By making use of libvhost-user, block device drive can be shared to
the connected vhost-user client. Only one client can connect to the
server one time.
Since vhost-user-server needs a block drive to be created first, delay
the creation of this object.
Signed-off-by: Coiby Xu <coiby...@gmail.com>
---
block/Makefile.objs | 1 +
block/export/vhost-user-blk-server.c | 716 +++++++++++++++++++++++++++
block/export/vhost-user-blk-server.h | 34 ++
softmmu/vl.c | 4 +
4 files changed, 755 insertions(+)
create mode 100644 block/export/vhost-user-blk-server.c
create mode 100644 block/export/vhost-user-blk-server.h
diff --git a/block/Makefile.objs b/block/Makefile.objs
index 3635b6b4c1..0eb7eff470 100644
--- a/block/Makefile.objs
+++ b/block/Makefile.objs
@@ -24,6 +24,7 @@ block-obj-y += throttle-groups.o
block-obj-$(CONFIG_LINUX) += nvme.o
block-obj-y += nbd.o
+block-obj-$(CONFIG_LINUX) += export/vhost-user-blk-server.o
../contrib/libvhost-user/libvhost-user.o
block-obj-$(CONFIG_SHEEPDOG) += sheepdog.o
block-obj-$(CONFIG_LIBISCSI) += iscsi.o
block-obj-$(if $(CONFIG_LIBISCSI),y,n) += iscsi-opts.o
diff --git a/block/export/vhost-user-blk-server.c
b/block/export/vhost-user-blk-server.c
new file mode 100644
index 0000000000..a9dec0625f
--- /dev/null
+++ b/block/export/vhost-user-blk-server.c
@@ -0,0 +1,716 @@
+/*
+ * Sharing QEMU block devices via vhost-user protocal
+ *
+ * Author: Coiby Xu <coiby...@gmail.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later. See the COPYING file in the top-level directory.
+ */
+#include "qemu/osdep.h"
+#include "block/block.h"
+#include "vhost-user-blk-server.h"
+#include "qapi/error.h"
+#include "qom/object_interfaces.h"
+#include "sysemu/block-backend.h"
+
+enum {
+ VHOST_USER_BLK_MAX_QUEUES = 1,
+};
+struct virtio_blk_inhdr {
+ unsigned char status;
+};
+
+static QTAILQ_HEAD(, VuBlockDev) vu_block_devs =
+ QTAILQ_HEAD_INITIALIZER(vu_block_devs);
+
+
+typedef struct VuBlockReq {
+ VuVirtqElement *elem;
+ int64_t sector_num;
+ size_t size;
+ struct virtio_blk_inhdr *in;
+ struct virtio_blk_outhdr out;
+ VuServer *server;
+ struct VuVirtq *vq;
+} VuBlockReq;
+
+
+static void vu_block_req_complete(VuBlockReq *req)
+{
+ VuDev *vu_dev = &req->server->vu_dev;
+
+ /* IO size with 1 extra status byte */
+ vu_queue_push(vu_dev, req->vq, req->elem, req->size + 1);
+ vu_queue_notify(vu_dev, req->vq);
+
+ if (req->elem) {
+ free(req->elem);
+ }
+
+ g_free(req);
+}
+
+static VuBlockDev *get_vu_block_device_by_server(VuServer *server)
+{
+ return container_of(server, VuBlockDev, vu_server);
+}
+
+static int coroutine_fn
+vu_block_discard_write_zeroes(VuBlockReq *req, struct iovec *iov,
+ uint32_t iovcnt, uint32_t type)
+{
+ struct virtio_blk_discard_write_zeroes desc;
+ ssize_t size = iov_to_buf(iov, iovcnt, 0, &desc, sizeof(desc));
+ if (unlikely(size != sizeof(desc))) {
+ error_report("Invalid size %ld, expect %ld", size, sizeof(desc));
+ return -EINVAL;
+ }
+
+ VuBlockDev *vdev_blk = get_vu_block_device_by_server(req->server);
+ uint64_t range[2] = { le64toh(desc.sector) << 9,
+ le32toh(desc.num_sectors) << 9 };
+ if (type == VIRTIO_BLK_T_DISCARD) {
+ if (blk_co_pdiscard(vdev_blk->backend, range[0], range[1]) == 0) {
+ return 0;
+ }
+ } else if (type == VIRTIO_BLK_T_WRITE_ZEROES) {
+ if (blk_co_pwrite_zeroes(vdev_blk->backend,
+ range[0], range[1], 0) == 0) {
+ return 0;
+ }
+ }
+
+ return -EINVAL;
+}
+
+
+static void coroutine_fn vu_block_flush(VuBlockReq *req)
+{
+ VuBlockDev *vdev_blk = get_vu_block_device_by_server(req->server);
+ BlockBackend *backend = vdev_blk->backend;
+ blk_co_flush(backend);
+}
+
+
+struct req_data {
+ VuServer *server;
+ VuVirtq *vq;
+ VuVirtqElement *elem;
+};
+
+static void coroutine_fn vu_block_virtio_process_req(void *opaque)
+{
+ struct req_data *data = opaque;
+ VuServer *server = data->server;
+ VuVirtq *vq = data->vq;
+ VuVirtqElement *elem = data->elem;
+ uint32_t type;
+ VuBlockReq *req;
+
+ VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+ BlockBackend *backend = vdev_blk->backend;
+
+ struct iovec *in_iov = elem->in_sg;
+ struct iovec *out_iov = elem->out_sg;
+ unsigned in_num = elem->in_num;
+ unsigned out_num = elem->out_num;
+ /* refer to hw/block/virtio_blk.c */
+ if (elem->out_num < 1 || elem->in_num < 1) {
+ error_report("virtio-blk request missing headers");
+ free(elem);
+ return;
+ }
+
+ req = g_new0(VuBlockReq, 1);
+ req->server = server;
+ req->vq = vq;
+ req->elem = elem;
+
+ if (unlikely(iov_to_buf(out_iov, out_num, 0, &req->out,
+ sizeof(req->out)) != sizeof(req->out))) {
+ error_report("virtio-blk request outhdr too short");
+ goto err;
+ }
+
+ iov_discard_front(&out_iov, &out_num, sizeof(req->out));
+
+ if (in_iov[in_num - 1].iov_len < sizeof(struct virtio_blk_inhdr)) {
+ error_report("virtio-blk request inhdr too short");
+ goto err;
+ }
+
+ /* We always touch the last byte, so just see how big in_iov is. */
+ req->in = (void *)in_iov[in_num - 1].iov_base
+ + in_iov[in_num - 1].iov_len
+ - sizeof(struct virtio_blk_inhdr);
+ iov_discard_back(in_iov, &in_num, sizeof(struct virtio_blk_inhdr));
+
+
+ type = le32toh(req->out.type);
+ switch (type & ~VIRTIO_BLK_T_BARRIER) {
+ case VIRTIO_BLK_T_IN:
+ case VIRTIO_BLK_T_OUT: {
+ ssize_t ret = 0;
+ bool is_write = type & VIRTIO_BLK_T_OUT;
+ req->sector_num = le64toh(req->out.sector);
+
+ int64_t offset = req->sector_num * vdev_blk->blk_size;
+ QEMUIOVector *qiov = g_new0(QEMUIOVector, 1);
+ if (is_write) {
+ qemu_iovec_init_external(qiov, out_iov, out_num);
+ ret = blk_co_pwritev(backend, offset, qiov->size,
+ qiov, 0);
+ } else {
+ qemu_iovec_init_external(qiov, in_iov, in_num);
+ ret = blk_co_preadv(backend, offset, qiov->size,
+ qiov, 0);
+ }
+ if (ret >= 0) {
+ req->in->status = VIRTIO_BLK_S_OK;
+ } else {
+ req->in->status = VIRTIO_BLK_S_IOERR;
+ }
+ g_free(qiov);
+ break;
+ }
+ case VIRTIO_BLK_T_FLUSH:
+ vu_block_flush(req);
+ req->in->status = VIRTIO_BLK_S_OK;
+ break;
+ case VIRTIO_BLK_T_GET_ID: {
+ size_t size = MIN(iov_size(&elem->in_sg[0], in_num),
+ VIRTIO_BLK_ID_BYTES);
+ snprintf(elem->in_sg[0].iov_base, size, "%s", "vhost_user_blk_server");
+ req->in->status = VIRTIO_BLK_S_OK;
+ req->size = elem->in_sg[0].iov_len;
+ break;
+ }
+ case VIRTIO_BLK_T_DISCARD:
+ case VIRTIO_BLK_T_WRITE_ZEROES: {
+ int rc;
+ rc = vu_block_discard_write_zeroes(req, &elem->out_sg[1],
+ out_num, type);
+ if (rc == 0) {
+ req->in->status = VIRTIO_BLK_S_OK;
+ } else {
+ req->in->status = VIRTIO_BLK_S_IOERR;
+ }
+ break;
+ }
+ default:
+ req->in->status = VIRTIO_BLK_S_UNSUPP;
+ break;
+ }
+
+ vu_block_req_complete(req);
+ return;
+
+err:
+ free(elem);
+ g_free(req);
+ return;
+}
+
+
+
+static void vu_block_process_vq(VuDev *vu_dev, int idx)
+{
+ VuServer *server;
+ VuVirtq *vq;
+
+ server = container_of(vu_dev, VuServer, vu_dev);
+ assert(server);
+
+ vq = vu_get_queue(vu_dev, idx);
+ assert(vq);
+ VuVirtqElement *elem;
+ while (1) {
+ elem = vu_queue_pop(vu_dev, vq, sizeof(VuVirtqElement) +
+ sizeof(VuBlockReq));
+ if (elem) {
+ struct req_data req_data = {
+ .server = server,
+ .vq = vq,
+ .elem = elem
+ };
+ Coroutine *co = qemu_coroutine_create(vu_block_virtio_process_req,
+ &req_data);
+ aio_co_enter(server->ioc->ctx, co);
+ } else {
+ break;
+ }
+ }
+}
+
+static void vu_block_queue_set_started(VuDev *vu_dev, int idx, bool started)
+{
+ VuVirtq *vq;
+
+ assert(vu_dev);
+
+ vq = vu_get_queue(vu_dev, idx);
+ vu_set_queue_handler(vu_dev, vq, started ? vu_block_process_vq : NULL);
+}
+
+static uint64_t vu_block_get_features(VuDev *dev)
+{
+ uint64_t features;
+ VuServer *server = container_of(dev, VuServer, vu_dev);
+ VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+ features = 1ull << VIRTIO_BLK_F_SIZE_MAX |
+ 1ull << VIRTIO_BLK_F_SEG_MAX |
+ 1ull << VIRTIO_BLK_F_TOPOLOGY |
+ 1ull << VIRTIO_BLK_F_BLK_SIZE |
+ 1ull << VIRTIO_BLK_F_FLUSH |
+ 1ull << VIRTIO_BLK_F_DISCARD |
+ 1ull << VIRTIO_BLK_F_WRITE_ZEROES |
+ 1ull << VIRTIO_BLK_F_CONFIG_WCE |
+ 1ull << VIRTIO_F_VERSION_1 |
+ 1ull << VIRTIO_RING_F_INDIRECT_DESC |
+ 1ull << VIRTIO_RING_F_EVENT_IDX |
+ 1ull << VHOST_USER_F_PROTOCOL_FEATURES;
+
+ if (!vdev_blk->writable) {
+ features |= 1ull << VIRTIO_BLK_F_RO;
+ }
+
+ return features;
+}
+
+static uint64_t vu_block_get_protocol_features(VuDev *dev)
+{
+ return 1ull << VHOST_USER_PROTOCOL_F_CONFIG |
+ 1ull << VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD;
+}
+
+static int
+vu_block_get_config(VuDev *vu_dev, uint8_t *config, uint32_t len)
+{
+ VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+ VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+ memcpy(config, &vdev_blk->blkcfg, len);
+
+ return 0;
+}
+
+static int
+vu_block_set_config(VuDev *vu_dev, const uint8_t *data,
+ uint32_t offset, uint32_t size, uint32_t flags)
+{
+ VuServer *server = container_of(vu_dev, VuServer, vu_dev);
+ VuBlockDev *vdev_blk = get_vu_block_device_by_server(server);
+ uint8_t wce;
+
+ /* don't support live migration */
+ if (flags != VHOST_SET_CONFIG_TYPE_MASTER) {
+ return -EINVAL;
+ }
+
+
+ if (offset != offsetof(struct virtio_blk_config, wce) ||
+ size != 1) {
+ return -EINVAL;
+ }
+
+ wce = *data;
+ if (wce == vdev_blk->blkcfg.wce) {
+ /* Do nothing as same with old configuration */
+ return 0;
+ }
+
+ vdev_blk->blkcfg.wce = wce;
+ blk_set_enable_write_cache(vdev_blk->backend, wce);
+ return 0;
+}
+
+
+/*
+ * When the client disconnects, it sends a VHOST_USER_NONE request
+ * and vu_process_message will simple call exit which cause the VM
+ * to exit abruptly.
+ * To avoid this issue, process VHOST_USER_NONE request ahead
+ * of vu_process_message.
+ *
+ */
+static int vu_block_process_msg(VuDev *dev, VhostUserMsg *vmsg, int *do_reply)
+{
+ if (vmsg->request == VHOST_USER_NONE) {
+ dev->panic(dev, "disconnect");
+ return true;
+ }
+ return false;
+}
+
+
+static const VuDevIface vu_block_iface = {
+ .get_features = vu_block_get_features,
+ .queue_set_started = vu_block_queue_set_started,
+ .get_protocol_features = vu_block_get_protocol_features,
+ .get_config = vu_block_get_config,
+ .set_config = vu_block_set_config,
+ .process_msg = vu_block_process_msg,
+};
+
+static void blk_aio_attached(AioContext *ctx, void *opaque)
+{
+ VuBlockDev *vub_dev = opaque;
+ aio_context_acquire(ctx);
+ vhost_user_server_set_aio_context(ctx, &vub_dev->vu_server);
+ aio_context_release(ctx);
+}
+
+static void blk_aio_detach(void *opaque)
+{
+ VuBlockDev *vub_dev = opaque;
+ AioContext *ctx = vub_dev->vu_server.ctx;
+ aio_context_acquire(ctx);
+ vhost_user_server_set_aio_context(NULL, &vub_dev->vu_server);
+ aio_context_release(ctx);
+}
+
+static void vu_block_free(VuBlockDev *vu_block_dev)
+{
+ if (!vu_block_dev) {
+ return;
+ }
+
+ if (vu_block_dev->backend) {
+ blk_remove_aio_context_notifier(vu_block_dev->backend,
blk_aio_attached,
+ blk_aio_detach, vu_block_dev);
+ }
+
+ blk_unref(vu_block_dev->backend);
+
+ if (vu_block_dev->next.tqe_circ.tql_prev) {
+ /*
+ * remove vu_block_device from the list
+ *
+ * if vu_block_dev->next.tqe_circ.tql_prev = null,
+ * vu_block_dev hasn't been inserted into the queue and
+ * vu_block_free is called by obj->instance_finalize.
+ */
+ QTAILQ_REMOVE(&vu_block_devs, vu_block_dev, next);
+ }
+}
+
+static void
+vu_block_initialize_config(BlockDriverState *bs,
+ struct virtio_blk_config *config, uint32_t blk_size)
+{
+ config->capacity = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
+ config->blk_size = blk_size;
+ config->size_max = 0;
+ config->seg_max = 128 - 2;
+ config->min_io_size = 1;
+ config->opt_io_size = 1;
+ config->num_queues = VHOST_USER_BLK_MAX_QUEUES;
+ config->max_discard_sectors = 32768;
+ config->max_discard_seg = 1;
+ config->discard_sector_alignment = config->blk_size >> 9;
+ config->max_write_zeroes_sectors = 32768;
+ config->max_write_zeroes_seg = 1;
+}
+
+
+static VuBlockDev *vu_block_init(VuBlockDev *vu_block_device, Error **errp)
+{
+
+ BlockBackend *blk;
+ Error *local_error = NULL;
+ const char *node_name = vu_block_device->node_name;
+ bool writable = vu_block_device->writable;
+ /*
+ * Don't allow resize while the vhost user server is running,
+ * otherwise we don't care what happens with the node.
+ */
+ uint64_t perm = BLK_PERM_CONSISTENT_READ;
+ int ret;
+
+ AioContext *ctx;
+
+ BlockDriverState *bs = bdrv_lookup_bs(node_name, node_name, &local_error);
+
+ if (!bs) {
+ error_propagate(errp, local_error);
+ return NULL;
+ }
+
+ if (bdrv_is_read_only(bs)) {
+ writable = false;
+ }
+
+ if (writable) {
+ perm |= BLK_PERM_WRITE;
+ }
+
+ ctx = bdrv_get_aio_context(bs);
+ aio_context_acquire(ctx);
+ bdrv_invalidate_cache(bs, NULL);
+ aio_context_release(ctx);
+
+ blk = blk_new(bdrv_get_aio_context(bs), perm,
+ BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED |
+ BLK_PERM_WRITE | BLK_PERM_GRAPH_MOD);
+ ret = blk_insert_bs(blk, bs, errp);
+
+ if (ret < 0) {
+ goto fail;
+ }
+
+ blk_set_enable_write_cache(blk, false);
+
+ blk_set_allow_aio_context_change(blk, true);
+
+ vu_block_device->blkcfg.wce = 0;
+ vu_block_device->backend = blk;
+ if (!vu_block_device->blk_size) {
+ vu_block_device->blk_size = BDRV_SECTOR_SIZE;
+ }
+ vu_block_device->blkcfg.blk_size = vu_block_device->blk_size;
+ blk_set_guest_block_size(blk, vu_block_device->blk_size);
+ vu_block_initialize_config(bs, &vu_block_device->blkcfg,
+ vu_block_device->blk_size);
+ return vu_block_device;
+
+fail:
+ blk_unref(blk);
+ return NULL;
+}
+
+static void vhost_user_blk_server_free(VuBlockDev *vu_block_device)
+{
+ if (!vu_block_device) {
+ return;
+ }
+ vhost_user_server_stop(&vu_block_device->vu_server);
+ vu_block_free(vu_block_device);
+
+}
+
+/*
+ * A exported drive can serve multiple multiple clients simutateously,
+ * thus no need to export the same drive twice.
+ *
+ */
+static VuBlockDev *vu_block_dev_find(const char *node_name)
+{
+ VuBlockDev *vu_block_device;
+ QTAILQ_FOREACH(vu_block_device, &vu_block_devs, next) {
+ if (strcmp(node_name, vu_block_device->node_name) == 0) {
+ return vu_block_device;
+ }
+ }
+
+ return NULL;
+}
+
+
+static VuBlockDev
+*vu_block_dev_find_by_unix_socket(const char *unix_socket)
+{
+ VuBlockDev *vu_block_device;
+ QTAILQ_FOREACH(vu_block_device, &vu_block_devs, next) {
+ if (strcmp(unix_socket, vu_block_device->addr->u.q_unix.path) == 0) {
+ return vu_block_device;
+ }
+ }
+
+ return NULL;
+}
+
+
+static void vhost_user_blk_server_start(VuBlockDev *vu_block_device,
+ Error **errp)
+{
+
+ const char *name = vu_block_device->node_name;
+ SocketAddress *addr = vu_block_device->addr;
+ char *unix_socket = vu_block_device->addr->u.q_unix.path;
+
+ if (vu_block_dev_find(name)) {
+ error_setg(errp, "Vhost-user-blk server with node-name '%s' "
+ "has already been started",
+ name);
+ return;
+ }
+
+ if (vu_block_dev_find_by_unix_socket(unix_socket)) {
+ error_setg(errp, "Vhost-user-blk server with with socket_path '%s' "
+ "has already been started", unix_socket);
+ return;
+ }
+
+ if (!vu_block_init(vu_block_device, errp)) {
+ return;
+ }
+
+
+ AioContext *ctx = bdrv_get_aio_context(blk_bs(vu_block_device->backend));
+
+ if (!vhost_user_server_start(VHOST_USER_BLK_MAX_QUEUES, addr, ctx,
+ &vu_block_device->vu_server,
+ NULL, &vu_block_iface,
+ errp)) {
+ goto error;
+ }
+
+ QTAILQ_INSERT_TAIL(&vu_block_devs, vu_block_device, next);
+ blk_add_aio_context_notifier(vu_block_device->backend, blk_aio_attached,
+ blk_aio_detach, vu_block_device);
+ return;
+
+ error:
+ vu_block_free(vu_block_device);
+}
+
+static void vu_set_node_name(Object *obj, const char *value, Error **errp)
+{
+ VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+
+ if (vus->node_name) {
+ error_setg(errp, "evdev property already set");
+ return;
+ }
+
+ vus->node_name = g_strdup(value);
+}
+
+static char *vu_get_node_name(Object *obj, Error **errp)
+{
+ VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+ return g_strdup(vus->node_name);
+}
+
+
+static void vu_set_unix_socket(Object *obj, const char *value,
+ Error **errp)
+{
+ VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+
+ if (vus->addr) {
+ error_setg(errp, "unix_socket property already set");
+ return;
+ }
+
+ SocketAddress *addr = g_new0(SocketAddress, 1);
+ addr->type = SOCKET_ADDRESS_TYPE_UNIX;
+ addr->u.q_unix.path = g_strdup(value);
+ vus->addr = addr;
+}
+
+static char *vu_get_unix_socket(Object *obj, Error **errp)
+{
+ VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+ return g_strdup(vus->addr->u.q_unix.path);
+}
+
+static bool vu_get_block_writable(Object *obj, Error **errp)
+{
+ VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+ return vus->writable;
+}
+
+static void vu_set_block_writable(Object *obj, bool value, Error **errp)
+{
+ VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+
+ vus->writable = value;
+}
+
+static void vu_get_blk_size(Object *obj, Visitor *v, const char *name,
+ void *opaque, Error **errp)
+{
+ VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+ uint32_t value = vus->blk_size;
+
+ visit_type_uint32(v, name, &value, errp);
+}
+
+static void vu_set_blk_size(Object *obj, Visitor *v, const char *name,
+ void *opaque, Error **errp)
+{
+ VuBlockDev *vus = VHOST_USER_BLK_SERVER(obj);
+
+ Error *local_err = NULL;
+ uint32_t value;
+
+ visit_type_uint32(v, name, &value, &local_err);
+ if (local_err) {
+ goto out;
+ }
+ if (value != BDRV_SECTOR_SIZE && value != 4096) {
+ error_setg(&local_err,
+ "Property '%s.%s' can only take value 512 or 4096",
+ object_get_typename(obj), name);
+ goto out;
+ }
+
+ vus->blk_size = value;
+
+out:
+ error_propagate(errp, local_err);
+ vus->blk_size = value;
+}
+
+
+static void vhost_user_blk_server_instance_finalize(Object *obj)
+{
+ VuBlockDev *vub = VHOST_USER_BLK_SERVER(obj);
+
+ vhost_user_blk_server_free(vub);
+}
+
+static void vhost_user_blk_server_complete(UserCreatable *obj, Error **errp)
+{
+ Error *local_error = NULL;
+ VuBlockDev *vub = VHOST_USER_BLK_SERVER(obj);
+
+ vhost_user_blk_server_start(vub, &local_error);
+
+ if (local_error) {
+ error_propagate(errp, local_error);
+ return;
+ }
+}
+
+static void vhost_user_blk_server_class_init(ObjectClass *klass,
+ void *class_data)
+{
+ UserCreatableClass *ucc = USER_CREATABLE_CLASS(klass);
+ ucc->complete = vhost_user_blk_server_complete;
+
+ object_class_property_add_bool(klass, "writable",
+ vu_get_block_writable,
+ vu_set_block_writable);
+
+ object_class_property_add_str(klass, "node-name",
+ vu_get_node_name,
+ vu_set_node_name);
+
+ object_class_property_add_str(klass, "unix-socket",
+ vu_get_unix_socket,
+ vu_set_unix_socket);
+
+ object_class_property_add(klass, "blk-size", "uint32",
+ vu_get_blk_size, vu_set_blk_size,
+ NULL, NULL);
+}
+
+static const TypeInfo vhost_user_blk_server_info = {
+ .name = TYPE_VHOST_USER_BLK_SERVER,
+ .parent = TYPE_OBJECT,
+ .instance_size = sizeof(VuBlockDev),
+ .instance_finalize = vhost_user_blk_server_instance_finalize,
+ .class_init = vhost_user_blk_server_class_init,
+ .interfaces = (InterfaceInfo[]) {
+ {TYPE_USER_CREATABLE},
+ {}
+ },
+};
+
+static void vhost_user_blk_server_register_types(void)
+{
+ type_register_static(&vhost_user_blk_server_info);
+}
+
+type_init(vhost_user_blk_server_register_types)
diff --git a/block/export/vhost-user-blk-server.h
b/block/export/vhost-user-blk-server.h
new file mode 100644
index 0000000000..6a393ed49d
--- /dev/null
+++ b/block/export/vhost-user-blk-server.h
@@ -0,0 +1,34 @@
+/*
+ * Sharing QEMU block devices via vhost-user protocal
+ *
+ * Author: Coiby Xu <coiby...@gmail.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later. See the COPYING file in the top-level directory.
+ */
+
+#ifndef VHOST_USER_BLK_SERVER_H
+#define VHOST_USER_BLK_SERVER_H
+#include "util/vhost-user-server.h"
+
+typedef struct VuBlockDev VuBlockDev;
+#define TYPE_VHOST_USER_BLK_SERVER "vhost-user-blk-server"
+#define VHOST_USER_BLK_SERVER(obj) \
+ OBJECT_CHECK(VuBlockDev, obj, TYPE_VHOST_USER_BLK_SERVER)
+
+/* vhost user block device */
+struct VuBlockDev {
+ Object parent_obj;
+ char *node_name;
+ SocketAddress *addr;
+ AioContext *ctx;
+ VuServer vu_server;
+ uint32_t blk_size;
+ BlockBackend *backend;
+ QIOChannelSocket *sioc;
+ QTAILQ_ENTRY(VuBlockDev) next;
+ struct virtio_blk_config blkcfg;
+ bool writable;
+};
+
+#endif /* VHOST_USER_BLK_SERVER_H */
diff --git a/softmmu/vl.c b/softmmu/vl.c
index ae5451bc23..e4549871e1 100644
--- a/softmmu/vl.c
+++ b/softmmu/vl.c
@@ -2520,6 +2520,10 @@ static bool object_create_initial(const char *type,
QemuOpts *opts)
}
#endif
+ /* Reason: vhost-user-blk-server property "node-name" */
+ if (g_str_equal(type, "vhost-user-blk-server")) {
+ return false;
+ }
/*
* Reason: filter-* property "netdev" etc.
*/
--
2.26.2
