udp: Split receive from preparation and send in udp_sock_handler()

The receive part of udp_sock_handler() and udp_sock_handler_splice() is now
almost identical.  In preparation for merging that, split the receive part
of udp_sock_handler() from the part preparing and sending the frames for
sending on the tap interface.  The latter goes into a new udp_tap_send()
function.

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 2023-01-05 15:26:20 +11:00 committed by Stefano Brivio
parent 09c00f1d2a
commit 4eb54fd2e7

79
udp.c
View file

@ -880,51 +880,39 @@ static void udp_tap_send_passt(const struct ctx *c, struct mmsghdr *mmh, int n)
}
/**
* udp_sock_handler() - Handle new data from socket
* udp_tap_send() - Prepare UDP datagrams and send to tap interface
* @c: Execution context
* @ref: epoll reference
* @events: epoll events bitmap
* @start: Index of first datagram in udp[46]_l2_buf pool
* @n: Number of datagrams to send
* @dstport: Destination port number
* @v6: True if using IPv6
* @now: Current timestamp
*
* #syscalls recvmmsg
* Return: size of tap frame with headers
*/
void udp_sock_handler(const struct ctx *c, union epoll_ref ref, uint32_t events,
const struct timespec *now)
static void udp_tap_send(const struct ctx *c,
unsigned int start, unsigned int n,
in_port_t dstport, bool v6, const struct timespec *now)
{
in_port_t dstport = ref.r.p.udp.udp.port;
struct mmsghdr *tap_mmh, *sock_mmh;
int msg_bufs = 0, msg_i = 0;
ssize_t n, msg_len = 0;
struct mmsghdr *tap_mmh;
struct iovec *tap_iov;
ssize_t msg_len = 0;
unsigned int i;
if (events == EPOLLERR)
return;
if (ref.r.p.udp.udp.splice) {
udp_sock_handler_splice(c, ref, events, now);
return;
}
if (ref.r.p.udp.udp.v6) {
if (v6) {
tap_mmh = udp6_l2_mh_tap;
sock_mmh = udp6_l2_mh_sock;
tap_iov = udp6_l2_iov_tap;
} else {
tap_mmh = udp4_l2_mh_tap;
sock_mmh = udp4_l2_mh_sock;
tap_iov = udp4_l2_iov_tap;
}
n = recvmmsg(ref.r.s, sock_mmh, UDP_TAP_FRAMES, 0, NULL);
if (n <= 0)
return;
tap_mmh[0].msg_hdr.msg_iov = &tap_iov[0];
for (i = 0; i < (unsigned)n; i++) {
tap_mmh[0].msg_hdr.msg_iov = &tap_iov[start];
for (i = start; i < start + n; i++) {
size_t buf_len;
if (ref.r.p.udp.udp.v6)
if (v6)
buf_len = udp_update_hdr6(c, i, dstport, now);
else
buf_len = udp_update_hdr4(c, i, dstport, now);
@ -950,6 +938,43 @@ void udp_sock_handler(const struct ctx *c, union epoll_ref ref, uint32_t events,
udp_tap_send_passt(c, tap_mmh, msg_i + 1);
}
/**
* udp_sock_handler() - Handle new data from socket
* @c: Execution context
* @ref: epoll reference
* @events: epoll events bitmap
* @now: Current timestamp
*
* #syscalls recvmmsg
*/
void udp_sock_handler(const struct ctx *c, union epoll_ref ref, uint32_t events,
const struct timespec *now)
{
in_port_t dstport = ref.r.p.udp.udp.port;
bool v6 = ref.r.p.udp.udp.v6;
struct mmsghdr *sock_mmh;
ssize_t n;
if (events == EPOLLERR)
return;
if (ref.r.p.udp.udp.splice) {
udp_sock_handler_splice(c, ref, events, now);
return;
}
if (ref.r.p.udp.udp.v6)
sock_mmh = udp6_l2_mh_sock;
else
sock_mmh = udp4_l2_mh_sock;
n = recvmmsg(ref.r.s, sock_mmh, UDP_TAP_FRAMES, 0, NULL);
if (n <= 0)
return;
udp_tap_send(c, 0, n, dstport, v6, now);
}
/**
* udp_tap_handler() - Handle packets from tap
* @c: Execution context