udp: Split send half of udp_sock_handler_splice() from the receive half

Move the part of udp_sock_handler_splice() concerned with sending out the
datagrams into a new udp_splice_sendfrom() helper.  This will make later
cleanups easier.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
This commit is contained in:
David Gibson 2022-11-30 15:13:15 +11:00 committed by Stefano Brivio
parent fc7f91e709
commit 2dec914209

76
udp.c
View file

@ -510,21 +510,26 @@ static in_port_t sa_port(bool v6, const void *sa)
}
/**
* udp_sock_handler_splice() - Handler for socket mapped to "spliced" connection
* udp_splice_sendfrom() - Send datagrams from given port to given port
* @c: Execution context
* @ref: epoll reference
* @events: epoll events bitmap
* @now: Current timestamp
* @start: Index of first datagram in udp[46]_l2_buf
* @n: Number of datagrams to send
* @src: Datagrams will be sent from this port (on origin side)
* @dst: Datagrams will be send to this port (on destination side)
* @v6: Send as IPv6?
* @from_ns: If true send from pasta ns to init, otherwise reverse
* @allow_new: If true create sending socket if needed, if false discard
* if no sending socket is available
* @now: Timestamp
*/
static void udp_sock_handler_splice(const struct ctx *c, union epoll_ref ref,
uint32_t events, const struct timespec *now)
static void udp_splice_sendfrom(const struct ctx *c, unsigned start, unsigned n,
in_port_t src, in_port_t dst,
bool v6, bool from_ns, bool allow_new,
const struct timespec *now)
{
in_port_t src, dst = ref.r.p.udp.udp.port;
int s, v6 = ref.r.p.udp.udp.v6, n, i;
struct mmsghdr *mmh_recv, *mmh_send;
if (!(events & EPOLLIN))
return;
unsigned int i;
int s;
if (v6) {
mmh_recv = udp6_l2_mh_sock;
@ -534,17 +539,10 @@ static void udp_sock_handler_splice(const struct ctx *c, union epoll_ref ref,
mmh_send = udp4_mh_splice;
}
n = recvmmsg(ref.r.s, mmh_recv, UDP_MAX_FRAMES, 0, NULL);
if (n <= 0)
return;
src = sa_port(v6, mmh_recv[0].msg_hdr.msg_name);
if (ref.r.p.udp.udp.ns) {
if (from_ns) {
src += c->udp.fwd_in.rdelta[src];
s = udp_splice_init[v6][src].sock;
if (!s && ref.r.p.udp.udp.orig)
if (!s && allow_new)
s = udp_splice_new(c, v6, src, false);
if (s < 0)
@ -555,7 +553,7 @@ static void udp_sock_handler_splice(const struct ctx *c, union epoll_ref ref,
} else {
src += c->udp.fwd_out.rdelta[src];
s = udp_splice_ns[v6][src].sock;
if (!s && ref.r.p.udp.udp.orig) {
if (!s && allow_new) {
struct udp_splice_new_ns_arg arg = {
c, v6, src, -1,
};
@ -570,9 +568,39 @@ static void udp_sock_handler_splice(const struct ctx *c, union epoll_ref ref,
udp_splice_ns[v6][src].ts = now->tv_sec;
}
for (i = 0; i < n; i++)
for (i = start; i < start + n; i++)
mmh_send[i].msg_hdr.msg_iov->iov_len = mmh_recv[i].msg_len;
sendmmsg(s, mmh_send + start, n, MSG_NOSIGNAL);
}
/**
* udp_sock_handler_splice() - Handler for socket mapped to "spliced" connection
* @c: Execution context
* @ref: epoll reference
* @events: epoll events bitmap
* @now: Current timestamp
*/
static void udp_sock_handler_splice(const struct ctx *c, union epoll_ref ref,
uint32_t events, const struct timespec *now)
{
in_port_t src, dst = ref.r.p.udp.udp.port;
int v6 = ref.r.p.udp.udp.v6, n;
struct mmsghdr *mmh_recv;
if (!(events & EPOLLIN))
return;
if (v6)
mmh_recv = udp6_l2_mh_sock;
else
mmh_recv = udp4_l2_mh_sock;
n = recvmmsg(ref.r.s, mmh_recv, UDP_MAX_FRAMES, 0, NULL);
if (n <= 0)
return;
if (v6) {
*((struct sockaddr_in6 *)&udp_splice_namebuf) =
((struct sockaddr_in6) {
@ -591,7 +619,9 @@ static void udp_sock_handler_splice(const struct ctx *c, union epoll_ref ref,
});
}
sendmmsg(s, mmh_send, n, MSG_NOSIGNAL);
src = sa_port(v6, mmh_recv[0].msg_hdr.msg_name);
udp_splice_sendfrom(c, 0, n, src, dst, v6,
ref.r.p.udp.udp.ns, ref.r.p.udp.udp.orig, now);
}
/**