dev.c 207.4 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
static bool remove_xps_queue_cpu(struct net_device *dev,
				 struct xps_dev_maps *dev_maps,
				 int cpu, u16 offset, u16 count)
{
2005 2006 2007
	int num_tc = dev->num_tc ? : 1;
	bool active = false;
	int tci;
2008

2009 2010 2011 2012 2013 2014 2015 2016 2017
	for (tci = cpu * num_tc; num_tc--; tci++) {
		int i, j;

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

		active |= i < 0;
2018 2019
	}

2020
	return active;
2021 2022 2023 2024
}

static void netif_reset_xps_queues(struct net_device *dev, u16 offset,
				   u16 count)
2025 2026
{
	struct xps_dev_maps *dev_maps;
2027
	int cpu, i;
2028 2029 2030 2031 2032 2033 2034 2035
	bool active = false;

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

	if (!dev_maps)
		goto out_no_maps;

2036 2037 2038
	for_each_possible_cpu(cpu)
		active |= remove_xps_queue_cpu(dev, dev_maps, cpu,
					       offset, count);
2039 2040

	if (!active) {
2041 2042 2043 2044
		RCU_INIT_POINTER(dev->xps_maps, NULL);
		kfree_rcu(dev_maps, rcu);
	}

2045
	for (i = offset + (count - 1); count--; i--)
2046 2047 2048
		netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
					     NUMA_NO_NODE);

2049 2050 2051 2052
out_no_maps:
	mutex_unlock(&xps_map_mutex);
}

2053 2054 2055 2056 2057
static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
{
	netif_reset_xps_queues(dev, index, dev->num_tx_queues - index);
}

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 2085 2086 2087 2088 2089 2090 2091 2092
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;
}

2093 2094
int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
			u16 index)
2095
{
2096
	struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
2097 2098
	int i, cpu, tci, numa_node_id = -2;
	int maps_sz, num_tc = 1, tc = 0;
2099
	struct xps_map *map, *new_map;
2100
	bool active = false;
2101

2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112
	if (dev->num_tc) {
		num_tc = dev->num_tc;
		tc = netdev_txq_to_tc(dev, index);
		if (tc < 0)
			return -EINVAL;
	}

	maps_sz = XPS_DEV_MAPS_SIZE(num_tc);
	if (maps_sz < L1_CACHE_BYTES)
		maps_sz = L1_CACHE_BYTES;

2113 2114 2115 2116
	mutex_lock(&xps_map_mutex);

	dev_maps = xmap_dereference(dev->xps_maps);

2117
	/* allocate memory for queue storage */
2118
	for_each_cpu_and(cpu, cpu_online_mask, mask) {
2119 2120
		if (!new_dev_maps)
			new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
2121 2122
		if (!new_dev_maps) {
			mutex_unlock(&xps_map_mutex);
2123
			return -ENOMEM;
2124
		}
2125

2126 2127
		tci = cpu * num_tc + tc;
		map = dev_maps ? xmap_dereference(dev_maps->cpu_map[tci]) :
2128 2129 2130 2131 2132 2133
				 NULL;

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

2134
		RCU_INIT_POINTER(new_dev_maps->cpu_map[tci], map);
2135 2136 2137 2138 2139
	}

	if (!new_dev_maps)
		goto out_no_new_maps;

2140
	for_each_possible_cpu(cpu) {
2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152
		/* copy maps belonging to foreign traffic classes */
		for (i = tc, tci = cpu * num_tc; dev_maps && i--; tci++) {
			/* fill in the new device map from the old device map */
			map = xmap_dereference(dev_maps->cpu_map[tci]);
			RCU_INIT_POINTER(new_dev_maps->cpu_map[tci], map);
		}

		/* We need to explicitly update tci as prevous loop
		 * could break out early if dev_maps is NULL.
		 */
		tci = cpu * num_tc + tc;

2153 2154 2155 2156
		if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) {
			/* add queue to CPU maps */
			int pos = 0;

2157
			map = xmap_dereference(new_dev_maps->cpu_map[tci]);
2158 2159 2160 2161 2162
			while ((pos < map->len) && (map->queues[pos] != index))
				pos++;

			if (pos == map->len)
				map->queues[map->len++] = index;
2163 2164 2165 2166 2167 2168
#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
2169 2170
		} else if (dev_maps) {
			/* fill in the new device map from the old device map */
2171 2172
			map = xmap_dereference(dev_maps->cpu_map[tci]);
			RCU_INIT_POINTER(new_dev_maps->cpu_map[tci], map);
2173
		}
2174

2175 2176 2177 2178 2179 2180
		/* copy maps belonging to foreign traffic classes */
		for (i = num_tc - tc, tci++; dev_maps && --i; tci++) {
			/* fill in the new device map from the old device map */
			map = xmap_dereference(dev_maps->cpu_map[tci]);
			RCU_INIT_POINTER(new_dev_maps->cpu_map[tci], map);
		}
2181 2182
	}

2183 2184
	rcu_assign_pointer(dev->xps_maps, new_dev_maps);

2185
	/* Cleanup old maps */
2186 2187 2188 2189 2190 2191 2192
	if (!dev_maps)
		goto out_no_old_maps;

	for_each_possible_cpu(cpu) {
		for (i = num_tc, tci = cpu * num_tc; i--; tci++) {
			new_map = xmap_dereference(new_dev_maps->cpu_map[tci]);
			map = xmap_dereference(dev_maps->cpu_map[tci]);
2193 2194 2195
			if (map && map != new_map)
				kfree_rcu(map, rcu);
		}
2196 2197
	}

2198 2199 2200
	kfree_rcu(dev_maps, rcu);

out_no_old_maps:
2201 2202
	dev_maps = new_dev_maps;
	active = true;
2203

2204 2205
out_no_new_maps:
	/* update Tx queue numa node */
2206 2207 2208 2209
	netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
				     (numa_node_id >= 0) ? numa_node_id :
				     NUMA_NO_NODE);

2210 2211 2212 2213 2214
	if (!dev_maps)
		goto out_no_maps;

	/* removes queue from unused CPUs */
	for_each_possible_cpu(cpu) {
2215 2216 2217 2218 2219 2220
		for (i = tc, tci = cpu * num_tc; i--; tci++)
			active |= remove_xps_queue(dev_maps, tci, index);
		if (!cpumask_test_cpu(cpu, mask) || !cpu_online(cpu))
			active |= remove_xps_queue(dev_maps, tci, index);
		for (i = num_tc - tc, tci++; --i; tci++)
			active |= remove_xps_queue(dev_maps, tci, index);
2221 2222 2223 2224 2225 2226 2227 2228 2229
	}

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

out_no_maps:
2230 2231 2232 2233
	mutex_unlock(&xps_map_mutex);

	return 0;
error:
2234 2235
	/* remove any maps that we added */
	for_each_possible_cpu(cpu) {
2236 2237 2238 2239 2240 2241 2242 2243
		for (i = num_tc, tci = cpu * num_tc; i--; tci++) {
			new_map = xmap_dereference(new_dev_maps->cpu_map[tci]);
			map = dev_maps ?
			      xmap_dereference(dev_maps->cpu_map[tci]) :
			      NULL;
			if (new_map && new_map != map)
				kfree(new_map);
		}
2244 2245
	}

2246 2247 2248 2249 2250 2251 2252 2253
	mutex_unlock(&xps_map_mutex);

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

#endif
2254 2255
void netdev_reset_tc(struct net_device *dev)
{
2256 2257 2258
#ifdef CONFIG_XPS
	netif_reset_xps_queues_gt(dev, 0);
#endif
2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269
	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;

2270 2271 2272
#ifdef CONFIG_XPS
	netif_reset_xps_queues(dev, offset, count);
#endif
2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283
	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;

2284 2285 2286
#ifdef CONFIG_XPS
	netif_reset_xps_queues_gt(dev, 0);
#endif
2287 2288 2289 2290 2291
	dev->num_tc = num_tc;
	return 0;
}
EXPORT_SYMBOL(netdev_set_num_tc);

2292 2293 2294 2295
/*
 * 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.
 */
2296
int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
2297
{
T
Tom Herbert 已提交
2298 2299
	int rc;

2300 2301
	if (txq < 1 || txq > dev->num_tx_queues)
		return -EINVAL;
2302

2303 2304
	if (dev->reg_state == NETREG_REGISTERED ||
	    dev->reg_state == NETREG_UNREGISTERING) {
2305 2306
		ASSERT_RTNL();

T
Tom Herbert 已提交
2307 2308
		rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
						  txq);
T
Tom Herbert 已提交
2309 2310 2311
		if (rc)
			return rc;

2312 2313 2314
		if (dev->num_tc)
			netif_setup_tc(dev, txq);

2315
		if (txq < dev->real_num_tx_queues) {
2316
			qdisc_reset_all_tx_gt(dev, txq);
2317 2318 2319 2320
#ifdef CONFIG_XPS
			netif_reset_xps_queues_gt(dev, txq);
#endif
		}
2321
	}
2322 2323 2324

	dev->real_num_tx_queues = txq;
	return 0;
2325 2326
}
EXPORT_SYMBOL(netif_set_real_num_tx_queues);
2327

2328
#ifdef CONFIG_SYSFS
2329 2330 2331 2332 2333 2334 2335
/**
 *	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
2336 2337
 *	negative error code.  If called before registration, it always
 *	succeeds.
2338 2339 2340 2341 2342
 */
int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
{
	int rc;

T
Tom Herbert 已提交
2343 2344 2345
	if (rxq < 1 || rxq > dev->num_rx_queues)
		return -EINVAL;

2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360
	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

2361 2362
/**
 * netif_get_num_default_rss_queues - default number of RSS queues
2363 2364 2365 2366
 *
 * This routine should set an upper limit on the number of RSS queues
 * used by default by multiqueue devices.
 */
2367
int netif_get_num_default_rss_queues(void)
2368
{
2369 2370
	return is_kdump_kernel() ?
		1 : min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
2371 2372 2373
}
EXPORT_SYMBOL(netif_get_num_default_rss_queues);

2374
static void __netif_reschedule(struct Qdisc *q)
2375
{
2376 2377
	struct softnet_data *sd;
	unsigned long flags;
2378

2379
	local_irq_save(flags);
2380
	sd = this_cpu_ptr(&softnet_data);
2381 2382 2383
	q->next_sched = NULL;
	*sd->output_queue_tailp = q;
	sd->output_queue_tailp = &q->next_sched;
2384 2385 2386 2387 2388 2389 2390 2391
	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);
2392 2393 2394
}
EXPORT_SYMBOL(__netif_schedule);

2395 2396 2397 2398 2399
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)
2400
{
2401 2402 2403
	return (struct dev_kfree_skb_cb *)skb->cb;
}

2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450
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);

2451
void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
2452
{
2453
	unsigned long flags;
2454

2455 2456 2457 2458 2459
	if (likely(atomic_read(&skb->users) == 1)) {
		smp_rmb();
		atomic_set(&skb->users, 0);
	} else if (likely(!atomic_dec_and_test(&skb->users))) {
		return;
2460
	}
2461 2462 2463 2464 2465 2466
	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);
2467
}
2468
EXPORT_SYMBOL(__dev_kfree_skb_irq);
2469

2470
void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
2471 2472
{
	if (in_irq() || irqs_disabled())
2473
		__dev_kfree_skb_irq(skb, reason);
2474 2475 2476
	else
		dev_kfree_skb(skb);
}
2477
EXPORT_SYMBOL(__dev_kfree_skb_any);
2478 2479


2480 2481 2482 2483 2484 2485
/**
 * netif_device_detach - mark device as removed
 * @dev: network device
 *
 * Mark device as removed from system and therefore no longer available.
 */
2486 2487 2488 2489
void netif_device_detach(struct net_device *dev)
{
	if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
	    netif_running(dev)) {
2490
		netif_tx_stop_all_queues(dev);
2491 2492 2493 2494
	}
}
EXPORT_SYMBOL(netif_device_detach);

2495 2496 2497 2498 2499 2500
/**
 * netif_device_attach - mark device as attached
 * @dev: network device
 *
 * Mark device as attached from system and restart if needed.
 */
2501 2502 2503 2504
void netif_device_attach(struct net_device *dev)
{
	if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
	    netif_running(dev)) {
2505
		netif_tx_wake_all_queues(dev);
2506
		__netdev_watchdog_up(dev);
2507 2508 2509 2510
	}
}
EXPORT_SYMBOL(netif_device_attach);

J
Jiri Pirko 已提交
2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538
/*
 * 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);

2539 2540
static void skb_warn_bad_offload(const struct sk_buff *skb)
{
W
Wei Tang 已提交
2541
	static const netdev_features_t null_features;
2542
	struct net_device *dev = skb->dev;
2543
	const char *name = "";
2544

2545 2546 2547
	if (!net_ratelimit())
		return;

2548 2549 2550 2551 2552 2553
	if (dev) {
		if (dev->dev.parent)
			name = dev_driver_string(dev->dev.parent);
		else
			name = netdev_name(dev);
	}
2554 2555
	WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
	     "gso_type=%d ip_summed=%d\n",
2556
	     name, dev ? &dev->features : &null_features,
2557
	     skb->sk ? &skb->sk->sk_route_caps : &null_features,
2558 2559 2560 2561
	     skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
	     skb_shinfo(skb)->gso_type, skb->ip_summed);
}

L
Linus Torvalds 已提交
2562 2563 2564 2565
/*
 * Invalidate hardware checksum when packet is to be mangled, and
 * complete checksum manually on outgoing path.
 */
2566
int skb_checksum_help(struct sk_buff *skb)
L
Linus Torvalds 已提交
2567
{
2568
	__wsum csum;
2569
	int ret = 0, offset;
L
Linus Torvalds 已提交
2570

2571
	if (skb->ip_summed == CHECKSUM_COMPLETE)
2572 2573 2574
		goto out_set_summed;

	if (unlikely(skb_shinfo(skb)->gso_size)) {
2575 2576
		skb_warn_bad_offload(skb);
		return -EINVAL;
L
Linus Torvalds 已提交
2577 2578
	}

2579 2580 2581 2582 2583 2584 2585 2586 2587
	/* 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;
	}

2588
	offset = skb_checksum_start_offset(skb);
2589 2590 2591 2592 2593 2594 2595 2596
	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
2597 2598 2599 2600 2601
		ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
		if (ret)
			goto out;
	}

2602
	*(__sum16 *)(skb->data + offset) = csum_fold(csum);
2603
out_set_summed:
L
Linus Torvalds 已提交
2604
	skb->ip_summed = CHECKSUM_NONE;
2605
out:
L
Linus Torvalds 已提交
2606 2607
	return ret;
}
E
Eric Dumazet 已提交
2608
EXPORT_SYMBOL(skb_checksum_help);
L
Linus Torvalds 已提交
2609

2610
__be16 skb_network_protocol(struct sk_buff *skb, int *depth)
2611
{
A
Al Viro 已提交
2612
	__be16 type = skb->protocol;
2613

2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624
	/* 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;
	}

2625
	return __vlan_get_protocol(skb, type, depth);
2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637
}

/**
 *	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;
2638 2639
	int vlan_depth = skb->mac_len;
	__be16 type = skb_network_protocol(skb, &vlan_depth);
2640 2641 2642 2643

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

2644
	__skb_pull(skb, vlan_depth);
2645 2646

	rcu_read_lock();
2647
	list_for_each_entry_rcu(ptype, &offload_base, list) {
2648 2649
		if (ptype->type == type && ptype->callbacks.gso_segment) {
			segs = ptype->callbacks.gso_segment(skb, features);
2650 2651 2652 2653 2654
			break;
		}
	}
	rcu_read_unlock();

2655
	__skb_push(skb, skb->data - skb_mac_header(skb));
2656

2657 2658
	return segs;
}
2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681
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.
2682 2683
 *
 *	Segmentation preserves SKB_SGO_CB_OFFSET bytes of previous skb cb.
2684 2685 2686 2687 2688 2689 2690 2691 2692
 */
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);

2693 2694
		err = skb_cow_head(skb, 0);
		if (err < 0)
2695 2696 2697
			return ERR_PTR(err);
	}

2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710
	/* 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;
	}

2711 2712 2713
	BUILD_BUG_ON(SKB_SGO_CB_OFFSET +
		     sizeof(*SKB_GSO_CB(skb)) > sizeof(skb->cb));

2714
	SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
2715 2716
	SKB_GSO_CB(skb)->encap_level = 0;

2717 2718 2719 2720 2721
	skb_reset_mac_header(skb);
	skb_reset_mac_len(skb);

	return skb_mac_gso_segment(skb, features);
}
2722
EXPORT_SYMBOL(__skb_gso_segment);
2723

2724 2725 2726 2727 2728
/* Take action when hardware reception checksum errors are detected. */
#ifdef CONFIG_BUG
void netdev_rx_csum_fault(struct net_device *dev)
{
	if (net_ratelimit()) {
2729
		pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
2730 2731 2732 2733 2734 2735
		dump_stack();
	}
}
EXPORT_SYMBOL(netdev_rx_csum_fault);
#endif

L
Linus Torvalds 已提交
2736 2737 2738 2739 2740
/* 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.
 */

2741
static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
L
Linus Torvalds 已提交
2742
{
2743
#ifdef CONFIG_HIGHMEM
L
Linus Torvalds 已提交
2744
	int i;
2745
	if (!(dev->features & NETIF_F_HIGHDMA)) {
2746 2747 2748
		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)))
2749
				return 1;
2750
		}
2751
	}
L
Linus Torvalds 已提交
2752

2753 2754
	if (PCI_DMA_BUS_IS_PHYS) {
		struct device *pdev = dev->dev.parent;
L
Linus Torvalds 已提交
2755

E
Eric Dumazet 已提交
2756 2757
		if (!pdev)
			return 0;
2758
		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
2759 2760
			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
			dma_addr_t addr = page_to_phys(skb_frag_page(frag));
2761 2762 2763 2764
			if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
				return 1;
		}
	}
2765
#endif
L
Linus Torvalds 已提交
2766 2767 2768
	return 0;
}

2769 2770 2771
/* 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
2772
#if IS_ENABLED(CONFIG_NET_MPLS_GSO)
2773 2774 2775 2776
static netdev_features_t net_mpls_features(struct sk_buff *skb,
					   netdev_features_t features,
					   __be16 type)
{
2777
	if (eth_p_mpls(type))
2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790
		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

2791
static netdev_features_t harmonize_features(struct sk_buff *skb,
2792
	netdev_features_t features)
2793
{
2794
	int tmp;
2795 2796 2797 2798
	__be16 type;

	type = skb_network_protocol(skb, &tmp);
	features = net_mpls_features(skb, features, type);
2799

2800
	if (skb->ip_summed != CHECKSUM_NONE &&
2801
	    !can_checksum_protocol(features, type)) {
2802
		features &= ~(NETIF_F_CSUM_MASK | NETIF_F_GSO_MASK);
2803
	} else if (illegal_highdma(skb->dev, skb)) {
2804 2805 2806 2807 2808 2809
		features &= ~NETIF_F_SG;
	}

	return features;
}

2810 2811 2812 2813 2814 2815 2816 2817
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);

2818 2819 2820 2821 2822 2823 2824
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);
}

2825 2826 2827 2828 2829 2830 2831 2832 2833
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;

2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844
	/* 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.
2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856
	 */
	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;
}

2857
netdev_features_t netif_skb_features(struct sk_buff *skb)
2858
{
2859
	struct net_device *dev = skb->dev;
2860
	netdev_features_t features = dev->features;
2861

2862 2863
	if (skb_is_gso(skb))
		features = gso_features_check(skb, dev, features);
2864

2865 2866 2867 2868 2869 2870 2871
	/* 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;

2872 2873 2874 2875 2876
	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);
2877

2878 2879 2880
	if (dev->netdev_ops->ndo_features_check)
		features &= dev->netdev_ops->ndo_features_check(skb, dev,
								features);
2881 2882
	else
		features &= dflt_features_check(skb, dev, features);
2883

2884
	return harmonize_features(skb, features);
2885
}
2886
EXPORT_SYMBOL(netif_skb_features);
2887

2888
static int xmit_one(struct sk_buff *skb, struct net_device *dev,
2889
		    struct netdev_queue *txq, bool more)
2890
{
2891 2892
	unsigned int len;
	int rc;
2893

2894
	if (!list_empty(&ptype_all) || !list_empty(&dev->ptype_all))
2895
		dev_queue_xmit_nit(skb, dev);
2896

2897 2898
	len = skb->len;
	trace_net_dev_start_xmit(skb, dev);
2899
	rc = netdev_start_xmit(skb, dev, txq, more);
2900
	trace_net_dev_xmit(skb, rc, dev, len);
E
Eric Dumazet 已提交
2901

2902 2903
	return rc;
}
2904

2905 2906
struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev,
				    struct netdev_queue *txq, int *ret)
2907 2908 2909
{
	struct sk_buff *skb = first;
	int rc = NETDEV_TX_OK;
2910

2911 2912
	while (skb) {
		struct sk_buff *next = skb->next;
2913

2914
		skb->next = NULL;
2915
		rc = xmit_one(skb, dev, txq, next != NULL);
2916 2917 2918 2919
		if (unlikely(!dev_xmit_complete(rc))) {
			skb->next = next;
			goto out;
		}
2920

2921 2922 2923 2924
		skb = next;
		if (netif_xmit_stopped(txq) && skb) {
			rc = NETDEV_TX_BUSY;
			break;
2925
		}
2926
	}
2927

2928 2929 2930 2931
out:
	*ret = rc;
	return skb;
}
2932

E
Eric Dumazet 已提交
2933 2934
static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
					  netdev_features_t features)
2935
{
2936
	if (skb_vlan_tag_present(skb) &&
2937 2938
	    !vlan_hw_offload_capable(features, skb->vlan_proto))
		skb = __vlan_hwaccel_push_inside(skb);
2939 2940
	return skb;
}
2941

2942
static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev)
2943 2944
{
	netdev_features_t features;
2945

2946 2947 2948 2949
	features = netif_skb_features(skb);
	skb = validate_xmit_vlan(skb, features);
	if (unlikely(!skb))
		goto out_null;
2950

2951
	if (netif_needs_gso(skb, features)) {
2952 2953 2954
		struct sk_buff *segs;

		segs = skb_gso_segment(skb, features);
2955
		if (IS_ERR(segs)) {
2956
			goto out_kfree_skb;
2957 2958 2959
		} else if (segs) {
			consume_skb(skb);
			skb = segs;
2960
		}
2961 2962 2963 2964
	} else {
		if (skb_needs_linearize(skb, features) &&
		    __skb_linearize(skb))
			goto out_kfree_skb;
2965

2966 2967 2968 2969 2970 2971 2972 2973 2974 2975 2976
		/* 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));
2977
			if (!(features & NETIF_F_CSUM_MASK) &&
2978 2979
			    skb_checksum_help(skb))
				goto out_kfree_skb;
2980
		}
2981
	}
2982

2983
	return skb;
2984

2985 2986
out_kfree_skb:
	kfree_skb(skb);
2987
out_null:
E
Eric Dumazet 已提交
2988
	atomic_long_inc(&dev->tx_dropped);
2989 2990
	return NULL;
}
2991

2992 2993 2994 2995
struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev)
{
	struct sk_buff *next, *head = NULL, *tail;

2996
	for (; skb != NULL; skb = next) {
2997 2998
		next = skb->next;
		skb->next = NULL;
2999 3000 3001 3002

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

3003
		skb = validate_xmit_skb(skb, dev);
3004 3005
		if (!skb)
			continue;
3006

3007 3008 3009 3010 3011 3012 3013 3014
		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;
3015 3016
	}
	return head;
3017
}
3018
EXPORT_SYMBOL_GPL(validate_xmit_skb_list);
3019

3020 3021 3022 3023 3024 3025 3026 3027 3028 3029
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)  {
3030
		unsigned int hdr_len;
3031
		u16 gso_segs = shinfo->gso_segs;
3032

3033 3034 3035 3036
		/* mac layer + network layer */
		hdr_len = skb_transport_header(skb) - skb_mac_header(skb);

		/* + transport layer */
3037 3038 3039 3040
		if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
			hdr_len += tcp_hdrlen(skb);
		else
			hdr_len += sizeof(struct udphdr);
3041 3042 3043 3044 3045 3046

		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;
3047 3048 3049
	}
}

3050 3051 3052 3053 3054
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);
3055
	struct sk_buff *to_free = NULL;
E
Eric Dumazet 已提交
3056
	bool contended;
3057 3058
	int rc;

E
Eric Dumazet 已提交
3059
	qdisc_calculate_pkt_len(skb, q);
3060 3061 3062
	/*
	 * Heuristic to force contended enqueues to serialize on a
	 * separate lock before trying to get qdisc main lock.
3063
	 * This permits qdisc->running owner to get the lock more
Y
Ying Xue 已提交
3064
	 * often and dequeue packets faster.
3065
	 */
E
Eric Dumazet 已提交
3066
	contended = qdisc_is_running(q);
3067 3068 3069
	if (unlikely(contended))
		spin_lock(&q->busylock);

3070 3071
	spin_lock(root_lock);
	if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
3072
		__qdisc_drop(skb, &to_free);
3073 3074
		rc = NET_XMIT_DROP;
	} else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
3075
		   qdisc_run_begin(q)) {
3076 3077 3078 3079 3080
		/*
		 * 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.
		 */
3081 3082 3083

		qdisc_bstats_update(q, skb);

3084
		if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) {
3085 3086 3087 3088
			if (unlikely(contended)) {
				spin_unlock(&q->busylock);
				contended = false;
			}
3089
			__qdisc_run(q);
3090
		} else
3091
			qdisc_run_end(q);
3092 3093 3094

		rc = NET_XMIT_SUCCESS;
	} else {
3095
		rc = q->enqueue(skb, q, &to_free) & NET_XMIT_MASK;
3096 3097 3098 3099 3100 3101 3102
		if (qdisc_run_begin(q)) {
			if (unlikely(contended)) {
				spin_unlock(&q->busylock);
				contended = false;
			}
			__qdisc_run(q);
		}
3103 3104
	}
	spin_unlock(root_lock);
3105 3106
	if (unlikely(to_free))
		kfree_skb_list(to_free);
3107 3108
	if (unlikely(contended))
		spin_unlock(&q->busylock);
3109 3110 3111
	return rc;
}

3112
#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
3113 3114
static void skb_update_prio(struct sk_buff *skb)
{
I
Igor Maravic 已提交
3115
	struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
3116

3117
	if (!skb->priority && skb->sk && map) {
3118 3119
		unsigned int prioidx =
			sock_cgroup_prioidx(&skb->sk->sk_cgrp_data);
3120 3121 3122 3123

		if (prioidx < map->priomap_len)
			skb->priority = map->priomap[prioidx];
	}
3124 3125 3126 3127 3128
}
#else
#define skb_update_prio(skb)
#endif

3129 3130 3131
DEFINE_PER_CPU(int, xmit_recursion);
EXPORT_SYMBOL(xmit_recursion);

3132 3133
/**
 *	dev_loopback_xmit - loop back @skb
3134 3135
 *	@net: network namespace this loopback is happening in
 *	@sk:  sk needed to be a netfilter okfn
3136 3137
 *	@skb: buffer to transmit
 */
3138
int dev_loopback_xmit(struct net *net, struct sock *sk, struct sk_buff *skb)
3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150
{
	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
3151 3152 3153 3154 3155 3156 3157 3158 3159 3160 3161 3162 3163 3164 3165 3166 3167 3168 3169 3170 3171 3172 3173
#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;
3174 3175
		kfree_skb(skb);
		return NULL;
D
Daniel Borkmann 已提交
3176 3177 3178
	case TC_ACT_STOLEN:
	case TC_ACT_QUEUED:
		*ret = NET_XMIT_SUCCESS;
3179
		consume_skb(skb);
D
Daniel Borkmann 已提交
3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193
		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 */

3194 3195 3196 3197 3198 3199 3200 3201 3202 3203
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) {
3204 3205 3206 3207 3208 3209 3210 3211
		unsigned int tci = skb->sender_cpu - 1;

		if (dev->num_tc) {
			tci *= dev->num_tc;
			tci += netdev_get_prio_tc_map(dev, skb->priority);
		}

		map = rcu_dereference(dev_maps->cpu_map[tci]);
3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236 3237 3238 3239 3240 3241
		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 &&
3242
		    sk_fullsock(sk) &&
3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258
		    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
3259 3260 3261
	u32 sender_cpu = skb->sender_cpu - 1;

	if (sender_cpu >= (u32)NR_CPUS)
3262 3263 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280
		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);
}

3281
/**
3282
 *	__dev_queue_xmit - transmit a buffer
3283
 *	@skb: buffer to transmit
3284
 *	@accel_priv: private data used for L2 forwarding offload
3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306
 *
 *	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
 */
3307
static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
L
Linus Torvalds 已提交
3308 3309
{
	struct net_device *dev = skb->dev;
3310
	struct netdev_queue *txq;
L
Linus Torvalds 已提交
3311 3312 3313
	struct Qdisc *q;
	int rc = -ENOMEM;

3314 3315
	skb_reset_mac_header(skb);

3316 3317 3318
	if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
		__skb_tstamp_tx(skb, NULL, skb->sk, SCM_TSTAMP_SCHED);

3319 3320
	/* Disable soft irqs for various locks below. Also
	 * stops preemption for RCU.
L
Linus Torvalds 已提交
3321
	 */
3322
	rcu_read_lock_bh();
L
Linus Torvalds 已提交
3323

3324 3325
	skb_update_prio(skb);

D
Daniel Borkmann 已提交
3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336
	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
3337 3338 3339 3340 3341 3342 3343 3344
	/* 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);

3345
	txq = netdev_pick_tx(dev, skb, accel_priv);
3346
	q = rcu_dereference_bh(txq->qdisc);
3347

3348
	trace_net_dev_queue(skb);
L
Linus Torvalds 已提交
3349
	if (q->enqueue) {
3350
		rc = __dev_xmit_skb(skb, q, dev, txq);
3351
		goto out;
L
Linus Torvalds 已提交
3352 3353 3354 3355 3356
	}

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

H
Herbert Xu 已提交
3357 3358
	   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
3359 3360 3361 3362 3363 3364 3365 3366 3367 3368
	   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 */

3369
		if (txq->xmit_lock_owner != cpu) {
3370 3371
			if (unlikely(__this_cpu_read(xmit_recursion) >
				     XMIT_RECURSION_LIMIT))
3372 3373
				goto recursion_alert;

3374 3375
			skb = validate_xmit_skb(skb, dev);
			if (!skb)
E
Eric Dumazet 已提交
3376
				goto out;
3377

3378
			HARD_TX_LOCK(dev, txq, cpu);
L
Linus Torvalds 已提交
3379

3380
			if (!netif_xmit_stopped(txq)) {
3381
				__this_cpu_inc(xmit_recursion);
3382
				skb = dev_hard_start_xmit(skb, dev, txq, &rc);
3383
				__this_cpu_dec(xmit_recursion);
3384
				if (dev_xmit_complete(rc)) {
3385
					HARD_TX_UNLOCK(dev, txq);
L
Linus Torvalds 已提交
3386 3387 3388
					goto out;
				}
			}
3389
			HARD_TX_UNLOCK(dev, txq);
3390 3391
			net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
					     dev->name);
L
Linus Torvalds 已提交
3392 3393
		} else {
			/* Recursion is detected! It is possible,
3394 3395 3396
			 * unfortunately
			 */
recursion_alert:
3397 3398
			net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
					     dev->name);
L
Linus Torvalds 已提交
3399 3400 3401 3402
		}
	}

	rc = -ENETDOWN;
3403
	rcu_read_unlock_bh();
L
Linus Torvalds 已提交
3404

3405
	atomic_long_inc(&dev->tx_dropped);
3406
	kfree_skb_list(skb);
L
Linus Torvalds 已提交
3407 3408
	return rc;
out:
3409
	rcu_read_unlock_bh();
L
Linus Torvalds 已提交
3410 3411
	return rc;
}
3412

3413
int dev_queue_xmit(struct sk_buff *skb)
3414 3415 3416
{
	return __dev_queue_xmit(skb, NULL);
}
3417
EXPORT_SYMBOL(dev_queue_xmit);
L
Linus Torvalds 已提交
3418

3419 3420 3421 3422 3423 3424
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
3425 3426 3427 3428 3429

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

3430
int netdev_max_backlog __read_mostly = 1000;
E
Eric Dumazet 已提交
3431 3432
EXPORT_SYMBOL(netdev_max_backlog);

E
Eric Dumazet 已提交
3433
int netdev_tstamp_prequeue __read_mostly = 1;
3434 3435
int netdev_budget __read_mostly = 300;
int weight_p __read_mostly = 64;            /* old backlog weight */
L
Linus Torvalds 已提交
3436

E
Eric Dumazet 已提交
3437 3438 3439 3440 3441 3442 3443 3444
/* 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);
}

3445 3446 3447
#ifdef CONFIG_RPS

/* One global table that all flow-based protocols share. */
E
Eric Dumazet 已提交
3448
struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
3449
EXPORT_SYMBOL(rps_sock_flow_table);
3450 3451
u32 rps_cpu_mask __read_mostly;
EXPORT_SYMBOL(rps_cpu_mask);
3452

3453
struct static_key rps_needed __read_mostly;
3454
EXPORT_SYMBOL(rps_needed);
3455

3456 3457 3458 3459
static struct rps_dev_flow *
set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
	    struct rps_dev_flow *rflow, u16 next_cpu)
{
3460
	if (next_cpu < nr_cpu_ids) {
3461 3462 3463 3464 3465 3466 3467 3468 3469
#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? */
3470 3471
		if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
		    !(dev->features & NETIF_F_NTUPLE))
3472 3473 3474 3475 3476 3477 3478 3479 3480
			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;
3481
		flow_id = skb_get_hash(skb) & flow_table->mask;
3482 3483 3484 3485 3486 3487 3488 3489 3490 3491 3492 3493
		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 =
3494
			per_cpu(softnet_data, next_cpu).input_queue_head;
3495 3496
	}

3497
	rflow->cpu = next_cpu;
3498 3499 3500
	return rflow;
}

3501 3502 3503 3504 3505 3506 3507 3508
/*
 * 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)
{
3509 3510
	const struct rps_sock_flow_table *sock_flow_table;
	struct netdev_rx_queue *rxqueue = dev->_rx;
3511
	struct rps_dev_flow_table *flow_table;
3512
	struct rps_map *map;
3513
	int cpu = -1;
3514
	u32 tcpu;
3515
	u32 hash;
3516 3517 3518

	if (skb_rx_queue_recorded(skb)) {
		u16 index = skb_get_rx_queue(skb);
3519

3520 3521 3522 3523 3524
		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);
3525 3526
			goto done;
		}
3527 3528
		rxqueue += index;
	}
3529

3530 3531 3532
	/* 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
3533
	map = rcu_dereference(rxqueue->rps_map);
3534
	if (!flow_table && !map)
3535 3536
		goto done;

3537
	skb_reset_network_header(skb);
3538 3539
	hash = skb_get_hash(skb);
	if (!hash)
3540 3541
		goto done;

T
Tom Herbert 已提交
3542 3543 3544
	sock_flow_table = rcu_dereference(rps_sock_flow_table);
	if (flow_table && sock_flow_table) {
		struct rps_dev_flow *rflow;
3545 3546 3547 3548 3549 3550 3551
		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
3552

3553 3554 3555 3556 3557
		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
		 */
3558
		rflow = &flow_table->flows[hash & flow_table->mask];
T
Tom Herbert 已提交
3559 3560 3561 3562 3563 3564
		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:
3565
		 *   - Current CPU is unset (>= nr_cpu_ids).
T
Tom Herbert 已提交
3566 3567 3568 3569 3570 3571 3572
		 *   - 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) &&
3573
		    (tcpu >= nr_cpu_ids || !cpu_online(tcpu) ||
T
Tom Herbert 已提交
3574
		     ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
3575 3576
		      rflow->last_qtail)) >= 0)) {
			tcpu = next_cpu;
3577
			rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
3578
		}
3579

3580
		if (tcpu < nr_cpu_ids && cpu_online(tcpu)) {
T
Tom Herbert 已提交
3581 3582 3583 3584 3585 3586
			*rflowp = rflow;
			cpu = tcpu;
			goto done;
		}
	}

3587 3588
try_rps:

T
Tom Herbert 已提交
3589
	if (map) {
3590
		tcpu = map->cpus[reciprocal_scale(hash, map->len)];
T
Tom Herbert 已提交
3591 3592 3593 3594 3595 3596 3597 3598 3599 3600
		if (cpu_online(tcpu)) {
			cpu = tcpu;
			goto done;
		}
	}

done:
	return cpu;
}

3601 3602 3603 3604 3605 3606 3607 3608 3609 3610 3611 3612 3613 3614 3615 3616 3617 3618 3619 3620
#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;
3621
	unsigned int cpu;
3622 3623 3624 3625 3626 3627

	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);
3628
		if (rflow->filter == filter_id && cpu < nr_cpu_ids &&
3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640
		    ((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
3641
/* Called from hardirq (IPI) context */
E
Eric Dumazet 已提交
3642
static void rps_trigger_softirq(void *data)
T
Tom Herbert 已提交
3643
{
E
Eric Dumazet 已提交
3644 3645
	struct softnet_data *sd = data;

E
Eric Dumazet 已提交
3646
	____napi_schedule(sd, &sd->backlog);
C
Changli Gao 已提交
3647
	sd->received_rps++;
T
Tom Herbert 已提交
3648
}
E
Eric Dumazet 已提交
3649

T
Tom Herbert 已提交
3650
#endif /* CONFIG_RPS */
T
Tom Herbert 已提交
3651

E
Eric Dumazet 已提交
3652 3653 3654 3655 3656 3657 3658 3659
/*
 * 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
3660
	struct softnet_data *mysd = this_cpu_ptr(&softnet_data);
E
Eric Dumazet 已提交
3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672

	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;
}

3673 3674 3675 3676 3677 3678 3679 3680 3681 3682 3683 3684 3685 3686
#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;

3687
	sd = this_cpu_ptr(&softnet_data);
3688 3689 3690 3691

	rcu_read_lock();
	fl = rcu_dereference(sd->flow_limit);
	if (fl) {
3692
		new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
3693 3694 3695 3696 3697 3698 3699 3700 3701 3702 3703 3704 3705 3706 3707 3708 3709 3710 3711 3712
		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
3713 3714 3715 3716
/*
 * 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
3717 3718
static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
			      unsigned int *qtail)
T
Tom Herbert 已提交
3719
{
E
Eric Dumazet 已提交
3720
	struct softnet_data *sd;
T
Tom Herbert 已提交
3721
	unsigned long flags;
3722
	unsigned int qlen;
T
Tom Herbert 已提交
3723

E
Eric Dumazet 已提交
3724
	sd = &per_cpu(softnet_data, cpu);
T
Tom Herbert 已提交
3725 3726 3727

	local_irq_save(flags);

E
Eric Dumazet 已提交
3728
	rps_lock(sd);
3729 3730
	if (!netif_running(skb->dev))
		goto drop;
3731 3732
	qlen = skb_queue_len(&sd->input_pkt_queue);
	if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
3733
		if (qlen) {
T
Tom Herbert 已提交
3734
enqueue:
E
Eric Dumazet 已提交
3735
			__skb_queue_tail(&sd->input_pkt_queue, skb);
3736
			input_queue_tail_incr_save(sd, qtail);
E
Eric Dumazet 已提交
3737
			rps_unlock(sd);
3738
			local_irq_restore(flags);
T
Tom Herbert 已提交
3739 3740 3741
			return NET_RX_SUCCESS;
		}

3742 3743 3744 3745
		/* 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
3746
			if (!rps_ipi_queued(sd))
E
Eric Dumazet 已提交
3747
				____napi_schedule(sd, &sd->backlog);
T
Tom Herbert 已提交
3748 3749 3750 3751
		}
		goto enqueue;
	}

3752
drop:
C
Changli Gao 已提交
3753
	sd->dropped++;
E
Eric Dumazet 已提交
3754
	rps_unlock(sd);
T
Tom Herbert 已提交
3755 3756 3757

	local_irq_restore(flags);

3758
	atomic_long_inc(&skb->dev->rx_dropped);
T
Tom Herbert 已提交
3759 3760 3761
	kfree_skb(skb);
	return NET_RX_DROP;
}
L
Linus Torvalds 已提交
3762

3763
static int netif_rx_internal(struct sk_buff *skb)
L
Linus Torvalds 已提交
3764
{
3765
	int ret;
L
Linus Torvalds 已提交
3766

3767
	net_timestamp_check(netdev_tstamp_prequeue, skb);
L
Linus Torvalds 已提交
3768

3769
	trace_netif_rx(skb);
E
Eric Dumazet 已提交
3770
#ifdef CONFIG_RPS
3771
	if (static_key_false(&rps_needed)) {
T
Tom Herbert 已提交
3772
		struct rps_dev_flow voidflow, *rflow = &voidflow;
3773 3774
		int cpu;

3775
		preempt_disable();
3776
		rcu_read_lock();
T
Tom Herbert 已提交
3777 3778

		cpu = get_rps_cpu(skb->dev, skb, &rflow);
3779 3780
		if (cpu < 0)
			cpu = smp_processor_id();
T
Tom Herbert 已提交
3781 3782 3783

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

3784
		rcu_read_unlock();
3785
		preempt_enable();
3786 3787
	} else
#endif
T
Tom Herbert 已提交
3788 3789 3790 3791 3792
	{
		unsigned int qtail;
		ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
		put_cpu();
	}
3793
	return ret;
L
Linus Torvalds 已提交
3794
}
3795 3796 3797 3798 3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811 3812 3813 3814 3815 3816

/**
 *	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
3817
EXPORT_SYMBOL(netif_rx);
L
Linus Torvalds 已提交
3818 3819 3820 3821 3822

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

3823 3824
	trace_netif_rx_ni_entry(skb);

L
Linus Torvalds 已提交
3825
	preempt_disable();
3826
	err = netif_rx_internal(skb);
L
Linus Torvalds 已提交
3827 3828 3829 3830 3831 3832 3833 3834
	if (local_softirq_pending())
		do_softirq();
	preempt_enable();

	return err;
}
EXPORT_SYMBOL(netif_rx_ni);

3835
static __latent_entropy void net_tx_action(struct softirq_action *h)
L
Linus Torvalds 已提交
3836
{
3837
	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
L
Linus Torvalds 已提交
3838 3839 3840 3841 3842 3843 3844 3845 3846 3847 3848 3849 3850

	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;

3851
			WARN_ON(atomic_read(&skb->users));
3852 3853 3854 3855
			if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
				trace_consume_skb(skb);
			else
				trace_kfree_skb(skb, net_tx_action);
3856 3857 3858 3859 3860

			if (skb->fclone != SKB_FCLONE_UNAVAILABLE)
				__kfree_skb(skb);
			else
				__kfree_skb_defer(skb);
L
Linus Torvalds 已提交
3861
		}
3862 3863

		__kfree_skb_flush();
L
Linus Torvalds 已提交
3864 3865 3866
	}

	if (sd->output_queue) {
3867
		struct Qdisc *head;
L
Linus Torvalds 已提交
3868 3869 3870 3871

		local_irq_disable();
		head = sd->output_queue;
		sd->output_queue = NULL;
3872
		sd->output_queue_tailp = &sd->output_queue;
L
Linus Torvalds 已提交
3873 3874 3875
		local_irq_enable();

		while (head) {
3876 3877 3878
			struct Qdisc *q = head;
			spinlock_t *root_lock;

L
Linus Torvalds 已提交
3879 3880
			head = head->next_sched;

3881
			root_lock = qdisc_lock(q);
3882 3883 3884 3885 3886 3887 3888 3889
			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
3890 3891 3892 3893
		}
	}
}

3894
#if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_ATM_LANE)
3895 3896 3897
/* This hook is defined here for ATM LANE */
int (*br_fdb_test_addr_hook)(struct net_device *dev,
			     unsigned char *addr) __read_mostly;
3898
EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
3899
#endif
L
Linus Torvalds 已提交
3900

D
Daniel Borkmann 已提交
3901 3902 3903
static inline struct sk_buff *
sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret,
		   struct net_device *orig_dev)
3904
{
3905
#ifdef CONFIG_NET_CLS_ACT
3906 3907
	struct tcf_proto *cl = rcu_dereference_bh(skb->dev->ingress_cl_list);
	struct tcf_result cl_res;
3908

3909 3910 3911
	/* 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
3912
	 * out here.
3913
	 */
3914
	if (!cl)
3915
		return skb;
3916 3917 3918
	if (*pt_prev) {
		*ret = deliver_skb(skb, *pt_prev, orig_dev);
		*pt_prev = NULL;
L
Linus Torvalds 已提交
3919 3920
	}

3921
	qdisc_skb_cb(skb)->pkt_len = skb->len;
3922
	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
3923
	qdisc_bstats_cpu_update(cl->q, skb);
3924

3925
	switch (tc_classify(skb, cl, &cl_res, false)) {
3926 3927 3928 3929 3930
	case TC_ACT_OK:
	case TC_ACT_RECLASSIFY:
		skb->tc_index = TC_H_MIN(cl_res.classid);
		break;
	case TC_ACT_SHOT:
3931
		qdisc_qstats_cpu_drop(cl->q);
3932 3933
		kfree_skb(skb);
		return NULL;
3934 3935
	case TC_ACT_STOLEN:
	case TC_ACT_QUEUED:
3936
		consume_skb(skb);
3937
		return NULL;
3938 3939 3940 3941 3942 3943 3944 3945
	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;
3946 3947
	default:
		break;
3948
	}
3949
#endif /* CONFIG_NET_CLS_ACT */
3950 3951
	return skb;
}
L
Linus Torvalds 已提交
3952

M
Mahesh Bandewar 已提交
3953 3954 3955 3956 3957 3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968
/**
 *	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);

3969 3970 3971 3972
/**
 *	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
3973
 *	@rx_handler_data: data pointer that is used by rx handler
3974
 *
3975
 *	Register a receive handler for a device. This handler will then be
3976 3977 3978 3979
 *	called from __netif_receive_skb. A negative errno code is returned
 *	on a failure.
 *
 *	The caller must hold the rtnl_mutex.
3980 3981
 *
 *	For a general description of rx_handler, see enum rx_handler_result.
3982 3983
 */
int netdev_rx_handler_register(struct net_device *dev,
J
Jiri Pirko 已提交
3984 3985
			       rx_handler_func_t *rx_handler,
			       void *rx_handler_data)
3986 3987 3988 3989 3990 3991
{
	ASSERT_RTNL();

	if (dev->rx_handler)
		return -EBUSY;

3992
	/* Note: rx_handler_data must be set before rx_handler */
J
Jiri Pirko 已提交
3993
	rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
3994 3995 3996 3997 3998 3999 4000 4001 4002 4003
	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
4004
 *	Unregister a receive handler from a device.
4005 4006 4007 4008 4009 4010 4011
 *
 *	The caller must hold the rtnl_mutex.
 */
void netdev_rx_handler_unregister(struct net_device *dev)
{

	ASSERT_RTNL();
4012
	RCU_INIT_POINTER(dev->rx_handler, NULL);
4013 4014 4015 4016 4017
	/* 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();
4018
	RCU_INIT_POINTER(dev->rx_handler_data, NULL);
4019 4020 4021
}
EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);

4022 4023 4024 4025 4026 4027 4028
/*
 * 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) {
4029 4030 4031 4032 4033
	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):
4034 4035 4036 4037 4038 4039
		return true;
	default:
		return false;
	}
}

4040 4041 4042
static inline int nf_ingress(struct sk_buff *skb, struct packet_type **pt_prev,
			     int *ret, struct net_device *orig_dev)
{
4043
#ifdef CONFIG_NETFILTER_INGRESS
4044
	if (nf_hook_ingress_active(skb)) {
4045 4046
		int ingress_retval;

4047 4048 4049 4050 4051
		if (*pt_prev) {
			*ret = deliver_skb(skb, *pt_prev, orig_dev);
			*pt_prev = NULL;
		}

4052 4053 4054 4055
		rcu_read_lock();
		ingress_retval = nf_hook_ingress(skb);
		rcu_read_unlock();
		return ingress_retval;
4056
	}
4057
#endif /* CONFIG_NETFILTER_INGRESS */
4058 4059 4060
	return 0;
}

4061
static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
L
Linus Torvalds 已提交
4062 4063
{
	struct packet_type *ptype, *pt_prev;
4064
	rx_handler_func_t *rx_handler;
D
David S. Miller 已提交
4065
	struct net_device *orig_dev;
4066
	bool deliver_exact = false;
L
Linus Torvalds 已提交
4067
	int ret = NET_RX_DROP;
A
Al Viro 已提交
4068
	__be16 type;
L
Linus Torvalds 已提交
4069

4070
	net_timestamp_check(!netdev_tstamp_prequeue, skb);
4071

4072
	trace_netif_receive_skb(skb);
4073

J
Joe Eykholt 已提交
4074
	orig_dev = skb->dev;
4075

4076
	skb_reset_network_header(skb);
4077 4078
	if (!skb_transport_header_was_set(skb))
		skb_reset_transport_header(skb);
4079
	skb_reset_mac_len(skb);
L
Linus Torvalds 已提交
4080 4081 4082

	pt_prev = NULL;

4083
another_round:
4084
	skb->skb_iif = skb->dev->ifindex;
4085 4086 4087

	__this_cpu_inc(softnet_data.processed);

P
Patrick McHardy 已提交
4088 4089
	if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
	    skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
4090
		skb = skb_vlan_untag(skb);
4091
		if (unlikely(!skb))
4092
			goto out;
4093 4094
	}

L
Linus Torvalds 已提交
4095 4096 4097 4098 4099 4100 4101
#ifdef CONFIG_NET_CLS_ACT
	if (skb->tc_verd & TC_NCLS) {
		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
		goto ncls;
	}
#endif

4102
	if (pfmemalloc)
4103 4104
		goto skip_taps;

L
Linus Torvalds 已提交
4105
	list_for_each_entry_rcu(ptype, &ptype_all, list) {
4106 4107 4108 4109 4110 4111 4112 4113 4114
		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
4115 4116
	}

4117
skip_taps:
4118
#ifdef CONFIG_NET_INGRESS
4119
	if (static_key_false(&ingress_needed)) {
D
Daniel Borkmann 已提交
4120
		skb = sch_handle_ingress(skb, &pt_prev, &ret, orig_dev);
4121
		if (!skb)
4122
			goto out;
4123 4124

		if (nf_ingress(skb, &pt_prev, &ret, orig_dev) < 0)
4125
			goto out;
4126
	}
4127 4128
#endif
#ifdef CONFIG_NET_CLS_ACT
4129
	skb->tc_verd = 0;
L
Linus Torvalds 已提交
4130 4131
ncls:
#endif
4132
	if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
4133 4134
		goto drop;

4135
	if (skb_vlan_tag_present(skb)) {
4136 4137 4138 4139
		if (pt_prev) {
			ret = deliver_skb(skb, pt_prev, orig_dev);
			pt_prev = NULL;
		}
4140
		if (vlan_do_receive(&skb))
4141 4142
			goto another_round;
		else if (unlikely(!skb))
4143
			goto out;
4144 4145
	}

4146
	rx_handler = rcu_dereference(skb->dev->rx_handler);
4147 4148 4149 4150 4151
	if (rx_handler) {
		if (pt_prev) {
			ret = deliver_skb(skb, pt_prev, orig_dev);
			pt_prev = NULL;
		}
4152 4153
		switch (rx_handler(&skb)) {
		case RX_HANDLER_CONSUMED:
4154
			ret = NET_RX_SUCCESS;
4155
			goto out;
4156
		case RX_HANDLER_ANOTHER:
4157
			goto another_round;
4158 4159 4160 4161 4162 4163 4164
		case RX_HANDLER_EXACT:
			deliver_exact = true;
		case RX_HANDLER_PASS:
			break;
		default:
			BUG();
		}
4165
	}
L
Linus Torvalds 已提交
4166

4167 4168
	if (unlikely(skb_vlan_tag_present(skb))) {
		if (skb_vlan_tag_get_id(skb))
E
Eric Dumazet 已提交
4169 4170 4171 4172 4173 4174 4175
			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;
	}
4176

4177 4178
	type = skb->protocol;

4179
	/* deliver only exact match when indicated */
4180 4181 4182 4183 4184
	if (likely(!deliver_exact)) {
		deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
				       &ptype_base[ntohs(type) &
						   PTYPE_HASH_MASK]);
	}
4185

4186 4187 4188 4189 4190 4191
	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
4192 4193 4194
	}

	if (pt_prev) {
4195
		if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
4196
			goto drop;
4197 4198
		else
			ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
L
Linus Torvalds 已提交
4199
	} else {
4200
drop:
4201 4202 4203 4204
		if (!deliver_exact)
			atomic_long_inc(&skb->dev->rx_dropped);
		else
			atomic_long_inc(&skb->dev->rx_nohandler);
L
Linus Torvalds 已提交
4205 4206 4207 4208 4209 4210 4211
		kfree_skb(skb);
		/* Jamal, now you will not able to escape explaining
		 * me how you were going to use this. :-)
		 */
		ret = NET_RX_DROP;
	}

4212
out:
4213 4214 4215 4216 4217 4218 4219 4220 4221 4222 4223 4224 4225 4226 4227 4228 4229 4230 4231 4232 4233 4234 4235 4236 4237
	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
4238 4239
	return ret;
}
T
Tom Herbert 已提交
4240

4241
static int netif_receive_skb_internal(struct sk_buff *skb)
T
Tom Herbert 已提交
4242
{
4243 4244
	int ret;

4245
	net_timestamp_check(netdev_tstamp_prequeue, skb);
E
Eric Dumazet 已提交
4246

4247 4248 4249
	if (skb_defer_rx_timestamp(skb))
		return NET_RX_SUCCESS;

4250 4251
	rcu_read_lock();

E
Eric Dumazet 已提交
4252
#ifdef CONFIG_RPS
4253
	if (static_key_false(&rps_needed)) {
E
Eric Dumazet 已提交
4254
		struct rps_dev_flow voidflow, *rflow = &voidflow;
4255
		int cpu = get_rps_cpu(skb->dev, skb, &rflow);
T
Tom Herbert 已提交
4256

E
Eric Dumazet 已提交
4257 4258 4259
		if (cpu >= 0) {
			ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
			rcu_read_unlock();
4260
			return ret;
E
Eric Dumazet 已提交
4261
		}
T
Tom Herbert 已提交
4262
	}
4263
#endif
4264 4265 4266
	ret = __netif_receive_skb(skb);
	rcu_read_unlock();
	return ret;
T
Tom Herbert 已提交
4267
}
4268 4269 4270 4271 4272 4273 4274 4275 4276 4277 4278 4279 4280 4281 4282 4283

/**
 *	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
 */
4284
int netif_receive_skb(struct sk_buff *skb)
4285 4286 4287 4288 4289
{
	trace_netif_receive_skb_entry(skb);

	return netif_receive_skb_internal(skb);
}
4290
EXPORT_SYMBOL(netif_receive_skb);
L
Linus Torvalds 已提交
4291

4292
DEFINE_PER_CPU(struct work_struct, flush_works);
4293 4294 4295

/* Network device is going away, flush any packets still pending */
static void flush_backlog(struct work_struct *work)
4296 4297
{
	struct sk_buff *skb, *tmp;
4298 4299 4300 4301
	struct softnet_data *sd;

	local_bh_disable();
	sd = this_cpu_ptr(&softnet_data);
4302

4303
	local_irq_disable();
E
Eric Dumazet 已提交
4304
	rps_lock(sd);
4305
	skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
4306
		if (skb->dev->reg_state == NETREG_UNREGISTERING) {
E
Eric Dumazet 已提交
4307
			__skb_unlink(skb, &sd->input_pkt_queue);
4308
			kfree_skb(skb);
4309
			input_queue_head_incr(sd);
4310
		}
4311
	}
E
Eric Dumazet 已提交
4312
	rps_unlock(sd);
4313
	local_irq_enable();
4314 4315

	skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
4316
		if (skb->dev->reg_state == NETREG_UNREGISTERING) {
4317 4318
			__skb_unlink(skb, &sd->process_queue);
			kfree_skb(skb);
4319
			input_queue_head_incr(sd);
4320 4321
		}
	}
4322 4323 4324
	local_bh_enable();
}

4325
static void flush_all_backlogs(void)
4326 4327 4328 4329 4330
{
	unsigned int cpu;

	get_online_cpus();

4331 4332 4333
	for_each_online_cpu(cpu)
		queue_work_on(cpu, system_highpri_wq,
			      per_cpu_ptr(&flush_works, cpu));
4334 4335

	for_each_online_cpu(cpu)
4336
		flush_work(per_cpu_ptr(&flush_works, cpu));
4337 4338

	put_online_cpus();
4339 4340
}

4341 4342
static int napi_gro_complete(struct sk_buff *skb)
{
4343
	struct packet_offload *ptype;
4344
	__be16 type = skb->protocol;
4345
	struct list_head *head = &offload_base;
4346 4347
	int err = -ENOENT;

4348 4349
	BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));

4350 4351
	if (NAPI_GRO_CB(skb)->count == 1) {
		skb_shinfo(skb)->gso_size = 0;
4352
		goto out;
4353
	}
4354 4355 4356

	rcu_read_lock();
	list_for_each_entry_rcu(ptype, head, list) {
4357
		if (ptype->type != type || !ptype->callbacks.gro_complete)
4358 4359
			continue;

4360
		err = ptype->callbacks.gro_complete(skb, 0);
4361 4362 4363 4364 4365 4366 4367 4368 4369 4370 4371
		break;
	}
	rcu_read_unlock();

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

out:
4372
	return netif_receive_skb_internal(skb);
4373 4374
}

4375 4376 4377 4378 4379
/* 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)
4380
{
4381
	struct sk_buff *skb, *prev = NULL;
4382

4383 4384 4385 4386 4387 4388 4389
	/* 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) {
4390
		skb->next = NULL;
4391 4392 4393 4394 4395

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

		prev = skb->prev;
4396
		napi_gro_complete(skb);
4397
		napi->gro_count--;
4398 4399 4400 4401
	}

	napi->gro_list = NULL;
}
E
Eric Dumazet 已提交
4402
EXPORT_SYMBOL(napi_gro_flush);
4403

E
Eric Dumazet 已提交
4404 4405 4406 4407
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;
4408
	u32 hash = skb_get_hash_raw(skb);
E
Eric Dumazet 已提交
4409 4410 4411 4412

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

4413 4414 4415 4416 4417 4418 4419
		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
4420 4421
		diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
		diffs |= p->vlan_tci ^ skb->vlan_tci;
4422
		diffs |= skb_metadata_dst_cmp(p, skb);
E
Eric Dumazet 已提交
4423 4424
		if (maclen == ETH_HLEN)
			diffs |= compare_ether_header(skb_mac_header(p),
4425
						      skb_mac_header(skb));
E
Eric Dumazet 已提交
4426 4427
		else if (!diffs)
			diffs = memcmp(skb_mac_header(p),
4428
				       skb_mac_header(skb),
E
Eric Dumazet 已提交
4429 4430 4431 4432 4433
				       maclen);
		NAPI_GRO_CB(p)->same_flow = !diffs;
	}
}

4434 4435 4436 4437 4438 4439 4440 4441 4442 4443 4444 4445 4446 4447
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
4448 4449 4450
	}
}

4451 4452 4453 4454 4455 4456 4457 4458 4459 4460 4461 4462 4463 4464 4465 4466 4467 4468 4469 4470 4471
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
4472
static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4473 4474
{
	struct sk_buff **pp = NULL;
4475
	struct packet_offload *ptype;
4476
	__be16 type = skb->protocol;
4477
	struct list_head *head = &offload_base;
H
Herbert Xu 已提交
4478
	int same_flow;
4479
	enum gro_result ret;
4480
	int grow;
4481

4482
	if (!(skb->dev->features & NETIF_F_GRO))
4483 4484
		goto normal;

E
Eric Dumazet 已提交
4485
	if (skb->csum_bad)
4486 4487
		goto normal;

E
Eric Dumazet 已提交
4488 4489
	gro_list_prepare(napi, skb);

4490 4491
	rcu_read_lock();
	list_for_each_entry_rcu(ptype, head, list) {
4492
		if (ptype->type != type || !ptype->callbacks.gro_receive)
4493 4494
			continue;

4495
		skb_set_network_header(skb, skb_gro_offset(skb));
4496
		skb_reset_mac_len(skb);
4497
		NAPI_GRO_CB(skb)->same_flow = 0;
E
Eric Dumazet 已提交
4498
		NAPI_GRO_CB(skb)->flush = skb_is_gso(skb) || skb_has_frag_list(skb);
H
Herbert Xu 已提交
4499
		NAPI_GRO_CB(skb)->free = 0;
4500
		NAPI_GRO_CB(skb)->encap_mark = 0;
S
Sabrina Dubroca 已提交
4501
		NAPI_GRO_CB(skb)->recursion_counter = 0;
4502
		NAPI_GRO_CB(skb)->is_fou = 0;
4503
		NAPI_GRO_CB(skb)->is_atomic = 1;
4504
		NAPI_GRO_CB(skb)->gro_remcsum_start = 0;
4505

4506 4507 4508 4509 4510 4511 4512 4513 4514 4515 4516 4517 4518 4519 4520
		/* 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;
		}
4521

4522
		pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
4523 4524 4525 4526 4527 4528 4529
		break;
	}
	rcu_read_unlock();

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

H
Herbert Xu 已提交
4530
	same_flow = NAPI_GRO_CB(skb)->same_flow;
4531
	ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
H
Herbert Xu 已提交
4532

4533 4534 4535 4536 4537 4538
	if (pp) {
		struct sk_buff *nskb = *pp;

		*pp = nskb->next;
		nskb->next = NULL;
		napi_gro_complete(nskb);
4539
		napi->gro_count--;
4540 4541
	}

H
Herbert Xu 已提交
4542
	if (same_flow)
4543 4544
		goto ok;

4545
	if (NAPI_GRO_CB(skb)->flush)
4546 4547
		goto normal;

4548 4549 4550 4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561
	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++;
	}
4562
	NAPI_GRO_CB(skb)->count = 1;
4563
	NAPI_GRO_CB(skb)->age = jiffies;
4564
	NAPI_GRO_CB(skb)->last = skb;
4565
	skb_shinfo(skb)->gso_size = skb_gro_len(skb);
4566 4567
	skb->next = napi->gro_list;
	napi->gro_list = skb;
4568
	ret = GRO_HELD;
4569

4570
pull:
4571 4572 4573
	grow = skb_gro_offset(skb) - skb_headlen(skb);
	if (grow > 0)
		gro_pull_from_frag0(skb, grow);
4574
ok:
4575
	return ret;
4576 4577

normal:
4578 4579
	ret = GRO_NORMAL;
	goto pull;
H
Herbert Xu 已提交
4580
}
4581

4582 4583 4584 4585 4586 4587 4588 4589 4590 4591 4592 4593
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;
}
4594
EXPORT_SYMBOL(gro_find_receive_by_type);
4595 4596 4597 4598 4599 4600 4601 4602 4603 4604 4605 4606 4607

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;
}
4608
EXPORT_SYMBOL(gro_find_complete_by_type);
H
Herbert Xu 已提交
4609

R
Rami Rosen 已提交
4610
static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
H
Herbert Xu 已提交
4611
{
4612 4613
	switch (ret) {
	case GRO_NORMAL:
4614
		if (netif_receive_skb_internal(skb))
4615 4616
			ret = GRO_DROP;
		break;
H
Herbert Xu 已提交
4617

4618
	case GRO_DROP:
H
Herbert Xu 已提交
4619 4620
		kfree_skb(skb);
		break;
4621

4622
	case GRO_MERGED_FREE:
4623 4624
		if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD) {
			skb_dst_drop(skb);
4625
			kmem_cache_free(skbuff_head_cache, skb);
4626
		} else {
4627
			__kfree_skb(skb);
4628
		}
4629 4630
		break;

4631 4632 4633
	case GRO_HELD:
	case GRO_MERGED:
		break;
H
Herbert Xu 已提交
4634 4635
	}

4636
	return ret;
4637 4638
}

4639
gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
4640
{
4641
	skb_mark_napi_id(skb, napi);
4642
	trace_napi_gro_receive_entry(skb);
4643

4644 4645
	skb_gro_reset_offset(skb);

E
Eric Dumazet 已提交
4646
	return napi_skb_finish(dev_gro_receive(napi, skb), skb);
4647 4648 4649
}
EXPORT_SYMBOL(napi_gro_receive);

S
stephen hemminger 已提交
4650
static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
4651
{
4652 4653 4654 4655
	if (unlikely(skb->pfmemalloc)) {
		consume_skb(skb);
		return;
	}
4656
	__skb_pull(skb, skb_headlen(skb));
4657 4658
	/* restore the reserve we had after netdev_alloc_skb_ip_align() */
	skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
4659
	skb->vlan_tci = 0;
H
Herbert Xu 已提交
4660
	skb->dev = napi->dev;
A
Andy Gospodarek 已提交
4661
	skb->skb_iif = 0;
4662 4663
	skb->encapsulation = 0;
	skb_shinfo(skb)->gso_type = 0;
4664
	skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
4665 4666 4667 4668

	napi->skb = skb;
}

4669
struct sk_buff *napi_get_frags(struct napi_struct *napi)
H
Herbert Xu 已提交
4670 4671 4672 4673
{
	struct sk_buff *skb = napi->skb;

	if (!skb) {
4674
		skb = napi_alloc_skb(napi, GRO_MAX_HEAD);
4675 4676 4677 4678
		if (skb) {
			napi->skb = skb;
			skb_mark_napi_id(skb, napi);
		}
4679
	}
4680 4681
	return skb;
}
4682
EXPORT_SYMBOL(napi_get_frags);
4683

4684 4685 4686
static gro_result_t napi_frags_finish(struct napi_struct *napi,
				      struct sk_buff *skb,
				      gro_result_t ret)
4687
{
4688 4689
	switch (ret) {
	case GRO_NORMAL:
4690 4691 4692 4693
	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))
4694
			ret = GRO_DROP;
4695
		break;
H
Herbert Xu 已提交
4696

4697 4698 4699 4700
	case GRO_DROP:
	case GRO_MERGED_FREE:
		napi_reuse_skb(napi, skb);
		break;
4701 4702 4703

	case GRO_MERGED:
		break;
4704
	}
H
Herbert Xu 已提交
4705

4706
	return ret;
H
Herbert Xu 已提交
4707
}
4708

4709 4710 4711 4712
/* 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
4713
static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
4714 4715
{
	struct sk_buff *skb = napi->skb;
4716 4717
	const struct ethhdr *eth;
	unsigned int hlen = sizeof(*eth);
4718 4719 4720

	napi->skb = NULL;

4721 4722 4723 4724 4725 4726 4727
	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)) {
4728 4729
			net_warn_ratelimited("%s: dropping impossible skb from %s\n",
					     __func__, napi->dev->name);
4730 4731 4732 4733 4734 4735 4736
			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;
4737
	}
4738 4739 4740 4741 4742 4743 4744 4745
	__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;
4746 4747 4748 4749

	return skb;
}

4750
gro_result_t napi_gro_frags(struct napi_struct *napi)
4751
{
4752
	struct sk_buff *skb = napi_frags_skb(napi);
4753 4754

	if (!skb)
4755
		return GRO_DROP;
4756

4757 4758
	trace_napi_gro_frags_entry(skb);

E
Eric Dumazet 已提交
4759
	return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
4760
}
H
Herbert Xu 已提交
4761 4762
EXPORT_SYMBOL(napi_gro_frags);

T
Tom Herbert 已提交
4763 4764 4765 4766 4767 4768 4769 4770 4771 4772 4773 4774 4775 4776 4777 4778 4779 4780 4781 4782 4783 4784 4785 4786 4787
/* 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);

4788
/*
4789
 * net_rps_action_and_irq_enable sends any pending IPI's for rps.
4790 4791 4792 4793 4794 4795 4796 4797 4798 4799 4800 4801 4802 4803 4804 4805 4806
 * 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))
4807
				smp_call_function_single_async(remsd->cpu,
4808
							   &remsd->csd);
4809 4810 4811 4812 4813 4814 4815
			remsd = next;
		}
	} else
#endif
		local_irq_enable();
}

E
Eric Dumazet 已提交
4816 4817 4818 4819 4820 4821 4822 4823 4824
static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
{
#ifdef CONFIG_RPS
	return sd->rps_ipi_list != NULL;
#else
	return false;
#endif
}

4825
static int process_backlog(struct napi_struct *napi, int quota)
L
Linus Torvalds 已提交
4826
{
E
Eric Dumazet 已提交
4827
	struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
4828 4829
	bool again = true;
	int work = 0;
L
Linus Torvalds 已提交
4830

4831 4832 4833
	/* Check if we have pending ipi, its better to send them now,
	 * not waiting net_rx_action() end.
	 */
E
Eric Dumazet 已提交
4834
	if (sd_has_rps_ipi_waiting(sd)) {
4835 4836 4837
		local_irq_disable();
		net_rps_action_and_irq_enable(sd);
	}
E
Eric Dumazet 已提交
4838

4839
	napi->weight = weight_p;
4840
	while (again) {
L
Linus Torvalds 已提交
4841
		struct sk_buff *skb;
4842 4843

		while ((skb = __skb_dequeue(&sd->process_queue))) {
4844
			rcu_read_lock();
4845
			__netif_receive_skb(skb);
4846
			rcu_read_unlock();
4847
			input_queue_head_incr(sd);
4848
			if (++work >= quota)
4849
				return work;
4850

4851
		}
L
Linus Torvalds 已提交
4852

4853
		local_irq_disable();
E
Eric Dumazet 已提交
4854
		rps_lock(sd);
4855
		if (skb_queue_empty(&sd->input_pkt_queue)) {
E
Eric Dumazet 已提交
4856 4857 4858
			/*
			 * Inline a custom version of __napi_complete().
			 * only current cpu owns and manipulates this napi,
4859 4860 4861
			 * 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
4862 4863 4864
			 * and we dont need an smp_mb() memory barrier.
			 */
			napi->state = 0;
4865 4866 4867 4868
			again = false;
		} else {
			skb_queue_splice_tail_init(&sd->input_pkt_queue,
						   &sd->process_queue);
4869
		}
E
Eric Dumazet 已提交
4870
		rps_unlock(sd);
4871
		local_irq_enable();
4872
	}
L
Linus Torvalds 已提交
4873

4874 4875
	return work;
}
L
Linus Torvalds 已提交
4876

4877 4878
/**
 * __napi_schedule - schedule for receive
4879
 * @n: entry to schedule
4880
 *
4881 4882
 * The entry's receive function will be scheduled to run.
 * Consider using __napi_schedule_irqoff() if hard irqs are masked.
4883
 */
H
Harvey Harrison 已提交
4884
void __napi_schedule(struct napi_struct *n)
4885 4886
{
	unsigned long flags;
L
Linus Torvalds 已提交
4887

4888
	local_irq_save(flags);
4889
	____napi_schedule(this_cpu_ptr(&softnet_data), n);
4890
	local_irq_restore(flags);
L
Linus Torvalds 已提交
4891
}
4892 4893
EXPORT_SYMBOL(__napi_schedule);

4894 4895 4896 4897 4898 4899 4900 4901 4902 4903 4904 4905
/**
 * __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);

4906 4907 4908 4909
void __napi_complete(struct napi_struct *n)
{
	BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));

E
Eric Dumazet 已提交
4910
	list_del_init(&n->poll_list);
4911
	smp_mb__before_atomic();
4912 4913 4914 4915
	clear_bit(NAPI_STATE_SCHED, &n->state);
}
EXPORT_SYMBOL(__napi_complete);

4916
void napi_complete_done(struct napi_struct *n, int work_done)
4917 4918 4919 4920 4921 4922 4923 4924 4925 4926
{
	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;

4927 4928
	if (n->gro_list) {
		unsigned long timeout = 0;
E
Eric Dumazet 已提交
4929

4930 4931 4932 4933 4934 4935 4936 4937 4938
		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
4939 4940 4941 4942 4943 4944 4945 4946
	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);
	}
4947
}
4948
EXPORT_SYMBOL(napi_complete_done);
4949

E
Eliezer Tamir 已提交
4950
/* must be called under rcu_read_lock(), as we dont take a reference */
E
Eric Dumazet 已提交
4951
static struct napi_struct *napi_by_id(unsigned int napi_id)
E
Eliezer Tamir 已提交
4952 4953 4954 4955 4956 4957 4958 4959 4960 4961
{
	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
4962 4963

#if defined(CONFIG_NET_RX_BUSY_POLL)
4964
#define BUSY_POLL_BUDGET 8
E
Eric Dumazet 已提交
4965 4966 4967
bool sk_busy_loop(struct sock *sk, int nonblock)
{
	unsigned long end_time = !nonblock ? sk_busy_loop_end_time(sk) : 0;
4968
	int (*busy_poll)(struct napi_struct *dev);
E
Eric Dumazet 已提交
4969 4970 4971
	struct napi_struct *napi;
	int rc = false;

4972
	rcu_read_lock();
E
Eric Dumazet 已提交
4973 4974 4975 4976 4977

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

4978 4979
	/* 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
4980 4981

	do {
4982
		rc = 0;
4983
		local_bh_disable();
4984 4985 4986 4987 4988 4989 4990
		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);
4991
				trace_napi_poll(napi, rc, BUSY_POLL_BUDGET);
4992 4993 4994 4995 4996 4997 4998
				if (rc == BUSY_POLL_BUDGET) {
					napi_complete_done(napi, rc);
					napi_schedule(napi);
				}
			}
			netpoll_poll_unlock(have);
		}
4999
		if (rc > 0)
5000 5001
			__NET_ADD_STATS(sock_net(sk),
					LINUX_MIB_BUSYPOLLRXPACKETS, rc);
5002
		local_bh_enable();
E
Eric Dumazet 已提交
5003 5004 5005 5006 5007 5008 5009 5010 5011 5012

		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:
5013
	rcu_read_unlock();
E
Eric Dumazet 已提交
5014 5015 5016 5017 5018
	return rc;
}
EXPORT_SYMBOL(sk_busy_loop);

#endif /* CONFIG_NET_RX_BUSY_POLL */
E
Eliezer Tamir 已提交
5019 5020 5021

void napi_hash_add(struct napi_struct *napi)
{
E
Eric Dumazet 已提交
5022 5023
	if (test_bit(NAPI_STATE_NO_BUSY_POLL, &napi->state) ||
	    test_and_set_bit(NAPI_STATE_HASHED, &napi->state))
5024
		return;
E
Eliezer Tamir 已提交
5025

5026
	spin_lock(&napi_hash_lock);
E
Eliezer Tamir 已提交
5027

5028 5029 5030 5031 5032 5033
	/* 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
5034

5035 5036
	hlist_add_head_rcu(&napi->napi_hash_node,
			   &napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
E
Eliezer Tamir 已提交
5037

5038
	spin_unlock(&napi_hash_lock);
E
Eliezer Tamir 已提交
5039 5040 5041 5042 5043 5044
}
EXPORT_SYMBOL_GPL(napi_hash_add);

/* Warning : caller is responsible to make sure rcu grace period
 * is respected before freeing memory containing @napi
 */
5045
bool napi_hash_del(struct napi_struct *napi)
E
Eliezer Tamir 已提交
5046
{
5047 5048
	bool rcu_sync_needed = false;

E
Eliezer Tamir 已提交
5049 5050
	spin_lock(&napi_hash_lock);

5051 5052
	if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state)) {
		rcu_sync_needed = true;
E
Eliezer Tamir 已提交
5053
		hlist_del_rcu(&napi->napi_hash_node);
5054
	}
E
Eliezer Tamir 已提交
5055
	spin_unlock(&napi_hash_lock);
5056
	return rcu_sync_needed;
E
Eliezer Tamir 已提交
5057 5058 5059
}
EXPORT_SYMBOL_GPL(napi_hash_del);

5060 5061 5062 5063 5064 5065 5066 5067 5068 5069 5070
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;
}

5071 5072 5073 5074
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);
5075 5076
	hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED);
	napi->timer.function = napi_watchdog;
5077
	napi->gro_count = 0;
5078
	napi->gro_list = NULL;
H
Herbert Xu 已提交
5079
	napi->skb = NULL;
5080
	napi->poll = poll;
E
Eric Dumazet 已提交
5081 5082 5083
	if (weight > NAPI_POLL_WEIGHT)
		pr_err_once("netif_napi_add() called with weight %d on device %s\n",
			    weight, dev->name);
5084 5085 5086
	napi->weight = weight;
	list_add(&napi->dev_list, &dev->napi_list);
	napi->dev = dev;
H
Herbert Xu 已提交
5087
#ifdef CONFIG_NETPOLL
5088 5089 5090 5091
	spin_lock_init(&napi->poll_lock);
	napi->poll_owner = -1;
#endif
	set_bit(NAPI_STATE_SCHED, &napi->state);
5092
	napi_hash_add(napi);
5093 5094 5095
}
EXPORT_SYMBOL(netif_napi_add);

5096 5097 5098 5099 5100 5101 5102
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);
5103 5104
	while (test_and_set_bit(NAPI_STATE_NPSVC, &n->state))
		msleep(1);
5105 5106 5107 5108 5109 5110 5111

	hrtimer_cancel(&n->timer);

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

5112
/* Must be called in process context */
5113 5114
void netif_napi_del(struct napi_struct *napi)
{
5115 5116 5117
	might_sleep();
	if (napi_hash_del(napi))
		synchronize_net();
5118
	list_del_init(&napi->dev_list);
5119
	napi_free_frags(napi);
5120

E
Eric Dumazet 已提交
5121
	kfree_skb_list(napi->gro_list);
5122
	napi->gro_list = NULL;
5123
	napi->gro_count = 0;
5124 5125 5126
}
EXPORT_SYMBOL(netif_napi_del);

5127 5128 5129 5130 5131 5132 5133 5134 5135 5136 5137 5138 5139 5140 5141 5142 5143 5144 5145 5146
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);
5147
		trace_napi_poll(n, work, weight);
5148 5149 5150 5151 5152 5153 5154 5155 5156 5157 5158 5159 5160 5161 5162 5163 5164 5165 5166 5167 5168 5169 5170 5171
	}

	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);
	}

5172 5173 5174 5175 5176 5177 5178 5179 5180
	/* 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;
	}

5181 5182 5183 5184 5185 5186 5187 5188
	list_add_tail(&n->poll_list, repoll);

out_unlock:
	netpoll_poll_unlock(have);

	return work;
}

5189
static __latent_entropy void net_rx_action(struct softirq_action *h)
L
Linus Torvalds 已提交
5190
{
5191
	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
5192
	unsigned long time_limit = jiffies + 2;
5193
	int budget = netdev_budget;
E
Eric Dumazet 已提交
5194 5195
	LIST_HEAD(list);
	LIST_HEAD(repoll);
5196

L
Linus Torvalds 已提交
5197
	local_irq_disable();
E
Eric Dumazet 已提交
5198 5199
	list_splice_init(&sd->poll_list, &list);
	local_irq_enable();
L
Linus Torvalds 已提交
5200

H
Herbert Xu 已提交
5201
	for (;;) {
5202
		struct napi_struct *n;
L
Linus Torvalds 已提交
5203

H
Herbert Xu 已提交
5204 5205 5206 5207 5208 5209
		if (list_empty(&list)) {
			if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll))
				return;
			break;
		}

5210 5211 5212
		n = list_first_entry(&list, struct napi_struct, poll_list);
		budget -= napi_poll(n, &repoll);

E
Eric Dumazet 已提交
5213
		/* If softirq window is exhausted then punt.
5214 5215
		 * Allow this to run for 2 jiffies since which will allow
		 * an average latency of 1.5/HZ.
5216
		 */
H
Herbert Xu 已提交
5217 5218 5219 5220 5221
		if (unlikely(budget <= 0 ||
			     time_after_eq(jiffies, time_limit))) {
			sd->time_squeeze++;
			break;
		}
L
Linus Torvalds 已提交
5222
	}
E
Eric Dumazet 已提交
5223

5224
	__kfree_skb_flush();
E
Eric Dumazet 已提交
5225 5226 5227 5228 5229 5230 5231 5232
	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);

5233
	net_rps_action_and_irq_enable(sd);
L
Linus Torvalds 已提交
5234 5235
}

5236
struct netdev_adjacent {
J
Jiri Pirko 已提交
5237
	struct net_device *dev;
5238 5239

	/* upper master flag, there can only be one master device per list */
J
Jiri Pirko 已提交
5240
	bool master;
5241 5242 5243 5244

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

5245 5246 5247
	/* private field for the users */
	void *private;

J
Jiri Pirko 已提交
5248 5249 5250 5251
	struct list_head list;
	struct rcu_head rcu;
};

5252
static struct netdev_adjacent *__netdev_find_adj(struct net_device *adj_dev,
5253
						 struct list_head *adj_list)
J
Jiri Pirko 已提交
5254
{
5255 5256
	struct netdev_adjacent *adj;

5257
	list_for_each_entry(adj, adj_list, list) {
5258 5259
		if (adj->dev == adj_dev)
			return adj;
J
Jiri Pirko 已提交
5260 5261 5262 5263
	}
	return NULL;
}

5264 5265 5266 5267 5268 5269 5270
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
5271 5272 5273 5274 5275 5276 5277 5278 5279 5280 5281 5282 5283 5284
/**
 * 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();

5285 5286
	return netdev_walk_all_upper_dev_rcu(dev, __netdev_has_upper_dev,
					     upper_dev);
J
Jiri Pirko 已提交
5287 5288 5289
}
EXPORT_SYMBOL(netdev_has_upper_dev);

5290 5291 5292 5293 5294 5295 5296 5297 5298 5299 5300 5301 5302 5303 5304 5305 5306 5307
/**
 * 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
5308 5309 5310 5311 5312 5313 5314
/**
 * 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
5315
static bool netdev_has_any_upper_dev(struct net_device *dev)
J
Jiri Pirko 已提交
5316 5317 5318
{
	ASSERT_RTNL();

5319
	return !list_empty(&dev->adj_list.upper);
J
Jiri Pirko 已提交
5320 5321 5322 5323 5324 5325 5326 5327 5328 5329 5330
}

/**
 * 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)
{
5331
	struct netdev_adjacent *upper;
J
Jiri Pirko 已提交
5332 5333 5334

	ASSERT_RTNL();

5335
	if (list_empty(&dev->adj_list.upper))
J
Jiri Pirko 已提交
5336 5337
		return NULL;

5338
	upper = list_first_entry(&dev->adj_list.upper,
5339
				 struct netdev_adjacent, list);
J
Jiri Pirko 已提交
5340 5341 5342 5343 5344 5345
	if (likely(upper->master))
		return upper->dev;
	return NULL;
}
EXPORT_SYMBOL(netdev_master_upper_dev_get);

5346 5347 5348 5349 5350 5351 5352 5353 5354 5355 5356 5357 5358 5359
/**
 * 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);
}

5360 5361 5362 5363 5364 5365 5366 5367 5368 5369
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);

5370 5371 5372 5373 5374 5375 5376 5377 5378 5379 5380 5381 5382 5383 5384 5385 5386 5387 5388 5389 5390 5391 5392 5393 5394 5395
/**
 * 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);

5396 5397 5398 5399 5400 5401 5402 5403 5404 5405 5406 5407 5408 5409 5410 5411 5412 5413 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
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);

5441 5442 5443 5444 5445 5446 5447 5448 5449
/**
 * 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
5450
 * list will remain unchanged.
5451 5452 5453 5454 5455 5456 5457 5458 5459 5460 5461
 */
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;

5462
	*iter = lower->list.next;
5463 5464 5465 5466 5467 5468 5469 5470 5471 5472 5473 5474 5475 5476 5477 5478 5479 5480 5481 5482 5483 5484 5485 5486 5487 5488 5489

	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;

5490
	*iter = &lower->list;
5491 5492 5493 5494 5495

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

5496 5497 5498 5499 5500 5501 5502 5503 5504
/**
 * 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
5505
 * list will remain unchanged.
5506 5507 5508 5509 5510
 */
void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
{
	struct netdev_adjacent *lower;

5511
	lower = list_entry(*iter, struct netdev_adjacent, list);
5512 5513 5514 5515

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

5516
	*iter = lower->list.next;
5517 5518 5519 5520 5521

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

5522 5523 5524 5525 5526
static struct net_device *netdev_next_lower_dev(struct net_device *dev,
						struct list_head **iter)
{
	struct netdev_adjacent *lower;

5527
	lower = list_entry((*iter)->next, struct netdev_adjacent, list);
5528 5529 5530 5531

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

5532
	*iter = &lower->list;
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 5558 5559 5560 5561 5562 5563 5564 5565 5566 5567 5568 5569 5570 5571 5572 5573 5574 5575 5576 5577 5578 5579 5580 5581 5582 5583 5584 5585 5586 5587 5588 5589 5590 5591 5592 5593 5594 5595 5596 5597 5598 5599 5600 5601 5602 5603 5604 5605 5606

	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);

5607 5608 5609 5610 5611 5612 5613 5614 5615 5616 5617 5618 5619 5620 5621 5622 5623 5624 5625 5626 5627
/**
 * 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
5628 5629 5630 5631 5632 5633 5634 5635 5636
/**
 * 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)
{
5637
	struct netdev_adjacent *upper;
J
Jiri Pirko 已提交
5638

5639
	upper = list_first_or_null_rcu(&dev->adj_list.upper,
5640
				       struct netdev_adjacent, list);
J
Jiri Pirko 已提交
5641 5642 5643 5644 5645 5646
	if (upper && likely(upper->master))
		return upper->dev;
	return NULL;
}
EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);

5647
static int netdev_adjacent_sysfs_add(struct net_device *dev,
5648 5649 5650 5651 5652 5653 5654 5655 5656
			      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);
}
5657
static void netdev_adjacent_sysfs_del(struct net_device *dev,
5658 5659 5660 5661 5662 5663 5664 5665 5666
			       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);
}

5667 5668 5669 5670 5671 5672 5673 5674
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));
}
5675

5676 5677
static int __netdev_adjacent_dev_insert(struct net_device *dev,
					struct net_device *adj_dev,
5678
					struct list_head *dev_list,
5679
					void *private, bool master)
5680 5681
{
	struct netdev_adjacent *adj;
5682
	int ret;
5683

5684
	adj = __netdev_find_adj(adj_dev, dev_list);
5685 5686

	if (adj) {
5687
		adj->ref_nr += 1;
5688 5689 5690
		pr_debug("Insert adjacency: dev %s adj_dev %s adj->ref_nr %d\n",
			 dev->name, adj_dev->name, adj->ref_nr);

5691 5692 5693 5694 5695 5696 5697 5698 5699
		return 0;
	}

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

	adj->dev = adj_dev;
	adj->master = master;
5700
	adj->ref_nr = 1;
5701
	adj->private = private;
5702
	dev_hold(adj_dev);
5703

5704 5705
	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);
5706

5707
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
5708
		ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
5709 5710 5711 5712
		if (ret)
			goto free_adj;
	}

5713
	/* Ensure that master link is always the first item in list. */
5714 5715 5716 5717
	if (master) {
		ret = sysfs_create_link(&(dev->dev.kobj),
					&(adj_dev->dev.kobj), "master");
		if (ret)
5718
			goto remove_symlinks;
5719

5720
		list_add_rcu(&adj->list, dev_list);
5721
	} else {
5722
		list_add_tail_rcu(&adj->list, dev_list);
5723
	}
5724 5725

	return 0;
5726

5727
remove_symlinks:
5728
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
5729
		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
5730 5731
free_adj:
	kfree(adj);
5732
	dev_put(adj_dev);
5733 5734

	return ret;
5735 5736
}

S
stephen hemminger 已提交
5737 5738
static void __netdev_adjacent_dev_remove(struct net_device *dev,
					 struct net_device *adj_dev,
5739
					 u16 ref_nr,
S
stephen hemminger 已提交
5740
					 struct list_head *dev_list)
5741 5742 5743
{
	struct netdev_adjacent *adj;

5744 5745 5746
	pr_debug("Remove adjacency: dev %s adj_dev %s ref_nr %d\n",
		 dev->name, adj_dev->name, ref_nr);

5747
	adj = __netdev_find_adj(adj_dev, dev_list);
5748

5749
	if (!adj) {
5750
		pr_err("Adjacency does not exist for device %s from %s\n",
5751
		       dev->name, adj_dev->name);
5752 5753
		WARN_ON(1);
		return;
5754
	}
5755

5756
	if (adj->ref_nr > ref_nr) {
5757 5758 5759
		pr_debug("adjacency: %s to %s ref_nr - %d = %d\n",
			 dev->name, adj_dev->name, ref_nr,
			 adj->ref_nr - ref_nr);
5760
		adj->ref_nr -= ref_nr;
5761 5762 5763
		return;
	}

5764 5765 5766
	if (adj->master)
		sysfs_remove_link(&(dev->dev.kobj), "master");

5767
	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
5768
		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
5769

5770
	list_del_rcu(&adj->list);
5771
	pr_debug("adjacency: dev_put for %s, because link removed from %s to %s\n",
5772
		 adj_dev->name, dev->name, adj_dev->name);
5773 5774 5775 5776
	dev_put(adj_dev);
	kfree_rcu(adj, rcu);
}

S
stephen hemminger 已提交
5777 5778 5779 5780 5781
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)
5782 5783 5784
{
	int ret;

5785
	ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list,
5786
					   private, master);
5787 5788 5789
	if (ret)
		return ret;

5790
	ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list,
5791
					   private, false);
5792
	if (ret) {
5793
		__netdev_adjacent_dev_remove(dev, upper_dev, 1, up_list);
5794 5795 5796 5797 5798 5799
		return ret;
	}

	return 0;
}

S
stephen hemminger 已提交
5800 5801
static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
					       struct net_device *upper_dev,
5802
					       u16 ref_nr,
S
stephen hemminger 已提交
5803 5804
					       struct list_head *up_list,
					       struct list_head *down_list)
5805
{
5806 5807
	__netdev_adjacent_dev_remove(dev, upper_dev, ref_nr, up_list);
	__netdev_adjacent_dev_remove(upper_dev, dev, ref_nr, down_list);
5808 5809
}

S
stephen hemminger 已提交
5810 5811 5812
static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
						struct net_device *upper_dev,
						void *private, bool master)
5813
{
5814 5815 5816 5817
	return __netdev_adjacent_dev_link_lists(dev, upper_dev,
						&dev->adj_list.upper,
						&upper_dev->adj_list.lower,
						private, master);
5818 5819
}

S
stephen hemminger 已提交
5820 5821
static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
						   struct net_device *upper_dev)
5822
{
5823
	__netdev_adjacent_dev_unlink_lists(dev, upper_dev, 1,
5824 5825 5826
					   &dev->adj_list.upper,
					   &upper_dev->adj_list.lower);
}
5827

J
Jiri Pirko 已提交
5828
static int __netdev_upper_dev_link(struct net_device *dev,
5829
				   struct net_device *upper_dev, bool master,
5830
				   void *upper_priv, void *upper_info)
J
Jiri Pirko 已提交
5831
{
5832
	struct netdev_notifier_changeupper_info changeupper_info;
5833
	int ret = 0;
J
Jiri Pirko 已提交
5834 5835 5836 5837 5838 5839 5840

	ASSERT_RTNL();

	if (dev == upper_dev)
		return -EBUSY;

	/* To prevent loops, check if dev is not upper device to upper_dev. */
5841
	if (netdev_has_upper_dev(upper_dev, dev))
J
Jiri Pirko 已提交
5842 5843
		return -EBUSY;

5844
	if (netdev_has_upper_dev(dev, upper_dev))
J
Jiri Pirko 已提交
5845 5846 5847 5848 5849
		return -EEXIST;

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

5850 5851 5852
	changeupper_info.upper_dev = upper_dev;
	changeupper_info.master = master;
	changeupper_info.linking = true;
5853
	changeupper_info.upper_info = upper_info;
5854

5855 5856 5857 5858 5859 5860
	ret = call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, dev,
					    &changeupper_info.info);
	ret = notifier_to_errno(ret);
	if (ret)
		return ret;

5861
	ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, upper_priv,
5862
						   master);
5863 5864
	if (ret)
		return ret;
J
Jiri Pirko 已提交
5865

5866 5867 5868 5869
	ret = call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev,
					    &changeupper_info.info);
	ret = notifier_to_errno(ret);
	if (ret)
5870
		goto rollback;
5871

J
Jiri Pirko 已提交
5872
	return 0;
5873

5874
rollback:
5875
	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5876 5877

	return ret;
J
Jiri Pirko 已提交
5878 5879 5880 5881 5882 5883 5884 5885 5886 5887 5888 5889 5890 5891 5892
}

/**
 * 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)
{
5893
	return __netdev_upper_dev_link(dev, upper_dev, false, NULL, NULL);
J
Jiri Pirko 已提交
5894 5895 5896 5897 5898 5899 5900
}
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
5901
 * @upper_priv: upper device private
5902
 * @upper_info: upper info to be passed down via notifier
J
Jiri Pirko 已提交
5903 5904 5905 5906 5907 5908 5909 5910
 *
 * 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,
5911
				 struct net_device *upper_dev,
5912
				 void *upper_priv, void *upper_info)
J
Jiri Pirko 已提交
5913
{
5914 5915
	return __netdev_upper_dev_link(dev, upper_dev, true,
				       upper_priv, upper_info);
J
Jiri Pirko 已提交
5916 5917 5918 5919 5920 5921 5922 5923 5924 5925 5926 5927 5928 5929
}
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)
{
5930
	struct netdev_notifier_changeupper_info changeupper_info;
J
Jiri Pirko 已提交
5931 5932
	ASSERT_RTNL();

5933 5934 5935 5936
	changeupper_info.upper_dev = upper_dev;
	changeupper_info.master = netdev_master_upper_dev_get(dev) == upper_dev;
	changeupper_info.linking = false;

5937 5938 5939
	call_netdevice_notifiers_info(NETDEV_PRECHANGEUPPER, dev,
				      &changeupper_info.info);

5940
	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
5941

5942 5943
	call_netdevice_notifiers_info(NETDEV_CHANGEUPPER, dev,
				      &changeupper_info.info);
J
Jiri Pirko 已提交
5944 5945 5946
}
EXPORT_SYMBOL(netdev_upper_dev_unlink);

5947 5948 5949
/**
 * netdev_bonding_info_change - Dispatch event about slave change
 * @dev: device
5950
 * @bonding_info: info to dispatch
5951 5952 5953 5954 5955 5956 5957 5958 5959 5960 5961 5962 5963 5964 5965 5966
 *
 * 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
5967
static void netdev_adjacent_add_links(struct net_device *dev)
5968 5969 5970 5971 5972 5973
{
	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
5974
		if (!net_eq(net, dev_net(iter->dev)))
5975 5976 5977 5978 5979 5980 5981 5982
			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
5983
		if (!net_eq(net, dev_net(iter->dev)))
5984 5985 5986 5987 5988 5989 5990 5991
			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
5992
static void netdev_adjacent_del_links(struct net_device *dev)
5993 5994 5995 5996 5997 5998
{
	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
5999
		if (!net_eq(net, dev_net(iter->dev)))
6000 6001 6002 6003 6004 6005 6006 6007
			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
6008
		if (!net_eq(net, dev_net(iter->dev)))
6009 6010 6011 6012 6013 6014 6015 6016
			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);
	}
}

6017
void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
6018
{
6019
	struct netdev_adjacent *iter;
6020

6021 6022
	struct net *net = dev_net(dev);

6023
	list_for_each_entry(iter, &dev->adj_list.upper, list) {
W
Wei Tang 已提交
6024
		if (!net_eq(net, dev_net(iter->dev)))
6025
			continue;
6026 6027 6028 6029 6030
		netdev_adjacent_sysfs_del(iter->dev, oldname,
					  &iter->dev->adj_list.lower);
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.lower);
	}
6031

6032
	list_for_each_entry(iter, &dev->adj_list.lower, list) {
W
Wei Tang 已提交
6033
		if (!net_eq(net, dev_net(iter->dev)))
6034
			continue;
6035 6036 6037 6038 6039
		netdev_adjacent_sysfs_del(iter->dev, oldname,
					  &iter->dev->adj_list.upper);
		netdev_adjacent_sysfs_add(iter->dev, dev,
					  &iter->dev->adj_list.upper);
	}
6040 6041 6042 6043 6044 6045 6046 6047 6048
}

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

	if (!lower_dev)
		return NULL;
6049
	lower = __netdev_find_adj(lower_dev, &dev->adj_list.lower);
6050 6051 6052 6053 6054 6055 6056
	if (!lower)
		return NULL;

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

6057

6058
int dev_get_nest_level(struct net_device *dev)
6059 6060 6061 6062 6063 6064 6065 6066 6067
{
	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) {
6068
		nest = dev_get_nest_level(lower);
6069 6070 6071 6072
		if (max_nest < nest)
			max_nest = nest;
	}

6073
	return max_nest + 1;
6074 6075 6076
}
EXPORT_SYMBOL(dev_get_nest_level);

6077 6078 6079 6080 6081 6082 6083 6084 6085 6086 6087 6088 6089 6090 6091 6092 6093 6094 6095 6096
/**
 * 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);

6097 6098 6099 6100 6101 6102 6103 6104 6105 6106 6107 6108 6109 6110 6111 6112 6113 6114 6115 6116 6117 6118 6119 6120 6121 6122 6123 6124 6125 6126 6127 6128 6129 6130 6131 6132 6133 6134 6135 6136 6137 6138 6139 6140
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);

6141 6142
static void dev_change_rx_flags(struct net_device *dev, int flags)
{
6143 6144
	const struct net_device_ops *ops = dev->netdev_ops;

6145
	if (ops->ndo_change_rx_flags)
6146
		ops->ndo_change_rx_flags(dev, flags);
6147 6148
}

6149
static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
L
Linus Torvalds 已提交
6150
{
6151
	unsigned int old_flags = dev->flags;
6152 6153
	kuid_t uid;
	kgid_t gid;
L
Linus Torvalds 已提交
6154

6155 6156
	ASSERT_RTNL();

6157 6158 6159 6160 6161 6162 6163 6164 6165 6166 6167
	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;
6168 6169
			pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
				dev->name);
6170 6171 6172
			return -EOVERFLOW;
		}
	}
6173
	if (dev->flags != old_flags) {
6174 6175 6176
		pr_info("device %s %s promiscuous mode\n",
			dev->name,
			dev->flags & IFF_PROMISC ? "entered" : "left");
6177 6178
		if (audit_enabled) {
			current_uid_gid(&uid, &gid);
6179 6180 6181 6182 6183
			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),
6184
				from_kuid(&init_user_ns, audit_get_loginuid(current)),
6185 6186
				from_kuid(&init_user_ns, uid),
				from_kgid(&init_user_ns, gid),
6187
				audit_get_sessionid(current));
6188
		}
6189

6190
		dev_change_rx_flags(dev, IFF_PROMISC);
L
Linus Torvalds 已提交
6191
	}
6192 6193
	if (notify)
		__dev_notify_flags(dev, old_flags, IFF_PROMISC);
6194
	return 0;
L
Linus Torvalds 已提交
6195 6196
}

6197 6198 6199 6200 6201 6202 6203 6204 6205
/**
 *	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.
6206
 *	Return 0 if successful or a negative errno code on error.
6207
 */
6208
int dev_set_promiscuity(struct net_device *dev, int inc)
6209
{
6210
	unsigned int old_flags = dev->flags;
6211
	int err;
6212

6213
	err = __dev_set_promiscuity(dev, inc, true);
6214
	if (err < 0)
6215
		return err;
6216 6217
	if (dev->flags != old_flags)
		dev_set_rx_mode(dev);
6218
	return err;
6219
}
E
Eric Dumazet 已提交
6220
EXPORT_SYMBOL(dev_set_promiscuity);
6221

6222
static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
L
Linus Torvalds 已提交
6223
{
6224
	unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
L
Linus Torvalds 已提交
6225

6226 6227
	ASSERT_RTNL();

L
Linus Torvalds 已提交
6228
	dev->flags |= IFF_ALLMULTI;
6229 6230 6231 6232 6233 6234 6235 6236 6237 6238
	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;
6239 6240
			pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
				dev->name);
6241 6242 6243
			return -EOVERFLOW;
		}
	}
6244
	if (dev->flags ^ old_flags) {
6245
		dev_change_rx_flags(dev, IFF_ALLMULTI);
6246
		dev_set_rx_mode(dev);
6247 6248 6249
		if (notify)
			__dev_notify_flags(dev, old_flags,
					   dev->gflags ^ old_gflags);
6250
	}
6251
	return 0;
6252
}
6253 6254 6255 6256 6257 6258 6259 6260 6261 6262 6263 6264 6265 6266 6267 6268 6269 6270

/**
 *	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
6271
EXPORT_SYMBOL(dev_set_allmulti);
6272 6273 6274 6275

/*
 *	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
6276
 *	filtering it is put in promiscuous mode while unicast addresses
6277 6278 6279 6280
 *	are present.
 */
void __dev_set_rx_mode(struct net_device *dev)
{
6281 6282
	const struct net_device_ops *ops = dev->netdev_ops;

6283 6284 6285 6286 6287
	/* dev_open will call this function so the list will stay sane. */
	if (!(dev->flags&IFF_UP))
		return;

	if (!netif_device_present(dev))
6288
		return;
6289

6290
	if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
6291 6292 6293
		/* Unicast addresses changes may only happen under the rtnl,
		 * therefore calling __dev_set_promiscuity here is safe.
		 */
6294
		if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
6295
			__dev_set_promiscuity(dev, 1, false);
6296
			dev->uc_promisc = true;
6297
		} else if (netdev_uc_empty(dev) && dev->uc_promisc) {
6298
			__dev_set_promiscuity(dev, -1, false);
6299
			dev->uc_promisc = false;
6300 6301
		}
	}
6302 6303 6304

	if (ops->ndo_set_rx_mode)
		ops->ndo_set_rx_mode(dev);
6305 6306 6307 6308
}

void dev_set_rx_mode(struct net_device *dev)
{
6309
	netif_addr_lock_bh(dev);
6310
	__dev_set_rx_mode(dev);
6311
	netif_addr_unlock_bh(dev);
L
Linus Torvalds 已提交
6312 6313
}

6314 6315 6316 6317 6318 6319
/**
 *	dev_get_flags - get flags reported to userspace
 *	@dev: device
 *
 *	Get the combination of flag bits exported through APIs to userspace.
 */
6320
unsigned int dev_get_flags(const struct net_device *dev)
L
Linus Torvalds 已提交
6321
{
6322
	unsigned int flags;
L
Linus Torvalds 已提交
6323 6324 6325

	flags = (dev->flags & ~(IFF_PROMISC |
				IFF_ALLMULTI |
S
Stefan Rompf 已提交
6326 6327 6328
				IFF_RUNNING |
				IFF_LOWER_UP |
				IFF_DORMANT)) |
L
Linus Torvalds 已提交
6329 6330 6331
		(dev->gflags & (IFF_PROMISC |
				IFF_ALLMULTI));

S
Stefan Rompf 已提交
6332 6333 6334 6335 6336 6337 6338 6339
	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
6340 6341 6342

	return flags;
}
E
Eric Dumazet 已提交
6343
EXPORT_SYMBOL(dev_get_flags);
L
Linus Torvalds 已提交
6344

6345
int __dev_change_flags(struct net_device *dev, unsigned int flags)
L
Linus Torvalds 已提交
6346
{
6347
	unsigned int old_flags = dev->flags;
6348
	int ret;
L
Linus Torvalds 已提交
6349

6350 6351
	ASSERT_RTNL();

L
Linus Torvalds 已提交
6352 6353 6354 6355 6356 6357 6358 6359 6360 6361 6362 6363 6364 6365
	/*
	 *	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.
	 */

6366 6367
	if ((old_flags ^ flags) & IFF_MULTICAST)
		dev_change_rx_flags(dev, IFF_MULTICAST);
6368

6369
	dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
6370 6371 6372 6373 6374 6375 6376 6377

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

	ret = 0;
6378
	if ((old_flags ^ flags) & IFF_UP)
6379
		ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
L
Linus Torvalds 已提交
6380 6381

	if ((flags ^ dev->gflags) & IFF_PROMISC) {
E
Eric Dumazet 已提交
6382
		int inc = (flags & IFF_PROMISC) ? 1 : -1;
6383
		unsigned int old_flags = dev->flags;
E
Eric Dumazet 已提交
6384

L
Linus Torvalds 已提交
6385
		dev->gflags ^= IFF_PROMISC;
6386 6387 6388 6389

		if (__dev_set_promiscuity(dev, inc, false) >= 0)
			if (dev->flags != old_flags)
				dev_set_rx_mode(dev);
L
Linus Torvalds 已提交
6390 6391 6392 6393 6394 6395 6396
	}

	/* 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
6397 6398
		int inc = (flags & IFF_ALLMULTI) ? 1 : -1;

L
Linus Torvalds 已提交
6399
		dev->gflags ^= IFF_ALLMULTI;
6400
		__dev_set_allmulti(dev, inc, false);
L
Linus Torvalds 已提交
6401 6402
	}

6403 6404 6405
	return ret;
}

6406 6407
void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
			unsigned int gchanges)
6408 6409 6410
{
	unsigned int changes = dev->flags ^ old_flags;

6411
	if (gchanges)
6412
		rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
6413

6414 6415 6416 6417 6418 6419 6420 6421
	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 &&
6422 6423 6424 6425 6426 6427 6428
	    (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);
	}
6429 6430 6431 6432 6433 6434 6435 6436 6437 6438
}

/**
 *	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.
 */
6439
int dev_change_flags(struct net_device *dev, unsigned int flags)
6440
{
6441
	int ret;
6442
	unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
6443 6444 6445 6446 6447

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

6448
	changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
6449
	__dev_notify_flags(dev, old_flags, changes);
L
Linus Torvalds 已提交
6450 6451
	return ret;
}
E
Eric Dumazet 已提交
6452
EXPORT_SYMBOL(dev_change_flags);
L
Linus Torvalds 已提交
6453

6454 6455 6456 6457 6458 6459 6460 6461 6462 6463 6464
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;
}

6465 6466 6467 6468 6469 6470 6471
/**
 *	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
6472 6473
int dev_set_mtu(struct net_device *dev, int new_mtu)
{
6474
	int err, orig_mtu;
L
Linus Torvalds 已提交
6475 6476 6477 6478

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

6479 6480 6481 6482
	/* 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
6483
		return -EINVAL;
6484 6485 6486 6487
	}

	if (dev->max_mtu > 0 && new_mtu > dev->max_mtu) {
		net_err_ratelimited("%s: Invalid MTU %d requested, hw max %d\n",
6488
				    dev->name, new_mtu, dev->max_mtu);
6489 6490
		return -EINVAL;
	}
L
Linus Torvalds 已提交
6491 6492 6493 6494

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

6495 6496 6497 6498
	err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
	err = notifier_to_errno(err);
	if (err)
		return err;
6499

6500 6501
	orig_mtu = dev->mtu;
	err = __dev_set_mtu(dev, new_mtu);
6502

6503 6504 6505 6506 6507 6508 6509 6510 6511 6512 6513
	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
6514 6515
	return err;
}
E
Eric Dumazet 已提交
6516
EXPORT_SYMBOL(dev_set_mtu);
L
Linus Torvalds 已提交
6517

6518 6519 6520 6521 6522 6523 6524 6525 6526 6527 6528
/**
 *	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);

6529 6530 6531 6532 6533 6534 6535
/**
 *	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
6536 6537
int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
{
6538
	const struct net_device_ops *ops = dev->netdev_ops;
L
Linus Torvalds 已提交
6539 6540
	int err;

6541
	if (!ops->ndo_set_mac_address)
L
Linus Torvalds 已提交
6542 6543 6544 6545 6546
		return -EOPNOTSUPP;
	if (sa->sa_family != dev->type)
		return -EINVAL;
	if (!netif_device_present(dev))
		return -ENODEV;
6547
	err = ops->ndo_set_mac_address(dev, sa);
6548 6549
	if (err)
		return err;
J
Jiri Pirko 已提交
6550
	dev->addr_assign_type = NET_ADDR_SET;
6551
	call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
6552
	add_device_randomness(dev->dev_addr, dev->addr_len);
6553
	return 0;
L
Linus Torvalds 已提交
6554
}
E
Eric Dumazet 已提交
6555
EXPORT_SYMBOL(dev_set_mac_address);
L
Linus Torvalds 已提交
6556

J
Jiri Pirko 已提交
6557 6558 6559
/**
 *	dev_change_carrier - Change device carrier
 *	@dev: device
6560
 *	@new_carrier: new value
J
Jiri Pirko 已提交
6561 6562 6563 6564 6565 6566 6567 6568 6569 6570 6571 6572 6573 6574 6575
 *
 *	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);

6576 6577 6578 6579 6580 6581 6582 6583
/**
 *	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,
6584
			 struct netdev_phys_item_id *ppid)
6585 6586 6587 6588 6589 6590 6591 6592 6593
{
	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);

6594 6595 6596 6597
/**
 *	dev_get_phys_port_name - Get device physical port name
 *	@dev: device
 *	@name: port name
6598
 *	@len: limit of bytes to copy to name
6599 6600 6601 6602 6603 6604 6605 6606 6607 6608 6609 6610 6611 6612
 *
 *	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);

6613 6614 6615 6616 6617 6618 6619 6620 6621 6622 6623 6624 6625 6626 6627 6628 6629 6630 6631 6632
/**
 *	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);

6633 6634 6635 6636 6637 6638 6639 6640 6641 6642 6643 6644 6645 6646 6647 6648 6649 6650 6651 6652 6653 6654 6655 6656 6657 6658 6659 6660 6661 6662 6663 6664
/**
 *	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
6665 6666
/**
 *	dev_new_index	-	allocate an ifindex
6667
 *	@net: the applicable net namespace
L
Linus Torvalds 已提交
6668 6669 6670 6671 6672
 *
 *	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.
 */
6673
static int dev_new_index(struct net *net)
L
Linus Torvalds 已提交
6674
{
6675
	int ifindex = net->ifindex;
L
Linus Torvalds 已提交
6676 6677 6678
	for (;;) {
		if (++ifindex <= 0)
			ifindex = 1;
6679
		if (!__dev_get_by_index(net, ifindex))
6680
			return net->ifindex = ifindex;
L
Linus Torvalds 已提交
6681 6682 6683 6684
	}
}

/* Delayed registration/unregisteration */
6685
static LIST_HEAD(net_todo_list);
6686
DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
L
Linus Torvalds 已提交
6687

6688
static void net_set_todo(struct net_device *dev)
L
Linus Torvalds 已提交
6689 6690
{
	list_add_tail(&dev->todo_list, &net_todo_list);
6691
	dev_net(dev)->dev_unreg_count++;
L
Linus Torvalds 已提交
6692 6693
}

6694
static void rollback_registered_many(struct list_head *head)
6695
{
6696
	struct net_device *dev, *tmp;
6697
	LIST_HEAD(close_head);
6698

6699 6700 6701
	BUG_ON(dev_boot_phase);
	ASSERT_RTNL();

6702
	list_for_each_entry_safe(dev, tmp, head, unreg_list) {
6703
		/* Some devices call without registering
6704 6705
		 * for initialization unwind. Remove those
		 * devices and proceed with the remaining.
6706 6707
		 */
		if (dev->reg_state == NETREG_UNINITIALIZED) {
6708 6709
			pr_debug("unregister_netdevice: device %s/%p never was registered\n",
				 dev->name, dev);
6710

6711
			WARN_ON(1);
6712 6713
			list_del(&dev->unreg_list);
			continue;
6714
		}
6715
		dev->dismantle = true;
6716
		BUG_ON(dev->reg_state != NETREG_REGISTERED);
6717
	}
6718

6719
	/* If device is running, close it first. */
6720 6721
	list_for_each_entry(dev, head, unreg_list)
		list_add_tail(&dev->close_list, &close_head);
6722
	dev_close_many(&close_head, true);
6723

6724
	list_for_each_entry(dev, head, unreg_list) {
6725 6726
		/* And unlink it from device chain. */
		unlist_netdevice(dev);
6727

6728 6729
		dev->reg_state = NETREG_UNREGISTERING;
	}
6730
	flush_all_backlogs();
6731 6732 6733

	synchronize_net();

6734
	list_for_each_entry(dev, head, unreg_list) {
6735 6736
		struct sk_buff *skb = NULL;

6737 6738
		/* Shutdown queueing discipline. */
		dev_shutdown(dev);
6739 6740


6741 6742 6743 6744
		/* Notify protocols, that we are about to destroy
		   this device. They should clean all the things.
		*/
		call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
6745

6746 6747 6748 6749 6750
		if (!dev->rtnl_link_ops ||
		    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
			skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U,
						     GFP_KERNEL);

6751 6752 6753
		/*
		 *	Flush the unicast and multicast chains
		 */
6754
		dev_uc_flush(dev);
6755
		dev_mc_flush(dev);
6756

6757 6758
		if (dev->netdev_ops->ndo_uninit)
			dev->netdev_ops->ndo_uninit(dev);
6759

6760 6761
		if (skb)
			rtmsg_ifinfo_send(skb, dev, GFP_KERNEL);
6762

J
Jiri Pirko 已提交
6763 6764
		/* Notifier chain MUST detach us all upper devices. */
		WARN_ON(netdev_has_any_upper_dev(dev));
6765
		WARN_ON(netdev_has_any_lower_dev(dev));
6766

6767 6768
		/* Remove entries from kobject tree */
		netdev_unregister_kobject(dev);
6769 6770 6771 6772
#ifdef CONFIG_XPS
		/* Remove XPS queueing entries */
		netif_reset_xps_queues_gt(dev, 0);
#endif
6773
	}
6774

6775
	synchronize_net();
6776

6777
	list_for_each_entry(dev, head, unreg_list)
6778 6779 6780 6781 6782 6783 6784 6785 6786
		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
6787
	list_del(&single);
6788 6789
}

6790 6791 6792 6793 6794
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;
6795
	int feature_bit;
6796

6797 6798
	for_each_netdev_feature(&upper_disables, feature_bit) {
		feature = __NETIF_F_BIT(feature_bit);
6799 6800 6801 6802 6803 6804 6805 6806 6807 6808 6809 6810 6811 6812 6813 6814
		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;
6815
	int feature_bit;
6816

6817 6818
	for_each_netdev_feature(&upper_disables, feature_bit) {
		feature = __NETIF_F_BIT(feature_bit);
6819 6820 6821 6822 6823 6824 6825 6826 6827 6828 6829 6830 6831
		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);
		}
	}
}

6832 6833
static netdev_features_t netdev_fix_features(struct net_device *dev,
	netdev_features_t features)
6834
{
6835 6836 6837
	/* Fix illegal checksum combinations */
	if ((features & NETIF_F_HW_CSUM) &&
	    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
6838
		netdev_warn(dev, "mixed HW and IP checksum settings.\n");
6839 6840 6841
		features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
	}

6842
	/* TSO requires that SG is present as well. */
6843
	if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
6844
		netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
6845
		features &= ~NETIF_F_ALL_TSO;
6846 6847
	}

6848 6849 6850 6851 6852 6853 6854 6855 6856 6857 6858 6859 6860
	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;
	}

6861 6862 6863 6864
	/* 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;

6865 6866 6867 6868
	/* TSO ECN requires that TSO is present as well. */
	if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
		features &= ~NETIF_F_TSO_ECN;

6869 6870
	/* Software GSO depends on SG. */
	if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
6871
		netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
6872 6873 6874
		features &= ~NETIF_F_GSO;
	}

6875
	/* UFO needs SG and checksumming */
6876
	if (features & NETIF_F_UFO) {
6877
		/* maybe split UFO into V4 and V6? */
6878 6879 6880
		if (!(features & NETIF_F_HW_CSUM) &&
		    ((features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) !=
		     (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM))) {
6881
			netdev_dbg(dev,
6882
				"Dropping NETIF_F_UFO since no checksum offload features.\n");
6883 6884 6885 6886
			features &= ~NETIF_F_UFO;
		}

		if (!(features & NETIF_F_SG)) {
6887
			netdev_dbg(dev,
6888
				"Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
6889 6890 6891 6892
			features &= ~NETIF_F_UFO;
		}
	}

6893 6894 6895 6896 6897 6898 6899 6900
	/* 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
6901 6902 6903 6904 6905 6906 6907
#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;

6908 6909 6910
	return features;
}

6911
int __netdev_update_features(struct net_device *dev)
6912
{
6913
	struct net_device *upper, *lower;
6914
	netdev_features_t features;
6915
	struct list_head *iter;
6916
	int err = -1;
6917

6918 6919
	ASSERT_RTNL();

6920 6921 6922 6923 6924 6925 6926 6927
	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);

6928 6929 6930 6931
	/* 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);

6932
	if (dev->features == features)
6933
		goto sync_lower;
6934

6935 6936
	netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
		&dev->features, &features);
6937 6938 6939

	if (dev->netdev_ops->ndo_set_features)
		err = dev->netdev_ops->ndo_set_features(dev, features);
6940 6941
	else
		err = 0;
6942

6943
	if (unlikely(err < 0)) {
6944
		netdev_err(dev,
6945 6946
			"set_features() failed (%d); wanted %pNF, left %pNF\n",
			err, &features, &dev->features);
6947 6948 6949 6950
		/* return non-0 since some features might have changed and
		 * it's better to fire a spurious notification than miss it
		 */
		return -1;
6951 6952
	}

6953
sync_lower:
6954 6955 6956 6957 6958 6959
	/* 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);

6960 6961 6962
	if (!err)
		dev->features = features;

6963
	return err < 0 ? 0 : 1;
6964 6965
}

6966 6967 6968 6969 6970 6971 6972 6973
/**
 *	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.
 */
6974 6975 6976 6977
void netdev_update_features(struct net_device *dev)
{
	if (__netdev_update_features(dev))
		netdev_features_change(dev);
6978 6979 6980
}
EXPORT_SYMBOL(netdev_update_features);

6981 6982 6983 6984 6985 6986 6987 6988 6989 6990 6991 6992 6993 6994 6995 6996 6997
/**
 *	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);

6998 6999 7000 7001 7002 7003 7004 7005 7006 7007 7008 7009 7010 7011 7012 7013 7014 7015 7016 7017 7018 7019 7020 7021 7022 7023 7024
/**
 *	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);

7025
#ifdef CONFIG_SYSFS
7026 7027 7028
static int netif_alloc_rx_queues(struct net_device *dev)
{
	unsigned int i, count = dev->num_rx_queues;
T
Tom Herbert 已提交
7029
	struct netdev_rx_queue *rx;
7030
	size_t sz = count * sizeof(*rx);
7031

T
Tom Herbert 已提交
7032
	BUG_ON(count < 1);
7033

7034 7035 7036 7037 7038 7039
	rx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!rx) {
		rx = vzalloc(sz);
		if (!rx)
			return -ENOMEM;
	}
T
Tom Herbert 已提交
7040 7041 7042
	dev->_rx = rx;

	for (i = 0; i < count; i++)
T
Tom Herbert 已提交
7043
		rx[i].dev = dev;
7044 7045
	return 0;
}
T
Tom Herbert 已提交
7046
#endif
7047

C
Changli Gao 已提交
7048 7049 7050 7051 7052 7053 7054
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;
7055
	netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
C
Changli Gao 已提交
7056
	queue->dev = dev;
T
Tom Herbert 已提交
7057 7058 7059
#ifdef CONFIG_BQL
	dql_init(&queue->dql, HZ);
#endif
C
Changli Gao 已提交
7060 7061
}

7062 7063
static void netif_free_tx_queues(struct net_device *dev)
{
W
WANG Cong 已提交
7064
	kvfree(dev->_tx);
7065 7066
}

7067 7068 7069 7070
static int netif_alloc_netdev_queues(struct net_device *dev)
{
	unsigned int count = dev->num_tx_queues;
	struct netdev_queue *tx;
7071
	size_t sz = count * sizeof(*tx);
7072

7073 7074
	if (count < 1 || count > 0xffff)
		return -EINVAL;
7075

7076 7077 7078 7079 7080 7081
	tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!tx) {
		tx = vzalloc(sz);
		if (!tx)
			return -ENOMEM;
	}
7082
	dev->_tx = tx;
T
Tom Herbert 已提交
7083

7084 7085
	netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
	spin_lock_init(&dev->tx_global_lock);
C
Changli Gao 已提交
7086 7087

	return 0;
7088 7089
}

7090 7091 7092 7093 7094 7095 7096 7097 7098 7099 7100
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
7101 7102 7103 7104 7105 7106 7107 7108 7109 7110 7111 7112 7113 7114 7115 7116 7117 7118 7119 7120
/**
 *	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;
7121
	struct net *net = dev_net(dev);
L
Linus Torvalds 已提交
7122 7123 7124 7125

	BUG_ON(dev_boot_phase);
	ASSERT_RTNL();

7126 7127
	might_sleep();

L
Linus Torvalds 已提交
7128 7129
	/* When net_device's are persistent, this will be fatal. */
	BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
7130
	BUG_ON(!net);
L
Linus Torvalds 已提交
7131

7132
	spin_lock_init(&dev->addr_list_lock);
7133
	netdev_set_addr_lockdep_class(dev);
L
Linus Torvalds 已提交
7134

7135
	ret = dev_get_valid_name(net, dev, dev->name);
7136 7137 7138
	if (ret < 0)
		goto out;

L
Linus Torvalds 已提交
7139
	/* Init, if this function is available */
7140 7141
	if (dev->netdev_ops->ndo_init) {
		ret = dev->netdev_ops->ndo_init(dev);
L
Linus Torvalds 已提交
7142 7143 7144
		if (ret) {
			if (ret > 0)
				ret = -EIO;
7145
			goto out;
L
Linus Torvalds 已提交
7146 7147
		}
	}
7148

7149 7150
	if (((dev->hw_features | dev->features) &
	     NETIF_F_HW_VLAN_CTAG_FILTER) &&
7151 7152 7153 7154 7155 7156 7157
	    (!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;
	}

7158 7159 7160 7161 7162 7163
	ret = -EBUSY;
	if (!dev->ifindex)
		dev->ifindex = dev_new_index(net);
	else if (__dev_get_by_index(net, dev->ifindex))
		goto err_uninit;

7164 7165 7166 7167
	/* Transfer changeable features to wanted_features and enable
	 * software offloads (GSO and GRO).
	 */
	dev->hw_features |= NETIF_F_SOFT_FEATURES;
7168 7169
	dev->features |= NETIF_F_SOFT_FEATURES;
	dev->wanted_features = dev->features & dev->hw_features;
L
Linus Torvalds 已提交
7170

7171
	if (!(dev->flags & IFF_LOOPBACK))
7172
		dev->hw_features |= NETIF_F_NOCACHE_COPY;
7173

7174 7175 7176 7177 7178
	/* 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.
	 */
7179 7180
	if (dev->hw_features & NETIF_F_TSO)
		dev->hw_features |= NETIF_F_TSO_MANGLEID;
7181 7182 7183 7184 7185 7186
	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;
7187

7188
	/* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
7189
	 */
7190
	dev->vlan_features |= NETIF_F_HIGHDMA;
7191

7192 7193
	/* Make NETIF_F_SG inheritable to tunnel devices.
	 */
7194
	dev->hw_enc_features |= NETIF_F_SG | NETIF_F_GSO_PARTIAL;
7195

S
Simon Horman 已提交
7196 7197 7198 7199
	/* Make NETIF_F_SG inheritable to MPLS.
	 */
	dev->mpls_features |= NETIF_F_SG;

7200 7201 7202 7203 7204
	ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
	ret = notifier_to_errno(ret);
	if (ret)
		goto err_uninit;

7205
	ret = netdev_register_kobject(dev);
7206
	if (ret)
7207
		goto err_uninit;
7208 7209
	dev->reg_state = NETREG_REGISTERED;

7210
	__netdev_update_features(dev);
7211

L
Linus Torvalds 已提交
7212 7213 7214 7215 7216 7217 7218
	/*
	 *	Default initial state at registry is that the
	 *	device is present.
	 */

	set_bit(__LINK_STATE_PRESENT, &dev->state);

7219 7220
	linkwatch_init_dev(dev);

L
Linus Torvalds 已提交
7221 7222
	dev_init_scheduler(dev);
	dev_hold(dev);
7223
	list_netdevice(dev);
7224
	add_device_randomness(dev->dev_addr, dev->addr_len);
L
Linus Torvalds 已提交
7225

7226 7227 7228 7229 7230 7231 7232
	/* 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
7233
	/* Notify protocols, that a new device appeared. */
7234
	ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
7235
	ret = notifier_to_errno(ret);
7236 7237 7238 7239
	if (ret) {
		rollback_registered(dev);
		dev->reg_state = NETREG_UNREGISTERED;
	}
7240 7241 7242 7243
	/*
	 *	Prevent userspace races by waiting until the network
	 *	device is fully setup before sending notifications.
	 */
7244 7245
	if (!dev->rtnl_link_ops ||
	    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
7246
		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
L
Linus Torvalds 已提交
7247 7248 7249

out:
	return ret;
7250 7251

err_uninit:
7252 7253
	if (dev->netdev_ops->ndo_uninit)
		dev->netdev_ops->ndo_uninit(dev);
7254
	goto out;
L
Linus Torvalds 已提交
7255
}
E
Eric Dumazet 已提交
7256
EXPORT_SYMBOL(register_netdevice);
L
Linus Torvalds 已提交
7257

7258 7259 7260 7261 7262 7263 7264 7265 7266 7267 7268 7269 7270 7271 7272 7273 7274 7275 7276 7277 7278 7279 7280 7281 7282 7283 7284 7285 7286 7287 7288
/**
 *	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
7289 7290 7291 7292 7293
	/* Note : We dont allocate pcpu_refcnt for dummy devices,
	 * because users of this 'device' dont need to change
	 * its refcount.
	 */

7294 7295 7296 7297 7298
	return 0;
}
EXPORT_SYMBOL_GPL(init_dummy_netdev);


L
Linus Torvalds 已提交
7299 7300 7301 7302 7303 7304 7305 7306 7307
/**
 *	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.
 *
7308
 *	This is a wrapper around register_netdevice that takes the rtnl semaphore
L
Linus Torvalds 已提交
7309 7310 7311 7312 7313 7314 7315 7316 7317 7318 7319 7320 7321 7322
 *	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
7323 7324 7325 7326 7327 7328 7329 7330 7331 7332
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);

7333
/**
L
Linus Torvalds 已提交
7334
 * netdev_wait_allrefs - wait until all references are gone.
7335
 * @dev: target net_device
L
Linus Torvalds 已提交
7336 7337 7338 7339 7340 7341 7342
 *
 * 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
7343
 * call dev_put.
L
Linus Torvalds 已提交
7344 7345 7346 7347
 */
static void netdev_wait_allrefs(struct net_device *dev)
{
	unsigned long rebroadcast_time, warning_time;
E
Eric Dumazet 已提交
7348
	int refcnt;
L
Linus Torvalds 已提交
7349

7350 7351
	linkwatch_forget_dev(dev);

L
Linus Torvalds 已提交
7352
	rebroadcast_time = warning_time = jiffies;
E
Eric Dumazet 已提交
7353 7354 7355
	refcnt = netdev_refcnt_read(dev);

	while (refcnt != 0) {
L
Linus Torvalds 已提交
7356
		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
7357
			rtnl_lock();
L
Linus Torvalds 已提交
7358 7359

			/* Rebroadcast unregister notification */
7360
			call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
L
Linus Torvalds 已提交
7361

7362
			__rtnl_unlock();
7363
			rcu_barrier();
7364 7365
			rtnl_lock();

7366
			call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
L
Linus Torvalds 已提交
7367 7368 7369 7370 7371 7372 7373 7374 7375 7376 7377
			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();
			}

7378
			__rtnl_unlock();
L
Linus Torvalds 已提交
7379 7380 7381 7382 7383 7384

			rebroadcast_time = jiffies;
		}

		msleep(250);

E
Eric Dumazet 已提交
7385 7386
		refcnt = netdev_refcnt_read(dev);

L
Linus Torvalds 已提交
7387
		if (time_after(jiffies, warning_time + 10 * HZ)) {
7388 7389
			pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
				 dev->name, refcnt);
L
Linus Torvalds 已提交
7390 7391 7392 7393 7394 7395 7396 7397 7398 7399 7400 7401 7402 7403 7404 7405 7406 7407 7408
			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
7409
 * We are invoked by rtnl_unlock().
L
Linus Torvalds 已提交
7410
 * This allows us to deal with problems:
7411
 * 1) We can delete sysfs objects which invoke hotplug
L
Linus Torvalds 已提交
7412 7413 7414
 *    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
7415 7416 7417
 *
 * 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
7418 7419 7420
 */
void netdev_run_todo(void)
{
7421
	struct list_head list;
L
Linus Torvalds 已提交
7422 7423

	/* Snapshot list, allow later requests */
7424
	list_replace_init(&net_todo_list, &list);
H
Herbert Xu 已提交
7425 7426

	__rtnl_unlock();
7427

7428 7429

	/* Wait for rcu callbacks to finish before next phase */
7430 7431 7432
	if (!list_empty(&list))
		rcu_barrier();

L
Linus Torvalds 已提交
7433 7434
	while (!list_empty(&list)) {
		struct net_device *dev
7435
			= list_first_entry(&list, struct net_device, todo_list);
L
Linus Torvalds 已提交
7436 7437
		list_del(&dev->todo_list);

7438
		rtnl_lock();
7439
		call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
7440
		__rtnl_unlock();
7441

7442
		if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
7443
			pr_err("network todo '%s' but state %d\n",
7444 7445 7446 7447
			       dev->name, dev->reg_state);
			dump_stack();
			continue;
		}
L
Linus Torvalds 已提交
7448

7449
		dev->reg_state = NETREG_UNREGISTERED;
L
Linus Torvalds 已提交
7450

7451
		netdev_wait_allrefs(dev);
L
Linus Torvalds 已提交
7452

7453
		/* paranoia */
E
Eric Dumazet 已提交
7454
		BUG_ON(netdev_refcnt_read(dev));
7455 7456
		BUG_ON(!list_empty(&dev->ptype_all));
		BUG_ON(!list_empty(&dev->ptype_specific));
7457 7458
		WARN_ON(rcu_access_pointer(dev->ip_ptr));
		WARN_ON(rcu_access_pointer(dev->ip6_ptr));
7459
		WARN_ON(dev->dn_ptr);
L
Linus Torvalds 已提交
7460

7461 7462
		if (dev->destructor)
			dev->destructor(dev);
7463

7464 7465 7466 7467 7468 7469
		/* Report a network device has been unregistered */
		rtnl_lock();
		dev_net(dev)->dev_unreg_count--;
		__rtnl_unlock();
		wake_up(&netdev_unregistering_wq);

7470 7471
		/* Free network device */
		kobject_put(&dev->dev.kobj);
L
Linus Torvalds 已提交
7472 7473 7474
	}
}

7475 7476 7477 7478
/* 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.
7479
 */
7480 7481
void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
			     const struct net_device_stats *netdev_stats)
7482 7483
{
#if BITS_PER_LONG == 64
7484
	BUILD_BUG_ON(sizeof(*stats64) < sizeof(*netdev_stats));
7485
	memcpy(stats64, netdev_stats, sizeof(*stats64));
7486 7487 7488
	/* zero out counters that only exist in rtnl_link_stats64 */
	memset((char *)stats64 + sizeof(*netdev_stats), 0,
	       sizeof(*stats64) - sizeof(*netdev_stats));
7489
#else
7490
	size_t i, n = sizeof(*netdev_stats) / sizeof(unsigned long);
7491 7492 7493
	const unsigned long *src = (const unsigned long *)netdev_stats;
	u64 *dst = (u64 *)stats64;

7494
	BUILD_BUG_ON(n > sizeof(*stats64) / sizeof(u64));
7495 7496
	for (i = 0; i < n; i++)
		dst[i] = src[i];
7497 7498 7499
	/* zero out counters that only exist in rtnl_link_stats64 */
	memset((char *)stats64 + n * sizeof(u64), 0,
	       sizeof(*stats64) - n * sizeof(u64));
7500 7501
#endif
}
7502
EXPORT_SYMBOL(netdev_stats_to_stats64);
7503

7504 7505 7506
/**
 *	dev_get_stats	- get network device statistics
 *	@dev: device to get statistics from
7507
 *	@storage: place to store stats
7508
 *
7509 7510 7511 7512
 *	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.
7513
 */
7514 7515
struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
					struct rtnl_link_stats64 *storage)
7516
{
7517 7518
	const struct net_device_ops *ops = dev->netdev_ops;

7519 7520
	if (ops->ndo_get_stats64) {
		memset(storage, 0, sizeof(*storage));
7521 7522
		ops->ndo_get_stats64(dev, storage);
	} else if (ops->ndo_get_stats) {
7523
		netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
7524 7525
	} else {
		netdev_stats_to_stats64(storage, &dev->stats);
7526
	}
7527
	storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
7528
	storage->tx_dropped += atomic_long_read(&dev->tx_dropped);
7529
	storage->rx_nohandler += atomic_long_read(&dev->rx_nohandler);
7530
	return storage;
R
Rusty Russell 已提交
7531
}
7532
EXPORT_SYMBOL(dev_get_stats);
R
Rusty Russell 已提交
7533

7534
struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
7535
{
7536
	struct netdev_queue *queue = dev_ingress_queue(dev);
7537

7538 7539 7540 7541 7542 7543 7544
#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
7545
	RCU_INIT_POINTER(queue->qdisc, &noop_qdisc);
7546 7547 7548 7549
	queue->qdisc_sleeping = &noop_qdisc;
	rcu_assign_pointer(dev->ingress_queue, queue);
#endif
	return queue;
7550 7551
}

7552 7553
static const struct ethtool_ops default_ethtool_ops;

7554 7555 7556 7557 7558 7559 7560 7561
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);

7562 7563 7564 7565
void netdev_freemem(struct net_device *dev)
{
	char *addr = (char *)dev - dev->padded;

W
WANG Cong 已提交
7566
	kvfree(addr);
7567 7568
}

L
Linus Torvalds 已提交
7569
/**
T
Tom Herbert 已提交
7570
 *	alloc_netdev_mqs - allocate network device
7571 7572 7573 7574 7575 7576
 *	@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
7577 7578
 *
 *	Allocates a struct net_device with private data area for driver use
L
Li Zhong 已提交
7579
 *	and performs basic initialization.  Also allocates subqueue structs
T
Tom Herbert 已提交
7580
 *	for each queue on the device.
L
Linus Torvalds 已提交
7581
 */
T
Tom Herbert 已提交
7582
struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
7583
		unsigned char name_assign_type,
T
Tom Herbert 已提交
7584 7585
		void (*setup)(struct net_device *),
		unsigned int txqs, unsigned int rxqs)
L
Linus Torvalds 已提交
7586 7587
{
	struct net_device *dev;
7588
	size_t alloc_size;
7589
	struct net_device *p;
L
Linus Torvalds 已提交
7590

7591 7592
	BUG_ON(strlen(name) >= sizeof(dev->name));

T
Tom Herbert 已提交
7593
	if (txqs < 1) {
7594
		pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
7595 7596 7597
		return NULL;
	}

7598
#ifdef CONFIG_SYSFS
T
Tom Herbert 已提交
7599
	if (rxqs < 1) {
7600
		pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
T
Tom Herbert 已提交
7601 7602 7603 7604
		return NULL;
	}
#endif

7605
	alloc_size = sizeof(struct net_device);
7606 7607
	if (sizeof_priv) {
		/* ensure 32-byte alignment of private area */
7608
		alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
7609 7610 7611
		alloc_size += sizeof_priv;
	}
	/* ensure 32-byte alignment of whole construct */
7612
	alloc_size += NETDEV_ALIGN - 1;
L
Linus Torvalds 已提交
7613

7614 7615 7616
	p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
	if (!p)
		p = vzalloc(alloc_size);
7617
	if (!p)
L
Linus Torvalds 已提交
7618 7619
		return NULL;

7620
	dev = PTR_ALIGN(p, NETDEV_ALIGN);
L
Linus Torvalds 已提交
7621
	dev->padded = (char *)dev - (char *)p;
7622

E
Eric Dumazet 已提交
7623 7624
	dev->pcpu_refcnt = alloc_percpu(int);
	if (!dev->pcpu_refcnt)
7625
		goto free_dev;
7626 7627

	if (dev_addr_init(dev))
E
Eric Dumazet 已提交
7628
		goto free_pcpu;
7629

7630
	dev_mc_init(dev);
7631
	dev_uc_init(dev);
J
Jiri Pirko 已提交
7632

7633
	dev_net_set(dev, &init_net);
L
Linus Torvalds 已提交
7634

7635
	dev->gso_max_size = GSO_MAX_SIZE;
7636
	dev->gso_max_segs = GSO_MAX_SEGS;
7637 7638 7639

	INIT_LIST_HEAD(&dev->napi_list);
	INIT_LIST_HEAD(&dev->unreg_list);
7640
	INIT_LIST_HEAD(&dev->close_list);
7641
	INIT_LIST_HEAD(&dev->link_watch_list);
7642 7643
	INIT_LIST_HEAD(&dev->adj_list.upper);
	INIT_LIST_HEAD(&dev->adj_list.lower);
7644 7645
	INIT_LIST_HEAD(&dev->ptype_all);
	INIT_LIST_HEAD(&dev->ptype_specific);
7646 7647 7648
#ifdef CONFIG_NET_SCHED
	hash_init(dev->qdisc_hash);
#endif
7649
	dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM;
7650 7651
	setup(dev);

7652
	if (!dev->tx_queue_len) {
7653
		dev->priv_flags |= IFF_NO_QUEUE;
7654
		dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
7655
	}
7656

T
Tom Herbert 已提交
7657 7658
	dev->num_tx_queues = txqs;
	dev->real_num_tx_queues = txqs;
7659
	if (netif_alloc_netdev_queues(dev))
7660
		goto free_all;
7661

7662
#ifdef CONFIG_SYSFS
T
Tom Herbert 已提交
7663 7664
	dev->num_rx_queues = rxqs;
	dev->real_num_rx_queues = rxqs;
T
Tom Herbert 已提交
7665
	if (netif_alloc_rx_queues(dev))
7666
		goto free_all;
E
Eric Dumazet 已提交
7667
#endif
T
Tom Herbert 已提交
7668

L
Linus Torvalds 已提交
7669
	strcpy(dev->name, name);
7670
	dev->name_assign_type = name_assign_type;
7671
	dev->group = INIT_NETDEV_GROUP;
7672 7673
	if (!dev->ethtool_ops)
		dev->ethtool_ops = &default_ethtool_ops;
7674 7675 7676

	nf_hook_ingress_init(dev);

L
Linus Torvalds 已提交
7677
	return dev;
7678

7679 7680 7681 7682
free_all:
	free_netdev(dev);
	return NULL;

E
Eric Dumazet 已提交
7683 7684
free_pcpu:
	free_percpu(dev->pcpu_refcnt);
7685 7686
free_dev:
	netdev_freemem(dev);
7687
	return NULL;
L
Linus Torvalds 已提交
7688
}
T
Tom Herbert 已提交
7689
EXPORT_SYMBOL(alloc_netdev_mqs);
L
Linus Torvalds 已提交
7690 7691 7692 7693 7694

/**
 *	free_netdev - free network device
 *	@dev: device
 *
7695 7696
 *	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
7697
 *	If this is the last reference then it will be freed.
7698
 *	Must be called in process context.
L
Linus Torvalds 已提交
7699 7700 7701
 */
void free_netdev(struct net_device *dev)
{
7702 7703
	struct napi_struct *p, *n;

7704
	might_sleep();
7705
	netif_free_tx_queues(dev);
7706
#ifdef CONFIG_SYSFS
7707
	kvfree(dev->_rx);
T
Tom Herbert 已提交
7708
#endif
7709

7710
	kfree(rcu_dereference_protected(dev->ingress_queue, 1));
7711

7712 7713 7714
	/* Flush device addresses */
	dev_addr_flush(dev);

7715 7716 7717
	list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
		netif_napi_del(p);

E
Eric Dumazet 已提交
7718 7719 7720
	free_percpu(dev->pcpu_refcnt);
	dev->pcpu_refcnt = NULL;

S
Stephen Hemminger 已提交
7721
	/*  Compatibility with error handling in drivers */
L
Linus Torvalds 已提交
7722
	if (dev->reg_state == NETREG_UNINITIALIZED) {
7723
		netdev_freemem(dev);
L
Linus Torvalds 已提交
7724 7725 7726 7727 7728 7729
		return;
	}

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

7730 7731
	/* will free via device release */
	put_device(&dev->dev);
L
Linus Torvalds 已提交
7732
}
E
Eric Dumazet 已提交
7733
EXPORT_SYMBOL(free_netdev);
7734

7735 7736 7737 7738 7739 7740
/**
 *	synchronize_net -  Synchronize with packet receive processing
 *
 *	Wait for packets currently being received to be done.
 *	Does not block later packets from starting.
 */
7741
void synchronize_net(void)
L
Linus Torvalds 已提交
7742 7743
{
	might_sleep();
7744 7745 7746 7747
	if (rtnl_is_locked())
		synchronize_rcu_expedited();
	else
		synchronize_rcu();
L
Linus Torvalds 已提交
7748
}
E
Eric Dumazet 已提交
7749
EXPORT_SYMBOL(synchronize_net);
L
Linus Torvalds 已提交
7750 7751

/**
7752
 *	unregister_netdevice_queue - remove device from the kernel
L
Linus Torvalds 已提交
7753
 *	@dev: device
7754
 *	@head: list
7755
 *
L
Linus Torvalds 已提交
7756
 *	This function shuts down a device interface and removes it
7757
 *	from the kernel tables.
7758
 *	If head not NULL, device is queued to be unregistered later.
L
Linus Torvalds 已提交
7759 7760 7761 7762 7763
 *
 *	Callers must hold the rtnl semaphore.  You may want
 *	unregister_netdev() instead of this.
 */

7764
void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
L
Linus Torvalds 已提交
7765
{
7766 7767
	ASSERT_RTNL();

7768
	if (head) {
7769
		list_move_tail(&dev->unreg_list, head);
7770 7771 7772 7773 7774
	} else {
		rollback_registered(dev);
		/* Finish processing unregister after unlock */
		net_set_todo(dev);
	}
L
Linus Torvalds 已提交
7775
}
7776
EXPORT_SYMBOL(unregister_netdevice_queue);
L
Linus Torvalds 已提交
7777

7778 7779 7780
/**
 *	unregister_netdevice_many - unregister many devices
 *	@head: list of devices
7781 7782 7783
 *
 *  Note: As most callers use a stack allocated list_head,
 *  we force a list_del() to make sure stack wont be corrupted later.
7784 7785 7786 7787 7788 7789 7790 7791 7792
 */
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);
7793
		list_del(head);
7794 7795
	}
}
7796
EXPORT_SYMBOL(unregister_netdevice_many);
7797

L
Linus Torvalds 已提交
7798 7799 7800 7801 7802
/**
 *	unregister_netdev - remove device from the kernel
 *	@dev: device
 *
 *	This function shuts down a device interface and removes it
7803
 *	from the kernel tables.
L
Linus Torvalds 已提交
7804 7805 7806 7807 7808 7809 7810 7811 7812 7813 7814 7815 7816
 *
 *	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);

7817 7818 7819 7820 7821 7822 7823 7824 7825 7826 7827 7828 7829 7830 7831 7832 7833 7834 7835 7836 7837 7838 7839 7840 7841 7842 7843 7844 7845 7846 7847
/**
 *	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;
7848
	if (net_eq(dev_net(dev), net))
7849 7850 7851 7852 7853 7854
		goto out;

	/* Pick the destination device name, and ensure
	 * we can use it in the destination network namespace.
	 */
	err = -EEXIST;
7855
	if (__dev_get_by_name(net, dev->name)) {
7856 7857 7858
		/* We get here if we can't use the current device name */
		if (!pat)
			goto out;
7859
		if (dev_get_valid_name(net, dev, pat) < 0)
7860 7861 7862 7863 7864 7865 7866 7867
			goto out;
	}

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

	/* If device is running close it first. */
7868
	dev_close(dev);
7869 7870 7871 7872 7873 7874 7875 7876 7877 7878 7879 7880

	/* 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.
7881 7882 7883 7884

	   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.
7885 7886
	*/
	call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
7887 7888
	rcu_barrier();
	call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
7889
	rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
7890 7891 7892 7893

	/*
	 *	Flush the unicast and multicast chains
	 */
7894
	dev_uc_flush(dev);
7895
	dev_mc_flush(dev);
7896

7897 7898
	/* Send a netdev-removed uevent to the old namespace */
	kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
7899
	netdev_adjacent_del_links(dev);
7900

7901
	/* Actually switch the network namespace */
7902
	dev_net_set(dev, net);
7903 7904

	/* If there is an ifindex conflict assign a new one */
7905
	if (__dev_get_by_index(net, dev->ifindex))
7906 7907
		dev->ifindex = dev_new_index(net);

7908 7909
	/* Send a netdev-add uevent to the new namespace */
	kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
7910
	netdev_adjacent_add_links(dev);
7911

7912
	/* Fixup kobjects */
7913
	err = device_rename(&dev->dev, dev->name);
7914
	WARN_ON(err);
7915 7916 7917 7918 7919 7920 7921

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

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

7922 7923 7924 7925
	/*
	 *	Prevent userspace races by waiting until the network
	 *	device is fully setup before sending notifications.
	 */
7926
	rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
7927

7928 7929 7930 7931 7932
	synchronize_net();
	err = 0;
out:
	return err;
}
7933
EXPORT_SYMBOL_GPL(dev_change_net_namespace);
7934

L
Linus Torvalds 已提交
7935 7936 7937 7938 7939 7940 7941 7942 7943
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;

7944
	if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
L
Linus Torvalds 已提交
7945 7946 7947 7948 7949 7950 7951 7952 7953 7954 7955 7956 7957 7958 7959 7960
		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. */
7961 7962 7963 7964 7965 7966
	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
7967 7968 7969 7970 7971 7972 7973 7974 7975 7976 7977 7978 7979 7980
	/* 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);
7981
	}
L
Linus Torvalds 已提交
7982 7983 7984 7985 7986

	raise_softirq_irqoff(NET_TX_SOFTIRQ);
	local_irq_enable();

	/* Process offline CPU's input_pkt_queue */
7987
	while ((skb = __skb_dequeue(&oldsd->process_queue))) {
7988
		netif_rx_ni(skb);
7989
		input_queue_head_incr(oldsd);
T
Tom Herbert 已提交
7990
	}
E
Eric Dumazet 已提交
7991
	while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
7992
		netif_rx_ni(skb);
7993 7994
		input_queue_head_incr(oldsd);
	}
L
Linus Torvalds 已提交
7995 7996 7997 7998 7999

	return NOTIFY_OK;
}


8000
/**
8001 8002 8003 8004
 *	netdev_increment_features - increment feature set by one
 *	@all: current feature set
 *	@one: new feature set
 *	@mask: mask feature set
8005 8006
 *
 *	Computes a new feature set after adding a device with feature set
8007 8008
 *	@one to the master device with current feature set @all.  Will not
 *	enable anything that is off in @mask. Returns the new feature set.
8009
 */
8010 8011
netdev_features_t netdev_increment_features(netdev_features_t all,
	netdev_features_t one, netdev_features_t mask)
8012
{
8013
	if (mask & NETIF_F_HW_CSUM)
8014
		mask |= NETIF_F_CSUM_MASK;
8015
	mask |= NETIF_F_VLAN_CHALLENGED;
8016

8017
	all |= one & (NETIF_F_ONE_FOR_ALL | NETIF_F_CSUM_MASK) & mask;
8018
	all &= one | ~NETIF_F_ALL_FOR_ALL;
8019

8020
	/* If one device supports hw checksumming, set for all. */
8021 8022
	if (all & NETIF_F_HW_CSUM)
		all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM);
8023 8024 8025

	return all;
}
8026
EXPORT_SYMBOL(netdev_increment_features);
8027

8028
static struct hlist_head * __net_init netdev_create_hash(void)
8029 8030 8031 8032 8033 8034 8035 8036 8037 8038 8039 8040
{
	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;
}

8041
/* Initialize per network namespace state */
8042
static int __net_init netdev_init(struct net *net)
8043
{
8044 8045
	if (net != &init_net)
		INIT_LIST_HEAD(&net->dev_base_head);
8046

8047 8048 8049
	net->dev_name_head = netdev_create_hash();
	if (net->dev_name_head == NULL)
		goto err_name;
8050

8051 8052 8053
	net->dev_index_head = netdev_create_hash();
	if (net->dev_index_head == NULL)
		goto err_idx;
8054 8055

	return 0;
8056 8057 8058 8059 8060

err_idx:
	kfree(net->dev_name_head);
err_name:
	return -ENOMEM;
8061 8062
}

8063 8064 8065 8066 8067 8068
/**
 *	netdev_drivername - network driver for the device
 *	@dev: network device
 *
 *	Determine network driver for device.
 */
8069
const char *netdev_drivername(const struct net_device *dev)
8070
{
8071 8072
	const struct device_driver *driver;
	const struct device *parent;
8073
	const char *empty = "";
8074 8075 8076

	parent = dev->dev.parent;
	if (!parent)
8077
		return empty;
8078 8079 8080

	driver = parent->driver;
	if (driver && driver->name)
8081 8082
		return driver->name;
	return empty;
8083 8084
}

8085 8086
static void __netdev_printk(const char *level, const struct net_device *dev,
			    struct va_format *vaf)
8087
{
8088
	if (dev && dev->dev.parent) {
8089 8090 8091 8092 8093 8094 8095
		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);
8096
	} else if (dev) {
8097 8098
		printk("%s%s%s: %pV",
		       level, netdev_name(dev), netdev_reg_state(dev), vaf);
8099
	} else {
8100
		printk("%s(NULL net_device): %pV", level, vaf);
8101
	}
8102 8103
}

8104 8105
void netdev_printk(const char *level, const struct net_device *dev,
		   const char *format, ...)
8106 8107 8108 8109 8110 8111 8112 8113 8114
{
	struct va_format vaf;
	va_list args;

	va_start(args, format);

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

8115
	__netdev_printk(level, dev, &vaf);
8116

8117 8118 8119 8120 8121
	va_end(args);
}
EXPORT_SYMBOL(netdev_printk);

#define define_netdev_printk_level(func, level)			\
8122
void func(const struct net_device *dev, const char *fmt, ...)	\
8123 8124 8125 8126 8127 8128 8129 8130 8131
{								\
	struct va_format vaf;					\
	va_list args;						\
								\
	va_start(args, fmt);					\
								\
	vaf.fmt = fmt;						\
	vaf.va = &args;						\
								\
8132
	__netdev_printk(level, dev, &vaf);			\
8133
								\
8134 8135 8136 8137 8138 8139 8140 8141 8142 8143 8144 8145
	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);

8146
static void __net_exit netdev_exit(struct net *net)
8147 8148 8149 8150 8151
{
	kfree(net->dev_name_head);
	kfree(net->dev_index_head);
}

8152
static struct pernet_operations __net_initdata netdev_net_ops = {
8153 8154 8155 8156
	.init = netdev_init,
	.exit = netdev_exit,
};

8157
static void __net_exit default_device_exit(struct net *net)
8158
{
8159
	struct net_device *dev, *aux;
8160
	/*
8161
	 * Push all migratable network devices back to the
8162 8163 8164
	 * initial network namespace
	 */
	rtnl_lock();
8165
	for_each_netdev_safe(net, dev, aux) {
8166
		int err;
8167
		char fb_name[IFNAMSIZ];
8168 8169 8170 8171 8172

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

8173 8174 8175
		/* Leave virtual devices for the generic cleanup */
		if (dev->rtnl_link_ops)
			continue;
8176

L
Lucas De Marchi 已提交
8177
		/* Push remaining network devices to init_net */
8178 8179
		snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
		err = dev_change_net_namespace(dev, &init_net, fb_name);
8180
		if (err) {
8181 8182
			pr_emerg("%s: failed to move %s to init_net: %d\n",
				 __func__, dev->name, err);
8183
			BUG();
8184 8185 8186 8187 8188
		}
	}
	rtnl_unlock();
}

8189 8190 8191 8192 8193 8194 8195
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;
8196
	DEFINE_WAIT_FUNC(wait, woken_wake_function);
8197

8198
	add_wait_queue(&netdev_unregistering_wq, &wait);
8199 8200 8201 8202 8203 8204 8205 8206 8207 8208 8209 8210
	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();
8211 8212

		wait_woken(&wait, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
8213
	}
8214
	remove_wait_queue(&netdev_unregistering_wq, &wait);
8215 8216
}

8217 8218 8219
static void __net_exit default_device_exit_batch(struct list_head *net_list)
{
	/* At exit all network devices most be removed from a network
8220
	 * namespace.  Do this in the reverse order of registration.
8221 8222 8223 8224 8225 8226 8227
	 * 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);

8228 8229 8230 8231 8232 8233 8234 8235 8236 8237 8238 8239
	/* 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);
8240 8241
	list_for_each_entry(net, net_list, exit_list) {
		for_each_netdev_reverse(net, dev) {
8242
			if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink)
8243 8244 8245 8246 8247 8248 8249 8250 8251
				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();
}

8252
static struct pernet_operations __net_initdata default_device_ops = {
8253
	.exit = default_device_exit,
8254
	.exit_batch = default_device_exit_batch,
8255 8256
};

L
Linus Torvalds 已提交
8257 8258 8259 8260 8261 8262 8263 8264 8265 8266 8267 8268 8269 8270 8271 8272 8273 8274 8275 8276
/*
 *	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;

8277
	if (netdev_kobject_init())
L
Linus Torvalds 已提交
8278 8279 8280
		goto out;

	INIT_LIST_HEAD(&ptype_all);
8281
	for (i = 0; i < PTYPE_HASH_SIZE; i++)
L
Linus Torvalds 已提交
8282 8283
		INIT_LIST_HEAD(&ptype_base[i]);

8284 8285
	INIT_LIST_HEAD(&offload_base);

8286 8287
	if (register_pernet_subsys(&netdev_net_ops))
		goto out;
L
Linus Torvalds 已提交
8288 8289 8290 8291 8292

	/*
	 *	Initialise the packet receive queues.
	 */

8293
	for_each_possible_cpu(i) {
8294
		struct work_struct *flush = per_cpu_ptr(&flush_works, i);
E
Eric Dumazet 已提交
8295
		struct softnet_data *sd = &per_cpu(softnet_data, i);
L
Linus Torvalds 已提交
8296

8297 8298
		INIT_WORK(flush, flush_backlog);

E
Eric Dumazet 已提交
8299
		skb_queue_head_init(&sd->input_pkt_queue);
8300
		skb_queue_head_init(&sd->process_queue);
E
Eric Dumazet 已提交
8301
		INIT_LIST_HEAD(&sd->poll_list);
8302
		sd->output_queue_tailp = &sd->output_queue;
E
Eric Dumazet 已提交
8303
#ifdef CONFIG_RPS
E
Eric Dumazet 已提交
8304 8305 8306
		sd->csd.func = rps_trigger_softirq;
		sd->csd.info = sd;
		sd->cpu = i;
8307
#endif
T
Tom Herbert 已提交
8308

E
Eric Dumazet 已提交
8309 8310
		sd->backlog.poll = process_backlog;
		sd->backlog.weight = weight_p;
L
Linus Torvalds 已提交
8311 8312 8313 8314
	}

	dev_boot_phase = 0;

8315 8316 8317 8318 8319 8320 8321 8322 8323 8324 8325 8326 8327 8328 8329
	/* 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;

8330 8331
	open_softirq(NET_TX_SOFTIRQ, net_tx_action);
	open_softirq(NET_RX_SOFTIRQ, net_rx_action);
L
Linus Torvalds 已提交
8332 8333

	hotcpu_notifier(dev_cpu_callback, 0);
T
Thomas Graf 已提交
8334
	dst_subsys_init();
L
Linus Torvalds 已提交
8335 8336 8337 8338 8339 8340
	rc = 0;
out:
	return rc;
}

subsys_initcall(net_dev_init);