* [PATCH v5 1/3] vhost-user-rng: Add vhost-user-rng implementation
2021-10-12 20:59 [PATCH v5 0/3] virtio: Add vhost-user based RNG Mathieu Poirier
@ 2021-10-12 20:59 ` Mathieu Poirier
2021-10-12 20:59 ` [PATCH v5 2/3] vhost-user-rng-pci: Add vhost-user-rng-pci implementation Mathieu Poirier
2021-10-12 20:59 ` [PATCH v5 3/3] docs: Add documentation for vhost based RNG implementation Mathieu Poirier
2 siblings, 0 replies; 4+ messages in thread
From: Mathieu Poirier @ 2021-10-12 20:59 UTC (permalink / raw)
To: mst; +Cc: alex.bennee, qemu-devel
Introduce a random number generator (RNG) backend that communicates
with a vhost-user server to retrieve entropy. That way other VMM
that comply with the vhost user protocl can use the same vhost-user
daemon without having to write yet another RNG driver.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
hw/virtio/Kconfig | 5 +
hw/virtio/meson.build | 1 +
hw/virtio/vhost-user-rng.c | 289 +++++++++++++++++++++++++++++
include/hw/virtio/vhost-user-rng.h | 33 ++++
4 files changed, 328 insertions(+)
create mode 100644 hw/virtio/vhost-user-rng.c
create mode 100644 include/hw/virtio/vhost-user-rng.h
diff --git a/hw/virtio/Kconfig b/hw/virtio/Kconfig
index 35ab45e2095c..c144d42f9bd0 100644
--- a/hw/virtio/Kconfig
+++ b/hw/virtio/Kconfig
@@ -63,3 +63,8 @@ config VHOST_USER_I2C
bool
default y
depends on VIRTIO && VHOST_USER
+
+config VHOST_USER_RNG
+ bool
+ default y
+ depends on VIRTIO && VHOST_USER
diff --git a/hw/virtio/meson.build b/hw/virtio/meson.build
index bc352a600911..ae6b2cde1068 100644
--- a/hw/virtio/meson.build
+++ b/hw/virtio/meson.build
@@ -27,6 +27,7 @@ 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_ss.add(when: ['CONFIG_VIRTIO_PCI', 'CONFIG_VHOST_USER_I2C'], if_true: files('vhost-user-i2c-pci.c'))
+virtio_ss.add(when: 'CONFIG_VHOST_USER_RNG', if_true: files('vhost-user-rng.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-rng.c b/hw/virtio/vhost-user-rng.c
new file mode 100644
index 000000000000..209ee5bf9acd
--- /dev/null
+++ b/hw/virtio/vhost-user-rng.c
@@ -0,0 +1,289 @@
+/*
+ * Vhost-user RNG virtio device
+ *
+ * Copyright (c) 2021 Mathieu Poirier <mathieu.poirier@linaro.org>
+ *
+ * Implementation seriously tailored on vhost-user-i2c.c
+ *
+ * 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-rng.h"
+#include "qemu/error-report.h"
+#include "standard-headers/linux/virtio_ids.h"
+
+static void vu_rng_start(VirtIODevice *vdev)
+{
+ VHostUserRNG *rng = VHOST_USER_RNG(vdev);
+ BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
+ VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+ int ret;
+ int i;
+
+ if (!k->set_guest_notifiers) {
+ error_report("binding does not support guest notifiers");
+ return;
+ }
+
+ ret = vhost_dev_enable_notifiers(&rng->vhost_dev, vdev);
+ if (ret < 0) {
+ error_report("Error enabling host notifiers: %d", -ret);
+ return;
+ }
+
+ ret = k->set_guest_notifiers(qbus->parent, rng->vhost_dev.nvqs, true);
+ if (ret < 0) {
+ error_report("Error binding guest notifier: %d", -ret);
+ goto err_host_notifiers;
+ }
+
+ rng->vhost_dev.acked_features = vdev->guest_features;
+ ret = vhost_dev_start(&rng->vhost_dev, vdev);
+ if (ret < 0) {
+ error_report("Error starting vhost-user-rng: %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 < rng->vhost_dev.nvqs; i++) {
+ vhost_virtqueue_mask(&rng->vhost_dev, vdev, i, false);
+ }
+
+ return;
+
+err_guest_notifiers:
+ k->set_guest_notifiers(qbus->parent, rng->vhost_dev.nvqs, false);
+err_host_notifiers:
+ vhost_dev_disable_notifiers(&rng->vhost_dev, vdev);
+}
+
+static void vu_rng_stop(VirtIODevice *vdev)
+{
+ VHostUserRNG *rng = VHOST_USER_RNG(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(&rng->vhost_dev, vdev);
+
+ ret = k->set_guest_notifiers(qbus->parent, rng->vhost_dev.nvqs, false);
+ if (ret < 0) {
+ error_report("vhost guest notifier cleanup failed: %d", ret);
+ return;
+ }
+
+ vhost_dev_disable_notifiers(&rng->vhost_dev, vdev);
+}
+
+static void vu_rng_set_status(VirtIODevice *vdev, uint8_t status)
+{
+ VHostUserRNG *rng = VHOST_USER_RNG(vdev);
+ bool should_start = status & VIRTIO_CONFIG_S_DRIVER_OK;
+
+ if (!vdev->vm_running) {
+ should_start = false;
+ }
+
+ if (rng->vhost_dev.started == should_start) {
+ return;
+ }
+
+ if (should_start) {
+ vu_rng_start(vdev);
+ } else {
+ vu_rng_stop(vdev);
+ }
+}
+
+static uint64_t vu_rng_get_features(VirtIODevice *vdev,
+ uint64_t requested_features, Error **errp)
+{
+ /* No feature bits used yet */
+ return requested_features;
+}
+
+static void vu_rng_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_rng_guest_notifier_mask(VirtIODevice *vdev, int idx, bool mask)
+{
+ VHostUserRNG *rng = VHOST_USER_RNG(vdev);
+
+ vhost_virtqueue_mask(&rng->vhost_dev, vdev, idx, mask);
+}
+
+static bool vu_rng_guest_notifier_pending(VirtIODevice *vdev, int idx)
+{
+ VHostUserRNG *rng = VHOST_USER_RNG(vdev);
+
+ return vhost_virtqueue_pending(&rng->vhost_dev, idx);
+}
+
+static void vu_rng_connect(DeviceState *dev)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VHostUserRNG *rng = VHOST_USER_RNG(vdev);
+
+ if (rng->connected) {
+ return;
+ }
+
+ rng->connected = true;
+
+ /* restore vhost state */
+ if (virtio_device_started(vdev, vdev->status)) {
+ vu_rng_start(vdev);
+ }
+}
+
+static void vu_rng_disconnect(DeviceState *dev)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VHostUserRNG *rng = VHOST_USER_RNG(vdev);
+
+ if (!rng->connected) {
+ return;
+ }
+
+ rng->connected = false;
+
+ if (rng->vhost_dev.started) {
+ vu_rng_stop(vdev);
+ }
+}
+
+static void vu_rng_event(void *opaque, QEMUChrEvent event)
+{
+ DeviceState *dev = opaque;
+
+ switch (event) {
+ case CHR_EVENT_OPENED:
+ vu_rng_connect(dev);
+ break;
+ case CHR_EVENT_CLOSED:
+ vu_rng_disconnect(dev);
+ break;
+ case CHR_EVENT_BREAK:
+ case CHR_EVENT_MUX_IN:
+ case CHR_EVENT_MUX_OUT:
+ /* Ignore */
+ break;
+ }
+}
+
+static void vu_rng_device_realize(DeviceState *dev, Error **errp)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VHostUserRNG *rng = VHOST_USER_RNG(dev);
+ int ret;
+
+ if (!rng->chardev.chr) {
+ error_setg(errp, "missing chardev");
+ return;
+ }
+
+ if (!vhost_user_init(&rng->vhost_user, &rng->chardev, errp)) {
+ return;
+ }
+
+ virtio_init(vdev, "vhost-user-rng", VIRTIO_ID_RNG, 0);
+
+ rng->req_vq = virtio_add_queue(vdev, 4, vu_rng_handle_output);
+ if (!rng->req_vq) {
+ error_setg_errno(errp, -1, "virtio_add_queue() failed");
+ goto virtio_add_queue_failed;
+ }
+
+ rng->vhost_dev.nvqs = 1;
+ rng->vhost_dev.vqs = g_new0(struct vhost_virtqueue, rng->vhost_dev.nvqs);
+ ret = vhost_dev_init(&rng->vhost_dev, &rng->vhost_user,
+ VHOST_BACKEND_TYPE_USER, 0, errp);
+ if (ret < 0) {
+ error_setg_errno(errp, -ret, "vhost_dev_init() failed");
+ goto vhost_dev_init_failed;
+ }
+
+ qemu_chr_fe_set_handlers(&rng->chardev, NULL, NULL, vu_rng_event, NULL,
+ dev, NULL, true);
+
+ return;
+
+vhost_dev_init_failed:
+ virtio_delete_queue(rng->req_vq);
+virtio_add_queue_failed:
+ virtio_cleanup(vdev);
+ vhost_user_cleanup(&rng->vhost_user);
+}
+
+static void vu_rng_device_unrealize(DeviceState *dev)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+ VHostUserRNG *rng = VHOST_USER_RNG(dev);
+
+ vu_rng_set_status(vdev, 0);
+
+ vhost_dev_cleanup(&rng->vhost_dev);
+ g_free(rng->vhost_dev.vqs);
+ rng->vhost_dev.vqs = NULL;
+ virtio_delete_queue(rng->req_vq);
+ virtio_cleanup(vdev);
+ vhost_user_cleanup(&rng->vhost_user);
+}
+
+static const VMStateDescription vu_rng_vmstate = {
+ .name = "vhost-user-rng",
+ .unmigratable = 1,
+};
+
+static Property vu_rng_properties[] = {
+ DEFINE_PROP_CHR("chardev", VHostUserRNG, chardev),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void vu_rng_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
+
+ device_class_set_props(dc, vu_rng_properties);
+ dc->vmsd = &vu_rng_vmstate;
+ set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
+
+ vdc->realize = vu_rng_device_realize;
+ vdc->unrealize = vu_rng_device_unrealize;
+ vdc->get_features = vu_rng_get_features;
+ vdc->set_status = vu_rng_set_status;
+ vdc->guest_notifier_mask = vu_rng_guest_notifier_mask;
+ vdc->guest_notifier_pending = vu_rng_guest_notifier_pending;
+}
+
+static const TypeInfo vu_rng_info = {
+ .name = TYPE_VHOST_USER_RNG,
+ .parent = TYPE_VIRTIO_DEVICE,
+ .instance_size = sizeof(VHostUserRNG),
+ .class_init = vu_rng_class_init,
+};
+
+static void vu_rng_register_types(void)
+{
+ type_register_static(&vu_rng_info);
+}
+
+type_init(vu_rng_register_types)
diff --git a/include/hw/virtio/vhost-user-rng.h b/include/hw/virtio/vhost-user-rng.h
new file mode 100644
index 000000000000..071539996d1d
--- /dev/null
+++ b/include/hw/virtio/vhost-user-rng.h
@@ -0,0 +1,33 @@
+/*
+ * Vhost-user RNG virtio device
+ *
+ * Copyright (c) 2021 Mathieu Poirier <mathieu.poirier@linaro.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef _QEMU_VHOST_USER_RNG_H
+#define _QEMU_VHOST_USER_RNG_H
+
+#include "hw/virtio/virtio.h"
+#include "hw/virtio/vhost.h"
+#include "hw/virtio/vhost-user.h"
+#include "chardev/char-fe.h"
+
+#define TYPE_VHOST_USER_RNG "vhost-user-rng"
+OBJECT_DECLARE_SIMPLE_TYPE(VHostUserRNG, VHOST_USER_RNG)
+
+struct VHostUserRNG {
+ /*< private >*/
+ VirtIODevice parent;
+ CharBackend chardev;
+ struct vhost_virtqueue *vhost_vq;
+ struct vhost_dev vhost_dev;
+ VhostUserState vhost_user;
+ VirtQueue *req_vq;
+ bool connected;
+
+ /*< public >*/
+};
+
+#endif /* _QEMU_VHOST_USER_RNG_H */
--
2.25.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH v5 2/3] vhost-user-rng-pci: Add vhost-user-rng-pci implementation
2021-10-12 20:59 [PATCH v5 0/3] virtio: Add vhost-user based RNG Mathieu Poirier
2021-10-12 20:59 ` [PATCH v5 1/3] vhost-user-rng: Add vhost-user-rng implementation Mathieu Poirier
@ 2021-10-12 20:59 ` Mathieu Poirier
2021-10-12 20:59 ` [PATCH v5 3/3] docs: Add documentation for vhost based RNG implementation Mathieu Poirier
2 siblings, 0 replies; 4+ messages in thread
From: Mathieu Poirier @ 2021-10-12 20:59 UTC (permalink / raw)
To: mst; +Cc: alex.bennee, qemu-devel
This patch provides a PCI bus interface to the vhost-user-rng backend.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
hw/virtio/meson.build | 1 +
hw/virtio/vhost-user-rng-pci.c | 79 ++++++++++++++++++++++++++++++++++
2 files changed, 80 insertions(+)
create mode 100644 hw/virtio/vhost-user-rng-pci.c
diff --git a/hw/virtio/meson.build b/hw/virtio/meson.build
index ae6b2cde1068..521f7d64a86a 100644
--- a/hw/virtio/meson.build
+++ b/hw/virtio/meson.build
@@ -28,6 +28,7 @@ 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_ss.add(when: ['CONFIG_VIRTIO_PCI', 'CONFIG_VHOST_USER_I2C'], if_true: files('vhost-user-i2c-pci.c'))
virtio_ss.add(when: 'CONFIG_VHOST_USER_RNG', if_true: files('vhost-user-rng.c'))
+virtio_ss.add(when: ['CONFIG_VHOST_USER_RNG', 'CONFIG_VIRTIO_PCI'], if_true: files('vhost-user-rng-pci.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-rng-pci.c b/hw/virtio/vhost-user-rng-pci.c
new file mode 100644
index 000000000000..c83dc8681385
--- /dev/null
+++ b/hw/virtio/vhost-user-rng-pci.c
@@ -0,0 +1,79 @@
+/*
+ * Vhost-user RNG virtio device PCI glue
+ *
+ * Copyright (c) 2021 Mathieu Poirier <mathieu.poirier@linaro.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "hw/qdev-properties.h"
+#include "hw/virtio/vhost-user-rng.h"
+#include "virtio-pci.h"
+
+struct VHostUserRNGPCI {
+ VirtIOPCIProxy parent_obj;
+ VHostUserRNG vdev;
+};
+
+typedef struct VHostUserRNGPCI VHostUserRNGPCI;
+
+#define TYPE_VHOST_USER_RNG_PCI "vhost-user-rng-pci-base"
+
+DECLARE_INSTANCE_CHECKER(VHostUserRNGPCI, VHOST_USER_RNG_PCI,
+ TYPE_VHOST_USER_RNG_PCI)
+
+static Property vhost_user_rng_pci_properties[] = {
+ DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors,
+ DEV_NVECTORS_UNSPECIFIED),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void vhost_user_rng_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp)
+{
+ VHostUserRNGPCI *dev = VHOST_USER_RNG_PCI(vpci_dev);
+ DeviceState *vdev = DEVICE(&dev->vdev);
+
+ if (vpci_dev->nvectors == DEV_NVECTORS_UNSPECIFIED) {
+ vpci_dev->nvectors = 1;
+ }
+
+ qdev_realize(vdev, BUS(&vpci_dev->bus), errp);
+}
+
+static void vhost_user_rng_pci_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ VirtioPCIClass *k = VIRTIO_PCI_CLASS(klass);
+ PCIDeviceClass *pcidev_k = PCI_DEVICE_CLASS(klass);
+ k->realize = vhost_user_rng_pci_realize;
+ set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
+ device_class_set_props(dc, vhost_user_rng_pci_properties);
+ pcidev_k->vendor_id = PCI_VENDOR_ID_REDHAT_QUMRANET;
+ pcidev_k->device_id = 0; /* Set by virtio-pci based on virtio id */
+ pcidev_k->revision = 0x00;
+ pcidev_k->class_id = PCI_CLASS_OTHERS;
+}
+
+static void vhost_user_rng_pci_instance_init(Object *obj)
+{
+ VHostUserRNGPCI *dev = VHOST_USER_RNG_PCI(obj);
+
+ virtio_instance_init_common(obj, &dev->vdev, sizeof(dev->vdev),
+ TYPE_VHOST_USER_RNG);
+}
+
+static const VirtioPCIDeviceTypeInfo vhost_user_rng_pci_info = {
+ .base_name = TYPE_VHOST_USER_RNG_PCI,
+ .non_transitional_name = "vhost-user-rng-pci",
+ .instance_size = sizeof(VHostUserRNGPCI),
+ .instance_init = vhost_user_rng_pci_instance_init,
+ .class_init = vhost_user_rng_pci_class_init,
+};
+
+static void vhost_user_rng_pci_register(void)
+{
+ virtio_pci_types_register(&vhost_user_rng_pci_info);
+}
+
+type_init(vhost_user_rng_pci_register);
--
2.25.1
^ permalink raw reply related [flat|nested] 4+ messages in thread