Re: [PATCH v13 00/13] Introduce VDUSE - vDPA Device in Userspace

Liuxiangdong
2021-10-11T07:32:57Z

Hi, Yongji.

I tried vduse with null-blk:

$ qemu-storage-daemon \
--chardev socket,id=charmonitor,path=/tmp/qmp.sock,server,nowait \
--monitor chardev=charmonitor \
--blockdev
driver=host_device,cache.direct=on,aio=native,filename=/dev/nullb0,node-name=disk0
\
--export
type=vduse-blk,id=test,node-name=disk0,writable=on,name=vduse-null,num-queues=16,queue-size=128

The qemu-storage-daemon is yours
(https://github.com/bytedance/qemu/tree/vduse)

And then, how can we use this vduse-null (dev/vduse/vduse-null) in vm(QEMU)?

Because qemu-storage-daemon open this vduse-null in vduse_dev_init(),
all the operations which open this dev
will report "failed to open '/dev/vduse/vduse-null': Device or resource
busy".

Or something I understood wrong?

Thanks!
Xiangdong Liu