Add virtio-loopback-adapter

The virtio-loopback-adapter is part of the Virtio Loopback
architecture detailed in the following link:
  https://git.virtualopensystems.com/virtio-loopback/docs

The following vhost-user devices are supported:
- vhost-user-blk
- vhost-user-rng
- vhost-user-input
- vhost-user-gpio
- vhost-user-sound

Bug-AGL: SPEC-4834
Change-Id: I4edb28faf370992f5f45390f5c4240a0f5c3084c
Signed-off-by: Angelos Mouzakitis <a.mouzakitis@virtualopensystems.com>

1 files changed, 313 insertions, 0 deletions

diff --git a/vhost_user_sound.c b/vhost_user_sound.c
new file mode 100644
index 0000000..1e4c5cf
--- /dev/null
+++ b/vhost_user_sound.c
@@ -0,0 +1,313 @@
+/*
+ * Based on vhost-user-sound.c of QEMU project
+ *
+ * Copyright 2020 Red Hat, Inc.
+ *
+ * Copyright (c) 2023 Virtual Open Systems SAS.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * (at your option) any later version.  See the COPYING file in the
+ * top-level directory.
+ *
+ */
+
+
+#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_sound.h"
+
+#ifdef DEBUG
+#define DBG(...) printf("vhost-user-sound: " __VA_ARGS__)
+#else
+#define DBG(...)
+#endif /* DEBUG */
+
+/***************************** vhost-user-sound ******************************/
+
+/*
+ * Features supported by the vhost-user-sound frontend:
+ *     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 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 vus_get_config(VirtIODevice *vdev, uint8_t *config)
+{
+    VHostUserSound *snd = vdev->vhusnd;
+
+    memcpy(config, &snd->config, sizeof(struct virtio_snd_config));
+}
+
+
+static void vus_start(VirtIODevice *vdev)
+{
+    VHostUserSound *vhusnd = vdev->vhusnd;
+    VirtioBus *k = vdev->vbus;
+    int ret;
+    int i;
+
+    DBG("vus_start(...)\n");
+
+    if (!k->set_guest_notifiers) {
+        DBG("binding does not support guest notifiers\n");
+        return;
+    }
+
+    ret = vhost_dev_enable_notifiers(vhusnd->vhost_dev, vdev);
+    if (ret < 0) {
+        DBG("Error enabling host notifiers: %d\n", -ret);
+        return;
+    }
+
+    ret = k->set_guest_notifiers(k->vdev, vhusnd->vhost_dev->nvqs, true);
+    if (ret < 0) {
+        DBG("Error binding guest notifier: %d\n", -ret);
+        goto err_host_notifiers;
+    }
+
+    vhusnd->vhost_dev->acked_features = vdev->guest_features;
+
+    ret = vhost_dev_start(vhusnd->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 < vhusnd->vhost_dev->nvqs; i++) {
+        vhost_virtqueue_mask(vhusnd->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 vus_stop(VirtIODevice *vdev)
+{
+    DBG("vus_stop: not yet implemented\n");
+}
+
+static void vus_set_status(VirtIODevice *vdev, uint8_t status)
+{
+    VHostUserSound *vhusnd = vdev->vhusnd;
+    bool should_start = virtio_device_started(vdev, status);
+    DBG("vus_set_status\n");
+
+    if (vhusnd->vhost_dev->started == should_start) {
+        DBG("snd->vhost_dev->started == should_start\n");
+        return;
+    }
+
+    if (should_start) {
+        vus_start(vdev);
+    } else {
+        vus_stop(vdev);
+    }
+}
+
+static uint64_t vus_get_features(VirtIODevice *vdev, uint64_t features)
+{
+    VHostUserSound *s = vdev->vhusnd;
+
+    DBG("vus_get_features()\n");
+
+    return vhost_get_features(s->vhost_dev, user_feature_bits, features);
+}
+
+static void vus_snd_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.
+     */
+}
+
+/*
+ * 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 vus_sound_config_change(struct vhost_dev *dev)
+{
+    VHostUserSound *vhusnd = dev->vdev->vhusnd;
+    DBG("vus_sound_config_change\n");
+
+    int ret = vhost_dev_get_config(dev, (uint8_t *)&vhusnd->config,
+                                   sizeof(struct virtio_snd_config));
+    if (ret < 0) {
+        DBG("vus_sound_config_change error\n");
+        return -1;
+    }
+
+    virtio_notify_config(dev->vdev);
+
+    return 0;
+}
+
+const VhostDevConfigOps snd_config_ops = {
+    .vhost_dev_config_notifier = vus_sound_config_change,
+};
+
+static void vhost_user_snd_init(VirtIODevice *vdev);
+
+void vus_device_realize()
+{
+    VirtIODevice *vdev = global_vdev;
+    int ret;
+
+    DBG("vus_device_realize\n");
+
+    /* This needs to be added */
+    proxy = (VirtIOMMIOProxy *)malloc(sizeof(VirtIOMMIOProxy));
+    *proxy = (VirtIOMMIOProxy) {
+        .legacy = 1,
+    };
+
+    /* VIRTIO_ID_SOUND is 25, check virtio_ids.h in linux*/
+    virtio_dev_init(vdev, "virtio-sound", 25, sizeof(vdev->vhusnd->config));
+    vhost_user_snd_init(global_vdev);
+
+    /* add queues */
+    vdev->vhusnd->ctrl_vq = virtio_add_queue(vdev, 64, vus_snd_handle_output);
+    vdev->vhusnd->event_vq = virtio_add_queue(vdev, 64, vus_snd_handle_output);
+    vdev->vhusnd->tx_vq = virtio_add_queue(vdev, 64, vus_snd_handle_output);
+    vdev->vhusnd->rx_vq = virtio_add_queue(vdev, 64, vus_snd_handle_output);
+    vdev->vhusnd->vhost_dev->nvqs = 4;
+    vdev->vhusnd->num_queues = 4;
+    vdev->vhusnd->queue_size = 64;
+
+    /* NOTE: global_vdev->vqs == vhublk->virtqs */
+    vdev->vqs = (VirtQueue **)malloc(sizeof(VirtQueue *)
+                                     * global_vdev->vhusnd->num_queues);
+    vdev->vqs[0] = vdev->vhusnd->ctrl_vq;
+    vdev->vqs[1] = vdev->vhusnd->event_vq;
+    vdev->vqs[2] = vdev->vhusnd->tx_vq;
+    vdev->vqs[3] = vdev->vhusnd->rx_vq;
+
+    vdev->vhusnd->vhost_vqs = (struct vhost_virtqueue *)malloc(
+                                       sizeof(struct vhost_virtqueue) *
+                                       vdev->vhusnd->num_queues);
+
+    /* Set up vhost device */
+    vdev->vhusnd->vhost_dev->num_queues = vdev->vhusnd->num_queues;
+    vdev->vhusnd->vhost_dev->nvqs = vdev->vhusnd->num_queues;
+    vdev->vhusnd->vhost_dev->vqs = vdev->vhusnd->vhost_vqs;
+    vdev->vhusnd->vhost_dev->vq_index = 0;
+    vdev->vhusnd->vhost_dev->backend_features = 0;
+
+    vhost_dev_set_config_notifier(vdev->vhusnd->vhost_dev, &snd_config_ops);
+
+    /* TODO: Add error handling */
+    vhost_dev_init(vdev->vhusnd->vhost_dev);
+
+    /* Pass the new obtained features */
+    global_vdev->host_features = vdev->vhusnd->vhost_dev->features;
+
+    ret = vhost_dev_get_config(vdev->vhusnd->vhost_dev,
+                               (uint8_t *)&vdev->vhusnd->config,
+                               sizeof(struct virtio_snd_config));
+    if (ret < 0) {
+        goto vhost_dev_init_failed;
+    }
+
+    vdev->vdev_class->print_config((uint8_t *)&vdev->vhusnd->config);
+
+    return;
+
+vhost_dev_init_failed:
+    DBG("vhost_dev_init_failed\n");
+    return;
+}
+
+static void vus_device_unrealize(VirtIODevice *vdev)
+{
+    DBG("vhost_user_blk_device_unrealize not yet implemented\n");
+}
+
+static struct vhost_dev *vus_get_vhost(VirtIODevice *vdev)
+{
+    VHostUserSound *vhusnd = vdev->vhusnd;
+    return vhusnd->vhost_dev;
+}
+
+static void print_config_snd(uint8_t *config_data)
+{
+    struct virtio_snd_config *config_strct =
+        (struct virtio_snd_config *)config_data;
+
+    DBG("print_config_snd:\n");
+
+    /* # of available physical jacks */
+    DBG("\tuint32_t jacks: %u\n", config_strct->jacks);
+    /* # of available PCM streams */
+    DBG("\tuint32_t streams: %u\n", config_strct->streams);
+    /* # of available channel maps */
+    DBG("\tuint32_t chmaps: %u\n", config_strct->chmaps);
+}
+
+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 = vus_device_realize;
+    vdev->vdev_class->unrealize = vus_device_unrealize;
+    vdev->vdev_class->get_config = vus_get_config;
+    vdev->vdev_class->get_features = vus_get_features;
+    vdev->vdev_class->set_status = vus_set_status;
+    vdev->vdev_class->update_mem_table = update_mem_table;
+    vdev->vdev_class->print_config = print_config_snd;
+}
+
+static void vhost_user_snd_init(VirtIODevice *vdev)
+{
+
+    DBG("vhost_user_blk_init\n");
+
+    VHostUserSound *vhusnd = (VHostUserSound *)malloc(sizeof(VHostUserSound));
+    vdev->vhusnd = vhusnd;
+    vdev->nvqs = &vdev->vhdev->nvqs;
+    vhusnd->parent = vdev;
+    vhusnd->virtqs = vdev->vqs;
+    vhusnd->vhost_dev = vdev->vhdev;
+
+    virtio_dev_class_init(vdev);
+    virtio_loopback_bus_init(vdev->vbus);
+}