Add vhost-user support for the virtio-can device

Enables support to probe, handle and connect virtio-can device
with vhost-user-can via the virtio-loopback-adapter

Depends: 29398
Bug-AGL: SPEC-4834
Change-Id: I31e328aee25b101f51911eab6fd15dc3dd78c771
Signed-off-by: Angelos Mouzakitis <a.mouzakitis@virtualopensystems.com>

1 files changed, 322 insertions, 0 deletions

diff --git a/vhost_user_can.c b/vhost_user_can.c
new file mode 100644
index 0000000..8a1b1ae
--- /dev/null
+++ b/vhost_user_can.c
@@ -0,0 +1,322 @@
+/*
+ * Virtio CAN Device
+ *
+ * Based on virtio_can.h of OpenSynergy's virtio-can RFC
+ * https://github.com/OpenSynergy/qemu/tree/virtio-can-spec-rfc-v3
+ *
+ * Copyright (C) 2021-2023 OpenSynergy GmbH
+ * Copyright (c) 2023 Virtual Open Systems SAS.
+ *
+ * This program 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; version 2.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+#include <stdbool.h>
+#include <sys/param.h>
+
+/* Project header files */
+#include "vhost_user_can.h"
+
+#ifdef DEBUG
+#define DBG(...) printf("vhost-user-can: " __VA_ARGS__)
+#else
+#define DBG(...)
+#endif /* DEBUG */
+
+/***************************** vhost-user-can ******************************/
+
+static const int user_feature_bits[] = {
+    VIRTIO_F_VERSION_1,
+    VIRTIO_RING_F_INDIRECT_DESC,
+    VIRTIO_RING_F_EVENT_IDX,
+    VIRTIO_F_RING_RESET,
+    VIRTIO_F_NOTIFY_ON_EMPTY,
+    VHOST_INVALID_FEATURE_BIT
+};
+
+static void vhost_user_can_get_config(VirtIODevice *vdev, uint8_t *config)
+{
+    VHostUserCan *can = vdev->vhucan;
+
+    DBG("vhost_user_can_get_config: Not yet implemented!\n");
+
+    /*
+     * TODO : Add this check depend on 'busoff' value
+     * if (vcan->busoff) {
+     *     config->status = cpu_to_le32(VIRTIO_CAN_S_CTRL_BUSOFF);
+     * } else {
+     *     config->status = cpu_to_le32(0);
+     * }
+     */
+
+    memcpy(config, &can->config, sizeof(struct virtio_can_config));
+}
+
+
+static void vhost_user_can_start(VirtIODevice *vdev)
+{
+    VHostUserCan *vhucan = vdev->vhucan;
+    VirtioBus *k = vdev->vbus;
+    int ret;
+    int i;
+
+    DBG("vhost_user_can_start(...)\n");
+
+    if (!k->set_guest_notifiers) {
+        DBG("binding does not support guest notifiers\n");
+        return;
+    }
+
+    ret = vhost_dev_enable_notifiers(vhucan->vhost_dev, vdev);
+    if (ret < 0) {
+        DBG("Error enabling host notifiers: %d\n", -ret);
+        return;
+    }
+
+    ret = k->set_guest_notifiers(k->vdev, vhucan->vhost_dev->nvqs, true);
+    if (ret < 0) {
+        DBG("Error binding guest notifier: %d\n", -ret);
+        goto err_host_notifiers;
+    }
+
+    vhucan->vhost_dev->acked_features = vdev->guest_features;
+
+    ret = vhost_dev_start(vhucan->vhost_dev, vdev, true);
+    if (ret < 0) {
+        DBG("Error starting vhost: %d\n", -ret);
+        goto err_guest_notifiers;
+    }
+
+    /*
+     * guest_notifier_mask/pending not used yet, so just unmask
+     * everything here.  virtio-pci will do the right thing by
+     * enabling/disabling irqfd.
+     */
+    for (i = 0; i < vhucan->vhost_dev->nvqs; i++) {
+        vhost_virtqueue_mask(vhucan->vhost_dev, vdev, i, false);
+    }
+
+    /* Wait a bit for the vrings to be set in vhost-user-device */
+    sleep(1);
+
+    return;
+
+err_guest_notifiers:
+err_host_notifiers:
+    DBG("vhu_start error\n");
+    return;
+}
+
+static void vhost_user_can_stop(VirtIODevice *vdev)
+{
+    DBG("vhost_user_can_stop: not yet implemented\n");
+}
+
+static void vhost_user_can_set_status(VirtIODevice *vdev, uint8_t status)
+{
+    VHostUserCan *vhucan = vdev->vhucan;
+    bool should_start = virtio_device_started(vdev, status);
+    DBG("vhost_user_can_set_status: %d\n", status);
+
+    if (vhucan->vhost_dev->started == should_start) {
+        DBG("can->vhost_dev->started == should_start\n");
+        return;
+    }
+
+    if (should_start) {
+        vhost_user_can_start(vdev);
+    } else {
+        vhost_user_can_stop(vdev);
+    }
+}
+
+static uint64_t vhost_user_can_get_features(VirtIODevice *vdev,
+                                            uint64_t features)
+{
+    VHostUserCan *s = vdev->vhucan;
+
+    DBG("vhost_user_can_get_features()\n");
+
+    return vhost_get_features(s->vhost_dev, user_feature_bits, features);
+}
+
+static void vhost_user_can_can_handle_output(VirtIODevice *vdev, VirtQueue *vq)
+{
+    /*
+     * Not normally called; it's the daemon that handles the queue;
+     * however virtio's cleanup path can call this.
+     */
+    DBG("vhost_user_can_can_handle_output: Not yet implemented!\n");
+}
+
+/*
+ * TODO: Add it later
+ * static void vhost_sound_guest_notifier_mask(VirtIODevice *vdev, int idx,
+ *                                             bool mask)
+ */
+
+/*
+ * TODO: Add it later
+ * static bool vhost_sound_guest_notifier_pending(VirtIODevice *vdev,
+ *                                                int idx)
+ */
+
+static int vhost_user_can_can_config_change(struct vhost_dev *dev)
+{
+    VHostUserCan *vhucan = dev->vdev->vhucan;
+    DBG("vhost_user_can_can_config_change: Not yet implemented!\n");
+
+    int ret = vhost_dev_get_config(dev, (uint8_t *)&vhucan->config,
+                                   sizeof(struct virtio_can_config));
+    if (ret < 0) {
+        DBG("vhost_user_can_sound_config_change error\n");
+        return -1;
+    }
+
+    virtio_notify_config(dev->vdev);
+
+    return 0;
+}
+
+const VhostDevConfigOps can_config_ops = {
+    .vhost_dev_config_notifier = vhost_user_can_can_config_change,
+};
+
+static void vhost_user_can_init(VirtIODevice *vdev);
+
+void vhost_user_can_realize()
+{
+    VirtIODevice *vdev = global_vdev;
+    int ret;
+
+    DBG("vhost_user_can_device_realize\n");
+
+    /* This needs to be added */
+    proxy = (VirtIOMMIOProxy *)malloc(sizeof(VirtIOMMIOProxy));
+    *proxy = (VirtIOMMIOProxy) {
+        .legacy = 1,
+    };
+
+    /* VIRTIO_ID_CAN is 36, check virtio_ids.h in linux*/
+    virtio_dev_init(vdev, "virtio-can", 36, sizeof(vdev->vhucan->config));
+    vhost_user_can_init(global_vdev);
+
+    /* add queues */
+    vdev->vhucan->ctrl_vq = virtio_add_queue(vdev, 64,
+                                             vhost_user_can_can_handle_output);
+    vdev->vhucan->tx_vq = virtio_add_queue(vdev, 64,
+                                           vhost_user_can_can_handle_output);
+    vdev->vhucan->rx_vq = virtio_add_queue(vdev, 64,
+                                           vhost_user_can_can_handle_output);
+    vdev->vhucan->vhost_dev->nvqs = 3;
+    vdev->vhucan->num_queues = 3;
+    vdev->vhucan->queue_size = 64;
+
+    /* NOTE: global_vdev->vqs == vhucan->virtqs */
+    vdev->vqs = (VirtQueue **)malloc(sizeof(VirtQueue *)
+                                     * global_vdev->vhucan->num_queues);
+    vdev->vqs[0] = vdev->vhucan->tx_vq;
+    vdev->vqs[1] = vdev->vhucan->rx_vq;
+    vdev->vqs[2] = vdev->vhucan->ctrl_vq;
+
+    vdev->vhucan->vhost_vqs = (struct vhost_virtqueue *)malloc(
+                                       sizeof(struct vhost_virtqueue) *
+                                       vdev->vhucan->num_queues);
+
+    /* Set up vhost device */
+    vdev->vhucan->vhost_dev->num_queues = vdev->vhucan->num_queues;
+    vdev->vhucan->vhost_dev->nvqs = vdev->vhucan->num_queues;
+    vdev->vhucan->vhost_dev->vqs = vdev->vhucan->vhost_vqs;
+    vdev->vhucan->vhost_dev->vq_index = 0;
+    vdev->vhucan->vhost_dev->backend_features = 0;
+
+    vhost_dev_set_config_notifier(vdev->vhucan->vhost_dev, &can_config_ops);
+
+    /* TODO: Add error handling */
+    vhost_dev_init(vdev->vhucan->vhost_dev);
+
+    /* Pass the new obtained features */
+    global_vdev->host_features = vdev->vhucan->vhost_dev->features;
+
+    ret = vhost_dev_get_config(vdev->vhucan->vhost_dev,
+                               (uint8_t *)&vdev->vhucan->config,
+                               sizeof(struct virtio_can_config));
+    if (ret < 0) {
+        goto vhost_dev_init_failed;
+    }
+
+    vdev->vdev_class->print_config((uint8_t *)&vdev->vhucan->config);
+
+    return;
+
+vhost_dev_init_failed:
+    DBG("vhost_dev_init_failed\n");
+    return;
+}
+
+static void vhost_user_can_device_unrealize(VirtIODevice *vdev)
+{
+    DBG("vhost_user_blk_device_unrealize not yet implemented\n");
+}
+
+static struct vhost_dev *vhost_user_can_get_vhost(VirtIODevice *vdev)
+{
+    VHostUserCan *vhucan = vdev->vhucan;
+    return vhucan->vhost_dev;
+}
+
+static void print_config_can(uint8_t *config_data)
+{
+    struct virtio_can_config *config_strct =
+        (struct virtio_can_config *)config_data;
+
+    DBG("print_config_can:\n");
+
+    /* # of available physical jacks */
+    DBG("\tuint16_t status: %u\n", config_strct->status);
+}
+
+static void virtio_dev_class_init(VirtIODevice *vdev)
+{
+    DBG("virtio_dev_class_init\n");
+
+    vdev->vdev_class = (VirtioDeviceClass *)malloc(sizeof(VirtioDeviceClass));
+    vdev->vdev_class->parent = vdev;
+    vdev->vdev_class->realize = vhost_user_can_realize;
+    vdev->vdev_class->unrealize = vhost_user_can_device_unrealize;
+    vdev->vdev_class->get_config = vhost_user_can_get_config;
+    vdev->vdev_class->get_features = vhost_user_can_get_features;
+    vdev->vdev_class->set_status = vhost_user_can_set_status;
+    vdev->vdev_class->update_mem_table = update_mem_table;
+    vdev->vdev_class->print_config = print_config_can;
+}
+
+static void vhost_user_can_init(VirtIODevice *vdev)
+{
+    DBG("vhost_user_can_init\n");
+
+    VHostUserCan *vhucan = (VHostUserCan *)malloc(sizeof(VHostUserCan));
+    vdev->vhucan = vhucan;
+    vdev->nvqs = &vdev->vhdev->nvqs;
+    vhucan->parent = vdev;
+    vhucan->virtqs = vdev->vqs;
+    vhucan->vhost_dev = vdev->vhdev;
+
+    virtio_dev_class_init(vdev);
+    virtio_loopback_bus_init(vdev->vbus);
+}