From fff1ebb269b6c18b21bc0ddab7dd8b0c5e68e0a1 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 20 May 2020 17:30:24 -0400 Subject: SUNRPC: Restructure svc_udp_recvfrom() Clean up. At this point, we are not ready yet to support bio_vecs in the UDP transport implementation. However, we can clean up svc_udp_recvfrom() to match the tracing and straight-lining recently changes made in svc_tcp_recvfrom(). Signed-off-by: Chuck Lever --- net/sunrpc/svcsock.c | 60 ++++++++++++++++++++++++++++++---------------------- 1 file changed, 35 insertions(+), 25 deletions(-) (limited to 'net/sunrpc/svcsock.c') diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 3e25511b800e..97d2b6f8c791 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -425,8 +425,15 @@ static int svc_udp_get_dest_address(struct svc_rqst *rqstp, return 0; } -/* - * Receive a datagram from a UDP socket. +/** + * svc_udp_recvfrom - Receive a datagram from a UDP socket. + * @rqstp: request structure into which to receive an RPC Call + * + * Called in a loop when XPT_DATA has been set. + * + * Returns: + * On success, the number of bytes in a received RPC Call, or + * %0 if a complete RPC Call message was not ready to return */ static int svc_udp_recvfrom(struct svc_rqst *rqstp) { @@ -460,20 +467,14 @@ static int svc_udp_recvfrom(struct svc_rqst *rqstp) svc_sock_setbufsize(svsk, serv->sv_nrthreads + 3); clear_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); - skb = NULL; err = kernel_recvmsg(svsk->sk_sock, &msg, NULL, 0, 0, MSG_PEEK | MSG_DONTWAIT); - if (err >= 0) - skb = skb_recv_udp(svsk->sk_sk, 0, 1, &err); - - if (skb == NULL) { - if (err != -EAGAIN) { - /* possibly an icmp error */ - dprintk("svc: recvfrom returned error %d\n", -err); - set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); - } - return 0; - } + if (err < 0) + goto out_recv_err; + skb = skb_recv_udp(svsk->sk_sk, 0, 1, &err); + if (!skb) + goto out_recv_err; + len = svc_addr_len(svc_addr(rqstp)); rqstp->rq_addrlen = len; if (skb->tstamp == 0) { @@ -484,26 +485,21 @@ static int svc_udp_recvfrom(struct svc_rqst *rqstp) sock_write_timestamp(svsk->sk_sk, skb->tstamp); set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); /* there may be more data... */ - len = skb->len; + len = skb->len; rqstp->rq_arg.len = len; + trace_svcsock_udp_recv(&svsk->sk_xprt, len); rqstp->rq_prot = IPPROTO_UDP; - if (!svc_udp_get_dest_address(rqstp, cmh)) { - net_warn_ratelimited("svc: received unknown control message %d/%d; dropping RPC reply datagram\n", - cmh->cmsg_level, cmh->cmsg_type); - goto out_free; - } + if (!svc_udp_get_dest_address(rqstp, cmh)) + goto out_cmsg_err; rqstp->rq_daddrlen = svc_addr_len(svc_daddr(rqstp)); if (skb_is_nonlinear(skb)) { /* we have to copy */ local_bh_disable(); - if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) { - local_bh_enable(); - /* checksum error */ - goto out_free; - } + if (csum_partial_copy_to_xdr(&rqstp->rq_arg, skb)) + goto out_bh_enable; local_bh_enable(); consume_skb(skb); } else { @@ -531,6 +527,20 @@ static int svc_udp_recvfrom(struct svc_rqst *rqstp) serv->sv_stats->netudpcnt++; return len; + +out_recv_err: + if (err != -EAGAIN) { + /* possibly an icmp error */ + set_bit(XPT_DATA, &svsk->sk_xprt.xpt_flags); + } + trace_svcsock_udp_recv_err(&svsk->sk_xprt, err); + return 0; +out_cmsg_err: + net_warn_ratelimited("svc: received unknown control message %d/%d; dropping RPC reply datagram\n", + cmh->cmsg_level, cmh->cmsg_type); + goto out_free; +out_bh_enable: + local_bh_enable(); out_free: kfree_skb(skb); return 0; -- cgit v1.2.3-59-g8ed1b