This virtio-net driver contains the recv() and send() functions
that are required by libnet to receive and send packets.
Signed-off-by: Thomas Huth <th...@redhat.com>
---
pc-bios/s390-ccw/Makefile | 2 +-
pc-bios/s390-ccw/virtio-net.c | 125 ++++++++++++++++++++++++++++++++++++++++++
pc-bios/s390-ccw/virtio.c | 16 ++++--
pc-bios/s390-ccw/virtio.h | 11 ++++
4 files changed, 149 insertions(+), 5 deletions(-)
create mode 100644 pc-bios/s390-ccw/virtio-net.c
diff --git a/pc-bios/s390-ccw/Makefile b/pc-bios/s390-ccw/Makefile
index 02b9b08..369bd65 100644
--- a/pc-bios/s390-ccw/Makefile
+++ b/pc-bios/s390-ccw/Makefile
@@ -9,7 +9,7 @@ $(call set-vpath, $(SRC_PATH)/pc-bios/s390-ccw)
.PHONY : all clean build-all libc.a libnet.a
-OBJECTS = start.o main.o bootmap.o sclp.o virtio.o virtio-scsi.o
+OBJECTS = start.o main.o bootmap.o sclp.o virtio.o virtio-scsi.o virtio-net.o
OBJECTS += libc.a sbrk.o
QEMU_CFLAGS := $(filter -W%, $(QEMU_CFLAGS))
QEMU_CFLAGS += -ffreestanding -fno-delete-null-pointer-checks -msoft-float
diff --git a/pc-bios/s390-ccw/virtio-net.c b/pc-bios/s390-ccw/virtio-net.c
new file mode 100644
index 0000000..5c2f439
--- /dev/null
+++ b/pc-bios/s390-ccw/virtio-net.c
@@ -0,0 +1,125 @@
+/*
+ * Virtio-net driver for the s390-ccw firmware
+ *
+ * Copyright 2017 Thomas Huth, Red Hat Inc.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include "libnet/ethernet.h"
+#include "virtio.h"
+
+#define VQ_RX 0 /* Receive queue */
+#define VQ_TX 1 /* Transmit queue */
+
+struct VirtioNetHdr {
+ uint8_t flags;
+ uint8_t gso_type;
+ uint16_t hdr_len;
+ uint16_t gso_size;
+ uint16_t csum_start;
+ uint16_t csum_offset;
+ /*uint16_t num_buffers;*/ /* Only with VIRTIO_NET_F_MRG_RXBUF or VIRTIO1 */
+};
+typedef struct VirtioNetHdr VirtioNetHdr;
+
+static uint16_t rx_last_idx; /* Last index in receive queue "used" ring */
+
+int socket(int domain, int type, int proto, char *mac_addr)
+{
+ VDev *vdev = virtio_get_device();
+ VRing *rxvq = &vdev->vrings[VQ_RX];
+ void *buf;
+ int i;
+
+ memcpy(mac_addr, vdev->config.net.mac, ETH_ALEN);
+
+ for (i = 0; i < 64; i++) {
+ buf = malloc(ETH_MTU_SIZE + sizeof(VirtioNetHdr));
+ IPL_assert(buf != NULL, "Can not allocate memory for receive buffers");
+ vring_send_buf(rxvq, buf, ETH_MTU_SIZE + sizeof(VirtioNetHdr),
+ VRING_DESC_F_WRITE);
+ }
+ vring_notify(rxvq);
+
+ return 0;
+}
+
+int send(int fd, const void *buf, int len, int flags)
+{
+ VirtioNetHdr tx_hdr;
+ VDev *vdev = virtio_get_device();
+ VRing *txvq = &vdev->vrings[VQ_TX];
+
+ /* Set up header - we do not use anything special, so simply clear it */
+ memset(&tx_hdr, 0, sizeof(tx_hdr));
+
+ vring_send_buf(txvq, &tx_hdr, sizeof(tx_hdr), VRING_DESC_F_NEXT);
+ vring_send_buf(txvq, (void *)buf, len, VRING_HIDDEN_IS_CHAIN);
+ while (!vr_poll(txvq)) {
+ yield();
+ }
+ if (drain_irqs(txvq->schid)) {
+ puts("send: drain irqs failed");
+ return -1;
+ }
+
+ return len;
+}
+
+int recv(int fd, void *buf, int maxlen, int flags)
+{
+ VDev *vdev = virtio_get_device();
+ VRing *rxvq = &vdev->vrings[VQ_RX];
+ int len, id;
+ uint8_t *pkt;
+
+ if (rx_last_idx == rxvq->used->idx) {
+ return 0;
+ }
+
+ len = rxvq->used->ring[rx_last_idx % rxvq->num].len - sizeof(VirtioNetHdr);
+ if (len > maxlen) {
+ puts("virtio-net: Receive buffer too small");
+ len = maxlen;
+ }
+ id = rxvq->used->ring[rx_last_idx % rxvq->num].id % rxvq->num;
+ pkt = (uint8_t *)(rxvq->desc[id].addr + sizeof(VirtioNetHdr));
+
+#if 0
+ /* Dump packet */
+ printf("\nbuf %p: len=%i\n", (void*)rxvq->desc[id].addr, len);
+ int i;
+ for (i = 0; i < 64; i++) {
+ printf(" %02x", pkt[i]);
+ if ((i%16)==15)
+ printf("\n");
+ }
+ printf("\n");
+#endif
+
+ /* Copy data to destination buffer */
+ memcpy(buf, pkt, len);
+
+ /* Mark buffer as available to the host again */
+ rxvq->avail->ring[rxvq->avail->idx % rxvq->num] = id;
+ rxvq->avail->idx = rxvq->avail->idx + 1;
+ vring_notify(rxvq);
+
+ /* Move index to next entry */
+ rx_last_idx = rx_last_idx + 1;
+
+ return len;
+}
+
+int close(int fd)
+{
+ return 0;
+}
diff --git a/pc-bios/s390-ccw/virtio.c b/pc-bios/s390-ccw/virtio.c
index 6ee93d5..b5219aa 100644
--- a/pc-bios/s390-ccw/virtio.c
+++ b/pc-bios/s390-ccw/virtio.c
@@ -69,7 +69,7 @@ static long virtio_notify(SubChannelId schid, int vq_idx,
long cookie)
* Virtio functions *
***********************************************/
-static int drain_irqs(SubChannelId schid)
+int drain_irqs(SubChannelId schid)
{
Irb irb = {};
int r = 0;
@@ -148,13 +148,13 @@ static void vring_init(VRing *vr, VqInfo *info)
debug_print_addr("init vr", vr);
}
-static bool vring_notify(VRing *vr)
+bool vring_notify(VRing *vr)
{
vr->cookie = virtio_notify(vr->schid, vr->id, vr->cookie);
return vr->cookie >= 0;
}
-static void vring_send_buf(VRing *vr, void *p, int len, int flags)
+void vring_send_buf(VRing *vr, void *p, int len, int flags)
{
/* For follow-up chains we need to keep the first entry point */
if (!(flags & VRING_HIDDEN_IS_CHAIN)) {
@@ -187,7 +187,7 @@ ulong get_second(void)
return (get_clock() >> 12) / 1000000;
}
-static int vr_poll(VRing *vr)
+int vr_poll(VRing *vr)
{
if (vr->used->idx == vr->used_idx) {
vring_notify(vr);
@@ -495,6 +495,11 @@ static void virtio_setup_ccw(VDev *vdev)
run_ccw(vdev, CCW_CMD_VDEV_RESET, NULL, 0);
switch (vdev->senseid.cu_model) {
+ case VIRTIO_ID_NET:
+ vdev->nr_vqs = 3;
+ vdev->cmd_vr_idx = 0;
+ cfg_size = sizeof(vdev->config.net);
+ break;
case VIRTIO_ID_BLOCK:
vdev->nr_vqs = 1;
vdev->cmd_vr_idx = 0;
@@ -549,6 +554,9 @@ void virtio_setup_device(SubChannelId schid)
virtio_setup_ccw(&vdev);
switch (vdev.senseid.cu_model) {
+ case VIRTIO_ID_NET:
+ sclp_print("Using virtio-net.\n");
+ break;
case VIRTIO_ID_BLOCK:
sclp_print("Using virtio-blk.\n");
if (!virtio_ipl_disk_is_valid()) {
diff --git a/pc-bios/s390-ccw/virtio.h b/pc-bios/s390-ccw/virtio.h
index 1eaf865..b4e0f41 100644
--- a/pc-bios/s390-ccw/virtio.h
+++ b/pc-bios/s390-ccw/virtio.h
@@ -254,6 +254,12 @@ struct ScsiDevice {
};
typedef struct ScsiDevice ScsiDevice;
+struct VirtioNetConfig {
+ uint8_t mac[6];
+ uint16_t status;
+};
+typedef struct VirtioNetConfig VirtioNetConfig;
+
struct VDev {
int nr_vqs;
VRing *vrings;
@@ -266,6 +272,7 @@ struct VDev {
union {
VirtioBlkConfig blk;
VirtioScsiConfig scsi;
+ VirtioNetConfig net;
} config;
ScsiDevice *scsi_device;
bool is_cdrom;
@@ -291,6 +298,10 @@ struct VirtioCmd {
};
typedef struct VirtioCmd VirtioCmd;
+bool vring_notify(VRing *vr);
+int drain_irqs(SubChannelId schid);
+void vring_send_buf(VRing *vr, void *p, int len, int flags);
+int vr_poll(VRing *vr);
int virtio_run(VDev *vdev, int vqid, VirtioCmd *cmd);
#endif /* VIRTIO_H */
--
1.8.3.1
