From 925bba24e68a97b9c7926f2df4f405af883e6d0c Mon Sep 17 00:00:00 2001 From: Arjun Roy Date: Wed, 20 Jan 2021 16:41:47 -0800 Subject: [PATCH] tcp: Remove CMSG magic numbers for tcp_recvmsg(). At present, tcp_recvmsg() uses flags to track if any CMSGs are pending and what those CMSGs are. These flags are currently magic numbers, used only within tcp_recvmsg(). To prepare for receive timestamp support in tcp receive zerocopy, gently refactor these magic numbers into enums. Signed-off-by: Arjun Roy Signed-off-by: Jakub Kicinski --- net/ipv4/tcp.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index a1a17b64f8cd..7ba0bd0675cb 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -280,6 +280,12 @@ #include #include +/* Track pending CMSGs. */ +enum { + TCP_CMSG_INQ = 1, + TCP_CMSG_TS = 2 +}; + struct percpu_counter tcp_orphan_count; EXPORT_SYMBOL_GPL(tcp_orphan_count); @@ -2272,7 +2278,7 @@ static int tcp_recvmsg_locked(struct sock *sk, struct msghdr *msg, size_t len, goto out; if (tp->recvmsg_inq) - *cmsg_flags = 1; + *cmsg_flags = TCP_CMSG_INQ; timeo = sock_rcvtimeo(sk, nonblock); /* Urgent data needs to be handled specially. */ @@ -2453,7 +2459,7 @@ skip_copy: if (TCP_SKB_CB(skb)->has_rxtstamp) { tcp_update_recv_tstamps(skb, tss); - *cmsg_flags |= 2; + *cmsg_flags |= TCP_CMSG_TS; } if (used + offset < skb->len) @@ -2513,9 +2519,9 @@ int tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock, release_sock(sk); if (cmsg_flags && ret >= 0) { - if (cmsg_flags & 2) + if (cmsg_flags & TCP_CMSG_TS) tcp_recv_timestamp(msg, sk, &tss); - if (cmsg_flags & 1) { + if (cmsg_flags & TCP_CMSG_INQ) { inq = tcp_inq_hint(sk); put_cmsg(msg, SOL_TCP, TCP_CM_INQ, sizeof(inq), &inq); }