This creates the QEMU side of the vhost-user-i2c device which connects
to the remote daemon. It is based of vhost-user-fs code.
Signed-off-by: Viresh Kumar <viresh.ku...@linaro.org>
---
hw/virtio/Kconfig | 5 +
hw/virtio/meson.build | 1 +
hw/virtio/vhost-user-i2c.c | 288 +++++++++++++++++++++++++++++
include/hw/virtio/vhost-user-i2c.h | 28 +++
4 files changed, 322 insertions(+)
create mode 100644 hw/virtio/vhost-user-i2c.c
create mode 100644 include/hw/virtio/vhost-user-i2c.h
diff --git a/hw/virtio/Kconfig b/hw/virtio/Kconfig
index 0eda25c4e1bf..35ab45e2095c 100644
--- a/hw/virtio/Kconfig
+++ b/hw/virtio/Kconfig
@@ -58,3 +58,8 @@ config VIRTIO_MEM
depends on LINUX
depends on VIRTIO_MEM_SUPPORTED
select MEM_DEVICE
+
+config VHOST_USER_I2C
+ bool
+ default y
+ depends on VIRTIO && VHOST_USER
diff --git a/hw/virtio/meson.build b/hw/virtio/meson.build
index fbff9bc9d4de..1a0d736a0db5 100644
--- a/hw/virtio/meson.build
+++ b/hw/virtio/meson.build
@@ -25,6 +25,7 @@ virtio_ss.add(when: 'CONFIG_VHOST_USER_VSOCK', if_true:
files('vhost-user-vsock.
virtio_ss.add(when: 'CONFIG_VIRTIO_RNG', if_true: files('virtio-rng.c'))
virtio_ss.add(when: 'CONFIG_VIRTIO_IOMMU', if_true: files('virtio-iommu.c'))
virtio_ss.add(when: 'CONFIG_VIRTIO_MEM', if_true: files('virtio-mem.c'))
+virtio_ss.add(when: 'CONFIG_VHOST_USER_I2C', if_true:
files('vhost-user-i2c.c'))
virtio_pci_ss = ss.source_set()
virtio_pci_ss.add(when: 'CONFIG_VHOST_VSOCK', if_true:
files('vhost-vsock-pci.c'))
diff --git a/hw/virtio/vhost-user-i2c.c b/hw/virtio/vhost-user-i2c.c
new file mode 100644
index 000000000000..d172632bb0cd
--- /dev/null
+++ b/hw/virtio/vhost-user-i2c.c
@@ -0,0 +1,288 @@
+/*
+ * Vhost-user i2c virtio device
+ *
+ * Copyright (c) 2021 Viresh Kumar <viresh.ku...@linaro.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "hw/qdev-properties.h"
+#include "hw/virtio/virtio-bus.h"
+#include "hw/virtio/vhost-user-i2c.h"
+#include "qemu/error-report.h"
+#include "standard-headers/linux/virtio_ids.h"
+
+/* Remove this once the header is updated in Linux kernel */
+#ifndef VIRTIO_ID_I2C_ADAPTER
+#define VIRTIO_ID_I2C_ADAPTER 34
+#endif
+
+static void vu_i2c_start(VirtIODevice *vdev)
+{
+ BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
+ VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+ VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
+ int ret, i;
+
+ if (!k->set_guest_notifiers) {
+ error_report("binding does not support guest notifiers");
+ return;
+ }
+
+ ret = vhost_dev_enable_notifiers(&i2c->vhost_dev, vdev);
+ if (ret < 0) {
+ error_report("Error enabling host notifiers: %d", -ret);
+ return;
+ }
+
+ ret = k->set_guest_notifiers(qbus->parent, i2c->vhost_dev.nvqs, true);
+ if (ret < 0) {
+ error_report("Error binding guest notifier: %d", -ret);
+ goto err_host_notifiers;
+ }
+
+ i2c->vhost_dev.acked_features = vdev->guest_features;
+
+ ret = vhost_dev_start(&i2c->vhost_dev, vdev);
+ if (ret < 0) {
+ error_report("Error starting vhost-user-i2c: %d", -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 < i2c->vhost_dev.nvqs; i++) {
+ vhost_virtqueue_mask(&i2c->vhost_dev, vdev, i, false);
+ }
+
+ return;
+
+err_guest_notifiers:
+ k->set_guest_notifiers(qbus->parent, i2c->vhost_dev.nvqs, false);
+err_host_notifiers:
+ vhost_dev_disable_notifiers(&i2c->vhost_dev, vdev);
+}
+
+static void vu_i2c_stop(VirtIODevice *vdev)
+{
+ VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
+ BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
+ VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+ int ret;
+
+ if (!k->set_guest_notifiers) {
+ return;
+ }
+
+ vhost_dev_stop(&i2c->vhost_dev, vdev);
+
+ ret = k->set_guest_notifiers(qbus->parent, i2c->vhost_dev.nvqs, false);
+ if (ret < 0) {
+ error_report("vhost guest notifier cleanup failed: %d", ret);
+ return;
+ }
+
+ vhost_dev_disable_notifiers(&i2c->vhost_dev, vdev);
+}
+
+static void vu_i2c_set_status(VirtIODevice *vdev, uint8_t status)
+{
+ VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
+ bool should_start = status & VIRTIO_CONFIG_S_DRIVER_OK;
+
+ if (!vdev->vm_running) {
+ should_start = false;
+ }
+
+ if (i2c->vhost_dev.started == should_start) {
+ return;
+ }
+
+ if (should_start) {
+ vu_i2c_start(vdev);
+ } else {
+ vu_i2c_stop(vdev);
+ }
+}
+
+static uint64_t vu_i2c_get_features(VirtIODevice *vdev,
+ uint64_t requested_features, Error **errp)
+{
+ /* No feature bits used yet */
+ return requested_features;
+}
+
+static void vu_i2c_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.
+ */
+}
+
+static void vu_i2c_guest_notifier_mask(VirtIODevice *vdev, int idx, bool mask)
+{
+ VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
+
+ vhost_virtqueue_mask(&i2c->vhost_dev, vdev, idx, mask);
+}
+
+static bool vu_i2c_guest_notifier_pending(VirtIODevice *vdev, int idx)
+{
+ VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
+
+ return vhost_virtqueue_pending(&i2c->vhost_dev, idx);
+}
+
+static void do_vhost_user_cleanup(VirtIODevice *vdev, VHostUserI2C *i2c)
+{
+ vhost_user_cleanup(&i2c->vhost_user);
+ virtio_delete_queue(i2c->vq);
+ virtio_cleanup(vdev);
+ g_free(i2c->vhost_dev.vqs);
+ i2c->vhost_dev.vqs = NULL;
+}
+
+static int vu_i2c_connect(DeviceState *dev)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
+
+ if (i2c->connected) {
+ return 0;
+ }
+ i2c->connected = true;
+
+ /* restore vhost state */
+ if (virtio_device_started(vdev, vdev->status)) {
+ vu_i2c_start(vdev);
+ }
+
+ return 0;
+}
+
+static void vu_i2c_disconnect(DeviceState *dev)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
+
+ if (!i2c->connected) {
+ return;
+ }
+ i2c->connected = false;
+
+ if (i2c->vhost_dev.started) {
+ vu_i2c_stop(vdev);
+ }
+}
+
+static void vu_i2c_event(void *opaque, QEMUChrEvent event)
+{
+ DeviceState *dev = opaque;
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
+
+ switch (event) {
+ case CHR_EVENT_OPENED:
+ if (vu_i2c_connect(dev) < 0) {
+ qemu_chr_fe_disconnect(&i2c->chardev);
+ return;
+ }
+ break;
+ case CHR_EVENT_CLOSED:
+ vu_i2c_disconnect(dev);
+ break;
+ case CHR_EVENT_BREAK:
+ case CHR_EVENT_MUX_IN:
+ case CHR_EVENT_MUX_OUT:
+ /* Ignore */
+ break;
+ }
+}
+
+static void vu_i2c_device_realize(DeviceState *dev, Error **errp)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VHostUserI2C *i2c = VHOST_USER_I2C(dev);
+ int ret;
+
+ if (!i2c->chardev.chr) {
+ error_setg(errp, "vhost-user-i2c: missing chardev");
+ return;
+ }
+
+ if (!vhost_user_init(&i2c->vhost_user, &i2c->chardev, errp)) {
+ return;
+ }
+
+ virtio_init(vdev, "vhost-user-i2c", VIRTIO_ID_I2C_ADAPTER, 0);
+
+ i2c->vhost_dev.nvqs = 1;
+ i2c->vq = virtio_add_queue(vdev, 4, vu_i2c_handle_output);
+ i2c->vhost_dev.vqs = g_new0(struct vhost_virtqueue, i2c->vhost_dev.nvqs);
+
+ ret = vhost_dev_init(&i2c->vhost_dev, &i2c->vhost_user,
+ VHOST_BACKEND_TYPE_USER, 0, errp);
+ if (ret < 0) {
+ do_vhost_user_cleanup(vdev, i2c);
+ }
+
+ qemu_chr_fe_set_handlers(&i2c->chardev, NULL, NULL, vu_i2c_event, NULL,
+ dev, NULL, true);
+}
+
+static void vu_i2c_device_unrealize(DeviceState *dev)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VHostUserI2C *i2c = VHOST_USER_I2C(dev);
+
+ /* This will stop vhost backend if appropriate. */
+ vu_i2c_set_status(vdev, 0);
+ vhost_dev_cleanup(&i2c->vhost_dev);
+ do_vhost_user_cleanup(vdev, i2c);
+}
+
+static const VMStateDescription vu_i2c_vmstate = {
+ .name = "vhost-user-i2c",
+ .unmigratable = 1,
+};
+
+static Property vu_i2c_properties[] = {
+ DEFINE_PROP_CHR("chardev", VHostUserI2C, chardev),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void vu_i2c_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
+
+ device_class_set_props(dc, vu_i2c_properties);
+ dc->vmsd = &vu_i2c_vmstate;
+ set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
+ vdc->realize = vu_i2c_device_realize;
+ vdc->unrealize = vu_i2c_device_unrealize;
+ vdc->get_features = vu_i2c_get_features;
+ vdc->set_status = vu_i2c_set_status;
+ vdc->guest_notifier_mask = vu_i2c_guest_notifier_mask;
+ vdc->guest_notifier_pending = vu_i2c_guest_notifier_pending;
+}
+
+static const TypeInfo vu_i2c_info = {
+ .name = TYPE_VHOST_USER_I2C,
+ .parent = TYPE_VIRTIO_DEVICE,
+ .instance_size = sizeof(VHostUserI2C),
+ .class_init = vu_i2c_class_init,
+};
+
+static void vu_i2c_register_types(void)
+{
+ type_register_static(&vu_i2c_info);
+}
+
+type_init(vu_i2c_register_types)
diff --git a/include/hw/virtio/vhost-user-i2c.h
b/include/hw/virtio/vhost-user-i2c.h
new file mode 100644
index 000000000000..deae47a76d55
--- /dev/null
+++ b/include/hw/virtio/vhost-user-i2c.h
@@ -0,0 +1,28 @@
+/*
+ * Vhost-user i2c virtio device
+ *
+ * Copyright (c) 2021 Viresh Kumar <viresh.ku...@linaro.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef _QEMU_VHOST_USER_I2C_H
+#define _QEMU_VHOST_USER_I2C_H
+
+#include "hw/virtio/vhost.h"
+#include "hw/virtio/vhost-user.h"
+
+#define TYPE_VHOST_USER_I2C "vhost-user-i2c-device"
+OBJECT_DECLARE_SIMPLE_TYPE(VHostUserI2C, VHOST_USER_I2C)
+
+struct VHostUserI2C {
+ VirtIODevice parent;
+ CharBackend chardev;
+ struct vhost_virtqueue *vhost_vq;
+ struct vhost_dev vhost_dev;
+ VhostUserState vhost_user;
+ VirtQueue *vq;
+ bool connected;
+};
+
+#endif /* _QEMU_VHOST_USER_I2C_H */
--
2.31.1.272.g89b43f80a514
