static void
vubr_queue_set_started(VuDev *dev, int qidx, bool started)
{
VuVirtq *vq = vu_get_queue(dev, qidx);
if (qidx % 2 == 1) {
vu_set_queue_handler(dev, vq, started ? vubr_handle_tx : NULL);
}
}
static void
vubr_queue_set_started(VuDev *dev, int qidx, bool started)
{
VubrDev *vubr = container_of(dev, VubrDev, vudev);
VuVirtq *vq = vu_get_queue(dev, qidx);
if (started && vubr->notifier.fd >= 0) {
vu_set_queue_host_notifier(dev, vq, vubr->notifier.fd,
getpagesize(),
qidx * getpagesize());
}
if (qidx % 2 == 1) {
vu_set_queue_handler(dev, vq, started ? vubr_handle_tx : NULL);
}
}
static void
vubr_backend_recv_cb(int sock, void *ctx)
{
VubrDev *vubr = (VubrDev *) ctx;
VuDev *dev = &vubr->vudev;
VuVirtq *vq = vu_get_queue(dev, 0);
VuVirtqElement *elem = NULL;
struct iovec mhdr_sg[VIRTQUEUE_MAX_SIZE];
struct virtio_net_hdr_mrg_rxbuf mhdr;
unsigned mhdr_cnt = 0;
int hdrlen = vubr->hdrlen;
int i = 0;
struct virtio_net_hdr hdr = {
.flags = 0,
.gso_type = VIRTIO_NET_HDR_GSO_NONE
};
DPRINT("\n\n *** IN UDP RECEIVE CALLBACK ***\n\n");
DPRINT(" hdrlen = %d\n", hdrlen);
if (!vu_queue_enabled(dev, vq) ||
!vu_queue_started(dev, vq) ||
!vu_queue_avail_bytes(dev, vq, hdrlen, 0)) {
DPRINT("Got UDP packet, but no available descriptors on RX virtq.\n");
return;
}
while (1) {
struct iovec *sg;
ssize_t ret, total = 0;
unsigned int num;
elem = vu_queue_pop(dev, vq, sizeof(VuVirtqElement));
if (!elem) {
break;
}
if (elem->in_num < 1) {
fprintf(stderr, "virtio-net contains no in buffers\n");
break;
}
sg = elem->in_sg;
num = elem->in_num;
if (i == 0) {
if (hdrlen == 12) {
mhdr_cnt = iov_copy(mhdr_sg, ARRAY_SIZE(mhdr_sg),
sg, elem->in_num,
offsetof(typeof(mhdr), num_buffers),
sizeof(mhdr.num_buffers));
}
iov_from_buf(sg, elem->in_num, 0, &hdr, sizeof hdr);
total += hdrlen;
ret = iov_discard_front(&sg, &num, hdrlen);
assert(ret == hdrlen);
}
struct msghdr msg = {
.msg_name = (struct sockaddr *) &vubr->backend_udp_dest,
.msg_namelen = sizeof(struct sockaddr_in),
.msg_iov = sg,
.msg_iovlen = num,
.msg_flags = MSG_DONTWAIT,
};
do {
ret = recvmsg(vubr->backend_udp_sock, &msg, 0);
} while (ret == -1 && (errno == EINTR));
if (i == 0) {
iov_restore_front(elem->in_sg, sg, hdrlen);
}
if (ret == -1) {
if (errno == EWOULDBLOCK) {
vu_queue_rewind(dev, vq, 1);
break;
}
vubr_die("recvmsg()");
}
total += ret;
iov_truncate(elem->in_sg, elem->in_num, total);
vu_queue_fill(dev, vq, elem, total, i++);
free(elem);
elem = NULL;
break; /* could loop if DONTWAIT worked? */
}
if (mhdr_cnt) {
mhdr.num_buffers = i;
iov_from_buf(mhdr_sg, mhdr_cnt,
0,
&mhdr.num_buffers, sizeof mhdr.num_buffers);
}
vu_queue_flush(dev, vq, i);
vu_queue_notify(dev, vq);
free(elem);
}
static void
vubr_receive_cb(int sock, void *ctx)
{
VubrDev *vubr = (VubrDev *)ctx;
if (!vu_dispatch(&vubr->vudev)) {
fprintf(stderr, "Error while dispatching\n");
}
}
typedef struct WatchData {
VuDev *dev;
vu_watch_cb cb;
void *data;
} WatchData;
static void
watch_cb(int sock, void *ctx)
{
struct WatchData *wd = ctx;
wd->cb(wd->dev, VU_WATCH_IN, wd->data);
}
static void
vubr_set_watch(VuDev *dev, int fd, int condition,
vu_watch_cb cb, void *data)
{
VubrDev *vubr = container_of(dev, VubrDev, vudev);
static WatchData watches[FD_SETSIZE];
struct WatchData *wd = &watches[fd];
wd->cb = cb;
wd->data = data;
wd->dev = dev;
dispatcher_add(&vubr->dispatcher, fd, wd, watch_cb);
}
static void
vubr_handle_tx(VuDev *dev, int qidx)
{
VuVirtq *vq = vu_get_queue(dev, qidx);
VubrDev *vubr = container_of(dev, VubrDev, vudev);
int hdrlen = vubr->hdrlen;
VuVirtqElement *elem = NULL;
assert(qidx % 2);
for (;;) {
ssize_t ret;
unsigned int out_num;
struct iovec sg[VIRTQUEUE_MAX_SIZE], *out_sg;
elem = vu_queue_pop(dev, vq, sizeof(VuVirtqElement));
if (!elem) {
break;
}
out_num = elem->out_num;
out_sg = elem->out_sg;
if (out_num < 1) {
fprintf(stderr, "virtio-net header not in first element\n");
break;
}
if (VHOST_USER_BRIDGE_DEBUG) {
iov_hexdump(out_sg, out_num, stderr, "TX:", 1024);
}
if (hdrlen) {
unsigned sg_num = iov_copy(sg, ARRAY_SIZE(sg),
out_sg, out_num,
hdrlen, -1);
out_num = sg_num;
out_sg = sg;
}
struct msghdr msg = {
.msg_name = (struct sockaddr *) &vubr->backend_udp_dest,
.msg_namelen = sizeof(struct sockaddr_in),
.msg_iov = out_sg,
.msg_iovlen = out_num,
};
do {
ret = sendmsg(vubr->backend_udp_sock, &msg, 0);
} while (ret == -1 && (errno == EAGAIN || errno == EINTR));
if (ret == -1) {
vubr_die("sendmsg()");
}
vu_queue_push(dev, vq, elem, 0);
vu_queue_notify(dev, vq);
free(elem);
elem = NULL;
}
free(elem);
}
/* this function reverse the effect of iov_discard_front() it must be
* called with 'front' being the original struct iovec and 'bytes'
* being the number of bytes you shaved off
*/
static void
iov_restore_front(struct iovec *front, struct iovec *iov, size_t bytes)
{
struct iovec *cur;
for (cur = front; cur != iov; cur++) {
assert(bytes >= cur->iov_len);
bytes -= cur->iov_len;
}
cur->iov_base -= bytes;
cur->iov_len += bytes;
}
static void
iov_truncate(struct iovec *iov, unsigned iovc, size_t bytes)
{
unsigned i;
for (i = 0; i < iovc; i++, iov++) {
if (bytes < iov->iov_len) {
iov->iov_len = bytes;
return;
}
bytes -= iov->iov_len;
}
assert(!"couldn't truncate iov");
}
