1 files changed, 41 insertions, 1 deletions

diff --git a/net/rds/recv.c b/net/rds/recv.c
index b25bcfe411ca..de50e2126e40 100644
--- a/net/rds/recv.c
+++ b/net/rds/recv.c
@@ -577,6 +577,41 @@ out:
 	return ret;
 }
 
+static bool rds_recvmsg_zcookie(struct rds_sock *rs, struct msghdr *msg)
+{
+	struct rds_msg_zcopy_queue *q = &rs->rs_zcookie_queue;
+	struct rds_msg_zcopy_info *info = NULL;
+	struct rds_zcopy_cookies *done;
+	unsigned long flags;
+
+	if (!msg->msg_control)
+		return false;
+
+	if (!sock_flag(rds_rs_to_sk(rs), SOCK_ZEROCOPY) ||
+	    msg->msg_controllen < CMSG_SPACE(sizeof(*done)))
+		return false;
+
+	spin_lock_irqsave(&q->lock, flags);
+	if (!list_empty(&q->zcookie_head)) {
+		info = list_entry(q->zcookie_head.next,
+				  struct rds_msg_zcopy_info, rs_zcookie_next);
+		list_del(&info->rs_zcookie_next);
+	}
+	spin_unlock_irqrestore(&q->lock, flags);
+	if (!info)
+		return false;
+	done = &info->zcookies;
+	if (put_cmsg(msg, SOL_RDS, RDS_CMSG_ZCOPY_COMPLETION, sizeof(*done),
+		     done)) {
+		spin_lock_irqsave(&q->lock, flags);
+		list_add(&info->rs_zcookie_next, &q->zcookie_head);
+		spin_unlock_irqrestore(&q->lock, flags);
+		return false;
+	}
+	kfree(info);
+	return true;
+}
+
 int rds_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 		int msg_flags)
 {
@@ -594,6 +629,8 @@ 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 */
@@ -609,7 +646,9 @@ int rds_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 
 		if (!rds_next_incoming(rs, &inc)) {
 			if (nonblock) {
-				ret = -EAGAIN;
+				bool reaped = rds_recvmsg_zcookie(rs, msg);
+
+				ret = reaped ?  0 : -EAGAIN;
 				break;
 			}
 
@@ -658,6 +697,7 @@ int rds_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 			ret = -EFAULT;
 			goto out;
 		}
+		rds_recvmsg_zcookie(rs, msg);
 
 		rds_stats_inc(s_recv_delivered);