[SK_BUFF]: Convert skb->tail to sk_buff_data_t
So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes
on 64bit architectures, allowing us to combine the 4 bytes hole left by the
layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4
64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN...
:-)
Many calculations that previously required that skb->{transport,network,
mac}_header be first converted to a pointer now can be done directly, being
meaningful as offsets or pointers.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index f16f4f0..4a355fe 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -268,7 +268,7 @@
serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
serr->port = fl->fl_ip_dport;
- __skb_pull(skb, skb->tail - skb->data);
+ __skb_pull(skb, skb_tail_pointer(skb) - skb->data);
skb_reset_transport_header(skb);
if (sock_queue_err_skb(sk, skb))
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 7fdf84d..b8e8914 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -51,6 +51,7 @@
int clen;
int alen;
int nfrags;
+ u8 *tail;
struct esp_data *esp = x->data;
int hdr_len = (skb_transport_offset(skb) +
sizeof(*esph) + esp->conf.ivlen);
@@ -78,18 +79,19 @@
}
/* Fill padding... */
+ tail = skb_tail_pointer(trailer);
do {
int i;
for (i=0; i<clen-skb->len - 2; i++)
- *(u8*)(trailer->tail + i) = i+1;
+ tail[i] = i + 1;
} while (0);
- *(u8*)(trailer->tail + clen-skb->len - 2) = (clen - skb->len)-2;
+ tail[clen-skb->len - 2] = (clen - skb->len) - 2;
pskb_put(skb, trailer, clen - skb->len);
top_iph = (struct ipv6hdr *)__skb_push(skb, hdr_len);
esph = (struct ipv6_esp_hdr *)skb_transport_header(skb);
top_iph->payload_len = htons(skb->len + alen - sizeof(*top_iph));
- *(u8 *)(trailer->tail - 1) = *skb_network_header(skb);
+ *(skb_tail_pointer(skb) - 1) = *skb_network_header(skb);
*skb_network_header(skb) = IPPROTO_ESP;
esph->spi = x->id.spi;
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index a6a275d..275d2e8 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -51,7 +51,7 @@
int ipv6_find_tlv(struct sk_buff *skb, int offset, int type)
{
const unsigned char *nh = skb_network_header(skb);
- int packet_len = skb->tail - nh;
+ int packet_len = skb->tail - skb->network_header;
struct ipv6_opt_hdr *hdr;
int len;
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index d3edc3c..e94992a 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -317,7 +317,8 @@
int hlimit, tclass;
int err = 0;
- if ((u8*)hdr < skb->head || (u8*)(hdr+1) > skb->tail)
+ if ((u8 *)hdr < skb->head ||
+ (skb->network_header + sizeof(*hdr)) > skb->tail)
return;
/*
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index b2c092c..e2b8db6 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -514,7 +514,7 @@
u16 offset = sizeof(struct ipv6hdr);
struct ipv6_opt_hdr *exthdr =
(struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
- unsigned int packet_len = skb->tail - skb_network_header(skb);
+ unsigned int packet_len = skb->tail - skb->network_header;
int found_rhdr = 0;
*nexthdr = &ipv6_hdr(skb)->nexthdr;
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 4c45bcc..6c27589 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -1423,7 +1423,7 @@
memcpy(skb_put(skb, sizeof(ra)), ra, sizeof(ra));
- skb_set_transport_header(skb, skb->tail - skb->data);
+ skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);
skb_put(skb, sizeof(*pmr));
pmr = (struct mld2_report *)skb_transport_header(skb);
pmr->type = ICMPV6_MLD2_REPORT;
@@ -1468,8 +1468,8 @@
int err;
IP6_INC_STATS(idev, IPSTATS_MIB_OUTREQUESTS);
- payload_len = skb->tail - skb_network_header(skb) - sizeof(*pip6);
- mldlen = skb->tail - skb_transport_header(skb);
+ payload_len = (skb->tail - skb->network_header) - sizeof(*pip6);
+ mldlen = skb->tail - skb->transport_header;
pip6->payload_len = htons(payload_len);
pmr->csum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
diff --git a/net/ipv6/mip6.c b/net/ipv6/mip6.c
index f0288e9..6ed763e 100644
--- a/net/ipv6/mip6.c
+++ b/net/ipv6/mip6.c
@@ -260,7 +260,7 @@
struct ipv6_opt_hdr *exthdr =
(struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
const unsigned char *nh = skb_network_header(skb);
- unsigned int packet_len = skb->tail - nh;
+ unsigned int packet_len = skb->tail - skb->network_header;
int found_rhdr = 0;
*nexthdr = &ipv6_hdr(skb)->nexthdr;
@@ -392,7 +392,7 @@
struct ipv6_opt_hdr *exthdr =
(struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
const unsigned char *nh = skb_network_header(skb);
- unsigned int packet_len = skb->tail - nh;
+ unsigned int packet_len = skb->tail - skb->network_header;
int found_rhdr = 0;
*nexthdr = &ipv6_hdr(skb)->nexthdr;
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index f8e6197..b1cf708 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -492,7 +492,7 @@
skb_reserve(skb, LL_RESERVED_SPACE(dev));
ip6_nd_hdr(sk, skb, dev, src_addr, daddr, IPPROTO_ICMPV6, len);
- skb_set_transport_header(skb, skb->tail - skb->data);
+ skb->transport_header = skb->tail;
skb_put(skb, len);
msg = (struct nd_msg *)skb_transport_header(skb);
@@ -584,7 +584,7 @@
skb_reserve(skb, LL_RESERVED_SPACE(dev));
ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
- skb_set_transport_header(skb, skb->tail - skb->data);
+ skb->transport_header = skb->tail;
skb_put(skb, len);
msg = (struct nd_msg *)skb_transport_header(skb);
msg->icmph.icmp6_type = NDISC_NEIGHBOUR_SOLICITATION;
@@ -685,7 +685,7 @@
skb_reserve(skb, LL_RESERVED_SPACE(dev));
ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
- skb_set_transport_header(skb, skb->tail - skb->data);
+ skb->transport_header = skb->tail;
skb_put(skb, len);
hdr = icmp6_hdr(skb);
hdr->icmp6_type = NDISC_ROUTER_SOLICITATION;
@@ -767,7 +767,8 @@
struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
u8 *lladdr = NULL;
- u32 ndoptlen = skb->tail - msg->opt;
+ u32 ndoptlen = skb->tail - (skb->transport_header +
+ offsetof(struct nd_msg, opt));
struct ndisc_options ndopts;
struct net_device *dev = skb->dev;
struct inet6_ifaddr *ifp;
@@ -945,7 +946,8 @@
struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
u8 *lladdr = NULL;
- u32 ndoptlen = skb->tail - msg->opt;
+ u32 ndoptlen = skb->tail - (skb->transport_header +
+ offsetof(struct nd_msg, opt));
struct ndisc_options ndopts;
struct net_device *dev = skb->dev;
struct inet6_ifaddr *ifp;
@@ -1111,8 +1113,7 @@
__u8 * opt = (__u8 *)(ra_msg + 1);
- optlen = (skb->tail - skb_transport_header(skb)) -
- sizeof(struct ra_msg);
+ optlen = (skb->tail - skb->transport_header) - sizeof(struct ra_msg);
if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
ND_PRINTK2(KERN_WARNING
@@ -1361,7 +1362,7 @@
return;
}
- optlen = skb->tail - skb_transport_header(skb);
+ optlen = skb->tail - skb->transport_header;
optlen -= sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
if (optlen < 0) {
@@ -1522,7 +1523,7 @@
ip6_nd_hdr(sk, buff, dev, &saddr_buf, &ipv6_hdr(skb)->saddr,
IPPROTO_ICMPV6, len);
- skb_set_transport_header(buff, buff->tail - buff->data);
+ skb_set_transport_header(buff, skb_tail_pointer(buff) - buff->data);
skb_put(buff, len);
icmph = icmp6_hdr(buff);
diff --git a/net/ipv6/netfilter/ip6_queue.c b/net/ipv6/netfilter/ip6_queue.c
index 66a2c41..5cfce21 100644
--- a/net/ipv6/netfilter/ip6_queue.c
+++ b/net/ipv6/netfilter/ip6_queue.c
@@ -189,7 +189,7 @@
static struct sk_buff *
ipq_build_packet_message(struct ipq_queue_entry *entry, int *errp)
{
- unsigned char *old_tail;
+ sk_buff_data_t old_tail;
size_t size = 0;
size_t data_len = 0;
struct sk_buff *skb;
@@ -233,7 +233,7 @@
if (!skb)
goto nlmsg_failure;
- old_tail= skb->tail;
+ old_tail = skb->tail;
nlh = NLMSG_PUT(skb, 0, 0, IPQM_PACKET, size - sizeof(*nlh));
pmsg = NLMSG_DATA(nlh);
memset(pmsg, 0, sizeof(*pmsg));
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index 8705f6a..2b3be68 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -1077,7 +1077,7 @@
spin_lock_bh(&sk->sk_receive_queue.lock);
skb = skb_peek(&sk->sk_receive_queue);
if (skb != NULL)
- amount = skb->tail - skb_transport_header(skb);
+ amount = skb->tail - skb->transport_header;
spin_unlock_bh(&sk->sk_receive_queue.lock);
return put_user(amount, (int __user *)arg);
}