net: Add and use skb_mark_not_on_list().

An SKB is not on a list if skb->next is NULL.

Codify this convention into a helper function and use it
where we are dequeueing an SKB and need to mark it as such.

Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 89283b7..c4c9e3f 100644 (file)
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1339,6 +1339,11 @@ static inline void skb_zcopy_abort(struct sk_buff *skb)
        }
 }
 
+static inline void skb_mark_not_on_list(struct sk_buff *skb)
+{
+       skb->next = NULL;
+}
+
 /**
  *     skb_queue_empty - check if a queue is empty
  *     @list: queue head

diff --git a/net/core/dev.c b/net/core/dev.c
index ca78dc5..f76dd7e 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3231,7 +3231,7 @@ struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *de
        while (skb) {
                struct sk_buff *next = skb->next;
 
-               skb->next = NULL;
+               skb_mark_not_on_list(skb);
                rc = xmit_one(skb, dev, txq, next != NULL);
                if (unlikely(!dev_xmit_complete(rc))) {
                        skb->next = next;
@@ -3331,7 +3331,7 @@ struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *d
 
        for (; skb != NULL; skb = next) {
                next = skb->next;
-               skb->next = NULL;
+               skb_mark_not_on_list(skb);
 
                /* in case skb wont be segmented, point to itself */
                skb->prev = skb;
@@ -5296,7 +5296,7 @@ static void __napi_gro_flush_chain(struct napi_struct *napi, u32 index,
                if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
                        return;
                list_del(&skb->list);
-               skb->next = NULL;
+               skb_mark_not_on_list(skb);
                napi_gro_complete(skb);
                napi->gro_hash[index].count--;
        }
@@ -5482,7 +5482,7 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff
 
        if (pp) {
                list_del(&pp->list);
-               pp->next = NULL;
+               skb_mark_not_on_list(pp);
                napi_gro_complete(pp);
                napi->gro_hash[hash].count--;
        }

diff --git a/net/core/sock.c b/net/core/sock.c
index 3730eb8..8537b6c 100644 (file)
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -2332,7 +2332,7 @@ static void __release_sock(struct sock *sk)
                        next = skb->next;
                        prefetch(next);
                        WARN_ON_ONCE(skb_dst_is_noref(skb));
-                       skb->next = NULL;
+                       skb_mark_not_on_list(skb);
                        sk_backlog_rcv(sk, skb);
 
                        cond_resched();

diff --git a/net/ieee802154/6lowpan/reassembly.c b/net/ieee802154/6lowpan/reassembly.c
index e7857a8..09ffbf5 100644 (file)
--- a/net/ieee802154/6lowpan/reassembly.c
+++ b/net/ieee802154/6lowpan/reassembly.c
@@ -260,7 +260,7 @@ static int lowpan_frag_reasm(struct lowpan_frag_queue *fq, struct sk_buff *prev,
        }
        sub_frag_mem_limit(fq->q.net, sum_truesize);
 
-       head->next = NULL;
+       skb_mark_not_on_list(head);
        head->dev = ldev;
        head->tstamp = fq->q.stamp;
 

diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c
index 330f623..cab3e4a 100644 (file)
--- a/net/ipv4/ip_fragment.c
+++ b/net/ipv4/ip_fragment.c
@@ -623,7 +623,7 @@ static int ip_frag_reasm(struct ipq *qp, struct sk_buff *skb,
        sub_frag_mem_limit(qp->q.net, head->truesize);
 
        *nextp = NULL;
-       head->next = NULL;
+       skb_mark_not_on_list(head);
        head->prev = NULL;
        head->dev = dev;
        head->tstamp = qp->q.stamp;

diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index 3196cf5..eba7f38 100644 (file)
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -535,7 +535,7 @@ static void ip_sublist_rcv_finish(struct list_head *head)
                /* Handle ip{6}_forward case, as sch_direct_xmit have
                 * another kind of SKB-list usage (see validate_xmit_skb_list)
                 */
-               skb->next = NULL;
+               skb_mark_not_on_list(skb);
                dst_input(skb);
        }
 }

diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 9c4e72e..c09219e 100644 (file)
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -278,7 +278,7 @@ static int ip_finish_output_gso(struct net *net, struct sock *sk,
                struct sk_buff *nskb = segs->next;
                int err;
 
-               segs->next = NULL;
+               skb_mark_not_on_list(segs);
                err = ip_fragment(net, sk, segs, mtu, ip_finish_output2);
 
                if (err && ret == 0)
@@ -684,7 +684,7 @@ int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
 
                        skb = frag;
                        frag = skb->next;
-                       skb->next = NULL;
+                       skb_mark_not_on_list(skb);
                }
 
                if (err == 0) {

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 16f200f..9a8934a 100644 (file)
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -727,7 +727,7 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
 
                        skb = frag;
                        frag = skb->next;
-                       skb->next = NULL;
+                       skb_mark_not_on_list(skb);
                }
 
                kfree(tmp_hdr);

diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c
index 2a14d8b..00e2000 100644 (file)
--- a/net/ipv6/netfilter/nf_conntrack_reasm.c
+++ b/net/ipv6/netfilter/nf_conntrack_reasm.c
@@ -449,7 +449,7 @@ nf_ct_frag6_reasm(struct frag_queue *fq, struct sk_buff *prev,  struct net_devic
        sub_frag_mem_limit(fq->q.net, head->truesize);
 
        head->ignore_df = 1;
-       head->next = NULL;
+       skb_mark_not_on_list(head);
        head->dev = dev;
        head->tstamp = fq->q.stamp;
        ipv6_hdr(head)->payload_len = htons(payload_len);

diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
index 5c5b4f7..f1b1ff3 100644 (file)
--- a/net/ipv6/reassembly.c
+++ b/net/ipv6/reassembly.c
@@ -388,7 +388,7 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev,
        }
        sub_frag_mem_limit(fq->q.net, sum_truesize);
 
-       head->next = NULL;
+       skb_mark_not_on_list(head);
        head->dev = dev;
        head->tstamp = fq->q.stamp;
        ipv6_hdr(head)->payload_len = htons(payload_len);

diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index ea4ba55..5207eb8 100644 (file)
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -764,7 +764,7 @@ __nfqnl_enqueue_packet_gso(struct net *net, struct nfqnl_instance *queue,
                return ret;
        }
 
-       skb->next = NULL;
+       skb_mark_not_on_list(skb);
 
        entry_seg = nf_queue_entry_dup(entry);
        if (entry_seg) {

diff --git a/net/rxrpc/input.c b/net/rxrpc/input.c
index cfdc199..ee8e7e1 100644 (file)
--- a/net/rxrpc/input.c
+++ b/net/rxrpc/input.c
@@ -259,7 +259,7 @@ static void rxrpc_rotate_tx_window(struct rxrpc_call *call, rxrpc_seq_t to,
        while (list) {
                skb = list;
                list = skb->next;
-               skb->next = NULL;
+               skb_mark_not_on_list(skb);
                rxrpc_free_skb(skb, rxrpc_skb_tx_freed);
        }
 }

diff --git a/net/sched/sch_cake.c b/net/sched/sch_cake.c
index c07c30b..dc53929 100644 (file)
--- a/net/sched/sch_cake.c
+++ b/net/sched/sch_cake.c
@@ -812,7 +812,7 @@ static struct sk_buff *dequeue_head(struct cake_flow *flow)
 
        if (skb) {
                flow->head = skb->next;
-               skb->next = NULL;
+               skb_mark_not_on_list(skb);
        }
 
        return skb;
@@ -1252,7 +1252,7 @@ found:
        else
                flow->head = elig_ack->next;
 
-       elig_ack->next = NULL;
+       skb_mark_not_on_list(elig_ack);
 
        return elig_ack;
 }
@@ -1675,7 +1675,7 @@ static s32 cake_enqueue(struct sk_buff *skb, struct Qdisc *sch,
 
                while (segs) {
                        nskb = segs->next;
-                       segs->next = NULL;
+                       skb_mark_not_on_list(segs);
                        qdisc_skb_cb(segs)->pkt_len = segs->len;
                        cobalt_set_enqueue_time(segs, now);
                        get_cobalt_cb(segs)->adjusted_len = cake_overhead(q,

diff --git a/net/sched/sch_fq.c b/net/sched/sch_fq.c
index 4808713..b27ba36 100644 (file)
--- a/net/sched/sch_fq.c
+++ b/net/sched/sch_fq.c
@@ -319,7 +319,7 @@ static struct sk_buff *fq_dequeue_head(struct Qdisc *sch, struct fq_flow *flow)
 
        if (skb) {
                flow->head = skb->next;
-               skb->next = NULL;
+               skb_mark_not_on_list(skb);
                flow->qlen--;
                qdisc_qstats_backlog_dec(sch, skb);
                sch->q.qlen--;

diff --git a/net/sched/sch_fq_codel.c b/net/sched/sch_fq_codel.c
index 6c0a9d5..cd04d40 100644 (file)
--- a/net/sched/sch_fq_codel.c
+++ b/net/sched/sch_fq_codel.c
@@ -124,7 +124,7 @@ static inline struct sk_buff *dequeue_head(struct fq_codel_flow *flow)
        struct sk_buff *skb = flow->head;
 
        flow->head = skb->next;
-       skb->next = NULL;
+       skb_mark_not_on_list(skb);
        return skb;
 }
 

diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index 69078c8..a64132a 100644 (file)
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -184,7 +184,7 @@ static void try_bulk_dequeue_skb(struct Qdisc *q,
                skb = nskb;
                (*packets)++; /* GSO counts as one pkt */
        }
-       skb->next = NULL;
+       skb_mark_not_on_list(skb);
 }
 
 /* This variant of try_bulk_dequeue_skb() makes sure
@@ -210,7 +210,7 @@ static void try_bulk_dequeue_skb_slow(struct Qdisc *q,
                skb = nskb;
        } while (++cnt < 8);
        (*packets) += cnt;
-       skb->next = NULL;
+       skb_mark_not_on_list(skb);
 }
 
 /* Note that dequeue_skb can possibly return a SKB list (via skb->next).

diff --git a/net/sched/sch_hhf.c b/net/sched/sch_hhf.c
index c3a8388..9d6a476 100644 (file)
--- a/net/sched/sch_hhf.c
+++ b/net/sched/sch_hhf.c
@@ -330,7 +330,7 @@ static struct sk_buff *dequeue_head(struct wdrr_bucket *bucket)
        struct sk_buff *skb = bucket->head;
 
        bucket->head = skb->next;
-       skb->next = NULL;
+       skb_mark_not_on_list(skb);
        return skb;
 }
 

diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index b9541ce..506e196 100644 (file)
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -568,7 +568,7 @@ finish_segs:
        if (segs) {
                while (segs) {
                        skb2 = segs->next;
-                       segs->next = NULL;
+                       skb_mark_not_on_list(segs);
                        qdisc_skb_cb(segs)->pkt_len = segs->len;
                        last_len = segs->len;
                        rc = qdisc_enqueue(segs, sch, to_free);

diff --git a/net/sched/sch_tbf.c b/net/sched/sch_tbf.c
index 6f74a42..a4530e8 100644 (file)
--- a/net/sched/sch_tbf.c
+++ b/net/sched/sch_tbf.c
@@ -162,7 +162,7 @@ static int tbf_segment(struct sk_buff *skb, struct Qdisc *sch,
        nb = 0;
        while (segs) {
                nskb = segs->next;
-               segs->next = NULL;
+               skb_mark_not_on_list(segs);
                qdisc_skb_cb(segs)->pkt_len = segs->len;
                len += segs->len;
                ret = qdisc_enqueue(segs, q->qdisc, to_free);

diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
index 418f03d..9189104 100644 (file)
--- a/net/tipc/bearer.c
+++ b/net/tipc/bearer.c
@@ -577,7 +577,7 @@ static int tipc_l2_rcv_msg(struct sk_buff *skb, struct net_device *dev,
                rcu_dereference_rtnl(orig_dev->tipc_ptr);
        if (likely(b && test_bit(0, &b->up) &&
                   (skb->pkt_type <= PACKET_MULTICAST))) {
-               skb->next = NULL;
+               skb_mark_not_on_list(skb);
                tipc_rcv(dev_net(b->pt.dev), skb, b);
                rcu_read_unlock();
                return NET_RX_SUCCESS;

diff --git a/net/xfrm/xfrm_device.c b/net/xfrm/xfrm_device.c
index 5611b75..260fbba 100644 (file)
--- a/net/xfrm/xfrm_device.c
+++ b/net/xfrm/xfrm_device.c
@@ -99,7 +99,7 @@ struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t featur
 
        do {
                struct sk_buff *nskb = skb2->next;
-               skb2->next = NULL;
+               skb_mark_not_on_list(skb2);
 
                xo = xfrm_offload(skb2);
                xo->flags |= XFRM_DEV_RESUME;

diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index 45ba07a..2d42cb0 100644 (file)
--- a/net/xfrm/xfrm_output.c
+++ b/net/xfrm/xfrm_output.c
@@ -189,7 +189,7 @@ static int xfrm_output_gso(struct net *net, struct sock *sk, struct sk_buff *skb
                struct sk_buff *nskb = segs->next;
                int err;
 
-               segs->next = NULL;
+               skb_mark_not_on_list(segs);
                err = xfrm_output2(net, sk, segs);
 
                if (unlikely(err)) {