Hello,
This series added support for multi-path I/O with multi-controllers and
namespace sharing. By supporting these features, we can test Linux
kernel mpath(multi-path) code with this NVMe device.
Patches from the first to third added multi-controller support in a NVM
subsystem by adding a mpath.ctrl parameter to nvme device. The rest of
the patches added namespace sharing support in a NVM subsystem with two
or more controllers by adding mpath.ns parameter to nvme-ns device.
Multi-path enabled in kernel with this series for two controllers with a
namespace:
root@vm:~/work# nvme list -v
NVM Express Subsystems
Subsystem Subsystem-NQN
Controllers
----------------
------------------------------------------------------------------------------------------------
----------------
nvme-subsys0 nqn.2019-08.org.qemu:serial
nvme0, nvme1
NVM Express Controllers
Device SN MN FR
TxPort Address Subsystem Namespaces
-------- -------------------- ----------------------------------------
-------- ------ -------------- ------------ ----------------
nvme0 serial QEMU NVMe Ctrl 1.0
pcie 0000:01:00.0 nvme-subsys0 nvme0n1
nvme1 serial QEMU NVMe Ctrl 1.0
pcie 0000:02:00.0 nvme-subsys0 nvme0n1
NVM Express Namespaces
Device NSID Usage Format Controllers
------------ -------- -------------------------- ----------------
----------------
nvme0n1 1 268.44 MB / 268.44 MB 512 B + 0 B nvme0, nvme1
The reason why I put 'RFC' tag to this series is mostly about the last
patch "hw/block/nvme: add namespace sharing param for mpath". It seems
like QEMU block backing device does not support to be shared among two
or more -device(s). It means that we just can't give same drive=
property to multiple nvme-ns devices. This patch has just let -device
maps to -drive one-to-one(1:1), but if namespae sharing is detected and
setup by the host kernel, then a single block device will be selected
for the NVM subsystem. I'm not sure this is a good start for this
feature, so I put the RFC tag here.
Please kindly review!
Thanks,
Minwoo Im (5):
hw/block/nvme: add controller id parameter
nvme: add CMIC enum value for Identify Controller
hw/block/nvme: add multi-controller param for mpath
nvme: add NMIC enum value for Identify Namespace
hw/block/nvme: add namespace sharing param for mpath
hw/block/nvme-ns.c | 14 ++++++++++++--
hw/block/nvme-ns.h | 2 ++
hw/block/nvme.c | 26 ++++++++++++++++++++++++++
hw/block/nvme.h | 2 ++
include/block/nvme.h | 8 ++++++++
5 files changed, 50 insertions(+), 2 deletions(-)
--
2.17.1
