi_struct *n, int work_done)
4868 4869 4870 4871 4872 4873 4874 4875 4876 4877
{
	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;

4878 4879
	if (n->gro_list) {
		unsigned long timeout = 0;
E
Eric Dumazet 已提交
4880

4881 4882 4883 4884 4885 4886 4887 4888 4889
		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
4890 4891 4892 4893 4894 4895 4896 4897
	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);
	}
4898
}
4899
EXPORT_SYMBOL(napi_complete_done);
4900

E
Eliezer Tamir 已提交
4901
/* must be called under rcu_read_lock(), as we dont take a reference */
E
Eric Dumazet 已提交
4902
static struct napi_struct *napi_by_id(unsigned int napi_id)
E
Eliezer Tamir 已提交
4903 4904 4905 4906 4907 4908 4909 4910 4911 4912
{
	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;
}
E
Eric Dumazet 已提交
4913 4914

#if defined(CONFIG_NET_RX_BUSY_POLL)
4915
#define BUSY_POLL_BUDGET 8
E
Eric Dumazet 已提交
4916 4917 4918
bool sk_busy_loop(struct sock *sk, int nonblock)
{
	unsigned long end_time = !nonblock ? sk_busy_loop_end_time(sk) : 0;
4919
	int (*busy_poll)(struct napi_struct *dev);
E
Eric Dumazet 已提交
4920 4921 4922
	struct napi_struct *napi;
	int rc = false;

4923
	rcu_read_lock();
E
Eric Dumazet 已提交
4924 4925 4926 4927 4928

	napi = napi_by_id(sk->sk_napi_id);
	if (!napi)
		goto out;

4929 4930
	/* Note: ndo_busy_poll method is optional in linux-4.5 */
	busy_poll = napi->dev->netdev_ops->ndo_busy_poll;
E
Eric Dumazet 已提交
4931 4932

	do {
4933
		rc = 0;
4934
		local_bh_disable();
4935 4936 4937 4938 4939 4940 4941
		if (busy_poll) {
			rc = busy_poll(napi);
		} else if (napi_schedule_prep(napi)) {
			void *have = netpoll_poll_lock(napi);

			if (test_bit(NAPI_STATE_SCHED, &napi->state)) {
				rc = napi->poll(napi, BUSY_POLL_BUDGET);
4942
				trace_napi_poll(napi, rc, BUSY_POLL_BUDGET);
4943 4944 4945 4946 4947 4948 4949
				if (rc == BUSY_POLL_BUDGET) {
					napi_complete_done(napi, rc);
					napi_schedule(napi);
				}
			}
			netpoll_poll_unlock(have);
		}
4950
		if (rc > 0)
4951 4952
			__NET_ADD_STATS(sock_net(sk),
					LINUX_MIB_BUSYPOLLRXPACKETS, rc);
4953
		local_bh_enable();
E
Eric Dumazet 已提交
4954 4955 4956 4957 4958 4959 4960 4961 4962 4963

		if (rc == LL_FLUSH_FAILED)
			break; /* permanent failure */

		cpu_relax();
	} while (!nonblock && skb_queue_empty(&sk->sk_receive_queue) &&
		 !need_resched() && !busy_loop_timeout(end_time));

	rc = !skb_queue_empty(&sk->sk_receive_queue);
out:
4964
	rcu_read_unlock();
E
Eric Dumazet 已提交
4965 4966 4967 4968 4969
	return rc;
}
EXPORT_SYMBOL(sk_busy_loop);

#endif /* CONFIG_NET_RX_BUSY_POLL */
E
Eliezer Tamir 已提交
4970 4971 4972

void napi_hash_add(struct napi_struct *napi)
{
E
Eric Dumazet 已提交
4973 4974
	if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state) ||
	    test_and_set_bit(NAPI_STATE_HASHED, &napi->state))
4975
		return;
E
Eliezer Tamir 已提交
4976

4977
	spin_lock(&napi_hash_lock);
E
Eliezer Tamir 已提交
4978

4979 4980 4981 4982 4983 4984
	/* 0..NR_CPUS+1 range is reserved for sender_cpu use */
	do {
		if (unlikely(++napi_gen_id < NR_CPUS + 1))
			napi_gen_id = NR_CPUS + 1;
	} while (napi_by_id(napi_gen_id));
	napi->napi_id = napi_gen_id;
E
Eliezer Tamir 已提交
4985

4986 4987
	hlist_add_head_rcu(&napi->napi_hash_node,
			   &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
E
Eliezer Tamir 已提交
4988

4989
	spin_unlock(&napi_hash_lock);
E
Eliezer Tamir 已提交
4990 4991 4992 4993 4994 4995
}
EXPORT_SYMBOL_GPL(napi_hash_add);

/* Warning : caller is responsible to make sure rcu grace period
 * is respected before freeing memory containing @napi
 */
4996
bool napi_hash_del(struct napi_struct *napi)
E
Eliezer Tamir 已提交
4997
{
4998 4999
	bool rcu_sync_needed = false;

E
Eliezer Tamir 已提交
5000 5001
	spin_lock(&napi_hash_lock);

5002 5003
	if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state)) {
		rcu_sync_needed = true;
E
Eliezer Tamir 已提交
5004
		hlist_del_rcu(&napi->napi_hash_node);
5005
	}
E
Eliezer Tamir 已提交
5006
	spin_unlock(&napi_hash_lock);
5007
	return rcu_sync_needed;
E
Eliezer Tamir 已提交
5008 5009 5010
}
EXPORT_SYMBOL_GPL(napi_hash_del);

5011 5012 5013 5014 5015 5016 5017 5018 5019 5020 5021
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;
}

5022 5023 5024 5025
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);
5026 5027
	hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED);
	napi->timer.function = napi_watchdog;
5028
	napi->gro_count = 0;
5029
	napi->gro_list = NULL;
H
Herbert Xu 已提交
5030
	napi->skb = NULL;
5031
	napi->poll = poll;
E
Eric Dumazet 已提交
5032 5033 5034
	if (weight > NAPI_POLL_WEIGHT)
		pr_err_once("netif_napi_add() called with weight %d on device %s\n",
			    weight, dev->name);
5035 5036 5037
	napi->weight = weight;
	list_add(&napi->dev_list, &dev->napi_list);
	napi->dev = dev;
H
Herbert Xu 已提交
5038
#ifdef CONFIG_NETPOLL
5039 5040 5041 5042
	spin_lock_init(&napi->poll_lock);
	napi->poll_owner = -1;
#endif
	set_bit(NAPI_STATE_SCHED, &napi->state);
5043
	napi_hash_add(napi);
5044 5045 5046
}
EXPORT_SYMBOL(netif_napi_add);

5047 5048 5049 5050 5051 5052 5053
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);
5054 5055
	while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state))
		msleep(1);
5056 5057 5058 5059 5060 5061 5062

	hrtimer_cancel(&n->timer);

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

5063
/* Must be called in process context */
5064 5065
void netif_napi_del(struct napi_struct *napi)
{
5066 5067 5068
	might_sleep();
	if (napi_hash_del(napi))
		synchronize_net();
5069
	list_del_init(&napi->dev_list);
5070
	napi_free_frags(napi);
5071

E
Eric Dumazet 已提交
5072
	kfree_skb_list(napi->gro_list);
5073
	napi->gro_list = NULL;
5074
	napi->gro_count = 0;
5075 5076 5077
}
EXPORT_SYMBOL(netif_napi_del);

5078 5079 5080 5081 5082 5083 5084 5085 5086 5087 5088 5089 5090 5091 5092 5093 5094 5095 5096 5097
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);
5098
		trace_napi_poll(n, work, weight);
5099 5100 5101 5102 5103 5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122
	}

	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);
	}

5123 5124 5125 5126 5127 5128 5129 5130 5131
	/* 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;
	}

5132 5133 5134 5135 5136 5137 5138 5139
	list_add_tail(&n->poll_list, repoll);

out_unlock:
	netpoll_poll_unlock(have);

	return work;
}

5140
static __latent_entropy void net_rx_action(struct softirq_action *h)
L
Linus Torvalds 已提交
5141
{
5142
	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
5143
	unsigned long time_limit = jiffies + 2;
5144
	int budget = netdev_budget;
E
Eric Dumazet 已提交
5145 5146
	LIST_HEAD(list);
	LIST_HEAD(repoll);
5147

L
Linus Torvalds 已提交
5148
	local_irq_disable();
E
Eric Dumazet 已提交
5149 5150
	list_splice_init(&sd->poll_list, &list);
	local_irq_enable();
L
Linus Torvalds 已提交
5151

H
Herbert Xu 已提交
5152
	for (;;) {
5153
		struct napi_struct *n;
L
Linus Torvalds 已提交
5154

H
Herbert Xu 已提交
5155 5156 5157 5158 5159 5160
		if (list_empty(&list)) {
			if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll))
				return;
			break;
		}

5161 5162 5163
		n = list_first_entry(&list, struct napi_struct, poll_list);
		budget -= napi_poll(n, &repoll);

E
Eric Dumazet 已提交
5164
		/* If softirq window is exhausted then punt.
5165 5166
		 * Allow this to run for 2 jiffies since which will allow
		 * an average latency of 1.5/HZ.
5167
		 */
H
Herbert Xu 已提交
5168 5169 5170 5171 5172
		if (unlikely(budget <= 0 ||
			     time_after_eq(jiffies, time_limit))) {
			sd->time_squeeze++;
			break;
		}
L
Linus Torvalds 已提交
5173
	}
E
Eric Dumazet 已提交
5174

5175
	__kfree_skb_flush();
E
Eric Dumazet 已提交
5176 5177 5178 5179 5180 5181 5182 5183
	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);

5184
	net_rps_action_and_irq_enable(sd);
L
Linus Torvalds 已提交
5185 5186
}

5187
struct netdev_adjacent {
J
Jiri Pirko 已提交
5188
	struct net_device *dev;
5189 5190

	/* upper master flag, there can only be one master device per list */
J
Jiri Pirko 已提交
5191
	bool master;
5192 5193 5194 5195

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

5196 5197 5198
	/* private field for the users */
	void *private;

J
Jiri Pirko 已提交
5199 5200 5201 5202
	struct list_head list;
	struct rcu_head rcu;
};

5203
static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev,
5204
						 struct list_head *adj_list)
J
Jiri Pirko 已提交
5205
{
5206 5207
	struct netdev_adjacent *adj;

5208
	list_for_each_entry(adj, adj_list, list) {
5209 5210
		if (adj->dev == adj_dev)
			return adj;
J
Jiri Pirko 已提交
5211 5212 5213 5214
	}
	return NULL;
}

5215 5216 5217 5218 5219 5220 5221
static int __netdev_has_upper_dev(struct net_device *upper_dev, void *data)
{
	struct net_device *dev = data;

	return upper_dev == dev;
}

J
Jiri Pirko 已提交
5222 5223 5224 5225 5226 5227 5228 5229 5230 5231 5232 5233 5234 5235
/**
 * 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();

5236 5237
	return netdev_walk_all_upper_dev_rcu(dev, __netdev_has_upper_dev,
					     upper_dev);
J
Jiri Pirko 已提交
5238 5239 5240
}
EXPORT_SYMBOL(netdev_has_upper_dev);

5241 5242 5243 5244 5245 5246 5247 5248 5249 5250 5251 5252 5253 5254 5255 5256 5257 5258
/**
 * netdev_has_upper_dev_all - 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 the entire upper device chain.
 * The caller must hold rcu lock.
 */

bool netdev_has_upper_dev_all_rcu(struct net_device *dev,
				  struct net_device *upper_dev)
{
	return !!netdev_walk_all_upper_dev_rcu(dev, __netdev_has_upper_dev,
					       upper_dev);
}
EXPORT_SYMBOL(netdev_has_upper_dev_all_rcu);

J
Jiri Pirko 已提交
5259 5260 5261 5262 5263 5264 5265
/**
 * 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
5266
static bool netdev_has_any_upper_dev(struct net_device *dev)
J
Jiri Pirko 已提交
5267 5268 5269
{
	ASSERT_RTNL();

5270
	return !list_empty(&dev->adj_list.upper);
J
Jiri Pirko 已提交
5271 5272 5273 5274 5275 5276 5277 5278 5279 5280 5281
}

/**
 * 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)
{
5282
	struct netdev_adjacent *upper;
J
Jiri Pirko 已提交
5283 5284 5285

	ASSERT_RTNL();

5286
	if (list_empty(&dev->adj_list.upper))
J
Jiri Pirko 已提交
5287 5288
		return NULL;

5289
	upper = list_first_entry(&dev->adj_list.upper,
5290
				 struct netdev_adjacent, list);
J
Jiri Pirko 已提交
5291 5292 5293 5294 5295 5296
	if (likely(upper->master))
		return upper->dev;
	return NULL;
}
EXPORT_SYMBOL(netdev_master_upper_dev_get);

5297 5298 5299 5300 5301 5302 5303 5304 5305 5306 5307 5308 5309 5310
/**
 * netdev_has_any_lower_dev - Check if device is linked to some device
 * @dev: device
 *
 * Find out if a device is linked to a lower device and return true in case
 * it is. The caller must hold the RTNL lock.
 */
static bool netdev_has_any_lower_dev(struct net_device *dev)
{
	ASSERT_RTNL();

	return !list_empty(&dev->adj_list.lower);
}

5311 5312 5313 5314 5315 5316 5317 5318 5319 5320
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);

5321 5322 5323 5324 5325 5326 5327 5328 5329 5330 5331 5332 5333 5334 5335 5336 5337 5338 5339 5340 5341 5342 5343 5344 5345 5346
/**
 * 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);

5347 5348 5349 5350 5351 5352 5353 5354 5355 5356 5357 5358 5359 5360 5361 5362 5363 5364 5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376 5377 5378 5379 5380 5381 5382 5383 5384 5385 5386 5387 5388 5389 5390 5391
static struct net_device *netdev_next_upper_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;
}

int netdev_walk_all_upper_dev_rcu(struct net_device *dev,
				  int (*fn)(struct net_device *dev,
					    void *data),
				  void *data)
{
	struct net_device *udev;
	struct list_head *iter;
	int ret;

	for (iter = &dev->adj_list.upper,
	     udev = netdev_next_upper_dev_rcu(dev, &iter);
	     udev;
	     udev = netdev_next_upper_dev_rcu(dev, &iter)) {
		/* first is the upper device itself */
		ret = fn(udev, data);
		if (ret)
			return ret;

		/* then look at all of its upper devices */
		ret = netdev_walk_all_upper_dev_rcu(udev, fn, data);
		if (ret)
			return ret;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(netdev_walk_all_upper_dev_rcu);

5392 5393 5394 5395 5396 5397 5398 5399 5400
/**
 * 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
5401
 * list will remain unchanged.
5402 5403 5404 5405 5406 5407 5408 5409 5410 5411 5412
 */
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;

5413
	*iter = lower->list.next;
5414 5415 5416 5417 5418 5419 5420 5421 5422 5423 5424 5425 5426 5427 5428 5429 5430 5431 5432 5433 5434 5435 5436 5437 5438 5439 5440

	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;

5441
	*iter = &lower->list;
5442 5443 5444 5445 5446

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

5447 5448 5449 5450 5451 5452 5453 5454 5455
/**
 * 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
5456
 * list will remain unchanged.
5457 5458 5459 5460 5461
 */
void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
{
	struct netdev_adjacent *lower;

5462
	lower = list_entry(*iter, struct netdev_adjacent, list);
5463 5464 5465 5466

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

5467
	*iter = lower->list.next;
5468 5469 5470 5471 5472

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

5473 5474 5475 5476 5477
static struct net_device *netdev_next_lower_dev(struct net_device *dev,
						struct list_head **iter)
{
	struct netdev_adjacent *lower;

5478
	lower = list_entry((*iter)->next, struct netdev_adjacent, list);
5479 5480 5481 5482

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

5483
	*iter = &lower->list;
5484 5485 5486 5487 5488 5489 5490 5491 5492 5493 5494 5495 5496 5497 5498 5499 5500 5501 5502 5503 5504 5505 5506 5507 5508 5509 5510 5511 5512 5513 5514 5515 5516 5517 5518 5519 5520 5521 5522 5523 5524 5525 5526 5527 5528 5529 5530 5531 5532 5533 5534 5535 5536 5537 5538 5539 5540 5541 5542 5543 5544 5545 5546 5547 5548 5549 5550 5551 5552 5553 5554 5555 5556 5557

	return lower->dev;
}

int netdev_walk_all_lower_dev(struct net_device *dev,
			      int (*fn)(struct net_device *dev,
					void *data),
			      void *data)
{
	struct net_device *ldev;
	struct list_head *iter;
	int ret;

	for (iter = &dev->adj_list.lower,
	     ldev = netdev_next_lower_dev(dev, &iter);
	     ldev;
	     ldev = netdev_next_lower_dev(dev, &iter)) {
		/* first is the lower device itself */
		ret = fn(ldev, data);
		if (ret)
			return ret;

		/* then look at all of its lower devices */
		ret = netdev_walk_all_lower_dev(ldev, fn, data);
		if (ret)
			return ret;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev);

static struct net_device *netdev_next_lower_dev_rcu(struct net_device *dev,
						    struct list_head **iter)
{
	struct netdev_adjacent *lower;

	lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
	if (&lower->list == &dev->adj_list.lower)
		return NULL;

	*iter = &lower->list;

	return lower->dev;
}

int netdev_walk_all_lower_dev_rcu(struct net_device *dev,
				  int (*fn)(struct net_device *dev,
					    void *data),
				  void *data)
{
	struct net_device *ldev;
	struct list_head *iter;
	int ret;

	for (iter = &dev->adj_list.lower,
	     ldev = netdev_next_lower_dev_rcu(dev, &iter);
	     ldev;
	     ldev = netdev_next_lower_dev_rcu(dev, &iter)) {
		/* first is the lower device itself */
		ret = fn(ldev, data);
		if (ret)
			return ret;

		/* then look at all of its lower devices */
		ret = netdev_walk_all_lower_dev_rcu(ldev, fn, data);
		if (ret)
			return ret;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(netdev_walk_all_lower_dev_rcu);

5558 5559 5560 5561 5562 5563 5564 5565 5566 5567 5568 5569 5570 5571 5572 5573 5574 5575 5576 5577 5578
/**
 * 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
5579 5580 5581 5582 5583 5584 5585 5586 5587
/**
 * 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)
{
5588
	struct netdev_adjacent *upper;
J
Jiri Pirko 已提交
5589

5590
	upper = list_first_or_null_rcu(&dev->adj_list.upper,
5591
				       struct netdev_adjacent, list);
J
Jiri Pirko 已提交
5592 5593 5594 5595 5596 5597
	if (upper && likely(upper->master))
		return upper->dev;
	return NULL;
}
EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);

5598
static int netdev_adjacent_sysfs_add(struct net_device *dev,
5599 5600 5601 5602 5603 5604 5605 5606 5607
			      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);
}
5608
static void netdev_adjacent_sysfs_del(struct net_device *dev,
5609 5610 5611 5612 5613 5614 5615 5616 5617
			       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);
}

5618 5619 5620 5621 5622 5623 5624 5625
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));
}
5626

5627 5628
static int __netdev_adjacent_dev_insert(struct net_device *dev,
					struct net_device *adj_dev,
5629
					struct list_head *dev_list,
5630
					void *private, bool master)
5631 5632
{
	struct netdev_adjacent *adj;
5633
	int ret;
5634

5635
	adj = __netdev_find_adj(adj_dev, dev_list);
5636 5637

	if (adj) {
5638
		adj->ref_nr += 1;
5639 5640 5641
		pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n",
			 dev->name, adj_dev->name, adj->ref_nr);

5642 5643 5644 5645 5646 5647 5648 5649 5650
		return 0;
	}

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

	adj->dev = adj_dev;
	adj->master = master;
5651
	adj->ref_nr = 1;
5652
	adj->private = private;
5653
	dev_hold(adj_dev);
5654

5655 5656
	pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d; dev_hold on %s\n",
		 dev->name, adj_dev->name, adj->ref_nr, adj_dev->name);
5657

5658
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
5659
		ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
5660 5661 5662 5663
		if (ret)
			goto free_adj;
	}

5664
	/* Ensure that master link is always the first item in list. */
5665 5666 5667 5668
	if (master) {
		ret = sysfs_create_link(&(dev->dev.kobj),
					&(adj_dev->dev.kobj), "master");
		if (ret)
5669
			goto remove_symlinks;
5670

5671
		list_add_rcu(&adj->list, dev_list);
5672
	} else {
5673
		list_add_tail_rcu(&adj->list, dev_list);
5674
	}
5675 5676

	return 0;
5677

5678
remove_symlinks:
5679
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
5680
		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
5681 5682
free_adj:
	kfree(adj);
5683
	dev_put(adj_dev);
5684 5685

	return ret;
5686 5687
}

S
stephen hemminger 已提交
5688 5689
static void __netdev_adjacent_dev_remove(struct net_device *dev,
					 struct net_device *adj_dev,
5690
					 u16 ref_nr,
S
stephen hemminger 已提交
5691
					 struct list_head *dev_list)
5692 5693 5694
{
	struct netdev_adjacent *adj;

5695 5696 5697
	pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n",
		 dev->name, adj_dev->name, ref_nr);

5698
	adj = __netdev_find_adj(adj_dev, dev_list);
5699

5700
	if (!adj) {
5701
		pr_err("Adjacency does not exist for device %s from %s\n",
5702
		       dev->name, adj_dev->name);
5703 5704
		WARN_ON(1);
		return;
5705
	}
5706

5707
	if (adj->ref_nr > ref_nr) {
5708 5709 5710
		pr_debug("adjacency: %s to %s ref_nr - %d = %d\n",
			 dev->name, adj_dev->name, ref_nr,
			 adj->ref_nr - ref_nr);
5711
		adj->ref_nr -= ref_nr;
5712 5713 5714
		return;
	}

5715 5716 5717
	if (adj->master)
		sysfs_remove_link(&(dev->dev.kobj), "master");

5718
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
5719
		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
5720

5721
	list_del_rcu(&adj->list);
5722
	pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n",
5723
		 adj_dev->name, dev->name, adj_dev->name);
5724 5725 5726 5727
	dev_put(adj_dev);
	kfree_rcu(adj, rcu);
}

S
stephen hemminger 已提交
5728 5729 5730 5731 5732
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)
5733 5734 5735
{
	int ret;

5736
	ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list,
5737
					   private, master);
5738 5739 5740
	if (ret)
		return ret;

5741
	ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list,
5742
					   private, false);
5743
	if (ret) {
5744
		__netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list);
5745 5746 5747 5748 5749 5750
		return ret;
	}

	return 0;
}

S
stephen hemminger 已提交
5751 5752
static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
					       struct net_device *upper_dev,
5753
					       u16 ref_nr,
S
stephen hemminger 已提交
5754 5755
					       struct list_head *up_list,
					       struct list_head *down_list)
5756
{
5757 5758
	__netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list);
	__netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list);
5759 5760
}

S
stephen hemminger 已提交
5761 5762 5763
static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
						struct net_device *upper_dev,
						void *private, bool master)
5764
{
5765 5766 5767 5768
	return __netdev_adjacent_dev_link_lists(dev, upper_dev,
						&dev->adj_list.upper,
						&upper_dev->adj_list.lower,
						private, master);
5769 5770
}

S
stephen hemminger 已提交
5771 5772
static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
						   struct net_device *upper_dev)
5773
{
5774
	__netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1,
5775 5776 5777
					   &dev->adj_list.upper,
					   &upper_dev->adj_list.lower);
}
5778

J
Jiri Pirko 已提交
5779
static int __netdev_upper_dev_link(struct net_device *dev,
5780
				   struct net_device *upper_dev, bool master,
5781
				   void *upper_priv, void *upper_info)
J
Jiri Pirko 已提交
5782
{
5783
	struct netdev_notifier_changeupper_info changeupper_info;
5784
	int ret = 0;
J
Jiri Pirko 已提交
5785 5786 5787 5788 5789 5790 5791

	ASSERT_RTNL();

	if (dev == upper_dev)
		return -EBUSY;

	/* To prevent loops, check if dev is not upper device to upper_dev. */
5792
	if (netdev_has_upper_dev(upper_dev, dev))
J
Jiri Pirko 已提交
5793 5794
		return -EBUSY;

5795
	if (netdev_has_upper_dev(dev, upper_dev))
J
Jiri Pirko 已提交
5796 5797 5798 5799 5800
		return -EEXIST;

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

5801 5802 5803
	changeupper_info.upper_dev = upper_dev;
	changeupper_info.master = master;
	changeupper_info.linking = true;
5804
	changeupper_info.upper_info = upper_info;
5805

5806 5807 5808 5809 5810 5811
	ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, dev,
					    &changeupper_info.info);
	ret = notifier_to_errno(ret);
	if (ret)
		return ret;

5812
	ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv,
5813
						   master);
5814 5815
	if (ret)
		return ret;
J
Jiri Pirko 已提交
5816

5817 5818 5819 5820
	ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev,
					    &changeupper_info.info);
	ret = notifier_to_errno(ret);
	if (ret)
5821
		goto rollback;
5822

J
Jiri Pirko 已提交
5823
	return 0;
5824

5825
rollback:
5826
	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5827 5828

	return ret;
J
Jiri Pirko 已提交
5829 5830 5831 5832 5833 5834 5835 5836 5837 5838 5839 5840 5841 5842 5843
}

/**
 * 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)
{
5844
	return __netdev_upper_dev_link(dev, upper_dev, false, NULL, NULL);
J
Jiri Pirko 已提交
5845 5846 5847 5848 5849 5850 5851
}
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
5852
 * @upper_priv: upper device private
5853
 * @upper_info: upper info to be passed down via notifier
J
Jiri Pirko 已提交
5854 5855 5856 5857 5858 5859 5860 5861
 *
 * 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,
5862
				 struct net_device *upper_dev,
5863
				 void *upper_priv, void *upper_info)
J
Jiri Pirko 已提交
5864
{
5865 5866
	return __netdev_upper_dev_link(dev, upper_dev, true,
				       upper_priv, upper_info);
J
Jiri Pirko 已提交
5867 5868 5869 5870 5871 5872 5873 5874 5875 5876 5877 5878 5879 5880
}
EXPORT_SYMBOL(netdev_master_upper_dev_link);

/**
 * 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)
{
5881
	struct netdev_notifier_changeupper_info changeupper_info;
J
Jiri Pirko 已提交
5882 5883
	ASSERT_RTNL();

5884 5885 5886 5887
	changeupper_info.upper_dev = upper_dev;
	changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev;
	changeupper_info.linking = false;

5888 5889 5890
	call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, dev,
				      &changeupper_info.info);

5891
	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5892

5893 5894
	call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev,
				      &changeupper_info.info);
J
Jiri Pirko 已提交
5895 5896 5897
}
EXPORT_SYMBOL(netdev_upper_dev_unlink);

5898 5899 5900
/**
 * netdev_bonding_info_change - Dispatch event about slave change
 * @dev: device
5901
 * @bonding_info: info to dispatch
5902 5903 5904 5905 5906 5907 5908 5909 5910 5911 5912 5913 5914 5915 5916 5917
 *
 * 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
5918
static void netdev_adjacent_add_links(struct net_device *dev)
5919 5920 5921 5922 5923 5924
{
	struct netdev_adjacent *iter;

	struct net *net = dev_net(dev);

	list_for_each_entry(iter, &dev->adj_list.upper, list) {
W
Wei Tang 已提交
5925
		if (!net_eq(net, dev_net(iter->dev)))
5926 5927 5928 5929 5930 5931 5932 5933
			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) {
W
Wei Tang 已提交
5934
		if (!net_eq(net, dev_net(iter->dev)))
5935 5936 5937 5938 5939 5940 5941 5942
			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
5943
static void netdev_adjacent_del_links(struct net_device *dev)
5944 5945 5946 5947 5948 5949
{
	struct netdev_adjacent *iter;

	struct net *net = dev_net(dev);

	list_for_each_entry(iter, &dev->adj_list.upper, list) {
W
Wei Tang 已提交
5950
		if (!net_eq(net, dev_net(iter->dev)))
5951 5952 5953 5954 5955 5956 5957 5958
			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) {
W
Wei Tang 已提交
5959
		if (!net_eq(net, dev_net(iter->dev)))
5960 5961 5962 5963 5964 5965 5966 5967
			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);
	}
}

5968
void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
5969
{
5970
	struct netdev_adjacent *iter;
5971

5972 5973
	struct net *net = dev_net(dev);

5974
	list_for_each_entry(iter, &dev->adj_list.upper, list) {
W
Wei Tang 已提交
5975
		if (!net_eq(net, dev_net(iter->dev)))
5976
			continue;
5977 5978 5979 5980 5981
		netdev_adjacent_sysfs_del(iter->dev, oldname,
					  &iter->dev->adj_list.lower);
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.lower);
	}
5982

5983
	list_for_each_entry(iter, &dev->adj_list.lower, list) {
W
Wei Tang 已提交
5984
		if (!net_eq(net, dev_net(iter->dev)))
5985
			continue;
5986 5987 5988 5989 5990
		netdev_adjacent_sysfs_del(iter->dev, oldname,
					  &iter->dev->adj_list.upper);
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.upper);
	}
5991 5992 5993 5994 5995 5996 5997 5998 5999
}

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

	if (!lower_dev)
		return NULL;
6000
	lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower);
6001 6002 6003 6004 6005 6006 6007
	if (!lower)
		return NULL;

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

6008

6009
int dev_get_nest_level(struct net_device *dev)
6010 6011 6012 6013 6014 6015 6016 6017 6018
{
	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) {
6019
		nest = dev_get_nest_level(lower);
6020 6021 6022 6023
		if (max_nest < nest)
			max_nest = nest;
	}

6024
	return max_nest + 1;
6025 6026 6027
}
EXPORT_SYMBOL(dev_get_nest_level);

6028 6029 6030 6031 6032 6033 6034 6035 6036 6037 6038 6039 6040 6041 6042 6043 6044 6045 6046 6047
/**
 * netdev_lower_change - Dispatch event about lower device state change
 * @lower_dev: device
 * @lower_state_info: state to dispatch
 *
 * Send NETDEV_CHANGELOWERSTATE to netdev notifiers with info.
 * The caller must hold the RTNL lock.
 */
void netdev_lower_state_changed(struct net_device *lower_dev,
				void *lower_state_info)
{
	struct netdev_notifier_changelowerstate_info changelowerstate_info;

	ASSERT_RTNL();
	changelowerstate_info.lower_state_info = lower_state_info;
	call_netdevice_notifiers_info(NETDEV_CHANGELOWERSTATE, lower_dev,
				      &changelowerstate_info.info);
}
EXPORT_SYMBOL(netdev_lower_state_changed);

6048 6049 6050 6051 6052 6053 6054 6055 6056 6057 6058 6059 6060 6061 6062 6063 6064 6065 6066 6067 6068 6069 6070 6071 6072 6073 6074 6075 6076 6077 6078 6079 6080 6081 6082 6083 6084 6085 6086 6087 6088 6089 6090 6091
int netdev_default_l2upper_neigh_construct(struct net_device *dev,
					   struct neighbour *n)
{
	struct net_device *lower_dev, *stop_dev;
	struct list_head *iter;
	int err;

	netdev_for_each_lower_dev(dev, lower_dev, iter) {
		if (!lower_dev->netdev_ops->ndo_neigh_construct)
			continue;
		err = lower_dev->netdev_ops->ndo_neigh_construct(lower_dev, n);
		if (err) {
			stop_dev = lower_dev;
			goto rollback;
		}
	}
	return 0;

rollback:
	netdev_for_each_lower_dev(dev, lower_dev, iter) {
		if (lower_dev == stop_dev)
			break;
		if (!lower_dev->netdev_ops->ndo_neigh_destroy)
			continue;
		lower_dev->netdev_ops->ndo_neigh_destroy(lower_dev, n);
	}
	return err;
}
EXPORT_SYMBOL_GPL(netdev_default_l2upper_neigh_construct);

void netdev_default_l2upper_neigh_destroy(struct net_device *dev,
					  struct neighbour *n)
{
	struct net_device *lower_dev;
	struct list_head *iter;

	netdev_for_each_lower_dev(dev, lower_dev, iter) {
		if (!lower_dev->netdev_ops->ndo_neigh_destroy)
			continue;
		lower_dev->netdev_ops->ndo_neigh_destroy(lower_dev, n);
	}
}
EXPORT_SYMBOL_GPL(netdev_default_l2upper_neigh_destroy);

6092 6093
static void dev_change_rx_flags(struct net_device *dev, int flags)
{
6094 6095
	const struct net_device_ops *ops = dev->netdev_ops;

6096
	if (ops->ndo_change_rx_flags)
6097
		ops->ndo_change_rx_flags(dev, flags);
6098 6099
}

6100
static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
L
Linus Torvalds 已提交
6101
{
6102
	unsigned int old_flags = dev->flags;
6103 6104
	kuid_t uid;
	kgid_t gid;
L
Linus Torvalds 已提交
6105

6106 6107
	ASSERT_RTNL();

6108 6109 6110 6111 6112 6113 6114 6115 6116 6117 6118
	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;
6119 6120
			pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
				dev->name);
6121 6122 6123
			return -EOVERFLOW;
		}
	}
6124
	if (dev->flags != old_flags) {
6125 6126 6127
		pr_info("device %s %s promiscuous mode\n",
			dev->name,
			dev->flags & IFF_PROMISC ? "entered" : "left");
6128 6129
		if (audit_enabled) {
			current_uid_gid(&uid, &gid);
6130 6131 6132 6133 6134
			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),
6135
				from_kuid(&init_user_ns, audit_get_loginuid(current)),
6136 6137
				from_kuid(&init_user_ns, uid),
				from_kgid(&init_user_ns, gid),
6138
				audit_get_sessionid(current));
6139
		}
6140

6141
		dev_change_rx_flags(dev, IFF_PROMISC);
L
Linus Torvalds 已提交
6142
	}
6143 6144
	if (notify)
		__dev_notify_flags(dev, old_flags, IFF_PROMISC);
6145
	return 0;
L
Linus Torvalds 已提交
6146 6147
}

6148 6149 6150 6151 6152 6153 6154 6155 6156
/**
 *	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.
6157
 *	Return 0 if successful or a negative errno code on error.
6158
 */
6159
int dev_set_promiscuity(struct net_device *dev, int inc)
6160
{
6161
	unsigned int old_flags = dev->flags;
6162
	int err;
6163

6164
	err = __dev_set_promiscuity(dev, inc, true);
6165
	if (err < 0)
6166
		return err;
6167 6168
	if (dev->flags != old_flags)
		dev_set_rx_mode(dev);
6169
	return err;
6170
}
E
Eric Dumazet 已提交
6171
EXPORT_SYMBOL(dev_set_promiscuity);
6172

6173
static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
L
Linus Torvalds 已提交
6174
{
6175
	unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
L
Linus Torvalds 已提交
6176

6177 6178
	ASSERT_RTNL();

L
Linus Torvalds 已提交
6179
	dev->flags |= IFF_ALLMULTI;
6180 6181 6182 6183 6184 6185 6186 6187 6188 6189
	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;
6190 6191
			pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
				dev->name);
6192 6193 6194
			return -EOVERFLOW;
		}
	}
6195
	if (dev->flags ^ old_flags) {
6196
		dev_change_rx_flags(dev, IFF_ALLMULTI);
6197
		dev_set_rx_mode(dev);
6198 6199 6200
		if (notify)
			__dev_notify_flags(dev, old_flags,
					   dev->gflags ^ old_gflags);
6201
	}
6202
	return 0;
6203
}
6204 6205 6206 6207 6208 6209 6210 6211 6212 6213 6214 6215 6216 6217 6218 6219 6220 6221

/**
 *	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
6222
EXPORT_SYMBOL(dev_set_allmulti);
6223 6224 6225 6226

/*
 *	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
6227
 *	filtering it is put in promiscuous mode while unicast addresses
6228 6229 6230 6231
 *	are present.
 */
void __dev_set_rx_mode(struct net_device *dev)
{
6232 6233
	const struct net_device_ops *ops = dev->netdev_ops;

6234 6235 6236 6237 6238
	/* dev_open will call this function so the list will stay sane. */
	if (!(dev->flags&IFF_UP))
		return;

	if (!netif_device_present(dev))
6239
		return;
6240

6241
	if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
6242 6243 6244
		/* Unicast addresses changes may only happen under the rtnl,
		 * therefore calling __dev_set_promiscuity here is safe.
		 */
6245
		if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
6246
			__dev_set_promiscuity(dev, 1, false);
6247
			dev->uc_promisc = true;
6248
		} else if (netdev_uc_empty(dev) && dev->uc_promisc) {
6249
			__dev_set_promiscuity(dev, -1, false);
6250
			dev->uc_promisc = false;
6251 6252
		}
	}
6253 6254 6255

	if (ops->ndo_set_rx_mode)
		ops->ndo_set_rx_mode(dev);
6256 6257 6258 6259
}

void dev_set_rx_mode(struct net_device *dev)
{
6260
	netif_addr_lock_bh(dev);
6261
	__dev_set_rx_mode(dev);
6262
	netif_addr_unlock_bh(dev);
L
Linus Torvalds 已提交
6263 6264
}

6265 6266 6267 6268 6269 6270
/**
 *	dev_get_flags - get flags reported to userspace
 *	@dev: device
 *
 *	Get the combination of flag bits exported through APIs to userspace.
 */
6271
unsigned int dev_get_flags(const struct net_device *dev)
L
Linus Torvalds 已提交
6272
{
6273
	unsigned int flags;
L
Linus Torvalds 已提交
6274 6275 6276

	flags = (dev->flags & ~(IFF_PROMISC |
				IFF_ALLMULTI |
S
Stefan Rompf 已提交
6277 6278 6279
				IFF_RUNNING |
				IFF_LOWER_UP |
				IFF_DORMANT)) |
L
Linus Torvalds 已提交
6280 6281 6282
		(dev->gflags & (IFF_PROMISC |
				IFF_ALLMULTI));

S
Stefan Rompf 已提交
6283 6284 6285 6286 6287 6288 6289 6290
	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
6291 6292 6293

	return flags;
}
E
Eric Dumazet 已提交
6294
EXPORT_SYMBOL(dev_get_flags);
L
Linus Torvalds 已提交
6295

6296
int __dev_change_flags(struct net_device *dev, unsigned int flags)
L
Linus Torvalds 已提交
6297
{
6298
	unsigned int old_flags = dev->flags;
6299
	int ret;
L
Linus Torvalds 已提交
6300

6301 6302
	ASSERT_RTNL();

L
Linus Torvalds 已提交
6303 6304 6305 6306 6307 6308 6309 6310 6311 6312 6313 6314 6315 6316
	/*
	 *	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.
	 */

6317 6318
	if ((old_flags ^ flags) & IFF_MULTICAST)
		dev_change_rx_flags(dev, IFF_MULTICAST);
6319

6320
	dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
6321 6322 6323 6324 6325 6326 6327 6328

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

	ret = 0;
6329
	if ((old_flags ^ flags) & IFF_UP)
6330
		ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
L
Linus Torvalds 已提交
6331 6332

	if ((flags ^ dev->gflags) & IFF_PROMISC) {
E
Eric Dumazet 已提交
6333
		int inc = (flags & IFF_PROMISC) ? 1 : -1;
6334
		unsigned int old_flags = dev->flags;
E
Eric Dumazet 已提交
6335

L
Linus Torvalds 已提交
6336
		dev->gflags ^= IFF_PROMISC;
6337 6338 6339 6340

		if (__dev_set_promiscuity(dev, inc, false) >= 0)
			if (dev->flags != old_flags)
				dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
6341 6342 6343 6344 6345 6346 6347
	}

	/* 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
6348 6349
		int inc = (flags & IFF_ALLMULTI) ? 1 : -1;

L
Linus Torvalds 已提交
6350
		dev->gflags ^= IFF_ALLMULTI;
6351
		__dev_set_allmulti(dev, inc, false);
L
Linus Torvalds 已提交
6352 6353
	}

6354 6355 6356
	return ret;
}

6357 6358
void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
			unsigned int gchanges)
6359 6360 6361
{
	unsigned int changes = dev->flags ^ old_flags;

6362
	if (gchanges)
6363
		rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
6364

6365 6366 6367 6368 6369 6370 6371 6372
	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 &&
6373 6374 6375 6376 6377 6378 6379
	    (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);
	}
6380 6381 6382 6383 6384 6385 6386 6387 6388 6389
}

/**
 *	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.
 */
6390
int dev_change_flags(struct net_device *dev, unsigned int flags)
6391
{
6392
	int ret;
6393
	unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
6394 6395 6396 6397 6398

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

6399
	changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
6400
	__dev_notify_flags(dev, old_flags, changes);
L
Linus Torvalds 已提交
6401 6402
	return ret;
}
E
Eric Dumazet 已提交
6403
EXPORT_SYMBOL(dev_change_flags);
L
Linus Torvalds 已提交
6404

6405 6406 6407 6408 6409 6410 6411 6412 6413 6414 6415
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;
}

6416 6417 6418 6419 6420 6421 6422
/**
 *	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
6423 6424
int dev_set_mtu(struct net_device *dev, int new_mtu)
{
6425
	int err, orig_mtu;
L
Linus Torvalds 已提交
6426 6427 6428 6429

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

6430 6431 6432 6433
	/* MTU must be positive, and in range */
	if (new_mtu < 0 || new_mtu < dev->min_mtu) {
		net_err_ratelimited("%s: Invalid MTU %d requested, hw min %d\n",
				    dev->name, new_mtu, dev->min_mtu);
L
Linus Torvalds 已提交
6434
		return -EINVAL;
6435 6436 6437 6438
	}

	if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) {
		net_err_ratelimited("%s: Invalid MTU %d requested, hw max %d\n",
6439
				    dev->name, new_mtu, dev->max_mtu);
6440 6441
		return -EINVAL;
	}
L
Linus Torvalds 已提交
6442 6443 6444 6445

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

6446 6447 6448 6449
	err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
	err = notifier_to_errno(err);
	if (err)
		return err;
6450

6451 6452
	orig_mtu = dev->mtu;
	err = __dev_set_mtu(dev, new_mtu);
6453

6454 6455 6456 6457 6458 6459 6460 6461 6462 6463 6464
	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
6465 6466
	return err;
}
E
Eric Dumazet 已提交
6467
EXPORT_SYMBOL(dev_set_mtu);
L
Linus Torvalds 已提交
6468

6469 6470 6471 6472 6473 6474 6475 6476 6477 6478 6479
/**
 *	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);

6480 6481 6482 6483 6484 6485 6486
/**
 *	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
6487 6488
int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
{
6489
	const struct net_device_ops *ops = dev->netdev_ops;
L
Linus Torvalds 已提交
6490 6491
	int err;

6492
	if (!ops->ndo_set_mac_address)
L
Linus Torvalds 已提交
6493 6494 6495 6496 6497
		return -EOPNOTSUPP;
	if (sa->sa_family != dev->type)
		return -EINVAL;
	if (!netif_device_present(dev))
		return -ENODEV;
6498
	err = ops->ndo_set_mac_address(dev, sa);
6499 6500
	if (err)
		return err;
J
Jiri Pirko 已提交
6501
	dev->addr_assign_type = NET_ADDR_SET;
6502
	call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
6503
	add_device_randomness(dev->dev_addr, dev->addr_len);
6504
	return 0;
L
Linus Torvalds 已提交
6505
}
E
Eric Dumazet 已提交
6506
EXPORT_SYMBOL(dev_set_mac_address);
L
Linus Torvalds 已提交
6507

J
Jiri Pirko 已提交
6508 6509 6510
/**
 *	dev_change_carrier - Change device carrier
 *	@dev: device
6511
 *	@new_carrier: new value
J
Jiri Pirko 已提交
6512 6513 6514 6515 6516 6517 6518 6519 6520 6521 6522 6523 6524 6525 6526
 *
 *	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);

6527 6528 6529 6530 6531 6532 6533 6534
/**
 *	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,
6535
			 struct netdev_phys_item_id *ppid)
6536 6537 6538 6539 6540 6541 6542 6543 6544
{
	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);

6545 6546 6547 6548
/**
 *	dev_get_phys_port_name - Get device physical port name
 *	@dev: device
 *	@name: port name
6549
 *	@len: limit of bytes to copy to name
6550 6551 6552 6553 6554 6555 6556 6557 6558 6559 6560 6561 6562 6563
 *
 *	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);

6564 6565 6566 6567 6568 6569 6570 6571 6572 6573 6574 6575 6576 6577 6578 6579 6580 6581 6582 6583
/**
 *	dev_change_proto_down - update protocol port state information
 *	@dev: device
 *	@proto_down: new value
 *
 *	This info can be used by switch drivers to set the phys state of the
 *	port.
 */
int dev_change_proto_down(struct net_device *dev, bool proto_down)
{
	const struct net_device_ops *ops = dev->netdev_ops;

	if (!ops->ndo_change_proto_down)
		return -EOPNOTSUPP;
	if (!netif_device_present(dev))
		return -ENODEV;
	return ops->ndo_change_proto_down(dev, proto_down);
}
EXPORT_SYMBOL(dev_change_proto_down);

6584 6585 6586 6587 6588 6589 6590 6591 6592 6593 6594 6595 6596 6597 6598 6599 6600 6601 6602 6603 6604 6605 6606 6607 6608 6609 6610 6611 6612 6613 6614 6615
/**
 *	dev_change_xdp_fd - set or clear a bpf program for a device rx path
 *	@dev: device
 *	@fd: new program fd or negative value to clear
 *
 *	Set or clear a bpf program for a device
 */
int dev_change_xdp_fd(struct net_device *dev, int fd)
{
	const struct net_device_ops *ops = dev->netdev_ops;
	struct bpf_prog *prog = NULL;
	struct netdev_xdp xdp = {};
	int err;

	if (!ops->ndo_xdp)
		return -EOPNOTSUPP;
	if (fd >= 0) {
		prog = bpf_prog_get_type(fd, BPF_PROG_TYPE_XDP);
		if (IS_ERR(prog))
			return PTR_ERR(prog);
	}

	xdp.command = XDP_SETUP_PROG;
	xdp.prog = prog;
	err = ops->ndo_xdp(dev, &xdp);
	if (err < 0 && prog)
		bpf_prog_put(prog);

	return err;
}
EXPORT_SYMBOL(dev_change_xdp_fd);

L
Linus Torvalds 已提交
6616 6617
/**
 *	dev_new_index	-	allocate an ifindex
6618
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
6619 6620 6621 6622 6623
 *
 *	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.
 */
6624
static int dev_new_index(struct net *net)
L
Linus Torvalds 已提交
6625
{
6626
	int ifindex = net->ifindex;
L
Linus Torvalds 已提交
6627 6628 6629
	for (;;) {
		if (++ifindex <= 0)
			ifindex = 1;
6630
		if (!__dev_get_by_index(net, ifindex))
6631
			return net->ifindex = ifindex;
L
Linus Torvalds 已提交
6632 6633 6634 6635
	}
}

/* Delayed registration/unregisteration */
6636
static LIST_HEAD(net_todo_list);
6637
DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
L
Linus Torvalds 已提交
6638

6639
static void net_set_todo(struct net_device *dev)
L
Linus Torvalds 已提交
6640 6641
{
	list_add_tail(&dev->todo_list, &net_todo_list);
6642
	dev_net(dev)->dev_unreg_count++;
L
Linus Torvalds 已提交
6643 6644
}

6645
static void rollback_registered_many(struct list_head *head)
6646
{
6647
	struct net_device *dev, *tmp;
6648
	LIST_HEAD(close_head);
6649

6650 6651 6652
	BUG_ON(dev_boot_phase);
	ASSERT_RTNL();

6653
	list_for_each_entry_safe(dev, tmp, head, unreg_list) {
6654
		/* Some devices call without registering
6655 6656
		 * for initialization unwind. Remove those
		 * devices and proceed with the remaining.
6657 6658
		 */
		if (dev->reg_state == NETREG_UNINITIALIZED) {
6659 6660
			pr_debug("unregister_netdevice: device %s/%p never was registered\n",
				 dev->name, dev);
6661

6662
			WARN_ON(1);
6663 6664
			list_del(&dev->unreg_list);
			continue;
6665
		}
6666
		dev->dismantle = true;
6667
		BUG_ON(dev->reg_state != NETREG_REGISTERED);
6668
	}
6669

6670
	/* If device is running, close it first. */
6671 6672
	list_for_each_entry(dev, head, unreg_list)
		list_add_tail(&dev->close_list, &close_head);
6673
	dev_close_many(&close_head, true);
6674

6675
	list_for_each_entry(dev, head, unreg_list) {
6676 6677
		/* And unlink it from device chain. */
		unlist_netdevice(dev);
6678

6679 6680
		dev->reg_state = NETREG_UNREGISTERING;
	}
6681
	flush_all_backlogs();
6682 6683 6684

	synchronize_net();

6685
	list_for_each_entry(dev, head, unreg_list) {
6686 6687
		struct sk_buff *skb = NULL;

6688 6689
		/* Shutdown queueing discipline. */
		dev_shutdown(dev);
6690 6691


6692 6693 6694 6695
		/* Notify protocols, that we are about to destroy
		   this device. They should clean all the things.
		*/
		call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6696

6697 6698 6699 6700 6701
		if (!dev->rtnl_link_ops ||
		    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
			skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U,
						     GFP_KERNEL);

6702 6703 6704
		/*
		 *	Flush the unicast and multicast chains
		 */
6705
		dev_uc_flush(dev);
6706
		dev_mc_flush(dev);
6707

6708 6709
		if (dev->netdev_ops->ndo_uninit)
			dev->netdev_ops->ndo_uninit(dev);
6710

6711 6712
		if (skb)
			rtmsg_ifinfo_send(skb, dev, GFP_KERNEL);
6713

J
Jiri Pirko 已提交
6714 6715
		/* Notifier chain MUST detach us all upper devices. */
		WARN_ON(netdev_has_any_upper_dev(dev));
6716
		WARN_ON(netdev_has_any_lower_dev(dev));
6717

6718 6719
		/* Remove entries from kobject tree */
		netdev_unregister_kobject(dev);
6720 6721 6722 6723
#ifdef CONFIG_XPS
		/* Remove XPS queueing entries */
		netif_reset_xps_queues_gt(dev, 0);
#endif
6724
	}
6725

6726
	synchronize_net();
6727

6728
	list_for_each_entry(dev, head, unreg_list)
6729 6730 6731 6732 6733 6734 6735 6736 6737
		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
6738
	list_del(&single);
6739 6740
}

6741 6742 6743 6744 6745
static netdev_features_t netdev_sync_upper_features(struct net_device *lower,
	struct net_device *upper, netdev_features_t features)
{
	netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
	netdev_features_t feature;
6746
	int feature_bit;
6747

6748 6749
	for_each_netdev_feature(&upper_disables, feature_bit) {
		feature = __NETIF_F_BIT(feature_bit);
6750 6751 6752 6753 6754 6755 6756 6757 6758 6759 6760 6761 6762 6763 6764 6765
		if (!(upper->wanted_features & feature)
		    && (features & feature)) {
			netdev_dbg(lower, "Dropping feature %pNF, upper dev %s has it off.\n",
				   &feature, upper->name);
			features &= ~feature;
		}
	}

	return features;
}

static void netdev_sync_lower_features(struct net_device *upper,
	struct net_device *lower, netdev_features_t features)
{
	netdev_features_t upper_disables = NETIF_F_UPPER_DISABLES;
	netdev_features_t feature;
6766
	int feature_bit;
6767

6768 6769
	for_each_netdev_feature(&upper_disables, feature_bit) {
		feature = __NETIF_F_BIT(feature_bit);
6770 6771 6772 6773 6774 6775 6776 6777 6778 6779 6780 6781 6782
		if (!(features & feature) && (lower->features & feature)) {
			netdev_dbg(upper, "Disabling feature %pNF on lower dev %s.\n",
				   &feature, lower->name);
			lower->wanted_features &= ~feature;
			netdev_update_features(lower);

			if (unlikely(lower->features & feature))
				netdev_WARN(upper, "failed to disable %pNF on %s!\n",
					    &feature, lower->name);
		}
	}
}

6783 6784
static netdev_features_t netdev_fix_features(struct net_device *dev,
	netdev_features_t features)
6785
{
6786 6787 6788
	/* Fix illegal checksum combinations */
	if ((features & NETIF_F_HW_CSUM) &&
	    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
6789
		netdev_warn(dev, "mixed HW and IP checksum settings.\n");
6790 6791 6792
		features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
	}

6793
	/* TSO requires that SG is present as well. */
6794
	if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
6795
		netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
6796
		features &= ~NETIF_F_ALL_TSO;
6797 6798
	}

6799 6800 6801 6802 6803 6804 6805 6806 6807 6808 6809 6810 6811
	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;
	}

6812 6813 6814 6815
	/* TSO with IPv4 ID mangling requires IPv4 TSO be enabled */
	if ((features & NETIF_F_TSO_MANGLEID) && !(features & NETIF_F_TSO))
		features &= ~NETIF_F_TSO_MANGLEID;

6816 6817 6818 6819
	/* TSO ECN requires that TSO is present as well. */
	if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
		features &= ~NETIF_F_TSO_ECN;

6820 6821
	/* Software GSO depends on SG. */
	if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
6822
		netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
6823 6824 6825
		features &= ~NETIF_F_GSO;
	}

6826
	/* UFO needs SG and checksumming */
6827
	if (features & NETIF_F_UFO) {
6828
		/* maybe split UFO into V4 and V6? */
6829 6830 6831
		if (!(features & NETIF_F_HW_CSUM) &&
		    ((features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) !=
		     (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM))) {
6832
			netdev_dbg(dev,
6833
				"Dropping NETIF_F_UFO since no checksum offload features.\n");
6834 6835 6836 6837
			features &= ~NETIF_F_UFO;
		}

		if (!(features & NETIF_F_SG)) {
6838
			netdev_dbg(dev,
6839
				"Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
6840 6841 6842 6843
			features &= ~NETIF_F_UFO;
		}
	}

6844 6845 6846 6847 6848 6849 6850 6851
	/* GSO partial features require GSO partial be set */
	if ((features & dev->gso_partial_features) &&
	    !(features & NETIF_F_GSO_PARTIAL)) {
		netdev_dbg(dev,
			   "Dropping partially supported GSO features since no GSO partial.\n");
		features &= ~dev->gso_partial_features;
	}

J
Jiri Pirko 已提交
6852 6853 6854 6855 6856 6857 6858
#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;

6859 6860 6861
	return features;
}

6862
int __netdev_update_features(struct net_device *dev)
6863
{
6864
	struct net_device *upper, *lower;
6865
	netdev_features_t features;
6866
	struct list_head *iter;
6867
	int err = -1;
6868

6869 6870
	ASSERT_RTNL();

6871 6872 6873 6874 6875 6876 6877 6878
	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);

6879 6880 6881 6882
	/* some features can't be enabled if they're off an an upper device */
	netdev_for_each_upper_dev_rcu(dev, upper, iter)
		features = netdev_sync_upper_features(dev, upper, features);

6883
	if (dev->features == features)
6884
		goto sync_lower;
6885

6886 6887
	netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
		&dev->features, &features);
6888 6889 6890

	if (dev->netdev_ops->ndo_set_features)
		err = dev->netdev_ops->ndo_set_features(dev, features);
6891 6892
	else
		err = 0;
6893

6894
	if (unlikely(err < 0)) {
6895
		netdev_err(dev,
6896 6897
			"set_features() failed (%d); wanted %pNF, left %pNF\n",
			err, &features, &dev->features);
6898 6899 6900 6901
		/* return non-0 since some features might have changed and
		 * it's better to fire a spurious notification than miss it
		 */
		return -1;
6902 6903
	}

6904
sync_lower:
6905 6906 6907 6908 6909 6910
	/* some features must be disabled on lower devices when disabled
	 * on an upper device (think: bonding master or bridge)
	 */
	netdev_for_each_lower_dev(dev, lower, iter)
		netdev_sync_lower_features(dev, lower, features);

6911 6912 6913
	if (!err)
		dev->features = features;

6914
	return err < 0 ? 0 : 1;
6915 6916
}

6917 6918 6919 6920 6921 6922 6923 6924
/**
 *	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.
 */
6925 6926 6927 6928
void netdev_update_features(struct net_device *dev)
{
	if (__netdev_update_features(dev))
		netdev_features_change(dev);
6929 6930 6931
}
EXPORT_SYMBOL(netdev_update_features);

6932 6933 6934 6935 6936 6937 6938 6939 6940 6941 6942 6943 6944 6945 6946 6947 6948
/**
 *	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);

6949 6950 6951 6952 6953 6954 6955 6956 6957 6958 6959 6960 6961 6962 6963 6964 6965 6966 6967 6968 6969 6970 6971 6972 6973 6974 6975
/**
 *	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);

6976
#ifdef CONFIG_SYSFS
6977 6978 6979
static int netif_alloc_rx_queues(struct net_device *dev)
{
	unsigned int i, count = dev->num_rx_queues;
T
Tom Herbert 已提交
6980
	struct netdev_rx_queue *rx;
6981
	size_t sz = count * sizeof(*rx);
6982

T
Tom Herbert 已提交
6983
	BUG_ON(count < 1);
6984

6985 6986 6987 6988 6989 6990
	rx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!rx) {
		rx = vzalloc(sz);
		if (!rx)
			return -ENOMEM;
	}
T
Tom Herbert 已提交
6991 6992 6993
	dev->_rx = rx;

	for (i = 0; i < count; i++)
T
Tom Herbert 已提交
6994
		rx[i].dev = dev;
6995 6996
	return 0;
}
T
Tom Herbert 已提交
6997
#endif
6998

C
Changli Gao 已提交
6999 7000 7001 7002 7003 7004 7005
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;
7006
	netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
C
Changli Gao 已提交
7007
	queue->dev = dev;
T
Tom Herbert 已提交
7008 7009 7010
#ifdef CONFIG_BQL
	dql_init(&queue->dql, HZ);
#endif
C
Changli Gao 已提交
7011 7012
}

7013 7014
static void netif_free_tx_queues(struct net_device *dev)
{
W
WANG Cong 已提交
7015
	kvfree(dev->_tx);
7016 7017
}

7018 7019 7020 7021
static int netif_alloc_netdev_queues(struct net_device *dev)
{
	unsigned int count = dev->num_tx_queues;
	struct netdev_queue *tx;
7022
	size_t sz = count * sizeof(*tx);
7023

7024 7025
	if (count < 1 || count > 0xffff)
		return -EINVAL;
7026

7027 7028 7029 7030 7031 7032
	tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!tx) {
		tx = vzalloc(sz);
		if (!tx)
			return -ENOMEM;
	}
7033
	dev->_tx = tx;
T
Tom Herbert 已提交
7034

7035 7036
	netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
	spin_lock_init(&dev->tx_global_lock);
C
Changli Gao 已提交
7037 7038

	return 0;
7039 7040
}

7041 7042 7043 7044 7045 7046 7047 7048 7049 7050 7051
void netif_tx_stop_all_queues(struct net_device *dev)
{
	unsigned int i;

	for (i = 0; i < dev->num_tx_queues; i++) {
		struct netdev_queue *txq = netdev_get_tx_queue(dev, i);
		netif_tx_stop_queue(txq);
	}
}
EXPORT_SYMBOL(netif_tx_stop_all_queues);

L
Linus Torvalds 已提交
7052 7053 7054 7055 7056 7057 7058 7059 7060 7061 7062 7063 7064 7065 7066 7067 7068 7069 7070 7071
/**
 *	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;
7072
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
7073 7074 7075 7076

	BUG_ON(dev_boot_phase);
	ASSERT_RTNL();

7077 7078
	might_sleep();

L
Linus Torvalds 已提交
7079 7080
	/* When net_device's are persistent, this will be fatal. */
	BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
7081
	BUG_ON(!net);
L
Linus Torvalds 已提交
7082

7083
	spin_lock_init(&dev->addr_list_lock);
7084
	netdev_set_addr_lockdep_class(dev);
L
Linus Torvalds 已提交
7085

7086
	ret = dev_get_valid_name(net, dev, dev->name);
7087 7088 7089
	if (ret < 0)
		goto out;

L
Linus Torvalds 已提交
7090
	/* Init, if this function is available */
7091 7092
	if (dev->netdev_ops->ndo_init) {
		ret = dev->netdev_ops->ndo_init(dev);
L
Linus Torvalds 已提交
7093 7094 7095
		if (ret) {
			if (ret > 0)
				ret = -EIO;
7096
			goto out;
L
Linus Torvalds 已提交
7097 7098
		}
	}
7099

7100 7101
	if (((dev->hw_features | dev->features) &
	     NETIF_F_HW_VLAN_CTAG_FILTER) &&
7102 7103 7104 7105 7106 7107 7108
	    (!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;
	}

7109 7110 7111 7112 7113 7114
	ret = -EBUSY;
	if (!dev->ifindex)
		dev->ifindex = dev_new_index(net);
	else if (__dev_get_by_index(net, dev->ifindex))
		goto err_uninit;

7115 7116 7117 7118
	/* Transfer changeable features to wanted_features and enable
	 * software offloads (GSO and GRO).
	 */
	dev->hw_features |= NETIF_F_SOFT_FEATURES;
7119 7120
	dev->features |= NETIF_F_SOFT_FEATURES;
	dev->wanted_features = dev->features & dev->hw_features;
L
Linus Torvalds 已提交
7121

7122
	if (!(dev->flags & IFF_LOOPBACK))
7123
		dev->hw_features |= NETIF_F_NOCACHE_COPY;
7124

7125 7126 7127 7128 7129
	/* If IPv4 TCP segmentation offload is supported we should also
	 * allow the device to enable segmenting the frame with the option
	 * of ignoring a static IP ID value.  This doesn't enable the
	 * feature itself but allows the user to enable it later.
	 */
7130 7131
	if (dev->hw_features & NETIF_F_TSO)
		dev->hw_features |= NETIF_F_TSO_MANGLEID;
7132 7133 7134 7135 7136 7137
	if (dev->vlan_features & NETIF_F_TSO)
		dev->vlan_features |= NETIF_F_TSO_MANGLEID;
	if (dev->mpls_features & NETIF_F_TSO)
		dev->mpls_features |= NETIF_F_TSO_MANGLEID;
	if (dev->hw_enc_features & NETIF_F_TSO)
		dev->hw_enc_features |= NETIF_F_TSO_MANGLEID;
7138

7139
	/* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
7140
	 */
7141
	dev->vlan_features |= NETIF_F_HIGHDMA;
7142

7143 7144
	/* Make NETIF_F_SG inheritable to tunnel devices.
	 */
7145
	dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL;
7146

S
Simon Horman 已提交
7147 7148 7149 7150
	/* Make NETIF_F_SG inheritable to MPLS.
	 */
	dev->mpls_features |= NETIF_F_SG;

7151 7152 7153 7154 7155
	ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
	ret = notifier_to_errno(ret);
	if (ret)
		goto err_uninit;

7156
	ret = netdev_register_kobject(dev);
7157
	if (ret)
7158
		goto err_uninit;
7159 7160
	dev->reg_state = NETREG_REGISTERED;

7161
	__netdev_update_features(dev);
7162

L
Linus Torvalds 已提交
7163 7164 7165 7166 7167 7168 7169
	/*
	 *	Default initial state at registry is that the
	 *	device is present.
	 */

	set_bit(__LINK_STATE_PRESENT, &dev->state);

7170 7171
	linkwatch_init_dev(dev);

L
Linus Torvalds 已提交
7172 7173
	dev_init_scheduler(dev);
	dev_hold(dev);
7174
	list_netdevice(dev);
7175
	add_device_randomness(dev->dev_addr, dev->addr_len);
L
Linus Torvalds 已提交
7176

7177 7178 7179 7180 7181 7182 7183
	/* 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
7184
	/* Notify protocols, that a new device appeared. */
7185
	ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
7186
	ret = notifier_to_errno(ret);
7187 7188 7189 7190
	if (ret) {
		rollback_registered(dev);
		dev->reg_state = NETREG_UNREGISTERED;
	}
7191 7192 7193 7194
	/*
	 *	Prevent userspace races by waiting until the network
	 *	device is fully setup before sending notifications.
	 */
7195 7196
	if (!dev->rtnl_link_ops ||
	    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
7197
		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
L
Linus Torvalds 已提交
7198 7199 7200

out:
	return ret;
7201 7202

err_uninit:
7203 7204
	if (dev->netdev_ops->ndo_uninit)
		dev->netdev_ops->ndo_uninit(dev);
7205
	goto out;
L
Linus Torvalds 已提交
7206
}
E
Eric Dumazet 已提交
7207
EXPORT_SYMBOL(register_netdevice);
L
Linus Torvalds 已提交
7208

7209 7210 7211 7212 7213 7214 7215 7216 7217 7218 7219 7220 7221 7222 7223 7224 7225 7226 7227 7228 7229 7230 7231 7232 7233 7234 7235 7236 7237 7238 7239
/**
 *	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
7240 7241 7242 7243 7244
	/* Note : We dont allocate pcpu_refcnt for dummy devices,
	 * because users of this 'device' dont need to change
	 * its refcount.
	 */

7245 7246 7247 7248 7249
	return 0;
}
EXPORT_SYMBOL_GPL(init_dummy_netdev);


L
Linus Torvalds 已提交
7250 7251 7252 7253 7254 7255 7256 7257 7258
/**
 *	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.
 *
7259
 *	This is a wrapper around register_netdevice that takes the rtnl semaphore
L
Linus Torvalds 已提交
7260 7261 7262 7263 7264 7265 7266 7267 7268 7269 7270 7271 7272 7273
 *	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
7274 7275 7276 7277 7278 7279 7280 7281 7282 7283
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);

7284
/**
L
Linus Torvalds 已提交
7285
 * netdev_wait_allrefs - wait until all references are gone.
7286
 * @dev: target net_device
L
Linus Torvalds 已提交
7287 7288 7289 7290 7291 7292 7293
 *
 * 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
7294
 * call dev_put.
L
Linus Torvalds 已提交
7295 7296 7297 7298
 */
static void netdev_wait_allrefs(struct net_device *dev)
{
	unsigned long rebroadcast_time, warning_time;
E
Eric Dumazet 已提交
7299
	int refcnt;
L
Linus Torvalds 已提交
7300

7301 7302
	linkwatch_forget_dev(dev);

L
Linus Torvalds 已提交
7303
	rebroadcast_time = warning_time = jiffies;
E
Eric Dumazet 已提交
7304 7305 7306
	refcnt = netdev_refcnt_read(dev);

	while (refcnt != 0) {
L
Linus Torvalds 已提交
7307
		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
7308
			rtnl_lock();
L
Linus Torvalds 已提交
7309 7310

			/* Rebroadcast unregister notification */
7311
			call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
L
Linus Torvalds 已提交
7312

7313
			__rtnl_unlock();
7314
			rcu_barrier();
7315 7316
			rtnl_lock();

7317
			call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
L
Linus Torvalds 已提交
7318 7319 7320 7321 7322 7323 7324 7325 7326 7327 7328
			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();
			}

7329
			__rtnl_unlock();
L
Linus Torvalds 已提交
7330 7331 7332 7333 7334 7335

			rebroadcast_time = jiffies;
		}

		msleep(250);

E
Eric Dumazet 已提交
7336 7337
		refcnt = netdev_refcnt_read(dev);

L
Linus Torvalds 已提交
7338
		if (time_after(jiffies, warning_time + 10 * HZ)) {
7339 7340
			pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
				 dev->name, refcnt);
L
Linus Torvalds 已提交
7341 7342 7343 7344 7345 7346 7347 7348 7349 7350 7351 7352 7353 7354 7355 7356 7357 7358 7359
			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
7360
 * We are invoked by rtnl_unlock().
L
Linus Torvalds 已提交
7361
 * This allows us to deal with problems:
7362
 * 1) We can delete sysfs objects which invoke hotplug
L
Linus Torvalds 已提交
7363 7364 7365
 *    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
7366 7367 7368
 *
 * 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
7369 7370 7371
 */
void netdev_run_todo(void)
{
7372
	struct list_head list;
L
Linus Torvalds 已提交
7373 7374

	/* Snapshot list, allow later requests */
7375
	list_replace_init(&net_todo_list, &list);
H
Herbert Xu 已提交
7376 7377

	__rtnl_unlock();
7378

7379 7380

	/* Wait for rcu callbacks to finish before next phase */
7381 7382 7383
	if (!list_empty(&list))
		rcu_barrier();

L
Linus Torvalds 已提交
7384 7385
	while (!list_empty(&list)) {
		struct net_device *dev
7386
			= list_first_entry(&list, struct net_device, todo_list);
L
Linus Torvalds 已提交
7387 7388
		list_del(&dev->todo_list);

7389
		rtnl_lock();
7390
		call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
7391
		__rtnl_unlock();
7392

7393
		if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
7394
			pr_err("network todo '%s' but state %d\n",
7395 7396 7397 7398
			       dev->name, dev->reg_state);
			dump_stack();
			continue;
		}
L
Linus Torvalds 已提交
7399

7400
		dev->reg_state = NETREG_UNREGISTERED;
L
Linus Torvalds 已提交
7401

7402
		netdev_wait_allrefs(dev);
L
Linus Torvalds 已提交
7403

7404
		/* paranoia */
E
Eric Dumazet 已提交
7405
		BUG_ON(netdev_refcnt_read(dev));
7406 7407
		BUG_ON(!list_empty(&dev->ptype_all));
		BUG_ON(!list_empty(&dev->ptype_specific));
7408 7409
		WARN_ON(rcu_access_pointer(dev->ip_ptr));
		WARN_ON(rcu_access_pointer(dev->ip6_ptr));
7410
		WARN_ON(dev->dn_ptr);
L
Linus Torvalds 已提交
7411

7412 7413
		if (dev->destructor)
			dev->destructor(dev);
7414

7415 7416 7417 7418 7419 7420
		/* Report a network device has been unregistered */
		rtnl_lock();
		dev_net(dev)->dev_unreg_count--;
		__rtnl_unlock();
		wake_up(&netdev_unregistering_wq);

7421 7422
		/* Free network device */
		kobject_put(&dev->dev.kobj);
L
Linus Torvalds 已提交
7423 7424 7425
	}
}

7426 7427 7428 7429
/* Convert net_device_stats to rtnl_link_stats64. rtnl_link_stats64 has
 * all the same fields in the same order as net_device_stats, with only
 * the type differing, but rtnl_link_stats64 may have additional fields
 * at the end for newer counters.
7430
 */
7431 7432
void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
			     const struct net_device_stats *netdev_stats)
7433 7434
{
#if BITS_PER_LONG == 64
7435
	BUILD_BUG_ON(sizeof(*stats64) < sizeof(*netdev_stats));
7436
	memcpy(stats64, netdev_stats, sizeof(*stats64));
7437 7438 7439
	/* zero out counters that only exist in rtnl_link_stats64 */
	memset((char *)stats64 + sizeof(*netdev_stats), 0,
	       sizeof(*stats64) - sizeof(*netdev_stats));
7440
#else
7441
	size_t i, n = sizeof(*netdev_stats) / sizeof(unsigned long);
7442 7443 7444
	const unsigned long *src = (const unsigned long *)netdev_stats;
	u64 *dst = (u64 *)stats64;

7445
	BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64));
7446 7447
	for (i = 0; i < n; i++)
		dst[i] = src[i];
7448 7449 7450
	/* zero out counters that only exist in rtnl_link_stats64 */
	memset((char *)stats64 + n * sizeof(u64), 0,
	       sizeof(*stats64) - n * sizeof(u64));
7451 7452
#endif
}
7453
EXPORT_SYMBOL(netdev_stats_to_stats64);
7454

7455 7456 7457
/**
 *	dev_get_stats	- get network device statistics
 *	@dev: device to get statistics from
7458
 *	@storage: place to store stats
7459
 *
7460 7461 7462 7463
 *	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.
7464
 */
7465 7466
struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
					struct rtnl_link_stats64 *storage)
7467
{
7468 7469
	const struct net_device_ops *ops = dev->netdev_ops;

7470 7471
	if (ops->ndo_get_stats64) {
		memset(storage, 0, sizeof(*storage));
7472 7473
		ops->ndo_get_stats64(dev, storage);
	} else if (ops->ndo_get_stats) {
7474
		netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
7475 7476
	} else {
		netdev_stats_to_stats64(storage, &dev->stats);
7477
	}
7478
	storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
7479
	storage->tx_dropped += atomic_long_read(&dev->tx_dropped);
7480
	storage->rx_nohandler += atomic_long_read(&dev->rx_nohandler);
7481
	return storage;
R
Rusty Russell 已提交
7482
}
7483
EXPORT_SYMBOL(dev_get_stats);
R
Rusty Russell 已提交
7484

7485
struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
7486
{
7487
	struct netdev_queue *queue = dev_ingress_queue(dev);
7488

7489 7490 7491 7492 7493 7494 7495
#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
7496
	RCU_INIT_POINTER(queue->qdisc, &noop_qdisc);
7497 7498 7499 7500
	queue->qdisc_sleeping = &noop_qdisc;
	rcu_assign_pointer(dev->ingress_queue, queue);
#endif
	return queue;
7501 7502
}

7503 7504
static const struct ethtool_ops default_ethtool_ops;

7505 7506 7507 7508 7509 7510 7511 7512
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);

7513 7514 7515 7516
void netdev_freemem(struct net_device *dev)
{
	char *addr = (char *)dev - dev->padded;

W
WANG Cong 已提交
7517
	kvfree(addr);
7518 7519
}

L
Linus Torvalds 已提交
7520
/**
T
Tom Herbert 已提交
7521
 *	alloc_netdev_mqs - allocate network device
7522 7523 7524 7525 7526 7527
 *	@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
7528 7529
 *
 *	Allocates a struct net_device with private data area for driver use
L
Li Zhong 已提交
7530
 *	and performs basic initialization.  Also allocates subqueue structs
T
Tom Herbert 已提交
7531
 *	for each queue on the device.
L
Linus Torvalds 已提交
7532
 */
T
Tom Herbert 已提交
7533
struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
7534
		unsigned char name_assign_type,
T
Tom Herbert 已提交
7535 7536
		void (*setup)(struct net_device *),
		unsigned int txqs, unsigned int rxqs)
L
Linus Torvalds 已提交
7537 7538
{
	struct net_device *dev;
7539
	size_t alloc_size;
7540
	struct net_device *p;
L
Linus Torvalds 已提交
7541

7542 7543
	BUG_ON(strlen(name) >= sizeof(dev->name));

T
Tom Herbert 已提交
7544
	if (txqs < 1) {
7545
		pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
7546 7547 7548
		return NULL;
	}

7549
#ifdef CONFIG_SYSFS
T
Tom Herbert 已提交
7550
	if (rxqs < 1) {
7551
		pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
T
Tom Herbert 已提交
7552 7553 7554 7555
		return NULL;
	}
#endif

7556
	alloc_size = sizeof(struct net_device);
7557 7558
	if (sizeof_priv) {
		/* ensure 32-byte alignment of private area */
7559
		alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
7560 7561 7562
		alloc_size += sizeof_priv;
	}
	/* ensure 32-byte alignment of whole construct */
7563
	alloc_size += NETDEV_ALIGN - 1;
L
Linus Torvalds 已提交
7564

7565 7566 7567
	p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!p)
		p = vzalloc(alloc_size);
7568
	if (!p)
L
Linus Torvalds 已提交
7569 7570
		return NULL;

7571
	dev = PTR_ALIGN(p, NETDEV_ALIGN);
L
Linus Torvalds 已提交
7572
	dev->padded = (char *)dev - (char *)p;
7573

E
Eric Dumazet 已提交
7574 7575
	dev->pcpu_refcnt = alloc_percpu(int);
	if (!dev->pcpu_refcnt)
7576
		goto free_dev;
7577 7578

	if (dev_addr_init(dev))
E
Eric Dumazet 已提交
7579
		goto free_pcpu;
7580

7581
	dev_mc_init(dev);
7582
	dev_uc_init(dev);
J
Jiri Pirko 已提交
7583

7584
	dev_net_set(dev, &init_net);
L
Linus Torvalds 已提交
7585

7586
	dev->gso_max_size = GSO_MAX_SIZE;
7587
	dev->gso_max_segs = GSO_MAX_SEGS;
7588 7589 7590

	INIT_LIST_HEAD(&dev->napi_list);
	INIT_LIST_HEAD(&dev->unreg_list);
7591
	INIT_LIST_HEAD(&dev->close_list);
7592
	INIT_LIST_HEAD(&dev->link_watch_list);
7593 7594
	INIT_LIST_HEAD(&dev->adj_list.upper);
	INIT_LIST_HEAD(&dev->adj_list.lower);
7595 7596
	INIT_LIST_HEAD(&dev->ptype_all);
	INIT_LIST_HEAD(&dev->ptype_specific);
7597 7598 7599
#ifdef CONFIG_NET_SCHED
	hash_init(dev->qdisc_hash);
#endif
7600
	dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM;
7601 7602
	setup(dev);

7603
	if (!dev->tx_queue_len) {
7604
		dev->priv_flags |= IFF_NO_QUEUE;
7605 7606
		dev->tx_queue_len = 1;
	}
7607

T
Tom Herbert 已提交
7608 7609
	dev->num_tx_queues = txqs;
	dev->real_num_tx_queues = txqs;
7610
	if (netif_alloc_netdev_queues(dev))
7611
		goto free_all;
7612

7613
#ifdef CONFIG_SYSFS
T
Tom Herbert 已提交
7614 7615
	dev->num_rx_queues = rxqs;
	dev->real_num_rx_queues = rxqs;
T
Tom Herbert 已提交
7616
	if (netif_alloc_rx_queues(dev))
7617
		goto free_all;
E
Eric Dumazet 已提交
7618
#endif
T
Tom Herbert 已提交
7619

L
Linus Torvalds 已提交
7620
	strcpy(dev->name, name);
7621
	dev->name_assign_type = name_assign_type;
7622
	dev->group = INIT_NETDEV_GROUP;
7623 7624
	if (!dev->ethtool_ops)
		dev->ethtool_ops = &default_ethtool_ops;
7625 7626 7627

	nf_hook_ingress_init(dev);

L
Linus Torvalds 已提交
7628
	return dev;
7629

7630 7631 7632 7633
free_all:
	free_netdev(dev);
	return NULL;

E
Eric Dumazet 已提交
7634 7635
free_pcpu:
	free_percpu(dev->pcpu_refcnt);
7636 7637
free_dev:
	netdev_freemem(dev);
7638
	return NULL;
L
Linus Torvalds 已提交
7639
}
T
Tom Herbert 已提交
7640
EXPORT_SYMBOL(alloc_netdev_mqs);
L
Linus Torvalds 已提交
7641 7642 7643 7644 7645

/**
 *	free_netdev - free network device
 *	@dev: device
 *
7646 7647
 *	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
7648
 *	If this is the last reference then it will be freed.
7649
 *	Must be called in process context.
L
Linus Torvalds 已提交
7650 7651 7652
 */
void free_netdev(struct net_device *dev)
{
7653 7654
	struct napi_struct *p, *n;

7655
	might_sleep();
7656
	netif_free_tx_queues(dev);
7657
#ifdef CONFIG_SYSFS
7658
	kvfree(dev->_rx);
T
Tom Herbert 已提交
7659
#endif
7660

7661
	kfree(rcu_dereference_protected(dev->ingress_queue, 1));
7662

7663 7664 7665
	/* Flush device addresses */
	dev_addr_flush(dev);

7666 7667 7668
	list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
		netif_napi_del(p);

E
Eric Dumazet 已提交
7669 7670 7671
	free_percpu(dev->pcpu_refcnt);
	dev->pcpu_refcnt = NULL;

S
Stephen Hemminger 已提交
7672
	/*  Compatibility with error handling in drivers */
L
Linus Torvalds 已提交
7673
	if (dev->reg_state == NETREG_UNINITIALIZED) {
7674
		netdev_freemem(dev);
L
Linus Torvalds 已提交
7675 7676 7677 7678 7679 7680
		return;
	}

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

7681 7682
	/* will free via device release */
	put_device(&dev->dev);
L
Linus Torvalds 已提交
7683
}
E
Eric Dumazet 已提交
7684
EXPORT_SYMBOL(free_netdev);
7685

7686 7687 7688 7689 7690 7691
/**
 *	synchronize_net -  Synchronize with packet receive processing
 *
 *	Wait for packets currently being received to be done.
 *	Does not block later packets from starting.
 */
7692
void synchronize_net(void)
L
Linus Torvalds 已提交
7693 7694
{
	might_sleep();
7695 7696 7697 7698
	if (rtnl_is_locked())
		synchronize_rcu_expedited();
	else
		synchronize_rcu();
L
Linus Torvalds 已提交
7699
}
E
Eric Dumazet 已提交
7700
EXPORT_SYMBOL(synchronize_net);
L
Linus Torvalds 已提交
7701 7702

/**
7703
 *	unregister_netdevice_queue - remove device from the kernel
L
Linus Torvalds 已提交
7704
 *	@dev: device
7705
 *	@head: list
7706
 *
L
Linus Torvalds 已提交
7707
 *	This function shuts down a device interface and removes it
7708
 *	from the kernel tables.
7709
 *	If head not NULL, device is queued to be unregistered later.
L
Linus Torvalds 已提交
7710 7711 7712 7713 7714
 *
 *	Callers must hold the rtnl semaphore.  You may want
 *	unregister_netdev() instead of this.
 */

7715
void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
L
Linus Torvalds 已提交
7716
{
7717 7718
	ASSERT_RTNL();

7719
	if (head) {
7720
		list_move_tail(&dev->unreg_list, head);
7721 7722 7723 7724 7725
	} else {
		rollback_registered(dev);
		/* Finish processing unregister after unlock */
		net_set_todo(dev);
	}
L
Linus Torvalds 已提交
7726
}
7727
EXPORT_SYMBOL(unregister_netdevice_queue);
L
Linus Torvalds 已提交
7728

7729 7730 7731
/**
 *	unregister_netdevice_many - unregister many devices
 *	@head: list of devices
7732 7733 7734
 *
 *  Note: As most callers use a stack allocated list_head,
 *  we force a list_del() to make sure stack wont be corrupted later.
7735 7736 7737 7738 7739 7740 7741 7742 7743
 */
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);
7744
		list_del(head);
7745 7746
	}
}
7747
EXPORT_SYMBOL(unregister_netdevice_many);
7748

L
Linus Torvalds 已提交
7749 7750 7751 7752 7753
/**
 *	unregister_netdev - remove device from the kernel
 *	@dev: device
 *
 *	This function shuts down a device interface and removes it
7754
 *	from the kernel tables.
L
Linus Torvalds 已提交
7755 7756 7757 7758 7759 7760 7761 7762 7763 7764 7765 7766 7767
 *
 *	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);

7768 7769 7770 7771 7772 7773 7774 7775 7776 7777 7778 7779 7780 7781 7782 7783 7784 7785 7786 7787 7788 7789 7790 7791 7792 7793 7794 7795 7796 7797 7798
/**
 *	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;
7799
	if (net_eq(dev_net(dev), net))
7800 7801 7802 7803 7804 7805
		goto out;

	/* Pick the destination device name, and ensure
	 * we can use it in the destination network namespace.
	 */
	err = -EEXIST;
7806
	if (__dev_get_by_name(net, dev->name)) {
7807 7808 7809
		/* We get here if we can't use the current device name */
		if (!pat)
			goto out;
7810
		if (dev_get_valid_name(net, dev, pat) < 0)
7811 7812 7813 7814 7815 7816 7817 7818
			goto out;
	}

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

	/* If device is running close it first. */
7819
	dev_close(dev);
7820 7821 7822 7823 7824 7825 7826 7827 7828 7829 7830 7831

	/* 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.
7832 7833 7834 7835

	   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.
7836 7837
	*/
	call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
7838 7839
	rcu_barrier();
	call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
7840
	rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
7841 7842 7843 7844

	/*
	 *	Flush the unicast and multicast chains
	 */
7845
	dev_uc_flush(dev);
7846
	dev_mc_flush(dev);
7847

7848 7849
	/* Send a netdev-removed uevent to the old namespace */
	kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
7850
	netdev_adjacent_del_links(dev);
7851

7852
	/* Actually switch the network namespace */
7853
	dev_net_set(dev, net);
7854 7855

	/* If there is an ifindex conflict assign a new one */
7856
	if (__dev_get_by_index(net, dev->ifindex))
7857 7858
		dev->ifindex = dev_new_index(net);

7859 7860
	/* Send a netdev-add uevent to the new namespace */
	kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
7861
	netdev_adjacent_add_links(dev);
7862

7863
	/* Fixup kobjects */
7864
	err = device_rename(&dev->dev, dev->name);
7865
	WARN_ON(err);
7866 7867 7868 7869 7870 7871 7872

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

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

7873 7874 7875 7876
	/*
	 *	Prevent userspace races by waiting until the network
	 *	device is fully setup before sending notifications.
	 */
7877
	rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
7878

7879 7880 7881 7882 7883
	synchronize_net();
	err = 0;
out:
	return err;
}
7884
EXPORT_SYMBOL_GPL(dev_change_net_namespace);
7885

L
Linus Torvalds 已提交
7886 7887 7888 7889 7890 7891 7892 7893 7894
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;

7895
	if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
L
Linus Torvalds 已提交
7896 7897 7898 7899 7900 7901 7902 7903 7904 7905 7906 7907 7908 7909 7910 7911
		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. */
7912 7913 7914 7915 7916 7917
	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
7918 7919 7920 7921 7922 7923 7924 7925 7926 7927 7928 7929 7930 7931
	/* 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);
7932
	}
L
Linus Torvalds 已提交
7933 7934 7935 7936 7937

	raise_softirq_irqoff(NET_TX_SOFTIRQ);
	local_irq_enable();

	/* Process offline CPU's input_pkt_queue */
7938
	while ((skb = __skb_dequeue(&oldsd->process_queue))) {
7939
		netif_rx_ni(skb);
7940
		input_queue_head_incr(oldsd);
T
Tom Herbert 已提交
7941
	}
E
Eric Dumazet 已提交
7942
	while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
7943
		netif_rx_ni(skb);
7944 7945
		input_queue_head_incr(oldsd);
	}
L
Linus Torvalds 已提交
7946 7947 7948 7949 7950

	return NOTIFY_OK;
}


7951
/**
7952 7953 7954 7955
 *	netdev_increment_features - increment feature set by one
 *	@all: current feature set
 *	@one: new feature set
 *	@mask: mask feature set
7956 7957
 *
 *	Computes a new feature set after adding a device with feature set
7958 7959
 *	@one to the master device with current feature set @all.  Will not
 *	enable anything that is off in @mask. Returns the new feature set.
7960
 */
7961 7962
netdev_features_t netdev_increment_features(netdev_features_t all,
	netdev_features_t one, netdev_features_t mask)
7963
{
7964
	if (mask & NETIF_F_HW_CSUM)
7965
		mask |= NETIF_F_CSUM_MASK;
7966
	mask |= NETIF_F_VLAN_CHALLENGED;
7967

7968
	all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask;
7969
	all &= one | ~NETIF_F_ALL_FOR_ALL;
7970

7971
	/* If one device supports hw checksumming, set for all. */
7972 7973
	if (all & NETIF_F_HW_CSUM)
		all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM);
7974 7975 7976

	return all;
}
7977
EXPORT_SYMBOL(netdev_increment_features);
7978

7979
static struct hlist_head * __net_init netdev_create_hash(void)
7980 7981 7982 7983 7984 7985 7986 7987 7988 7989 7990 7991
{
	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;
}

7992
/* Initialize per network namespace state */
7993
static int __net_init netdev_init(struct net *net)
7994
{
7995 7996
	if (net != &init_net)
		INIT_LIST_HEAD(&net->dev_base_head);
7997

7998 7999 8000
	net->dev_name_head = netdev_create_hash();
	if (net->dev_name_head == NULL)
		goto err_name;
8001

8002 8003 8004
	net->dev_index_head = netdev_create_hash();
	if (net->dev_index_head == NULL)
		goto err_idx;
8005 8006

	return 0;
8007 8008 8009 8010 8011

err_idx:
	kfree(net->dev_name_head);
err_name:
	return -ENOMEM;
8012 8013
}

8014 8015 8016 8017 8018 8019
/**
 *	netdev_drivername - network driver for the device
 *	@dev: network device
 *
 *	Determine network driver for device.
 */
8020
const char *netdev_drivername(const struct net_device *dev)
8021
{
8022 8023
	const struct device_driver *driver;
	const struct device *parent;
8024
	const char *empty = "";
8025 8026 8027

	parent = dev->dev.parent;
	if (!parent)
8028
		return empty;
8029 8030 8031

	driver = parent->driver;
	if (driver && driver->name)
8032 8033
		return driver->name;
	return empty;
8034 8035
}

8036 8037
static void __netdev_printk(const char *level, const struct net_device *dev,
			    struct va_format *vaf)
8038
{
8039
	if (dev && dev->dev.parent) {
8040 8041 8042 8043 8044 8045 8046
		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);
8047
	} else if (dev) {
8048 8049
		printk("%s%s%s: %pV",
		       level, netdev_name(dev), netdev_reg_state(dev), vaf);
8050
	} else {
8051
		printk("%s(NULL net_device): %pV", level, vaf);
8052
	}
8053 8054
}

8055 8056
void netdev_printk(const char *level, const struct net_device *dev,
		   const char *format, ...)
8057 8058 8059 8060 8061 8062 8063 8064 8065
{
	struct va_format vaf;
	va_list args;

	va_start(args, format);

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

8066
	__netdev_printk(level, dev, &vaf);
8067

8068 8069 8070 8071 8072
	va_end(args);
}
EXPORT_SYMBOL(netdev_printk);

#define define_netdev_printk_level(func, level)			\
8073
void func(const struct net_device *dev, const char *fmt, ...)	\
8074 8075 8076 8077 8078 8079 8080 8081 8082
{								\
	struct va_format vaf;					\
	va_list args;						\
								\
	va_start(args, fmt);					\
								\
	vaf.fmt = fmt;						\
	vaf.va = &args;						\
								\
8083
	__netdev_printk(level, dev, &vaf);			\
8084
								\
8085 8086 8087 8088 8089 8090 8091 8092 8093 8094 8095 8096
	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);

8097
static void __net_exit netdev_exit(struct net *net)
8098 8099 8100 8101 8102
{
	kfree(net->dev_name_head);
	kfree(net->dev_index_head);
}

8103
static struct pernet_operations __net_initdata netdev_net_ops = {
8104 8105 8106 8107
	.init = netdev_init,
	.exit = netdev_exit,
};

8108
static void __net_exit default_device_exit(struct net *net)
8109
{
8110
	struct net_device *dev, *aux;
8111
	/*
8112
	 * Push all migratable network devices back to the
8113 8114 8115
	 * initial network namespace
	 */
	rtnl_lock();
8116
	for_each_netdev_safe(net, dev, aux) {
8117
		int err;
8118
		char fb_name[IFNAMSIZ];
8119 8120 8121 8122 8123

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

8124 8125 8126
		/* Leave virtual devices for the generic cleanup */
		if (dev->rtnl_link_ops)
			continue;
8127

L
Lucas De Marchi 已提交
8128
		/* Push remaining network devices to init_net */
8129 8130
		snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
		err = dev_change_net_namespace(dev, &init_net, fb_name);
8131
		if (err) {
8132 8133
			pr_emerg("%s: failed to move %s to init_net: %d\n",
				 __func__, dev->name, err);
8134
			BUG();
8135 8136 8137 8138 8139
		}
	}
	rtnl_unlock();
}

8140 8141 8142 8143 8144 8145 8146
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;
8147
	DEFINE_WAIT_FUNC(wait, woken_wake_function);
8148

8149
	add_wait_queue(&netdev_unregistering_wq, &wait);
8150 8151 8152 8153 8154 8155 8156 8157 8158 8159 8160 8161
	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();
8162 8163

		wait_woken(&wait, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
8164
	}
8165
	remove_wait_queue(&netdev_unregistering_wq, &wait);
8166 8167
}

8168 8169 8170
static void __net_exit default_device_exit_batch(struct list_head *net_list)
{
	/* At exit all network devices most be removed from a network
8171
	 * namespace.  Do this in the reverse order of registration.
8172 8173 8174 8175 8176 8177 8178
	 * 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);

8179 8180 8181 8182 8183 8184 8185 8186 8187 8188 8189 8190
	/* 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);
8191 8192
	list_for_each_entry(net, net_list, exit_list) {
		for_each_netdev_reverse(net, dev) {
8193
			if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink)
8194 8195 8196 8197 8198 8199 8200 8201 8202
				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();
}

8203
static struct pernet_operations __net_initdata default_device_ops = {
8204
	.exit = default_device_exit,
8205
	.exit_batch = default_device_exit_batch,
8206 8207
};

L
Linus Torvalds 已提交
8208 8209 8210 8211 8212 8213 8214 8215 8216 8217 8218 8219 8220 8221 8222 8223 8224 8225 8226 8227
/*
 *	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;

8228
	if (netdev_kobject_init())
L
Linus Torvalds 已提交
8229 8230 8231
		goto out;

	INIT_LIST_HEAD(&ptype_all);
8232
	for (i = 0; i < PTYPE_HASH_SIZE; i++)
L
Linus Torvalds 已提交
8233 8234
		INIT_LIST_HEAD(&ptype_base[i]);

8235 8236
	INIT_LIST_HEAD(&offload_base);

8237 8238
	if (register_pernet_subsys(&netdev_net_ops))
		goto out;
L
Linus Torvalds 已提交
8239 8240 8241 8242 8243

	/*
	 *	Initialise the packet receive queues.
	 */

8244
	for_each_possible_cpu(i) {
8245
		struct work_struct *flush = per_cpu_ptr(&flush_works, i);
E
Eric Dumazet 已提交
8246
		struct softnet_data *sd = &per_cpu(softnet_data, i);
L
Linus Torvalds 已提交
8247

8248 8249
		INIT_WORK(flush, flush_backlog);

E
Eric Dumazet 已提交
8250
		skb_queue_head_init(&sd->input_pkt_queue);
8251
		skb_queue_head_init(&sd->process_queue);
E
Eric Dumazet 已提交
8252
		INIT_LIST_HEAD(&sd->poll_list);
8253
		sd->output_queue_tailp = &sd->output_queue;
E
Eric Dumazet 已提交
8254
#ifdef CONFIG_RPS
E
Eric Dumazet 已提交
8255 8256 8257
		sd->csd.func = rps_trigger_softirq;
		sd->csd.info = sd;
		sd->cpu = i;
8258
#endif
T
Tom Herbert 已提交
8259

E
Eric Dumazet 已提交
8260 8261
		sd->backlog.poll = process_backlog;
		sd->backlog.weight = weight_p;
L
Linus Torvalds 已提交
8262 8263 8264 8265
	}

	dev_boot_phase = 0;

8266 8267 8268 8269 8270 8271 8272 8273 8274 8275 8276 8277 8278 8279 8280
	/* 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;

8281 8282
	open_softirq(NET_TX_SOFTIRQ, net_tx_action);
	open_softirq(NET_RX_SOFTIRQ, net_rx_action);
L
Linus Torvalds 已提交
8283 8284

	hotcpu_notifier(dev_cpu_callback, 0);
T
Thomas Graf 已提交
8285
	dst_subsys_init();
L
Linus Torvalds 已提交
8286 8287 8288 8289 8290 8291
	rc = 0;
out:
	return rc;
}

subsys_initcall(net_dev_init);