[PATCH 3/3] vhost-vdpa-blk: Introduce vhost-vdpa-blk host device

[Xie Yongji <xieyongji@bytedance.com>]

This commit introduces a new vhost-vdpa block device, which
will set up a vDPA device specified by a "vdpa-dev" parameter,
something like:

qemu-system-x86_64 \
    -device vhost-vdpa-blk-pci,vdpa-dev=/dev/vhost-vdpa-0

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
---
 hw/block/Kconfig                   |   5 +
 hw/block/meson.build               |   1 +
 hw/block/vhost-vdpa-blk.c          | 227 +++++++++++++++++++++++++++++
 hw/virtio/meson.build              |   1 +
 hw/virtio/vhost-vdpa-blk-pci.c     | 101 +++++++++++++
 include/hw/virtio/vhost-vdpa-blk.h |  30 ++++
 6 files changed, 365 insertions(+)
 create mode 100644 hw/block/vhost-vdpa-blk.c
 create mode 100644 hw/virtio/vhost-vdpa-blk-pci.c
 create mode 100644 include/hw/virtio/vhost-vdpa-blk.h

diff --git a/hw/block/Kconfig b/hw/block/Kconfig
index 4fcd152166..4615a2c116 100644
--- a/hw/block/Kconfig
+++ b/hw/block/Kconfig
@@ -41,5 +41,10 @@ config VHOST_USER_BLK
     default y if VIRTIO_PCI
     depends on VIRTIO && VHOST_USER && LINUX
 
+config VHOST_VDPA_BLK
+    bool
+    default y if VIRTIO_PCI
+    depends on VIRTIO && VHOST_VDPA && LINUX
+
 config SWIM
     bool
diff --git a/hw/block/meson.build b/hw/block/meson.build
index 5862bda4cb..98f1fc330a 100644
--- a/hw/block/meson.build
+++ b/hw/block/meson.build
@@ -17,5 +17,6 @@ softmmu_ss.add(when: 'CONFIG_NVME_PCI', if_true: files('nvme.c', 'nvme-ns.c', 'n
 
 specific_ss.add(when: 'CONFIG_VIRTIO_BLK', if_true: files('virtio-blk.c'))
 specific_ss.add(when: 'CONFIG_VHOST_USER_BLK', if_true: files('vhost-blk-common.c', 'vhost-user-blk.c'))
+specific_ss.add(when: 'CONFIG_VHOST_VDPA_BLK', if_true: files('vhost-blk-common.c', 'vhost-vdpa-blk.c'))
 
 subdir('dataplane')
diff --git a/hw/block/vhost-vdpa-blk.c b/hw/block/vhost-vdpa-blk.c
new file mode 100644
index 0000000000..d5cbbbba10
--- /dev/null
+++ b/hw/block/vhost-vdpa-blk.c
@@ -0,0 +1,227 @@
+/*
+ * vhost-vdpa-blk host device
+ *
+ * Copyright (C) 2021 Bytedance Inc. and/or its affiliates. All rights reserved.
+ *
+ * Author:
+ *   Xie Yongji <xieyongji@bytedance.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "qemu/error-report.h"
+#include "qemu/cutils.h"
+#include "hw/qdev-core.h"
+#include "hw/qdev-properties.h"
+#include "hw/qdev-properties-system.h"
+#include "hw/virtio/vhost.h"
+#include "hw/virtio/vhost-vdpa-blk.h"
+#include "hw/virtio/virtio.h"
+#include "hw/virtio/virtio-bus.h"
+#include "hw/virtio/virtio-access.h"
+#include "sysemu/sysemu.h"
+#include "sysemu/runstate.h"
+
+static const int vdpa_feature_bits[] = {
+    VIRTIO_BLK_F_SIZE_MAX,
+    VIRTIO_BLK_F_SEG_MAX,
+    VIRTIO_BLK_F_GEOMETRY,
+    VIRTIO_BLK_F_BLK_SIZE,
+    VIRTIO_BLK_F_TOPOLOGY,
+    VIRTIO_BLK_F_MQ,
+    VIRTIO_BLK_F_RO,
+    VIRTIO_BLK_F_FLUSH,
+    VIRTIO_BLK_F_CONFIG_WCE,
+    VIRTIO_BLK_F_DISCARD,
+    VIRTIO_BLK_F_WRITE_ZEROES,
+    VIRTIO_F_VERSION_1,
+    VIRTIO_RING_F_INDIRECT_DESC,
+    VIRTIO_RING_F_EVENT_IDX,
+    VIRTIO_F_NOTIFY_ON_EMPTY,
+    VHOST_INVALID_FEATURE_BIT
+};
+
+static void vhost_vdpa_blk_set_status(VirtIODevice *vdev, uint8_t status)
+{
+    VHostVdpaBlk *s = VHOST_VDPA_BLK(vdev);
+    VHostBlkCommon *vbc = VHOST_BLK_COMMON(s);
+    bool should_start = virtio_device_started(vdev, status);
+    int ret;
+
+    if (!vdev->vm_running) {
+        should_start = false;
+    }
+
+    if (vbc->dev.started == should_start) {
+        return;
+    }
+
+    if (should_start) {
+        ret = vhost_blk_common_start(vbc);
+        if (ret < 0) {
+            error_report("vhost-vdpa-blk: vhost start failed: %s",
+                         strerror(-ret));
+        }
+    } else {
+        vhost_blk_common_stop(vbc);
+    }
+
+}
+
+static void vhost_vdpa_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq)
+{
+    VHostVdpaBlk *s = VHOST_VDPA_BLK(vdev);
+    VHostBlkCommon *vbc = VHOST_BLK_COMMON(s);
+    int i, ret;
+
+    if (!vdev->start_on_kick) {
+        return;
+    }
+
+    if (vbc->dev.started) {
+        return;
+    }
+
+    ret = vhost_blk_common_start(vbc);
+    if (ret < 0) {
+        error_report("vhost-vdpa-blk: vhost start failed: %s",
+                     strerror(-ret));
+        return;
+    }
+
+    /* Kick right away to begin processing requests already in vring */
+    for (i = 0; i < vbc->dev.nvqs; i++) {
+        VirtQueue *kick_vq = virtio_get_queue(vdev, i);
+
+        if (!virtio_queue_get_desc_addr(vdev, i)) {
+            continue;
+        }
+        event_notifier_set(virtio_queue_get_host_notifier(kick_vq));
+    }
+}
+
+static void vhost_vdpa_blk_device_realize(DeviceState *dev, Error **errp)
+{
+    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    VHostVdpaBlk *s = VHOST_VDPA_BLK(vdev);
+    VHostBlkCommon *vbc = VHOST_BLK_COMMON(s);
+    Error *err = NULL;
+    int ret;
+
+    s->vdpa.device_fd = qemu_open_old(s->vdpa_dev, O_RDWR);
+    if (s->vdpa.device_fd == -1) {
+        error_setg(errp, "vhost-vdpa-blk: open %s failed: %s",
+                   s->vdpa_dev, strerror(errno));
+        return;
+    }
+
+    vhost_blk_common_realize(vbc, vhost_vdpa_blk_handle_output, &err);
+    if (err != NULL) {
+        error_propagate(errp, err);
+        goto blk_err;
+    }
+
+    vbc->vhost_vqs = g_new0(struct vhost_virtqueue, vbc->num_queues);
+    vbc->dev.nvqs = vbc->num_queues;
+    vbc->dev.vqs = vbc->vhost_vqs;
+    vbc->dev.vq_index = 0;
+    vbc->dev.backend_features = 0;
+    vbc->started = false;
+
+    vhost_dev_set_config_notifier(&vbc->dev, &blk_ops);
+
+    ret = vhost_dev_init(&vbc->dev, &s->vdpa, VHOST_BACKEND_TYPE_VDPA, 0);
+    if (ret < 0) {
+        error_setg(errp, "vhost-vdpa-blk: vhost initialization failed: %s",
+                   strerror(-ret));
+        goto init_err;
+    }
+
+    ret = vhost_dev_get_config(&vbc->dev, (uint8_t *)&vbc->blkcfg,
+                               sizeof(struct virtio_blk_config));
+    if (ret < 0) {
+        error_setg(errp, "vhost-vdpa-blk: get block config failed");
+        goto config_err;
+    }
+
+    return;
+config_err:
+    vhost_dev_cleanup(&vbc->dev);
+init_err:
+    vhost_blk_common_unrealize(vbc);
+blk_err:
+    close(s->vdpa.device_fd);
+}
+
+static void vhost_vdpa_blk_device_unrealize(DeviceState *dev)
+{
+    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    VHostVdpaBlk *s = VHOST_VDPA_BLK(dev);
+    VHostBlkCommon *vbc = VHOST_BLK_COMMON(s);
+
+    virtio_set_status(vdev, 0);
+    vhost_dev_cleanup(&vbc->dev);
+    vhost_blk_common_unrealize(vbc);
+    close(s->vdpa.device_fd);
+}
+
+static void vhost_vdpa_blk_instance_init(Object *obj)
+{
+    VHostBlkCommon *vbc = VHOST_BLK_COMMON(obj);
+
+    vbc->feature_bits = vdpa_feature_bits;
+
+    device_add_bootindex_property(obj, &vbc->bootindex, "bootindex",
+                                  "/disk@0,0", DEVICE(obj));
+}
+
+static const VMStateDescription vmstate_vhost_vdpa_blk = {
+    .name = "vhost-vdpa-blk",
+    .minimum_version_id = 1,
+    .version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_VIRTIO_DEVICE,
+        VMSTATE_END_OF_LIST()
+    },
+};
+
+static Property vhost_vdpa_blk_properties[] = {
+    DEFINE_PROP_STRING("vdpa-dev", VHostVdpaBlk, vdpa_dev),
+    DEFINE_PROP_UINT16("num-queues", VHostBlkCommon, num_queues,
+                       VHOST_BLK_AUTO_NUM_QUEUES),
+    DEFINE_PROP_UINT32("queue-size", VHostBlkCommon, queue_size, 256),
+    DEFINE_PROP_BIT("config-wce", VHostBlkCommon, config_wce, 0, true),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void vhost_vdpa_blk_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
+
+    device_class_set_props(dc, vhost_vdpa_blk_properties);
+    dc->vmsd = &vmstate_vhost_vdpa_blk;
+    set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
+    vdc->realize = vhost_vdpa_blk_device_realize;
+    vdc->unrealize = vhost_vdpa_blk_device_unrealize;
+    vdc->set_status = vhost_vdpa_blk_set_status;
+}
+
+static const TypeInfo vhost_vdpa_blk_info = {
+    .name = TYPE_VHOST_VDPA_BLK,
+    .parent = TYPE_VHOST_BLK_COMMON,
+    .instance_size = sizeof(VHostVdpaBlk),
+    .instance_init = vhost_vdpa_blk_instance_init,
+    .class_init = vhost_vdpa_blk_class_init,
+};
+
+static void virtio_register_types(void)
+{
+    type_register_static(&vhost_vdpa_blk_info);
+}
+
+type_init(virtio_register_types)
diff --git a/hw/virtio/meson.build b/hw/virtio/meson.build
index fbff9bc9d4..f02bea65a2 100644
--- a/hw/virtio/meson.build
+++ b/hw/virtio/meson.build
@@ -30,6 +30,7 @@ virtio_pci_ss = ss.source_set()
 virtio_pci_ss.add(when: 'CONFIG_VHOST_VSOCK', if_true: files('vhost-vsock-pci.c'))
 virtio_pci_ss.add(when: 'CONFIG_VHOST_USER_VSOCK', if_true: files('vhost-user-vsock-pci.c'))
 virtio_pci_ss.add(when: 'CONFIG_VHOST_USER_BLK', if_true: files('vhost-user-blk-pci.c'))
+virtio_pci_ss.add(when: 'CONFIG_VHOST_VDPA_BLK', if_true: files('vhost-vdpa-blk-pci.c'))
 virtio_pci_ss.add(when: 'CONFIG_VHOST_USER_INPUT', if_true: files('vhost-user-input-pci.c'))
 virtio_pci_ss.add(when: 'CONFIG_VHOST_USER_SCSI', if_true: files('vhost-user-scsi-pci.c'))
 virtio_pci_ss.add(when: 'CONFIG_VHOST_SCSI', if_true: files('vhost-scsi-pci.c'))
diff --git a/hw/virtio/vhost-vdpa-blk-pci.c b/hw/virtio/vhost-vdpa-blk-pci.c
new file mode 100644
index 0000000000..976c47fb4f
--- /dev/null
+++ b/hw/virtio/vhost-vdpa-blk-pci.c
@@ -0,0 +1,101 @@
+/*
+ * vhost-vdpa-blk PCI Bindings
+ *
+ * Copyright (C) 2021 Bytedance Inc. and/or its affiliates. All rights reserved.
+ *
+ * Author:
+ *   Xie Yongji <xieyongji@bytedance.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "standard-headers/linux/virtio_pci.h"
+#include "hw/virtio/virtio.h"
+#include "hw/virtio/vhost-vdpa-blk.h"
+#include "hw/pci/pci.h"
+#include "hw/qdev-properties.h"
+#include "qapi/error.h"
+#include "qemu/error-report.h"
+#include "qemu/module.h"
+#include "virtio-pci.h"
+#include "qom/object.h"
+
+typedef struct VHostVdpaBlkPCI VHostVdpaBlkPCI;
+
+#define TYPE_VHOST_VDPA_BLK_PCI "vhost-vdpa-blk-pci-base"
+DECLARE_INSTANCE_CHECKER(VHostVdpaBlkPCI, VHOST_VDPA_BLK_PCI,
+                         TYPE_VHOST_VDPA_BLK_PCI)
+
+struct VHostVdpaBlkPCI {
+    VirtIOPCIProxy parent_obj;
+    VHostVdpaBlk vdev;
+};
+
+static Property vhost_vdpa_blk_pci_properties[] = {
+    DEFINE_PROP_UINT32("class", VirtIOPCIProxy, class_code, 0),
+    DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors,
+                       DEV_NVECTORS_UNSPECIFIED),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void vhost_vdpa_blk_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp)
+{
+    VHostVdpaBlkPCI *dev = VHOST_VDPA_BLK_PCI(vpci_dev);
+    DeviceState *vdev = DEVICE(&dev->vdev);
+    VHostBlkCommon *vbc = VHOST_BLK_COMMON(&dev->vdev);
+
+    if (vbc->num_queues == VHOST_BLK_AUTO_NUM_QUEUES) {
+        vbc->num_queues = virtio_pci_optimal_num_queues(0);
+    }
+
+    if (vpci_dev->nvectors == DEV_NVECTORS_UNSPECIFIED) {
+        vpci_dev->nvectors = vbc->num_queues + 1;
+    }
+
+    qdev_realize(vdev, BUS(&vpci_dev->bus), errp);
+}
+
+static void vhost_vdpa_blk_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);
+
+    set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
+    device_class_set_props(dc, vhost_vdpa_blk_pci_properties);
+    k->realize = vhost_vdpa_blk_pci_realize;
+    pcidev_k->vendor_id = PCI_VENDOR_ID_REDHAT_QUMRANET;
+    pcidev_k->device_id = PCI_DEVICE_ID_VIRTIO_BLOCK;
+    pcidev_k->revision = VIRTIO_PCI_ABI_VERSION;
+    pcidev_k->class_id = PCI_CLASS_STORAGE_SCSI;
+}
+
+static void vhost_vdpa_blk_pci_instance_init(Object *obj)
+{
+    VHostVdpaBlkPCI *dev = VHOST_VDPA_BLK_PCI(obj);
+
+    virtio_instance_init_common(obj, &dev->vdev, sizeof(dev->vdev),
+                                TYPE_VHOST_VDPA_BLK);
+    object_property_add_alias(obj, "bootindex", OBJECT(&dev->vdev),
+                              "bootindex");
+}
+
+static const VirtioPCIDeviceTypeInfo vhost_vdpa_blk_pci_info = {
+    .base_name               = TYPE_VHOST_VDPA_BLK_PCI,
+    .generic_name            = "vhost-vdpa-blk-pci",
+    .transitional_name       = "vhost-vdpa-blk-pci-transitional",
+    .non_transitional_name   = "vhost-vdpa-blk-pci-non-transitional",
+    .instance_size  = sizeof(VHostVdpaBlkPCI),
+    .instance_init  = vhost_vdpa_blk_pci_instance_init,
+    .class_init     = vhost_vdpa_blk_pci_class_init,
+};
+
+static void vhost_vdpa_blk_pci_register(void)
+{
+    virtio_pci_types_register(&vhost_vdpa_blk_pci_info);
+}
+
+type_init(vhost_vdpa_blk_pci_register)
diff --git a/include/hw/virtio/vhost-vdpa-blk.h b/include/hw/virtio/vhost-vdpa-blk.h
new file mode 100644
index 0000000000..80712f6dae
--- /dev/null
+++ b/include/hw/virtio/vhost-vdpa-blk.h
@@ -0,0 +1,30 @@
+/*
+ * vhost-vdpa-blk host device
+ *
+ * Copyright (C) 2021 Bytedance Inc. and/or its affiliates. All rights reserved.
+ *
+ * Author:
+ *   Xie Yongji <xieyongji@bytedance.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#ifndef VHOST_VDPA_BLK_H
+#define VHOST_VDPA_BLK_H
+
+#include "hw/virtio/vhost-vdpa.h"
+#include "hw/virtio/vhost-blk-common.h"
+#include "qom/object.h"
+
+#define TYPE_VHOST_VDPA_BLK "vhost-vdpa-blk"
+OBJECT_DECLARE_SIMPLE_TYPE(VHostVdpaBlk, VHOST_VDPA_BLK)
+
+struct VHostVdpaBlk {
+    VHostBlkCommon parent_obj;
+    char *vdpa_dev;
+    struct vhost_vdpa vdpa;
+};
+
+#endif
-- 
2.25.1