pc-bios/s390-ccw: Add virtio-net driver code (00dde1e6) · Commits · SUMMER2020 / students / proj-2021291

pc-bios/s390-ccw/netboot.mak

+1 −1

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		SLOF_DIR := $(SRC_PATH)/roms/SLOF

		NETOBJS := start.o sclp.o virtio.o netmain.o libc.a
		NETOBJS := start.o sclp.o virtio.o virtio-net.o netmain.o libc.a

		LIBC_INC := -nostdinc -I$(SLOF_DIR)/lib/libc/include
		LIBNET_INC := -I$(SLOF_DIR)/lib/libnet

pc-bios/s390-ccw/virtio-net.c

0 → 100644

+135 −0

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		/*
		* 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 <stdint.h>
		#include <stdbool.h>
		#include <stdio.h>
		#include <stdlib.h>
		#include <string.h>
		#include <unistd.h>
		#include <sys/socket.h>
		#include <ethernet.h>
		#include "s390-ccw.h"
		#include "virtio.h"

		#ifndef DEBUG_VIRTIO_NET
		#define DEBUG_VIRTIO_NET 0
		#endif

		#define VIRTIO_NET_F_MAC_BIT (1 << 5)

		#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 virtio_net_init(void *mac_addr)
		{
		VDev *vdev = virtio_get_device();
		VRing *rxvq = &vdev->vrings[VQ_RX];
		void *buf;
		int i;

		vdev->guest_features[0] = VIRTIO_NET_F_MAC_BIT;
		virtio_setup_ccw(vdev);

		IPL_assert(vdev->guest_features[0] & VIRTIO_NET_F_MAC_BIT,
		"virtio-net device does not support the MAC address feature");
		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 DEBUG_VIRTIO_NET /* Dump packet */
		int i;
		printf("\nbuf %p: len=%i\n", (void *)rxvq->desc[id].addr, len);
		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;
		}

pc-bios/s390-ccw/virtio.c

+5 −0

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		@@ -266,6 +266,11 @@ 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 = 2;
		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;

pc-bios/s390-ccw/virtio.h

+10 −2

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		@@ -11,8 +11,6 @@
		#ifndef VIRTIO_H
		#define VIRTIO_H

		#include "s390-ccw.h"

		/* Status byte for guest to report progress, and synchronize features. */
		/* We have seen device and processed generic fields (VIRTIO_CONFIG_F_VIRTIO) */
		#define VIRTIO_CONFIG_S_ACKNOWLEDGE 1
		@@ -227,6 +225,13 @@ struct ScsiDevice {
		};
		typedef struct ScsiDevice ScsiDevice;

		struct VirtioNetConfig {
		uint8_t mac[6];
		/* uint16_t status; / / Only with VIRTIO_NET_F_STATUS */
		/* uint16_t max_virtqueue_pairs; / / Only with VIRTIO_NET_F_MQ */
		};
		typedef struct VirtioNetConfig VirtioNetConfig;

		struct VDev {
		int nr_vqs;
		VRing *vrings;
		@@ -239,6 +244,7 @@ struct VDev {
		union {
		VirtioBlkConfig blk;
		VirtioScsiConfig scsi;
		VirtioNetConfig net;
		} config;
		ScsiDevice *scsi_device;
		bool is_cdrom;
		@@ -273,4 +279,6 @@ int vring_wait_reply(void);
		int virtio_run(VDev vdev, int vqid, VirtioCmd cmd);
		void virtio_setup_ccw(VDev *vdev);

		int virtio_net_init(void *mac_addr);

		#endif /* VIRTIO_H */