David Laight noticed the support for MSG_MORE with datamsg->force_day
didn't really work as we expected, as the first msg with MSG_MORE set
would always block the following chunks' dequeuing.
This Patch is to rewrite it by saving the MSG_MORE flag into assoc as
Divid Laight suggested.
asoc->force_delay is used to save MSG_MORE flag before a msg is sent.
Once this msg is queued, asoc->force_delay is set back to 0, so that
it will not affect other places flushing out queue.
asoc->force_delay works as a 'local param' here as the msg sending is
under protection of sock lock. It would make sctp's MSG_MORE work as
tcp's.
Fixes: 4ea0c32f5f42 ("sctp: add support for MSG_MORE")
Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx>
---
include/net/sctp/structs.h | 2 +-
net/sctp/output.c | 2 +-
net/sctp/socket.c | 3 ++-
3 files changed, 4 insertions(+), 3 deletions(-)
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index a244db5..3378c02 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -497,7 +497,6 @@ struct sctp_datamsg {
/* Did the messenge fail to send? */
int send_error;
u8 send_failed:1,
- force_delay:1,
can_delay; /* should this message be Nagle delayed */
};
@@ -1876,6 +1875,7 @@ struct sctp_association {
__u8 need_ecne:1, /* Need to send an ECNE Chunk? */
temp:1, /* Is it a temporary association? */
+ force_delay:1,
prsctp_enable:1,
reconf_enable:1;
diff --git a/net/sctp/output.c b/net/sctp/output.c
index 85406d5..5f6acac 100644
--- a/net/sctp/output.c
+++ b/net/sctp/output.c
@@ -705,7 +705,7 @@ static sctp_xmit_t sctp_packet_can_append_data(struct sctp_packet *packet,
*/
if ((sctp_sk(asoc->base.sk)->nodelay || inflight == 0) &&
- !chunk->msg->force_delay)
+ !asoc->force_delay)
/* Nothing unacked */
return SCTP_XMIT_OK;
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 465a9c8..d62cf9e 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1964,7 +1964,7 @@ static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)
err = PTR_ERR(datamsg);
goto out_free;
}
- datamsg->force_delay = !!(msg->msg_flags & MSG_MORE);
+ asoc->force_delay = !!(msg->msg_flags & MSG_MORE);
/* Now send the (possibly) fragmented message. */
list_for_each_entry(chunk, &datamsg->chunks, frag_list) {
@@ -1982,6 +1982,7 @@ static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len)
* breaks.
*/
err = sctp_primitive_SEND(net, asoc, datamsg);
+ asoc->force_delay = 0;
/* Did the lower layer accept the chunk? */
if (err) {
sctp_datamsg_free(datamsg);
--
2.1.0
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