We have separate mmsghdr arrays for splicing IPv4 and IPv6 packets, where
the only difference is that they point to different sockaddr buffers for
the destination address.
Unify these by having the common array point at a sockaddr_inany as the
address. This does mean slightly more work when we're about to splice,
because we need to write the whole socket address, rather than just the
port. However it removes 32 mmsghdr structures and we're going to need
more flexibility constructing that target address for the flow table.
Because future changes might mean that the address isn't always loopback,
change the name of the common address from *_localname to udp_splicename.
Signed-off-by: David Gibson <david(a)gibson.dropbear.id.au>
---
udp.c | 47 ++++++++++++++++++++---------------------------
1 file changed, 20 insertions(+), 27 deletions(-)
diff --git a/udp.c b/udp.c
index 663a2dce..b4ea2b35 100644
--- a/udp.c
+++ b/udp.c
@@ -235,18 +235,10 @@ static struct mmsghdr udp4_mh_recv [UDP_MAX_FRAMES];
static struct mmsghdr udp6_mh_recv [UDP_MAX_FRAMES];
/* IOVs and msghdr arrays for sending "spliced" datagrams to sockets */
-static struct sockaddr_in udp4_spliceto = {
- .sin_family = AF_INET,
- .sin_addr = IN4ADDR_LOOPBACK_INIT,
-};
-static struct sockaddr_in6 udp6_spliceto = {
- .sin6_family = AF_INET6,
- .sin6_addr = IN6ADDR_LOOPBACK_INIT,
-};
+static union sockaddr_inany udp_spliceto;
static struct iovec udp_iov_splice [UDP_MAX_FRAMES];
-static struct mmsghdr udp4_mh_splice [UDP_MAX_FRAMES];
-static struct mmsghdr udp6_mh_splice [UDP_MAX_FRAMES];
+static struct mmsghdr udp_mh_splice [UDP_MAX_FRAMES];
/* IOVs for L2 frames */
static struct iovec udp4_l2_iov [UDP_MAX_FRAMES][UDP_NUM_IOVS];
@@ -523,7 +515,7 @@ static unsigned udp_splice_send(const struct ctx *c, size_t start,
size_t n,
const struct timespec *now)
{
in_port_t src = udp_meta[start].splicesrc;
- struct mmsghdr *mmh_recv, *mmh_send;
+ struct mmsghdr *mmh_recv;
unsigned int i = start;
int s;
@@ -532,16 +524,22 @@ static unsigned udp_splice_send(const struct ctx *c, size_t start,
size_t n,
if (ref.udp.v6) {
mmh_recv = udp6_mh_recv;
- mmh_send = udp6_mh_splice;
- udp6_spliceto.sin6_port = htons(dst);
+ udp_spliceto.sa6 = (struct sockaddr_in6) {
+ .sin6_family = AF_INET6,
+ .sin6_addr = in6addr_loopback,
+ .sin6_port = htons(dst),
+ };
} else {
mmh_recv = udp4_mh_recv;
- mmh_send = udp4_mh_splice;
- udp4_spliceto.sin_port = htons(dst);
+ udp_spliceto.sa4 = (struct sockaddr_in) {
+ .sin_family = AF_INET,
+ .sin_addr = in4addr_loopback,
+ .sin_port = htons(dst),
+ };
}
do {
- mmh_send[i].msg_hdr.msg_iov->iov_len = mmh_recv[i].msg_len;
+ udp_mh_splice[i].msg_hdr.msg_iov->iov_len = mmh_recv[i].msg_len;
if (++i >= n)
break;
@@ -579,7 +577,7 @@ static unsigned udp_splice_send(const struct ctx *c, size_t start,
size_t n,
udp_splice_ns[ref.udp.v6][src].ts = now->tv_sec;
}
- sendmmsg(s, mmh_send + start, i - start, MSG_NOSIGNAL);
+ sendmmsg(s, udp_mh_splice + start, i - start, MSG_NOSIGNAL);
out:
return i - start;
}
@@ -1094,20 +1092,15 @@ static void udp_splice_iov_init(void)
int i;
for (i = 0; i < UDP_MAX_FRAMES; i++) {
- struct msghdr *mh4 = &udp4_mh_splice[i].msg_hdr;
- struct msghdr *mh6 = &udp6_mh_splice[i].msg_hdr;
-
- mh4->msg_name = &udp4_spliceto;
- mh4->msg_namelen = sizeof(udp4_spliceto);
+ struct msghdr *mh = &udp_mh_splice[i].msg_hdr;
- mh6->msg_name = &udp6_spliceto;
- mh6->msg_namelen = sizeof(udp6_spliceto);
+ mh->msg_name = &udp_spliceto;
+ mh->msg_namelen = sizeof(udp_spliceto);
udp_iov_splice[i].iov_base = udp_payload[i].data;
- mh4->msg_iov = &udp_iov_splice[i];
- mh6->msg_iov = &udp_iov_splice[i];
- mh4->msg_iovlen = mh6->msg_iovlen = 1;
+ mh->msg_iov = &udp_iov_splice[i];
+ mh->msg_iovlen = 1;
}
}
--
2.45.2