[PATCH] net: add virtio network driver

Ahmad Fatoum ahmad at a3f.at
Mon Sep 13 01:30:47 PDT 2021


This gives virtio-enabled boards an easy route to network connectivity:

	qemu-system-aarch64 -M virt  -serial mon:stdio -trace file=/dev/null \
	-kernel images/barebox-dt-2nd.img -cpu cortex-a57 -nographic \
	-device virtio-net-device,netdev=network0 -netdev tap,id=network0,ifname=tap0

The tap0 interface created by QEMU can then be bridged/listened on.

Signed-off-by: Ahmad Fatoum <ahmad at a3f.at>
---
 Documentation/user/virtio.rst   |   2 +-
 drivers/net/Kconfig             |   7 +
 drivers/net/Makefile            |   1 +
 drivers/net/virtio.c            | 236 +++++++++++++++++++++
 include/linux/virtio_config.h   |   7 +-
 include/uapi/linux/virtio_net.h | 358 ++++++++++++++++++++++++++++++++
 6 files changed, 608 insertions(+), 3 deletions(-)
 create mode 100644 drivers/net/virtio.c
 create mode 100644 include/uapi/linux/virtio_net.h

diff --git a/Documentation/user/virtio.rst b/Documentation/user/virtio.rst
index dde47d5f82b1..d944fa4821b1 100644
--- a/Documentation/user/virtio.rst
+++ b/Documentation/user/virtio.rst
@@ -35,7 +35,7 @@ queues configuration and buffer transfers are nearly identical. Both MMIO
 and non-legacy PCI are supported in barebox.
 
 The VirtIO spec defines a lots of VirtIO device types, however at present only
-block, console, input and RNG devices are supported.
+block, network, console, input and RNG devices are supported.
 
 Build Instructions
 ------------------
diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig
index 397164f3f175..4947296f278a 100644
--- a/drivers/net/Kconfig
+++ b/drivers/net/Kconfig
@@ -258,6 +258,13 @@ config DRIVER_NET_EFI_SNP
 	bool "EFI SNP ethernet driver"
 	depends on EFI_BOOTUP
 
+config DRIVER_NET_VIRTIO
+	bool "virtio net driver"
+	depends on VIRTIO
+	help
+	  This is the virtual net driver for virtio. It can be used with
+	  QEMU based targets.
+
 config DRIVER_NET_AG71XX
 	bool "Atheros AG71xx ethernet driver"
 	depends on MACH_MIPS_ATH79
diff --git a/drivers/net/Makefile b/drivers/net/Makefile
index b1aa9571fc72..1921d0d9f91c 100644
--- a/drivers/net/Makefile
+++ b/drivers/net/Makefile
@@ -36,4 +36,5 @@ obj-$(CONFIG_DRIVER_NET_SMC91111)	+= smc91111.o
 obj-$(CONFIG_DRIVER_NET_TAP)		+= tap.o
 obj-$(CONFIG_DRIVER_NET_TSE)		+= altera_tse.o
 obj-$(CONFIG_DRIVER_NET_EFI_SNP)	+= efi-snp.o
+obj-$(CONFIG_DRIVER_NET_VIRTIO)		+= virtio.o
 obj-$(CONFIG_DRIVER_NET_AG71XX)		+= ag71xx.o
diff --git a/drivers/net/virtio.c b/drivers/net/virtio.c
new file mode 100644
index 000000000000..275588e15c50
--- /dev/null
+++ b/drivers/net/virtio.c
@@ -0,0 +1,236 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018, Tuomas Tynkkynen <tuomas.tynkkynen at iki.fi>
+ * Copyright (C) 2018, Bin Meng <bmeng.cn at gmail.com>
+ */
+
+#include <common.h>
+#include <driver.h>
+#include <malloc.h>
+#include <net.h>
+#include <init.h>
+#include <net.h>
+#include <linux/virtio.h>
+#include <linux/virtio_ring.h>
+#include <uapi/linux/virtio_net.h>
+
+/* Amount of buffers to keep in the RX virtqueue */
+#define VIRTIO_NET_NUM_RX_BUFS	32
+
+/*
+ * This value comes from the VirtIO spec: 1500 for maximum packet size,
+ * 14 for the Ethernet header, 12 for virtio_net_hdr. In total 1526 bytes.
+ */
+#define VIRTIO_NET_RX_BUF_SIZE	1526
+
+struct virtio_net_priv {
+	union {
+		struct virtqueue *vqs[2];
+		struct {
+			struct virtqueue *rx_vq;
+			struct virtqueue *tx_vq;
+		};
+	};
+
+	char rx_buff[VIRTIO_NET_NUM_RX_BUFS][VIRTIO_NET_RX_BUF_SIZE];
+	bool rx_running;
+	int net_hdr_len;
+	struct eth_device edev;
+	struct virtio_device *vdev;
+};
+
+static inline struct virtio_net_priv *to_priv(struct eth_device *edev)
+{
+	return container_of(edev, struct virtio_net_priv, edev);
+}
+
+static int virtio_net_start(struct eth_device *edev)
+{
+	struct virtio_net_priv *priv = to_priv(edev);
+	struct virtio_sg sg;
+	struct virtio_sg *sgs[] = { &sg };
+	int i;
+
+	if (!priv->rx_running) {
+		/* receive buffer length is always 1526 */
+		sg.length = VIRTIO_NET_RX_BUF_SIZE;
+
+		/* setup the receive buffer address */
+		for (i = 0; i < VIRTIO_NET_NUM_RX_BUFS; i++) {
+			sg.addr = priv->rx_buff[i];
+			virtqueue_add(priv->rx_vq, sgs, 0, 1);
+		}
+
+		virtqueue_kick(priv->rx_vq);
+
+		/* setup the receive queue only once */
+		priv->rx_running = true;
+	}
+
+	return 0;
+}
+
+static int virtio_net_send(struct eth_device *edev, void *packet, int length)
+{
+	struct virtio_net_priv *priv = to_priv(edev);
+	struct virtio_net_hdr_v1 hdr_v1;
+	struct virtio_net_hdr hdr;
+	struct virtio_sg hdr_sg;
+	struct virtio_sg data_sg = { packet, length };
+	struct virtio_sg *sgs[] = { &hdr_sg, &data_sg };
+	int ret;
+
+	if (priv->net_hdr_len == sizeof(struct virtio_net_hdr))
+		hdr_sg.addr = &hdr;
+	else
+		hdr_sg.addr = &hdr_v1;
+
+	hdr_sg.length = priv->net_hdr_len;
+	memset(hdr_sg.addr, 0, priv->net_hdr_len);
+
+	ret = virtqueue_add(priv->tx_vq, sgs, 2, 0);
+	if (ret)
+		return ret;
+
+	virtqueue_kick(priv->tx_vq);
+
+	while (1) {
+		if (virtqueue_get_buf(priv->tx_vq, NULL))
+			break;
+	}
+
+	return 0;
+}
+
+static int virtio_net_recv(struct eth_device *edev)
+{
+	struct virtio_net_priv *priv = to_priv(edev);
+	struct virtio_sg sg;
+	struct virtio_sg *sgs[] = { &sg };
+	unsigned int len;
+	void *buf;
+
+	sg.addr = virtqueue_get_buf(priv->rx_vq, &len);
+	if (!sg.addr)
+		return -EAGAIN;
+
+	sg.length = VIRTIO_NET_RX_BUF_SIZE;
+
+	buf = sg.addr + priv->net_hdr_len;
+	len -= priv->net_hdr_len;
+
+	net_receive(edev, buf, len);
+
+	/* Put the buffer back to the rx ring */
+	virtqueue_add(priv->rx_vq, sgs, 0, 1);
+
+	return 0;
+}
+
+static void virtio_net_stop(struct eth_device *dev)
+{
+	/*
+	 * There is no way to stop the queue from running, unless we issue
+	 * a reset to the virtio device, and re-do the queue initialization
+	 * from the beginning.
+	 */
+}
+
+static int virtio_net_write_hwaddr(struct eth_device *edev, const unsigned char *adr)
+{
+	struct virtio_net_priv *priv = to_priv(edev);
+	int i;
+
+	/*
+	 * v1.0 compliant device's MAC address is set through control channel,
+	 * which we don't support for now.
+	 */
+	if (virtio_has_feature(priv->vdev, VIRTIO_F_VERSION_1))
+		return -ENOSYS;
+
+	for (i = 0; i < 6; i++)
+		virtio_cwrite8(priv->vdev, offsetof(struct virtio_net_config, mac) + i, adr[i]);
+
+	return 0;
+}
+
+static int virtio_net_read_rom_hwaddr(struct eth_device *edev, unsigned char *adr)
+{
+	struct virtio_net_priv *priv = to_priv(edev);
+
+	virtio_cread_bytes(priv->vdev, offsetof(struct virtio_net_config, mac), adr, 6);
+
+	return 0;
+}
+
+static int virtio_net_probe(struct virtio_device *vdev)
+{
+	struct virtio_net_priv *priv;
+	struct eth_device *edev;
+	int ret;
+
+	priv = xzalloc(sizeof(*priv));
+
+	/*
+	 * For v1.0 compliant device, it always assumes the member
+	 * 'num_buffers' exists in the struct virtio_net_hdr while
+	 * the legacy driver only presented 'num_buffers' when
+	 * VIRTIO_NET_F_MRG_RXBUF was negotiated. Without that feature
+	 * the structure was 2 bytes shorter.
+	 */
+	if (virtio_has_feature(vdev, VIRTIO_F_VERSION_1))
+		priv->net_hdr_len = sizeof(struct virtio_net_hdr_v1);
+	else
+		priv->net_hdr_len = sizeof(struct virtio_net_hdr);
+
+	ret = virtio_find_vqs(vdev, 2, priv->vqs);
+	if (ret < 0)
+		return ret;
+
+	priv->vdev = vdev;
+
+	edev = &priv->edev;
+	edev->priv = priv;
+	edev->parent = &vdev->dev;
+
+	edev->open = virtio_net_start;
+	edev->send = virtio_net_send;
+	edev->recv = virtio_net_recv;
+	edev->halt = virtio_net_stop;
+	edev->get_ethaddr = virtio_net_read_rom_hwaddr;
+	edev->set_ethaddr = virtio_net_write_hwaddr;
+
+	return eth_register(edev);
+}
+
+static void virtio_net_remove(struct virtio_device *vdev)
+{
+	vdev->config->reset(vdev);
+	vdev->config->del_vqs(vdev);
+}
+
+/*
+ * For simplicity, the driver only negotiates the VIRTIO_NET_F_MAC feature.
+ * For the VIRTIO_NET_F_STATUS feature, we don't negotiate it, hence per spec
+ * we should assume the link is always active.
+ */
+static const u32 features[] = {
+	VIRTIO_NET_F_MAC
+};
+
+static const struct virtio_device_id id_table[] = {
+        { VIRTIO_ID_NET, VIRTIO_DEV_ANY_ID },
+        { 0 },
+};
+
+static struct virtio_driver virtio_net = {
+        .driver.name	= "virtio_net",
+        .id_table	= id_table,
+        .probe		= virtio_net_probe,
+	.remove		= virtio_net_remove,
+	.feature_table			= features,
+	.feature_table_size		= ARRAY_SIZE(features),
+	.feature_table_legacy		= features,
+	.feature_table_size_legacy	= ARRAY_SIZE(features),
+};
+device_virtio_driver(virtio_net);
diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 8160f0952f13..6bb1f768b636 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -232,8 +232,11 @@ static inline int virtio_get_config(struct virtio_device *vdev, unsigned int off
  * @len:	the length of the buffer
  * @return 0 if OK, -ve on error
  */
-int virtio_set_config(struct virtio_device *vdev, unsigned int offset,
-		      void *buf, unsigned int len);
+static inline int virtio_set_config(struct virtio_device *vdev, unsigned int offset,
+		      void *buf, unsigned int len)
+{
+	return vdev->config->set_config(vdev, offset, buf, len);
+}
 
 /**
  * virtio_find_vqs() - find virtqueues and instantiate them
diff --git a/include/uapi/linux/virtio_net.h b/include/uapi/linux/virtio_net.h
new file mode 100644
index 000000000000..c1896b1cfc65
--- /dev/null
+++ b/include/uapi/linux/virtio_net.h
@@ -0,0 +1,358 @@
+#ifndef _UAPI_LINUX_VIRTIO_NET_H
+#define _UAPI_LINUX_VIRTIO_NET_H
+/* This header is BSD licensed so anyone can use the definitions to implement
+ * compatible drivers/servers.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE. */
+#include <linux/types.h>
+#include <linux/virtio_ids.h>
+#include <linux/virtio_config.h>
+#include <linux/virtio_types.h>
+#include <net.h>
+
+/* The feature bitmap for virtio net */
+#define VIRTIO_NET_F_CSUM	0	/* Host handles pkts w/ partial csum */
+#define VIRTIO_NET_F_GUEST_CSUM	1	/* Guest handles pkts w/ partial csum */
+#define VIRTIO_NET_F_CTRL_GUEST_OFFLOADS 2 /* Dynamic offload configuration. */
+#define VIRTIO_NET_F_MTU	3	/* Initial MTU advice */
+#define VIRTIO_NET_F_MAC	5	/* Host has given MAC address. */
+#define VIRTIO_NET_F_GUEST_TSO4	7	/* Guest can handle TSOv4 in. */
+#define VIRTIO_NET_F_GUEST_TSO6	8	/* Guest can handle TSOv6 in. */
+#define VIRTIO_NET_F_GUEST_ECN	9	/* Guest can handle TSO[6] w/ ECN in. */
+#define VIRTIO_NET_F_GUEST_UFO	10	/* Guest can handle UFO in. */
+#define VIRTIO_NET_F_HOST_TSO4	11	/* Host can handle TSOv4 in. */
+#define VIRTIO_NET_F_HOST_TSO6	12	/* Host can handle TSOv6 in. */
+#define VIRTIO_NET_F_HOST_ECN	13	/* Host can handle TSO[6] w/ ECN in. */
+#define VIRTIO_NET_F_HOST_UFO	14	/* Host can handle UFO in. */
+#define VIRTIO_NET_F_MRG_RXBUF	15	/* Host can merge receive buffers. */
+#define VIRTIO_NET_F_STATUS	16	/* virtio_net_config.status available */
+#define VIRTIO_NET_F_CTRL_VQ	17	/* Control channel available */
+#define VIRTIO_NET_F_CTRL_RX	18	/* Control channel RX mode support */
+#define VIRTIO_NET_F_CTRL_VLAN	19	/* Control channel VLAN filtering */
+#define VIRTIO_NET_F_CTRL_RX_EXTRA 20	/* Extra RX mode control support */
+#define VIRTIO_NET_F_GUEST_ANNOUNCE 21	/* Guest can announce device on the
+					 * network */
+#define VIRTIO_NET_F_MQ	22	/* Device supports Receive Flow
+					 * Steering */
+#define VIRTIO_NET_F_CTRL_MAC_ADDR 23	/* Set MAC address */
+
+#define VIRTIO_NET_F_HASH_REPORT  57	/* Supports hash report */
+#define VIRTIO_NET_F_RSS	  60	/* Supports RSS RX steering */
+#define VIRTIO_NET_F_RSC_EXT	  61	/* extended coalescing info */
+#define VIRTIO_NET_F_STANDBY	  62	/* Act as standby for another device
+					 * with the same MAC.
+					 */
+#define VIRTIO_NET_F_SPEED_DUPLEX 63	/* Device set linkspeed and duplex */
+
+#ifndef VIRTIO_NET_NO_LEGACY
+#define VIRTIO_NET_F_GSO	6	/* Host handles pkts w/ any GSO type */
+#endif /* VIRTIO_NET_NO_LEGACY */
+
+#define VIRTIO_NET_S_LINK_UP	1	/* Link is up */
+#define VIRTIO_NET_S_ANNOUNCE	2	/* Announcement is needed */
+
+/* supported/enabled hash types */
+#define VIRTIO_NET_RSS_HASH_TYPE_IPv4          (1 << 0)
+#define VIRTIO_NET_RSS_HASH_TYPE_TCPv4         (1 << 1)
+#define VIRTIO_NET_RSS_HASH_TYPE_UDPv4         (1 << 2)
+#define VIRTIO_NET_RSS_HASH_TYPE_IPv6          (1 << 3)
+#define VIRTIO_NET_RSS_HASH_TYPE_TCPv6         (1 << 4)
+#define VIRTIO_NET_RSS_HASH_TYPE_UDPv6         (1 << 5)
+#define VIRTIO_NET_RSS_HASH_TYPE_IP_EX         (1 << 6)
+#define VIRTIO_NET_RSS_HASH_TYPE_TCP_EX        (1 << 7)
+#define VIRTIO_NET_RSS_HASH_TYPE_UDP_EX        (1 << 8)
+
+struct virtio_net_config {
+	/* The config defining mac address (if VIRTIO_NET_F_MAC) */
+	__u8 mac[ETH_ALEN];
+	/* See VIRTIO_NET_F_STATUS and VIRTIO_NET_S_* above */
+	__virtio16 status;
+	/* Maximum number of each of transmit and receive queues;
+	 * see VIRTIO_NET_F_MQ and VIRTIO_NET_CTRL_MQ.
+	 * Legal values are between 1 and 0x8000
+	 */
+	__virtio16 max_virtqueue_pairs;
+	/* Default maximum transmit unit advice */
+	__virtio16 mtu;
+	/*
+	 * speed, in units of 1Mb. All values 0 to INT_MAX are legal.
+	 * Any other value stands for unknown.
+	 */
+	__le32 speed;
+	/*
+	 * 0x00 - half duplex
+	 * 0x01 - full duplex
+	 * Any other value stands for unknown.
+	 */
+	__u8 duplex;
+	/* maximum size of RSS key */
+	__u8 rss_max_key_size;
+	/* maximum number of indirection table entries */
+	__le16 rss_max_indirection_table_length;
+	/* bitmask of supported VIRTIO_NET_RSS_HASH_ types */
+	__le32 supported_hash_types;
+} __attribute__((packed));
+
+/*
+ * This header comes first in the scatter-gather list.  If you don't
+ * specify GSO or CSUM features, you can simply ignore the header.
+ *
+ * This is bitwise-equivalent to the legacy struct virtio_net_hdr_mrg_rxbuf,
+ * only flattened.
+ */
+struct virtio_net_hdr_v1 {
+#define VIRTIO_NET_HDR_F_NEEDS_CSUM	1	/* Use csum_start, csum_offset */
+#define VIRTIO_NET_HDR_F_DATA_VALID	2	/* Csum is valid */
+#define VIRTIO_NET_HDR_F_RSC_INFO	4	/* rsc info in csum_ fields */
+	__u8 flags;
+#define VIRTIO_NET_HDR_GSO_NONE		0	/* Not a GSO frame */
+#define VIRTIO_NET_HDR_GSO_TCPV4	1	/* GSO frame, IPv4 TCP (TSO) */
+#define VIRTIO_NET_HDR_GSO_UDP		3	/* GSO frame, IPv4 UDP (UFO) */
+#define VIRTIO_NET_HDR_GSO_TCPV6	4	/* GSO frame, IPv6 TCP */
+#define VIRTIO_NET_HDR_GSO_ECN		0x80	/* TCP has ECN set */
+	__u8 gso_type;
+	__virtio16 hdr_len;	/* Ethernet + IP + tcp/udp hdrs */
+	__virtio16 gso_size;	/* Bytes to append to hdr_len per frame */
+	union {
+		struct {
+			__virtio16 csum_start;
+			__virtio16 csum_offset;
+		};
+		/* Checksum calculation */
+		struct {
+			/* Position to start checksumming from */
+			__virtio16 start;
+			/* Offset after that to place checksum */
+			__virtio16 offset;
+		} csum;
+		/* Receive Segment Coalescing */
+		struct {
+			/* Number of coalesced segments */
+			__le16 segments;
+			/* Number of duplicated acks */
+			__le16 dup_acks;
+		} rsc;
+	};
+	__virtio16 num_buffers;	/* Number of merged rx buffers */
+};
+
+struct virtio_net_hdr_v1_hash {
+	struct virtio_net_hdr_v1 hdr;
+	__le32 hash_value;
+#define VIRTIO_NET_HASH_REPORT_NONE            0
+#define VIRTIO_NET_HASH_REPORT_IPv4            1
+#define VIRTIO_NET_HASH_REPORT_TCPv4           2
+#define VIRTIO_NET_HASH_REPORT_UDPv4           3
+#define VIRTIO_NET_HASH_REPORT_IPv6            4
+#define VIRTIO_NET_HASH_REPORT_TCPv6           5
+#define VIRTIO_NET_HASH_REPORT_UDPv6           6
+#define VIRTIO_NET_HASH_REPORT_IPv6_EX         7
+#define VIRTIO_NET_HASH_REPORT_TCPv6_EX        8
+#define VIRTIO_NET_HASH_REPORT_UDPv6_EX        9
+	__le16 hash_report;
+	__le16 padding;
+};
+
+#ifndef VIRTIO_NET_NO_LEGACY
+/* This header comes first in the scatter-gather list.
+ * For legacy virtio, if VIRTIO_F_ANY_LAYOUT is not negotiated, it must
+ * be the first element of the scatter-gather list.  If you don't
+ * specify GSO or CSUM features, you can simply ignore the header. */
+struct virtio_net_hdr {
+	/* See VIRTIO_NET_HDR_F_* */
+	__u8 flags;
+	/* See VIRTIO_NET_HDR_GSO_* */
+	__u8 gso_type;
+	__virtio16 hdr_len;		/* Ethernet + IP + tcp/udp hdrs */
+	__virtio16 gso_size;		/* Bytes to append to hdr_len per frame */
+	__virtio16 csum_start;	/* Position to start checksumming from */
+	__virtio16 csum_offset;	/* Offset after that to place checksum */
+};
+
+/* This is the version of the header to use when the MRG_RXBUF
+ * feature has been negotiated. */
+struct virtio_net_hdr_mrg_rxbuf {
+	struct virtio_net_hdr hdr;
+	__virtio16 num_buffers;	/* Number of merged rx buffers */
+};
+#endif /* ...VIRTIO_NET_NO_LEGACY */
+
+/*
+ * Control virtqueue data structures
+ *
+ * The control virtqueue expects a header in the first sg entry
+ * and an ack/status response in the last entry.  Data for the
+ * command goes in between.
+ */
+struct virtio_net_ctrl_hdr {
+	__u8 class;
+	__u8 cmd;
+} __attribute__((packed));
+
+typedef __u8 virtio_net_ctrl_ack;
+
+#define VIRTIO_NET_OK     0
+#define VIRTIO_NET_ERR    1
+
+/*
+ * Control the RX mode, ie. promisucous, allmulti, etc...
+ * All commands require an "out" sg entry containing a 1 byte
+ * state value, zero = disable, non-zero = enable.  Commands
+ * 0 and 1 are supported with the VIRTIO_NET_F_CTRL_RX feature.
+ * Commands 2-5 are added with VIRTIO_NET_F_CTRL_RX_EXTRA.
+ */
+#define VIRTIO_NET_CTRL_RX    0
+ #define VIRTIO_NET_CTRL_RX_PROMISC      0
+ #define VIRTIO_NET_CTRL_RX_ALLMULTI     1
+ #define VIRTIO_NET_CTRL_RX_ALLUNI       2
+ #define VIRTIO_NET_CTRL_RX_NOMULTI      3
+ #define VIRTIO_NET_CTRL_RX_NOUNI        4
+ #define VIRTIO_NET_CTRL_RX_NOBCAST      5
+
+/*
+ * Control the MAC
+ *
+ * The MAC filter table is managed by the hypervisor, the guest should
+ * assume the size is infinite.  Filtering should be considered
+ * non-perfect, ie. based on hypervisor resources, the guest may
+ * received packets from sources not specified in the filter list.
+ *
+ * In addition to the class/cmd header, the TABLE_SET command requires
+ * two out scatterlists.  Each contains a 4 byte count of entries followed
+ * by a concatenated byte stream of the ETH_ALEN MAC addresses.  The
+ * first sg list contains unicast addresses, the second is for multicast.
+ * This functionality is present if the VIRTIO_NET_F_CTRL_RX feature
+ * is available.
+ *
+ * The ADDR_SET command requests one out scatterlist, it contains a
+ * 6 bytes MAC address. This functionality is present if the
+ * VIRTIO_NET_F_CTRL_MAC_ADDR feature is available.
+ */
+struct virtio_net_ctrl_mac {
+	__virtio32 entries;
+	__u8 macs[][ETH_ALEN];
+} __attribute__((packed));
+
+#define VIRTIO_NET_CTRL_MAC    1
+ #define VIRTIO_NET_CTRL_MAC_TABLE_SET        0
+ #define VIRTIO_NET_CTRL_MAC_ADDR_SET         1
+
+/*
+ * Control VLAN filtering
+ *
+ * The VLAN filter table is controlled via a simple ADD/DEL interface.
+ * VLAN IDs not added may be filterd by the hypervisor.  Del is the
+ * opposite of add.  Both commands expect an out entry containing a 2
+ * byte VLAN ID.  VLAN filterting is available with the
+ * VIRTIO_NET_F_CTRL_VLAN feature bit.
+ */
+#define VIRTIO_NET_CTRL_VLAN       2
+ #define VIRTIO_NET_CTRL_VLAN_ADD             0
+ #define VIRTIO_NET_CTRL_VLAN_DEL             1
+
+/*
+ * Control link announce acknowledgement
+ *
+ * The command VIRTIO_NET_CTRL_ANNOUNCE_ACK is used to indicate that
+ * driver has recevied the notification; device would clear the
+ * VIRTIO_NET_S_ANNOUNCE bit in the status field after it receives
+ * this command.
+ */
+#define VIRTIO_NET_CTRL_ANNOUNCE       3
+ #define VIRTIO_NET_CTRL_ANNOUNCE_ACK         0
+
+/*
+ * Control Receive Flow Steering
+ */
+#define VIRTIO_NET_CTRL_MQ   4
+/*
+ * The command VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET
+ * enables Receive Flow Steering, specifying the number of the transmit and
+ * receive queues that will be used. After the command is consumed and acked by
+ * the device, the device will not steer new packets on receive virtqueues
+ * other than specified nor read from transmit virtqueues other than specified.
+ * Accordingly, driver should not transmit new packets  on virtqueues other than
+ * specified.
+ */
+struct virtio_net_ctrl_mq {
+	__virtio16 virtqueue_pairs;
+};
+
+ #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET        0
+ #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN        1
+ #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX        0x8000
+
+/*
+ * The command VIRTIO_NET_CTRL_MQ_RSS_CONFIG has the same effect as
+ * VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET does and additionally configures
+ * the receive steering to use a hash calculated for incoming packet
+ * to decide on receive virtqueue to place the packet. The command
+ * also provides parameters to calculate a hash and receive virtqueue.
+ */
+struct virtio_net_rss_config {
+	__le32 hash_types;
+	__le16 indirection_table_mask;
+	__le16 unclassified_queue;
+	__le16 indirection_table[1/* + indirection_table_mask */];
+	__le16 max_tx_vq;
+	__u8 hash_key_length;
+	__u8 hash_key_data[/* hash_key_length */];
+};
+
+ #define VIRTIO_NET_CTRL_MQ_RSS_CONFIG          1
+
+/*
+ * The command VIRTIO_NET_CTRL_MQ_HASH_CONFIG requests the device
+ * to include in the virtio header of the packet the value of the
+ * calculated hash and the report type of hash. It also provides
+ * parameters for hash calculation. The command requires feature
+ * VIRTIO_NET_F_HASH_REPORT to be negotiated to extend the
+ * layout of virtio header as defined in virtio_net_hdr_v1_hash.
+ */
+struct virtio_net_hash_config {
+	__le32 hash_types;
+	/* for compatibility with virtio_net_rss_config */
+	__le16 reserved[4];
+	__u8 hash_key_length;
+	__u8 hash_key_data[/* hash_key_length */];
+};
+
+ #define VIRTIO_NET_CTRL_MQ_HASH_CONFIG         2
+
+/*
+ * Control network offloads
+ *
+ * Reconfigures the network offloads that Guest can handle.
+ *
+ * Available with the VIRTIO_NET_F_CTRL_GUEST_OFFLOADS feature bit.
+ *
+ * Command data format matches the feature bit mask exactly.
+ *
+ * See VIRTIO_NET_F_GUEST_* for the list of offloads
+ * that can be enabled/disabled.
+ */
+#define VIRTIO_NET_CTRL_GUEST_OFFLOADS   5
+#define VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET        0
+
+#endif /* _UAPI_LINUX_VIRTIO_NET_H */
-- 
2.33.0




More information about the barebox mailing list