Hello,
This patch series introduces NVMe subsystem device to support multi-path
I/O in NVMe device model. Two use-cases are supported along with this
patch: Multi-controller, Namespace Sharing.
V1 RFC has been discussed with Klaus and Keith, I really appreciate them
for this patch series to have proper direction [1].
This patch series contains few start-up refactoring pathces from the
first to fifth patches to make nvme-ns device not to rely on the nvme
controller always. Because nvme-ns shall be able to be mapped to the
subsystem level, not a single controller level so that it should provide
generic initialization code: nvme_ns_setup() with NvmeCtrl. To do that,
the first five patches are to remove the NvmeCtrl * instance argument
from the nvme_ns_setup(). I'd be happy if they are picked!
For controller and namespace devices, 'subsys' property has been
introduced to map them to a subsystem. If multi-controller needed, we
can specify 'subsys' to controllers the same.
For namespace deivice, if 'subsys' is not given just like it was, it
will have to be provided with 'bus' parameter to specify a nvme
controller device to attach, it means, they are mutual-exlusive. To
share a namespace between or among controllers, then nvme-ns should have
'subsys' property to a single nvme subsystem instance. To make a
namespace private one, then we need to specify 'bus' property rather
than the 'subsys'.
Of course, this series does not require any updates for the run command
for the previos users.
Plase refer the following example with nvme-cli output:
QEMU Run:
-device nvme-subsys,id=subsys0 \
-device nvme,serial=foo,id=nvme0,subsys=subsys0 \
-device nvme,serial=bar,id=nvme1,subsys=subsys0 \
-device nvme,serial=baz,id=nvme2,subsys=subsys0 \
-device nvme-ns,id=ns1,drive=drv10,nsid=1,subsys=subsys0 \
-device nvme-ns,id=ns2,drive=drv11,nsid=2,bus=nvme2 \
\
-device nvme,serial=qux,id=nvme3 \
-device nvme-ns,id=ns3,drive=drv12,nsid=3,bus=nvme3
nvme-cli:
root@vm:~/work# nvme list -v
NVM Express Subsystems
Subsystem Subsystem-NQN
Controllers
----------------
------------------------------------------------------------------------------------------------
----------------
nvme-subsys1 nqn.2019-08.org.qemu:subsys0
nvme0, nvme1, nvme2
nvme-subsys3 nqn.2019-08.org.qemu:qux
nvme3
NVM Express Controllers
Device SN MN FR
TxPort Address Subsystem Namespaces
-------- -------------------- ----------------------------------------
-------- ------ -------------- ------------ ----------------
nvme0 foo QEMU NVMe Ctrl 1.0
pcie 0000:00:06.0 nvme-subsys1 nvme1n1
nvme1 bar QEMU NVMe Ctrl 1.0
pcie 0000:00:07.0 nvme-subsys1 nvme1n1
nvme2 baz QEMU NVMe Ctrl 1.0
pcie 0000:00:08.0 nvme-subsys1 nvme1n1, nvme1n2
nvme3 qux QEMU NVMe Ctrl 1.0
pcie 0000:00:09.0 nvme-subsys3
NVM Express Namespaces
Device NSID Usage Format Controllers
------------ -------- -------------------------- ----------------
----------------
nvme1n1 1 134.22 MB / 134.22 MB 512 B + 0 B nvme0,
nvme1, nvme2
nvme1n2 2 268.44 MB / 268.44 MB 512 B + 0 B nvme2
nvme3n1 3 268.44 MB / 268.44 MB 512 B + 0 B nvme3
Summary:
- Refactored nvme-ns device not to rely on controller during the
setup. [1/11 - 5/11]
- Introduced a nvme-subsys device model. [6/11]
- Create subsystem NQN based on subsystem. [7/11]
- Introduced multi-controller model. [8/11 - 9/11]
- Updated namespace sharing scheme to be based on nvme-subsys
hierarchy. [10/11 - 11/11]
Since RFC V1:
- Updated namespace sharing scheme to be based on nvme-subsys
hierarchy.
Thanks,
[1] https://lists.gnu.org/archive/html/qemu-block/2021-01/msg00425.html
Minwoo Im (11):
hw/block/nvme: remove unused argument in nvme_ns_init_zoned
hw/block/nvme: open code for volatile write cache
hw/block/nvme: remove unused argument in nvme_ns_init_blk
hw/block/nvme: split setup and register for namespace
hw/block/nvme: remove unused argument in nvme_ns_setup
hw/block/nvme: introduce nvme-subsys device
hw/block/nvme: support to map controller to a subsystem
hw/block/nvme: add CMIC enum value for Identify Controller
hw/block/nvme: support for multi-controller in subsystem
hw/block/nvme: add NMIC enum value for Identify Namespace
hw/block/nvme: support for shared namespace in subsystem
hw/block/meson.build | 2 +-
hw/block/nvme-ns.c | 40 ++++++++++------
hw/block/nvme-ns.h | 9 +++-
hw/block/nvme-subsys.c | 101 +++++++++++++++++++++++++++++++++++++++++
hw/block/nvme-subsys.h | 30 ++++++++++++
hw/block/nvme.c | 92 ++++++++++++++++++++++++++++++++-----
hw/block/nvme.h | 5 +-
include/block/nvme.h | 8 ++++
8 files changed, 259 insertions(+), 28 deletions(-)
create mode 100644 hw/block/nvme-subsys.c
create mode 100644 hw/block/nvme-subsys.h
--
2.17.1
