[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>

25 files changed, 98 insertions, 95 deletions

diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index cb21617..28326fb 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -93,7 +93,7 @@ static int tcf_dump_walker(struct sk_buff *skb, struct netlink_callback *cb,
 				continue;
 			a->priv = p;
 			a->order = n_i;
-			r = (struct rtattr*) skb->tail;
+			r = (struct rtattr *)skb_tail_pointer(skb);
 			RTA_PUT(skb, a->order, 0, NULL);
 			err = tcf_action_dump_1(skb, a, 0, 0);
 			if (err < 0) {
@@ -101,7 +101,7 @@ static int tcf_dump_walker(struct sk_buff *skb, struct netlink_callback *cb,
 				skb_trim(skb, (u8*)r - skb->data);
 				goto done;
 			}
-			r->rta_len = skb->tail - (u8*)r;
+			r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
 			n_i++;
 			if (n_i >= TCA_ACT_MAX_PRIO)
 				goto done;
@@ -125,7 +125,7 @@ static int tcf_del_walker(struct sk_buff *skb, struct tc_action *a,
 	struct rtattr *r ;
 	int i= 0, n_i = 0;
 
-	r = (struct rtattr*) skb->tail;
+	r = (struct rtattr *)skb_tail_pointer(skb);
 	RTA_PUT(skb, a->order, 0, NULL);
 	RTA_PUT(skb, TCA_KIND, IFNAMSIZ, a->ops->kind);
 	for (i = 0; i < (hinfo->hmask + 1); i++) {
@@ -140,7 +140,7 @@ static int tcf_del_walker(struct sk_buff *skb, struct tc_action *a,
 		}
 	}
 	RTA_PUT(skb, TCA_FCNT, 4, &n_i);
-	r->rta_len = skb->tail - (u8*)r;
+	r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
 
 	return n_i;
 rtattr_failure:
@@ -423,7 +423,7 @@ int
 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 {
 	int err = -EINVAL;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *r;
 
 	if (a->ops == NULL || a->ops->dump == NULL)
@@ -432,10 +432,10 @@ tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 	RTA_PUT(skb, TCA_KIND, IFNAMSIZ, a->ops->kind);
 	if (tcf_action_copy_stats(skb, a, 0))
 		goto rtattr_failure;
-	r = (struct rtattr*) skb->tail;
+	r = (struct rtattr *)skb_tail_pointer(skb);
 	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 	if ((err = tcf_action_dump_old(skb, a, bind, ref)) > 0) {
-		r->rta_len = skb->tail - (u8*)r;
+		r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
 		return err;
 	}
 
@@ -449,17 +449,17 @@ tcf_action_dump(struct sk_buff *skb, struct tc_action *act, int bind, int ref)
 {
 	struct tc_action *a;
 	int err = -EINVAL;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *r ;
 
 	while ((a = act) != NULL) {
-		r = (struct rtattr*) skb->tail;
+		r = (struct rtattr *)skb_tail_pointer(skb);
 		act = a->next;
 		RTA_PUT(skb, a->order, 0, NULL);
 		err = tcf_action_dump_1(skb, a, bind, ref);
 		if (err < 0)
 			goto errout;
-		r->rta_len = skb->tail - (u8*)r;
+		r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
 	}
 
 	return 0;
@@ -635,7 +635,7 @@ tca_get_fill(struct sk_buff *skb, struct tc_action *a, u32 pid, u32 seq,
 {
 	struct tcamsg *t;
 	struct nlmsghdr *nlh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *x;
 
 	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
@@ -645,15 +645,15 @@ tca_get_fill(struct sk_buff *skb, struct tc_action *a, u32 pid, u32 seq,
 	t->tca__pad1 = 0;
 	t->tca__pad2 = 0;
 
-	x = (struct rtattr*) skb->tail;
+	x = (struct rtattr *)skb_tail_pointer(skb);
 	RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
 
 	if (tcf_action_dump(skb, a, bind, ref) < 0)
 		goto rtattr_failure;
 
-	x->rta_len = skb->tail - (u8*)x;
+	x->rta_len = skb_tail_pointer(skb) - (u8 *)x;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 rtattr_failure:
@@ -767,7 +767,7 @@ static int tca_action_flush(struct rtattr *rta, struct nlmsghdr *n, u32 pid)
 		return -ENOBUFS;
 	}
 
-	b = (unsigned char *)skb->tail;
+	b = skb_tail_pointer(skb);
 
 	if (rtattr_parse_nested(tb, TCA_ACT_MAX, rta) < 0)
 		goto err_out;
@@ -783,16 +783,16 @@ static int tca_action_flush(struct rtattr *rta, struct nlmsghdr *n, u32 pid)
 	t->tca__pad1 = 0;
 	t->tca__pad2 = 0;
 
-	x = (struct rtattr *) skb->tail;
+	x = (struct rtattr *)skb_tail_pointer(skb);
 	RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
 
 	err = a->ops->walk(skb, &dcb, RTM_DELACTION, a);
 	if (err < 0)
 		goto rtattr_failure;
 
-	x->rta_len = skb->tail - (u8 *) x;
+	x->rta_len = skb_tail_pointer(skb) - (u8 *)x;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	nlh->nlmsg_flags |= NLM_F_ROOT;
 	module_put(a->ops->owner);
 	kfree(a);
@@ -884,7 +884,7 @@ static int tcf_add_notify(struct tc_action *a, u32 pid, u32 seq, int event,
 	if (!skb)
 		return -ENOBUFS;
 
-	b = (unsigned char *)skb->tail;
+	b = skb_tail_pointer(skb);
 
 	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
 	t = NLMSG_DATA(nlh);
@@ -892,15 +892,15 @@ static int tcf_add_notify(struct tc_action *a, u32 pid, u32 seq, int event,
 	t->tca__pad1 = 0;
 	t->tca__pad2 = 0;
 
-	x = (struct rtattr*) skb->tail;
+	x = (struct rtattr *)skb_tail_pointer(skb);
 	RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
 
 	if (tcf_action_dump(skb, a, 0, 0) < 0)
 		goto rtattr_failure;
 
-	x->rta_len = skb->tail - (u8*)x;
+	x->rta_len = skb_tail_pointer(skb) - (u8 *)x;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	NETLINK_CB(skb).dst_group = RTNLGRP_TC;
 
 	err = rtnetlink_send(skb, pid, RTNLGRP_TC, flags&NLM_F_ECHO);
@@ -1015,7 +1015,7 @@ static int
 tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
 {
 	struct nlmsghdr *nlh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *x;
 	struct tc_action_ops *a_o;
 	struct tc_action a;
@@ -1048,7 +1048,7 @@ tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
 	t->tca__pad1 = 0;
 	t->tca__pad2 = 0;
 
-	x = (struct rtattr *) skb->tail;
+	x = (struct rtattr *)skb_tail_pointer(skb);
 	RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
 
 	ret = a_o->walk(skb, cb, RTM_GETACTION, &a);
@@ -1056,12 +1056,12 @@ tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
 		goto rtattr_failure;
 
 	if (ret > 0) {
-		x->rta_len = skb->tail - (u8 *) x;
+		x->rta_len = skb_tail_pointer(skb) - (u8 *)x;
 		ret = skb->len;
 	} else
 		skb_trim(skb, (u8*)x - skb->data);
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	if (NETLINK_CB(cb->skb).pid && ret)
 		nlh->nlmsg_flags |= NLM_F_MULTI;
 	module_put(a_o->owner);
diff --git a/net/sched/act_gact.c b/net/sched/act_gact.c
index 87d0faf..aad748b3 100644
--- a/net/sched/act_gact.c
+++ b/net/sched/act_gact.c
@@ -155,7 +155,7 @@ static int tcf_gact(struct sk_buff *skb, struct tc_action *a, struct tcf_result
 
 static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 {
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_gact opt;
 	struct tcf_gact *gact = a->priv;
 	struct tcf_t t;
diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c
index 47f0b13..2ccfd5b 100644
--- a/net/sched/act_ipt.c
+++ b/net/sched/act_ipt.c
@@ -245,7 +245,7 @@ static int tcf_ipt(struct sk_buff *skb, struct tc_action *a,
 
 static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 {
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tcf_ipt *ipt = a->priv;
 	struct ipt_entry_target *t;
 	struct tcf_t tm;
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index 3e93683..15f6ecd 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -206,7 +206,7 @@ bad_mirred:
 
 static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 {
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tcf_mirred *m = a->priv;
 	struct tc_mirred opt;
 	struct tcf_t t;
diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c
index 20813ee..d654cea 100644
--- a/net/sched/act_pedit.c
+++ b/net/sched/act_pedit.c
@@ -195,7 +195,7 @@ done:
 static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
 			  int bind, int ref)
 {
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tcf_pedit *p = a->priv;
 	struct tc_pedit *opt;
 	struct tcf_t t;
diff --git a/net/sched/act_police.c b/net/sched/act_police.c
index 10a5a5c..068b237 100644
--- a/net/sched/act_police.c
+++ b/net/sched/act_police.c
@@ -80,7 +80,7 @@ static int tcf_act_police_walker(struct sk_buff *skb, struct netlink_callback *c
 				continue;
 			a->priv = p;
 			a->order = index;
-			r = (struct rtattr*) skb->tail;
+			r = (struct rtattr *)skb_tail_pointer(skb);
 			RTA_PUT(skb, a->order, 0, NULL);
 			if (type == RTM_DELACTION)
 				err = tcf_action_dump_1(skb, a, 0, 1);
@@ -91,7 +91,7 @@ static int tcf_act_police_walker(struct sk_buff *skb, struct netlink_callback *c
 				skb_trim(skb, (u8*)r - skb->data);
 				goto done;
 			}
-			r->rta_len = skb->tail - (u8*)r;
+			r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
 			n_i++;
 		}
 	}
@@ -326,7 +326,7 @@ static int tcf_act_police(struct sk_buff *skb, struct tc_action *a,
 static int
 tcf_act_police_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 {
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tcf_police *police = a->priv;
 	struct tc_police opt;
 
@@ -572,7 +572,7 @@ EXPORT_SYMBOL(tcf_police);
 
 int tcf_police_dump(struct sk_buff *skb, struct tcf_police *police)
 {
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_police opt;
 
 	opt.index = police->tcf_index;
diff --git a/net/sched/act_simple.c b/net/sched/act_simple.c
index c797118..ecbcfa5 100644
--- a/net/sched/act_simple.c
+++ b/net/sched/act_simple.c
@@ -155,7 +155,7 @@ static inline int tcf_simp_cleanup(struct tc_action *a, int bind)
 static inline int tcf_simp_dump(struct sk_buff *skb, struct tc_action *a,
 				int bind, int ref)
 {
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tcf_defact *d = a->priv;
 	struct tc_defact opt;
 	struct tcf_t t;
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 5c6ffdb..84231ba 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -323,7 +323,7 @@ tcf_fill_node(struct sk_buff *skb, struct tcf_proto *tp, unsigned long fh,
 {
 	struct tcmsg *tcm;
 	struct nlmsghdr  *nlh;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 
 	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags);
 	tcm = NLMSG_DATA(nlh);
@@ -340,7 +340,7 @@ tcf_fill_node(struct sk_buff *skb, struct tcf_proto *tp, unsigned long fh,
 		if (tp->ops->dump && tp->ops->dump(tp, fh, skb, tcm) < 0)
 			goto rtattr_failure;
 	}
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 nlmsg_failure:
@@ -563,30 +563,30 @@ tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts,
 		 * to work with both old and new modes of entering
 		 * tc data even if iproute2  was newer - jhs
 		 */
-		struct rtattr * p_rta = (struct rtattr*) skb->tail;
+		struct rtattr *p_rta = (struct rtattr *)skb_tail_pointer(skb);
 
 		if (exts->action->type != TCA_OLD_COMPAT) {
 			RTA_PUT(skb, map->action, 0, NULL);
 			if (tcf_action_dump(skb, exts->action, 0, 0) < 0)
 				goto rtattr_failure;
-			p_rta->rta_len = skb->tail - (u8*)p_rta;
+			p_rta->rta_len = skb_tail_pointer(skb) - (u8 *)p_rta;
 		} else if (map->police) {
 			RTA_PUT(skb, map->police, 0, NULL);
 			if (tcf_action_dump_old(skb, exts->action, 0, 0) < 0)
 				goto rtattr_failure;
-			p_rta->rta_len = skb->tail - (u8*)p_rta;
+			p_rta->rta_len = skb_tail_pointer(skb) - (u8 *)p_rta;
 		}
 	}
 #elif defined CONFIG_NET_CLS_POLICE
 	if (map->police && exts->police) {
-		struct rtattr * p_rta = (struct rtattr*) skb->tail;
+		struct rtattr *p_rta = (struct rtattr *)skb_tail_pointer(skb);
 
 		RTA_PUT(skb, map->police, 0, NULL);
 
 		if (tcf_police_dump(skb, exts->police) < 0)
 			goto rtattr_failure;
 
-		p_rta->rta_len = skb->tail - (u8*)p_rta;
+		p_rta->rta_len = skb_tail_pointer(skb) - (u8 *)p_rta;
 	}
 #endif
 	return 0;
diff --git a/net/sched/cls_basic.c b/net/sched/cls_basic.c
index 4a91f08..800ec2a 100644
--- a/net/sched/cls_basic.c
+++ b/net/sched/cls_basic.c
@@ -245,7 +245,7 @@ static int basic_dump(struct tcf_proto *tp, unsigned long fh,
 		      struct sk_buff *skb, struct tcmsg *t)
 {
 	struct basic_filter *f = (struct basic_filter *) fh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	if (f == NULL)
@@ -263,7 +263,7 @@ static int basic_dump(struct tcf_proto *tp, unsigned long fh,
 	    tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
 		goto rtattr_failure;
 
-	rta->rta_len = (skb->tail - b);
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 rtattr_failure:
diff --git a/net/sched/cls_fw.c b/net/sched/cls_fw.c
index 5dbb9d4..f5f3558 100644
--- a/net/sched/cls_fw.c
+++ b/net/sched/cls_fw.c
@@ -348,7 +348,7 @@ static int fw_dump(struct tcf_proto *tp, unsigned long fh,
 {
 	struct fw_head *head = (struct fw_head *)tp->root;
 	struct fw_filter *f = (struct fw_filter*)fh;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	if (f == NULL)
@@ -374,7 +374,7 @@ static int fw_dump(struct tcf_proto *tp, unsigned long fh,
 	if (tcf_exts_dump(skb, &f->exts, &fw_ext_map) < 0)
 		goto rtattr_failure;
 
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 
 	if (tcf_exts_dump_stats(skb, &f->exts, &fw_ext_map) < 0)
 		goto rtattr_failure;
diff --git a/net/sched/cls_route.c b/net/sched/cls_route.c
index abc47cc..1f94df3 100644
--- a/net/sched/cls_route.c
+++ b/net/sched/cls_route.c
@@ -562,7 +562,7 @@ static int route4_dump(struct tcf_proto *tp, unsigned long fh,
 		       struct sk_buff *skb, struct tcmsg *t)
 {
 	struct route4_filter *f = (struct route4_filter*)fh;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 	u32 id;
 
@@ -591,7 +591,7 @@ static int route4_dump(struct tcf_proto *tp, unsigned long fh,
 	if (tcf_exts_dump(skb, &f->exts, &route_ext_map) < 0)
 		goto rtattr_failure;
 
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 
 	if (tcf_exts_dump_stats(skb, &f->exts, &route_ext_map) < 0)
 		goto rtattr_failure;
diff --git a/net/sched/cls_rsvp.h b/net/sched/cls_rsvp.h
index 6f373b0..87ed6f3 100644
--- a/net/sched/cls_rsvp.h
+++ b/net/sched/cls_rsvp.h
@@ -593,7 +593,7 @@ static int rsvp_dump(struct tcf_proto *tp, unsigned long fh,
 {
 	struct rsvp_filter *f = (struct rsvp_filter*)fh;
 	struct rsvp_session *s;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 	struct tc_rsvp_pinfo pinfo;
 
@@ -623,7 +623,7 @@ static int rsvp_dump(struct tcf_proto *tp, unsigned long fh,
 	if (tcf_exts_dump(skb, &f->exts, &rsvp_ext_map) < 0)
 		goto rtattr_failure;
 
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 
 	if (tcf_exts_dump_stats(skb, &f->exts, &rsvp_ext_map) < 0)
 		goto rtattr_failure;
diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c
index 7563fdc..0537d60 100644
--- a/net/sched/cls_tcindex.c
+++ b/net/sched/cls_tcindex.c
@@ -448,7 +448,7 @@ static int tcindex_dump(struct tcf_proto *tp, unsigned long fh,
 {
 	struct tcindex_data *p = PRIV(tp);
 	struct tcindex_filter_result *r = (struct tcindex_filter_result *) fh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	DPRINTK("tcindex_dump(tp %p,fh 0x%lx,skb %p,t %p),p %p,r %p,b %p\n",
@@ -463,7 +463,7 @@ static int tcindex_dump(struct tcf_proto *tp, unsigned long fh,
 		RTA_PUT(skb,TCA_TCINDEX_SHIFT,sizeof(p->shift),&p->shift);
 		RTA_PUT(skb,TCA_TCINDEX_FALL_THROUGH,sizeof(p->fall_through),
 		    &p->fall_through);
-		rta->rta_len = skb->tail-b;
+		rta->rta_len = skb_tail_pointer(skb) - b;
 	} else {
 		if (p->perfect) {
 			t->tcm_handle = r-p->perfect;
@@ -486,7 +486,7 @@ static int tcindex_dump(struct tcf_proto *tp, unsigned long fh,
 
 		if (tcf_exts_dump(skb, &r->exts, &tcindex_ext_map) < 0)
 			goto rtattr_failure;
-		rta->rta_len = skb->tail-b;
+		rta->rta_len = skb_tail_pointer(skb) - b;
 
 		if (tcf_exts_dump_stats(skb, &r->exts, &tcindex_ext_map) < 0)
 			goto rtattr_failure;
diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c
index 695b340..fa11bb7 100644
--- a/net/sched/cls_u32.c
+++ b/net/sched/cls_u32.c
@@ -213,7 +213,7 @@ check_terminal:
 			off2 = 0;
 		}
 
-		if (ptr < skb->tail)
+		if (ptr < skb_tail_pointer(skb))
 			goto next_ht;
 	}
 
@@ -718,7 +718,7 @@ static int u32_dump(struct tcf_proto *tp, unsigned long fh,
 		     struct sk_buff *skb, struct tcmsg *t)
 {
 	struct tc_u_knode *n = (struct tc_u_knode*)fh;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	if (n == NULL)
@@ -765,7 +765,7 @@ static int u32_dump(struct tcf_proto *tp, unsigned long fh,
 #endif
 	}
 
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	if (TC_U32_KEY(n->handle))
 		if (tcf_exts_dump_stats(skb, &n->exts, &u32_ext_map) < 0)
 			goto rtattr_failure;
diff --git a/net/sched/ematch.c b/net/sched/ematch.c
index 959c306..63146d3 100644
--- a/net/sched/ematch.c
+++ b/net/sched/ematch.c
@@ -418,17 +418,19 @@ void tcf_em_tree_destroy(struct tcf_proto *tp, struct tcf_ematch_tree *tree)
 int tcf_em_tree_dump(struct sk_buff *skb, struct tcf_ematch_tree *tree, int tlv)
 {
 	int i;
-	struct rtattr * top_start = (struct rtattr*) skb->tail;
-	struct rtattr * list_start;
+	u8 *tail;
+	struct rtattr *top_start = (struct rtattr *)skb_tail_pointer(skb);
+	struct rtattr *list_start;
 
 	RTA_PUT(skb, tlv, 0, NULL);
 	RTA_PUT(skb, TCA_EMATCH_TREE_HDR, sizeof(tree->hdr), &tree->hdr);
 
-	list_start = (struct rtattr *) skb->tail;
+	list_start = (struct rtattr *)skb_tail_pointer(skb);
 	RTA_PUT(skb, TCA_EMATCH_TREE_LIST, 0, NULL);
 
+	tail = skb_tail_pointer(skb);
 	for (i = 0; i < tree->hdr.nmatches; i++) {
-		struct rtattr *match_start = (struct rtattr*) skb->tail;
+		struct rtattr *match_start = (struct rtattr *)tail;
 		struct tcf_ematch *em = tcf_em_get_match(tree, i);
 		struct tcf_ematch_hdr em_hdr = {
 			.kind = em->ops ? em->ops->kind : TCF_EM_CONTAINER,
@@ -447,11 +449,12 @@ int tcf_em_tree_dump(struct sk_buff *skb, struct tcf_ematch_tree *tree, int tlv)
 		} else if (em->datalen > 0)
 			RTA_PUT_NOHDR(skb, em->datalen, (void *) em->data);
 
-		match_start->rta_len = skb->tail - (u8*) match_start;
+		tail = skb_tail_pointer(skb);
+		match_start->rta_len = tail - (u8 *)match_start;
 	}
 
-	list_start->rta_len = skb->tail - (u8 *) list_start;
-	top_start->rta_len = skb->tail - (u8 *) top_start;
+	list_start->rta_len = tail - (u8 *)list_start;
+	top_start->rta_len = tail - (u8 *)top_start;
 
 	return 0;
 
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index ecbdc6b..7482a95 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -813,7 +813,7 @@ static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
 {
 	struct tcmsg *tcm;
 	struct nlmsghdr  *nlh;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct gnet_dump d;
 
 	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags);
@@ -847,7 +847,7 @@ static int tc_fill_qdisc(struct sk_buff *skb, struct Qdisc *q, u32 clid,
 	if (gnet_stats_finish_copy(&d) < 0)
 		goto rtattr_failure;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 nlmsg_failure:
@@ -1051,7 +1051,7 @@ static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
 {
 	struct tcmsg *tcm;
 	struct nlmsghdr  *nlh;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct gnet_dump d;
 	struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
 
@@ -1076,7 +1076,7 @@ static int tc_fill_tclass(struct sk_buff *skb, struct Qdisc *q,
 	if (gnet_stats_finish_copy(&d) < 0)
 		goto rtattr_failure;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 nlmsg_failure:
diff --git a/net/sched/sch_atm.c b/net/sched/sch_atm.c
index baca874..1d7bb16 100644
--- a/net/sched/sch_atm.c
+++ b/net/sched/sch_atm.c
@@ -631,7 +631,7 @@ static int atm_tc_dump_class(struct Qdisc *sch, unsigned long cl,
 {
 	struct atm_qdisc_data *p = PRIV(sch);
 	struct atm_flow_data *flow = (struct atm_flow_data *) cl;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	DPRINTK("atm_tc_dump_class(sch %p,[qdisc %p],flow %p,skb %p,tcm %p)\n",
@@ -661,7 +661,7 @@ static int atm_tc_dump_class(struct Qdisc *sch, unsigned long cl,
 
 		RTA_PUT(skb,TCA_ATM_EXCESS,sizeof(zero),&zero);
 	}
-	rta->rta_len = skb->tail-b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 rtattr_failure:
diff --git a/net/sched/sch_cbq.c b/net/sched/sch_cbq.c
index d83414d..be98a01 100644
--- a/net/sched/sch_cbq.c
+++ b/net/sched/sch_cbq.c
@@ -1465,7 +1465,7 @@ static int cbq_init(struct Qdisc *sch, struct rtattr *opt)
 
 static __inline__ int cbq_dump_rate(struct sk_buff *skb, struct cbq_class *cl)
 {
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 
 	RTA_PUT(skb, TCA_CBQ_RATE, sizeof(cl->R_tab->rate), &cl->R_tab->rate);
 	return skb->len;
@@ -1477,7 +1477,7 @@ rtattr_failure:
 
 static __inline__ int cbq_dump_lss(struct sk_buff *skb, struct cbq_class *cl)
 {
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_cbq_lssopt opt;
 
 	opt.flags = 0;
@@ -1502,7 +1502,7 @@ rtattr_failure:
 
 static __inline__ int cbq_dump_wrr(struct sk_buff *skb, struct cbq_class *cl)
 {
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_cbq_wrropt opt;
 
 	opt.flags = 0;
@@ -1520,7 +1520,7 @@ rtattr_failure:
 
 static __inline__ int cbq_dump_ovl(struct sk_buff *skb, struct cbq_class *cl)
 {
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_cbq_ovl opt;
 
 	opt.strategy = cl->ovl_strategy;
@@ -1537,7 +1537,7 @@ rtattr_failure:
 
 static __inline__ int cbq_dump_fopt(struct sk_buff *skb, struct cbq_class *cl)
 {
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_cbq_fopt opt;
 
 	if (cl->split || cl->defmap) {
@@ -1556,7 +1556,7 @@ rtattr_failure:
 #ifdef CONFIG_NET_CLS_POLICE
 static __inline__ int cbq_dump_police(struct sk_buff *skb, struct cbq_class *cl)
 {
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_cbq_police opt;
 
 	if (cl->police) {
@@ -1590,14 +1590,14 @@ static int cbq_dump_attr(struct sk_buff *skb, struct cbq_class *cl)
 static int cbq_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
 	struct cbq_sched_data *q = qdisc_priv(sch);
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	rta = (struct rtattr*)b;
 	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 	if (cbq_dump_attr(skb, &q->link) < 0)
 		goto rtattr_failure;
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 rtattr_failure:
@@ -1619,7 +1619,7 @@ cbq_dump_class(struct Qdisc *sch, unsigned long arg,
 	       struct sk_buff *skb, struct tcmsg *tcm)
 {
 	struct cbq_class *cl = (struct cbq_class*)arg;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	if (cl->tparent)
@@ -1633,7 +1633,7 @@ cbq_dump_class(struct Qdisc *sch, unsigned long arg,
 	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 	if (cbq_dump_attr(skb, cl) < 0)
 		goto rtattr_failure;
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 rtattr_failure:
diff --git a/net/sched/sch_hfsc.c b/net/sched/sch_hfsc.c
index 5197b6c..80e6f81 100644
--- a/net/sched/sch_hfsc.c
+++ b/net/sched/sch_hfsc.c
@@ -1363,7 +1363,7 @@ hfsc_dump_class(struct Qdisc *sch, unsigned long arg, struct sk_buff *skb,
 		struct tcmsg *tcm)
 {
 	struct hfsc_class *cl = (struct hfsc_class *)arg;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta = (struct rtattr *)b;
 
 	tcm->tcm_parent = cl->cl_parent ? cl->cl_parent->classid : TC_H_ROOT;
@@ -1374,7 +1374,7 @@ hfsc_dump_class(struct Qdisc *sch, unsigned long arg, struct sk_buff *skb,
 	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 	if (hfsc_dump_curves(skb, cl) < 0)
 		goto rtattr_failure;
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
  rtattr_failure:
@@ -1576,7 +1576,7 @@ static int
 hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb)
 {
 	struct hfsc_sched *q = qdisc_priv(sch);
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_hfsc_qopt qopt;
 
 	qopt.defcls = q->defcls;
diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
index f76c20c..c687388 100644
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -1110,7 +1110,7 @@ static int htb_init(struct Qdisc *sch, struct rtattr *opt)
 static int htb_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
 	struct htb_sched *q = qdisc_priv(sch);
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 	struct tc_htb_glob gopt;
 	spin_lock_bh(&sch->dev->queue_lock);
@@ -1123,12 +1123,12 @@ static int htb_dump(struct Qdisc *sch, struct sk_buff *skb)
 	rta = (struct rtattr *)b;
 	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 	RTA_PUT(skb, TCA_HTB_INIT, sizeof(gopt), &gopt);
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	spin_unlock_bh(&sch->dev->queue_lock);
 	return skb->len;
 rtattr_failure:
 	spin_unlock_bh(&sch->dev->queue_lock);
-	skb_trim(skb, skb->tail - skb->data);
+	skb_trim(skb, skb_tail_pointer(skb) - skb->data);
 	return -1;
 }
 
@@ -1136,7 +1136,7 @@ static int htb_dump_class(struct Qdisc *sch, unsigned long arg,
 			  struct sk_buff *skb, struct tcmsg *tcm)
 {
 	struct htb_class *cl = (struct htb_class *)arg;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 	struct tc_htb_opt opt;
 
@@ -1159,7 +1159,7 @@ static int htb_dump_class(struct Qdisc *sch, unsigned long arg,
 	opt.prio = cl->un.leaf.prio;
 	opt.level = cl->level;
 	RTA_PUT(skb, TCA_HTB_PARMS, sizeof(opt), &opt);
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	spin_unlock_bh(&sch->dev->queue_lock);
 	return skb->len;
 rtattr_failure:
diff --git a/net/sched/sch_ingress.c b/net/sched/sch_ingress.c
index cfe070e..d19f407 100644
--- a/net/sched/sch_ingress.c
+++ b/net/sched/sch_ingress.c
@@ -362,12 +362,12 @@ static void ingress_destroy(struct Qdisc *sch)
 
 static int ingress_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	rta = (struct rtattr *) b;
 	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 rtattr_failure:
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index 915f82a..2a9b1e4 100644
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -583,7 +583,7 @@ static void netem_destroy(struct Qdisc *sch)
 static int netem_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
 	const struct netem_sched_data *q = qdisc_priv(sch);
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta = (struct rtattr *) b;
 	struct tc_netem_qopt qopt;
 	struct tc_netem_corr cor;
@@ -611,7 +611,7 @@ static int netem_dump(struct Qdisc *sch, struct sk_buff *skb)
 	corrupt.correlation = q->corrupt_cor.rho;
 	RTA_PUT(skb, TCA_NETEM_CORRUPT, sizeof(corrupt), &corrupt);
 
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 
 	return skb->len;
 
diff --git a/net/sched/sch_prio.c b/net/sched/sch_prio.c
index de889f2..5b37110 100644
--- a/net/sched/sch_prio.c
+++ b/net/sched/sch_prio.c
@@ -271,7 +271,7 @@ static int prio_init(struct Qdisc *sch, struct rtattr *opt)
 static int prio_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
 	struct prio_sched_data *q = qdisc_priv(sch);
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_prio_qopt opt;
 
 	opt.bands = q->bands;
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c
index e369540..a511ba8 100644
--- a/net/sched/sch_sfq.c
+++ b/net/sched/sch_sfq.c
@@ -461,7 +461,7 @@ static void sfq_destroy(struct Qdisc *sch)
 static int sfq_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
 	struct sfq_sched_data *q = qdisc_priv(sch);
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_sfq_qopt opt;
 
 	opt.quantum = q->quantum;
diff --git a/net/sched/sch_tbf.c b/net/sched/sch_tbf.c
index f14692f..2318955 100644
--- a/net/sched/sch_tbf.c
+++ b/net/sched/sch_tbf.c
@@ -387,7 +387,7 @@ static void tbf_destroy(struct Qdisc *sch)
 static int tbf_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
 	struct tbf_sched_data *q = qdisc_priv(sch);
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 	struct tc_tbf_qopt opt;
 
@@ -403,7 +403,7 @@ static int tbf_dump(struct Qdisc *sch, struct sk_buff *skb)
 	opt.mtu = q->mtu;
 	opt.buffer = q->buffer;
 	RTA_PUT(skb, TCA_TBF_PARMS, sizeof(opt), &opt);
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 
 	return skb->len;