Implement virtIO net device

Co-authored-by: Alex Brown <[email protected]>
Signed-off-by: Jingyao Zhou <[email protected]>

docs/MANUAL.md

@@ -207,6 +207,7 @@ and implements the following devices:
 * Console
 * Block
 * Sound
+* Network
 
 These devices are implemented using MMIO, we do not use any PCI devices at this stage.
 
@@ -261,6 +262,18 @@ There are no feature bits to implement. The legacy interface is not supported.
 
 The sound device communicates with a hardware sound device via a sDDF sound virtualiser.
 
+### Network
+
+The network device makes use of the 'net' device class in sDDF.
+
+The device supports `VIRTIO_NET_F_MAC`. No other features are available.
+
+The legacy interface is not supported.
+
+The network device communicates with a hardware network card via a pair of sDDF RX and TX
+net virtualisers. In the future, this communication may be done through
+intermediary components such as a virtual network switch (VSwitch).
+
 # Adding platform support
 
 This section will describe how to add support for a new platform to the `simple`

include/libvmm/virtio/net.h

@@ -0,0 +1,240 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+   Copyright Linux */
+
+/* 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. */
+
+#pragma once
+
+#include <stdint.h>
+#include <sddf/network/queue.h>
+#include <libvmm/virtio/mmio.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_MAC                5   /* Host has given MAC address. */
+#define VIRTIO_NET_F_GSO                6   /* Host handles pkts w/ any GSO type */
+#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_S_LINK_UP            1   /* Link is up */
+#define VIRTIO_NET_S_ANNOUNCE           2   /* Announcement is needed */
+
+#define VIRTIO_NET_CONFIG_MAC_SZ        6
+
+struct virtio_net_config {
+    /* The config defining mac address (if VIRTIO_NET_F_MAC) */
+    uint8_t mac[VIRTIO_NET_CONFIG_MAC_SZ];
+    /* See VIRTIO_NET_F_STATUS and VIRTIO_NET_S_* above */
+    // uint16_t 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
+     */
+    // uint16_t max_virtqueue_pairs;
+} __attribute__((packed));
+
+/* This header comes first in the scatter-gather list.
+ * 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 {
+#define VIRTIO_NET_HDR_F_NEEDS_CSUM     1   // Use csum_start, csum_offset
+#define VIRTIO_NET_HDR_F_DATA_VALID     2   // Csum is valid
+    uint8_t 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
+    uint8_t gso_type;
+    uint16_t hdr_len;       /* Ethernet + IP + tcp/udp hdrs */
+    uint16_t gso_size;      /* Bytes to append to hdr_len per frame */
+    uint16_t csum_start;    /* Position to start checksumming from */
+    uint16_t csum_offset;   /* Offset after that to place checksum */
+};
+
+/* The legacy driver only presented num_buffers in the struct virtio_net_hdr
+ * when VIRTIO_NET_F_MRG_RXBUF was negotiated; without that feature the
+ * structure was 2 bytes shorter. So please use this one if you're not dealing
+ * with a legacy driver
+ */
+struct virtio_net_hdr_mrg_rxbuf {
+    struct virtio_net_hdr hdr;
+    uint16_t num_buffers;   /* Number of merged rx buffers */
+};
+
+/*
+ * 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 {
+    uint8_t class;
+    uint8_t cmd;
+} __attribute__((packed));
+
+typedef uint8_t 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 {
+    uint32_t entries;
+    uint8_t macs[][6];
+} __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
+ *
+ * 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 {
+    uint16_t virtqueue_pairs;
+};
+
+#define VIRTIO_NET_CTRL_MQ   4
+#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
+
+#define VIRTIO_NET_RX_VIRTQ     0
+#define VIRTIO_NET_TX_VIRTQ     1
+#define VIRTIO_NET_NUM_VIRTQ    2
+
+struct virtio_net_device {
+    struct virtio_device virtio_device;
+
+    struct virtio_net_config config;
+    struct virtio_queue_handler vqs[VIRTIO_NET_NUM_VIRTQ];
+
+    net_queue_handle_t rx;
+    net_queue_handle_t tx;
+    void *rx_data;
+    void *tx_data;
+    microkit_channel tx_ch;
+    microkit_channel rx_ch;
+};
+
+bool virtio_mmio_net_init(struct virtio_net_device *dev,
+                          uint8_t mac[VIRTIO_NET_CONFIG_MAC_SZ],
+                          uintptr_t region_base,
+                          uintptr_t region_size,
+                          size_t virq,
+                          net_queue_handle_t *rx,
+                          net_queue_handle_t *tx,
+                          uintptr_t rx_data,
+                          uintptr_t tx_data,
+                          microkit_channel rx_ch,
+                          microkit_channel tx_ch);
+
+bool virtio_net_handle_rx(struct virtio_net_device *dev);

include/libvmm/virtio/virtio.h

@@ -3,6 +3,7 @@
 #include <libvmm/virtio/mmio.h>
 #include <libvmm/virtio/block.h>
 #include <libvmm/virtio/console.h>
+#include <libvmm/virtio/net.h>
 #include <libvmm/virtio/sound.h>
 
 /*