path: root/net/rds/recv.c
diff options
authorSowmini Varadhan <sowmini.varadhan@oracle.com>2018-02-15 10:49:35 -0800
committerDavid S. Miller <davem@davemloft.net>2018-02-16 16:04:17 -0500
commit01883eda72bd3f0a6c81447e4f223de14033fd9d (patch)
tree1d70322d05664e531520ae30d47ee5ef7267c644 /net/rds/recv.c
parent28190752c709272de3c2b6b092029da3f1614c5a (diff)
rds: support for zcopy completion notification
RDS removes a datagram (rds_message) from the retransmit queue when an ACK is received. The ACK indicates that the receiver has queued the RDS datagram, so that the sender can safely forget the datagram. When all references to the rds_message are quiesced, rds_message_purge is called to release resources used by the rds_message If the datagram to be removed had pinned pages set up, add an entry to the rs->rs_znotify_queue so that the notifcation will be sent up via rds_rm_zerocopy_callback() when the rds_message is eventually freed by rds_message_purge. rds_rm_zerocopy_callback() attempts to batch the number of cookies sent with each notification to a max of SO_EE_ORIGIN_MAX_ZCOOKIES. This is achieved by checking the tail skb in the sk_error_queue: if this has room for one more cookie, the cookie from the current notification is added; else a new skb is added to the sk_error_queue. Every invocation of rds_rm_zerocopy_callback() will trigger a ->sk_error_report to notify the application. Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com> Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/rds/recv.c')
1 files changed, 2 insertions, 0 deletions
diff --git a/net/rds/recv.c b/net/rds/recv.c
index b25bcfe411ca..b080961464df 100644
--- a/net/rds/recv.c
+++ b/net/rds/recv.c
@@ -594,6 +594,8 @@ int rds_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
if (msg_flags & MSG_OOB)
goto out;
+ if (msg_flags & MSG_ERRQUEUE)
+ return sock_recv_errqueue(sk, msg, size, SOL_IP, IP_RECVERR);
while (1) {
/* If there are pending notifications, do those - and nothing else */