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/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* VLAN An implementation of 802.1Q VLAN tagging.
*
* Authors: Ben Greear <[email protected]>
*/
#ifndef _LINUX_IF_VLAN_H_
#define _LINUX_IF_VLAN_H_
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/rtnetlink.h>
#include <linux/bug.h>
#include <uapi/linux/if_vlan.h>
#define VLAN_HLEN 4 /* The additional bytes required by VLAN
* (in addition to the Ethernet header)
*/
#define VLAN_ETH_HLEN 18 /* Total octets in header. */
#define VLAN_ETH_ZLEN 64 /* Min. octets in frame sans FCS */
/*
* According to 802.3ac, the packet can be 4 bytes longer. --Klika Jan
*/
#define VLAN_ETH_DATA_LEN 1500 /* Max. octets in payload */
#define VLAN_ETH_FRAME_LEN 1518 /* Max. octets in frame sans FCS */
#define VLAN_MAX_DEPTH 8 /* Max. number of nested VLAN tags parsed */
/*
* struct vlan_hdr - vlan header
* @h_vlan_TCI: priority and VLAN ID
* @h_vlan_encapsulated_proto: packet type ID or len
*/
struct vlan_hdr {
__be16 h_vlan_TCI;
__be16 h_vlan_encapsulated_proto;
};
/**
* struct vlan_ethhdr - vlan ethernet header (ethhdr + vlan_hdr)
* @h_dest: destination ethernet address
* @h_source: source ethernet address
* @h_vlan_proto: ethernet protocol
* @h_vlan_TCI: priority and VLAN ID
* @h_vlan_encapsulated_proto: packet type ID or len
*/
struct vlan_ethhdr {
struct_group(addrs,
unsigned char h_dest[ETH_ALEN];
unsigned char h_source[ETH_ALEN];
);
__be16 h_vlan_proto;
__be16 h_vlan_TCI;
__be16 h_vlan_encapsulated_proto;
};
#include <linux/skbuff.h>
static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
{
return (struct vlan_ethhdr *)skb_mac_header(skb);
}
/* Prefer this version in TX path, instead of
* skb_reset_mac_header() + vlan_eth_hdr()
*/
static inline struct vlan_ethhdr *skb_vlan_eth_hdr(const struct sk_buff *skb)
{
return (struct vlan_ethhdr *)skb->data;
}
#define VLAN_PRIO_MASK 0xe000 /* Priority Code Point */
#define VLAN_PRIO_SHIFT 13
#define VLAN_CFI_MASK 0x1000 /* Canonical Format Indicator / Drop Eligible Indicator */
#define VLAN_VID_MASK 0x0fff /* VLAN Identifier */
#define VLAN_N_VID 4096
/* found in socket.c */
extern void vlan_ioctl_set(int (*hook)(struct net *, void __user *));
static inline bool is_vlan_dev(const struct net_device *dev)
{
return dev->priv_flags & IFF_802_1Q_VLAN;
}
#define skb_vlan_tag_present(__skb) (!!(__skb)->vlan_all)
#define skb_vlan_tag_get(__skb) ((__skb)->vlan_tci)
#define skb_vlan_tag_get_id(__skb) ((__skb)->vlan_tci & VLAN_VID_MASK)
#define skb_vlan_tag_get_cfi(__skb) (!!((__skb)->vlan_tci & VLAN_CFI_MASK))
#define skb_vlan_tag_get_prio(__skb) (((__skb)->vlan_tci & VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT)
static inline int vlan_get_rx_ctag_filter_info(struct net_device *dev)
{
ASSERT_RTNL();
return notifier_to_errno(call_netdevice_notifiers(NETDEV_CVLAN_FILTER_PUSH_INFO, dev));
}
static inline void vlan_drop_rx_ctag_filter_info(struct net_device *dev)
{
ASSERT_RTNL();
call_netdevice_notifiers(NETDEV_CVLAN_FILTER_DROP_INFO, dev);
}
static inline int vlan_get_rx_stag_filter_info(struct net_device *dev)
{
ASSERT_RTNL();
return notifier_to_errno(call_netdevice_notifiers(NETDEV_SVLAN_FILTER_PUSH_INFO, dev));
}
static inline void vlan_drop_rx_stag_filter_info(struct net_device *dev)
{
ASSERT_RTNL();
call_netdevice_notifiers(NETDEV_SVLAN_FILTER_DROP_INFO, dev);
}
/**
* struct vlan_pcpu_stats - VLAN percpu rx/tx stats
* @rx_packets: number of received packets
* @rx_bytes: number of received bytes
* @rx_multicast: number of received multicast packets
* @tx_packets: number of transmitted packets
* @tx_bytes: number of transmitted bytes
* @syncp: synchronization point for 64bit counters
* @rx_errors: number of rx errors
* @tx_dropped: number of tx drops
*/
struct vlan_pcpu_stats {
u64_stats_t rx_packets;
u64_stats_t rx_bytes;
u64_stats_t rx_multicast;
u64_stats_t tx_packets;
u64_stats_t tx_bytes;
struct u64_stats_sync syncp;
u32 rx_errors;
u32 tx_dropped;
};
#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE)
extern struct net_device *__vlan_find_dev_deep_rcu(struct net_device *real_dev,
__be16 vlan_proto, u16 vlan_id);
extern int vlan_for_each(struct net_device *dev,
int (*action)(struct net_device *dev, int vid,
void *arg), void *arg);
extern struct net_device *vlan_dev_real_dev(const struct net_device *dev);
extern u16 vlan_dev_vlan_id(const struct net_device *dev);
extern __be16 vlan_dev_vlan_proto(const struct net_device *dev);
/**
* struct vlan_priority_tci_mapping - vlan egress priority mappings
* @priority: skb priority
* @vlan_qos: vlan priority: (skb->priority << 13) & 0xE000
* @next: pointer to next struct
*/
struct vlan_priority_tci_mapping {
u32 priority;
u16 vlan_qos;
struct vlan_priority_tci_mapping *next;
};
struct proc_dir_entry;
struct netpoll;
/**
* struct vlan_dev_priv - VLAN private device data
* @nr_ingress_mappings: number of ingress priority mappings
* @ingress_priority_map: ingress priority mappings
* @nr_egress_mappings: number of egress priority mappings
* @egress_priority_map: hash of egress priority mappings
* @vlan_proto: VLAN encapsulation protocol
* @vlan_id: VLAN identifier
* @flags: device flags
* @real_dev: underlying netdevice
* @dev_tracker: refcount tracker for @real_dev reference
* @real_dev_addr: address of underlying netdevice
* @dent: proc dir entry
* @vlan_pcpu_stats: ptr to percpu rx stats
*/
struct vlan_dev_priv {
unsigned int nr_ingress_mappings;
u32 ingress_priority_map[8];
unsigned int nr_egress_mappings;
struct vlan_priority_tci_mapping *egress_priority_map[16];
__be16 vlan_proto;
u16 vlan_id;
u16 flags;
struct net_device *real_dev;
netdevice_tracker dev_tracker;
unsigned char real_dev_addr[ETH_ALEN];
struct proc_dir_entry *dent;
struct vlan_pcpu_stats __percpu *vlan_pcpu_stats;
#ifdef CONFIG_NET_POLL_CONTROLLER
struct netpoll *netpoll;
#endif
};
static inline struct vlan_dev_priv *vlan_dev_priv(const struct net_device *dev)
{
return netdev_priv(dev);
}
static inline u16
vlan_dev_get_egress_qos_mask(struct net_device *dev, u32 skprio)
{
struct vlan_priority_tci_mapping *mp;
smp_rmb(); /* coupled with smp_wmb() in vlan_dev_set_egress_priority() */
mp = vlan_dev_priv(dev)->egress_priority_map[(skprio & 0xF)];
while (mp) {
if (mp->priority == skprio) {
return mp->vlan_qos; /* This should already be shifted
* to mask correctly with the
* VLAN's TCI */
}
mp = mp->next;
}
return 0;
}
extern bool vlan_do_receive(struct sk_buff **skb);
extern int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid);
extern void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid);
extern int vlan_vids_add_by_dev(struct net_device *dev,
const struct net_device *by_dev);
extern void vlan_vids_del_by_dev(struct net_device *dev,
const struct net_device *by_dev);
extern bool vlan_uses_dev(const struct net_device *dev);
#else
static inline struct net_device *
__vlan_find_dev_deep_rcu(struct net_device *real_dev,
__be16 vlan_proto, u16 vlan_id)
{
return NULL;
}
static inline int
vlan_for_each(struct net_device *dev,
int (*action)(struct net_device *dev, int vid, void *arg),
void *arg)
{
return 0;
}
static inline struct net_device *vlan_dev_real_dev(const struct net_device *dev)
{
BUG();
return NULL;
}
static inline u16 vlan_dev_vlan_id(const struct net_device *dev)
{
BUG();
return 0;
}
static inline __be16 vlan_dev_vlan_proto(const struct net_device *dev)
{
BUG();
return 0;
}
static inline u16 vlan_dev_get_egress_qos_mask(struct net_device *dev,
u32 skprio)
{
return 0;
}
static inline bool vlan_do_receive(struct sk_buff **skb)
{
return false;
}
static inline int vlan_vid_add(struct net_device *dev, __be16 proto, u16 vid)
{
return 0;
}
static inline void vlan_vid_del(struct net_device *dev, __be16 proto, u16 vid)
{
}
static inline int vlan_vids_add_by_dev(struct net_device *dev,
const struct net_device *by_dev)
{
return 0;
}
static inline void vlan_vids_del_by_dev(struct net_device *dev,
const struct net_device *by_dev)
{
}
static inline bool vlan_uses_dev(const struct net_device *dev)
{
return false;
}
#endif
/**
* eth_type_vlan - check for valid vlan ether type.
* @ethertype: ether type to check
*
* Returns true if the ether type is a vlan ether type.
*/
static inline bool eth_type_vlan(__be16 ethertype)
{
switch (ethertype) {
case htons(ETH_P_8021Q):
case htons(ETH_P_8021AD):
return true;
default:
return false;
}
}
static inline bool vlan_hw_offload_capable(netdev_features_t features,
__be16 proto)
{
if (proto == htons(ETH_P_8021Q) && features & NETIF_F_HW_VLAN_CTAG_TX)
return true;
if (proto == htons(ETH_P_8021AD) && features & NETIF_F_HW_VLAN_STAG_TX)
return true;
return false;
}
/**
* __vlan_insert_inner_tag - inner VLAN tag inserting
* @skb: skbuff to tag
* @vlan_proto: VLAN encapsulation protocol
* @vlan_tci: VLAN TCI to insert
* @mac_len: MAC header length including outer vlan headers
*
* Inserts the VLAN tag into @skb as part of the payload at offset mac_len
* Returns error if skb_cow_head fails.
*
* Does not change skb->protocol so this function can be used during receive.
*/
static inline int __vlan_insert_inner_tag(struct sk_buff *skb,
__be16 vlan_proto, u16 vlan_tci,
unsigned int mac_len)
{
struct vlan_ethhdr *veth;
if (skb_cow_head(skb, VLAN_HLEN) < 0)
return -ENOMEM;
skb_push(skb, VLAN_HLEN);
/* Move the mac header sans proto to the beginning of the new header. */
if (likely(mac_len > ETH_TLEN))
memmove(skb->data, skb->data + VLAN_HLEN, mac_len - ETH_TLEN);
if (skb_mac_header_was_set(skb))
skb->mac_header -= VLAN_HLEN;
veth = (struct vlan_ethhdr *)(skb->data + mac_len - ETH_HLEN);
/* first, the ethernet type */
if (likely(mac_len >= ETH_TLEN)) {
/* h_vlan_encapsulated_proto should already be populated, and
* skb->data has space for h_vlan_proto
*/
veth->h_vlan_proto = vlan_proto;
} else {
/* h_vlan_encapsulated_proto should not be populated, and
* skb->data has no space for h_vlan_proto
*/
veth->h_vlan_encapsulated_proto = skb->protocol;
}
/* now, the TCI */
veth->h_vlan_TCI = htons(vlan_tci);
return 0;
}
/**
* __vlan_insert_tag - regular VLAN tag inserting
* @skb: skbuff to tag
* @vlan_proto: VLAN encapsulation protocol
* @vlan_tci: VLAN TCI to insert
*
* Inserts the VLAN tag into @skb as part of the payload
* Returns error if skb_cow_head fails.
*
* Does not change skb->protocol so this function can be used during receive.
*/
static inline int __vlan_insert_tag(struct sk_buff *skb,
__be16 vlan_proto, u16 vlan_tci)
{
return __vlan_insert_inner_tag(skb, vlan_proto, vlan_tci, ETH_HLEN);
}
/**
* vlan_insert_inner_tag - inner VLAN tag inserting
* @skb: skbuff to tag
* @vlan_proto: VLAN encapsulation protocol
* @vlan_tci: VLAN TCI to insert
* @mac_len: MAC header length including outer vlan headers
*
* Inserts the VLAN tag into @skb as part of the payload at offset mac_len
* Returns a VLAN tagged skb. This might change skb->head.
*
* Following the skb_unshare() example, in case of error, the calling function
* doesn't have to worry about freeing the original skb.
*
* Does not change skb->protocol so this function can be used during receive.
*/
static inline struct sk_buff *vlan_insert_inner_tag(struct sk_buff *skb,
__be16 vlan_proto,
u16 vlan_tci,
unsigned int mac_len)
{
int err;
err = __vlan_insert_inner_tag(skb, vlan_proto, vlan_tci, mac_len);
if (err) {
dev_kfree_skb_any(skb);
return NULL;
}
return skb;
}
/**
* vlan_insert_tag - regular VLAN tag inserting
* @skb: skbuff to tag
* @vlan_proto: VLAN encapsulation protocol
* @vlan_tci: VLAN TCI to insert
*
* Inserts the VLAN tag into @skb as part of the payload
* Returns a VLAN tagged skb. This might change skb->head.
*
* Following the skb_unshare() example, in case of error, the calling function
* doesn't have to worry about freeing the original skb.
*
* Does not change skb->protocol so this function can be used during receive.
*/
static inline struct sk_buff *vlan_insert_tag(struct sk_buff *skb,
__be16 vlan_proto, u16 vlan_tci)
{
return vlan_insert_inner_tag(skb, vlan_proto, vlan_tci, ETH_HLEN);
}
/**
* vlan_insert_tag_set_proto - regular VLAN tag inserting
* @skb: skbuff to tag
* @vlan_proto: VLAN encapsulation protocol
* @vlan_tci: VLAN TCI to insert
*
* Inserts the VLAN tag into @skb as part of the payload
* Returns a VLAN tagged skb. This might change skb->head.
*
* Following the skb_unshare() example, in case of error, the calling function
* doesn't have to worry about freeing the original skb.
*/
static inline struct sk_buff *vlan_insert_tag_set_proto(struct sk_buff *skb,
__be16 vlan_proto,
u16 vlan_tci)
{
skb = vlan_insert_tag(skb, vlan_proto, vlan_tci);
if (skb)
skb->protocol = vlan_proto;
return skb;
}
/**
* __vlan_hwaccel_clear_tag - clear hardware accelerated VLAN info
* @skb: skbuff to clear
*
* Clears the VLAN information from @skb
*/
static inline void __vlan_hwaccel_clear_tag(struct sk_buff *skb)
{
skb->vlan_all = 0;
}
/**
* __vlan_hwaccel_copy_tag - copy hardware accelerated VLAN info from another skb
* @dst: skbuff to copy to
* @src: skbuff to copy from
*
* Copies VLAN information from @src to @dst (for branchless code)
*/
static inline void __vlan_hwaccel_copy_tag(struct sk_buff *dst, const struct sk_buff *src)
{
dst->vlan_all = src->vlan_all;
}
/*
* __vlan_hwaccel_push_inside - pushes vlan tag to the payload
* @skb: skbuff to tag
*
* Pushes the VLAN tag from @skb->vlan_tci inside to the payload.
*
* Following the skb_unshare() example, in case of error, the calling function
* doesn't have to worry about freeing the original skb.
*/
static inline struct sk_buff *__vlan_hwaccel_push_inside(struct sk_buff *skb)
{
skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
skb_vlan_tag_get(skb));
if (likely(skb))
__vlan_hwaccel_clear_tag(skb);
return skb;
}
/**
* __vlan_hwaccel_put_tag - hardware accelerated VLAN inserting
* @skb: skbuff to tag
* @vlan_proto: VLAN encapsulation protocol
* @vlan_tci: VLAN TCI to insert
*
* Puts the VLAN TCI in @skb->vlan_tci and lets the device do the rest
*/
static inline void __vlan_hwaccel_put_tag(struct sk_buff *skb,
__be16 vlan_proto, u16 vlan_tci)
{
skb->vlan_proto = vlan_proto;
skb->vlan_tci = vlan_tci;
}
/**
* __vlan_get_tag - get the VLAN ID that is part of the payload
* @skb: skbuff to query
* @vlan_tci: buffer to store value
*
* Returns error if the skb is not of VLAN type
*/
static inline int __vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
{
struct vlan_ethhdr *veth = skb_vlan_eth_hdr(skb);
if (!eth_type_vlan(veth->h_vlan_proto))
return -ENODATA;
*vlan_tci = ntohs(veth->h_vlan_TCI);
return 0;
}
/**
* __vlan_hwaccel_get_tag - get the VLAN ID that is in @skb->cb[]
* @skb: skbuff to query
* @vlan_tci: buffer to store value
*
* Returns error if @skb->vlan_tci is not set correctly
*/
static inline int __vlan_hwaccel_get_tag(const struct sk_buff *skb,
u16 *vlan_tci)
{
if (skb_vlan_tag_present(skb)) {
*vlan_tci = skb_vlan_tag_get(skb);
return 0;
} else {
*vlan_tci = 0;
return -ENODATA;
}
}
/**
* vlan_get_tag - get the VLAN ID from the skb
* @skb: skbuff to query
* @vlan_tci: buffer to store value
*
* Returns error if the skb is not VLAN tagged
*/
static inline int vlan_get_tag(const struct sk_buff *skb, u16 *vlan_tci)
{
if (skb->dev->features & NETIF_F_HW_VLAN_CTAG_TX) {
return __vlan_hwaccel_get_tag(skb, vlan_tci);
} else {
return __vlan_get_tag(skb, vlan_tci);
}
}
/**
* vlan_get_protocol - get protocol EtherType.
* @skb: skbuff to query
* @type: first vlan protocol
* @mac_offset: MAC offset
* @depth: buffer to store length of eth and vlan tags in bytes
*
* Returns the EtherType of the packet, regardless of whether it is
* vlan encapsulated (normal or hardware accelerated) or not.
*/
static inline __be16 __vlan_get_protocol_offset(const struct sk_buff *skb,
__be16 type,
int mac_offset,
int *depth)
{
unsigned int vlan_depth = skb->mac_len, parse_depth = VLAN_MAX_DEPTH;
/* if type is 802.1Q/AD then the header should already be
* present at mac_len - VLAN_HLEN (if mac_len > 0), or at
* ETH_HLEN otherwise
*/
if (eth_type_vlan(type)) {
if (vlan_depth) {
if (WARN_ON(vlan_depth < VLAN_HLEN))
return 0;
vlan_depth -= VLAN_HLEN;
} else {
vlan_depth = ETH_HLEN;
}
do {
struct vlan_hdr vhdr, *vh;
vh = skb_header_pointer(skb, mac_offset + vlan_depth,
sizeof(vhdr), &vhdr);
if (unlikely(!vh || !--parse_depth))
return 0;
type = vh->h_vlan_encapsulated_proto;
vlan_depth += VLAN_HLEN;
} while (eth_type_vlan(type));
}
if (depth)
*depth = vlan_depth;
return type;
}
static inline __be16 __vlan_get_protocol(const struct sk_buff *skb, __be16 type,
int *depth)
{
return __vlan_get_protocol_offset(skb, type, 0, depth);
}
/**
* vlan_get_protocol - get protocol EtherType.
* @skb: skbuff to query
*
* Returns the EtherType of the packet, regardless of whether it is
* vlan encapsulated (normal or hardware accelerated) or not.
*/
static inline __be16 vlan_get_protocol(const struct sk_buff *skb)
{
return __vlan_get_protocol(skb, skb->protocol, NULL);
}
/* This version of __vlan_get_protocol() also pulls mac header in skb->head */
static inline __be16 vlan_get_protocol_and_depth(struct sk_buff *skb,
__be16 type, int *depth)
{
int maclen;
type = __vlan_get_protocol(skb, type, &maclen);
if (type) {
if (!pskb_may_pull(skb, maclen))
type = 0;
else if (depth)
*depth = maclen;
}
return type;
}
/* A getter for the SKB protocol field which will handle VLAN tags consistently
* whether VLAN acceleration is enabled or not.
*/
static inline __be16 skb_protocol(const struct sk_buff *skb, bool skip_vlan)
{
if (!skip_vlan)
/* VLAN acceleration strips the VLAN header from the skb and
* moves it to skb->vlan_proto
*/
return skb_vlan_tag_present(skb) ? skb->vlan_proto : skb->protocol;
return vlan_get_protocol(skb);
}
static inline void vlan_set_encap_proto(struct sk_buff *skb,
struct vlan_hdr *vhdr)
{
__be16 proto;
unsigned short *rawp;
/*
* Was a VLAN packet, grab the encapsulated protocol, which the layer
* three protocols care about.
*/
proto = vhdr->h_vlan_encapsulated_proto;
if (eth_proto_is_802_3(proto)) {
skb->protocol = proto;
return;
}
rawp = (unsigned short *)(vhdr + 1);
if (*rawp == 0xFFFF)
/*
* This is a magic hack to spot IPX packets. Older Novell
* breaks the protocol design and runs IPX over 802.3 without
* an 802.2 LLC layer. We look for FFFF which isn't a used
* 802.2 SSAP/DSAP. This won't work for fault tolerant netware
* but does for the rest.
*/
skb->protocol = htons(ETH_P_802_3);
else
/*
* Real 802.2 LLC
*/
skb->protocol = htons(ETH_P_802_2);
}
/**
* vlan_remove_tag - remove outer VLAN tag from payload
* @skb: skbuff to remove tag from
* @vlan_tci: buffer to store value
*
* Expects the skb to contain a VLAN tag in the payload, and to have skb->data
* pointing at the MAC header.
*
* Returns a new pointer to skb->data, or NULL on failure to pull.
*/
static inline void *vlan_remove_tag(struct sk_buff *skb, u16 *vlan_tci)
{
struct vlan_hdr *vhdr = (struct vlan_hdr *)(skb->data + ETH_HLEN);
*vlan_tci = ntohs(vhdr->h_vlan_TCI);
memmove(skb->data + VLAN_HLEN, skb->data, 2 * ETH_ALEN);
vlan_set_encap_proto(skb, vhdr);
return __skb_pull(skb, VLAN_HLEN);
}
/**
* skb_vlan_tagged - check if skb is vlan tagged.
* @skb: skbuff to query
*
* Returns true if the skb is tagged, regardless of whether it is hardware
* accelerated or not.
*/
static inline bool skb_vlan_tagged(const struct sk_buff *skb)
{
if (!skb_vlan_tag_present(skb) &&
likely(!eth_type_vlan(skb->protocol)))
return false;
return true;
}
/**
* skb_vlan_tagged_multi - check if skb is vlan tagged with multiple headers.
* @skb: skbuff to query
*
* Returns true if the skb is tagged with multiple vlan headers, regardless
* of whether it is hardware accelerated or not.
*/
static inline bool skb_vlan_tagged_multi(struct sk_buff *skb)
{
__be16 protocol = skb->protocol;
if (!skb_vlan_tag_present(skb)) {
struct vlan_ethhdr *veh;
if (likely(!eth_type_vlan(protocol)))
return false;
if (unlikely(!pskb_may_pull(skb, VLAN_ETH_HLEN)))
return false;
veh = skb_vlan_eth_hdr(skb);
protocol = veh->h_vlan_encapsulated_proto;
}
if (!eth_type_vlan(protocol))
return false;
return true;
}
/**
* vlan_features_check - drop unsafe features for skb with multiple tags.
* @skb: skbuff to query
* @features: features to be checked
*
* Returns features without unsafe ones if the skb has multiple tags.
*/
static inline netdev_features_t vlan_features_check(struct sk_buff *skb,
netdev_features_t features)
{
if (skb_vlan_tagged_multi(skb)) {
/* In the case of multi-tagged packets, use a direct mask
* instead of using netdev_interesect_features(), to make
* sure that only devices supporting NETIF_F_HW_CSUM will
* have checksum offloading support.
*/
features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_HW_CSUM |
NETIF_F_FRAGLIST | NETIF_F_HW_VLAN_CTAG_TX |
NETIF_F_HW_VLAN_STAG_TX;
}
return features;
}
/**
* compare_vlan_header - Compare two vlan headers
* @h1: Pointer to vlan header
* @h2: Pointer to vlan header
*
* Compare two vlan headers, returns 0 if equal.
*
* Please note that alignment of h1 & h2 are only guaranteed to be 16 bits.
*/
static inline unsigned long compare_vlan_header(const struct vlan_hdr *h1,
const struct vlan_hdr *h2)
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
return *(u32 *)h1 ^ *(u32 *)h2;
#else
return ((__force u32)h1->h_vlan_TCI ^ (__force u32)h2->h_vlan_TCI) |
((__force u32)h1->h_vlan_encapsulated_proto ^
(__force u32)h2->h_vlan_encapsulated_proto);
#endif
}
#endif /* !(_LINUX_IF_VLAN_H_) */
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