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net: vlan: make non-hw-accel rx path similar to hw-accel
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Now there are 2 paths for rx vlan frames. When rx-vlan-hw-accel is
enabled, skb is untagged by NIC, vlan_tci is set and the skb gets into
vlan code in __netif_receive_skb - vlan_hwaccel_do_receive.

For non-rx-vlan-hw-accel however, tagged skb goes thru whole
__netif_receive_skb, it's untagged in ptype_base hander and reinjected

This incosistency is fixed by this patch. Vlan untagging happens early in
__netif_receive_skb so the rest of code (ptype_all handlers, rx_handlers)
see the skb like it was untagged by hw.

Signed-off-by: Jiri Pirko <jpirko@redhat.com>

v1->v2:
	remove "inline" from vlan_core.c functions
Signed-off-by: David S. Miller <davem@davemloft.net>
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@davem330
Jiri Pirko authored and davem330 committed Apr 12, 2011
1 parent 143780c commit bcc6d47
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Showing 6 changed files with 99 additions and 187 deletions.
10 changes: 8 additions & 2 deletions include/linux/if_vlan.h
View file
Expand Up @@ -132,7 +132,8 @@ extern u16 vlan_dev_vlan_id(const struct net_device *dev);

extern int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
u16 vlan_tci, int polling);
extern bool vlan_hwaccel_do_receive(struct sk_buff **skb);
extern bool vlan_do_receive(struct sk_buff **skb);
extern struct sk_buff *vlan_untag(struct sk_buff *skb);
extern gro_result_t
vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
unsigned int vlan_tci, struct sk_buff *skb);
Expand Down Expand Up @@ -166,13 +167,18 @@ static inline int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
return NET_XMIT_SUCCESS;
}

static inline bool vlan_hwaccel_do_receive(struct sk_buff **skb)
static inline bool vlan_do_receive(struct sk_buff **skb)
{
if ((*skb)->vlan_tci & VLAN_VID_MASK)
(*skb)->pkt_type = PACKET_OTHERHOST;
return false;
}

inline struct sk_buff *vlan_untag(struct sk_buff *skb)
{
return skb;
}

static inline gro_result_t
vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
unsigned int vlan_tci, struct sk_buff *skb)
Expand Down
8 changes: 0 additions & 8 deletions net/8021q/vlan.c
View file
Expand Up @@ -49,11 +49,6 @@ const char vlan_version[] = DRV_VERSION;
static const char vlan_copyright[] = "Ben Greear <greearb@candelatech.com>";
static const char vlan_buggyright[] = "David S. Miller <davem@redhat.com>";

static struct packet_type vlan_packet_type __read_mostly = {
.type = cpu_to_be16(ETH_P_8021Q),
.func = vlan_skb_recv, /* VLAN receive method */
};

/* End of global variables definitions. */

static void vlan_group_free(struct vlan_group *grp)
Expand Down Expand Up @@ -684,7 +679,6 @@ static int __init vlan_proto_init(void)
if (err < 0)
goto err4;

dev_add_pack(&vlan_packet_type);
vlan_ioctl_set(vlan_ioctl_handler);
return 0;

Expand All @@ -705,8 +699,6 @@ static void __exit vlan_cleanup_module(void)

unregister_netdevice_notifier(&vlan_notifier_block);

dev_remove_pack(&vlan_packet_type);

unregister_pernet_subsys(&vlan_net_ops);
rcu_barrier(); /* Wait for completion of call_rcu()'s */

Expand Down
2 changes: 0 additions & 2 deletions net/8021q/vlan.h
View file
Expand Up @@ -75,8 +75,6 @@ static inline struct vlan_dev_info *vlan_dev_info(const struct net_device *dev)
}

/* found in vlan_dev.c */
int vlan_skb_recv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *ptype, struct net_device *orig_dev);
void vlan_dev_set_ingress_priority(const struct net_device *dev,
u32 skb_prio, u16 vlan_prio);
int vlan_dev_set_egress_priority(const struct net_device *dev,
Expand Down
85 changes: 84 additions & 1 deletion net/8021q/vlan_core.c
View file
Expand Up @@ -4,7 +4,7 @@
#include <linux/netpoll.h>
#include "vlan.h"

bool vlan_hwaccel_do_receive(struct sk_buff **skbp)
bool vlan_do_receive(struct sk_buff **skbp)
{
struct sk_buff *skb = *skbp;
u16 vlan_id = skb->vlan_tci & VLAN_VID_MASK;
Expand Down Expand Up @@ -88,3 +88,86 @@ gro_result_t vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
return napi_gro_frags(napi);
}
EXPORT_SYMBOL(vlan_gro_frags);

static struct sk_buff *vlan_check_reorder_header(struct sk_buff *skb)
{
if (vlan_dev_info(skb->dev)->flags & VLAN_FLAG_REORDER_HDR) {
if (skb_cow(skb, skb_headroom(skb)) < 0)
skb = NULL;
if (skb) {
/* Lifted from Gleb's VLAN code... */
memmove(skb->data - ETH_HLEN,
skb->data - VLAN_ETH_HLEN, 12);
skb->mac_header += VLAN_HLEN;
}
}
return skb;
}

static void vlan_set_encap_proto(struct sk_buff *skb, struct vlan_hdr *vhdr)
{
__be16 proto;
unsigned char *rawp;

/*
* Was a VLAN packet, grab the encapsulated protocol, which the layer
* three protocols care about.
*/

proto = vhdr->h_vlan_encapsulated_proto;
if (ntohs(proto) >= 1536) {
skb->protocol = proto;
return;
}

rawp = skb->data;
if (*(unsigned short *) 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);
}

struct sk_buff *vlan_untag(struct sk_buff *skb)
{
struct vlan_hdr *vhdr;
u16 vlan_tci;

if (unlikely(vlan_tx_tag_present(skb))) {
/* vlan_tci is already set-up so leave this for another time */
return skb;
}

skb = skb_share_check(skb, GFP_ATOMIC);
if (unlikely(!skb))
goto err_free;

if (unlikely(!pskb_may_pull(skb, VLAN_HLEN)))
goto err_free;

vhdr = (struct vlan_hdr *) skb->data;
vlan_tci = ntohs(vhdr->h_vlan_TCI);
__vlan_hwaccel_put_tag(skb, vlan_tci);

skb_pull_rcsum(skb, VLAN_HLEN);
vlan_set_encap_proto(skb, vhdr);

skb = vlan_check_reorder_header(skb);
if (unlikely(!skb))
goto err_free;

return skb;

err_free:
kfree_skb(skb);
return NULL;
}
173 changes: 0 additions & 173 deletions net/8021q/vlan_dev.c
View file
Expand Up @@ -65,179 +65,6 @@ static int vlan_dev_rebuild_header(struct sk_buff *skb)
return 0;
}

static inline struct sk_buff *vlan_check_reorder_header(struct sk_buff *skb)
{
if (vlan_dev_info(skb->dev)->flags & VLAN_FLAG_REORDER_HDR) {
if (skb_cow(skb, skb_headroom(skb)) < 0)
skb = NULL;
if (skb) {
/* Lifted from Gleb's VLAN code... */
memmove(skb->data - ETH_HLEN,
skb->data - VLAN_ETH_HLEN, 12);
skb->mac_header += VLAN_HLEN;
}
}

return skb;
}

static inline void vlan_set_encap_proto(struct sk_buff *skb,
struct vlan_hdr *vhdr)
{
__be16 proto;
unsigned char *rawp;

/*
* Was a VLAN packet, grab the encapsulated protocol, which the layer
* three protocols care about.
*/

proto = vhdr->h_vlan_encapsulated_proto;
if (ntohs(proto) >= 1536) {
skb->protocol = proto;
return;
}

rawp = skb->data;
if (*(unsigned short *)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);
}

/*
* Determine the packet's protocol ID. The rule here is that we
* assume 802.3 if the type field is short enough to be a length.
* This is normal practice and works for any 'now in use' protocol.
*
* Also, at this point we assume that we ARE dealing exclusively with
* VLAN packets, or packets that should be made into VLAN packets based
* on a default VLAN ID.
*
* NOTE: Should be similar to ethernet/eth.c.
*
* SANITY NOTE: This method is called when a packet is moving up the stack
* towards userland. To get here, it would have already passed
* through the ethernet/eth.c eth_type_trans() method.
* SANITY NOTE 2: We are referencing to the VLAN_HDR frields, which MAY be
* stored UNALIGNED in the memory. RISC systems don't like
* such cases very much...
* SANITY NOTE 2a: According to Dave Miller & Alexey, it will always be
* aligned, so there doesn't need to be any of the unaligned
* stuff. It has been commented out now... --Ben
*
*/
int vlan_skb_recv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *ptype, struct net_device *orig_dev)
{
struct vlan_hdr *vhdr;
struct vlan_pcpu_stats *rx_stats;
struct net_device *vlan_dev;
u16 vlan_id;
u16 vlan_tci;

skb = skb_share_check(skb, GFP_ATOMIC);
if (skb == NULL)
goto err_free;

if (unlikely(!pskb_may_pull(skb, VLAN_HLEN)))
goto err_free;

vhdr = (struct vlan_hdr *)skb->data;
vlan_tci = ntohs(vhdr->h_vlan_TCI);
vlan_id = vlan_tci & VLAN_VID_MASK;

rcu_read_lock();
vlan_dev = vlan_find_dev(dev, vlan_id);

/* If the VLAN device is defined, we use it.
* If not, and the VID is 0, it is a 802.1p packet (not
* really a VLAN), so we will just netif_rx it later to the
* original interface, but with the skb->proto set to the
* wrapped proto: we do nothing here.
*/

if (!vlan_dev) {
if (vlan_id) {
pr_debug("%s: ERROR: No net_device for VID: %u on dev: %s\n",
__func__, vlan_id, dev->name);
goto err_unlock;
}
rx_stats = NULL;
} else {
skb->dev = vlan_dev;

rx_stats = this_cpu_ptr(vlan_dev_info(skb->dev)->vlan_pcpu_stats);

u64_stats_update_begin(&rx_stats->syncp);
rx_stats->rx_packets++;
rx_stats->rx_bytes += skb->len;

skb->priority = vlan_get_ingress_priority(skb->dev, vlan_tci);

pr_debug("%s: priority: %u for TCI: %hu\n",
__func__, skb->priority, vlan_tci);

switch (skb->pkt_type) {
case PACKET_BROADCAST:
/* Yeah, stats collect these together.. */
/* stats->broadcast ++; // no such counter :-( */
break;

case PACKET_MULTICAST:
rx_stats->rx_multicast++;
break;

case PACKET_OTHERHOST:
/* Our lower layer thinks this is not local, let's make
* sure.
* This allows the VLAN to have a different MAC than the
* underlying device, and still route correctly.
*/
if (!compare_ether_addr(eth_hdr(skb)->h_dest,
skb->dev->dev_addr))
skb->pkt_type = PACKET_HOST;
break;
default:
break;
}
u64_stats_update_end(&rx_stats->syncp);
}

skb_pull_rcsum(skb, VLAN_HLEN);
vlan_set_encap_proto(skb, vhdr);

if (vlan_dev) {
skb = vlan_check_reorder_header(skb);
if (!skb) {
rx_stats->rx_errors++;
goto err_unlock;
}
}

netif_rx(skb);

rcu_read_unlock();
return NET_RX_SUCCESS;

err_unlock:
rcu_read_unlock();
err_free:
atomic_long_inc(&dev->rx_dropped);
kfree_skb(skb);
return NET_RX_DROP;
}

static inline u16
vlan_dev_get_egress_qos_mask(struct net_device *dev, struct sk_buff *skb)
{
Expand Down
8 changes: 7 additions & 1 deletion net/core/dev.c
View file
Expand Up @@ -3130,6 +3130,12 @@ static int __netif_receive_skb(struct sk_buff *skb)

__this_cpu_inc(softnet_data.processed);

if (skb->protocol == cpu_to_be16(ETH_P_8021Q)) {
skb = vlan_untag(skb);
if (unlikely(!skb))
goto out;
}

#ifdef CONFIG_NET_CLS_ACT
if (skb->tc_verd & TC_NCLS) {
skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
Expand Down Expand Up @@ -3177,7 +3183,7 @@ static int __netif_receive_skb(struct sk_buff *skb)
ret = deliver_skb(skb, pt_prev, orig_dev);
pt_prev = NULL;
}
if (vlan_hwaccel_do_receive(&skb)) {
if (vlan_do_receive(&skb)) {
ret = __netif_receive_skb(skb);
goto out;
} else if (unlikely(!skb))
Expand Down

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