@@ -355,7 +355,6 @@ int mptcp_is_enabled(struct net *net);
void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow,
struct mptcp_options_received *mp_opt);
bool mptcp_subflow_data_available(struct sock *sk);
-int mptcp_subflow_discard_data(struct sock *sk, unsigned limit);
void __init mptcp_subflow_init(void);
/* called with sk socket lock held */
@@ -817,50 +817,20 @@ static enum mapping_status get_mapping_status(struct sock *ssk,
return MAPPING_OK;
}
-static int subflow_read_actor(read_descriptor_t *desc,
- struct sk_buff *skb,
- unsigned int offset, size_t len)
+static void mptcp_subflow_discard_data(struct sock *ssk, struct sk_buff *skb,
+ unsigned limit)
{
- size_t copy_len = min(desc->count, len);
+ struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
+ bool fin = TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN;
+ u32 incr;
- desc->count -= copy_len;
+ incr = limit >= skb->len ? skb->len + fin : limit;
- pr_debug("flushed %zu bytes, %zu left", copy_len, desc->count);
- return copy_len;
-}
-
-int mptcp_subflow_discard_data(struct sock *ssk, unsigned limit)
-{
- struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
- u32 map_remaining;
- size_t delta;
-
- map_remaining = subflow->map_data_len -
- mptcp_subflow_get_map_offset(subflow);
- delta = min_t(size_t, limit, map_remaining);
-
- /* discard mapped data */
- pr_debug("discarding %zu bytes, current map len=%d", delta,
- map_remaining);
- if (delta) {
- read_descriptor_t desc = {
- .count = delta,
- };
- int ret;
-
- ret = tcp_read_sock(ssk, &desc, subflow_read_actor);
- if (ret < 0) {
- ssk->sk_err = -ret;
- return ret;
- }
- if (ret < delta)
- return 0;
- if (delta == map_remaining) {
- subflow->data_avail = 0;
- subflow->map_valid = 0;
- }
- }
- return 0;
+ pr_debug("discarding=%d len=%d seq=%d", incr, skb->len,
+ subflow->map_subflow_seq);
+ tcp_sk(ssk)->copied_seq += incr;
+ if (incr >= skb->len)
+ sk_eat_skb(ssk, skb);
}
static bool subflow_check_data_avail(struct sock *ssk)
@@ -935,9 +905,7 @@ static bool subflow_check_data_avail(struct sock *ssk)
/* only accept in-sequence mapping. Old values are spurious
* retransmission
*/
- if (mptcp_subflow_discard_data(ssk, old_ack - ack_seq))
- goto fatal;
- return false;
+ mptcp_subflow_discard_data(ssk, skb, old_ack - ack_seq);
}
return true;
There is no need to use the tcp_read_sock(), we can simply drop the skb. Additionally try to look at next buffer for in order data. This both simplify the code and avoid unneeded indirect calls. Signed-off-by: Paolo Abeni <pabeni@redhat.com> --- RFC -> v1: - added changelog, continue looping on drop (Florian) --- net/mptcp/protocol.h | 1 - net/mptcp/subflow.c | 56 ++++++++++---------------------------------- 2 files changed, 12 insertions(+), 45 deletions(-)